The first successful clinical heart transplant was done by Christian Bmnard at Cape Town in South Africa in 1967. The inilial enthusiasm did no1 last long as methods of iinlnuno suppression were not available. Research at Stanford University led to two significant advances - drugs for immuno suppression and percutaneous endo myocardial biopsy for diagnosis of early rejection. In 1982,
Inteinalional Society of Heart and Lung Transplantation (ISHLT) was formed and it keeps an intenlational registry. Data for more than 62,000 heart transplantations done all over the world is available. Cui~ently nearly 4000 cardiac transplantation are done worldwide every y e a , most of thein in the U.S.
Indication
Patients in NYHA class IV with heart failure, refractory to medical management caused by end stage coronary artery disease or cardio myopathy will need heart transplant.
Patients who need frequent admission to hospitals and require continuous inotropic support should also undergo heart lransplantntion. Some patients may be in cardiogenic shock or low cardiac output requiting mechanical ventilation,intra aortic balloon pump,ventricular assist device or total artificial heart. If these patients' other systems are not irreversibly damaged, they are candidates for transplantation. A lesser percentage of palients with irreversible heart failure due to congenital anomalies, valvular heart disease or re,jection after one cardiac transplantation should undergo this operation. Patients whose cii.culalion is being supported by IABP, ventricular assist device or total artificial heart as bridge to transplantation are urgent candidates for transplantation.
Technique of Transplantation
After donor and recipient have been identified and screened, matched and decision finalized, there are two essential steps for operation:
1 ) Procurement of Donor Heart
These days multiple organ donation is the rule and preparations are made for harvesting kidneys, liver etc., along with the heart. Median sternotomy is done and pericardium is opened, aorta, SVC, IVC etc., are dissected beyond peiicardial reflection. Aorta is clamped and one litre of cold cardioplegic solution administered to the aortic root. Superior and inferior vena cavae are divided. The right and left pulmonary veins are divided at the pericardial reflection. Aorta is divided just proximal to the innoninate artely and right and left pulmonary arteries are divided and heart is removed and immersed in cold isotonic solution. The cardiac chambers are inigated with cold isotonic solution to remove all the debiis. The organ is placed in triple sterile plastic bags and transported in special ice chests even to far off places.
2) Recipient Operation
Recipient is put on cardio pulmonary by pass synchronizing with the arrival and preparation of donor heart. High ascending aortic and individual cannulation of SVC and IVC are done.
There are two techniques of cardiac transplantation:
a) Classic Technique
In this method, portions of left and light atria of both recipient and donor are retained. There is more atrial tissue of recipient, which might cause arrhythmias and tricuspid regurgitation. The operation starts with anastomosis of left atria of donor and recipient. The atrial septae and then the right atria are anastoinosed.
b) Bi-caval Anastomosis Teclznique
This is the cu~rently preferred technique. In prepsuing the donor heart, more of SVC is dissected and retained. The length of IVC retained depends on whether donor liver is used for transplant or not. Left atrium is divided behind the inter atrial groove and just in front of right and left pulmona~y veins. Aorta and pulmonary arteries are divided and recipient's heart removed. First the two left atria are anastomosed with 3 '0' prolene sutures and ends up anterior to right superior pulmonary vein. In this technique, there is no need for anastomosing atrial septum. Then end-to-end anastomosis of inferior and superior vena cavae are done with prolene sutures. After tailoring pulmonary arterial trunk,anastomosis is done with 4'0' prolene sutures. Finally the aortic anastolnosis is done. De-airing of the cardiac chambers and aortic root are done and aortic clamp removed. Atrial and ventricular pacing wires are placed.
Results
International Society for Heart and Lung Transplantation (ISHLT) maintains data from more than 300 centres starting from 1980. Data for 61,533 such operations are ,now available. After reaching a peak of 4,466 transplants in 1995, the numbers have been gradually declining. In the United States the number is fairly stable - around 2200 - more than the number from all the other countries put together.Survival at one year has remained constant - around 79 per cent. Risk of death ,is greatest in the first three months after operation. Thereafter there is a fall offrate of 4 per centlyear. Survival at five years is around 63 per cent falling to 43 per cent at 10 years and 23 per cent at 15 years. Stanford University in USA has the maximum experience. They have 150 patients surviving more than 10 years,38 patients more than 15 years and 8 patients more than 20 years. In their group longest survival is reported to be 23.5 years. Survival has improved after the introduction of cyclosporine A and OKT 3. However re-transplantation results are less satisfactoly - 49 per cent at one year and 15 per cent at 10 years.patients die of acute heart failure (early rejection) and infection. For late deaths,accelerated coronary artery disease and malignancy are partly responsible.
Inteinalional Society of Heart and Lung Transplantation (ISHLT) was formed and it keeps an intenlational registry. Data for more than 62,000 heart transplantations done all over the world is available. Cui~ently nearly 4000 cardiac transplantation are done worldwide every y e a , most of thein in the U.S.
Indication
Patients in NYHA class IV with heart failure, refractory to medical management caused by end stage coronary artery disease or cardio myopathy will need heart transplant.
Patients who need frequent admission to hospitals and require continuous inotropic support should also undergo heart lransplantntion. Some patients may be in cardiogenic shock or low cardiac output requiting mechanical ventilation,intra aortic balloon pump,ventricular assist device or total artificial heart. If these patients' other systems are not irreversibly damaged, they are candidates for transplantation. A lesser percentage of palients with irreversible heart failure due to congenital anomalies, valvular heart disease or re,jection after one cardiac transplantation should undergo this operation. Patients whose cii.culalion is being supported by IABP, ventricular assist device or total artificial heart as bridge to transplantation are urgent candidates for transplantation.
Technique of Transplantation
After donor and recipient have been identified and screened, matched and decision finalized, there are two essential steps for operation:
1 ) Procurement of Donor Heart
These days multiple organ donation is the rule and preparations are made for harvesting kidneys, liver etc., along with the heart. Median sternotomy is done and pericardium is opened, aorta, SVC, IVC etc., are dissected beyond peiicardial reflection. Aorta is clamped and one litre of cold cardioplegic solution administered to the aortic root. Superior and inferior vena cavae are divided. The right and left pulmonary veins are divided at the pericardial reflection. Aorta is divided just proximal to the innoninate artely and right and left pulmonary arteries are divided and heart is removed and immersed in cold isotonic solution. The cardiac chambers are inigated with cold isotonic solution to remove all the debiis. The organ is placed in triple sterile plastic bags and transported in special ice chests even to far off places.
2) Recipient Operation
Recipient is put on cardio pulmonary by pass synchronizing with the arrival and preparation of donor heart. High ascending aortic and individual cannulation of SVC and IVC are done.
There are two techniques of cardiac transplantation:
a) Classic Technique
In this method, portions of left and light atria of both recipient and donor are retained. There is more atrial tissue of recipient, which might cause arrhythmias and tricuspid regurgitation. The operation starts with anastomosis of left atria of donor and recipient. The atrial septae and then the right atria are anastoinosed.
b) Bi-caval Anastomosis Teclznique
This is the cu~rently preferred technique. In prepsuing the donor heart, more of SVC is dissected and retained. The length of IVC retained depends on whether donor liver is used for transplant or not. Left atrium is divided behind the inter atrial groove and just in front of right and left pulmona~y veins. Aorta and pulmonary arteries are divided and recipient's heart removed. First the two left atria are anastomosed with 3 '0' prolene sutures and ends up anterior to right superior pulmonary vein. In this technique, there is no need for anastomosing atrial septum. Then end-to-end anastomosis of inferior and superior vena cavae are done with prolene sutures. After tailoring pulmonary arterial trunk,anastomosis is done with 4'0' prolene sutures. Finally the aortic anastolnosis is done. De-airing of the cardiac chambers and aortic root are done and aortic clamp removed. Atrial and ventricular pacing wires are placed.
Results
International Society for Heart and Lung Transplantation (ISHLT) maintains data from more than 300 centres starting from 1980. Data for 61,533 such operations are ,now available. After reaching a peak of 4,466 transplants in 1995, the numbers have been gradually declining. In the United States the number is fairly stable - around 2200 - more than the number from all the other countries put together.Survival at one year has remained constant - around 79 per cent. Risk of death ,is greatest in the first three months after operation. Thereafter there is a fall offrate of 4 per centlyear. Survival at five years is around 63 per cent falling to 43 per cent at 10 years and 23 per cent at 15 years. Stanford University in USA has the maximum experience. They have 150 patients surviving more than 10 years,38 patients more than 15 years and 8 patients more than 20 years. In their group longest survival is reported to be 23.5 years. Survival has improved after the introduction of cyclosporine A and OKT 3. However re-transplantation results are less satisfactoly - 49 per cent at one year and 15 per cent at 10 years.patients die of acute heart failure (early rejection) and infection. For late deaths,accelerated coronary artery disease and malignancy are partly responsible.
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