Intra-aortic balloon counterpulsation in low cardiac output states

The role of mechanical devices

Devices to support the circulation and directly assist the ventricle during surgery are now both reliable and essential. The intraaortic balloon counterpulsation device is used in patients who fail to wean easily from cardiopulmonary bypass, who develop ischemia in the immediate postoperative period, or who have low output in the maximal edema phase, 4 to 8 hours postoperatively. Complications relate to the insertion of the device, which may cause major arterial disruption, lower leg ischemia, or distal arterial thromboemboli. Ventricular assist device (VAD) support is indicated when, despite the use of the intraaortic balloon, the patient's hemodynamics remain severely depressed and the patient is unable to wean from bypass. There are several contraindications to the use of VADs, including pulmonary hemorrhage. Nevertheless, as experience with the many different types of VADs increases, their use may be extended to periods of days or even months. Various mechanical support devices have been used to bridge to cardiac transplantation, with ranging degrees of success. Decisions concerning the use of mechanical devices for this purpose must take into account both the standard contraindications to transplantation, and contraindications that develop or are acquired during intervention with the bridging device. Current and future experience will decide which devices will be accepted for common clinical use.

Current management of patients after cardiopulmonary bypass

The postoperative management of cardiac surgical patients is reviewed with particular reference to some of the recent advances and current controversies. It is emphasised that there has been a marked decrease in the incidence of many of the major problems associated with cardiopulmonary bypass and that, in the majority of cases, cardiac surgery is now a routine procedure associated with a very low morbidity and mortality.

Methods and results of mechanical myocardial support

In recent years the development of modern direct techniques for revascularization surgery has resulted in a multitude of critically ill patients undergoing open heart surgery. To deal with the increasing numbers of patients who both require urgent open heart surgery and present with many complicated patterns of disease, a spectrum of cardiac assist measures, ranging from simple pharmacological interventions to mechanical cardiac assist techniques, has been developed. Those temporary mechanical cardiac assist devices which employ the principle of couterpulsation and balloon pummping have met with the most consistent clinical success. We now report our experience and progress in this field since early 19729