The triglyceride-glucose index, ventricular arrhythmias and major cardiovascular events in patients at high risk of sudden cardiac death.

Background: The association between the triglyceride-glucose (TyG) index and ventricular arrhythmias (VAs) is unclear. This study aimed to investigate the relationship between the TyG index, VAs, and major cardiovascular events in patients at high risk of sudden cardiac death (SCD).

Methods: We enrolled 1046 patients at high risk of SCD with an indication for implantable cardioverter-defibrillator (ICD) implantation at the Chinese National Center for Cardiovascular Diseases. The primary outcome was VAs, defined as sustained ventricular tachycardia and ventricular fibrillation documented by the ICD. The secondary outcomes were cardiac mortality, heart transplantation, and rehospitalization for heart failure.

Results: The mean (± SD) age was 59.6 ± 14.0 years old, and 25.7% were female. During the mean follow-up of 36.1 months, 342 (32.7%) patients had VAs, and 185 (17.7%) patients had major cardiovascular events. The mean fasting glucose and triglyceride levels were 111.9 ± 42.7 mg/dL and 140.0 ± 95.4 mg/L, respectively, with a TyG index range of 6.96-11.8. In the Fine-Gray subdistribution hazard model analysis, an increase in the TyG index was associated with a significant increase in the VAs (per 1 TyG index, hazard ratio [HR] 2.95; 95% confidence interval [CI], 2.29-3.80) and secondary outcome (HR 2.84; 95% CI 1.86-4.34). When stratified into tertiles, the risk of VAs was significantly higher in the highest tertile (HR 4.08; 95% CI, 2.81-5.92) than in the lowest tertile. Analysis of the secondary outcome revealed similar findings (HR 3.18; 95% CI, 1.73-5.85).

Conclusions: In our cohort, the pre-operational TyG index is significantly associated with VAs and major cardiovascular events for patients with high risk of SCD.