Joseph S. Krakauer

Clinical management ancillary to phase-shift balloon pumping in cardiogenic shock: Preliminary comments☆

Abstract Intraaortic phase-shift balloon pumping was utilized in 30 patients in cardiogenic shock secondary to acute myocardial infarction who were refractory to conventional pharmacologic therapy. The outcomes in these cases suggested that the interval from myocardial infarction to onset of shock, rather than the duration of shock, may have a significant influence on the prognosis. Of 20 patients classified as having “early” shock, 3 died as a result of factors related to the procedure. Of the remaining 17 patients, the condition of 15 (88 percent) improved to the point that intraaortic balloon pumping could be discontinued. Nine of these patients were long-term survivors. Of 10 patients with delayed onset of shock, the condition of only 4 improved, and none left the hospital alive. Myocardial rupture was proved to have occurred in 5 of these patients, and suspected on clinical grounds in 1 patient. The clinical management essential to successful intraaortic balloon pumping is summarized.

Phase-shift balloon pumping in cardiogenic shock.

Abstract Twenty-one patients with intractable shock (in 20, secondary to myocardial infarction; in one, probably due to aneurysm-induced left ventricular pump failure) were treated with mechanical circulatory assistance utilizing an intraaortic balloon. In 16 patients circulatory failure developed within 36 hours of the onset of myocardial infarction. Shock was permanently reversed in 13 of these patients, and 5 were well 7 to 18 months after mechanical assistance; 2 long-term survivors died, one 19 months, and the other 7 months, after balloon pumping. In 5 patients in whom the onset of circulatory failure was delayed to 36 hours or more after myocardial infarction, shock was reversed during active mechanical assistance. The limiting factor in 4 of these patients was the natural evolution of the infarct to necrosis and myocardial rupture. In contrast, 18 patients, in whom mechanically assisted circulation was indicated but for various reasons could not be performed, died from shock. On the basis of this limited experience, we believe that mechanical circulatory assistance has a real therapeutic role in the treatment of intractable circulatory failure developing relatively early in the course of acute myocardial infarction. Its efficacy in so-called delayed circulatory failure requires further clarification.

Clinical experience with permanent mechanical circulatory assistance

Abstract 1.1. The implantation of a mechanical auxiliary ventricle is described in two patients, with severe refractory congestive heart failure. 2.2. The prosthetic device assisted the patients circulation for a period of 12 days of intermittent operation with no detectable damage. 3.3. There is evidence that clotting in the prosthesis was a result of excessively long arterial graft segments which can be eliminated due to redesign of the device. 4.4. The mechanical auxiliary ventricle has reached a stage of development where it can be considered practical for an intensive clinical trial in patients with near terminal congestive heart failure. 5.5. These trials will define the types of patients who can benefit most from this assist device and will allow the development of standardized surgical techniques and long-term operating criteria for the mechanical auxiliary ventricle.