Prevalence of Conduction Abnormalities in a Systolic Heart Failure Population by Race,Ethnicity, and Gender

Background : There is paucity of data regarding conduction abnormalities in the Hispanic population with systolic heart failure (HF). We aimed to evaluate the prevalence of electrocardiogram (ECG) abnormalities in a systolic HF population, with attention to the Hispanic population. Methods : A cross sectional study of 926 patients enrolled in a systolic HF disease management program. ECGS were obtained in patients with an ejection fraction (EF) ≤ 40% by echocardiography at enrollment. Univariate and multivariate analysis adjusted by ethnicities was performed. Results: White patients exhibited higher prevalence of atrial fibrillation (14.7%) than black patients (8.0%, P = 0.01) whereas Hispanics presented higher prevalence of paced rhythm (14.3% in Hispanics vs. 6.5% in whites and 5.2% in blacks, P<0.01 for both comparisons), higher prevalence of left bundle branch block (LBBB, 14.5% in Hispanics vs. 8.8% in whites and 5.8% in blacks, P = 0.002) and increased frequency of abnormal QT intervals (76.7% in Hispanics) than whites (59.6%) and blacks (69%) patients (P< 0.01 for both comparisons). A QRS interval greater than 120 ms was less prevalent among blacks (15.8% vs. 26.0% in whites and 25.3% in Hispanics, P = 0.01 for both comparisons). Univariate and multivariate analysis disclosed no influence of other characteristics (age, sex, coronary artery disease, hypertension, ejection fraction, medications) in the ECG findings. Conclusions: Hispanics with Systolic HF presented with increased prevalence of paced rhythm, LBBB, and abnormal QT intervals. Attention should be addressed to these ECG variations to recommend additional guidance for therapeutic interventions and provide important prognostic information.