The role of genetics in coronary artery bypass surgery patients under 30 years of age

ABSTRACT

Aim: We undertook genetic assessment of coronary artery disease (CAD) in 20 patients aged 30 years or less undergoing coronary artery bypass grafting (CABG) surgery, to investigate the prognostic value of pre-defined genes.Methods: Twenty patients, who underwent CABG surgery between December 2001 and May 2013, were retrospectively analysed to find out the role their genetic make-up played in their disease. We used three genetic diagnostic tests, the plasminogen activator inhibitor (PAI)-1 gene, the A1/A2 polymorphism of glycoprotein IIIa (GpIIIa) gene, and common polymorphisms of the methylenetetrahydrofolate reductase (MTHFR) gene.Results: The mean age of patients was 26.35 ± 3.51 (19­30) years, and 90% were male (n = 18). One patient had diabetes, three had hypertension, 11 (55%) had dyslipidaemia and 16 (80%) were smokers. Eight of the patients (40%) had left ventricular ejection fraction (LVEF) < 50%, and functional capacity was poor in only two (10%) patients (NYHA III­ IV). Follow up was completed in all patients (100%). We found five homozygous and 11 heterozygous mutations in the MTHFR gene, which predisposes individuals to coronary artery disease or deep-vein thrombosis. Eight patients were found to have a GpIIIa gene polymorphism, which is associated with increased risk of myocardial infarction (MI). Fifteen patients had a polymorphism in the promoter region of the PAI-1 gene, which is a major inhibitor of the fibrinolytic system. Conclusion: MTHFR C677T polymorphism, and GpIIIa and PAI-1 genes are risk factors for CAD. In young patients, genetic studies promise to revolutionise early diagnosis, treatment and prevention of CAD and MI