A new catheter mounted, transvalvular left ventricular assist device has been designed for percutaneous transfemoral access. The device, the Hemopump [14 French (Fr.) outer diameter], is based on a mixed flow rotary pump and is capable of flow rates of 1.5-2.2 l/min. The pump is inserted using a specialized 16 Fr. femoral introducer sheath. The first application of the percutaneous Hemopump in man was performed in two patients with hemodynamic compromise during high risk coronary angioplasty. In these patients, Hemopump support resulted in hemodynamic stabilization (increase in aortic pressure from 60/42 to 87/61 and from 80/60 to 100/70 mm Hg, respectively) and marked left ventricular unloading (decrease in pulmonary capillary wedge pressure from 25 to 10 and from 14 to 10 mm Hg) during balloon inflation. In both patients, percutaneous transluminal coronary angioplasty (PTCA) could be accomplished successfully. Using the system for periods of about 2 hr in each patient, we observed no vascular, hemorrhagic, or embolic complications. In both patients, only a minor increase in both plasma free hemoglobin and lactate dehydrogenase levels was noted. Our preliminary experiences suggest that the percutaneous Hemopump is safe and effective and may be a powerful alternative to other devices used for supported angioplasty.

We report the case of a 75-year-old patient who suffered from subacute myocardial infarction and severely impaired left ventricular ejection fraction (EF: 17%). Using a novel 16F left ventricular assist device we performed an angioplasty of the right coronary artery, and of the left anterior descending artery. As a result of the circulatory support the patient recovered from cardiogenic shock within 8 hr. At a pump speed of 45,000 rpm the axial flow pump generated flow rates up to 3.3 l/min. The 16F pump cannula was removed using local compression. The EF was 51% at 30-day follow-up examination.

Cardiopulmonary bypass (CPB) with cardioplegic myocardial preservation has long been the gold standard for surgical care of coronary artery disease. More recently, alternatives to the conventional approach of CPB-myocardial revascularization have been developed. Epicardial stabilizing devices have been used to immobilize areas of the beating heart to provide a stable surface for some coronary anastomoses. These approaches are often limited to anterior aspects of the heart because revascularization of posterior and lateral vessels often requires the heart to be manipulated or contorted. Excessive manipulation can lead to hemodynamic compromise as a result of partially obstructing pulmonary blood flow. A miniature extracorporeal system has been developed that uses right ventricular support and allows for epicardial surgical procedures to be conducted on a beating heart without standard CPB. The extracorporeal system consists of a coaxial atrial cannula that is connected to a miniature centrifugal pump. Blood is drained from the right atrium, passes through the miniature centrifugal pump and is delivered through the cannula's inner reinfusion lumen into the pulmonary artery. The entire circuit volume is approximately 30 ml. The system is positioned on the sterile operative field. The pump is controlled by a console positioned adjacent to the patient. The centrifugal pump is capable of delivering blood flow at rates of 1-6 l/min. This extracorporeal system may be of benefit in maintaining adequate cardiac output during epicardial beating heart surgery.

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