CLINICAL-EVALUATION OF THE HEARTPAK - A NEW PNEUMATIC PORTABLE DRIVERFOR USE WITH THE HEARTMATE IMPLANTABLE PNEUMATIC LEFT-VENTRICULAR ASSIST SYSTEM

The HeartPak(TM) Portable Pneumatic Driver was designed for use with t he HeartMate(R) Implantable Pneumatic Left Ventricular Assist Device ( IP-LVAS) (Thermo Cardiosystems, Inc., Woburn, MA). The HeartPak measur es 48 x 23 x 15 cm, weighs 9.3 kg with batteries, and can be carried b y a handle, by a shoulder strap, or on a trolley. Four 12 V batteries provide power for as long as 8 hr. To test the HeartPak in the hospita l environment, seven men were studied who were bridge-to-transplant pa tients (mean age, 59.8 +/- 8.87 years) undergoing HeartMate IP-LVAS th erapy. They were supported by the HeartPak for 429 days with a cycle c ount of 57,826,560. To normalize the mean pump flow rate, we used the body surface area to obtain a pump now index in each case. The mean fl ow rate was 2.65 +/- 0.57 L/min/m(2) for the HeartPak vs. 2.64 +/- 0.4 5 L/min/m(2) for the HeartMate 1000, the conventional driver previousl y used in these patients. The only potentially serious problem with th e HeartPak was console failure in one case. The patient took appropria te backup measures, and the HeartPak was replaced. In no case did the device cause any adverse effects or interruption of LVAS support. Comp ared with HeartMate 1000, the HeartPak was more convenient, easier to operate, and allowed better patient mobility.