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The percutaneous Hemopump showed beneficial effects during coronary angioplasty in 32 high-risk patients with unloading of the left ventricle during ischemia and maintaining cardiac output with mean aortic pressures of 50 mm Hg in case of cardiac arrest (3 patients). High procedure-related morbidity (occlusion of femoral artery in 2 patients; bleeding with need of transfusion in 4 patients) and mortality (4 of 32 patients) rates demonstrate the need for a very careful selection of patients.

Implantation of the wearable Novacor electrically powered left ventricular assist system was performed on March 16, 1993, in a 44-year-old man hospitalized for an acute episode of myocardial decompensation after a 6-year history of dilated cardiomyopathy. He was rehabilitated fully and became ambulatory, awaiting a suitable cardiac graft for 59 days. He is now back to work, enjoying a normal life. This case illustrates the progress made by miniaturization of the external components of the system. General acceptance of the system and psychological adaptation to the new way of life were remarkable.

Results obtained in the past 3 years in patients referred with acute myocardial infarction (AMI) and cardiogenic shock for a mechanical bridge to urgent transplantation permit one to assess the real impact of the present strategy in clinical practice. Ten patients (mean age = 49) were admitted in serious condition (CI = 1.8 +/- 0.2 L/min/m2, PCWP = 28 +/- 6 mmHg, systolic aortic pressure = 88 +/- 20 mmHg, urine output 11 +/- 20 ml/hr) and were treated by maximal sympathomimetic support and i.v. enoximone. Two had to be implanted with a total artificial heart (TAH) and one with a left ventricular assist device (LVAD) for recurrent fibrillation despite hemodynamic improvement, within 8 hr. Two have received transplants and are living well after 20 months. Seven who initially improved markedly have been listed as urgent transplant candidates: two of these have been successfully transplanted, and three died suddenly after 6, 25, and 45 days, respectively. One has undergone successful coronary surgery. One patient (age 62, diabetic) was secondarily rejected for a transplant and died. This experience clearly shows that despite initial spectacular hemodynamic improvement, which was due to optimized medical management, death rate before transplant because of sudden ventricular fibrillation remains unacceptably high. This should prompt early mechanical support, with less invasive systems, in patients with AMI.

Prophylactic implantation of a Hemopump (Johnson and Johnson, Skillman, NJ) has been evaluated in nine patients selected for high risk coronary angioplasty. They were unstable patients, refractory to maximal pharmacology, with indications for revascularization, but contraindications for surgery such as low ejection fraction and lack of material for bypass. In all, the target lesion was located on the last patent vessel. The pump was inserted under local anesthesia, without any graft. A specially designed occluder permitted avoidance of retrograde bleeding during implantation. The bypass flow ranged from 2.5 to 3.2 L/min, and permitted a rise in cardiac index from 2.05 to 2.55 L/min/m2, with a drop in capillary wedge pressure from 13 (7-18) to 10 (7-13) mmHg. During balloon inflation, no electrocardiographic changes were observed, because only minor ventricular arrhythmias occurred. No significant hemolysis was seen (plasma free hemoglobin less than 10 mg/dl in all) after 2 hr of pumping. The only limitation of the technique appears to be difficulty at the time of implantation from narrow, stenosed, or tortuous iliofemoral arteries (3 patients). This experience strongly supports the benefit of temporary left ventricular Hemopump support in high-risk situations and clearly shows the need for a smaller pump.

Patient selection and optimal timing for implantation are unsettled issues in candidates for a bridge to cardiac transplantation. A prospective evaluation of a strategy based on enoximone (E) given IV, in addition to sympathomimetic drugs, permitting to buy time, and delay by hours or days the decisions, has been performed from 1985 to 1988. Thirty-four patients in cardiogenic shock with hemodynamical criteria for TAH implantation have been included: Cl was 1.8 +/- 0.2 L/min/m2 PCWP 29 +/- 7 mmHg, diuresis less than 20 ml/hr. The protocol permitted to postpone decisions of implantation in 30 cases. The 4 unresponsive patients were implanted immediately with TAH (3) or VAD (1). Three were transplanted, two successfully. For 30, time given permitted discovery of hidden contraindications to transplantation in 17 patients. In 13, indication for transplantation was confirmed and performed in 11 within 6 hrs to 8 days (survival 64%). In two, sudden deterioration led to an unsuccessful TAH implantation. Multifactorial analysis showed that a 50% rise in Cl together with a 50% drop in PCWP, a 50% drop in PVR 30 min after IV E has a high predictive value of survival. These data suggest that enoximone IV bolus given in addition to maximal sympathomimetics to patients in cardiogenic shock reduces by 88% the need for TAH or VAD. It also permits a better selection of the candidates.