Simple heart rate and QT parameters during stress exercise testing to assess presence and severity of stable coronary artery disease.

Aim: The relationship between QT prolongation and myocardial ischemia is well known, however not many studies have correlated corrected QT interval and heart rate recovery with the severity of coronary artery disease (CAD). Methods: This was a single-center, prospective, observational study which included 127 patients with CAD and 124 patients without CAD. Results: Corrected QT variability from peak to recovery correlated well with CAD with a p value of 0.03. Receiver operative characteristic analysis did not show any significant diagnostic accuracy with any heart rate or QT parameters for predicting the presence or severity of CAD. Conclusion: Coronary artery disease is predicted by reduced ability of the heart rate to rise from rest to peak exercise and reduced recovery of heart rate and corrected QT from peak exercise to recovery at 1 min.