Restrictive left ventricular filling pattern as a strong predictor of depressed baroreflex sensitivity in heart failure

Background. The aim of this study was to test the hypothesis that a restrictive left ventricular diastolic filling pattern, as an index of elevated pulmonary wedge pressure, would predict a depressed baroreflex sensitivity (BRS) in patients with chronic heart failure. Methods. A total of 189 consecutive patients with an ejection fraction ≤ 40% at echocardiography, in sinus rhythm and clinically stable for at least 1 month in oral therapy, underwent clinical examination, echo-Doppler study and the phenylephrine test. Results. The correlations between the NYHA functional class, echo-Doppler variables and BRS were weak, although significant (r ranging from -0.15 to 0.40). However, patients with a deceleration time <140 ms as an expression of restrictive filling, compared to those with a deceleration time ≥ 140 ms, had a lower BRS (3 ± 4 vs 6 ± 4 ms/mmHg, p <0.00001), a lower ejection fraction (20 ± 6 vs 28 ± 7%, p <0.00001), greater left ventricular (end-diastolic volume index 137 ± 43 vs 113 ± 45 ml/m², p <0.00001) and left atrial dimensions (25 ± 6 vs 20 ± 5 cm², p <0.00001), more severe mitral regurgitation (3 ± 1 vs 2.3 ± 1, p <0.00001) and were in a higher NYHA class (2.3 ± 0.6 vs 1.8 ± 0.5, p <0.00001). Medications at the time of the study were similar in the two groups. At stepwise regression analysis, the deceleration time emerged as the most powerful independent predictor of a depressed BRS (<3 ms/mmHg), followed by mitral regurgitation, age, and NYHA class (all data p = 0.0001). Conclusions. In patients with chronic heart failure, the presence of a restrictive left ventricular filling pattern is highly predictive of autonomic derangement as expressed by low values of BRS.