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

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.

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.

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%).

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.