Background: Cardiac resynchronization therapy (CRT) is an essential treatment for patients with symptomatic heart failure and ventricular conduction abnormalities. Low-ejection-fraction (EF) cardiomyopathy often involves a wide QRS complex displaying a left bundle branch block (LBBB) morphology and markedly delayed activation of the LV lateral wall. Following CRT, patients with heart failure and LBBB have better outcomes and quality-of-life improvements. Various electrocardiographic and clinical parameters are thought to be able to predict this improvement. The Kansas City Cardiomyopathy Questionnaire (KCCQ) is a reliable tool for measuring these patients’ quality of life. Methods: This is an observational prospective study featuring over 69 individuals diagnosed with cardiac failure and dilatative cardiomyopathy with low-EF and major LBBB. This study analyzed the correlations between patient outcomes and demographic, clinical, and electrocardiographic parameters. Results: Following the analysis, we observed correlations between the QRS area, intraprocedural systolic blood pressure, Q-LV interval, the R-wave amplitude in the right precordial leads and the CRT outcomes indicated by the KCCQ score. Conclusions: The parameters found and their correlation with the KCCQ score show how CRT therapy impacts patients’ quality of life, symptom burden, and functional status.