Baseline left ventricular dP/dt max rather than the acute improvement in dP/dt max predicts clinical outcome in patients with cardiac resynchronization therapy

Abstract

Aims: The maximum rate of left ventricular (LV) pressure rise (dP/dt max) has been used to assess the acute haemodynamic effect of cardiac resynchronization therapy (CRT). We tested the hypothesis that LV dP/dt max predicts long-term clinical outcome after initiation of CRT. Methods and results: This was a retrospective observational multicentre study in 285 patients in whom dP/dt max was measured invasively following implantation of a CRT device. The minimum required follow-up was 1 year. We analysed the relationship between dP/dt max and time to the composite endpoint, consisting of all-cause mortality, heart transplantation (HTX), or LV assist device (LVAD) implantation within the first year of CRT. Thirty-four events occurred after a mean follow-up of 160 days (range 21-359). Patients with an event had lower dP/dt max than patients without an event both at baseline (705 ± 194 vs. 800 ± 222 mmHg/s, P = 0.018) and during CRT (894 ± 224 vs. 985 ± 244 mmHg/s, P = 0.033), but the acute increase in dP/dt max was similar in patients with and without an event (190 ± 133 vs. 185 ± 115 mmHg/s, P n.s.). Left ventricular dP/dt max-level at baseline and during CRT both predicted the clinical outcome after adjustment for gender, aetiology and New York Heart Association class: hazard ratio (HR) 0.791 [95 confidence interval (CI) 0.658-0.950, P = 0.012] and HR 0.846 (95 CI 0.723-0.991, P = 0.038), respectively. Conclusion: Left ventricular dP/dt max measured at baseline and during CRT are predictors of 1-year survival free from all-cause mortality, HTX, or LVAD implantation, but the acute improvement in dP/dt max is not correlated to clinical outcome. © The Author 2011.