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Paced or sensed conduction time to determine programming with cardiac resynchronization therapy: The PASED-CRT Trial
Raffaele Corbisiero1, JoEllen Schmidt1, David Muller2
1Deborah Heart & Lung Center, Browns Mills, New Jersey, USA.
Background:
Cardiac resynchronization therapy (CRT) is a well-established treatment for patients with drug refractory heart failure.
Objectives:
This study sought to compare the longest RVsense to LVsense activation time (sLAT) versus the longest RVpace to LVsense activation time (pLAT) as the programmed site for left ventricular (LV) pacing in CRT patients with quadripolar LV leads at 3 months.
Methods:
This single site, double-blinded, prospective trial, randomized patients 1:1 into the sLAT or pLAT group to determine response. LV pacing was programmed at implant and maintained through 3 months of follow-up. The 6-minute hall walk (6MHW) test, NYHA, Minnesota living with heart failure, and clinical composite score (CCS) at the 3 months was compared.
Results:
N = 92 patients (73M:19F age 66 ± 11.3 years) were randomized implanted and programmed per protocol. Baseline characteristics were comparable. N = 39 sLAT and N = 34 pLAT completed the 3-month visit for final analysis. Significant improvement from baseline to 3 months was seen in the sLAT group from 253.9 (+/-11.5) to 323.1 (+/-11.9) P = .001. Similarly, the pLAT group improved from 274.9 (+/-16.15) to 343.9 (+/-15.9) P = .003. The difference between these groups, however, did not reach significance (P = .86). The pLAT group demonstrated a higher responder rate of (71%) versus the sLAT group (64%) based on the CCS although not reaching significance (P = .56).
Conclusions:
Use of both the pLAT and sLAT method of programming demonstrated significant improvement in 6MHW distance at 3 months with pLAT demonstrating a slightly higher responder rate based on CCS (P = .56). pLAT should be considered at minimum as equivalent in patients with no intrinsic conduction.
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