Valvular Interventions for the Asymptomatic and Low Risk: Coming Soon to a Cath Lab Near You?

PARIS, France—Interventional cardiologists have a “tremendous responsibility” to operate on completely asymptomatic patients with valvular disease, according to Patrick Serruys MD, PhD (Erasmus Medical Center, Rotterdam, the Netherlands), who dedicated his EuroPCR 2016 keynote lecture to the topic of early percutaneous intervention in this patient group.

 “Surgery has moved step-by-step from symptomatic and high-risk patients to intermediate and low-risk patients, and has addressed more and more asymptomatic patients with functional abnormalities. [But] they don’t dare to approach the asymptomatic patients with anatomical abnormalities,” he said.

Interventionalists must offer options that are less invasive, multistage, and repetitive, Serruys continued. “We are working on the beating heart. We see what we do simultaneously. So I believe that we have the chance to move step by step to the intermediate and low-risk,” he said.

Beyond Watchful Waiting for Aortic Stenosis

Lower risk can mean many things in the field of aortic stenosis. With regard to age, Serruys pointed out that “elderly patients with multiple comorbidities pose a costly burden on the healthcare system.” Because of that, cost-effectiveness for this population can only be achieved by earlier intervention and not by conservative management. “But the gained QALYs are limited, and durability is not an issue given the very low long-term survival,” he said.

On the other hand, “younger patients with a low burden of comorbidities gain more QALYs if they receive valve replacement or repair, but they are exposed to incremental risk of structural valve deterioration-derived events,” Serruys observed.

Current guidelines recommend watchful waiting until symptoms emerge. However, he called for a randomized clinical trial to determine if they should change. Besides the hard clinical endpoints of mortality and stroke, researchers might consider the overall risk/benefit ratio to be an alternative endpoint as it would not require as large of a sample size, Serruys suggested. Cost-effectiveness could also be a future target, he said, but not until the “device price becomes more affordable and not inflated by the consideration of return on investment.”

Risk stratification will be incredibly important going forward, he stressed, adding that observing valve calcification with multidetector computed tomography and observing aortic stenosis by jet velocity are options for doing this. Traditionally, surgeons have been “confronted with the ethical dilemma of exposing an asymptomatic patient to a significant risk of 30 day mortality of about 1.7%,” he said. “This ethical dilemma will be passed to the cardiologists if a less traumatic therapy can be offered provided that periprocedural safety can be guaranteed.”

All About That Mitral

With regard to the mitral valve, “transcatheter technology is exploding,” according to Serruys. “Asymptomatic mitral regurgitation is not benign,” he said, but the question remains of whether it is justified to treat asymptomatic patients.

Conservative management is not without a price, Serruys observed, noting a 2009 study that showed a survival rate of only 50% at 5 years with a conservative approach. “Only patients with minimal symptoms have the privilege of restoring normal life expectancy after surgical mitral valve replacement,” he added. “Patients with reduced ejection fraction have excess mortality even after replacement. Patients with increased left ventricular end systolic diameter have excessive [risk] even after surgery.”

Also, mitral valve surgery is safe and effective enough today to justify early intervention, Serruys commented—something that has not yet been established for the majority of transcatheter mitral valve innovations currently in development.

Looking forward, he expects the landscape of valvular interventions will change drastically. Serruys reflected back on his keynote talk on aortic valves in 2007—when only 667 patients had been treated with the pioneering therapy worldwide. “See where we are now,” he concluded.

Future of Interventional Is Specialization  

In a panel discussion that followed Serruys’ talk, Ulrich Gerckens, MD (St. Petrus Hospital, Bonn, Germany) said the concept of “low risk” needs to be better defined in terms of both scoring and age. “What we still see in Germany [are] less risky patients [in terms of] scoring, but still the age of treated TAVI patients is about 80 years,” he commented.

Panel co-moderator Jean Fajadet, MD (Clinique Pasteur, Toulouse, France), agreed. “Surgeons today accept that . . . all octogenarian patients, even [those at] low risk, are treated by TAVI. This now is accepted. The problem of the risk in elderly patients I think today is solved,” he said. “The key question today for the future will be can we reduce the threshold of 80 years old to 75, 70, and 65.”

Jacques Monsegu, MD (Groupe Hospitalier Mutualiste de Grenoble, France), said the most important topic now is valve durability, especially given the results of a study presented earlier this week at EuroPCR 2016 that showed as many as 50% of first-generation TAVR valves are demonstrating signs of degeneration within 8 to 10 years. “We are waiting for long-term durability data, but I think this is the future,” he said.

Summing up Serruys’ overall message, panel co-moderator Javier Escaned, MD, PhD (Hospital Clinico San Carlos, Madrid, Spain), liked the notion of interventionalists having a responsibility to treat low-risk patients. “This is something that we have to keep in mind at a time when procedures have been simplified and streamlined,” he said. “At the same time, we’ll have to do a more thorough screening of the patients and [risk stratify them] even when technically speaking the procedure can become simpler.”

As the community forges ahead, optimal teaching of the next generation of interventionalists must also be prioritized, according to Jonathan Hill, MD (King’s College Hospital, London, England). “In a way, we’re now faced with a challenge,” he said. “Should valvular training be a part of every interventional cardiologist’s fellowship training? Do we need to change our training programs? Because there’s going to be a huge demand for operators [and] procedures.”

Fajadet said this will be the key question. “For a fellow today, . . . I would say he will need to learn the coronary and he will need to learn the structural,” he suggested, adding that training needs to be longer than it was 25 years ago. “Today we have a standard baseline platform of learning and teaching, including the coronary field and the structural. After that there will be some specialization I’m sure of that,” he predicted.

At his high-volume institution, there is a group spending approximately 90% of their time doing coronary cases and another group doing primarily peripheral and structural cases, Fajadet reported. While things might look different at lower-volume centers, he said, the future of interventional cardiology is specialization.

 Source: 
Serruys PW. Early percutaneous intervention for valvular disease…. An opportunity for improving patient’s outcome. Presented at: EuroPCR 2016. May 18, 2016. Paris, France.

Related Stories:

• SAPIEN 3 Superior to Surgery Among Intermediate-Risk Patients in Observational Trial
• As Technique Inches Forward, Outcomes Improve for Transcatheter Treatment of Severe Calcific Mitral Disease
• Early Results for Transcatheter Mitral Valve Replacement Reveal Complications and Challenges for the Long Road Ahead