Features of heart damage in systemic scleroderma

Presumptive mechanisms of cardiac pathology in systemic scleroderma (SSD) include ischemic damage, myocarditis, progressive fibrosis, systemic hypertension and pulmonary arterial hypertension (PAH) with the development of chronic pulmonary heart.

One of the important hypotheses of heart failure in systemic scleroderma is ischemic injury of intramural vessels with the development of fibrinoid necrosis, fibrosis and intimal hypertrophy with narrowing of the lumen, which is manifested by angina pectoris, acute myocardial infarction and sudden death.

Typical morphological changes are linear necrosis of cardiomyocytes, the appearance of which is associated with transient vasospasm due to local Raynaud's syndrome. Most patients with systemic scleroderma with proven coronary artery disease have signs of peripheral Raynaud's syndrome.

Along with such mechanisms of ischemic damage in SDS, as a spasm of the coronary arteries, lesion of the microcirculatory channel, occlusive damage of the heart vessels, discuss the contribution of the macrovascular unit (coronary arteries) to the development and progression of the heart pathology. Previously, it was believed that coronary arteries in systemic scleroderma intact and cardiosclerosis is not a consequence of angiogenic processes. At the present time, the thickening of the intima of the coronary vessels, the narrowing of their lumen, is shown, which indicates the complex origin of scleroderma cardiosclerosis,

The mechanisms of the development of pulmonary hypertension in systemic scleroderma are not fully understood. Inflammation is considered as the main pathogenetic factor. Induration by macrophages and T-lymphocytes of the vascular wall was noted both in the primary PAH and in association with SSD. Inflammation cells produce growth factors, such as platelet-produced growth factor, vascular endothelial growth factor, which is given great importance in the pathogenesis of pulmonary hypertension. In patients with systemic scleroderma, antinuclear and antihistone antibodies are associated with vascular lesions.

The traditional concept of the development of pulmonary hypertension as a result of pulmonary vasoconstriction in recent years has undergone significant changes. However, some authors indicate that in patients with SSD who have pulmonary hypertension, Raynaud's syndrome is more common than in patients without it, so the authors consider the hypothesis of the existence of the so-called pulmonary Raynaud's syndrome.

In the genesis of pulmonary hypertension in systemic scleroderma, an endothelium-dependent vasodilation disorder was found to be associated with a decrease in endothelial NO synthase activity. In addition to nitric oxide, endothelial cells produce a vasodilating factor of prostacyclin that is involved in providing aititrombogenic properties of the vascular wall and affecting proliferative processes in intima and adventitia of the lung vessels. A decrease in prostacyclin expression was found in patients with severe pulmonary hypertension associated with SSD.

With complicated pulmonary hypertension, chronic inflammation of the vasoconstrictor peptide endothelin-1, as well as serotonin, especially in the expressed Reynaud syndrome, is noted. Pulmonary thrombosis in situ is one of the pathogenetic mechanisms of pulmonary hypertension in systemic scleroderma, most often realized with concomitant antiphospholipid syndrome.

[1], [2], [3], [4], [5], [6], [7]

Symptoms of heart damage in systemic scleroderma

With systemic scleroderma, the lesion of all three membranes of the heart is described: myocardial damage is observed in 83-90%, endocardial - in 18-35%, pericardium - in 13-21% of cases. Often there are multisegmental disturbances of myocardial perfusion at rest or under load, myocardial fibrosis, focal cardiosclerosis with the phenomena of progressive chronic heart failure.

It was found that in systemic scleroderma with lesion of skeletal muscles, myocardial pathology occurs in 21% of cases and in 10% in patients without skeletal myopathy.

Clinically pronounced myocarditis is rare, that is in dissociation with autopsy, which is often marked by focal or diffuse myocardial fibrosis and linear necrosis of cardiomyocytes. Features of myocarditis in SSD - the absence of significant pathology of large coronary arteries and frequent lesion of the right ventricle and subendocardial by the myocardium.

Endocardial damage in systemic scleroderma is less common than myocardium, and is characterized by marginal sclerosis and shortening of mitral valve chords with the development of mitral insufficiency and prolapse of the mitral valve.

Changes in the pericardium (fibrinous, adhesive, exudative pericarditis) are observed in 15-20% of patients, and they are associated with a local cutaneous form of systemic scleroderma. Clinical signs: dyspnea, orthopnea and edema. Tamponade of the heart, as a rule, does not develop due to a small pericardial effusion. It should be noted that pericarditis can develop as a primary manifestation of systemic scleroderma, hack and as a result of uremia. The possibility of pancarditis - combined myocardial, pericardial and endocardial lesions with a characteristic predominance of fibrosis processes is shown.

The development of systemic arterial hypertension in systemic scleroderma is due to both renal vessel damage and iatrogenic (glucocorticoid treatment) causes. High incidence of interstitial lung injury and development of PAH creates prerequisites for the development of the pulmonary heart

The incidence of pulmonary hypertension in patients with systemic scleroderma varies from 0 to 60%. In about 33% of patients with diffuse form of systemic scleroderma, pulmonary hypertension is established - as an isolated one, as well as caused by interstitial lung involvement. In patients with CREST-syndrome, PAH is more common (60%). The development of PAH causes the death of a number of patients with SSD and largely determines the prognosis for life. Two-year survival of patients with CREST-syndrome and PAH is 40%, while in the absence of PAH, 80%.

The main clinical manifestation of pulmonary hypertension in systemic scleroderma is shortness of breath when exercising. Other symptoms are palpitation, as well as signs of a lack of right ventricle, especially edema and ascites. In the last decade, the problem of remodeling the right heart in the PAH has been discussed in domestic and foreign literature. A significant dependence of the expansion of the right ventricular cavity and hypertrophy of its wall on the degree of PAH, the degree of decrease in the ejection fraction and the growth of PAH is established, which raises the question of the need to identify early signs of heart involvement, both right and left, in order to define a "therapeutic window" for influence on the basic mechanisms of progression of systemic scleroderma.

The objective signs of pulmonary hypertension, found in auscultation of the heart, include the accent and / or bifurcation of the first tone over the pulmonary artery or strengthening it by inhalation. However, they appear only when the pressure in the pulmonary artery is increased 2-fold. Pulsation in the second intercostal space to the left, the appearance of systolic and diastolic murmurs are recorded only with severe pulmonary hypertension.

The development of heart damage in systemic scleroderma in most cases occurs gradually, for 4-6 years, but the process progresses steadily, leading to CHF. In 30% of cases, heart disease is the direct cause of death in STD patients.

Pathophysiological aspects of cardiac pathology in systemic scleroderma include: cardiac Raynaud's syndrome with vasospasm and microcirculation disorder, accelerated atherogenesis in the background of immune inflammation, development of autoimmune myocarditis, fibrosis of the heart, which underlies the progression of congestive heart failure.

Subclinical damage to the cardiovascular system is often confirmed by autopsy data.

Clinically significant heart damage with systemic scleroderma, rhythm disturbances and myocardial conductivity, ischemia, systemic pulmonary hypertension and congestive heart failure are associated with poor prognosis.

The presence of chronic pulmonary heart determines the high disability of patients and is associated with progressive pulmonary arterial hypertension, which dictates the need for the development of modern pathogenetically substantiated treatment of systemic sclerosis, complicated by cardiovascular pathology.