Predictive importance of left ventricular myocardial stiffness for the prognosis of patients with congestive heart failure

Objectives: This study was designed to determine the prognostic importance of left ventricular (LV) myocardial stiffness, a hemodynamic index which is closely related to B-type natriuretic peptide (BNP) concentration in patients with congestive heart failure (CHF).

Background: While elevated BNP, an abnormality of cardiac neurohormones, is known to be an independent marker of death or re-admission, it remains to be clarified whether there is also a strong predictor directly related to cardiac dysfunction.

Methods: LV performance variables and stress-strain analyses including diastolic myocardial stiffness constant (K(m)) were obtained from 37 patients with initial CHF by the combined simultaneous measurement of echocardiographic and hemodynamic data. Survivors were monitored for a mean of 23 months, with the main endpoint being combined death or first re-admission for CHF.

Results: Ten patients (27%) were primary endpoint cases. Both K(m) and plasma BNP levels were higher in the event than in the event-free group. By Cox proportional hazards analysis, K(m)≥4.0 was identified as the only variable with significant and independently incremental predictive power to affect the primary endpoint (adjusted hazard ratio=7.354, 95% confidence interval 1.379-39.232, p=0.02).

Conclusions: In patients with CHF, increased myocardial stiffness may have greater prognostic significance compared to other conventional predictors. Increased myocardial stiffness may be considered to be an important prognostic factor independent of the loading conditions.