Coronary Heart Disease Tests: What Tests Are Really Necessary?

Investigations for coronary artery disease are not chosen on a "do everything possible" basis, but rather based on the clinical situation. In stable symptoms, the initial evaluation typically begins with a history of symptoms and risk factors, followed by an electrocardiogram, blood tests, and echocardiography, followed by an assessment of the likelihood of obstructive coronary artery disease. Then, either computed tomography coronary angiography (CT coronary angiography) is performed to visualize atherosclerosis and stenosis, or a functional study—stress echocardiography, positron emission tomography (PET), single-photon emission computed tomography (SPECT), or stress magnetic resonance imaging (MRI)—is chosen to determine whether the suspected lesion is causing ischemia. [1]

For acute chest pain, the algorithm is completely different. If a heart attack or other acute coronary syndrome is suspected, the first tests are an electrocardiogram and high-sensitivity cardiac troponin; if necessary, the electrocardiogram and troponin test are repeated. In high-risk patients, urgent invasive coronary angiography may be required, and the examination should not delay the restoration of coronary blood flow. [2]

An important change in current guidelines: routine exercise electrocardiography (ECG) is no longer considered the universal primary test for diagnosing stable coronary artery disease. The 2024 European guidelines recommend anatomical or functional imaging as the first specific test. Computed tomography coronary angiography is particularly useful in cases of low to moderate clinical probability of obstructive disease, while stress imaging is used when it is necessary to prove ischemia and assess its severity. [3]

However, no single test answers all the questions. Electrocardiography reveals the electrical signs of ischemia or previous infarction, echocardiography reveals the function of the heart muscle and valves, computed tomography reveals the anatomy of the coronary arteries, stress tests reveal the functional significance of the lesion, and invasive coronary angiography with fractional flow reserve measurement allows one to directly determine whether a specific stenosis limits blood supply enough to warrant revascularization. [4]

When research needs to be carried out urgently

Urgent diagnosis is required for new chest pain, pressure, squeezing, or burning, especially if the symptom occurs at rest, becomes more severe, or lasts longer than usual. Such symptoms may indicate acute coronary syndrome rather than stable coronary artery disease. [5]

Warning signs include sudden shortness of breath, cold sweat, severe weakness, dizziness, nausea, and pain or discomfort radiating to the shoulder, arm, back, neck, or jaw. Current guidelines consider not only chest pain itself, but also certain types of shortness of breath or unusual weakness, to be equivalent to angina pain. [6]

If acute coronary syndrome is suspected, a 12-lead electrocardiogram (ECG) is recommended to be obtained and interpreted within the first 10 minutes of medical contact. If the initial recording is nondiagnostic but clinical suspicion persists, the ECG is repeated because ischemic changes may appear later. [7]

Cardiac troponin is measured simultaneously, preferably using a high-sensitivity method. If the initial value is inconclusive, repeat measurements are recommended after approximately 1–2 hours, according to the laboratory's specific diagnostic algorithm, when using high-sensitivity troponin. [8]

It is important to note that a normal initial electrocardiogram does not rule out a heart attack, just as a single early normal troponin result does not always rule out acute injury. Therefore, if suspicion persists, dynamic electrocardiograms and serial biomarker measurements are used. [9]

Situation	Initial research	Possible next step
Stable pain with exertion	Electrocardiography, tests, echocardiography	Clinical probability assessment and non-invasive imaging
New pain at rest	Electrocardiography + high-sensitivity troponin	Repeat electrocardiography, serial troponin
Suspected high-risk heart attack	Electrocardiography, troponin	Urgent coronary angiography
Sudden severe shortness of breath	Electrocardiography, troponin, echocardiography	Search for heart attack, heart failure and other causes
Fainting + pain/palpitations	Electrocardiography, monitoring	Exclusion of ischemia and dangerous arrhythmia

Source for the table: [10] [11]

What tests are done first if stable coronary artery disease is suspected?

The initial evaluation typically includes four components: a detailed analysis of symptoms and risk factors, a resting electrocardiogram, basic blood tests, and an echocardiogram. After this, the physician determines the likelihood of coronary artery obstruction and whether a specific coronary blood flow study is needed. [12]

The first stage cannot be replaced by a hardware test. The doctor determines the location of the discomfort, whether it is associated with walking or emotional stress, how quickly it resolves after cessation of stress, whether shortness of breath, weakness, or other angina-like symptoms are present, and also assesses smoking, hypertension, diabetes, lipid disorders, and family history. [13]

A resting electrocardiogram (EKG) is necessary for virtually all patients with suspected coronary syndrome. It can reveal signs of a previous infarction, ischemic changes, and rhythm and conduction disturbances, but a normal ECG does not rule out coronary disease. [14]

Echocardiography reveals left ventricular ejection fraction, regional wall motion abnormalities, hypertrophy, valvular disease, and other causes of dyspnea or pain. This is important not only for diagnosis but also for prognosis and subsequent selection of examination methods. [15]

A basic examination also helps detect diseases that can exacerbate or mimic ischemia. For example, severe anemia increases the workload of the heart, impaired renal function affects cardiovascular risk and the safety of contrast studies, and diabetes mellitus significantly alters the overall risk profile. [16]

After the first stage, the physician assesses the clinical probability of obstructive coronary artery disease. It is this probability, and not simply the presence of the words "chest pain," that determines whether further testing is needed and which method will provide the most useful information. [17]

Primary research	What question does it answer?
Collection of complaints and anamnesis	Do the symptoms resemble coronary ischemia?
Resting electrocardiography	Are there any signs of ischemia, infarction, arrhythmia or conduction disturbances?
Blood tests	Are there any risk factors and conditions that affect ischemia and treatment safety?
Echocardiography	How does the left ventricle work and is there any other structural heart disease?
Clinical Probability Assessment	Is further visualization needed and what kind?

Source for the table: [18]

What blood tests are needed for coronary heart disease?

Routine blood tests alone cannot confirm or rule out chronic coronary artery disease. Their purpose is to identify risk factors, associated conditions, and possible causes of decreased myocardial oxygen supply, as well as to prepare the patient for safe diagnosis and treatment. [19]

A lipid profile is typically assessed: total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglycerides. In patients with established coronary artery disease, these parameters are then used primarily to monitor the effectiveness of lipid-lowering therapy, rather than to confirm the diagnosis itself. [20]

Blood glucose and glycated hemoglobin help identify diabetes mellitus or assess its control. Diabetes is among the factors that increase the clinical likelihood of obstructive coronary disease and long-term cardiovascular risk. [21]

Creatinine and estimated glomerular filtration rate are used to assess kidney function. This information is particularly important before computed tomography (CT) or invasive coronary angiography with iodinated contrast and when choosing certain medications. [22]

A complete blood count (CBC) can detect anemia, among other things. A significant decrease in hemoglobin can impair oxygen delivery to the myocardium and worsen angina even without rapid progression of the coronary stenosis itself. [23]

Cardiac troponin is a fundamentally different test. It is used primarily when acute heart muscle injury is suspected. For routine diagnosis of chronic stable coronary artery disease, a normal troponin does not rule out coronary atherosclerosis or angina. [24]

Analysis	The main role
Lipid profile	Assessment of atherosclerotic risk and treatment effectiveness
Glucose/glycated hemoglobin	Diagnosis and control of diabetes
Creatinine/estimated glomerular filtration rate	Renal and safety assessment of contrast studies
Complete blood count	Detection of anemia and other disorders
Electrolytes	Safety of therapy and assessment of arrhythmic risk
High-sensitivity troponin	Diagnosis of acute myocardial injury

Source for the table: [25] [26]

How is the probability of coronary heart disease calculated before special studies?

Before CT scanning or stress testing, it is recommended to assess the likelihood that symptoms are truly related to obstructive disease of large coronary arteries. The 2024 European guidelines use a risk factor-weighted clinical likelihood model. [27]

The calculation takes into account age, gender, symptom characteristics, and traditional cardiovascular risk factors. Compared with the old model, which relied more heavily on age, gender, and pain characteristics, the new system better identifies people with a very low probability of obstructive disease. [28]

At a clinical probability of 5% or less, European guidelines allow for refraining from further testing for obstructive coronary disease unless there are other concerning clinical findings. This allows for a reduction in the number of tests with low diagnostic yield. [29]

At probabilities greater than 5% to 50%, computed tomography coronary angiography is particularly useful because it is well suited to exclude significant anatomical lesion and simultaneously shows non-obstructive atherosclerosis.[30]

At probabilities greater than approximately 15% to 85%, the role of functional imaging—stress echocardiography, positron emission tomography, or stress magnetic resonance imaging—increases. These ranges partially overlap because anatomical and functional tests answer different clinical questions. [31]

In cases of very high clinical probability - approximately greater than 85%, as well as severe symptoms despite treatment or other high-risk features, invasive coronary angiography may be warranted. [32]

Clinical probability	Typical ESC 2024 approach
≤5%	Consider waiving further testing
>5-50%	Computed tomography coronary angiography is particularly useful.
>15-85%	Functional stress imaging
>85%	Invasive coronary angiography is being considered
Any probability + severe symptoms/high risk	The diagnostic route can be accelerated

Source for the table: [33]

Electrocardiography: What it shows and what it doesn't show

An electrocardiogram is almost always necessary, but a normal electrocardiogram does not rule out coronary artery disease. The recording reflects the heart's electrical activity at a specific moment in time, whereas stable ischemia may only occur during exercise and be completely absent at rest. [34]

An electrocardiogram can detect signs of current or previously experienced ischemia, pathological waves after a heart attack, rhythm and conduction disturbances, ventricular hypertrophy and other changes that influence the further choice of diagnostic method. [35]

In acute coronary syndrome, the role of this method is much greater. Changes in the ST segment and T wave can immediately determine the direction of treatment and the need for urgent reperfusion, but the absence of changes in the initial recording still does not rule out non-ST-segment elevation infarction. [36]

If pain persists or recurs and the initial ECG is unremarkable, repeat recordings are performed. Current US guidelines (2025) explicitly recommend serial ECGs if clinical suspicion persists. [37]

The electrocardiogram also affects the feasibility of performing a routine exercise test. In the presence of baseline repolarization abnormalities, left bundle branch block, artificial stimulation, and certain other changes, interpreting ST segment changes during exercise becomes difficult or impossible, so imaging techniques are preferred. [38]

Electrocardiography result	What does it mean?
Normal ECG at rest	Does not exclude coronary heart disease
Ischemic ST-T changes	Increases suspicion of ischemia
Pathological Q-waves	May indicate a previous heart attack
Rhythm disturbance	Additional monitoring may be required.
Blockade or stimulation	May limit the value of exercise ECG
Dynamic changes in pain	Particularly significant for acute coronary syndrome

Source for the table: [39]

Echocardiography for suspected coronary heart disease

Echocardiography does not show the coronary arteries in the same detail as CT or invasive coronary angiography, but it is one of the primary initial tests. It answers the crucial question: has the suspected ischemia led to dysfunction of the heart muscle and is there another cause for the symptoms. [40]

The physician evaluates the left ventricular ejection fraction, the size of the heart chambers, and the movement of individual wall segments. A regional area that contracts significantly less effectively than adjacent areas may correspond to an area of previous infarction or ischemic damage. [41]

Echocardiography can also detect valvular disease, cardiomyopathy, hypertrophy, and other structural causes of pain or shortness of breath. This is especially important because the same symptom may be associated with more than just the coronary arteries. [42]

A normal echocardiogram does not exclude stable angina: a person may have a normal ejection fraction and normal wall motion at rest, but develop ischemia only when myocardial oxygen demand increases. In this case, stress echocardiography may be necessary. [43]

In cases of known coronary heart disease, repeat echocardiography is especially warranted if new shortness of breath develops, exercise tolerance decreases, or heart failure is suspected. Routine repeated examinations in a completely unchanged condition are usually of less value. [44]

What does echocardiography evaluate?	Practical significance
Ejection fraction	How well does the heart contract?
Regional wall motion	Possible consequences of ischemia or infarction
Dimensions of chambers	Remodeling and heart failure
Valves	Alternative cause of symptoms
Pericardium	Exclusion of other cardiac pathology
Pressure and hemodynamics	Further assessment of dyspnea and cardiac function

Source for the table: [45]

Computed tomography coronary angiography: When it is one of the best tests

Computed tomography coronary angiography is now one of the primary initial specific investigations for suspected stable obstructive coronary disease. Its main strength is its ability to noninvasively visualize the lumen and walls of the coronary arteries, rule out significant stenosis, and simultaneously detect even non-obstructive atherosclerosis. [46]

The 2024 European guidelines particularly recommend this method for patients with low or moderate clinical probability - greater than 5% and up to 50%. In this group, it is most useful to reliably exclude a major obstructive lesion and determine whether coronary atherosclerosis exists at all. [47]

Computed tomography primarily answers the anatomical question: whether there are plaques and how narrowed the lumen is. It is not always able to determine whether the stenosis actually limits blood flow enough to cause ischemia. Therefore, with intermediate stenoses of approximately 40-90%, a functional assessment may be required. [48]

The advantage of this method over a simple calcium index is that computed tomography angiography can detect not only calcified but also non-calcified plaques and directly assess vessel lumen. The calcium index answers a more specific question: how much calcified atherosclerosis is detected. [49]

The quality of computed tomography coronary angiography may be reduced by significant calcification, irregular or excessively rapid rhythm, certain body habitus characteristics, and after complex previous coronary interventions. Furthermore, iodinated contrast is used, so renal function and previous severe reactions to contrast agents are taken into account. [50]

If CT scanning reveals high-risk anatomy or severe stenosis, the patient may be referred for invasive coronary angiography. For intermediate lesions, the current approach seeks to first demonstrate their functional significance to avoid treating a stenosis simply because it appears prominent on imaging. [51]

Possibility of CT coronary angiography	Not really
See coronary plaques	Yes
See non-obstructive atherosclerosis	Yes
Estimate the percentage of anatomical stenosis	Yes
Always prove whether stenosis causes ischemia	No
Replace functional tests completely	No
Used as a primary first test when probability is low to moderate	Yes

Source for the table: [52]

Coronary artery calcium index: It is not the same as coronary angiography

The calcium index measures the amount of calcified atherosclerosis but is not a complete replacement for computed tomography coronary angiography. The study is performed without contrast and is usually expressed in Agatston units. [53]

In the modern European diagnostic strategy, the calcium index can be used as an additional tool to clarify very low or low clinical probability. For example, a zero index in a patient with an initially low probability can further reduce the suspicion of obstructive disease. [54]

However, a zero index does not guarantee the absence of any atherosclerosis in the coronary arteries. Especially in younger patients, plaques may be predominantly non-calcified. [55]

Furthermore, a high calcium index indicates significant atherosclerotic burden but does not allow one to pinpoint the specific stenosis restricting blood flow. Therefore, in a symptomatic patient, the diagnostic strategy is determined by the overall clinical picture. [56]

The American chest pain guidelines also consider calcium scanning as a possible first test in some low-risk patients with stable symptoms. The European 2024 strategy integrates the calcium score more as a modifier of clinical probability rather than as a universal stand-alone test for every patient. [57] [58]

Study	Calcium index	CT coronary angiography
Requires contrast	No	Yes
Shows calcified plaques	Yes	Yes
Shows non-calcified plaques	Limited / no	Yes
Assesses the lumen of the coronary artery	No	Yes
Helps assess overall atherosclerotic risk	Yes	Yes
Used for direct assessment of stenosis	No	Yes

Source for the table: [59]

Stress echocardiography: When ultrasound is beneficial

Stress echocardiography is used to answer the functional question: does myocardial ischemia occur during increased stress? Unlike conventional echocardiography, the heart is assessed during physical or pharmacologically induced stress. [60]

If a certain area of the myocardium receives insufficient blood, it may begin to contract less effectively under stress. The doctor compares the wall motion before and during stress and, based on the nature of the disturbances, assesses the likelihood of functionally significant coronary disease. [61]

One of the advantages of stress echocardiography is the absence of ionizing radiation. Furthermore, it allows for simultaneous assessment of valves, cardiac contractility, blood pressure, and some hemodynamic responses. [62]

A limitation is the dependence of the results on the quality of the ultrasound image and the experience of the specialist. In some patients, it is difficult to obtain a clear visualization of all cardiac segments. [63]

If the patient is able to perform physical activity, the exercise test additionally demonstrates exercise tolerance and the relationship of symptoms to actual physical activity. If walking on a treadmill or pedaling is impossible, pharmacological stress is used according to an appropriate protocol. [64]

The advantage of stress echocardiography	Limitation
Does not use ionizing radiation	Depends on the quality of the ultrasonic window
Shows inducible ischemia	Requires qualified interpretation
Simultaneously evaluates cardiac function	Not all patients have clear enough images.
Physical or pharmacological stress may be possible	There are contraindications to certain types of exercise.

Source for the table: [65]

Myocardial PET and SPECT: Why Perfusion Is Studied

Positron emission tomography and single-photon emission computed tomography (SPECT) assess blood flow distribution within the heart muscle. Comparison of images at rest and under stress helps identify areas of the myocardium that are receiving insufficient blood volume and have increased oxygen demand. [66]

Single-photon emission computed tomography (SPECT) has been used for many years and remains a common method for assessing perfusion. It can determine the presence, location, and approximate extent of ischemia, but it uses a radiopharmaceutical and is associated with radiation exposure. [67]

Positron emission tomography (PET) allows for quantitative measurement of absolute myocardial blood flow and flow reserve. The 2024 European guidelines explicitly recommend PET for absolute blood flow measurement, if the technology is available. [68]

Flow reserve measurement is particularly useful when diffuse disease or microvascular dysfunction is suspected, where a distinct major stenosis may not be present but the ability of the coronary system to increase blood supply during exercise is impaired.[69]

The main limitations of positron emission tomography are its limited availability and high technological complexity. Therefore, the choice between positron emission tomography, single-photon emission computed tomography, stress echocardiography, and magnetic resonance imaging depends not only on theoretical diagnostic effectiveness but also on the capabilities of a particular center. [70]

Method	What shows especially well	Restrictions
SPECT	Regional perfusion and ischemia	Radiation, possible artifacts
PAT	Perfusion + quantitative blood flow and its reserve	Limited availability
PET for suspected microvascular disease	Myocardial blood flow reserve	Requires a specialized center

Source for the table: [71] [72]

Cardiac magnetic resonance imaging with stress

Stress magnetic resonance imaging allows for the simultaneous assessment of ischemia, myocardial structure, contractile function, and scarring without ionizing radiation. Therefore, it is particularly valuable when physicians need to obtain not only information about coronary blood flow but also a detailed characterization of the heart muscle itself. [73]

Perfusion imaging evaluates the flow of contrast agent into the myocardium during pharmacological loading. An area with relatively insufficient blood supply is identified as a perfusion defect. [74]

Magnetic resonance imaging is particularly useful when it is necessary to differentiate ischemic injury from myocarditis or cardiomyopathy, to evaluate the infarction scar, or to determine myocardial viability.[75]

The method is not suitable for some patients with certain incompatible implants or other contraindications to magnetic resonance imaging. Gadolinium-based contrast is also used, so its use in cases of severe renal dysfunction is assessed separately. [76]

Another limitation remains availability: high-quality cardiac stress MRI requires specialized equipment and a team with expertise in cardiac MRI. [77]

Possibility of stress MRI	Practical significance
Assessment of ischemia	Yes
Post-infarction scar assessment	Yes
Assessment of ventricular function	Yes
Ionizing radiation	No
Detailed characteristics of the myocardium	One of the main advantages
Availability	Lower than conventional echocardiography

Source for the table: [78]

Exercise ECG: Is a treadmill test or bicycle ergometry necessary today?

Conventional stress electrocardiography may still be useful, but its diagnostic role has become significantly less important than it once was. Current European guidelines prefer computed tomography coronary angiography or stress imaging, if available and technically feasible.[79]

During the test, the patient walks on a treadmill or works on a bicycle ergometer, and the physician monitors the electrocardiogram, blood pressure, pulse rate, symptoms, and physical performance. The appearance of characteristic pain, ST segment changes, or poor exercise tolerance may increase the suspicion of coronary heart disease. [80]

The problem is that stress electrocardiography has lower diagnostic accuracy than modern imaging studies, and the results can be both false positive and false negative. Therefore, the treadmill test result alone is not always sufficient for a definitive diagnosis of obstructive coronary disease. [81]

The American chest pain guidelines are somewhat less categorical: in some low-risk patients with stable pain and an interpretable baseline electrocardiogram, exercise electrocardiography may remain a reasonable first test. This is an example of a real difference between guidelines that should be considered when interpreting prescriptions. [82]

The method retains its own practical value: it allows for an objective assessment of physical performance, heart rate, blood pressure response, and the relationship of symptoms to exercise. Therefore, its abandonment as a universal first test does not mean it has become useless. [83]

Question	Answer
Is stress ECG still an available method?	Yes
Is this the best first test for most patients?	No
Can demonstrate physical performance?	Yes
Can it give a false positive result?	Yes
It may be uninformative given the initial ECG changes?	Yes
Can it be used in certain situations?	Yes

Source for the table: [84] [85]

Holter Monitoring: Does it Diagnose CHD?

Holter monitoring is not the primary diagnostic method for obstructive coronary atherosclerosis. Its primary purpose is to record cardiac rhythm over time and associate episodes of palpitations, fainting, irregular heartbeats, or other symptoms with electrical events. [86]

In patients with coronary artery disease, Holter is particularly useful when underlying arrhythmia is suspected. It can detect episodes of atrial fibrillation, pauses, tachycardia, extrasystoles, and some other rhythm disturbances that may not be present during a brief electrocardiogram in the doctor's office. [87]

Monitoring sometimes detects ST segment changes, but diagnosing or ruling out coronary stenosis using Holter alone is usually incorrect. More reliable anatomical and functional methods exist for this purpose. [88]

If the main complaint is rare attacks of palpitations or fainting, the duration of monitoring is selected according to the frequency of symptoms: a standard day may not be enough, and then longer external or implantable recorders are used. [89]

Therefore, the statement "A normal Holter means no coronary heart disease" is incorrect. Normal 24-hour monitoring primarily means that no significant electrical pathology capable of detection by this method was detected during the recording period. [90]

What do they look for with Holter?	Is the method suitable?
Atrial fibrillation	Yes
Paroxysmal tachycardia	Yes
Bradyarrhythmia and pauses	Yes
Relationship of symptoms with rhythm	Yes
Anatomical stenosis of the coronary artery	No
Completely exclude coronary heart disease	No

Source for the table: [91]

Invasive coronary angiography: when is it really needed?

Invasive coronary angiography remains the most detailed method for assessing coronary artery lumen, but it is not currently used as the first test for every patient with stable chest pain. Current strategies attempt to initially select patients with a high probability of disease or a high probability that the result will lead to revascularization. [92]

European guidelines recommend invasive coronary angiography in the presence of a very high pre- or post-test probability of obstructive disease, severe symptoms despite optimal medical therapy, angina at low exertion, or evidence of a high risk of future events.[93]

During the examination, a thin catheter is inserted into the coronary artery orifices, contrast is injected, and the vessels are visualized radiographically. If intermediate stenosis is detected, visual impressions alone are often insufficient for a decision on stenting. [94]

Therefore, current guidelines recommend assessing the functional significance of intermediate stenoses using intravascular pressure measurements—fractional flow reserve or instantaneous wave-free ratio. These parameters help determine whether a particular lesion is truly limiting coronary blood flow. [95]

This approach is fundamentally important: coronary angiography reveals anatomy, while fractional flow reserve reveals physiology. A stenosis may appear quite pronounced but not be functionally significant, or, conversely, a visual assessment may underestimate its impact. [96]

Because coronary angiography is an invasive procedure, the risks of vascular complications, bleeding, contrast, and other rare complications are considered. Its benefits must outweigh the potential risks. [97]

Method	What does it show?
Invasive coronary angiography	Anatomy and severity of stenosis
Fractional flow reserve	Does stenosis affect blood flow during maximum hyperemia?
Instant waveless attitude	Functional significance without pharmacological hyperemia
Intravascular ultrasound	Vessel and plaque from the inside
Optical coherence tomography	Detailed structure of the wall and stent

Source for the table: [98]

Intravascular ultrasound and optical coherence tomography

Intravascular ultrasound and optical coherence tomography are not routine initial tests for a person presenting with chest pain for the first time. They are used within the coronary arteries during invasive imaging when it is necessary to thoroughly evaluate the lesion structure or optimize stent placement. [99]

Intravascular ultrasound (IVUS) visualizes the lumen, vessel size, and plaque structure using an ultrasound transducer placed directly within the coronary artery. This is particularly useful for complex lesions. [100]

Optical coherence tomography provides images with very high spatial resolution and helps to assess plaque structure and the quality of stent placement. [101]

The 2024 European guidelines recommend intravascular imaging in complex stenting, particularly in left main coronary artery lesions, true bifurcations and long lesions.[102]

The 2025 US acute coronary syndrome guidelines also enhanced the role of intravascular imaging, with its use to guide stenting receiving a strong recommendation in complex lesions.[103]

Method	When it is especially useful
Intravascular ultrasound	Complex and large lesions, stent optimization
Optical coherence tomography	Detailed assessment of the lesion structure and stent
Fractional flow reserve	Deciding whether stenosis is functionally significant
Conventional angiography	Primary anatomical map of vessels

Source for the table: [104]

What to do if the coronary arteries are “clean” but angina remains

The absence of significant stenosis in major coronary arteries no longer automatically means that pain is not related to the heart. The current concept includes angina or ischemia in non-obstructive coronary arteries—conditions associated, for example, with microvascular dysfunction or coronary spasm. [105]

This is one of the most important changes to the 2024 guidelines. Previously, a patient with a normal coronary angiogram might be given the conclusion that "the heart is fine" even though symptoms persisted. Now, with a compelling clinical picture, the diagnostic search can continue. [106]

Positron emission tomography and magnetic resonance imaging are capable of assessing myocardial blood flow reserve and providing non-invasive information on microvascular function. [107]

The most comprehensive invasive assessment of coronary function includes measurements of blood flow reserve, microvascular resistance, and provocative tests to detect coronary spasm. Intravascular administration of acetylcholine using a specialized protocol can be used to provoke spasm. [108]

The 2024 European guidelines have strengthened the role of such testing: if symptoms persist and the diagnosis is unclear after non-invasive testing, invasive functional testing allows the specific mechanism – the endotype – to be identified and then treatment to be selected more targeted. [109]

Therefore, normal or nearly normal angiography does not equal normal function of the entire coronary system. The great vessels are only one level of the coronary circulation; there is also microcirculation and vasomotor regulation. [110]

Situation	What is being researched next?
Angina pectoris + no significant stenosis	Possible ANOCA/INOCA
Suspected microvascular dysfunction	Myocardial blood flow reserve
Suspected spasm	Provocative coronary testing
Symptoms persist despite treatment	Invasive functional testing in a specialized center
CT/angiography "normal"	Do not exclude functional coronary disease

Source for the table: [111]

How a specific study is selected

There is no single "most accurate" test that is suitable for all patients. The best test is considered to be the one that answers a specific clinical question with the lowest risk and is most likely to change future management. [112]

If the primary goal is to exclude obstructive lesions and detect atherosclerosis, especially in low to moderate clinical probability, computed tomography coronary angiography is a logical first choice.[113]

If the goal is to prove that the symptoms are related to ischemia, to determine its severity, or to resolve the issue of the functional significance of an already identified lesion, stress imaging is chosen. [114]

If the patient cannot perform physical activity due to arthrosis, neurological disease or severe limitation of mobility, this does not exclude a functional examination: stress can be induced by a drug during echocardiography, magnetic resonance imaging or nuclear imaging. [115]

In cases of severe coronary calcification, CT may be less able to evaluate the lumen of the vessel; in this situation, functional testing sometimes provides more useful information. [116]

In cases of significant renal dysfunction, contrast-enhanced techniques are evaluated with particular care. This does not automatically prohibit coronary angiography, but the choice of technique and preventive measures should take into account renal function and potential clinical benefit. [117]

Following previous stenting or bypass surgery, the algorithm also differs from that for a patient without known coronary disease. If symptoms recur, stress imaging, CT scan of the bypass grafts, or invasive coronary angiography may be used, depending on the suspected cause and known anatomy. [118]

Clinical question	A study that often fits better
Is there anatomical coronary stenosis?	CT coronary angiography
Is there ischemia under load?	Stress visualization
How does the left ventricle work?	Echocardiography
Is there an acute infarction?	Electrocardiography + high-sensitivity troponin
Is intermediate stenosis functionally significant?	FFR/iFR or functional imaging
Is there microvascular dysfunction?	PET/MRI with reserve assessment or invasive functional testing
Is there arrhythmia?	Holter or longer-term monitoring
How is complex stenosis structured from the inside?	IVUS / OCT

Source for the table: [119] [120]

What tests are needed for established coronary heart disease?

In cases of confirmed coronary artery disease, there is no need to repeat complex tests annually simply because a certain period has passed. American guidelines for chronic coronary artery disease explicitly state that routine periodic anatomical or ischemic testing without changes in clinical or functional status is not recommended. [121]

The main monitoring tool remains clinical assessment: whether angina, shortness of breath, physical endurance have changed, whether palpitations, fainting or signs of heart failure have appeared. [122]

If symptoms become more frequent or severe, new shortness of breath develops, or cardiac function worsens, testing is repeated in a targeted manner. This may include echocardiography, functional imaging, computed tomography, or coronary angiography, depending on the clinical need. [123]

After stenting, routine coronary CT scanning should not be used simply as a routine checkup in every asymptomatic patient. Similarly, after bypass surgery, coronary angiography should not be automatically performed without clinical indications. [124]

Routine monitoring also includes laboratory monitoring of risk factors and treatment - primarily lipids, glycemic status and renal function in appropriate clinical situations. [125]

The practical principle of modern diagnostics can be formulated as follows: stable condition – clinical observation and prevention; changed condition – a new diagnostic question and a targeted test. [126]

Situation with known coronary heart disease	Is a new test needed?
There are no complaints, the condition has not changed.	Usually complex tests are not necessary
Angina has become more frequent	Yes, a re-evaluation is required.
New shortness of breath has appeared	Echocardiography and search for the cause are often needed.
Suspected arrhythmia	Rhythm monitoring
Symptoms after stent	Stress test/CT/angiography as needed
New pain at rest	Emergency algorithm for acute coronary syndrome

Source for the table: [127]

What does a normal test result mean?

A normal result from one test typically excludes only the pathology that the test can reliably detect. For example, a normal resting electrocardiogram does not exclude stress ischemia, and a normal Holter does not prove the absence of coronary atherosclerosis. [128]

A normal CT coronary angiography without plaques or stenosis greatly reduces the likelihood of obstructive atherosclerotic coronary disease. However, vasospastic or microvascular angina may still be present if convincing symptoms persist. [129]

A normal stress test reduces the likelihood of significant inducible ischemia but does not mean the absence of any atherosclerotic plaque. Functional testing and anatomical imaging assess different aspects of the disease. [130]

Even coronary angiography does not always complete the diagnosis. If large coronary arteries do not have obstructive lesions, but angina persists, a modern algorithm suggests considering disturbances in microcirculation and coronary vasomotor response. [131]

This is why test results should be interpreted in conjunction with symptoms and baseline clinical risk. The same "questionable" test has a different meaning in a patient with very low and very high baseline risk. [132]

Normal test	What it does NOT necessarily exclude
Resting ECG	Stable stress ischemia
Echocardiography	Obstructive coronary artery disease with preserved cardiac function
Halter	Coronary atherosclerosis
Calcium index 0	Any non-calcified plaque
Stress test	Non-obstructive atherosclerosis
Coronary angiography without stenosis	Microvascular or vasospastic angina

Source for the table: [133] Source for the table: [134]

How does examination for stable coronary artery disease differ from diagnosing a heart attack?

Stable coronary artery disease and acute myocardial infarction require fundamentally different diagnostic algorithms. In a stable situation, clinical probability can be assessed sequentially and the optimal noninvasive examination selected; when myocardial infarction is suspected, speed and the exclusion of an immediate threat to life become the priority. [135]

In acute pain, an electrocardiogram should be performed as soon as possible, and high-sensitivity troponin should be measured serially. If the electrocardiogram shows ST-segment elevation infarction, restoration of coronary blood flow should not be delayed while awaiting troponin results. [136]

Since August 28, 2026, the Fifth Universal Definition of Myocardial Infarction, jointly developed by the European Society of Cardiology, the American College of Cardiology, the American Heart Association, and the World Heart Federation, has been in effect. It clarifies the diagnostic classification of infarction and emphasizes the role of cardiac troponin and imaging in establishing the mechanism of injury. [137]

The new definition also highlights the need to use sex-specific 99th percentile values for cardiac troponin when they are validated for a particular assay to reduce systematic underrecognition of myocardial injury in women.[138]

Elevated troponin alone signifies myocardial injury, but not always infarction due to atherothrombosis. Diagnosis requires clinical context and evidence of an ischemic mechanism; troponin may also be elevated in other severe cardiac and non-cardiac conditions. [139]

Stable suspicion of coronary heart disease	Suspected acute myocardial infarction
Clinical probability	Immediate risk assessment
Resting ECG	Urgent ECG
Echocardiography	Troponin
CT coronary angiography or stress imaging	Serial ECG and troponin
Planned coronary angiography according to indications	Urgent coronary angiography in appropriate patients

Source for the table: [140]

What has changed in the diagnosis of coronary heart disease in recent years?

The main change is the shift from "doing stress ECG for almost everyone" to individualized choice of anatomical or functional imaging. The 2024 European guidelines have made computed tomography coronary angiography and modern stress imaging techniques central to the initial diagnosis. [141]

The second change is a new clinical probability model that takes risk factors into account and allows unnecessary testing to be avoided in more patients with a very low probability of obstructive disease.[142]

In 2026, the model continues to be debated: experts acknowledge its utility and ability to improve patient selection, but point to limitations, including the origin of the original cohort and the model's inability to assess the likelihood of microvascular dysfunction. [143]

The third change is the recognition of ANOCA and INOCA as a full-fledged part of the spectrum of coronary syndromes. Normal large vessels are no longer considered automatic proof that anginal symptoms are of non-cardiac origin. [144]

The fourth change is the increased use of functional measurement of stenoses during invasive coronary angiography. Visual assessment of stenosis is increasingly considered a sufficient basis for stenting intermediate lesions. [145]

The fifth change concerns the surveillance of established disease: the current strategy abandons annual stress testing and anatomical studies in a completely stable asymptomatic patient unless the result is going to be used to change treatment. [146]

Earlier	Now
The stress ECG was the main test	CT or stress imaging are most often preferred.
Pre-test probability is mainly age + gender + symptoms	Risk factors added
Normal angiography often completed the examination	ANOCA/INOCA are being considered
Intermediate stenosis was often assessed visually.	Physiological assessment of FFR/iFR is used
Stable patients were frequently given repeated tests according to the calendar.	Testing is associated with a change in state

Source for the table: [147] Source for the table: [148]

What is often misunderstood

Myth: A normal electrocardiogram means there is no coronary artery disease. An electrocardiogram reflects the condition at the time of recording, so stable ischemia that occurs only during exercise may not leave any signs. [149]

Myth: Holter monitoring can fully assess the heart for coronary artery disease. Holter monitoring primarily assesses rhythm. It is useful for arrhythmias and episodic symptoms, but does not replace coronary imaging or modern functional testing. [150]

Myth: The more tests performed, the more reliable the diagnosis. Sequentially "layering" tests increases cost, the number of incidental findings, and the likelihood of false positives. Current guidelines recommend choosing the test that is most likely to immediately answer the clinical question. [151]

Myth: If coronary angiography reveals a 60-70% stenosis, it must be stented. For intermediate stenoses, it is important to determine the functional significance using stress imaging or invasive physiological measurements. [152]

Myth: If coronary angiography is normal, the symptoms are definitely not cardiac. Microvascular dysfunction and coronary spasm can cause true angina and ischemia in the absence of large artery obstruction. [153]

Myth: A patient with a stent should undergo coronary angiography every year. In a stable condition without new symptoms, routine periodic anatomical or ischemic studies are not recommended for monitoring purposes only. [154]

Myth	What is true?
A normal ECG rules out coronary artery disease.	No
Holter replaces coronary angiography	No
Any stenosis needs to be stented.	No
Normal large vessels exclude a coronary cause of pain	No
You need to do a stress test every year.	Usually not present in stable condition.
The best test is the same for everyone	No

Source for the table: [155]

Practical examination algorithm for suspected coronary heart disease

Step 1: Determine whether the situation is stable or acute. New pain at rest, rapid worsening, severe dyspnea, or other signs of acute coronary syndrome require an immediate algorithm with electrocardiography and troponin. [156]

Step 2: If symptoms are stable, perform an initial clinical assessment, electrocardiogram, baseline tests, and echocardiogram. Risk factors and possible alternative causes of symptoms are also identified. [157]

Step 3 is to assess the clinical probability of obstructive coronary disease. If the probability is very low, further testing may be unnecessary; if the probability is higher, anatomical or functional testing is chosen. [158]

Step 4: If it is important to exclude anatomical disease, use computed tomography coronary angiography. This approach is particularly suitable for patients with a low or moderate probability of obstructive disease. [159]

Step 5: If ischemia needs to be proven or the functional significance of the disease needs to be assessed, choose stress imaging. This may include stress echocardiography, positron emission tomography, single-photon emission computed tomography, or stress magnetic resonance imaging. [160]

Step 6: In cases of very high probability, high-risk anatomy, or severe symptoms, consider invasive coronary angiography. Intermediate stenoses should preferably be physiologically assessed before deciding on revascularization. [161]

Step 7: If there are no significant stenoses but symptoms persist, do not automatically stop the search. Microvascular dysfunction and vasospasm should be considered and, if necessary, a specialized functional study of the coronary system should be performed. [162]

Simplified decision tree

Clinical situation	The next step
New/unstable pain	ECG + high-sensitivity troponin
Stable symptoms	ECG + tests + echocardiography
The probability of obstructive coronary artery disease is ≤5%	Often, it is not necessary to perform a specific test
Low-moderate probability	CT coronary angiography
Moderate-high probability	Stress visualization
Very high probability / severe symptoms	Invasive coronary angiography
Intermediate stenosis	Functional assessment
There is no stenosis, but angina persists	ANOCA/INOCA diagnostics

Source for the table: [163]

Frequently Asked Questions

What test best detects coronary artery disease?

There is no universally best test. Computed tomography coronary angiography is particularly useful for detecting anatomical coronary atherosclerosis, and functional stress imaging is useful for demonstrating ischemia. [164]

Is it possible to detect coronary heart disease using a regular ECG?

Sometimes an electrocardiogram provides important clues, but a normal ECG does not rule out coronary artery disease. In stable disease, ischemic changes may only occur during exercise. [165]

Is it necessary to do Holter monitoring if coronary heart disease is suspected?

Not for everyone. Holter is particularly useful for palpitations, fainting, or suspected arrhythmia, but is not a primary test for coronary stenosis.[166]

Which is better - a treadmill test or CT coronary angiography?

For the initial diagnosis of obstructive disease, the current European strategy often favors computed tomography or stress imaging. The treadmill test remains useful in certain situations and for assessing physical performance. [167]

Which is better - CT coronary angiography or stress echocardiography?

They answer different questions. CT scans reveal the anatomy of blood vessels, and stress echocardiography reveals whether stress causes ischemic myocardial dysfunction. [168]

Is it possible to detect coronary heart disease on a heart ultrasound?

Echocardiography can show the consequences of ischemia, but not always coronary stenosis itself. A normal echocardiogram therefore does not exclude stable coronary disease. [169]

Is troponin needed for stable angina?

Troponin is typically used primarily when acute myocardial injury is suspected. A normal troponin does not exclude chronic stable coronary artery disease. [170]

When is coronary angiography needed?

It is particularly indicated when there is a very high probability of obstructive disease, severe symptoms despite treatment, high risk, or the need to make a decision on revascularization.[171]

Is it necessary to stent 50-70% stenosis?

Not automatically. Intermediate stenoses should preferably be assessed functionally to determine whether they are truly flow-limiting.[172]

What is FFR?

Fractional flow reserve is an invasive measurement that assesses how much a specific coronary stenosis limits blood flow. It helps decide whether revascularization of the lesion is warranted. [173]

Is it possible to have angina with a normal coronary angiography?

Yes. Microvascular angina and coronary vasospasm are possible - ANOCA/INOCA variants. [174]

Is it necessary to have a stress test annually if you have established coronary artery disease?

No, unless the clinical and functional status has changed. Routine periodic testing without a new clinical question is not recommended. [175]

Which is more informative - PET or SPECT?

Positron emission tomography has the important advantage of being able to quantify myocardial blood flow and its reserve. When technology is available, European guidelines prefer PET for absolute blood flow measurement. [176]

When is cardiac magnetic resonance imaging useful?

It is particularly useful when it is necessary to simultaneously assess ischemia, cardiac function and the condition of the heart muscle itself - for example, a scar after a heart attack or possible cardiomyopathy.[177]

If all the tests are normal, but the pain remains, what should I do?

The diagnosis should be reconsidered rather than automatically discontinuing the investigation. In addition to non-cardiac causes, microvascular coronary dysfunction and vasospasm should be considered if the symptoms truly resemble angina. [178]

Key points from experts

Christiaan JM Vrints is Professor Emeritus at the University of Antwerp, a cardiologist, and co-chair of the European Society of Cardiology's 2024 Guidelines Task Force on Chronic Coronary Syndromes. The guidelines, co-chaired by him, emphasize that diagnosis should be stepwise: first, clinical assessment, electrocardiography, and echocardiography, then calculation of the probability of obstructive disease, and only then the choice of anatomical or functional testing. [179] [180]

Felicita Andreotti is a professor of cardiology at the Fondazione Policlinico Universitario Agostino Gemelli and co-chair of the 2024 European Society of Cardiology guidelines. In the working group's published algorithm, the correct choice of the first specific test is of key importance: computed tomography coronary angiography is used primarily to exclude obstructive disease and detect atherosclerosis, and functional imaging is used to prove ischemia and make decisions about revascularization. [181] [182]

Juhani Knuuti, MD, professor and director of the Turku PET Centre at the University of Turku, is a specialist in cardiovascular imaging. His research interests include positron emission tomography, single-photon emission computed tomography, echocardiography, magnetic resonance imaging, and computed tomography in coronary artery disease. The practical implication of modern multimodality imaging is that different methods do not compete for the status of the "single best" but are used to answer different anatomical and functional questions. [183]

Stephan Achenbach is a professor and head of the Cardiac Computed Tomography Working Group at the University Hospital Erlangen. His research focuses on the diagnostic accuracy of coronary computed tomography, the assessment of coronary atherosclerosis, and the use of tomography for intervention planning. The current position of computed tomography in guidelines reflects this evolution: it has become a fully-fledged first-line diagnostic tool for many patients, not just an alternative to invasive angiography. [184] [185]

Key points about coronary heart disease research

Today, the diagnosis of coronary artery disease is based not on a single test, but on the correct sequence of investigations. First, it is necessary to determine whether the situation is stable, assess symptoms and risk factors, perform an electrocardiogram, tests, and echocardiography, and then determine the likelihood of obstructive coronary artery disease. [186]

For stable disease, the main modern options are computed tomography coronary angiography and functional stress imaging. The former provides better insight into anatomy and atherosclerosis, while the latter provides insight into the presence and severity of ischemia. [187]

Routine stress electrocardiography (ECG) has not disappeared from practice, but it should no longer automatically be the first diagnostic test for every patient. This is especially important to remember when there are baseline ECG changes or when more precise imaging is available. [188]

Invasive coronary angiography is also not necessary for everyone. It is especially important in cases of high disease probability, severe symptoms, high-risk noninvasive test data, and suspected revascularization; intermediate stenoses are recommended to be functionally assessed. [189]

Finally, normal large coronary vessels do not always complete the diagnostic search. In persistent angina, microvascular dysfunction and vasospasm—one of the most important diagnostic updates in the latest guidelines—must be considered. [190]