The relationship between electrocardiographic characteristics,clinical features, and etiology in patients with heart failure with mildly reduced ejection fraction (HFmrEF)

Heart failure with mildly reduced ejection fraction (HFmrEF) has emerged as an important clinical entity associated with significant global mortality and morbidity. The prognostic and therapeutic value of electrocardiographic (ECG) and echocardiographic (ECHO) parameters in HFmrEF patients has been increasingly recognized. This study evaluated the relationship between ECG and ECHO parameters and clinical as well as etiological factors in HFmrEF patients. A total of 179 patients (123 males, 56 females; mean age: 64.5±12.87 years) were included. ECG parameters, including QRS duration, fragmented QRS (fQRS), Cornell Product (CP), and Electrocardiographic Diastolic Index (EDI), were analyzed. ECHO evaluations included left ventricular diastolic dysfunction (DD) and valvular pathologies. The study demonstrated that QRS duration was significantly associated with poor prognosis (104.3±18.2 ms; p=0.002), while fQRS was detected in 38% of patients and strongly correlated with adverse clinical outcomes (p=0.01). The E/e' ratio, an indicator of DD, was 12.4 ± 4.1 in the ischemic group and significantly higher (p = 0.004). Additionally, the E/e' ratio, a key marker of diastolic dysfunction, was elevated (12.8±4.1; p=0.004). The prevalence of coronary artery disease (CAD) was significantly higher in male patients (52.1%; p<0.01). The Cornell Product values were notably higher in males compared to females (1420±230 g*mV/ms; p<0.05). QRS duration, fQRS presence, E/e' ratio, and CAD prevalence were significant markers of poor prognosis in HFmrEF patients. Monitoring QRS duration and fQRS can contribute to risk stratification and guide therapeutic decisions. Moreover, echocardiographic evaluation of diastolic dysfunction underscores the importance of routine assessment for improving outcomes in HFmrEF patients. Future studies focusing on long-term clinical correlations in larger populations are warranted to validate these findings. Key Word: Heart failure with mildly reduced ejection fraction, Electrocardiography, Fragmented QRS, QRS duration, Cornell Product, Diastolic dysfunction