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A paracorporeal left ventricular assist device (LVAD) with a capacity to pump 8 L/min of blood was employed in a clinical trial, and this report details the first survivor. A 60-year-old man could not be separated from the pump oxygenator following coronary artery bypass grafting, and, therefore, an LVAD was employed. Almost the entire left ventricular workload was assumed by the mechanical pump so that the myocardium was allowed to rest and recover. The LVAD support was continued for 105 hours. It provided satisfactory total body perfusion with maintenance of good hemodynamics—without serious deleterious effects on hematologic factors. The patient is alive and active without cardiac symptoms 16 months after his operation. The total experience with 13 LVAD implantations warrants continuation of the clinical trials in selected patients. (JAMA243:46-49, 1980)

In a previous study, the survival time of transfused erythrocytes was determined in dogs before and after total body perfusion with a pump oxygenator. 1 In that study, pooled homologous blood taken from the oxygenator and tagged with chromium survived longer in the perfused, thoracotomized dogs than in the control dogs not operated on. Survival time of the homotransfused tagged red blood cells in the perfused animals, however, was still shorter than the survival time in dogs transfused with their own blood. Further experiments in which a dog's own blood was run through the oxygenator without the addition of homologous blood showed that trauma to the erythrocytes in itself specifically accounted for a decrease of approximately 6 days in survival time. There are 2 possible explanations for the relative prolongation of survival time in the perfused dogs. One is that the perfused animal contributed approximately 25% of his own red

USING A COMBINATION of hemodilution and hypothermia, DeWall and Lillehei 1 have shown that patients subjected to extracorporeal circulation exhibit no ill effects from the decreased oxygen capacity of perfused blood. Apparently the oxygen supplied is sufficient at this lower temperature to maintain adequate tissue oxygenation. Dilution of the blood reduces the requirement for large quantities of donor blood. Boerema et al 2 have shown that animals can survive without blood cells in a chamber supplied with air at three times normal atmospheric pressure. The success of either of these techniques depends on a supply of oxygen sufficient to maintain aerobic metabolism under the experimental conditions. Youmans et al, 3 however, have demonstrated that animals can survive complete cessation of cerebral blood flow for periods as long as 30 min. They stopped cerebral flow by raising cerebrospinal fluid pressure, while the rest of the body remained well oxygenated. Wolfe 4

There have been several reports on the effectiveness of protamine and hexadimethrine (Polybrene) in neutralizing the effects of heparin. Parkin and Kvale 1 showed in rabbits with no extracorporeal circulation that clotting times returned to normal at a 1.5:1 dose of protamine to heparin in 5 minutes. In 1953, Preston and Parker 2 reported on the effects of hexadimethrine on the clotting time in peptone shock and in experimental radiation injury. They found that in the normal animal 7.5 mg. hexadimethrine neutralized 10 mg. of heparin in vivo. In peptone shock, when the coagulation time was prolonged to 56 minutes or more, hexadimethrine in doses of 0.9 to 2.2 mg. per kilogram restored the coagulation time to approximately control levels within a few minutes. In vitro studies showed that the shortest clotting time occurred when the amount of protamine and heparin exactly neutralized each other. If either was in excess

The majority of unresolved problems in the present era of heart surgery are biologic rather than technical. The advances made in total body perfusion, the improvement in the protection of the myocardium in artificially induced cardiac arrest, etc., have made it possible to deal quite successfully with several types of congenital and acquired heart anomalies. The operative results, however, are still discouraging if the procedure is aimed not only at repair of a defect, but at replacement of a malfunction or destroyed vital structure of the heart, as well. A practical application of this problem is the surgical management of valvular incompetence. Valvular insufficiency can be successfully repaired in some instances by valvuloplasty. In most cases, however, the calcific degeneration of the valve tissue makes plastic correction futile. The only effective way to handle such situations seems to be the complete excision and replacement of the valvular apparatus. Different materials

Operable Heart Disease is a clear, succinct monograph which presents many parts of this expanding subject in a valuable way for the pediatrician in training and the practitioner. Section I, titled "General Considerations," includes separate chapters on such subjects as routine diagnostic radiology, special diagnostic procedures, pulmonary hypertension, the physiology of total cardiopulmonary bypass, and preoperative and postoperative management, to name the ones most likely to give practical guidance to practitioners. Dr. Sirak in discussion of radiology and diagnostic procedures clarifies current surgical opinion on evaluation of clinical problems for pediatricians and other physicians. He presents, as his past work led us to expect of him, an excellent discussion of pulmonary hypertension. The reader will have a clear understanding of the effect of pulmonary vascular disease on determination of operability. The last two chapters of Section I summarize the essentials of the physiologic basis of total body perfusion and postoperative