Pulmonary Venous Flow Pattern and Atrial Fibrillation: Fact and Controversy

Abstract

The role of echocardiography in patients with atrial fibrillation (AF) has been changing gradually according with recent advance in echocardiographic instruments and better understanding for AF. Historically, M-mode echocardiography applied to AF patients has focused on the diagnosis of underlying organic heart diseases and on the detection of left atrial (LA) thrombi. These are not surprising because AF had been the highest risk of ischemic stroke in the era of incomplete anticoagulation therapy. Thereafter, LA size, volume and functions have been foci assessed by echocardiography. These echocardiographic procedures have been conducted for prediction and prevention of recurrence of AF paroxysms (Barbier et al, 1994; Verdecchia et al, 2003; Vasan et al, 2003). Spontaneous echo contrast has also been an established B-mode echocardiographic finding with highly predictive value of ischemic stroke. After the development of Doppler echocardiography, pulmonary venous flow (PVF) evaluation is a routine laboratory investigation for patients with and without AF. The usefulness of PVF evaluation is not limited to assess LA or left ventricular (LV) functions, but has expanded to investigation of various aspects of AF (Tabata et al., 2003). PVF recording increases its usefulness when it is combined with recordings of Doppler LV inflow pattern. This article reviews the established usefulness of PVF estimation in patients with permanent AF, and then focuses on the potential usefulness of PVF assessment in AF progression, i.e., during sinus rhythm (i.e., interval of paroxysms of AF), during ongoing paroxysmal AF, and further during the longterm AF management.