Early Result of Heart Transplantation in Japan: Osaka University Experience

Japanese strategies to maximize heart and lung availabilities: experience from 100 consecutive brain-dead donors

OBJECTIVE

Because the donor shortage is extremely severe in Japan because of a strict organ transplantation law, special strategies have been established to maximize heart and lung transplantations (HTs and LTs, respectively). We reviewed 100 consecutive brain-dead donors to evaluate our strategies to identify and manage heart and lung donors.

METHODS

We retrospectively reviewed all 100 consecutive brain-dead donors procured since the law was issued in 1997. There were 56 mens and the overall mean donor age was 43.5 years. The causes of death were cerebrovascular disease (n = 62), head trauma (n = 20), and asphyxia (n = 16): Since November 2002, special transplant management doctors were sent to donor hospitals to assess cardiac and lung functions, seeking to identify transplant opportunities. They stabilized donor hemodynamics and lung function by administering antidiuretic hormone intravenously and performing bronchofibroscopy for pulmonary toilet.

RESULTS

Seventy-nine HTs, 1 heart-lung transplantations, and 78 LTs (46 single and 32 bilateral) were performed. By applying these strategies organs per donor were increased from 4.5 to 6.8. Among heart donors, 61/80 were marginal: high inotrope requirement (n = 29), cardiopulmonary resuscitation (n = 28), and/or >55 years old (n = 20). None of the 80 HT recipients died of primary graft failure (PGF). Patient survival rate at 10 years after HT was 95.4%. Among lung donors, 48/65 were marginal: pneumonia (n = 41), chest trauma (n = 4), and >55 years old (n = 9). Only 2/78 LT recipients died of PGF. Patient survival rate at 3 years after LT was 72.2%. After inducing frequent pulmonary toilet, lung procurement and patient survival rates increased significantly after LT.

CONCLUSIONS

Although the number of cases was still small, the availability of organs has been greater and the outcomes of HT/LT acceptable.

Prediction of outcome in patients with liver dysfunction after left ventricular assist device implantation

Although postoperative liver dysfunction (LD) following left ventricular assist device (LVAD) implantation is associated with high mortality, outcome is difficult to predict in patients with liver dysfunction. We aimed to clarify factors affecting recovery from LD after VAD implantation. A total of 167 patients underwent LVAD implantation, of whom 101 developed early postoperative LD, defined as maximum total bilirubin (max T-bil) greater than 5.0 mg/dl within 2 weeks. We set two different end-points, unremitting LD, and 90-day mortality. The rates of early mortality (90 days) and recovery from LD were 36 % (36/101) and 72 % (73/101), respectively. Univariate analysis showed that preoperative body weight, preoperative mechanical support, preoperative T-bil and creatinine, left ventricular diastolic dimension, right VAD (RVAD) insertion, cardiopulmonary bypass time, postoperative cardiac index, and postoperative T-bil and central venous pressure (CVP) on postoperative day (POD) 3 (non-recovered vs recovered, 12.4 ± 4.5 vs 9.5 ± 3.6 mmHg) were higher in patients with unremitting LD. Preoperative T-bil, RVAD insertion, and T-bil and CVP on POD 3 (non-survivor vs survivor, 12.4 ± 4.4 vs 9.4 ± 3.6 mmHg) were also higher in non-survivors. Multivariate analysis demonstrated that CVP on POD 3 was predictive of recovery from postoperative LD (OR 0.730, P < 0.05) and 90-day mortality (OR 0.730, P < 0.05). A key outcome factor in patients who developed early postoperative LD after LVAD implantation was postoperative liver congestion with high CVP. To overcome postoperative LD, appropriate management of postoperative CVP level is important.

Risk factor analysis of long-term support with left ventricular assist system

BACKGROUND

This study was designed to elucidate the key factors for successful long-term support with a left ventricular assist system (LVAS) in the situation where heart transplantation is rarely available.

METHODS AND RESULTS

From 1992 to 2008, 106 patients underwent 121 LVAS implantations at Osaka University Hospital (Toyobo: 77; Novacor: 18; HeartMate: 14; Jarvik2000: 8; EvaHeart: 2; DuraHeart: 2). Risk factors for infection were early on the former implanted period (odds ratio (OR) 3.30), Toyobo (OR 2.25), mechanical right heart support (OR 2.30) and cardiopulmonary bypass time (OR 1.01). Left atrium as the inflow site was the risk factor for cerebrovascular events (OR 2.84). Older age (OR 1.04) and mechanical right heart support (OR 4.70) were risk factors for mortality. Risk factors for requiring mechanical right heart support were preoperative extracorporeal membranous oxygenation support (OR 5.641), serum total bilirubin (OR 1.11) and serum creatinine (OR 2.46). On the basis of the risk analysis for mortality, patients were divided into 2 subgroups (low and high risk) and the respective cumulative survival at 1 year after LVAS implantation was 75.2% and 25.0%.

CONCLUSIONS

Appropriate selection of device, patient and the timing of implantation and less invasive operation are important for successful long-term LVAS support.

Role of ventricular assist devices in the German heart allocation system

The Eurotransplant (ET) allocation algorithm, newly implemented in 2000, gives priority for heart transplantation (HTx) to patients with high urgency (HU) status, but now this status is rescinded upon ventricular assist device (VAD) implantation and only regained if severe complications occur during mechanical circulatory support (MCS). We studied the effects of this change on the patients in our institute who were waiting for HTx with MCS. The median duration of MCS until HTx in adult patients gradually increased from 3.1 months in 1994, reaching a peak of 16.7 months in 2000, and then gradually decreased to 6.0 months in 2003. Among the patients with VAD implantation as a bridge to HTx, two patients were on MCS for more than 1 year (the longest duration of MCS being 1.6 years) at the end of 1999, and this figure increased to nine patients and a maximum MCS duration of 3.7 years at the end of 2003. These data imply that the patients in whom a complication occurred in the early phase of MCS and who had overcome this complication underwent HTx early with HU status, and those who were stable during MCS waited a long time for HTx. Furthermore, the number of patients in the latter group is increasing. The new allocation algorithm imposes on patients with MCS waiting for HTx who are relatively young and free from complications and serious coexisting disease, very long-term MCS without an end to VAD bridging, which is almost equivalent to destination therapy.

Successful bridge to resynchronization therapy with a left ventricular assist system in a patient with idiopathic dilated cardiomyopathy

Implantation of a left ventricular assist system (LVAS) in patients with idiopathic dilated cardiomyopathy (DCM) may improve cardiac function and allow explantation of the device. Generally, an ejection fraction of more than 40% is considered necessary for successful weaning from an LVAS, but less than 10% of DCM patients with an LVAS can achieve such a significant recovery of cardiac function. Cardiac resynchronization therapy, or atrial-synchronized biventricular pacing, has been found to treat congestive heart failure and ventricular dyssynchrony effectively. Here we report on a patient with an LVAS, in whom enough functional recovery could be obtained with resynchronization therapy for the device to be explanted successfully. A 32-year-old man was implanted with a Toyobo-NCVC paracorporeal LVAS to treat his intractable heart failure caused by idiopathic dilated cardiomyopathy. While on the LVAS for 8 months, his cardiac function recovered to some extent. The ejection fraction of his left ventricle (LVEF) improved from 9% to 41%. He chose explantation of the device rather than heart transplantation. Because he occasionally showed a wide QRS pattern on his ECG, epicardial biventricular pacing leads as well as a biventricular pacemaker were implanted on LVAS explantation surgery. An echocardiogram 2 weeks after explantation showed a marked difference in his LVEF by switching his biventricular pacing on and off (40% with biventricular pacing on and 29% with it off). Biventricular pacing may help recovery of cardiac function in selected LVAS patients and contribute to the increase in bridge to recovery cases.