The Pierce-Donachy ventricular assist device as a bridge to cardiac transplantation.

The Pierce-Donachy ventricular assist device (VAD) was used as an attempted bridge to orthotopic cardiac transplantation in 12 patients aged 13 to 55 years. Ischemic (4 patients), dilated (4 patients), acute viral (1 patient), postpartum (1 patient), and hypertrophic cardiomyopathy (1 patient), along with a failed transplant (1 patient), were the causative factors of end-stage cardiomyopathy in these patients. All patients were candidates for orthotopic cardiac transplantation but sustained refractory cardiogenic shock (cardiac index less than 2 L/min/m2). Left VADs were placed in all patients; 7 also required right VADs. Four patients died of hemorrhagic complications less than 24 hours after VAD insertion. Ventricular assist device stabilization was successful in 8 patients and support ranged from eight hours to 64 days. Seven patients successfully underwent orthotopic cardiac transplantation. One died postoperatively of hemorrhagic complications, 6 were discharged from the hospital, and 1 patient died at 3 months of cytomegalovirus infection. Five patients are long-term survivors. The Pierce-Donachy VAD is an effective means for supporting critically ill patients with end-stage cardiomyopathy and cardiogenic shock before orthotopic cardiac transplantation. Death is related to hemorrhagic, rather than infectious or thromboembolic, complications. Patients successfully stabilized with the VAD can undergo orthotopic cardiac transplantation with acceptable mortality and morbidity rates.

Effect of perioperative myocardial infarction on survival of postcardiotomy patients supported with ventricular-assist devices.

Ventricular-assist devices (VAD) have increased survival in patients with postcardiotomy shock, but the predictors of success need to be elucidated. We evaluated 45 patients treated with centrifugal (n = 18) or pulsatile (n = 27) VAD for postcardiotomy cardiogenic shock to determine the effect of perioperative myocardial infarction (PMI) on survival. The patients ranged in age from 15 to 72 years (mean age, 55.1 years). VAD support was left ventricular in 29, right ventricular in seven, and biventricular in nine, and the flow-rate range was 1.6-5.2 l/min (mean rate, 3.97 l/min) for 0.2-22 days (mean time, 4.1 days). PMI was determined by analysis of postoperative electrocardiogram (EKG), enzyme levels, or at necropsy. PMI was considered "possible" if there were either EKG or enzyme level changes, and "definite" if there were EKG and enzyme level changes or necropsy evidence. Of the 45 patients, 19 were successfully weaned from ventricular assistance; 12 were discharged (Group 1), and seven died (Group 2); the remaining 26 patients could not be weaned from VAD support (Group 3). In Group 1, one patient had a definite PMI, and three had a possible PMI. Among the 33 nonsurvivors (Groups 2 and 3), 24 patients had PMI by necropsy examination. Definite PMI was much more common in nonsurvivors (72.7%) than in survivors (8.3%) (p less than 0.05). However, Group 2 nonsurvivors were weaned despite PMI in 100% of cases. These data suggest that, although PMI is a strong negative determinant of survival in postcardiotomy patients, it cannot be considered a contraindication because it does not preclude myocardial recovery.

Determinants of survival in patients with ventricular assist devices.

Mechanical ventricular assist devices (VADs) have led to survival in patients who develop postcardiotomy cardiogenic shock (PCCS) refractory to conventional therapies. To elicit determinants of survival, the authors reviewed records of 26 patients at our institution who required Pierce-Donachy VADs for PCCS. Thirteen patients were weaned from ventricular assistance (50%), nine (34.6%) achieved long-term survival, and 17 died. Survivors and those that died were equivalent in terms of age, sex, NYHA class, type of operation, and preoperative hemodynamics. Ventricular assist pumping was established earlier in survivors (P = 0.006) although aortic cross-clamp and total cardiopulmonary bypass times were equivalent between the groups. The development of biventricular failure was significantly associated with the inability to wean from mechanical circulatory assistance. Despite an equal incidence of biventricular failure, survivors had milder forms of this entity and all patients with severe biventricular failure requiring a biventricular assist device failed to wean and ultimately died (N = 5). Of all complications, inadequate cardiac output was a significant determinant of weaning. Perioperative myocardial infarction and renal failure were found to be univariate determinants of survival. Inadequate cardiac output and biventricular failure preclude weaning from mechanical circulatory assistance. Survival is associated with the expeditious establishment of assist pumping, and with the avoidance of irreversible perioperative myocardial injury and renal failure.

Clinical experience with centrifugal pump ventricular support at UCLA Medical Center.

The experience using the vortex centrifugal pump as a ventricular assist device at The University of California, Los Angeles and Wadsworth V.A. Medical Centers is reviewed. Thirteen adult and one pediatric patients were supported postcardiotomy, 10 LVAD, 3 BIVAD, and 1 RVAD. There were no equipment failures over a mean perfusion time of 52 hr (range 12-140 hr). Seven of thirteen adult patients were supported and weaned from 6 LVAD and 1 BIVAD. Three patients underwent orthotopic heart transplantation, and the other four recovered ventricular function, of whom five are longterm survivors at a mean followup time of 16 months. In one patient bridged to transplantation, a prior infection caused the patient to succumb after successful transplantation. All patients assisted for transplantation are carefully screened, and would be excluded from transplantation if they developed significant infection, or irreversible renal or neurologic limitations.

Left heart and biventricular bypass.

Various forms of circulatory assist devices are currently under investigation. Clinical use of ventricular bypass devices ranging from roller-pump-driven units to pneumatically powered VADs have been in use for several years. These devices are indicated for patients in cardiogenic shock following cardiac surgery or myocardial infarction when all other forms of conventional therapy have failed. Success, though modest, is encouraging in these patients with a dismal prognosis. An increasing role for the VAD may be found in supporting patients whose condition deteriorates while awaiting cardiac transplantation.