Prognostic Importance of Diastolic Function and Filling Pressure in Patients With Acute Myocardial Infarction

Abstract

Acute myocardial infarction (AMI) is characterized by regional myocardial damage that may lead to systolic and diastolic dysfunction with a subsequent risk of left ventricular (LV) remodeling, local and systemic neurohormonal activation, and vascular dysfunction. The pathophysiology and prognosis of LV systolic dysfunction after AMI have been the focus of research for several decades. Insights from these studies have led to several therapeutic interventions that improve outcome. In addition to depressed systolic function, clinical or radiographic evidence of heart failure is a consistent and powerful predictor of outcome in patients after AMI.1 Pulmonary congestion after infarction reflects raised LV filling pressures but is frequently seen after what appears to be only minor myocardial damage.2 The pathophysiological mechanism for this is incompletely understood but may involve impaired active relaxation of the myocardium and increased LV chamber stiffness and hence abnormalities in diastolic function. If these are to be determined directly, cardiac catheterization with assessment of pressure-volume relationships with the use of high-fidelity micromanometer catheters is required. This highly specialized approach is not suitable for daily clinical practice. Likewise, although direct measurements of right heart or LV end-diastolic pressure are important predictors of adverse outcome after AMI in selected populations,3,4 the risk of complications precludes routine use of indwelling catheters in all patients. There has therefore been considerable interest in using noninvasive estimates of diastolic function, particularly Doppler echocardiographic assessment of LV filling dynamics and, more recently, the volume of the left atrium (LA), to predict outcome in patients with AMI. The objective of this review is to summarize the current understanding of abnormal LV filling in the early phase after AMI with focus on the complementary prognostic information that may be gained by assessment of LV filling dynamics and LA volume with the use of 2-dimensional and Doppler …