Clinical determinants of Coronary Collaterals - An Angiography study.

Coronary artery disease (CAD) is the leading cause of death in developed countries and may become the most important reason for mortality in the developing countries. Early interventions of these patients with CAD by improving anginal symptoms, coronary blood flow with anti-anginal medication, mechanical intervention as percutaneous angioplasty and coronary stenting or coronary artery bypass grafting can minimize the mortality and morbidity. The aim of the intervention is to reduce cardiovascular mortality by reducing the myocardial infarction size and to improve the left ventricular function. However, in extensive CAD, 20–30% of patients may not be suitable for revascularization as angioplasty or surgical bypass and carry a poor prognosis. Hence an alternative treatment strategy for revascularization that improves symptoms as well as the progression of CAD becomes essential. In normal persons without significant CAD, myocardial blood flow is by the major coronary arterial branches. Side branches originate from the main branch and terminate as an extensive capillary network supply different regions of the myocardium. When one of the major pathways is severely obstructed by an atherosclerotic lesion, flow distal to the lesion is compromised. Functional and structural capacity of myocardium depends on the adequacy of flow through the alternate coronary pathways or coronary collaterals. This study is carried out to find the clinical determinants of coronary collateral in patients with total or subtotal occlusion on coronary angiography and to correlate with grading of collaterals. The information obtained may add and cryatallize to the testimony of others to make it a fruitful wisdom. AIMS AND OBJECTIVES: 1. To study the impact of type of coronary artery disease in coronary collateral development. 2. To study the role of conventional coronary risk factors in the coronary collateral development. 3. To study the coronary collateral number, types and its relationship with the coronary artery involved in total and subtotal coronary artery occlusion. CONCLUSION: STEMI was the most common clinical presentation. LAD is the most common artery occluded. Both homo and hetero collateral together were the commonest mode of collateral supply. Collateral to LAD most commonly arise from RCA. Collateral to RCA and LCX most commonly arise from LAD. The predominance of Grade II collaterals were observed in patients with CSA, recurrent CAD, smokers, systemic hypertension and patient with no conventional risk factors. Poorly formed collaterals (Grade 0 & Grade I) were observed STEMI, NSTEMI, unstable angina, DM, multiple risk factors, age > 50yrs