EPIDEMIOLOGY AND CLINICAL PRESENTATION OF PATIENTS WITH ATRIAL FIBRILLATION FROM A TERTIARY CARE HOSPITAL OF EAST SIKKIM: AN OBSERVATIONAL STUDY

Abstract

OBJECTIVES: Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia encountered in clinical practice. It is a common arrhythmia and major cause of morbidity and mortality not only in the western world but in India as well. This study was conducted to find the epidemiology and clinical profile of AF patients in Sikkim. Sikkim is a small north eastern Himalayan state. Ethnicity and culture of the people is quite different from rest of India. There are various studies conducted worldwide but there is paucity of data in this region. METHODS: This observational hospital based study was carried amongst indoor and outdoor patients of AF of Department of Medicine, SMIMS, Gangtok. The diagnosis of AF was made on the basis of history, clinical examination, confirmation with 12 leads ECG and 2-DEchocardiography. Data analysis was done using micro-soft excel. Results are presented using percentages. RESULTS: Out of 51 patients of AF studied, majority of patients were aged between 71-80 years (33.33%). There were more males (54.90%) as compared to females. Structural heart disease was found in 86.26% of cases and non-structural heart disease in 13.72%. Among the structural heart disease, HTN with or without DM was seen in 50.98% cases as a cause of AF while among the non structural heart disease chronic obstructive airway (9.80 %) and thyrotoxicosis (3.92%) were most important causes. RHD was more prevalent in females (9.80%). In our study HTN was the most common etiological factor since most of our patients were in age group 61-80 yrs in which HTN is commonly seen. Dyspnea on exertion (DOE) (39.22%) was the most common presenting complaint encountered followed by palpitation (22.53%) and stroke (17.65%). Most common etiology of AF was HTN (55.55%) in patients who presented as stroke. Majority of the patients were from east district (70.58%) followed by west district (13.72%).Highest population of east district could have attributed to this. Prevalence of AF was highest in Nepalese community (68.62%) followed by bhutias (21.56%) (Table5). HTN as a risk factor was most prevalent in Nepalese (37.25%) and was a most common etiological factor in all these communities. CONCLUSIONS: This study has provided many insights on epidemiology and various presenting features of patients with AF. We have found few differences in epidemiology of AF in our studies compared to many Indian studies. In our study, majority of the patients (66.66%) were >60 yrs of age and most common etiological factor of AF was HTN followed by RHD and cardiomyopathies in contrast to most other Indian studies where presentation was more common in younger age and RHD was the most common etiology. Stroke as presenting feature was found in 17.65% patients and most common etiology of AF in these patients was HTN. This study has also discussed ethnic aspect of atrial fibrillation in this region .Most of our patients were Nepalese from ethnic point of view .This study would help in early diagnosis and prompt treatment of patients with AF especially in remote areas which remains a challenging problem. More detailed epidemiologic studies are required to improve understanding of the burden of AF and stroke in this region. INTRODUCTION: Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia encountered in clinical practice and requiring treatment. (1) It is characterized by irregular, disorganized and chaotic electrical activity of the atrium. It is a common arrhythmia and major cause of morbidity and mortality not only in the western world but in India as well. Its importance as a factor determining mortality, which it increases by 2-fold, and its relevance as a causative factor of stroke, the risk for which it increases by 5-fold, are incontrovertible and concordant in the various publications. (2) It is an independent risk factor for death with a risk ratio of 1.5for men and 1.9 for women.(3)Rheumatic valvular heart disease (RHD) continues to remain the most frequent cause of AF in a recent survey in public and private institutes in India, however as our population is aging many patients with AF have associated hypertension (HT) and ischemic heart disease (IHD).(4) In Western countries, IHD is the commonest cause of AF.(5) Diagnosis of AF is based on rapid fibrillatory waves with changing morphology and ventricular rhythm that is irregularly irregular.(6) This is clinically identified as irregularly irregular pulse with rates varying from normal to 200 and pulse deficit >10 beats. Atrial fibrillation has been classified by American Heart Association/ American college of cardiology/European Society of cardiology into first detected episode, recurrent (two or more episode), paroxysmal (terminates within 7 days), persistent (persist) for more than 7 days) and permanent (sustained for more than 1 year or has failed cardio version). (7).