AIM To investigate the relationship between the insertion/deletion (I/D) polymorphism of angiotensin I converting enzyme (ACE) gene and the risk of cardiovascular events in patients with coronary heart disease after stent implantation.

METHODS This was a single-center cohort study conducted in our hospital from January 2021 to March 2022. The inclusion criteria were patients with coronary heart disease who received emergency or elective coronary stent implantation and were treated with clopidogrel 75 mg and aspirin 100mg once a day for at least one year after implantation. The patients were followed up for 12 months. ACE I/D was genotyped by TaqMan analysis and platelet aggregation was evaluated by light transmission aggregation assay. Major cardiovascular adverse events (MACE) were defined as compound events of cardiovascular death, myocardial infarction and ischemic stroke.

RESULTS During the follow-up period, a total of 44 patients experienced MACE, including 15 cases of cardiac death, 16 cases of non fatal myocardial infarction, and 13 cases of ischemic stroke. Compared with patients who did not experience MACE, patients who experienced MACE were older, had more cases of decreased left ventricular ejection fraction, fewer cases of diagnosed stable angina, and more cases of ST segment elevation acute myocardial infarction (all P<0.01). Compared with the non MACE group, the MACE group had a lower proportion of genotype II and DD, and a higher proportion of genotype ID and DD (both P<0.05）. Cox regression analysis was conducted, and the model was adjusted according to clinical covariates, including age, previous myocardial infarction, hypertension, diabetes, left ventricular ejection fraction, serum creatinine, diagnosis, low-density lipoprotein, smoking status, and previous percutaneous coronary intervention. The MACE risk of patients with ID or DD genotype is 1.99 times higher than that of patients with II genotype compared to different genotypes (adjusted for HR: 1.99, 95% CI: 1.00~3.98, P<0.05). The risk of MACE in patients with ID genotype is 2.13 times higher than that in patients with II genotype (adjusted for HR: 2.13; 95% CI: 1.10~4.12, P<0.05), while there is no significant difference in MACE risk between DD and II genotypes. Compared with genotype II, baseline and 1-month ID or DD genotype patients had higher platelet reactivity percentage values; Compared with the ID genotype, the percentage of platelet reactivity in baseline and 1-month DD genotype patients increased, all P<0.01.

CONCLUSIONS The ID genotype in ACE I/D gene polymorphism (rs4646994) is associated with increased cardiovascular risk at 1-year follow-up in patients after PCI stent implantation, and ID or DD is associated with increased platelet reactivity percentage values.