A 60-year-old woman surnamed Tseng (曾) last month became the first patient in Asia to receive a successful heart transplant to treat dextrocardia situs inversus totalis, and only the sixth in the world to undergo such treatment.
Dextrocardia is a congenital defect in which the heart is located in the right side of the body, Tri-Service General Hospital Surgery Department director Tsai Chien-sung (蔡健松) said.
Dextrocardia situs inversus totalis is a condition in which all visceral organs are “mirrored,” or located on the opposite side of their normal location.
Tseng was discharged yesterday after a month’s hospitalization.
Tseng said that in her six decades, she has not been hospitalized very often and only knew that her heart was “slightly different” from other people’s.
Between the 22nd and 23rd day of embryonic development, the heart usually slants to the right, but then normally slants back to the left between the 32nd and 34th day, Tsai said. However, if the tip of the heart does not slant back to the left, it results in dextrocardia.
Depending on the location — whether the heart is merely slanting right or whether it is mirrored — dextrocardia can be divided into dextrocardia of embryonic arrest and dextrocardia situs inversus respectively, Tsai said.
Dextrocardia occurs in one in 10,000 births, and the chance of being born with dextrocardia situs inversus totalis is about one in 1 billion, Tsai said.
Tsai also said that dextrocardia is not believed to be passed down genetically.
However, if one family member has dextrocardia — or if one of the parents have the condition — the chances of being born with the condition is between 2 percent and 4 percent, roughly about the chance of developing congenital heart diseases, Tsai said.
Heart transplants for people with dextrocardia situs inversus totalis are very difficult because all the major blood vessels are also mirrored, Tsai said, adding that transplant surgeries requires the inversion of the transplanted organ — if it were from someone with a normal heart placement — in the chest cavity, then reconnecting all the major blood vessels.
Tsai said that he had to leave a longer length of blood vessels during the surgery considering that the blood vessels had a longer distance to connect, adding that when connecting the blood vessels, he had to take precautions to leave enough space for the main artery, the pulmonary artery and the superior vena cava.
All three had to be in the same space, Tsai said, adding that care had to be taken that the blood flow could adequately pass through the blood vessels.
There had been incidences of blood vessels becoming entangled, impeding blood flow into the heart and causing the surgery to fail, Tsai said.
The hospital took the matter very seriously and held many meetings over the surgery, Tsai said, adding that he had also been in constant contact with his mentor, Wei Cheng (魏崢), the head of Cheng Hsin General Hospital’s Department of Cardiology.
Tsai said documentation over the past two decades showed that there had only been five cases of heart transplants for patients with dextrocardia situs inversus totalis worldwide, with one in Belgium who had survived, and two cases in Asia — both of whom had died soon after the surgery.
“Tseng was the first successful case in Asia, as well as the sixth in the world with her condition to have received a heart transplant,” Tsai said.