[Relationship between angiotensin-1 converting enzyme gene polymorphism and in-stent restenosis]

To investigate the relationship between angiotensin-1 converting enzyme (ACE) genotype and the incidence of in-stent restenosis (ISR).

One hundred and twenty eight patients, native of northeast China and of Han nationality, underwent coronary stenting consecutively from 1997 to 2000 and were followed up for 3 months to 2 years. They were divided into two groups according to the degree of stenosis of arterial lumen diagnosed during the second coronary angiography: ISR group (n = 43, with the lumen of stenting area stenosed by more than half of the diameter of the original lumen) and non-ISR group (n = 85, with the stenosis less than half of the diameter of original lumen). DNA of peripheral white blood cells was collected and ACE genotype was analyzed by PCR method. The demographic data, medical history, and body mass index of the patients were recorded. The cholesterol, triglycerin, blood sugar, systolic pressure, and diastolic pressure were examined 24 hours before stenting.

More patients with type II diabetes were found in the ISR group than in the NISR group (P < 0.025). No difference in other clinical and biochemical indexes was found between these two groups (P > 0.05). The frequencies of DD, ID and II were 0.651, 0.163, and 0.186 respectively in ISR patients, and were 0.412, 0.282, and 0.305 respectively in NISR group. The restenosis rate was significantly higher in patients with ACD DD genotype than in patients with ID or II genotypes (P < 0.025). The frequency of D allele (73.26%) was significantly higher than that of I allele (26.74%) (P < 0.01).

ACE polymorphisms are associated with ISR. The D alleles might be a risk factor for ISR.