Effect of CRT ‘powerful and enduring’
SAN FRANCISCO — In patients with HF with reduced ejection fraction, long-term use of a cardiac resynchronization therapy defibrillator was associated with better outcomes than use of an implantable cardioverter defibrillator alone, according to the results of the After RAFT study.
“These results suggest that the effect of cardiac resynchronization therapy is both powerful and enduring,” Soori Sivakumaran, MD, associate clinical professor, faculty of medicine and dentistry, University of Alberta, Edmonton, Canada, said during a press conference at the Heart Rhythm Society Annual Scientific Sessions. “The long-term benefits of CRT come with a modest incremental procedural and complication burden.”
In the original RAFT study, which had a mean follow-up of 3.3 years, CRT-D therapy was associated with reduced HF hospitalization and mortality compared with ICD therapy in patients with NYHA class II or III HF, left ventricular EF 30% and QRS 120 millisecond or 200 millisecond paced who were on optimal medical therapy.
For After RAFT, 111 patients from the RAFT study (mean age, 66 years; 21% women) were followed long-term and all patients from the ICD group were offered crossover to CRT-D, Sivakumaran said.
The primary outcome was time to HF hospitalization, death, cardiac transplant or implantation of ventricular assist device in the intention-to-treat population. The secondary outcome was time to death, cardiac transplant or VAD implantation in the on-treatment population.
Mean overall follow-up was 7.9 years and median time to crossover to CRT-D in the ICD group was 5.3 years.
The primary outcome occurred at a mean of 7.7 years in the CRT-D group and 4.2 years in the ICD group (log-rank P = .178), according to the researchers.
During After RAFT, 32 patients crossed over from the ICD group to the CRT-D group, Sivakumaran said.
The secondary endpoint, in which the CRT-D group included those from the ICD group who crossed over and the ICD group included three patients who failed CRT-D implantation, occurred in the CRT-D group at a mean of 9.5 years and in the ICD group at a mean of 3.3 years (log-rank P < .0001), he said.
The number of additional procedures was similar in the intention-to-treat analysis but higher in the CRT-D group in the on-treatment analysis (P < .0001).
“You essentially have one more procedure if you are randomized to CRT-D in order to receive those benefits,” Sivakumaran said during the press conference.
Complication rates for the initial procedure and chronic device complications were numerically higher in the CRT-D group, but complication rates for subsequent procedures were numerically higher in the ICD group, he said. – by Erik Swain
Sivakumaran S, et al. LBCT02-03. Presented at: Heart Rhythm Society Annual Scientific Sessions; May 8-11, 2019; San Francisco.
Disclosure: The initial RAFT study was funded in part by Medtronic of Canada. Sivakumaran reports no relevant financial disclosures.