Angiotensin-converting enzyme polymorphisms and their potential impact on left ventricular myocardial geometry after aortic valve surgery.

BACKGROUND AND AIM OF THE STUDY: Genetic variants of the angiotensin-converting enzyme (ACE) cascade may influence left ventricular myocardial mass (LVMM) regression after aortic valve surgery. Postoperative long-term changes in LV indices were investigated in patients with asymptomatic aortic regurgitation (AR) and symptomatic aortic stenosis (AS) and related to alleles of ACE polymorphisms.

METHODS

A total of 96 patients was included in the study, 21 with class IIa AR (22%) and 75 with class I AS (78%) recommendations for surgery. Patients were evaluated for demographic risk factors and underwent a thorough clinical examination including 3-D cardiac imaging by ultrafast-computed tomography. Genomic DNA was isolated for genotyping.

RESULTS

AR patients were younger (55.8 +/- 8.9 versus 64 +/- 9.1 years, p = 0.0014), had a larger body surface area (1.92 +/- 0.21 versus 1.82 +/- 0.19 m2, p = 0.039), and were more likely to be asymptomatic (myocardial infarction, p = 0.04; syncope, p = 0.0099; thromboembolism, p = 0.03; NYHA class IV, p = 0.04). Postoperatively, the reduction in absolute LVMM (from 297.1 +/- 52.6 to 190.1 +/- 57.1 g versus 214.4 +/- 55.7 to 143.8 +/- 40.0 g; pT = 0.0000001) and indexed LVMM (from 156.0 +/- 31.7 to 99.3 +/- 28.4 g/m2 versus 118.7 +/- 28.3 to 79.3 +/- 20.6 g/m; pT = 0.0000001) over time was more significant in AR patients, but never reached normal values. Enforced ACE inhibitor medication resulted in significantly higher postoperative indexed LVMM differences in homozygote DD patients compared to AR patients with II/ID alleles of ACE 16 ins/del polymorphism.

CONCLUSION

AR patients showed a statistically significant decrease in absolute/indexed LVMM during follow up, but never achieved LV mass recovery compared to standard values or to values in patients undergoing aortic valve replacement for AS. The benefits of ACE inhibitors were observed among AR patients with homozygote DD alleles of ACE 16 ins/del polymorphism.