The genetic variant rs1042714 (Gln27Glu) in ADBR2 gene coding for the β2 adrenergic receptor has been associated with sudden cardiac death and with ventricular arrhythmias in heart failure in previous population-based studies. We investigated whether the same polymorphism is associated with ventricular fibrillation (VF) in the context of myocardial Infarction (MI).

Patients have been recruited between 2008 and 2013 during the MAP-IDM study. Subjects included 213 patients who experienced a VF during acute phase of primary myocardial infarct and 181 controls with MI but without VF. None of the patients had other cardiac history. Patients were genotyped for the ADRB2 Gln27Glu polymorphisms by RT-PCR.

Cases and controls didn’t differ significantly in age (56.2±11.8 vs 57.4±11.4 years), in sex ratio (male 83.6% vs 83.4%), in smoker ratio (56.4% vs 58.0%) and in troponin peak value (64.2 +/-116.0 vs 70.0±78,7μg/L). Cases have a lower body mass index (BMI) (25.6±3.9 vs 26.7±4.1, p=0.01) and a lower left ventricular ejection fraction (LVEF) (45.8±11.9 vs 51.9±10.5%, p<0.0001).

In the total cohort, the Gln27Glu is in Hardy Weinberg Equilibrium (157Gln27Gln, 181 Gln27Glu, 56 Glu27Glu). Genotypes were not associated with age, gender, BMI, troponin, EF or smoking in univariate analyses.

The most interesting finding is that the delay of onset on VF in Gln27Glu cases is two times faster (73.1±105.6min) than cases carrying the Gln27Gln genotype (161.5±255.5min; p=0.004) or the Glu27Glu genotype (163.1± 314.9min; p=0.03). The Gln27Glu cases are more likely to have a VF in the 60 min after thoracic pain (OR=2.6, p=0.003).

We also show that the delay of VF is twice as fast in summer/spring period than in autumn/winter period for Gln27Gln genotype (219.2vs86.7min; p=0.02) and for Glu27Glu genotype (205.4 vs 99.6min, no significative but few samples). However, we observed that this VF delay is almost the same for Gln27Glu genotype whatever the season (84.0vs64.8min).