Pediatric Heart Transplant Candidates With Failed Donor Heart Allocation After Eurotransplant Urgency Listing Profit From Pretransplant Mechanical Circulatory Support Bridging

Abstract:  Due to the Eurotransplant organ allocation policy, urgency listing for heart transplantation (HTx) remains in force until ventricular assist device (VAD) implantation in Germany. We studied the prognosis of HTx candidates after failed donor heart allocation in urgent status. We studied all adult and pediatric (<18 years) HTx candidates who underwent primary HTx after Eurotransplant urgency listing between January 2001 and December 2006 (Group A-uHTx [A-"u"rgent status "HTx"], n  = 99; Group P-uHTx [P-"u"rgent status "HTx"], n  = 24) and those to whom donor heart was not urgently allocated before VAD implantation or death in the same period (Group A-fHA [A-"f"ailed "H"eart "A"llocation], n  = 21, Group P-fHA [P-"f"ailed "H"eart "A"llocation], n  = 10). Mortality rate after urgency listing or primary VAD implantation was studied in each group. In adult patients, 1-year mortality rate after urgency listing in Group A-fHA was 56.8% and significantly higher than in Group A-uHTx (30.6%, P  < 0.001, log-rank test). After failed urgent heart allocation, 15 out of 21 patients in Group A-fHA had VAD implantation and two patients (9.5%) underwent HTx after VAD implantation. In pediatric patients, 1-year mortality rate in Group P-fHA was 40.0% and significantly higher than in Group P-uHTx (8.5%, P  < 0.05). In Group P-fHA, all 10 patients underwent VAD implantation after failed urgent heart allocation and six patients (60.0%, P  < 0.01 vs. Group A-fHA, Fisher's exact test) underwent HTx after VAD implantation. After failed urgent donor heart allocation, pediatric HTx candidates seem to profit more from mechanical circulatory support than adults.     

Destiny of candidates for heart transplantation in the Eurotransplant heart allocation system

OBJECTIVE: We analyzed the prognosis of candidates for heart transplantation (HTx) after being listed with 'urgent status' for donor heart allocation or after ventricular assist device (VAD) implantation without application for urgent status. METHODS: Urgent status as used in this study refers to both the high urgency (HU) status awarded by Eurotransplant until August 31, 2005 and the urgent (U) status that replaced it from then on. Patients who underwent primary VAD implantation between January 2001 and December 2006 and who were listed as transplantable (T) (group VAD-prim, n=159), and patients listed primarily in urgent status before VAD implantation and/or HTx during the same period (group U-prim, n=168) were enrolled in the study. Group U-prim consists of subgroups: group U-HTx (n=123), who underwent primarily HTx in urgent status; group U-VAD (n=25), who underwent primarily VAD implantation in urgent status; patients who died in urgent status before HTx or VAD implantation (n=6); and patients in urgent status without HTx or VAD implantation (n=14). The survival rate in each group was studied. RESULTS: Survival rates after VAD implantation in group VAD-prim were comparable to those after urgent status listing in group U-prim (67.0% vs 68.5% for 1-year survival, 56.6% vs 65.8% for 2-year survival, respectively). Actuarial survival after listing for urgent status in group U-HTx was significantly better than that in group U-VAD (73.7% vs 46.0% for 1-year survival, p<0.05, log-rank test). Actuarial survival during mechanical circulatory support after the VAD implantation (censored at HTx or weaning from the device) in group VAD-prim was significantly better than that in group U-VAD (80.7% vs 56.2% for 3-month survival, p<0.001, log-rank test). CONCLUSIONS: In order to receive urgent HTx, HTx candidates may choose urgency listing without primary VAD implantation at the risk of failed donor heart allocation in urgent status. However, the prognosis of the patients in the latter situation is poor.     

Pneumatic pulsatile ventricular assist devices in children under 1 year of age.

OBJECTIVE: Although considerable progress has been made on ventricular assist devices (VAD) for adults, pneumatic pulsatile circulatory support in young infants is still limited. There is a need for long-term ventricular assist devices to bridge the failing myocardium of young children until recovery or transplantation. Miniaturized devices and innovative modalities need to be optimized. We report on our experience. METHODS: From 1/1992 to 6/2004, 18 infants (6 male/12 female) under 1 year of age were treated with the Berlin Heart Excor VAD. The infants were divided into two groups, depending on the year of treatment. Group A consists of eight infants resuscitated and supported with a pulsatile pneumatic ventricular assist device between 1992 and 1998 and group B consists of 10 infants treated between 1999 and 6/2004. With the pediatric-sized Berlin Heart we used miniaturized extracorporeal pneumatically driven blood pumps, the lowest stroke volume being 10 ml. RESULTS: In 18 children, age 3-345 (median 147) days, artificial replacement of heart function was applied for long-term support (1-64, median 10 days) as a life-saving measure in our hospital. Nine had LVAD and nine BVAD support. All were in cardiogenic shock with multiorgan failure; three had fulminant myocarditis, four cardiomyopathy, and one chronic stage of congenital heart disease. Five children were weaned from the system, three reached heart transplantation, and 10 died on the VAD. There were no differences between groups A and B regarding age, body weight or diagnosis, but the duration of mechanical support differed: Group A, median 2, range 1-16 days; group B, median 12, range 1-100 days. Since 1999 (group B), the survival rate of our small infants has increased to 70% whereas none of the infants in group A survived to be discharged. CONCLUSIONS: The outcome of VAD support in small infants is no longer inferior to that of adult support, now optimized cannulas, modified anticoagulation and optimized surgical and intensive care management have been established.     

Outcomes of Patients Undergoing Combined Heart–Kidney Transplantation With or Without Prior Ventricular Assist Device

BackgroundBoth combined heart–kidney transplantation and ventricular assist devices (VADs) pose significant challenges, including sensitization, immunosuppressive treatment, and infrastructure demands. Despite these challenges, we hypothesized that the recipients of combined heart–kidney transplants with and without VADs would have equivalent survival. We aimed to compare the survival of heart–kidney transplant recipients with and without prior VAD placement.MethodsWe retrospectively analyzed all patients enrolled in the United Network for Organ Sharing database who underwent heart–kidney transplants. We created a matched cohort of patients undergoing heart–kidney transplantation with or without prior VAD using 1:1 nearest propensity-score matching with preoperative variables.ResultsIn the propensity-matched cohort, 399 patients underwent heart–kidney transplantation with prior VAD, and 399 underwent heart–kidney transplantation without prior VAD. The estimated survival of heart-–kidney recipients with prior VAD was 84.8% at one year, 81.2% at 3 years, and 75.3% at 5 years. The estimated survival of heart–kidney recipients without prior VAD was 86.8.7% at one year, 84.0% at 3 years, and 78.8% at 5 years. There was no statistically significant difference in the survival of heart–kidney transplant recipients with or without prior VAD at one year (P = .42; Figure 2), 3 years (P = .34), or 5 years (P = .30).ConclusionDespite the increased challenge of heart–kidney transplantation in recipients with prior VAD, we demonstrated that these patients have similar survival to those who underwent heart–kidney transplantation without previous VAD placement.     

Outcomes With Ventricular Assist Device Versus Extracorporeal Membrane Oxygenation as a Bridge to Pediatric Heart Transplantation

Extracorporeal membrane oxygenation (ECMO) has long been the sole means of mechanical support for pediatric patients with end‐stage cardiac failure, but has a high waitlist mortality and a reported survival to hospital discharge of less than 50%. The purpose of this study was to compare waitlist mortality and survival for ECMO versus ventricular assist device (VAD) support. A review was conducted of all patients listed for heart transplantation (HTx) since 2002 and requiring mechanical support. VAD support has been available from 2004 (Berlin Heart Excor Pediatrics). Competing risks analysis was used to model survival to one of four outcomes (HTx, death on waitlist, delisting, improvement). Thirty‐six patients were on mechanical support while awaiting HTx (21 ECMO, 12 VAD, three both). Median age at listing was 1.2 years (birth–16.6 years) for ECMO and 11.3 years (0.3–14.6 years) for VAD. Diagnosis was cardiomyopathy in 33% for ECMO and 93% for VAD. Median time to HTx was 37 days (1–930) overall, 20 days (1–85) for ECMO, and 39 days (5–108) for VAD. Mechanical support was associated with increased odds of HTx (hazard ratio [HR] 2.4 [1.7–3.3], P < 0.0001) but also delisting or death waiting (HR 3.0 [1.1–7.8], P = 0.03). Waitlist mortality of 38% on ECMO was reduced to 13% with VAD use. Survival post‐HTx to hospital discharge was better in the group on VAD support (92 vs. 80%). Pediatric patients requiring mechanical support as a bridge to HTx have short wait times but high waitlist mortality. Those patients who survived to be put on the Berlin Heart Excor Pediatric device based on individualized clinical decision making then had a lower waitlist mortality, a longer duration of support, and a higher survival to transplantation and hospital discharge.     

Mechanical heart support at the Deutsches Herzzentrum Berlin: Recent developments (2011)

Since the inception of the mechanical circulatory support (MCS) program at the Deutsches Herzzentrum Berlin (DHZB) in 1987, more than 1600 patients have received support with 18 different designs of technical blood pump systems, in accordance with the respective state of the art. At the beginning, pulsatile pneumatic extracorporeal ventricular assist devices (VAD) and implantable pneumatic total artificial hearts (TAH) were available, followed by pulsatile electromechanical implantable devices. At this time the assist program was based on three objectives: bridging to recovery, bridging to heart transplantation (HTx) and for permanent support. Very soon (in 1995) patients of advanced age – over 65 years – were included in the program. In 1998 rotary blood pumps with continuous flow entered the program, from 2006 edging out step by step the pulsatile systems. Today the implantable pulsatile systems have disappeared from the DHZB program, with the exception of the extracorporeal uni‐ or biventricular pneumatic EXCOR systems (Berlin Heart GmbH), which are the only systems available for newborns and children. The only approved total artificial heart is the CardioWest device, implanted in rare cases after explantation of the natural heart. Miniaturized rotary blood pumps, axial flow turbines or centrifugal radial flow pumps are leading today's market. The size and configuration of one of these pumps, the hydrodynamically and magnetically levitated HeartWare HVAD, allowed its application as a biventricular implantable assist device. The worldwide first clinical implantation of this system was performed at the DHZB in 2009. With the increasing number of patients needing immediate circulatory support and the stagnating or even decreasing number of donor hearts available for HTx, the extreme discrepancy means that other therapies are gaining increasing importance. The objectives of the MCS program therefore had to focus on permanent VADs, thus creating a growing population of long‐term outpatients with implanted systems, living with their families a near‐normal life. Within a quarter century VAD implantation has grown from an experimental procedure into an established and generally accepted therapy. Facing the rapidly increasing population of patients with end‐stage heart failure and the stagnating number of heart transplants, the use of VAD technology may represent the most advanced progress in cardiac care in the coming years. Further minaturization of the devices will allow the treatment of patients with a wide age spectrum, from newborn children to the elderly, even with biventricular support. The ultimate goal will be the development of a durable total artificial heart, based on the rotary blood pump technology, with transcutaneous energy transfer through the intact skin, guaranteeing the patients optimal quality of life for many years of support.     

Pneumatic pulsatile ventricular assist device as a bridge to heart transplantation in pediatric patients

Despite the remarkable advances with the use of ventricular assist devices (VAD) in adults, pneumatic pulsatile support in children is still limited. We report on our experience in the pediatric population. A retrospective review of 17 consecutive children offered mechanical support with Berlin Heart as a bridge to heart transplant from February 2002 to April 2010 was conducted. The median patient age was 3.9 years (75 days to 13.3 years). The median patient weight was 14.1 kg (2.9–43 kg). Before VAD implantation, all children were managed by multiple intravenous inotropes and mechanical ventilation (14) or extracorporeal membrane oxygenation (3). All patients had right ventricular dysfunction. Nine patients required biventricular mechanical support (BVAD), but in all other cases a single left ventricular assist device proved sufficient (47%). The median duration of VAD support was 47 days (1–168 days). The median pre‐VAD pulmonary vascular resistance index (Rpi) was 5.7 WU/m² (3.5 to 14.4 WU/m²). Eleven patients (65%) were successfully bridged to heart transplantation after a median duration of mechanical support of 68 days (6–168 days). Six deaths occurred (35%), three for neurological complications, one for sepsis, and two others for device malfunctioning. Since 2007, the survival rate of our patients has increased from 43% to 80%, and the need for BVAD has decreased from 86% to 30%. In two patients with Rpi >10 WU/m², unresponsive to pulmonary vasodilatator therapy, Rpi dropped to 2.2 and 2 WU/m² after 40 and 23 days of BVAD support, respectively. Seven patients (41%) required at least one pump change. Of 11 patients undergoing heart transplant, four developed an extremely elevated (>60%) panel reactive antibody by enzyme‐linked immunosorbent assay, confirmed by Luminex. All of them experienced at least one acute episode of rejection in the first month after heart transplant, needing plasmapheresis. The survival rate after heart transplantation was 100% with a median follow‐up of 25.4 months (6 days to 7.7 years). Mechanical support in children with end‐stage heart failure is an effective strategy as a bridge to heart transplantation with a reasonable morbidity and mortality. BVAD support may offer an additional means to reverse extremely elevated pulmonary vascular resistance.     

Single-center experience of pediatric heart transplantation in taiwan

Heart transplantation (HTx) is a treatment for end-stage heart failure or a complex or inoperable congenital defect. The long-term survival and the adequate donor to recipient body weight (D/R BW) ratio remain to be determined. From March 1995 to May 2004, 14 children (6 months-16 years of age) underwent HTx due to underlying diseases of idiopathic dilated cardiomyopathy (n = 10; 71.4%), congenital heart disease (n = 3; 21.4%), and Kawasaki disease (n = 1; 7.1%). Donor-recipient body weight ratio ranged from 0.89 to 3.9. Big heart syndrome was present in one patient when D/R BW ratio was more than 3. Actuarial survival was 92.9% at 5 years after transplantation. Only the one patient who had Kawasaki disease died due to early primary graft failure. HTx is a feasible method with good long-term survival rates for end-stage heart failure or for complex or inoperable congenital defects. After careful pretransplant evaluation, a high D/R BW ratio (more than 3) is acceptable.     

Ventricular assist devices as a bridge to heart transplantation or as destination therapy in pediatric patients

Purpose

Despite the remarkable advances with the use of ventricular assist devices (VAD) in adults, pneumatic pulsatile support in children is still limited. We report on our experience in the pediatric population.

Methods

Retrospective review of 27 consecutive children offered mechanical support with Berlin Heart as a bridge to heart transplant, and Jarvik 2000 as a destination therapy from February 2002 to October 2011.

Results

The median patient age was 4.8 years (range = 75 days to 20.5 years). The median patient weight was 18.6 kg (range = 2.9-63 kg). We divided the patients in two groups, including in group I patients assisted for bridging to heart transplantation and in group II patients with Duchenne's dystrophy assisted as destination therapy. In the group I, 11 patients required biventricular mechanical support (BVAD), but in all other cases, a single left VAD proved sufficient (56%). The median duration of VAD support was 48 days (1 to 192 days). The median pre-VAD pulmonary vascular resistance index (Rpi) was 5.7 WU/m² (3.5 to 14.4 WU/m²). Twelve patients (48%) were successfully bridged to heart transplantation after a median duration of mechanical support of 63 days (range = 2-168 days). Ten deaths occurred (40%), three for neurological complications, two for sepsis, two for multiorgan failure, and three other for device malfunctioning. Since 2007, the survival rate of our patients has increased from 33% to 75%, and the need for BVAD has decreased from 89% to 23%. In the group II, two patients with mean age of 15.3 years were assisted with Jarvik 2000, and both of them are alive in a follow-up of 10.4 months. In two patients with Rpi > 10 WU/m², unresponsive to pulmonary vasodilatator therapy, Rpi dropped to 2.2 and 2 WU/m² after 40 and 23 days of BVAD support, respectively. Six patients (32%) required at least one pump change. Of 12 patients undergoing heart transplantation, five developed an extremely elevated (>60%) panel-reactive antibody by enzyme-linked immunosorbent assay, confirmed by Luminex. All of them experienced at least one acute episode of rejection in the first month after heart transplant, needing plasmapheresis. The survival rate after heart transplantation was 100% with a median follow-up of 34.4 months (45 days to 8.7 years).

Conclusions

Mechanical support in children with end-stage heart failure is an effective strategy as a bridge to heart transplantation with a reasonable morbidity and mortality. BVAD support may offer an additional means to reverse extremely elevated pulmonary vascular resistance. The total implantable system opens a future scenarios for patients not eligible for heart transplantation.     

Pulsatile mechanical cardiac assistance in pediatric patients with the Berlin heart ventricular assist device

Mechanical cardiac assistance for neonates, infants, children and adolescents may be accomplished with pulsatile ventricular assist devices (VAD) instead of extracorporeal membrane oxygenation or centrifugal pumps. The Berlin Heart VAD consists of extracorporeal, pneumatically driven blood pumps for pulsatile univentricular or biventricular assistance for patients of all age groups. The blood pumps are heparin-coated. The stationary driving unit (IKUS) has the required enhanced compressor performance for pediatric pump sizes. The Berlin Heart VAD was used in a total number of 424 patients from 1987 to November 2001 at our institution. In 45 pediatric patients aged 2 days-17 years the Berlin Heart VAD was applied for long-term support (1-111 days, mean 20 days). There were three patient groups: Group I: "Bridge to transplantation" with various forms of cardiomyopathy (N = 21) or chronic stages of congenital heart disease (N = 9); Group II: "Rescue" in intractable heart failure after corrective surgery for congenital disease (N = 7) or in early graft failure after heart transplantation (N = 1); and Group III: "Acute myocarditis" (N = 7) as either bridge to transplantation or bridge to recovery. Seventeen patients were transplanted after support periods of between 4 and 111 days with 12 long-term survivors, having now survived for up to 10 years. Five patients (Groups I and III) were weaned from the system with four long-term survivors. In Group II only one patient survived after successful transplantation. Prolonged circulatory support with the Berlin Heart VAD is an effective method for bridging until cardiac recovery or transplantation in the pediatric age group. Extubation, mobilization, and enteral nutrition are possible. For long-term use, the Berlin Heart VAD offers advantages over centrifugal pumps and ECMO in respect to patient mobility and safety.     

Extracoporeal Membrane Oxygenation Hybrid With Thoratec Ventricular-Assist Devices as Double Bridge to Heart Transplantation

Ventricular-assist devices (VADs) have benefitted patients with end-stage heart failure as a bridge to heart transplantation (HTx). Herein, we describe our experience with HTx in the presence of extracorporeal membrane oxygenation (ECMO) together with the Thoratec VAD (Thoratec Corp, Pleasanton, California). From May 1996 to June 2009, mechanical circulatory support with the Thoratec VAD was provided in 20 patients. Before implantation of the VAD, circulation in 17 patients was maintained using ECMO. Although 350 patients underwent HTx during that period, only 13 patients (65%) received suitable donor organs for orthotopic HTx. The 20 patients ranged in age from 10 to 80 years; 3 were female, and 17 were male; and 17 (85%) required ECMO before VAD implantation. In 11 of 17 patients (65%), the VAD was implanted as a double bridge to HTx. The demand for mechanical circulatory support in patients with acute hemodynamic collapse has led to major improvements in clinically available systems such as ECMO as a double bridge to VAD implantation. We use ECMO as a rescue procedure in patients with acute hemodynamic deterioration. However, during ECMO support, left ventricular afterload increases. If prolonged support is necessary, a VAD may be required. We observed that 65% of patients who received support from an ECMO hybridized with the Thoratec VAD could wait for a suitable donor for HTx. We recommend use of ECMO for short-term support (<1 week) and the Thoratec VAD for medium- or long-term support as a bridge to HTx.     

Die Rolle von B-Zellen und Makrophagen bei der Entwicklung mikrovaskulärer Veränderungen nach Herztransplantation

Background

Graft vessel disease is one of the main limiting factors to long-term survival after heart transplantation (HTx). A number of risk factors for the development of epicardial vasculopathy have been identified, but accelerating factors for the development of small vessel disease remain uncertain. This study tests the role of B cells and macrophages in microvascular disease after heart transplantation.

Material and Methods

The study population consisted of 422 patients (72 females, 350 males, mean age at HTx 46 years) who underwent heart transplantation because of terminal heart failure (274 = dilated cardiomyopathy, 115 coronary artery disease, 33 = others). Out of a total of 809 paraffin-embedded endomyocardial biopsies without evidence of acute cellular rejection according to the classification of the International Society for Heart and Lung Transplantation 393 without evidence of the Quilty phenomenon were investigated 0–10 years after heart transplantation. This selection was made to exclude transient vascular reaction as response to acute rejection and to exclude elevated B cell reactivity due to B cells in Quilty lesions. In H&E stainings vascular reaction (endothelial cell swelling and vessel wall thickening) was graded and immunohistochemistry was performed for T cells (clone UCHL1), B cells (clone L26) and macrophages (clone KP1) and evaluated semi-quantitatively (light microscopy x 200). According to time of harvest EMBs were divided into 5 time intervals after HTx (1st–4th month, N = 70; 5th–12th month, N = 48; > 1st–2nd year, N = 71; > 2nd– 4th year, N = 78; > 4th–10th year, N = 126). All data were analyzed using non-parametric tests.

Results

During the first postoperative year, 72% of EMBs were positive for T cells, 5.7% positive for B cells and 100% positive for macrophages. Endothelial cell swelling and vessel wall thickening early after HTx were present in one half of the EMBs. Positive reaction for T cells and macrophages and evidence of endothelial cell swelling decreased with time after heart transplantation. Positive reaction for B cells was less frequent and increased slightly during the observation time, while vessel wall thickening dominated the last observation interval (< 4th–10th year). Severity of vascular reaction was independent of immunohistochemical evidence of B cells and macrophages, but correlated positively with evidence of T cells (p < 0.05).

Conclusions

While activation of the humoral and the unspecific immunologic system is common after heart transplantation, microvascular alterations seem to develop independently of these findings.     

Mechanical circulatory support in severe heart failure: single-center experience

Ventricular assist devices (VADs) have become important therapeutic tools to treat patients with end-stage cardiac failure. VADs are an essential component of transplantation programs as they successfully bridge individuals who would otherwise die. Recently left ventricular VAD (LVAD) therapy has been proposed as alternative to heart transplantation (HTx) for patients who are not transplant candidates. Other indications have now expanded into areas such as postcardiotomy failure, acute myocarditis, and acute massive myocardial infarction. From 1988 to May 2003, 80 patients received left or biventricular mechanical circulatory support including 78 as a bridge to and two as an alternative to HT. All patients survived the operation. Mean duration of VAD support was 77 +/- 150 days. Fifty-one points (63.8%) underwent heart transplantation; 3 (3.8%) recovered and were weaned from VADs. Major bleeding episodes occurred in 11 patients (13.8%) and major neurologic events occurred in 8 (10%). Sixteen patients (20%) were discharged home while waiting for HTx. Twenty-two patients (27.5%) died on VAD. In conclusion, VAD therapy proved effective in bridging patients with end-stage heart failure to HTx. While on LVAD support patients who were assisted with implantable wearable devices could be discharged at home, improving their quality of life.     

Outcomes of Heart Transplantation for Cardiac Amyloidosis: Subanalysis of the Spanish Registry for Heart Transplantation

Amyloidosis (Am), a systemic disease, has poor prognosis because of organ damage produced by protein deposition in the extracellular space. Although heart transplantation (HTx) is possible, donor availability concerns and high mortality make this approach controversial. The Spanish Registry for Heart Transplantation includes 25 Am patients (54 ± 9 years): 13 with AL type, 2 with AA and 10 with TTR mutation. Fifteen patients (60%) died during follow-up (4.9 ± 1.3 years): 9 AL-Am patients, both AA-Am patients and 4 with TTR-Am. HTx survival for Am patients was similar to patients without Am at 1 month but significantly worse at 5 years: 46% versus 78% (p < 0.02). Of 10 AL-Am patients undergoing successful HTx, 4 died of systemic Am. Stem cell transplantation was performed in 3 (1 died of acute rejection). Five of 10 patients with TTR-Am underwent liver transplant; 4 remained alive at the last follow-up. Findings include poor outcome for AL-Am patients despite HTx and better survival for TTR-Am patients if HTx is associated with liver transplantation. Given the shortage of donors and poor outcome for Am patients, we would recommend that HTx be reserved for patients without or with mild systemic Am and be supplemented by additional therapies as indicated.     

Experience with over 1000 implanted ventricular assist devices

PURPOSE: The use of ventricular assist devices (VADs) in patients with chronic end-stage or acute heart failure has led to improved survival. We present our experience since 1987. SUBJECTS AND METHODS: Between July 1987 and December 2006, 1026 VADs were implanted in 970 patients. Most of them were men (81.9%). The indications were: cardiomyopathy (n = 708), postcardiotomy heart failure (n = 173), acute myocardial infarction (n = 36), acute graft failure (n = 45), a VAD problem (n = 6), and others (n = 2). Mean age was 46.1 (range 3 days to 78) years. In 50.5% of the patients the VAD implanted was left ventricular, in 47.9% biventricular, and in 1.5% right ventricular. There were 14 different types of VAD. A total artificial heart was implanted in 14 patients. RESULTS: Survival analysis showed higher early mortality (p < 0.05) in the postcardiotomy group (50.9%) than in patients with preoperative profound cardiogenic shock (31.1%) and patients with preoperative end-stage heart failure without severe shock (28.9%). A total of 270 patients were successfully bridged to heart transplantation (HTx). There were no significant differences in long-term survival after HTx among patients with and without previous VAD. In 76 patients the device could be explanted after myocardial recovery. In 72 patients the aim of implantation was permanent support. During the study period 114 patients were discharged home. Currently, 54 patients are on a device. CONCLUSIONS: VAD implantation may lead to recovery from secondary organ failure. Patients should be considered for VAD implantation before profound, possibly irreversible, cardiogenic shock occurs. In patients with postcardiotomy heart failure, a more efficient algorithm should be developed to improve survival. With increased experience, more VAD patients can participate in out-patient programs.     

Current Status of Heart Assist and Replacement in Taiwan

Abstract: The first clinical application of intraaortic balloon pumps (IABP) in Taiwan was in 1976 to treat post-cardiotomy cardiogenic shock. It is now the most commonly used circulatory assist. From 1991 to 1995, 186 patients received IABP support with an overall mortality rate of 41.9%. The male patients had the best survival rate, 67%, after coronary artery bypass grafting. The first extracorporeal membrane oxygenation (ECMO) was in 1987 to treat intractable heart failure caused by severe acute rejection after heart transplantation. Because of poor outcome, patients only received ECMO sporadically during the past years. From November 1994 to November 1995, 30 patients received ECMO support with 50% of them eventually weaned from ECMO and 27% discharged. For short-term support or emergency rescue, ECMO was a good choice. When long-term support was required, the ventricular assist device (VAD) was a more suitable assist. One patient who received Thermedics VAD developed right heart failure and finally died of sepsis and multiple organ failure. VAD should be implanted before the secondary organ failure. The first successful clinical heart transplantation in Taiwan was performed on July 17, 1987. From 1991 to 1995, 102 patients underwent heart transplantation. The operative mortality was 3.9%, and the 1 and 5 year actuarial survival rates were 86 ± 3% and 77 ± 5%, respectively. To improve the success rate of clinical heart transplantation, organ donation should be encouraged.     

Ventricular assist device application as a bridge to pediatric heart transplantation: a single center's experience

Objectives

There are limited options for mechanical circulatory support to treat end-stage heart failure in pediatric patients. Although extracorporeal membrane oxygenation is commonly used in infants and children, ventricular assist devices (VAD) provide a longer duration of support with fewer complications before recovery or as a bridge to heart transplantation (HTx), as described herein.

Methods

This retrospective chart review of eight patients transplanted from April 2008 to December 2011, after left ventricular assist device (LVAD) implantation due to end-stage heart failure. Their mean age was 12 years (9-15 y) and mean body weight, 48 kg (20-78). All were New York Heart Association functional class IV with mean left ventricular ejection fractions less than 15%.

Results

The six patients (75%) received HTx after a mean LVAD support duration of 43.2 days; 2 (25%) died before a suitable heart became available. Their mean duration of LVAD support was 30 days. There were 4 (50%) who experienced clinically evident thromboembolic events: 3 (37.5%) cerebrovascular with 1 mortality and 1 (12.5%) as acute limb ischemia. Transient hemodialysis was performed in 4 (50%). Bloodstream infection identified in 6 (75%) was controlled with intravenous antibiotics. Driveline infection identified in 4 (50%) was treated successfully with local wound dressing changes and intravenous antibiotics. One 9-year-old boy died of rejection at 16 months after transplantation.

Conclusions

Because of the organ shortage, pediatric patients have a low chance to undergo HTx. VAD provides long-term support for children with end-stage heart failure before a suitable heart becomes available. A thromboembolic event remains a major complication influencing their survival.     

Amiodarone therapy before heart transplantation as a predictor of thyroid dysfunction after transplantation.

BACKGROUND: In recent years we have observed new cases of thyroid disease occurring after heart transplantation (HTx). In these patients, the presence of this disease complicates their post-transplant course and occasionally results in life-threatening thyrotoxicosis. The present study examines the incidence and risk factors of thyroid disease in these patients with special emphasis on the use of amiodarone before HTx. Recommendations for follow-up of thyroid disease in HTx patients are discussed. METHODS: A study was performed on a cohort of 380 patients who received HTx in Rotterdam between January 1, 1985 and April 1, 2001. Twenty patients (5%) developed thyroid dysfunction after HTx, 10 of whom had been treated with amiodarone before HTx. RESULTS: Cumulative survival curves showed that most patients (60%) developed thyroid dysfunction within the first year after HTx (median interval between HTx and diagnosis was 9 months). Using univariate Cox regression analysis, amiodarone was a significant predictor for the development of thyroid dysfunction (hazards ratio 5.2, 95% confidence interval 2.5 to 10.8). After adjustment for age, gender, heart disease and Quetelet index, amiodarone remained a significant predictor. CONCLUSIONS: Our study clearly shows that, despite discontinuation of amiodarone treatment at the time of the HTx procedure, patients remain at risk for developing thyroid disease. HTx recipients treated with amiodarone before HTx should therefore be monitored carefully for development of thyroid dysfunction, especially within the first post-transplant year.     

Left ventricular assist devices as bridge to heart transplantation: The Niguarda Experience

BACKGROUND: Congestive heart failure is the leading cause of death in Western countries. Heart transplantation currently is the only accepted therapy for patients with end-stage heart failure, but the supply of donor hearts is inadequate, and different mechanical circulatory support systems have been investigated as bridges to heart transplant. METHODS: Since April 1992, 53 patients (47 men, 6 women, aged 12 to 61 years) received left ventricle mechanical circulatory support as bridge to heart transplant. The two principal devices used were: the Novacor LVAS in 31 patients and the DeBakey VAD in 11 patients. RESULTS: All patients survived the operation. Mean duration of LVAD support was 2.8 +/- 5.6 months. Thirty-seven patients (71.1%) underwent heart transplantation. Twelve major bleeding episodes occurred in nine patients (16.9%). Globally, major and minor neurologic events occurred in 13 patients (24.5%). Ten patients (19.9%) assisted with the Novacor Wearable LVAS device were discharged at home while waiting for heart transplant (HTx). The mean follow-up of the 34 discharged transplanted patients was 45.3 +/- 37 months. Actuarial survival of transplanted patients while on LVAD was 91.0 +/- 4.9% and 83.4 +/- 8.5% at 1 and 5 years, respectively. No differences in post-transplant long-term survival and rejection and allograft vasculopathy occurred between patients transplanted with or without LVAD implanted. CONCLUSIONS: LVAD therapy proved to be effective in bridging patients with end-stage heart failure to HTx. While on LVAD support, patients assisted with implantable wearable devices could be discharged at home, ameliorating their quality of life. The excellent survival rate after HTx is concomitant with a low incidence of rejection and cardiac allograft vasculopathy.     

Renal function and outcome after heart transplantation

Objectives

To investigate whether measured glomerular filtration rate (mGFR) is a risk factor for death and/or end-stage renal disease (ESRD) after heart transplantation (HTx).