F.D. Pagani

Predictors of Death and Transplant in Patients With a Mechanical Circulatory Support Device: A Multi-institutional Study

BACKGROUND INTERMACS is a registry of FDA-approved durable mechanical circulatory support (MCS) devices used for the strategies of destination therapy (DT) and bridge to transplantation (BTT) or recovery. This study identifies predictors for death and transplantation based on initial results from INTERMACS. METHODS From June 23, 2006 to December 31, 2007, 420 patients from 75 institutions were prospectively entered into the INTERMACS database in which pre-implant data, indication for MCS device use, adverse events, demographics, hemodynamics, laboratory values and outcomes were recorded. Using competing outcomes methodology, risk factors were identified for the events of death and transplantation. RESULTS The devices included 314 left ventricular assist devices (LVADs), 5 right VADs (RVADs), 77 biventricular VADs (biVADs) and 24 total artificial hearts (TAHs) for a total of 497 pumps in 420 patients. Among the BTT patients at 6 months, 33% were alive with a device in place, 42% were transplanted, 22% had died, and 3% were explanted for recovery. Among the DT patients at 6 months, 68% were alive with a device in place, 5% were transplanted, 25% had died, and 2% were explanted for recovery. The risk factors identified for death across all patient groups include older age (relative risk [RR] = 1.41, p < 0.001), ascites (RR = 2.04, p = 0.003), increased bilirubin (RR = 1.49, p < 0.05) and INTERMACS Level 1 (cardiogenic shock) (RR = 1.59, p = 0.02). The most common causes of death were central nervous system (CNS) event (18.3% of deaths), multiple-organ failure (16.4%) and cardiac cause (right ventricular failure and arrhythmias, 15.4%). CONCLUSIONS Cardiogenic shock, advanced age and severe right heart failure manifested as ascites or increased bilirubin are risk factors for death after MCS therapy. BTT patients who require biVAD support have a transplant rate similar to that of LVAD-only patients, but their mortality at 6 and 12 months exceeds that of LVAD-only patients. Consideration should be given to MCS referral before the sequelae of right ventricular failure dominate the advanced heart failure syndrome.

Mechanical circulatory supportPredictors of Death and Transplant in Patients With a Mechanical Circulatory Support Device: A Multi-institutional Study

BACKGROUND INTERMACS is a registry of FDA-approved durable mechanical circulatory support (MCS) devices used for the strategies of destination therapy (DT) and bridge to transplantation (BTT) or recovery. This study identifies predictors for death and transplantation based on initial results from INTERMACS. METHODS From June 23, 2006 to December 31, 2007, 420 patients from 75 institutions were prospectively entered into the INTERMACS database in which pre-implant data, indication for MCS device use, adverse events, demographics, hemodynamics, laboratory values and outcomes were recorded. Using competing outcomes methodology, risk factors were identified for the events of death and transplantation. RESULTS The devices included 314 left ventricular assist devices (LVADs), 5 right VADs (RVADs), 77 biventricular VADs (biVADs) and 24 total artificial hearts (TAHs) for a total of 497 pumps in 420 patients. Among the BTT patients at 6 months, 33% were alive with a device in place, 42% were transplanted, 22% had died, and 3% were explanted for recovery. Among the DT patients at 6 months, 68% were alive with a device in place, 5% were transplanted, 25% had died, and 2% were explanted for recovery. The risk factors identified for death across all patient groups include older age (relative risk [RR] = 1.41, p < 0.001), ascites (RR = 2.04, p = 0.003), increased bilirubin (RR = 1.49, p < 0.05) and INTERMACS Level 1 (cardiogenic shock) (RR = 1.59, p = 0.02). The most common causes of death were central nervous system (CNS) event (18.3% of deaths), multiple-organ failure (16.4%) and cardiac cause (right ventricular failure and arrhythmias, 15.4%). CONCLUSIONS Cardiogenic shock, advanced age and severe right heart failure manifested as ascites or increased bilirubin are risk factors for death after MCS therapy. BTT patients who require biVAD support have a transplant rate similar to that of LVAD-only patients, but their mortality at 6 and 12 months exceeds that of LVAD-only patients. Consideration should be given to MCS referral before the sequelae of right ventricular failure dominate the advanced heart failure syndrome.

Heart and Lung Transplantation in the United States, 1997-2006

This article highlights trends in heart and lung transplantation between 1997 and 2006, drawing on data from the OPTN and SRTR. The total number of candidates actively awaiting heart transplantation declined by 45% over the last decade, dropping from 2414 patients in 1997 to 1327 patients in 2006. The overall death rates among patients awaiting heart transplantation declined over the same period. The distribution of recipients among the different status groups at the time of heart transplantation changed little between the inception of the new classification system in 1999 and 2005. Deaths in the first year after heart transplantation have steadily decreased. At the end of 2006, 2885 candidates were awaiting a lung transplant, up 10% from the 1997 count. The median time‐to‐transplant for listed patients decreased by 87% over the decade, dropping from 1053 days in 1997 to 132 days in 2006. Selection for listing and transplantation has shifted toward more urgent patients since the May 2005 implementation of a new lung allocation system based on survival benefit and urgency rather than waiting time. Only 31 heart‐lung transplants were performed in 2006, down from a high of 62 in 1997.

Physiologic and Pathologic Changes in Patients with Continuous-Flow Ventricular Assist Devices

The clinical use of the newer continuous-flow pumps for mechanical circulatory support have resulted in superior outcomes including significantly reduced complication rates with improved durability over first generation pulsatile design pumps. However, as with all new technology, the newer LVADs have introduced a different set of management issues, as well as a unique risk profile into the mechanical circulatory support arena that were previously absent or unimportant with pulsatile LVADs. These include the effects of continuous flow on the systemic circulation and end-organ function, risk of thromboembolism, and pump thrombosis related to contact bearings in the blood path, the possible increased incidence of gastrointestinal bleeding, and ventricular arrhythmias, as well as alterations in the unloading characteristics of continuous-flow devices. This manuscript overviews the physiologic and pathologic effects that are associated with continuous-flow pumps and their unique management issues and complications.

Report From the American Society of Transplantation Conference on Donor Heart Selection in Adult Cardiac Transplantation in the United States

Cardiac transplantation remains the only definitive treatment for end‐stage heart failure. Transplantation rates are limited by a shortage of donor hearts. This shortage is magnified because many hearts are discarded because of strict selection criteria and concern for regulatory reprimand for less‐than‐optimal posttransplant outcomes. There is no standardized approach to donor selection despite proposals to liberalize acceptance criteria. A donor heart selection conference was organized to facilitate discussion and generate ideas for future research. The event was attended by 66 participants from 41 centers with considerable experience in cardiac donor selection. There were state‐of‐the‐art presentations on donor selection, with subsequent breakout sessions on standardizing the process and increasing utilization of donor hearts. Participants debated misconceptions and established agreement on donor and recipient risk factors for donor selection and identified the components necessary for a future donor risk score. Ideas for future initiatives include modification of regulatory practices to consider extended criteria donors when evaluating outcomes and prospective studies aimed at identifying the factors leading to nonacceptance of available donor hearts. With agreement on the most important donor and recipient risk factors, it is anticipated that a consistent approach to donor selection will improve rates of heart transplantation.

Significant reduction in major LVAD device failures: comparison of the heartmate® VE and XVE LVAS

Background: Left ventricular assist device (LVAD) is an established surgical therapy for patients with end-stage heart failure (HF) as a bridge to heart transplantation (HTx). Pulsatile LVAD clinical application is limited by large dimensions, noise and major complications as bleeding, thromboembolism and infection. We report our clinical experiences with the DeBakey VAD continuous axial flow pump as bridge to HTx (BTT). Patients and Methods: Since April 2000, 12 patients with end-stage HF have been supported with the DeBakey VAD at our Institution (8 male, 42 14 years, range 12-57 y; 8 dilated idiopathic cardiomyopathy, 3 ischemic cardiomyopathy, 1 for major device failure of a pulsatile LVAD implanted at another institution). Before implant all patients suffered for severe heart failure (NYHA IV) despite of maximal pharmacological support and were put on the waiting list for HTx. All patients signed written informed consent. Mean cardiac index was 1,58 0,52 l/min/m2. Results: Total support time amounts to 607 patient/days. Nine patients (75%) were successfully transplanted after 51 49 days (range 11 -141 days). Two patients (16.6%) died during assistance due to multiorgan failure. One patient is still on VAD. No patients needed right-VAD. Bleeding complications required rethoracotomy in 2 patients (16.6%), neurologic event occurred in 1 patient, left ventricle/LVAD thrombosis occurred in one patient and was succesfully conservatively treated with endoventricular thrombolysis delivering rTPA into the left ventricle. No clinically relevant elevation of plasma-free hemoglobin was detected. No device, driveline or abdominal pocket infection occurred. No device failure occurred. Conclusions: In our clinical experience the axial continuous flow DeBakey VAD obtained an elevated rate of success associated with low risk for bleeding, hemolysis, thromboembolic and infectious complications.

Considerations on afterload management for patients with centrifugal ventricular assist devices.

This case report illustrates the challenges in managing patients with centrifugal ventricular assist devices (VADs). As these devices have evolved, their physical properties have changed, impacting patient management. Levitated centrifugal pumps have a non-linear response to afterloads. The device output will decrease significantly in the presence of high systemic vascular resistance. Blood pressure control is integral to the management of patients in the immediate and later postoperative period.

Scoring system determines successful RVAD explant following BiVAD support: implications for destination therapy

average time to discharge was 13.3 days. Postoperative courses following LVAD replacement were shorter than those following initial LVAD implantation. ICU stays were decreased by 3.7 days (43%) and total hospital stays were decreased by 14.6 days (52%). Outcomes tended to be better in those who underwent abdominal only approaches (mortality 0 of 8, 0%) versus those who also underwent sternotomy (mortality 3 of 8, 47%). Conclusions: In this experience, the largest reported to date, LVAD replacement was undertaken with acceptable outcomes, including shortened postoperative courses. Further improvements in outcomes will be important as LVAD replacement is made commonplace by durations of support exceeding the life expectancies of current technology.

Does INTERMACS Classification Predict Outcomes after LVAD Implantation

Purpose: Since continuous flow left ventricular assist devices (CF-LVAD) became a standard care for end-stage heart failure patients, it is still a challenge to implant CF-LVAD for smaller size patients. We analyzed mid-term outcomes of these patients. Methods: CF-LVADs were implanted in 73 patients (15 female, 40±13 year-old, 51 dilated cardiomyopathy) for the purpose of bridge to heart transplantation (HTx) (BTT) and implanted devices were HeartMateII in 36, EVAHEART in 17, Jarvik2000 in 10, DuraHeart in 9 and HeartWare in 1.The average body surface are (BSA) was 1.65±0.19 m2 (1.22-2.07). These patients were divided into two groups, standard group (BSA> 1.6m2, n= 43) and small group (BSA≤ 1.6m2, n= 30). Mid-term clinical outcomes and data collected from post-implant echocardiography and catheter examination (obtained from 63 patients) were compared between two groups. Optimal LVAD pump speed was set by clinical parameters including echocardiography. Results: The average support period was 1.7±1.1 years (0.1-4.3). Postimplant catheter data showed no significant difference between two groups in cardiac index (2.9±0.6L/m2 in small group, 2.8±0.5L/m2 in standard group, p= 0.27) and mean pulmonary pressure 14±4 mmHg, 16±6 mmHg, p= 0.10). Echocardiography at 1 month showed left ventricular dimension was significantly reduced in both group and there were no significant difference between two groups (18±15%, 14±17%, p= 0.29). There were no operative deaths and 4 late deaths due to cerebrovascular accident (CVA) in 3 and right heart failure in 1. Oneand 2-year survival rate (censored by HTx and recovery) for overall patients were 97% and 95%, respectively, and there were no significant difference between two groups (Log-rank test, p= 0.59). CVA were recorded in 24 patients and 1and 2-year freedom from CVA were 68% and 62%, respectively, and there were no significant difference between two groups (p= 0.49). Serial echocardiography showed that 1and 2-year freedom from mild or greater aortic regurgitation were 84% and 63% and there were no significant difference between two groups (p= 0.60). Conclusion: CF-LVAD provided excellent clinical outcomes for small size patients in terms of survival and hemodynamics. There were no significant difference between small size patients and standard size patients.