Doenças Cardiovasculares e Diagnóstico

Left Atrial Slow Flow and Its Potential Complication

Abstract

Suthipong Soontrapa, Ralph Paone, Leigh Ann Jenkins, Gary Meyerrose and Aliakbar Arvandi

It has been estimated that 2.2 million people in United States have paroxysmal or persistent atrial fibrillation. The incidence has increased 13% over the past 20 years and it seems to be on the rise. The most feared complication of atrial fibrillation is systemic thromboembolic events. Mitral stenosis and atrial fibrillation is risk factors for cardiac thrombus formation. We report an interesting case in which a 69-year-old male with rheumatic mitral stenosis, atrial fibrillation and congestive heart failure developed rapidly worsening dyspnea on anticoagulation. Subsequent investigation demonstrated impaired left ventricular systolic function, severe mitral valve stenosis and a large left atrial thrombus.

Since the patient’s symptoms had worsened rapidly during a relatively short period of time, we hypothesize that the thrombus was obstructing blood flow through the left atrium and was causing the patient’s symptoms. Mitral valve stenosis, itself, is a risk factor for thromboembolic events. Combined with atrial fibrillation and left ventricular systolic dysfunction, slow flow in the left atrium may contribute to thrombus formation.

Even though, our patient was anticoagulated, the stability of oral anticoagulation therapy is essential. We want to highlight one particular group of patients, classified as high risk, in which close clinical follow-up and more intense anticoagulation might be of benefit. Also, the possibility of thrombus formation in the left atrium should be considered when there is a sudden change in symptoms