Asymptomatic Severe Aortic Stenosis - JACC [PDF]

JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY

VOL. 66, NO. 25, 2015

ª 2015 BY THE AMERICAN COLLEGE OF CARDIOLOGY FOUNDATION

ISSN 0735-1097/$36.00

PUBLISHED BY ELSEVIER INC.

http://dx.doi.org/10.1016/j.jacc.2015.10.029

EDITORIAL COMMENT

Asymptomatic Severe Aortic Stenosis What Are We Waiting For?* Mackram F. Eleid, MD, Patricia A. Pellikka, MD

“Observe due measure, for right timing is in all things the most important factor.”

C

—Hesiod, Works and Days (c. 700 BC) (1) alcific degenerative aortic stenosis (AS) is a common cause of acquired valvular heart disease affecting predominantly older

adults. Over time, accumulation of valve calcifica-

tion restricts leaflet motion, leading to progressive outflow obstruction, afterload mismatch, and symptoms. Traditionally, the asymptomatic phase of severe AS (stage C) has been associated with a low risk of sudden death (2–4), such that close observation for the development of symptoms is recommended before proceeding with aortic valve replacement (AVR) (5).

watchful waiting for the development of symptoms, and beg the question, “What are we waiting for?” in the patient with asymptomatic severe AS. One of the unique strengths of the dataset presented by Taniguchi et al. (6) is the large number of patients with severe AS who were initially managed conservatively. Most contemporary cohorts have a higher referral rate for AVR, leaving small numbers of conservatively managed patients and limiting statistical comparisons. Additionally, the authors should be commended for including hospitalizations for heart failure as part of the primary endpoint, because the development of congestive heart failure in AS represents a more advanced stage of disease that should be avoided. Interestingly, AVR mortality was higher in patients who underwent intervention

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In this issue of the Journal, Taniguchi et al. (6) report 5-year outcomes of the CURRENT AS (Contemporary Outcomes after Surgery and Medical Treatment in Patients with Severe Aortic Stenosis) registry of 1,808 patients with asymptomatic severe AS who were initially treated either conservatively (n ¼ 1,517) or with initial AVR (n ¼ 291). The authors found a higher rate of mortality (26.4% vs. 15.4%; p ¼ 0.009) and hospitalizations for heart failure (19.9% vs. 3.8%; p < 0.001) at 5 years of follow-up in patients who were managed conservatively compared with those undergoing initial AVR. These data seemingly conflict with recommendations of

after symptom onset compared with asymptomatic patients, further supporting the notion that earlier surgery may be beneficial. During a median follow-up of 2 years, 41% of patients initially managed conservatively required AVR, which is in keeping with previous estimates that progression to required intervention within 5 years of developing severe AS is almost inevitable. Why might asymptomatic AS be a different problem now than was observed only 10 to 20 years ago? Several potential reasons for this may exist. The rate of sudden death in this study was slightly higher than previously reported (1.5% per year compared with earlier estimates of 1.0% per year) (2,3). Today, AS patients are an elderly population, often with multiple comorbidities, potentially leaving them more vulnerable to the hemodynamic derangements asso-

*Editorials published in the Journal of the American College of Cardiology

ciated with severe AS. Furthermore, AVR mortality is

reflect the views of the authors and do not necessarily represent the

lower now than it used to be and can be accurately

views of JACC or the American College of Cardiology. From the Division of Cardiovascular Diseases and Internal Medicine, Mayo Clinic College of Medicine, Rochester, Minnesota. Both authors have reported that they have no relationships relevant to the contents of this paper to disclose.

estimated using the Society for Thoracic Surgeons risk calculator (7). Although the study methods were robust (6), asymptomatic status was not confirmed by treadmill

JACC VOL. 66, NO. 25, 2015

Eleid and Pellikka

DECEMBER 29, 2015:2842–3

Asymptomatic Severe Aortic Stenosis

exercise

possibility

with severe AS (8), for instance, is not represented

of undetected or unrecognized symptoms in some

test,

therefore

leaving

the

in this Japanese cohort with mean body mass index

patients due to sedentary lifestyle. In fact, the

of 22 kg/m 2, which potentially could affect AVR

updated American College of Cardiology/American

outcomes.

Heart Association guidelines provide a class IIa

Appropriate timing of the intervention for each

recommendation for AVR in asymptomatic patients

individual patient is essential to balance the nat-

with severe AS (stage C1) who have decreased

ural risk of severe AS with the risk of AVR. This

exercise

(5).

study sheds new light on optimal management

Furthermore, as the authors point out, monitoring

strategies in asymptomatic severe AS and raises

for symptoms can be an imprecise undertaking

many more important questions. Ultimately, how-

and some patients will inevitably be lost to follow-

ever, we await a randomized controlled trial of

up using this strategy. Although a retrospective

patients with asymptomatic severe AS to address

study, the authors appropriately used a propensity

the question of whether early AVR is preferable to

score-matched cohort to minimize selection bias

a strategy in which AVR is deferred until symp-

in

toms develop.

tolerance

comparing

on

outcomes

treadmill

in

testing

patients

managed

conservatively versus with initial AVR. Despite these measures, the population in this Japanese-

REPRINT REQUESTS AND CORRESPONDENCE: Dr.

based study may have unique features compared

Patricia A. Pellikka, Division of Cardiovascular Diseases

with Western populations that limit the generaliz-

and Internal Medicine, Mayo Clinic College of Medicine,

ability of the study results. The high prevalence

200 First Street Southwest, Gonda 6-138, Rochester,

of obesity in the United States, even in patients

Minnesota 55905. E-mail: [email protected].

REFERENCES 1. Brainyquotes. Hesiod quotes. Available at: www. brainyquote.com/quotes/quotes/h/hesiod133841.

4. Rosenhek R, Binder T, Porenta G, et al. Predictors of outcome in severe, asymptom-

with asymptomatic severe aortic stenosis. J Am Coll Cardiol 2015;66:2827–38.

html. Accessed October 28, 2015.

atic aortic stenosis. N Engl J Med 2000;343: 611–7.

7. O’Brien SM, Shahian DM, Filardo G, et al. The

2. Otto CM, Burwash IG, Legget ME, et al. Prospective study of asymptomatic valvular aortic stenosis. Clinical, echocardiographic, and exercise predictors of outcome. Circulation 1997; 95:2262–70. 3. Pellikka PA, Sarano ME, Nishimura RA, et al. Outcome of 622 adults with asymptomatic, hemodynamically significant aortic stenosis during prolonged follow-up. Circulation 2005;111: 3290–5.

5. Nishimura RA, Otto CM, Bonow RO, et al. 2014 AHA/ACC guideline for the management of patients with valvular heart disease: a report of the American College of Cardiology/ American Heart Association Task Force on Practice Guidelines. J Am Coll Cardiol 2014;63: e57–185. 6. Taniguchi T, Morimoto T, Shiomi H, et al. Initial surgical versus conservative strategies in patients

Society of Thoracic Surgeons 2008 cardiac surgery risk models: part 2 – isolated valve surgery. Ann Thorac Surg 2009;88:S23–42. 8. Eleid MF, Sorajja P, Michelena HI, et al. Flowgradient patterns in severe aortic stenosis with preserved ejection fraction: clinical characteristics and predictors of survival. Circulation 2013;128:1781–9. KEY WORDS aortic stenosis, aortic valve replacement, valvular heart disease

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