Association of seven renin angiotensin system gene polymorphisms with restenosis in patients following coronary stenting

BACKGROUND AND OBJECTIVE Percutaneous coronary intervention, despite being effective for coronary revascularization, causes in-stent restenosis due to neointimal hyperplasia in a large number of patients. The renin-angiotensin system is involved in neointimal hyperplasia. This study sought to evaluate seven gene polymorphisms of key renin-angiotensin system components, including angiotensinogen, angiotensin-converting enzyme and angiotensin II type 1a receptors, and their associations with in-stent restenosis in patients with coronary artery disease following coronary stenting. METHODS AND RESULTS Three hundred and fifty-two patients undergoing coronary drug-eluting stent implantation were recruited. Seventy-five patients (21.3%) were diagnosed as restenosis by angiography. Genotyping for angiotensin-converting enzyme insertion/deletion demonstrated a significant association of angiotensin-converting enzyme DD genotype with the occurrence of restenosis. Direct DNA sequencing revealed no association of angiotensinogen (M235T, G217A, G152A, G-6A, and A-20C) or angiotensin II type I receptor A1166C polymorphisms with in-stent restenosis. However, angiotensin II type 1a A1166C polymorphism was significantly associated with increased susceptibility to restenosis in a subgroup of patients aged more than 60 years. CONCLUSION Thus, our study suggests that genetic polymorphisms of angiotensin-converting enzyme insertion/deletion are associated with in-stent restenosis in coronary artery disease patients following coronary stenting.