Prevalence and Factors Associated with Atrial Fibrillation Among Patients with Rheumatic Heart Disease.

Introduction: Rheumatic heart disease (RHD) is one of the common causes of atrial fibrillation (AF) is associated with significant morbidity and mortality. There is a lack of data on the prevalence of AF and factors associated with increased risk of AF in patients with RHD from Nepal.

Methods: A total of 120 patients who received care at Nobel Medical College Teaching Hospital from January 2018 to February 2019 with a diagnosis of RHD with AF were enrolled. Demographic information, relevant clinical and laboratory parameters and predisposing conditions for AF were obtained from a structured questionnaire designed.

Results: The prevalence of AF was 120 (36.3%) out of 330 cases of RHD screened. The male to female ratio was 32:88. The mean age was 50.2 (range 22-80) years. Prevalence was slightly more in females (36.9%) as compared to males (34.7 %). The prevalence of AF in patients with predominant mitral stenosis (MS) was 66.6% and less in patients with predominant mitral regurgitation (MR) (16.6%). The prevalence of AF in cases of MS with mitral valve area (MVA) < 1.5 cm2 was 76.2% as compared to 23.7% in cases with MVA > 1.5 cm2. Mitral valve (MV) was the most commonly affected valve (83.3%) followed by the aortic valve (10%). Both mitral and aortic valves were involved in 6.6% of patients. Majority of patients (97.5%) had enlarged left atrium (>40mm), reduced estimated glomerular filtration rate (eGFR) of <90 ml/min (85.8%). Patients of RHD with AF were complicated with decreased left ventricular (LV) systolic function (67.5%), pulmonary artery hypertension (52.5%), left atrial clot (9.1%), stroke (8.3%), and peripheral embolism (2.5%).

Conclusions: AF is a common rhythm disorder in patients with RHD. Prevalence of AF is common in females, increases with age, increasing LA size, increased severity of MS and decreased level of eGFR.