IMPACT OF COLLATERAL CIRCULATION ON BLOOD SUPPLY AND FUNCTION OF MYOCARDIUM

Abstract

Aim. To evaluate perfusion and functioning of myocardium in occluded coronary artery with various types of collateral blood flow.Material and methods. Ninety patients with three-vessel disease and obligate occlusion of the right coronary artery (RCA) according to the type of collateral flow development, were selected to 2 groups: first — 44 patients (49%) with I and II grades by Rentrop, second — 46 patients (51%) with grade III Rentrop collaterals. Perfusion scintigraphy data was analysed, with echocardiography and tissue Doppler.Results. Worsening of perfusion of myocardium inferior wall was found in patient of group 2 with non-significant defect of perfusion in 1st group patient. Stable perfusion defect in group 1 was 9,8±3,5%, in group 2 — 4,1±1,7%. While comparing tissue Doppler values, change in longitudinal deformation of inferior wall in the group with worse collaterals was -4,1±2,6, in group 2 -6,8±2,7. While assessing segmentary contractility of the inferior wall of the left ventricle, lower number of hypokinesis segments was found in group 2.Conclusion. Chronic occlusion of coronary artery with a weak collaterals is followed by worse parameters of local perfusion and function of myocardium. In a good condition of collaterals, regardless the non-significant perfusion disorders in myocardium at rest, there are prominent stress-defects and local contractility disorders of myocardium.

Keywords

• coronary heart disease
• collateral blood supply
• chronic occlusion of coronary arteries