RESUMEN
Coronary artery disease remains an important cause of morbidity and mortality worldwide. The impact of ventricular arrhythmias and impaired cardiac vagal activity on coronary events is one of the most relevant prognostic factors, despite little research being conducted in clinical practice. A simple and cost-effective way to analyze cardiac autonomic regulation is through the heart rate turbulence (HRT) method. Studies have shown that altered HRT, which indicates reduction in the vagal cardiac activity, can identify patients who are at a higher risk of sudden death. Thus, aspects related to the definition, pathophysiological mechanism, conditions that alter the HRT behavior, and the main studies that analyzed the prognostic importance of HRT in patients with ischemic disease were discussed in this review. HRT analysis was proven to be a simple and cost-effective way to assess cardiac autonomic dysfunction by providing complementary information to classic parameters, such as the assessment of ventricular function.