“In the PARTNER 3 clinical trial for low-risk patients, Transcatheter Aortic Valve Implantation (TAVI) significantly improved the rate of all-cause death, disability-causing stroke, and rehospitalization at one year, compared to surgical aortic valve replacement (SAVR). This showed that the convenient TAVI procedure was still beneficial to low-risk patients.”

Professor Park Seung-jung (left) and Professor Park Duk-woo at Asan Medical Center’s Cardiology Department take questions about Transcatheter Aortic Valve Implantation (TAVI) at a seminar in Seoul, Thursday.

So said Professor Park Duk-woo of the Department of Cardiology at Asan Medical Center at a seminar on Thursday, hosted by Edwards Lifesciences Korea to celebrate the 10th anniversary of the market release of Edwards Sapien, a heart valve, in the nation.

According to Park, the PARTNER 3 study compared the TAVI group with the SAVR group to assess the all-cause death, disability-causing stroke, or rehospitalization at one year. The results showed that only 8.5 percent of the TAVI group experienced a major cardiovascular event in one year, compared to 15.1 percent of the SAVR group.

Park explained that the most common cause of aortic stenosis was aging. In general, the disease is more likely to occur with old age, and it develops among people aged between 75 and 85 commonly, he said.

“The risk of patients increases when the three symptoms appear. They are difficulty in breathing, chest pain, and fainting. Existing studies have shown that the two-year survival rate is 50 percent on average,” Park said.

If any of the three symptoms appear, a drug administration is ineffective and the patient needs to replace the heart valve. There are two treatments available. One is SAVR where the surgeon opens the chest and changes the valve, and the other is TAVI where the surgeon inserts a catheter to an artery to replace the existing valve with an artificial one.

“SAVR is a major operation that requires not only opening the chest but also stopping the heart for a while to remove the calcified area,” Park said. “Young people can endure this well but it can be risky for the elderly. The TAVI procedure solved this problem.”

First introduced to Korea in 2010, TAVI procedures at local hospitals have grown gradually. Over the past decade, more than 40 centers have performed over 3,000 TAV procedures, according to Park.

Professor Park Seung-jung at AMC’s Cardiology Department said low-risk patients with a longer life expectancy would have no problem in artificial valve durability, and that it was possible to replace it one more time.

By 2025, almost all patients with a symptom of aortic stenosis will undergo TAVI, he predicted.

He also described the TAVI procedure in detail by listing TAVI cases for tricuspid and bicuspid aortic stenosis where he used Edwards Sapien.

“Before the procedure, we measure the aortic annular parameters by CT scanning. When selecting the valve size, we pick about 0-15 percent wider valve, depending on the degree of calcification. The more severe the calcification, the smaller we choose,” he said. “Edwards Sapien allows us to adjust the size, which is an advantage.”

For a better quality of life for patients, it would be best to choose a tissue valve over a mechanical valve, Park noted. In the past, those aged 65 or less choose a mechanical valve no matter what, but people did not consider the quality of life then, he said.

“If you replace your valve with a mechanical one, you have to be careful about bleeding and take a blood thinner. TAVI is a better choice because it does not require a blood thinner,” he said.

Asked whether TAVI has any problem, Professor Park Duk-woo said even patients aged 96 or 97 could be discharged three or four days after the procedure.

“The TAVI procedure can end within an hour without general anesthesia. Even if a patient has an underlying disease, there is no great concern,” he explained.

However, the national health insurance does not fully cover the TAVI procedure due to “political reasons,” he said. The Ministry of Health and Welfare, the Health Insurance Review and Assessment Service, and the National Health Insurance Service have discussed the issue for several years but failed to produce a meaningful result, he added.

The TAVI procedure is covered partially with the insurance benefit. The government supports 20 percent of the cost, and the patient, the rest 80 percent. According to Park, a patient needs to pay about 32 million won ($27,000) to undergo TAVI.

kch@docdocdoc.co.kr

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