Diastolic Function in Hypertension Robert A. Phillips, MD, PhD, FACC*, and Joseph A. Diamond, MD, FACC Address * Department of Medicine, Lenox Hill Hospital, 100 East 77th Street, New York, NY 10021, USA. E-mail: rphillips@lenoxhill.net Current Cardiology Reports 2001, 3:485–497 Current Science Inc. ISSN 1523-3782 Copyright © 2001 by Current Science Inc. Introduction In addition to left ventricular hypertrophy, diastolic dys- function is a major factor contributing to hypertensive heart disease and the progression to symptomatic congestive heart failure (CHF). Many antihypertensive treatments pro- mote reversal of diastolic dysfunction, which may decrease symptoms of CHF and improve survival. Adequate treat- ment of hypertension may also prevent development of CHF. A variety of techniques described herein assess dias- tolic function. The purpose of this paper is to review the following: 1) epidemiologic evidence for diastolic dysfunc- tion as a cause of CHF, 2) structural changes in the hyper- tensive heart that provide the substrate for increased diastolic dysfunction and CHF, 3) , and 4) identification and treatment of diastolic dysfunction in clinical practice. Clinical Presentation and Etiology The clinical presentation of diastolic dysfunction in hyper- tensive heart disease is variable, ranging from asymptom- atic findings on noninvasive testing, to overt CHF despite normal systolic function [1,2]. The prevalence of asymp- tomatic left ventricular (LV) filling abnormalities in adults without hypertrophy and with ambulatory awake blood pressure greater than 130/85 mm Hg may be as high as 33% [3]. Once LV hypertrophy (LVH) or ischemia devel- ops, these asymptomatic abnormalities may cause decreased exercise ejection fraction (EF), and blunt the expected rise in exercise cardiac output [4]. An estimated 30% to 45% of patients with CHF have normal systolic function but abnormal diastolic function (CHF-D) [5]. Out of 2671 asymptomatic patients with no coronary artery disease or history of heart failure in the Cardio- vascular Health Study [6•], 170 (6.4%) developed clini- cally significant CHF after up to 6 years of follow-up. Baseline echocardiograms showed normal or borderline EF (> 45%) in 96% of subjects, and in 57% at the time of presentation with heart failure. Baseline Doppler indices of diastolic function (E/A ratio) were significantly more abnormal at baseline in this group of patients that pro- gressed to clinical CHF. In a large community-based study of CHF, the prognosis for patients with diastolic heart failure was significantly diminished, being similar to patients with significant systolic dysfunction. Survival rate at 3 months, 1 year, and 5 years was 86%, 76%, and 48%, respectively (Fig. 1) [7•]. In a cohort of patients with dias- tolic dysfunction and underlying coronary artery disease, 7-year cardiovascular mortality approached 50%. Many of these patients were also hypertensive [8]. Symptoms in the presence of diastolic dysfunction are accounted for by prolonged LV relaxation or decreased compliance, which causes shifts in the diastolic LV pressure-volume relation that result in elevated left atrial and LV filling pressures [9]. The cause of fulminant pulmonary edema in these patients has been controversial. Because evaluation of LV function is usually performed after the patient’s clinical status has improved, it is not clear if diastolic function alone is the cause of the acute event. It is possible that there is transient systolic dysfunction or acute mitral regurgitation, which resolves early after initiating therapy. One clinical study, however, performed echocardiography at the time of clinical presentation, and subsequently, 1 to 3 days after clinical stabilization was achieved. LV systolic function was not decreased or significantly lower in the initial study, as compared with the follow-up study. In addition, there was no significant mitral regurgitation in the acute study [10]. However, LVEF may not be an ade- quate measure of global systolic function in the early pre- sentation of pulmonary edema. More sensitive measures of intrinsic myocardial systolic function, such as assess- ment of ventricular long axis excursion by Doppler imag- ing of the tissue, or assessment of midwall fractional shortening, may be abnormal in the acute presentation of pulmonary edema, whereas endocardial fractional short- ening remains normal [11]. Diastolic dysfunction in patients with hypertension may present as asymptomatic findings on noninvasive testing, or as fulminant pulmonary edema, despite normal left ventric- ular systolic function. Up to 40% of hypertensive patients presenting with clinical signs of congestive heart failure have normal systolic left ventricular function. In this article we review the pathophysiologic factors affecting diastolic function in individuals with diastolic function, current and emerging tools for measuring diastolic function, and cur- rent concepts regarding the treatment of patients with diastolic congestive heart failure.