Morning vs. afternoon AVR may not impact 2-year mortality, rehospitalization
Procedural time of day appeared to have no influence on 2-year outcomes among intermediate-to-high-risk patients who underwent elective surgical or transcatheter aortic valve replacement, researchers reported.
According to a new analysis of the PARTNER 1 and PARTNER 2 trials, outcomes among patients who underwent elective surgical AVR or TAVR during the morning were no different compared with those operated on during the afternoon.
“Circadian rhythms influence cardiovascular physiological processes, and several experimental studies observed that tolerance to ischemia-reperfusion injury is dependent on time of day (TOD),” Flavien Vincent, MD, PhD, of the Institut Universitaire de Cardiologie et de Pneumologie de Québec at the Université Laval/Québec Heart and Lung Institute in Québec, Canada, and colleagues wrote. “TAVR eliminates the ischemia-reperfusion insult associated with cardiopulmonary bypass, but some procedural factors, such as rapid ventricular pacing, lead to reduced cardiac output and cause transient hypotension and thus could also generate myocardial ischemia. The impact of TOD on outcomes after TAVR has not been explored.”
The PARTNER 1 and 2 trials
Utilizing data from the PARTNER 1 and PARTNER 2 trials, researchers included intermediate-to-high-surgical risk patients who underwent elective TAVR (n = 4,457) or surgical AVR (n = 1,129) and stratified them based time of day of their respective procedures. Patients were sorted in the morning group if their procedures had begun between 5:00 a.m. and 11:59 a.m., while afternoon procedure were classified as starting between 12:00 p.m. and 7:00 p.m.
As Healio previously reported, balloon-expandable TAVR and surgical AVR were associated with similar 5-year outcomes among high-risk patients, with better outcomes than standard care among inoperable patients with severe aortic stenosis in the PARTNER 1 trial, while results of the PARTNER 2 trial established that TAVR was noninferior to surgical AVR among intermediate-risk patients for death or disabling stroke at 2 years.
Morning vs. afternoon AVR
For the present analysis, the primary endpoint was all-cause death or rehospitalization at 2 years.
At 2 years, researchers observed no difference in the primary endpoint among patients who underwent elective AVR during the morning compared with the afternoon, regardless of the procedure type (adjusted HR for surgical AVR = 1.08; 95% CI, 0.82-1.41; P = .58; aHR for TAVR = 1.01; 95% CI, 0.89-1.14; P = .86).
Moreover, the rates of periprocedural MI were low and similar between morning and afternoon procedures for both the surgical AVR (morning, 1.6%; afternoon, 1%; P = .51) and TAVR groups (0.4% in both groups, P = .86).
Researchers reported similar findings with regard to all other clinical endpoints.
“The main finding of this study is that there was no significant association between TOD and the composite of death or rehospitalization at either 30 days or 2 years after SAVR or TAVR interventions,” the researchers wrote. “Despite convincing data from experimental animal models, we were unable to demonstrate a circadian relationship with either TAVR or SAVR outcomes in our study.”