Background: Risk stratification in patients with congestive heart failure (CHF) is an obligatory part of the heart transplantation (HTx) selection process. New medical therapies and the predictive value of hemodynamic changes over time have not been adequately taken into account in previous stratification models. In this study we assessed the prognostic value of 55 variables at baseline and 9 variables representing changes of hemodynamic parameters over time.
Methods: A total of 178 patients with CHF were examined on 3.4 +/- 2.6 occasions (mean follow-up 19 +/- 19 months). Using the Cox proportional hazards model, univariate and multivariate relative risks (RRs) with 95% confidence intervals (CI) were determined for predicting event-free survival. A prognostic score (Munich score) was derived from the multivariate Cox model and three risk groups were derived.
Results: During follow-up, 23 patients (13%) died and 63 (35%) underwent HTx. The univariate analysis yielded 21 statistically significant (p < 0.05) predictors of event-free survival. However, only four baseline variables (etiology of ischemic cardiomyopathy, systolic blood pressure, left ventricular [LV] end-diastolic diameter, maximal workload) and the change over 12 months in fractional shortening remained statistically significant (p < 0.05) in the multivariate Cox model and were used for the prognostic score. Within 12 months, no event occurred in the low-risk group, 8.1% in the intermediate, and 30.1% in the high-risk group.
Conclusions: The incorporation of changes over time in hemodynamic parameters allowed for an improved baseline risk stratification model for the HTx selection process, especially in the era of new medical therapies such as beta-blocker therapy. All significant variables of the Munich score can be obtained in routinely performed non-invasive tests.