Study on the factors involved in the development of coronary collaterals in hypertensive and non-hypertensive patients of coronary artery disease

Background: Coronary artery disease (CAD) results from the narrowing of coronary arteries that leads to inadequate blood supply to the heart muscles, resulting in Acute Coronary Syndrome (ACS). The coronary collaterals which develop will be an alternative source of blood flow in CAD. Myocardial ischemia stimulates the development of coronary collaterals by releasing various angiogenic growth factors, like the Vascular Endothelial Growth Factor (VEGF). Serum VEGF will serve as an important biomarker in CAD; thus, it can predict coronary collateral development. Aim: To study the factors affecting the development of coronary collaterals in hypertensive and non-hypertensive patients with CAD. Methods: The study includes 100 patients who have done coronary angiography, with an average age of 60±15. Consent was obtained from all patients, and 2 ml of blood was collected. The serum VEGF concentration and cystatin-C were quantified. Coronary Angiograms, along with other reports, were collected and analyzed. CAD was diagnosed for those with ≥ 70% stenosis inany one of the major coronary artery. Coronary collateral gradings was performed as per Rentrop Scoring system. The serum VEGF and cystatin-C levels were correlated with the collateral scores and other cardiovascular risk factors. Results: A significant correlation was found between the collateral scores and serum VEGF level in hypertensive patients only. No significant correlation was found between VEGF level, collateral scores and cardiovascular risk factors. Conclusions: Cardiovascular risk factors in turn increase the serum VEGF level, which results in collateral development. Age and sex did not show show any significant association especially old age and females, with serum VEGF levels.