Fragmented QRS in prediction of ischemic heart disease diagnosed by stress cardiovascular magnetic resonance imaging

Background: In patients with ischemic heart disease (IHD), many studies demonstrated an association between fragmented QRS complex (fQRS) on 12-lead ECG and myocardial scar, heart failure, and increased mortality. However, data in adults without history of IHD is limited. We aimed to evaluate whether there is an association between fQRS and IHD diagnosed by stress cardiac MRI. Method: We retrospectively reviewed demographic data, 12-lead ECG, and stress cardiac MRI data from 604 patients. Fragmented QRS was defined as the presence of additional R wave (R’), notching in the nadir of R or S wave, or the presence of more than one R’ in any ECG leads. Both cardiac MRI and ECG were analyzed by two independent observers. Result: Final analysis included 554 patients, 39% were male, with a mean age of 67.8 ± 11.1 years. There was positive stress cardiac MRI in 219 patients (39.5%). Older age, diabetes mellitus, and hypertension were more frequent in the positive group (p <.05). fQRS was identified in 300 patients (54.2%). Baseline characteristic did not differ significantly between patients with and without fQRS. There is an association between fQRS and IHD, OR 1.605 (95% CI 1.14–2.27), p =.007. After adjustment for age, diabetes, hypertension, renal function, and left ventricular ejection fraction, the strong association between fQRS and IHD persisted, OR 1.71 (95% CI 1.18–2.47), p =.004. Conclusion: In patients without known history of coronary artery disease, fragmented QRS is independently associated with ischemic heart disease diagnosed by stress cardiac MRI.