Features January 2013 Issue

Patient’s Overall Health is Key to Aortic Valve Procedure Outcome

Undergoing a transcatheter aortic valve implant can be lifesaving, but patients who are too sick before surgery may not benefit.

The development of the transcatheter aortic valve implant (TAVI) has been a breakthrough in the treatment of inoperable patients with failing aortic valves. But a Cleveland Clinic study found that the survival prognosis for these patients depends largely on the severity of their comorbidities, those health complications unrelated to their valve disease.

NIH

Transcatheter transapical aortic valve implant. Left: Deployment of prosthetic aortic valve. Right: Both coronary arteries were clearly visible after aortic valve implant.

Murat Tuzcu, MD, an interventional cardiologist at Cleveland Clinic, and author of the PARTNER B study, found that TAVI provides patients significantly more benefits than standard medical therapy. “The benefits of [TAVI] were sustained for three years including all-cause mortality, cardiovascular mortality, repeat hospitalization, and functional status,” he says.

However, the PARTNER B trial also revealed that patients with major health problems in addition to their aortic valve disease are not likely to see those same outcomes. As a result, Dr. Tuzcu says that patient selection for this procedure must be done carefully and comprehensively, and that “aggressive management of illness after TAVI” is essential.

Anticoagulant medication therapy is an important component of post-surgery care, as is a cardiac rehab program that stresses the role of exercise, diet, medication adherence and other heart-healthy lifestyle adjustments these patients must make when living with a new valve.

How TAVI works
Because the aorta supplies blood throughout the body, when the aortic valve starts to fail, the result can have multiple impacts on a person’s overall health. Reduced blood flow to the major organs, for example, can be devastating. Valve replacement, rather than repair, is usually required when the aortic valve is severely damaged.

The aortic valve can be replaced with traditional open-heart surgery for some patients. But for those who are considered too frail or otherwise poor candidates for surgery, aortic valve replacement wasn’t an option for many years. But with the recent development of transcatheter aortic valve replacement (TAVR), those inoperable patients now have options. Doctors can deliver a new valve to the heart with a catheter through a blood vessel from any of several starting points—the thigh, forearm and the chest. Once the new valve is implanted, the catheter is removed and the patient starts to enjoy the benefits of vastly improved blood flow.

Valve options
In the PARTNER B trial, doctors tested the Edwards Lifesciences Sapien transcatheter aortic valve, which uses bovine tissue for the valve leaflets that are held in place with a stainless steel frame.

In open surgery, doctors often have the option of using a valve made of animal tissue, or a completely mechanical valve. A mechanical valve is designed to last for the patient’s lifetime. Biological valves tend to not last as long as mechanical valves, though new technological advances are extending the durability of these devices.

Evaluating complications
Unfortunately, many patients with aortic valve disease also have other major health problems. And Dr. Tuzcu notes that not all health symptoms disappear once a new valve is in place. “We have been developing a sense that there are types of patients, with COPD, for example, that don’t really improve their shortness of breath that much with the new valve. These people are not necessarily excluded, but we have to pay attention to them,” he says.

But on the upside, Dr. Tuzcu stresses that, in general, the options for patients with valve disease continue to expand.

“We should not promote one procedure, we should promote a program of taking care of high-risk valvular heart disease patients—this may be surgical treatment, percutaneous treatment, or optimization of the patient’s clinical status in the critical care unit, balloon valvuloplasty, or a wise solution to the patient’s concomitant problems,” he says. “We should not perceive what is accomplished with the PARTNER program only as a success with the procedure, but rather how the program can be established with multiple disciplines.”