Prevalence and correlates of electrocardiographic indications for invasive cardiac procedures among patients with reduced ejection fraction heart failure in Western Kenya

Abstract

Background: Heart failure is a heterogeneous and life-threatening syndrome that affects more than 26 million individuals globally. The phenotype Heart Failure with reduced Ejection Fraction (HFrEF) contributes to 60% of all diagnosed cases. Despite the use of Guideline Directed Medical Therapy, a number of HFrEF patients remain symptomatic with a high risk of death. Electrocardiographic abnormalities are more prevalent in HFrEF and associated with poorer outcomes. However, improved outcomes following invasive cardiac procedures have been demonstrated in patients with pathological “Q” waves, clinically significant arrhythmias and prolonged QRS duration. These procedures include coronary angiography with or without revascularization, Cardiac Resynchronization Therapy, Implantable Cardioverter Defibrillators and Pacemaker implantation. This study aimed at determining the prevalence and describing the correlates of patients who can potentially benefit from Invasive cardiac procedures. Objectives: To determine the prevalence and correlates of pathological “Q” waves, prolonged QRS and clinically significant arrhythmias in HFrEF patients. Methods: A cross-sectional study was conducted between July and November 2023 at MTRH medical wards, CCU and cardiology clinics. Recruitment of 243 participants above eighteen years with current clinical echocardiogram of ≤6 months used to identify HFrEF (Left Ventricular Ejection Fraction ≤40%) were consented and underwent 12 lead electrocardiograms recording. Prevalence of pre-specified electrocardiogram abnormalities was calculated and correlates namely older age, body mass index, documented hypertension, diabetes and renal dysfunction analyzed. Bivariate associations were tested using chi square for categorical variables, one sample t- test for continuous variables and multivariate associations - logistic regression Results: Participants had a mean age of 60 years and females predominated 137(56.4%). Those with abnormal electrocardiogram were 143(58.8%) with prolonged QRS being the commonest 62(25.5%) and LBBB morphology constituting the most subtype. Clinically significant arrythmias were 48(19.8%) with atrial fibrillation dominating. The least prevalent indication was pathological Q waves at 33(13.6%). More than a third were overweight 91(37%) and hypertension was the commonest comorbidity 132(54.3%). Using logistic regression, older age and being overweight were associated with studied electrocardiogram abnormalities with p- values <0.001 and 0.035 respectively. Conclusion Over half of study participants had at least one electrocardiographic indication for invasive cardiac procedures on the basis of prolonged QRS, pathological Q waves or clinically significant arrythmias. Being elderly and overweight were significantly associated with indications for invasive cardiac procedures. Recommendation Close monitoring should be done for the elderly and weight management for those with cardiovascular diseases. Secondly, further studies to explore the uptake of invasive cardiac procedures and examine the long-term benefits in view of the quality of life and mortality.