Diastolic dysfunction: a link between hypertension and heart failure

Abstract

Diastolic heart failure is characterized by the symptoms and signs of heart failure, a preserved ejection fraction and abnormal left ventricular (LV) diastolic function caused by a decreased LV compliance and relaxation. The signs and symptoms of diastolic heart failure are indistinguishable from those of heart failure related to systolic dysfunction; therefore, the diagnosis of diastolic heart failure is often one of exclusion. The majority of patients with heart failure and preserved ejection fraction have a history of hypertension. Hypertension induces a compensatory thickening of the ventricular wall in an attempt to normalize wall stress, which results in LV concentric hypertrophy, which in turn decreases LV compliance and LV diastolic filling. There is an abnormal accumulation of fibrillar collagen accompanying the hypertension-induced LV hypertrophy, which is also associated with decreased compliance and LV diastolic dysfunction. There are no specific guidelines for treating diastolic heart failure, but pharmacological treatment should be directed at normalizing blood pressure, promoting regression of LV hypertrophy, preventing tachycardia and treating symptoms of congestion. Preventive strategies directed toward an early and aggressive blood pressure control are likely to offer the greatest promise for reducing the incidence of diastolic heart failure.

Fig. 1

The filling phase of the cardiac cycle moves along the end-diastolic pressure-volume relationship or passive filling curve of the ventricle. A shift of the curve from A to B indicates that a higher LV pressure is required to distend the left ventricle to a similar volume, in this case from 100 to 120 ml. Modified with permission from Little, W.C., Downes, T.R. Clinical evaluation of left ventricular diastolic performance. Prog Cardiovasc Dis 1990, 32(4): 273−90. Copyright 1990 Elsevier Ltd. All rights reserved.

Fig. 2

Doppler measurement of mitral inflow velocity of A) impaired, B) pseudonormal and C) restrictive filling patterns. Modified with permission from Sohn, D.W., Chai, I.H., Lee, D.J. et al. Assessment of mitral annulus velocity by Doppler tissue imaging in the evaluation of left ventricular diastolic function. J Am Coll Cardiol 1997, 30(2). 474–80. Copyright 1997 Elsevier Ltd. All rights reserved.

Fig. 3

For any given LV filling pressure (end-diastolic pressure: EDP), the greater the afterload, the less the stroke volume. As filling pressure is raised, the flow and volume displaced from the chamber increases for any given ejection pressures. With permission from Weber, K.T., Janicki, J.S., Hunter, W.C., Shroff, S., Pearlman, E.S., Fishman, A.P. The contractile behavior of the heart and its functional coupling to the circulation. Prog Cardiovasc Dis 1982, 24(5): 375–400. Copyright 1982 Elsevier Ltd. All rights reserved.

Fig. 4

Gas exchange during exercise in patients with primarily systolic dysfunction (SysD), isolated diastolic dysfunction (DiaD) and in healthy normals (NL). Patients with DiaD and SysD had an elevated V_E/VCO₂ at rest and during exercise relative to NL subjects (P < 0.05), while patients with DiaD only had elevated values at rest and light exercise relative to patients with SysD (P < 0.05). With permission from Arruda, A.L., Pellikka, P.A., Olson, T.P., Johnson, B.D. Exercise capacity, breathing pattern, and gas exchange during exercise for patients with isolated diastolic dysfunction. J Am Soc Echocardiogr 2007, 20(7): 838–46. Copyright 2007 Elsevier Ltd. All rights reserved.