The operation is a daring operation: To replace a heart valve, cardiologists place a replacement through the groin of the patient and bring it to the heart and maneuver it into the place of the old valve.
Transcatheter aortic valve replacement (TAVR) procedure was mainly reserved for patients who are so old and ill that they can not survive open heart surgery. Now, two large clinical studies show that TAVR is equally useful in younger, healthier patients.
It could be even better, as it offers a lower risk of strokes and death compared to open heart surgery. Cardiologists say it would likely change the standard of care for most patients with failed aortic valves.
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Dr. Lederman was not involved in the studies and does not consult the two equipment companies that sponsored them.
In open heart surgery, a patient's ribs are torn apart and the heart is stopped to insert the new aortic valve.
In TAVR, the only incision is a small hole in the groin into which the catheter is inserted. Most patients are sedated, but are awake through the procedure, and recovery only takes days, not months, as is often the case after a standard surgery.
The results "shift our thinking from the question of who should get TAVR, why would anyone need surgery?" Howard Herrmann, Director of Interventional Cardiology at the University of Pennsylvania.
"If I was a patient, I would choose TAVR," Dr. Gilbert Tang, a cardiac surgeon at the Icahn School of Medicine at Mount Sinai, New York, who was not involved in the new research.
The studies will be published in the New England Journal of Medicine and presented on Sunday at the annual meeting of the American College of Cardiology.
The Food and Drug Administration is expected to approve the procedure for lower-risk patients. Up to 20,000 patients per year could qualify for TAVR, in addition to the nearly 60,000 middle and high risk patients who are now undergoing surgery.
"This is a clear win for TAVR," Dr. Michael J Mack, a cardiac surgeon at Baylor Scott and White's The Heart Hospital Plano in Texas. "We will be very selective," said Dr. Mack, who is a senior investigator in one of the studies.
Some healthier patients will still need the traditional surgery – for example, the one who has to undergo surgery Born with two valves on the aortic valve instead of the usual three. Two valves can lead to premature failure of the aortic valve.
TAVR has not been tested in these patients, and the disease is more common in younger patients with low surgical risks.
Aortic valve failure results from a stiffening of the valve that controls the flow of the large vessel in the heart that supplies blood to the rest of the body. Patients are often tired and short of breath.
There is no way to prevent the condition and there is no other treatment than to replace the valve. The main risk factor is the increasing age.
Although more than 1,000 patients were recorded in both studies, the studies differed slightly in design, making direct comparisons difficult.
The study, by Dr. med. Mack and Dr. Martin Leon, an interventional cardiologist at Columbia University, New York, recorded deaths, disability, and hospitalization a year after the intervention. The rate was 15 percent at surgery versus 8.5 percent at TAVR.
The incidence of death and disability – the most important factor for patients – was 2.9 percent for surgery versus 1 percent for TAVR.
The second study estimated deaths or disabilities at two years and a rate of 6.7 percent for surgery versus 5.3 percent for TAVR.
The studies were sponsored by manufacturers of TAVR valves, Edwards Lifesciences of Irvine, California, and Medtronic, based in Dublin. The two companies produce slightly different valves.
The Edwards valve is compressed onto a balloon catheter which is pushed by a blood vessel from the groin into the aorta. As soon as he reaches the aorta, a cardiologist inflates the balloon and expands the valve, pushing the defective valve aside.
The Medtronic valve is made of Nitinol, a metal that shrinks when cold and expands when warm. The valve is cooled and placed on a catheter. When he reaches the aorta, the cardiologist pulls back a scabbard and releases the new valve. Warmed up by the body, it expands to fill the narrowed opening, and stays there.
In the conventional operation, a doctor cuts out the old valve and sews a new one by removing the old valve instead of leaving it in the chamber's heart.
Dr. Jeffrey J. Popma, an interventional cardiologist at Beth Israel Deaconess in Boston, led the second study and is an advisor to both manufacturers. He uses both devices in surgery and said the important finding is that both are preferable to surgery.
Leading surgeons and cardiologists took part in the studies at academic medical centers, many of which were consulted as advisors. Independent data and safety monitoring committees oversaw the studies, and independent statisticians confirmed the findings.
Aortic valves have been replaced for decades, and surgeons know that the valves used during surgery last at least 10 to 15 years. It remains to be seen whether TAVR valves will prove themselves.
The question is particularly important for younger patients. The mean age of the subjects was in the lower to middle 70 years of age in the current studies and was one decade or more younger than most patients who were now receiving TAVR.
Hospitals offering TAVR will be affected if lower-risk patients decide to do so. Said Herrmann. The TAVR valves cost far more than surgically placed valves, but insurers generally pay for both procedures equally.
More than half a dozen companies produce surgical valves, but only two TAVR valves. Dr. Herrmann said the prices for TAVR valves are likely to fall.
At the moment, it is up to most patients to decide what procedure to use, Dr. Popma – TAVR or surgery.
For Robert Pettinato 79-year-old retiree in Scranton, Pennsylvania, there was no question. He had some chest pain and it was hard to play a round of golf.
However, when his cardiologist Mr. Pettinato said last year that he needed a new valve, he could only get TAVR to participate in a clinical trial. He enrolled in the Edwards study at the University of Pennsylvania.
He had TAVR in November, stayed in the hospital for 24 hours and went home. A few days later, he went to the football game at Lehigh University against its arch rival Lafayette. (He's a Lehigh alumnus and never misses this game.)
Shortly thereafter, his younger brother Jim, who lives in Florida, had to get an aortic valve replacement. He wanted TAVR, but the clinical trials were completed. Instead, he had to undergo surgery.
It took four months for his brother to recover enough to play a round of golf, Pettinato said .
Pettinato is golf again. "I'm the luckiest guy in the world," he said.