Many Young Patients With AR Do Not Achieve LV Normalization With Surgery

Up to one-third of young adults with aortic regurgitation (AR) treated with valve replacement or repair do not achieve postsurgical normalization of left ventricular size and function, suggesting that interventions may need to occur earlier.

In the single-center study of patients under the age of 41 who primarily had congenital heart disease, those who met guideline criteria for aortic valve surgery were less likely to normalize their LV postoperatively than those who had the surgery without meeting the criteria.

Other predictors of not normalizing LV after surgery were higher presurgical LV end-systolic diameter and having had a prior thoracic surgery.

“These observations have clinical implications, because postoperative LV characteristics were strongly associated with the risk of death or heart failure during follow-up,” write Ana Barradas-Pires, MD (Royal Brompton Hospital, Guy’s and St Thomas’ NHS Foundation Trust, London, England).

They add that AR is a major challenge in these patients, “because there is a need to balance the short-and long-term benefits of surgery against the potential perioperative and long-term complications, as well as a need to minimize the number of surgeries that a patient undergoes throughout their lifetime.”

In the study, published in the Journal of the American Heart Association, approximately one in five patients experienced a valve-related complication.

“A key point of this paper is that we're recognizing that aortic regurgitation is not benign,” said Gilbert Tang, MD, MBA (Mount Sinai Health System, New York, NY), who commented on the study for TCTMD. Also, he noted, “it is often under- or misdiagnosed.”

Part of the problem contributing to that is that the leak may be difficult to see on the transthoracic echocardiogram (TTE).

“You often have to do a transesophageal echo to be able to see that better and characterize the pathology,” he added. In many cases, patients may be told that their AR is moderate when it may actually be severe. As a result, by the time they present for surgery, underlying cardiac damage may have already occurred. While some can recover from it, others may not be so lucky.

“What they are really saying in this paper is that there is a tipping point . . . and we don't really know what the tipping point is because obviously it depends on the individual, but when you reach it then it’ll be much harder for the heart to recover even if you fixed the aortic regurgitation,” Tang said.

High Freedom From Reintervention Rates

For the study, Barradas-Pires and colleagues retrospectively analyzed outcomes in 172 adults (median age 29 years; 19% female) who underwent valve replacement or repair for at least moderate AR at a single tertiary center in the United Kingdom between 2005 and 2019. The majority of patients had congenital heart disease, and approximately 77% had a bicuspid aortic valve. More than half had at least one previous sternotomy, 10.5% had a previous thoracotomy, and 32% had a prior aortic valve intervention. The incidence of chronic AR at the time of intervention was 92.5%. The primary surgical indication was progressive LV dilatation and/or dysfunction in more than 90%.

Only about 45% of patients were symptomatic at the time of surgery, with 35.8% not fulfilling the 2021 European Society of Cardiology/European Association for Cardio-Thoracic Surgery guideline recommendations for surgery and 27% not satisfying the 2020 American College of Cardiology/American Heart Association guideline indications.

Nearly 60% of patients received a biological prosthesis, 24% a mechanical prosthesis, and 12.8% a Ross procedure.

I think we need to have a bit of a campaign to educate the whole medical community to diagnose these patients earlier rather than later. Gilbert Tang

Normalization of LV size and function at least 6 months after surgery, the primary composite outcome, was achieved in 65% of patients.  Having a higher presurgical LV end-systolic diameter correlated with failure to normalize LV function (OR 2.81 per 1-cm increase; 95% CI 1.54-5.56). The baseline LV end-systolic diameter cutoff for predicting lack of LV normalization was 43 mm.

Only 9.3% of patients experienced residual symptoms, which were primarily mild.

Over a median 5.6 years of follow-up, 22.1% of patients experienced at least one major clinical event, 2.9% died, 5.8% had new heart failure, and one patient was referred for heart transplantation. At least one episode of infective endocarditis occurred in 6.4%. In nearly half of those cases, the infection occurred within a year of the index operation. Overall, rates of freedom from aortic reintervention were 98% at 1 year, 96.5% at 5 years, and 85.4% at 10 years.

Getting the Timing Right

Barradas-Pires and colleagues say further studies are needed to identify the optimal timing for aortic valve surgery. This is where a validated risk score that incorporates the benefits of early intervention, the risks of surgery, and the likelihood of complications would be helpful.

“Because younger patients tend to prefer biological valves due to lifestyle considerations, vigilance is required to promptly detect and manage prosthetic valve complications,” they add. “The new and evolving era of transcatheter aortic valve implantation might present an alternative strategy for patients requiring redo surgery following conventional aortic valve replacement in the future.”

One example of that new and evolving technology will be shown in ALIGN-AR, which is scheduled to be presented as a late breaking trial at TCT 2023. The study is looking at TAVI with the JenaValve Trilogy (JenaValve) in high-risk patients with symptomatic severe native aortic regurgitation.

“If it's positive, it's going to bring a lot of momentum and excitement to intervening on these patients who are considered high risk for surgery,” Tang noted.

Despite the obvious limitation of being a small, single-center study, Tang said the data from Barradas-Pires and colleagues are “a call to arms” to diagnose and treat earlier.

“This needs to be picked up more broadly by educating pediatricians and primary care physicians, he added. “Some of these younger patients don’t have a primary care doctor and present first to an urgent care. So, I think we need to have a bit of a campaign to educate the whole medical community to diagnose these patients earlier rather than later.”