Atrial Fibrillation: The Most Common Complication of Rheumatic Mitral Stenosis

Rheumatic heart disease (RHD) is a condition caused by repeated episodes of rheumatic fever that damage the heart valves. The most commonly affected valves include the mitral, tricuspid, and aortic valves. Among these, mitral stenosis—narrowing of the mitral valve—is particularly associated with several complications, with atrial fibrillation (AFib) being the most frequent.

Understanding Atrial Fibrillation in Mitral Stenosis

Atrial fibrillation is often one of the earliest complications of rheumatic mitral stenosis and can even be the initial symptom that leads patients to seek medical attention. The condition develops due to increased pressure in the left atrium, which causes the chamber to enlarge and the atrial walls to undergo fibrosis. These structural changes create a favorable environment for the onset and persistence of AFib.

Impact of Atrial Fibrillation on Heart Function

When AFib occurs, the normal electrical activity of the heart becomes irregular, leading to chaotic and often rapid heart rhythms. This disrupts the coordinated filling of the ventricles during diastole, significantly reducing the efficiency of the heart's pumping action. As a result, cardiac output can drop by as much as 20–25%, especially if the ventricular rate is uncontrolled.

Clinical Consequences of AFib in RHD Patients

This decline in cardiac performance can lead to worsening heart failure, sudden breathlessness, and in severe cases, acute pulmonary edema. These symptoms not only reduce quality of life but also increase the risk of hospitalization and mortality if not managed promptly.

Importance of Early Detection and Management

Given its prevalence and potential for serious complications, early detection and appropriate management of AFib are crucial in patients with rheumatic mitral stenosis. Treatment strategies may include rate or rhythm control, anticoagulation to prevent stroke, and interventions aimed at improving valve function such as balloon valvuloplasty or surgical repair.

In conclusion, atrial fibrillation is the most common complication associated with rheumatic mitral valve stenosis. Recognizing its impact on cardiac function and initiating timely intervention can significantly improve patient outcomes and reduce the risk of life-threatening events.