Improvement in left ventricular diastolic stiffness induced by physical training in patients with dilated cardiomyopathy.

Background: Diastolic dysfunction in long-term heart failure is accompanied by abnormal neurohormonal control and ventricular stiffness. The diastolic phase is determined by a balance between pressure gradients and intrinsic ventricular wall properties: according to a mathematical model, the latter (ie, left ventricular [LV] elastance, K(LV)) may be calculated by the formula: K(LV) = (70/[DT-20])(2) mm Hg/mL, where DT is the transmitral Doppler deceleration time.

Methods And Results: In 54 patients with chronic systolic heart failure (39 men, 15 women; age 65 +/- 10 years; New York Heart Association [NYHA], 2.3 +/- 0.9; ejection fraction [EF], 32% +/- 5%), we analyzed the relationship between K(LV) and an index of neurohormonal derangement (levels of brain natriuretic peptide [BNP]), and investigated whether 3 months of physical training could modulate diastolic operating stiffness. Patients were randomized to physical training (n = 27) or to a control group (n = 27). Before and after training, patients underwent Doppler echocardiogram and cardiopulmonary stress test. At baseline, ventricular stiffness was related to BNP levels (P < .01). Training improved NYHA class, exercise performance, and estimated pulmonary pressure. BNP was reduced. Ventricular volumes, mean blood pressure, and EF remained unchanged. A 27% reduction of elastance was observed (K(LV), 0.111 +/- 0.044 from 0.195 +/- 0.089 mm Hg/mL; P < .01), whose magnitude was related to changes in BNP (P < .05) and to K(LV) at baseline (P < .01). No changes in K(LV) were observed in controls after 3 months (0.192 +/- 0.115 from 0.195 +/- 0.121 mm Hg/mL).

Conclusions: In heart failure, left ventricular diastolic stiffness is related to neurohormonal derangement and is modified by physical training. This improvement in LV compliance could result from a combination of hemodynamic improvement and regression of the fibrotic process.