A Potentially Useful Marker to Determine Left Ventricular Dysfunction in Patients with Left Bundle Branch Block with Dilated Cardiomyopathy: Tpeak-Tend
Keywords: LBBB, dilated cardiomyopathy, Tpeak-Tend, ECG
Introduction: It has been shown in various epidemiological studies that left bundle branch block (LBBB) is an independent risk factor of cardiac mortality. In this study, we aimed to examine the relationship between left ventricular function in patients with LBBB and the Tpeak-Tend (Tp-e) interval, which can be easily measured using electrocardiography (ECG) when patients are admitted to the hospital. Patients and Methods: In this study, 56 patients with LBBB were retrospectively selected according to their echocardiographic findings by using the retrospective scanning method. In line with this selection, patients were divided into two groups: patients with ejection fraction (EF) < 50% (32.4 ± 3.7) and those with EF > 50% (58.2 ± 4.1). Tp-e/corrected Tp-e (cTp-e) intervals were measured using the surface electrocardiogram technique. Results: According to our results, a negative correlation between Tp-e and EF in patients with LBBB and dilated cardiomyopathy (DCMP) (r= -0.723, p= 0.0001). Tp-e had a positive correlation with left ventricular end-diastolic diameter (LVEDd) (r= 0.394, p= 0.035) and with left ventricular end-systolic diameter (LVESd) (r= 0.478, p= 0.009). In the correlation analysis, we observed a negative correlation between cTp-e and EF values (r= -0.649, p= 0.0001), and cTp-e had a positive correlation with LVEDd (r= 0.587, p= 0.001) as well as with LVESd (r= 0.558, p= 0.002). Conclusion: Consequently, Tp-e/cTp-e interval can be a useful parameter that can be used particularly in the determination and follow-up of the patients whose left ventricular functions have not yet been deteriorated. Furthermore, this value can be used to select patients who can benefit from the treatment and to select the optimal timing of resynchronization therapy.