乌鸦传媒

SAN FRANCISCO -- An initial strategy of aortic valve replacement for severe but asymptomatic stenoses yielded better long-term outcomes than a conservative approach, according to a Japanese registry.

Initial valve replacement was associated with a cumulative 15.4% incidence of all-cause mortality over 5 years compared with 26.4% for so-called watchful waiting (P=0.009), Tomohiko Taniguchi, MD, of Japan's Kyoto University, reported here at the Transcatheter Cardiovascular Therapeutics (TCT) meeting. The findings were published simultaneously in the Journal of the American College of Cardiology.

Upfront valve replacement also was associated with a lower likelihood of heart failure hospitalization (3.8% versus 19.9%, P<0.001).

Both associations remained significant in multivariable and in propensity-score matched analyses.

And, "in the present study, 41% of patients managed conservatively required aortic valve replacement within a median follow-up of 2 years, suggesting that one does not gain much by waiting," the researchers wrote in the journal.

"Often times we are taught in medical school that patients with severe asymptomatic aortic stenosis can just simply be followed,", conference co-director said at a TCT press conference where the findings were presented.

The guidelines support aortic valve replacement as reasonable for certain groups of higher-risk asymptomatic patients, noted , director of interventional cardiology at Beth Israel Deaconess Medical Center in Boston.

The question is those patients who are in the "intermediate zone," he said. "I think this is fabulous because it's raising the question for us now of whether we should intervene sooner with TAVR [transcatheter aortic valve replacement]."

The reason for having a high bar for asymptomatic patients was the upfront hit in periprocedural events with surgery, but "maybe we don't have to put the bar so high," agreed Kirtane, of New York-Presbyterian Hospital/Columbia University Medical Center in New York City.

The CURRENT AS registry included 3,815 consecutive patients with severe aortic stenosis (defined by a peak aortic jet velocity over 4.0 m/s, mean aortic pressure gradient over 40 mm Hg, or aortic valve area less than 1.0 cm²) at 27 centers in Japan. Among them, 1,808 were asymptomatic initially.

Most asymptomatic patients were conservatively managed (1,517 of the 1,808). Upfront valve replacement for the rest was surgical aortic valve replacement in all but one case.

"The extent of benefits appeared to be similar regardless of the current indications for aortic valve replacement, such as left ventricular dysfunction or very severe aortic stenosis," the researchers noted.

They acknowledged that ascertaining symptom status can be a challenge, because often patients "may not complain [of] any symptoms because of their sedentary lifestyle."

Kirtane agreed, noting that often patients say they have no symptoms but if you ask "Can you walk two blocks?" they will say "no."

Another challenge is that patients aren't always compliant with the watchful part of watchful waiting, the researchers added.

"Indeed in the current study, severe heart failure was the initial symptom in a sizable proportion of patients in the conservative group, in whom aortic valve replacement was less frequently performed than in patients without severe heart failure," they wrote, "and mortality was extremely high if aortic valve replacement was not performed."

The researchers noted the possibility of ascertainment bias.

of Mount Sinai School of Medicine in New York City and also a co-director of the TCT conference, cautioned that registries are flawed for many reasons and pointed to the lack of detail on peak gradients and other aspects that the guidelines cite in the decision for treatment.

"When we see large numbers of patients developing symptoms over time, you kind of think 'Did they get the right patients into the conservative management group?'," she commented at the press conference. "We need to tease [out] and strengthen our ways to evaluate aortic stenosis. I think that's what this registry is teaching us."

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