A decade of experience with a left heart assist device in patients undergoing open intracardiac operation

Abstract

Over a decade has elapsed since the first clinical application of our left heart assist device (LHAD). The basic concepts underlying its development evolved from prior experience in which, given adequate support time, less than total left heart bypass (LHB) was found to result in gradual improvement of depressed left ventricular function. Hence, the long‐held view that functional recovery of the heart could occuronlyunder conditions of total LHB seemed unsupportable by clinical realities. As a result, a simple LHAD was devised. Requiring only special silicone elastomer cannulas, the system uses a roller (or other continuous flow) pump and diverts blood from the left atrium to the ascending aorta. We believe a major asset of the system is the ability to separate the patient subsequently from the LHAD without need to re‐enter the thorax. This is accomplished by permanently occluding each cannula lumen with an obturator, thereby allowing the biocompatible cannulas to remain permanentlyin situ.To date, 27 patients have undergone LHAD support. Of 18 patients who could be separated from the device, half (9) were discharged from the hospital. Seven remain alive and well, the longest now more than 10 years after the operation. Although rarely needed, broadening operative indications in patients with severely compromised left ventricular function suggests that there will be continued need for a method of LHB for the foreseeable future.

The Spindle Pump—A Nonpulsatile Blood Pump for Assisted Circulation

“…Advantageous were its simple construction, the increased efflciency and the easy handling, not to forget the numerous problems with the membrane pumps [136][137][138][139]. On one hand, the roller pump was further developed for assisted circulation [140][141][142][143][144][145]. On the other hand, technical improvements on both pumps mentioned [146][147][148][149] and the construction of new pulseless systems attempted to either minimize or eradicate the above problems [150][151][152][153][154][155][156][157].…”