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

AimsThe 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 resultsThis 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 followup 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 ¼ 0.018) and during CRT (894 + 224 vs. 985 + 244 mmHg/s, P ¼ 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 ¼ 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 ¼ 0.012] and HR 0.846 (95% CI 0.723-0.991, P ¼ 0.038), respectively. ConclusionLeft 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.--

Transseptal Conduction as an Important Determinant for Cardiac Resynchronization Therapy, as Revealed by Extensive Electrical Mapping in the Dyssynchronous Canine Heart

“…This study investigated acute hemodynamic improvement although these effects may not (completely) translate into chronic outcome. 30 However, the GREATER-EARTH trial reported no differences in reverse remodeling between pacing modalities after 6 months, suggesting that acute similarities may persist into the chronic phase. …”

Interplay of Electrical Wavefronts as Determinant of the Response to Cardiac Resynchronization Therapy in Dyssynchronous Canine Hearts

“…Acute response may not always predict chronic outcome. 24 Moreover, the dog models may not recapitulate all characteristics of dyssynchronous heart failure and LBBB occurring in patients. The canine model used is representative of nonischemic LBBB hearts in patients, but may not reflect all abnormalities present in patients with ischemic hearts.…”

Acute contractile recovery extent during biventricular pacing is not associated with follow-up in patients undergoing resynchronization

“…In any case, it remains unclear whether a response to early surrogate testing would identify the chronic responders to CRT with respect to hard clinical end points [25]. This reasoning is in line with another report that described how the acute improvement in dP/dt max was not correlated to the clinical outcome, although dP/dt max , measured at baseline and during CRT, was a predictor of 1-year survival free from mortality, heart transplantation, or LV assist device implantation [26]. Thus, it might be that the acute response in contractility, in our study as well as in other studies, might have been a measure of response to CRT than an indicator of prognosis per se.…”