Cutting-edge valve and coronary trials
Trial results presented in Saturday’s Late-Breaking Science session suggest new approaches to managing asymptomatic severe aortic stenosis, transfusion strategies in patients undergoing vascular and general surgery at high risk of postoperative cardiac events, concomitant surgical ablation and combined valve and CABG surgery. Their results found that:
- Surgical aortic valve replacement improved outcomes in patients with asymptomatic severe aortic stenosis.
- A liberal postoperative transfusion strategy did not improve serious outcomes in patients with high cardiac risk compared to a restrictive strategy but may reduce heart failure and arrhythmias.
- Surgical biatrial ablation improved outcomes when compared to left atrial ablation in patients with persistent atrial fibrillation undergoing rheumatic mitral valve surgery.
- Physiology-guided coronary artery bypass grafting improved outcomes in patients undergoing valve surgery with concomitant coronary artery disease.
Early surgical aortic valve replacement improved mortality rates in patients
with asymptomatic severe aortic stenosis
For some patients with asymptomatic severe aortic stenosis, American Heart Association guidelines recommend watchful waiting with prompt intervention at symptom onset because the rate of sudden death during the asymptomatic phase is low. However, recent clinical trials have challenged the appropriateness of conservative management for such patients, demonstrating very low procedural risk of aortic valve replacement (AVR) and survival benefit of early pre-emptive AVR. The final results of Early Surgery vs. Conservative Management for Asymptomatic Severe Aortic Stenosis: Final Outcomes of the RECOVERY Trial add to the body of evidence supporting a significant benefit of early surgical AVR compared to conservative care in patients with asymptomatic severe aortic stenosis.
The multicenter parallel-group open-label trial randomly assigned 145 asymptomatic patients with severe aortic stenosis to receive early surgery (73 patients) or conservative care (72 patients) from July 2010 through April 2015 at four medical centers in Korea.
Although the trial was initially planned to complete follow-up four years after the last enrolled patient, all centers agreed to participate in extended follow-up for a minimum of 10 years. The primary endpoint was a composite of operative mortality or death from cardiovascular causes during the entire follow-up interval. Secondary endpoints included death from any cause, repeat aortic valve surgery, clinical thromboembolic events and hospitalization for heart failure during follow-up.
In the early surgery group, surgical AVR was successfully performed on all participants. All patients except four crossovers underwent surgery within two months after randomization. The median time between randomization and surgery was 23 days (interquartile range, 10 to 36). Of the 72 patients assigned to conservative care, 61 (84.7%) underwent surgical AVR (59 patients) or transcatheter AVR (two patients) during follow-up, mainly due to symptom development (49 patients). The median time from randomization to AVR was 1,048 days (interquartile range, 339 to 1,700). There was no operative mortality in either group.
In an intention-to-treat analysis, the primary endpoint occurred in two patients (2.7%) in the early surgery group and in 17 (23.6%) in the conservative-care group (HR=0.10; p=0.002). The cumulative incidence of cardiovascular mortality was 1.4% in the early surgery group vs. 18.8% at 10 years in the conservative-care group (p<0.001). A total of 11 deaths (15.1%) from any cause occurred in the early surgery group and 23 (31.9%) in the conservative care group (HR=0.42). The cumulative incidence of death from any cause was lower in the early surgery group than in the conservative-care group: 11.0% vs. 25.0% at 10 years (p=0.012).
The rate of hospitalization for heart failure was lower in the early surgery group than in the conservative care group (0% vs. 19.4%; p=0.015). Subgroup analysis according to peak aortic jet velocity (< 5.0 m/sec vs. ≥ 5.0 m/sec) revealed no significant interactions between the treatment groups and risk of cardiovascular mortality (p for interaction = 0.61) and all-cause mortality (p for interaction = 0.11).
Duk-Hyun Kang, MD, PhD
Liberal postoperative transfusion strategy did not reduce serious postoperative ischemic events in patients with high cardiac risk but may reduce heart failure
and arrhythmias
Would a liberal versus a restrictive postoperative transfusion strategy reduce the risk of death or major ischemic events in high-risk patients with underlying cardiovascular disease? That was the question researchers examined in Liberal or Restrictive Transfusion Strategy after General and Vascular Surgery: The Transfusion Trigger after Major Operations in High Cardiac Risk Patients, the TOP trial. Patients with cardiovascular disease are vulnerable to the effects of anemia, and TOP was the first trial to investigate the impact of transfusion strategy on outcomes in an exclusively high cardiac risk patient population.
The trial enrolled 1,428 veterans with baseline high cardiac risk who underwent major vascular or general surgery at 16 Veterans Affairs Medical Centers from February 2018 to March 2023. If patients’ hemoglobin level dropped below 10 g/dL postoperatively, they were randomly assigned to receive a liberal or restrictive transfusion strategy. Patients in the liberal strategy group received a transfusion if their hemoglobin dropped below 10 g/dL. In the restrictive transfusion strategy group, patients received a transfusion only if their hemoglobin dropped below 7 g/dL, which is the current guideline for most stable patients.
The primary outcome was whether the liberal strategy reduced the risk of a composite endpoint of death or major ischemic events such as myocardial infarction, stroke and acute kidney failure within 90 days after randomization, compared to the restrictive strategy.
The liberal transfusion strategy did not reduce the rate of death or major ischemic events compared to the restrictive strategy. The primary outcome occurred in 9.1% of patients in the liberal group and 10.1% in the restrictive group, a difference that was not statistically significant. However, a novel secondary outcome emerged: Patients in the restrictive group had a significantly higher rate of new arrhythmias requiring treatment and new or worsening heart failure. The composite of non-MI cardiac complications occurred in 9.9% of the restrictive group vs. 5.9% in the liberal group.
Panos Kougias, MD, MSc, FACS
New York.
Kougias noted that although the secondary finding should be confirmed in future studies, a one-size-fits-all transfusion strategy may not benefit high cardiac risk patients after major surgery. “Secondary findings in clinical trials should be interpreted carefully. However, given its strength, we should not dismiss the clinical relevance of our secondary outcome. For a specific subset of patients, such as those with a history of heart failure or who are prone to arrhythmias, clinicians may consider a more personalized approach and potentially transfuse at a moderate hemoglobin level if a patient shows early signs of cardiac strain,” he said.
Biatrial ablation provides superior rhythm control in patients with rheumatic mitral valve disease and persistent atrial fibrillation
Current guidelines recommend performing concomitant surgical ablation in patients with atrial fibrillation (AFib) undergoing mitral valve surgery (MVS) but don’t specify the optimal lesion set. As a result, there’s substantial variation in clinical practice regarding whether to perform left atrial (LA) or biatrial (BA) ablation in patients undergoing rheumatic mitral valve surgery with persistent AFib, and the safety and efficacy of these two approaches remain debated. The trial — Biatrial vs. Left Atrial Ablation During Mitral Valve Surgery for Persistent Atrial Fibrillation in Rheumatic Heart Disease — aimed to compare the effectiveness and safety of both ablation strategies in patients with persistent AFib undergoing rheumatic mitral valve surgery. The primary outcome was freedom from atrial tachyarrhythmias lasting more than 30 seconds without antiarrhythmic drugs within 12 months after surgery, excluding a three-month blanking period, assessed by scheduled Holter monitoring (24-hour at three months, three-day at six and 12 months) and symptom-triggered ECGs or Holters.
The multicenter controlled trial was conducted in 20 hospitals in China. It randomly assigned 323 patients with persistent AFib scheduled for rheumatic mitral valve surgery to either the concomitant BA or LA ablation. At 12 months, the rate of freedom from atrial tachyarrhythmias was significantly higher in the BA vs. the LA group (78.7% vs. 68.6%; difference: 10.7%; one-sided 95% CI: 3.0%; p=0.01) while freedom from permanent pacemaker implantation was noninferior in the BA group compared with the LA ablation group.
“These results demonstrate that biatrial ablation provides superior rhythm control without compromising safety,” said principal investigator Zhe Zheng, MD, PhD, a cardiologist with the National Center for Cardiovascular Diseases at Fu Wai Hospital and Institute and professor of cardiology at Peking Union Medical College and Chinese Academy of Medical Sciences in Beijing. “They may help resolve the uncertainty regarding lesion-set selection, standardize ablation practices and encourage broader adoption of biatrial ablation to achieve better rhythm outcomes in patients with persistent AFib secondary to rheumatic heart disease.”
FFR-guided revascularization improved outcomes in patients undergoing valve surgery with coronary artery disease
Physiologic guidance of coronary artery bypass grafting (CABG) during valve surgery reduced perioperative morbidity and provided sustained clinical benefits, according to findings from Angiography-Derived FFR-Guided Coronary Artery Bypass Grafting for Patients Undergoing Valve Surgery With Concomitant Coronary Artery Disease (FAVOR IV-QVAS): A Randomized Trial.
The investigator-initiated multicenter triple-blind trial enrolled 793 patients scheduled for primary valve surgery who had at least one ≥50% diameter stenosis in a major epicardial coronary vessel suitable for CABG. At 12 sites in China from 2019 to 2024, participants were randomized 1:1 to angiography-derived fractional flow reserve (angio-FFR)-guided CABG; CABG performed for lesions with angio-FFR value ≤0.80 or conventional coronary angiography (CAG)-guided CABG; CABG performed for lesions ≥50% of the coronary diameter. In the trial, angio-FFR was an AI-powered and angiography-based computational method that estimated FFR from standard angiograms.
Angio-FFR-guided CABG resulted in significantly fewer bypass grafts per patient (56% vs. 98.0%) compared with CAG-guided CABG and a lower incidence of the primary composite outcome of death, myocardial infarction, stroke, unplanned revascularization or new renal failure requiring dialysis within 30 days after surgery (7.8% vs. 13.4%; RR 0.58, p=0.01). At a mean follow-up of 30 months, the key secondary composite outcome of all-cause death, myocardial infarction, stroke, unplanned revascularization or hospitalization for unstable angina or heart failure also favored angio-FFR-guided CABG (20.7% vs. 26.8%; HR 0.74, p=0.04).
Qiang Zhao, MD
Zhao noted that coronary physiological assessment, such as FFR, quantitative flow ratio and instantaneous wave-free ratio has been widely used in practice to guide percutaneous coronary intervention with improved clinical outcomes.
“Angio-FFR may be more suitable and accurate for patients undergoing valve surgery with concomitant coronary artery disease without the need for pressure wire or pharmacologic hyperemia,” he said.
