Midterm survival rates high with medical management in registry
Asymptomatic aortic stenosis (AS) patients followed by experienced heart valve clinics had good midterm survival in a registry study, although certain factors correlated with poorer prognosis.
Survival rates with medical management were 93% at 2 years, 86% at 4 years, and 75% at 8 years, according to the pooled institutional databases of 10 heart valve clinics in Europe, Canada, and the U.S.
Survival without aortic valve replacement (AVR) among patients who entered the registry with severe AS was 54% at 2 years and 32% at 4 years.
For those who did get transcatheter or surgical AVR, the procedure was associated with a “very low” 0.9% rate of 30-day mortality, according to Patrizio Lancellotti, MD, PhD, of University of Liège Hospital in Belgium, and colleagues reporting online in JAMA Cardiology.
Predictors of mortality in patients with severe AS included: a peak aortic jet velocity over 5 m/s, left ventricular ejection fraction (LVEF) less than 60%, older age, higher systolic blood pressure, and chronic obstructive pulmonary disease.
“These findings provide support for consideration of early elective AVR in these patients. Closer and more frequent (every 6 to 12 months) clinical and echocardiographic follow-up might be implemented in patients with moderate AS and a peak aortic jet velocity of 3.0 m/s or greater or LVEF less than 60%,” Lancellotti’s group suggested.
A small study from 2010 had shown that asymptomatic patients with very severe AS (peak aortic jet velocity 5.5 m/s or faster) had markedly higher event-free survival rates than did patients with jets between 5.0 and 5.5 m/s (P<0.0001).
The new findings lend further support to close surveillance of these patients and consideration of earlier intervention when values get close to the “very severe” range, Mario Gössl, MD, PhD, of Minneapolis Heart Institute, told MedPage Today. He was not a part of Lancellotti’s study.
The researchers analyzed the Heart Valve Clinic International Database records from 2001-2014, focusing on the 1,375 asymptomatic patients with aortic valves smaller than 1.5 cm2 and LVEF over 50% at entry. The study cohort comprised 60.7% men and had an average age of 71. Average follow-up time was 27 months.
Almost two-thirds of the group had severe AS as determined by routine transthoracic echocardiography. AVR was performed in 39.4% at a median of 8.7 months after study entry and was done surgically in most cases.
Sudden death occurred at a “low rate” of 0.65% over the study period, the researchers said.
Overall, they noted the outcomes of asymptomatic AS patients in this registry are better than the ones in previous studies, likely reflecting the combination of appropriate monitoring, planning, and high adherence to guidelines. “However, our data highlight the need for additional efforts with probably closer follow-up in these patients, since the occurrence of overt heart failure remains a significant problem even in heart valve centers of excellence.”
“If validated in other studies, these observations could influence decision making and the timing of surgical referral,” agreed Patrick O’Gara, MD, of Brigham and Women’s Hospital in Boston, and Robert Bonow, MD, of Chicago’s Northwestern Medicine, in an editor’s note accompanying the paper.
In that regard, the EARLY TAVR randomized trial is underway to compare early transcatheter AVR to active surveillance among asymptomatic patients with severe AS. There is still no trial for surgical AVR, noted Lancellotti and colleagues.
Limitations of their study included that 22% of eligible patients from their registry didn’t have enough information to make it into the analysis. Additionally, asymptomatic status was not confirmed with exercise testing in all cases.
“Symptoms are notoriously hard to assess, and the LVEF may remain preserved even with very significant myocardial dysfunction as demonstrated by longitudinal strain,” commented James Thomas, MD, also of Northwestern Medicine. “One deficiency in the paper is that they did not assess strain in these patients, which is proving to be a sensitive measure of myocardial dysfunction, particularly with preserved ejection fraction.”
Lancellotti, O’Gara, and Bonow disclosed no conflicts of interest.
Study co-authors reported several ties to industry.
Lancellotti P, et al “Outcomes of patients with asymptomatic aortic stenosis followed up in heart clinics” JAMA Cardiol 2018; DOI: 10.1001/jamacardio.2018.3152.
O’Gara PT, Bonow RO “Thresholds for valve replacement in asymptomatic patients with aortic stenosis” JAMA Cardiol 2018; DOI: 10.1001/jamacardio.2018.3277.
Read the original article on Medpage Today: Silent Aortic Stenosis Outcomes Good With Close Surveillance