- Email: [email protected]
Successful long-term outcome with prolonged ischaemic time allografts
Asia Pacific
J Thorac
Cardiovasc
Surg 1994;3(1)
Cardiothoracic
global ischaemia at 37°C. This was followed by blood cardioplegic induction at 37°C (CI-37:n=lO), 25°C (CI-25:n=lO) and 10°C (CI-lO:n=lO), respectively. Subsequently, cold-blood cardioplegia was done on each group 3 times, every 20 min at 10°C. Five hearts of each group were reperfused for 30 min with Krebs-Henseleite bicarbonate buffer at 37°C. The inosine leakage at cardioplegic induction was least in the CI-25 group (CI-25:0.64 f O.lSymol vs. CI10:1.05 k 0.27pmol and CI-37:1.46 + 0.24pmo1, p < 0.05). After 30 min of reperfusion, the CI-25 group showed good ATP recovery (CI-2584.1 + 16.2% vs. CI10:55.7 + 13.2% and CI-37:54.0 2 16.4%, p < 0.05). However the CI-10 group presented the smallest myocardial water content compared to CI-25 and CI-37 (CI-10:82.4 + 0.5% vs. CI-25:83.6 + 0.7% and CI-37:84.9 f 1.5%, p < 0.05 to CI-37). We conclude that in the group of CI-25, inosine leakage was minimised and myocardial ATP and CP recovered better than in the other 2 groups. In this condition, CI-25 was better than CI-37 and CI-10 in myocardial metabolic protection.
The indication for implantation was documented sustained ventricular tachycardia or aborted sudden cardiac death, not directly associated with acute cardiac ischaemia, and not controlled with anti-arrhythmic medication. Seven patients had cardiomyopathy; 28 had ischaemic heart disease. In 10 patients, ICD implantation was associated with concomitant ventricular aneurysm and/or coronary artery surgery. ,A further 6 patients had previously undergone coronary artery bypass grafting. Ten of the 35 patients have had their defibrillating patches placed at stemotomy, 21 at thoracotomy and four transvenously (2 patients also required a subcutaneous patch). Since 1984 there has been a gradual evolution both in the ICD devices and in the method of their lead placement. Initially all patients had epicardial pace-sense leads and pericardial or epicardial defibrillator patches. Subsequently the pace-sense leads have been placed endocardially. Now there is a move toward a totally transvenous lead implantation system. The device itself has become lighter and smaller, and evolved to having pacing, cardioverting and defibrillating functions. These have been consistently placed between the left rectus muscle and the posterior rectus sheath. Long-term follow-up has been 100% (1 month to 5 years). There have been no perioperative deaths and minimal morbidity, with 1 patient returning to the operating theatre for control of bleeding. There have been 3 late deaths (one from arrhythmia; two from heart failure); 1 patient underwent cardiac transplantation. Two units needed replacement due to power failure. One set of endocardial leads needed replacement following dislodgement. Our experience with the devices has been satisfactory.
Successful Long-term Outcome With Prolonged Ischaemic Tie Allografts G. Matalanis, E. Briganti, P. Bergin, D. Esmore Heart and Lung Replacement Service, Alfred Hospital Melbourne, Victoria, Australia The limited availability of cardiac allografts, together with increasing numbers of patients on the waiting list, restricts the population servicing in heart transplantation. An increase in the available donor pool has been facilitated by the utilisation of allografts with periods of ischaemia greater than 240 minutes. Consideration of the effect of allograft ischaemic time on recipient outome is particularly relevant to the Australian experience, given the size of the country and the location of the transplant units on the Eastern coast, necessitating long retrieval times if donor utilisation and population servicing are to be maximised. Of 150 cardiac transplants performed between February 1989 and March 1993, 44 (29%) were with allografts periods of ischaemia greater than 240 minutes. Basic recipient and donor demographics were similar in the 2 groups. Long-term cardiac allograft function is not compromised by prolonged ischaemic time, according to our data. Current data suggests that transcontinental cardiac allograft retrieval can be performed safely without long-term risk to cardiac transplant recipients and with an associated improvement in population servicing.
Implantuhle Cardioverter-defrihrillator Melbourne Hospital
abstracts
Early Experience With The Jyros Prosthetic Valve C. Munsch, J. McLenachan Leeds General Infirmary, Leeds, U.K. The innovative design of the Jyros valve combines the benefits of a wholely pyrolytic carbon with asymmetric rotating leaflets. This design reduces the potential for stagnation and thrombosis at the hinge mechanism. In vitro testing at IBEES Sheffield has demonstrated excellent haemodynamic and wear characteristics. The valve has been available clinically in the U.K. for 2 years and has been implanted by 6 surgeons in 5 centres. There have been 156 patients implanted, with a follow-up of 46,729 patient months. There have been 4 non-valve related hospital deaths and 2 incidences of endocarditis. There has been 1 non-valve related late death. There have been no reported thromboembolic episodes and no haemolysis. Ten mitral implants in our centre have been recently reviewed with doppler echocardiography. Calculated mean valve area for the 28 mm prosthesis was 3.30 cm2 (range, 1.75 to 4.92), comparing favourably with existing bileaflet valves. Rotation of the leaflets has been detected by radiological screening. Although we have relatively little follow-up data, early results for this new valve are encouraging.
Usage At Royal
T. McKenzie, J. Tatoulis Department of Cardio-Thoracic Surgery, Royal Melbourne Hospital, Melbourne, Victoria, Australia Between 1984 and May 1993, 37 implantable cardioverter-defibrillators (ICD) have been implanted in 35 patients. The patient population consisted of 29 males and 6 females with an average age of 58.5 years at implantation.
46
J Thorac
Cardiovasc
Surg 1994;3(1)
Cardiothoracic
global ischaemia at 37°C. This was followed by blood cardioplegic induction at 37°C (CI-37:n=lO), 25°C (CI-25:n=lO) and 10°C (CI-lO:n=lO), respectively. Subsequently, cold-blood cardioplegia was done on each group 3 times, every 20 min at 10°C. Five hearts of each group were reperfused for 30 min with Krebs-Henseleite bicarbonate buffer at 37°C. The inosine leakage at cardioplegic induction was least in the CI-25 group (CI-25:0.64 f O.lSymol vs. CI10:1.05 k 0.27pmol and CI-37:1.46 + 0.24pmo1, p < 0.05). After 30 min of reperfusion, the CI-25 group showed good ATP recovery (CI-2584.1 + 16.2% vs. CI10:55.7 + 13.2% and CI-37:54.0 2 16.4%, p < 0.05). However the CI-10 group presented the smallest myocardial water content compared to CI-25 and CI-37 (CI-10:82.4 + 0.5% vs. CI-25:83.6 + 0.7% and CI-37:84.9 f 1.5%, p < 0.05 to CI-37). We conclude that in the group of CI-25, inosine leakage was minimised and myocardial ATP and CP recovered better than in the other 2 groups. In this condition, CI-25 was better than CI-37 and CI-10 in myocardial metabolic protection.
The indication for implantation was documented sustained ventricular tachycardia or aborted sudden cardiac death, not directly associated with acute cardiac ischaemia, and not controlled with anti-arrhythmic medication. Seven patients had cardiomyopathy; 28 had ischaemic heart disease. In 10 patients, ICD implantation was associated with concomitant ventricular aneurysm and/or coronary artery surgery. ,A further 6 patients had previously undergone coronary artery bypass grafting. Ten of the 35 patients have had their defibrillating patches placed at stemotomy, 21 at thoracotomy and four transvenously (2 patients also required a subcutaneous patch). Since 1984 there has been a gradual evolution both in the ICD devices and in the method of their lead placement. Initially all patients had epicardial pace-sense leads and pericardial or epicardial defibrillator patches. Subsequently the pace-sense leads have been placed endocardially. Now there is a move toward a totally transvenous lead implantation system. The device itself has become lighter and smaller, and evolved to having pacing, cardioverting and defibrillating functions. These have been consistently placed between the left rectus muscle and the posterior rectus sheath. Long-term follow-up has been 100% (1 month to 5 years). There have been no perioperative deaths and minimal morbidity, with 1 patient returning to the operating theatre for control of bleeding. There have been 3 late deaths (one from arrhythmia; two from heart failure); 1 patient underwent cardiac transplantation. Two units needed replacement due to power failure. One set of endocardial leads needed replacement following dislodgement. Our experience with the devices has been satisfactory.
Successful Long-term Outcome With Prolonged Ischaemic Tie Allografts G. Matalanis, E. Briganti, P. Bergin, D. Esmore Heart and Lung Replacement Service, Alfred Hospital Melbourne, Victoria, Australia The limited availability of cardiac allografts, together with increasing numbers of patients on the waiting list, restricts the population servicing in heart transplantation. An increase in the available donor pool has been facilitated by the utilisation of allografts with periods of ischaemia greater than 240 minutes. Consideration of the effect of allograft ischaemic time on recipient outome is particularly relevant to the Australian experience, given the size of the country and the location of the transplant units on the Eastern coast, necessitating long retrieval times if donor utilisation and population servicing are to be maximised. Of 150 cardiac transplants performed between February 1989 and March 1993, 44 (29%) were with allografts periods of ischaemia greater than 240 minutes. Basic recipient and donor demographics were similar in the 2 groups. Long-term cardiac allograft function is not compromised by prolonged ischaemic time, according to our data. Current data suggests that transcontinental cardiac allograft retrieval can be performed safely without long-term risk to cardiac transplant recipients and with an associated improvement in population servicing.
Implantuhle Cardioverter-defrihrillator Melbourne Hospital
abstracts
Early Experience With The Jyros Prosthetic Valve C. Munsch, J. McLenachan Leeds General Infirmary, Leeds, U.K. The innovative design of the Jyros valve combines the benefits of a wholely pyrolytic carbon with asymmetric rotating leaflets. This design reduces the potential for stagnation and thrombosis at the hinge mechanism. In vitro testing at IBEES Sheffield has demonstrated excellent haemodynamic and wear characteristics. The valve has been available clinically in the U.K. for 2 years and has been implanted by 6 surgeons in 5 centres. There have been 156 patients implanted, with a follow-up of 46,729 patient months. There have been 4 non-valve related hospital deaths and 2 incidences of endocarditis. There has been 1 non-valve related late death. There have been no reported thromboembolic episodes and no haemolysis. Ten mitral implants in our centre have been recently reviewed with doppler echocardiography. Calculated mean valve area for the 28 mm prosthesis was 3.30 cm2 (range, 1.75 to 4.92), comparing favourably with existing bileaflet valves. Rotation of the leaflets has been detected by radiological screening. Although we have relatively little follow-up data, early results for this new valve are encouraging.
Usage At Royal
T. McKenzie, J. Tatoulis Department of Cardio-Thoracic Surgery, Royal Melbourne Hospital, Melbourne, Victoria, Australia Between 1984 and May 1993, 37 implantable cardioverter-defibrillators (ICD) have been implanted in 35 patients. The patient population consisted of 29 males and 6 females with an average age of 58.5 years at implantation.
46