Prognostic relevance of left ventricular diastolic function in patients with dilated cardiomyopathy

Patients with dilated cardiomyopathy (DCM) generally have an impaired funct ional capacity and poor long-term outcomes. A mortality of 5-15% per year h as been described actually. Aim of this study was to verify the prognostic relevance of invasive and non-invasive parameters of diastolic function in patients with DCM. In 33 patients with DCM, cardiac catheterization was performed and left ven tricular systolic (ejection fraction (EF; %)); left ventricular enddiastoli c pressure (LVEDP; mmHg) and diastolic function (time constant of relaxatio n (T, ms); the constant of myocardial stiffness (b) were derived from bipla ne laevocardiography and simultaneous micromanometric registration of press ure-volume curves. For evaluation of clinical out-come, the follow-up perio d was defined as beginning on the day after cardiac catheterization and end ing on the most recent date or with a cardiac event (death or cardiac trans plantation). All patients were reevaluated for NYHA functional class and co mpleted a standard questionnaire. The following hemodynamic parameters were evaluated: invasive parameters of left ventricular diastolic function (con stant of relaxation: tau (ms), constant of myocardial stiffness: b)), as we ll as parameters of systolic function (ejection fraction (EF; %)), left ven tricular pressure (LVEDP; mmHg), left ventricular muscle mass index (LVMMI; g/m(2)), left ventricular enddiastolic volume index (LVEDVI; ml/m(2)) and noninvasive parameters of morphological data, left ventricular systolic (fr actional shortening (FS, %) and ejection fraction) and diastolic parameters with echocardiography. During the follow-up period of 36 months, 11 of 33 patients experienced a m ajor cardiac event (cardiac death n = 8, heart transplantion n = 3). The ma jor cause of death was progressive pump failure. The remaining 22 patients were further classified with respect to changes in functional status. While clinical symptoms could be improved medically in patients with moderate in crease of myocardial stiffness, patients with severe increase of myocardial stiffness (b: 76.1 +/- 12.1 vs 17.9 +/- +8.1, p< 0.001) could not be impro ved and suffered more cardiac events. Doppler echocardiographic measurement s in these patients showed a restrictive filling pattern (V-E 0.91 +/- 0.21 vs 0.64 +/- 0.18 m/s; p < 0.01; VA 0.52 +/- 0.23 vs 0.57 +/- 0.24 m/s; p < 0.01, deceleration time 129 +/- 17 vs 211 +/- 14 ms; p< 0.01). The medical heart failure therapy was comparable in both groups. In patients with cardiac events, the diastolic left ventricular variables d id not significantly differ between patients who underwent heart transplant ation and those who died. Patients who demonstrated a sole impairment of re laxation (tau: > 50 ms) suffered no cardiac events. Impaired diastolic function contributes to the clinical picture of congesti ve heart failure. Parameters of left ventricular diastolic function are pow erful and important predictors of major cardiac events in patients with DCM , like heart transplantion and non-sudden death, and may indicate future cl inical success of medical treatment. Invasive and non-invasive parameters o f diastolic function reveal comparable information for the estimation of pr ognosis of patients with DCM in order to initiate early therapy.