Low-Sodium DASH Diet Improves Diastolic Function and Ventricular-Arterial Coupling in Hypertensive Heart Failure with Preserved Ejection Fraction
Background—Heart failure with preserved ejection fraction (HFPEF) involves failure of cardiovascular reserve in multiple domains. In HFPEF animal models, dietary sodium restriction improves ventricular and vascular stiffness and function. We hypothesized that the sodium-restricted Dietary Approaches to Stop Hypertension diet (DASH/SRD) would improve left ventricular diastolic function, arterial elastance, and ventricular-arterial (V-A) coupling in hypertensive HFPEF.
Methods and Results—Thirteen patients with treated hypertension and compensated HFPEF consumed the DASH/SRD (target sodium 50 mmol/2100 kcal) for 21 days. We measured baseline and post-DASH/SRD brachial and central BP (via radial arterial tonometry), and cardiovascular function with echocardiographic measures (all previously invasively validated). Diastolic function was quantified via the Parametrized Diastolic Filling formalism, which yields relaxation/viscoelastic (c) and passive/stiffness (k) constants through analysis of Doppler mitral inflow velocity (E-wave) contours. Effective arterial elastance (Ea) end-systolic elastance (Ees), and V-A coupling (defined as the ratio Ees:Ea) were determined using previously published techniques. Wilcoxon matched-pairs signed rank tests were used for pre-post comparisons. The DASH/SRD reduced clinic and 24-hour brachial systolic pressure (155±35 to 138±30 and 130±16 to 123±18 mmHg, both p=.02) and central end-systolic pressure trended lower (116±18 to 111±16 mmHg,p=.12). In conjunction, diastolic function improved (c, 24.3±5.3 to 22.7±8.1 s-1;p=.03; k, 252±115 to 170±37 1/s2;p=.03), Ea decreased (2.0±0.4 to 1.7±0.4 mmHg/ml;p=.007), and V-A coupling improved (Ees:Ea, 1.5±0.3 to 1.7±0.4;p=.04).
Conclusions—In hypertensive HFPEF patients, the sodium-restricted DASH diet was associated with favorable changes in ventricular diastolic function, arterial elastance, and V-A coupling.
Clinical Trial Registration—URL: http://www.clinicaltrials.gov. Unique identifier: NCT00939640.
- salt sensitivity hypertension
- preserved left ventricular function
- ventricular/vascular coupling hemodynamics
- diastolic heart failure
- Received May 8, 2013.
- Accepted August 16, 2013.