eCardioVascular Beat

The surprising truth about aortic stenosis

Todd Caulfield, M.D., F.A.C.C., F.S.C.A.I.

Medical director, Interventional Cardiovascular Research
Medical director, Providence Valve Center

Aortic stenosis is a challenging disease frequently encountered in clinical practice. Patients often are diagnosed with asymptomatic severe aortic stenosis, but are they really? There is an understandable aversion to a surgical repair even as technology has advanced. Yet some old paradigms remain as true today as they were 50 years ago.

We all remember this chart, which shows survival after the onset of symptoms to be 50 percent after two years, and a meager 20 percent at five years.

Recent data for cohort B of the PARTNER trial (percutaneous valve {TAVI} vs. standard therapy in inoperable patients) confirmed this poor prognosis even in the setting of modern medical therapy.

This includes the aggressive use of balloon aortic valvuloplasty, which we perform regularly at Providence Heart and Vascular Institute to address symptoms in inoperable patients.

Despite this widespread knowledge, multiple studies have shown that patients with severe and symptomatic aortic stenosis often are not referred for consideration of therapy.

Charlson et al showed that the survival rate for patients 80 or older following aortic surgery was similar to that of a younger cohort, easing the concerns about greater surgical risk in an older population.

The study also showed that older patients were much less likely to be referred to surgery, even after adjusting for comorbidities and functional status.

Dispelling the myths

So why are patients not referred? For a variety of reasons: 

• Patients and physicians overestimate the surgical risk. One study from the University of Michigan found that the real operative risk of all unoperated symptomatic aortic stenosis patients was only 3.8 percent – far lower than what the treating physicians had assumed. One-year mortality in this untreated group was 34 percent, leading the investigators to state: “Some patients with severe symptomatic AS may be inappropriately denied access to potentially lifesaving therapy.”
• Patients themselves downplay the significance of their symptoms: “I am an old man, of course I am short of breath!”
• There’s a failure to recognize a subclinical but significant decline in functional capacity.

Simple suggestions:

• Beware of age discrimination – appropriate older patients do great with aortic valve surgery.
• Consider administering the Duke Activity Status Index (download) to your patients. This can be given even to patients with aortic stenosis at the time of check-in, like an ROS questionnaire. This will help to identify patients with a significant decline in functional capacity, and can be compared from visit to visit. You could save a life.
• Remember that severe aortic stenosis with reduced ejection fraction is a class I indication for aortic valve replacement.
• Refer patients with aortic stenosis to Providence Valve Center. This multidisciplinary program allows patients to be seen in consultation with a cardiologist and cardiothoracic surgeon to discuss the best treatment options. Other specialists will be consulted as needed, with guidance from the referring clinician. Teleconferencing with the referring clinician also will be available. Further testing will be obtained as necessary, and, as much as possible, at the time of the consultation for patient convenience.

Treatment for aortic stenosis is changing rapidly. New mechanical valves that may not require anticoagulation are being studied here at Providence Heart and Vascular Institute, as are other prosthetic valves.

Minimally invasive and robotic techniques also have improved dramatically over the past several years. Percutaneous therapies, from palliation with balloon aortic valvuloplasty to “curative” treatment with aortic valve replacement, will need to be considered.

It is in the patient’s interest to have all informed caregivers participate in a comprehensive discussion of treatment options for aortic stenosis. Providence Valve Center is available to respond to this need.