First use of the Molecular Adsorbent Recirculating System technique on patients with hypoxic liver failure after cardiogenic shock.

The Molecular Adsorbent Recirculating System (MARS) has been proven to prolong survival in patients with hepatorenal syndrome. MARS is a modified dialysis that uses an albumin containing dialysate, which is recirculated and perfused online through charcoal and anion exchanger columns. It allows the selective removal of albumin bound substances. Despite advances in medical therapy and technology, the prognosis of patients with cardiogenic shock remains poor. Mortality rates are as high as 80%, often because of persistent multiple organ failure. To determine whether patients with hypoxic liver failure after cardiogenic shock after cardiac surgery might benefit from MARS, we performed a prospective, randomized, controlled, single center study. The primary objective was to prove that MARS improves survival. This article is a report on the interim analysis of the first 27 patients included between August 2000 and December 2001; 14 patients were in the MARS group, and 13 patients were in the non-MARS group. All had bilirubin levels greater than 8 mg/ml. Both groups had a similar risk profile. The MARS group received MARS for 3 consecutive days-if bilirubin was still greater than 6 mg/dl afterward, MARS was continued. The non-MARS group received conventional therapy. We had seven survivors in the MARS group (50%) compared with four (32%; p = ns) in the non-MARS group. We conclude that despite the limited number of patients included in this analysis, MARS can be recommended for patients with acute, hypoxic liver failure because it might prolong survival. Further studies in similar patient cohorts are needed to verify our results.

Differential indication for mechanical circulatory support following heart transplantation.

PURPOSE: We describe our experience with ventricular assist devices (VAD) in patients with cardiogenic shock refractory to pharmacological therapy and support using intraaortic balloon pump after cardiac transplantation. PATIENTS: Between July 1987 and August 1997, 848 patients underwent cardiac transplantation in our hospital. INTERVENTIONS: Fifteen patients (1.8%) needed mechanical circulatory support for refractory cardiac failure due to right heart failure (six patients), primary graft failure (three patients), and acute rejection (six patients). Three pump systems were used: Biomedicus Centrifugal Pump, Abiomed BVS 500, and Thoratec VAD. The choice of system depended on the indication and quality of each device. Seven patients (47%) could be weaned from the mechanical circulatory support (MCS) system and three patients (20%) are long-term survivors. RESULTS: All 15 patients developed at least one serious complication, such as multiorgan failure (MOF), liver failure, acute renal failure or sepsis. Twenty-five per cent had severe bleeding and 13% had neurological complication. Mortality was due mostly to MOF, MOF and sepsis or sepsis. The survivors had a CI greater than 2.2 l.min.m2, total bilirubin less than 1.0 U/1, and did not undergo resuscitation. CONCLUSIONS: Heart failure after cardiac transplantation severe enough to require MCS is currently associated with several major complications and high mortality (80%).

Device and patient management in a bridge-to-transplant setting.

BACKGROUND: A variety of sophisticated devices have been developed for mechanical circulatory support in patients bridged to cardiac transplantation. Based on 13 years' experience, we have developed specific protocols for patient selection and management for different devices. METHODS: The principal systems applied in the bridge-to-transplant cohort are the Thoratec ventricular assist device (n = 144, mean duration of support 53 +/- 57 days), the Novacor left ventricular assist system (LVAS) (n = 85, mean duration of support 154 +/- 15 days), and the HeartMate LVAS (n = 54, mean duration of support 143 +/- 142 days). The Thoratec device is used for biventricular assistance or if the duration of support is expected to be less than 6 months. For long-term support, either the Novacor or HeartMate LVAS are preferred. RESULTS: Despite careful postoperative patient management, this group of patients is prone to a variety of complications. Bleeding occurred in 22% to 35%, right heart failure in 15% to 26%, neurologic disorders in 7% to 28%, infection in 7% to 30%, and liver failure in 11% to 20% of patients. Complications varied with the device applied and the patient's preoperative condition. A total of 73 patients were discharged from hospital for a mean period of 184 days; this cumulative experience amounted to 37.5 patient-years. CONCLUSIONS: The Novacor and the HeartMate systems offer the additional possibility of discharging patients during support if they fulfill certain criteria. The main reasons for rehospitalization were thromboembolic and infectious complications.

Predictors of survival in patients bridged to transplantation with the thoratec VAD device: a single-center retrospective study on more than 100 patients.

BACKGROUND: Careful patient selection markedly influences the outcome of patients who undergo mechanical circulatory support. Therefore, we tried to evaluate predictors of survival after implantation of the Thoratec ventricular assist device (VAD). METHODS: Between October 1992 and January 2000, 104 patients (86 men, 18 women, aged 11 to 69 years) received the Thoratec VAD as a bridge to transplant. A total of 51 patients required left ventricular support (LVAD), 50 patients required biventricular support (BVAD), and 3 patients required total artificial heart implantation. We performed univariate analysis of 25 parameters with regard to their effect on survival and then applied a multivariate analysis to evaluate those factors that turned out to be marginally significant. We performed all analysis for the total collective as well as for the LVAD and BVAD sub-group. RESULTS: The BVAD patients tended to have worse outcomes than did LVAD patients. We found no significant predictors of survival in either sub-group. In the total collective, however, we found the following pre-implant conditions were independent risk factors for survival after VAD implantation: patient age > 60 years (odds ratio [OR] 3.87, confidence interval [CI] 1.39 to 10.76), pre-implant ventilation (OR, 6.76; CI 2.42 to 18.84), and increased pre-implant total bilirubin (OR, 1.42; CL, 1.19 to 1.69). CONCLUSIONS: Transplant candidates on inotropic support should be considered for bridging to transplant as soon as bilirubin values start to increase or before respiratory function deteriorates and ventilation becomes necessary. In elderly patients, careful patient selection, particularly considering potential risk factors, might favorably affect their outcomes.

Novacor left ventricular assist system versus Heartmate vented electric left ventricular assist system as a long-term mechanical circulatory support device in bridging patients: a prospective study.

OBJECTIVE: Long-term mechanical circulatory support as a bridge-to-transplantation procedure and bridge to recovery is of increasing importance. The implantable left ventricular assist devices, Novacor N100 left ventricular assist system (Baxter Healthcare Corporation, Berkeley, Calif) and TCI HeartMate vented electric left ventricular assist system (Thermo Cardiosystems Inc, Woburn, Mass), have proved to be efficient devices in bridge-to-transplantation settings and for prolonged support. The two systems were compared with regard to reliability and morbidity. METHODS: Between October 1996 and March 1998, a prospective, single-center study was done that included 40 patients, 20 of whom were treated with the Novacor system and 20 of whom were treated with the HeartMate device. The diseases were mainly dilated cardiomyopathy (13/9) and ischemic cardiomyopathy (6/10). There were no statistically significant differences between the two groups regarding age, sex, preoperative clinical blood chemistry values, hemodynamic data, or risk factors. RESULTS: There were no statistically significant differences between the two groups with regard to postoperative hemodynamics, organ recovery, out-of-hospital support, and survival to heart transplantation. Mean duration of support was 235.3 +/- 210 days for the Novacor group and 174.6 +/- 175 days for the HeartMate group and mean out-of-hospital support was 241 +/- 179 days and 166 +/- 152 days for the two groups, respectively. Neurologic complications occurred significantly more often among the Novacor group, whereas the HeartMate group had a higher prevalence of infections and technical problems, which was statistically significant. Survival to transplantation was 65% for the Novacor group and 60% for the HeartMate group. CONCLUSIONS: Most patients had organ recovery with left ventricular assist system support, and a considerable number of patients in both groups underwent transplantation. However, both devices need revision to address the current problems, that is, thromboembolism for the Novacor device and infection and reliability for the HeartMate device.

Single-center experience with the thoratec ventricular assist device.

OBJECTIVE: The Thoratec ventricular assist device (Thoratec Laboratories, Pleasanton, Calif) is widely accepted for univentricular and biventricular support in patients with various indications. The aim of this study is to describe our experience with implantation of the Thoratec ventricular assist device in more than 100 patients. METHODS: From March 1992 to June 1998, 114 patients (98 men and 16 women; mean age, 47.9 years) received the Thoratec ventricular assist device for a mean duration of 44.9 days. The patients were divided into 3 groups. Group 1 included 84 patients in whom the system was applied as a bridge-to-transplant procedure. Group 2 included 17 patients with postcardiotomy cardiogenic shock, and group 3 included 13 patients with cardiogenic shock of other causes. RESULTS: Sixty-eight percent of patients in group 1 survived to transplantation with a posttransplant survival of 88%. The only independent risk factor affecting survival was age more than 60 years. Survivals in groups 2 and 3 were 47% and 31%, respectively. Main complications in all groups were bleeding, multiple organ failure, liver failure, sepsis, and neurologic disorders. CONCLUSIONS: The Thoratec ventricular assist device has proved to be a reliable device for bridge to transplantation and postcardiotomy support. Further studies are required on patient selection and on patient and device management to reduce the incidence of complications in these patient populations.

Temporary pulsatile ventricular assist devices and biventricular assist devices.

BACKGROUND: During the past years several systems for mechanical circulatory support have become available. In this study we describe our experience with short-term and mid-term application of the ABIOMED and Thoratec device. METHODS: Since 1990 the ABIOMED BVS and since 1992 the Thoratec VAD have been applied to 75 and 103 patients, respectively, with postcardiotomy heart failure, as a bridge-to-transplant procedure, and with different other indications. RESULTS: In the ABIOMED collective 25 of 50 patients (50%) with postcardiotomy heart failure and 1 of 4 patients with miscellaneous other indications could be discharged from hospital, 7 of 14 bridge-to-transplant patients (50%) underwent transplantation with a posttransplant survival of 86%. In the Thoratec collective 6 of 10 patients (60%) with postcardiotomy heart failure and 4 of 8 patients (50%) with miscellaneous indications could be discharged from hospital, 48 bridge-to-transplant patients (74%) underwent transplantation with a posttransplant survival of 90%. CONCLUSIONS: The results show the versatility of the Thoratec VAD for short-term and mid-term application in patients with postcardiotomy heart failure and as a bridge-to-transplant procedure. The use of the ABIOMED device is not indicated for bridging patients to transplantation. Although in case of postcardiotomy heart failure, Thoratec is also superior to ABIOMED, the high costs of the Thoratec VAD limits its wide acceptance in this patient cohort.

Bridging to cardiac transplantation with the Thoratec Ventricular Assist Device.

Mechanical circulatory support has become an established procedure for bridging patients to cardiac transplantation. One of the devices available is the Thoratec VAD, which can be applied for univentricular or biventricular support. Between March 1992 and June 1997, 74 patients were bridged with Thoratec VAD to cardiac transplantation. In 67 patients the system was applied exclusively (26 LVAD, 38 BVAD, 3 TAH), in 7 patients subsequently or in combination with another MCS device. 71.6% with exclusive Thoratec application underwent transplantation with a post-transplant survival rate of 90%, 4 patients are still waiting. Transplant rate in LVAD and BVAD patients was 84% and 71.4%, respectively, posttransplant survival 95.2% and 88%, respectively. 28.6% with a combined application of Thoratec and another MCS device survived to be discharged from hospital. Main complications were bleeding, liver failure, multiple organ failure, and infections. In terms of reliability and efficacy the Thoratec VAD is the system of choice for mid-term application in patients bridged to cardiac transplantation.

Cardiopulmonary resuscitation after cardiac surgery: a two-year study.

OBJECTIVE: The aim of this study was to investigate the incidence of cardiopulmonary resuscitation (CPR) after cardiac surgery and to find predictors of survival. DESIGN: A retrospective study with data obtained by chart review. SETTING: A university hospital 24-bed cardiac surgical intensive care unit (ICU). PARTICIPANTS: Between 1993 and 1994, 4,968 consecutive adult patients who underwent cardiac surgery at the authors' hospital were studied. INTERVENTIONS: None. MAIN RESULTS: One hundred thirteen of these patients (2.3%) were resuscitated. Seventy-nine patients (70%) survived to be discharged from the hospital. Significant predictors of survival were the time between admission to the ICU and initiation of CPR, CPR time, and creatine kinase (CK) and CK-MB values. CONCLUSIONS: The incidence of CPR after cardiac surgery was 2.3% with no difference between valve surgery and CABG. Best results were achieved when arrhythmias or bleeding were the predisposing causes. Further studies have to be undertaken concerning long-term results and quality of life of the discharged patients.

Long-term mechanical circulatory support.

Against the background of an increasing number of patients waiting for heart transplantation but a stagnating number of transplant procedures, long-term mechanical circulatory support is gaining major importance. We investigated the outcome of 20 patients (15 men, and 5 women, aged between 15 and 66 years) each supported for more than 100 days between September 1987 and August 1996. The indications for implantation were bridging in 17 patients, myocarditis in 2 patients, and postcardiotomy cardiogenic shock in one patient. 12 patients received the Novacor IVAD, 4 patients the Thoratec system, 3 patients the HeartMate device and one patient both Novacor and Thoratec. Mean duration of support was 178.1 days, 15 patients were transplanted, 14 of them could be discharged, 2 patients died, 4 patients are still waiting. The most frequent complication was device-related infection in 11 patients. The results have shown that all three systems are safe and reliable devices for supporting patients for more than 100 days.

Mechanical circulatory support: lessons from a single centre.

Over recent years, a number of different mechanical circulatory support (MCS) products have been developed to a stage where they are no longer investigational devices. Registry data provide some information, but this is limited by the mix of historical and contemporary data and the voluntary nature of the contributions. As yet, there are no clear guidelines for patient selection, the differential application of generically different devices or for optimal patient management. Ours is a busy centre offering a comprehensive cardiovascular service. This review details our experience since 1987 and 189 patients supported with five different types of device, used in all of the common applications. Our experience has permitted the formulation of some general principles and guidelines. Data published by registries and by individual manufacturers are, as yet, not standardized. We hope that our experience will be of interest to those centres wishing to establish a mechanical assist service.

Mechanical circulatory support with the Thoratec assist device in patients with postcardiotomy cardiogenic shock.

BACKGROUND: In spite of modern cardiac surgical techniques, severe cardiogenic shock not responding to pharmacologic therapy and intraaortic balloon pumping develops in about 0.2% to 1.2% of patients undergoing cardiac operations. METHODS: From September 1987 to September 1994, 184 patients were supported with different mechanical circulatory support systems. Nine patients with postcardiotomy cardiogenic shock were supported with the Thoratec ventricular assist device. Four patients suffered early postcardiotomy cardiogenic shock, and 5 patients suffered late postcardiotomy cardiogenic shock. In 6 patients the Thoratec device was applied exclusively, in 2 patients both Bio-Medicus and Thoratec, and in 1 patient both ABIOMED and Thoratec devices were used. Duration of support ranged from 5 to 46 days with a mean duration of 15 days. RESULTS: Four patients (44%) survived and were discharged. Main complications and causes of death were multiple organ failure and sepsis. CONCLUSIONS: The results justify the use of Thoratec assist device in patients with severe preoperative cardiogenic shock.

Seven years of experience with the centrifugal pump in patients with cardiogenic shock.

From September 1987 to September 1994 61 patients between 29 and 78 years of age received mechanical circulatory support by means of the Biomedicus centrifugal pump. The patients were divided into three groups by indication: Group I included 15 patients with early postcardiotomy cardiogenic shock and 24 patients with late postcardiotomy cardiogenic shock. Group II 11 patients with therapy-resistant cardiogenic shock following acute myocardial infarction, and Group III 11 patients with cardiogenic shock of other etiologies. Duration of support was 1 to 347 hours. Survival rates were 46.7% and 33.3% in patients with early and late postcardiotomy cardiogenic shock, respectively (Group I), 27.2% in Group II, and 18.1% in Group III. Most frequent complications were bleeding (40%, 58%) and acute renal failure (26.7%, 29.2%) in Group I and multiple organ failure in Groups II and III (64% and 45.5%). Major causes of death were bleeding and multiple organ failure in Group I (37.5%) and multiple organ failure in Groups II and III (87.5% and 50%). Groups II and III (87.5% and 50%).

Mechanical circulatory support: the Bad Oeynhausen experience.

From September 1987 to February 1994, we treated 147 patients ranging between 11 and 82 years old with different mechanical circulatory support systems. The applied devices were the Bio-Medicus centrifugal pump in 61 patients, the Abiomed BVS System 5000 in 49 patients, the Thoratec ventricular assist device in 42 patients, and the Novacor left ventricular assist device in 7 patients. On the basis of indication for mechanical circulatory support, the patients were divided into three groups: group 1 consisted of 72 patients with postcardiotomy cardiogenic shock; group 2, 50 patients in whom mechanical support was used as a bridge to cardiac transplantation; and group 3 (miscellaneous), 25 patients in cardiogenic shock resulting from acute myocardial infarction (n = 14), acute fulminant myocarditis (n = 3), primary graft failure (n = 2), right heart failure after heart transplantation (n = 3), and acute rejection (n = 3). Time of support ranged from 1 hour to 97 days (mean duration, 10.8 days). Seventy-five patients (51%) were discharged from the hospital. The best survival rate was achieved in group 2 with 72%, followed by group 1 with 44% and then group 3 with 28%. The most frequent complications in group 1 were bleeding (44%), multiple-organ failure (24%), neurologic disorders (18%), and acute renal failure (15%). In group 2, the major complications were bleeding (34%) and cerebrovascular disorders (22%) and in group 3, multiple-organ failure and sepsis (60%) and bleeding (32%).