Anaesthetic Considerations for Noncoronary Surgery on a Perfused Beating Heart under Cardiopulmonary Bypass.

ABSTRACT

Myocardial revascularisation on a beating heart with or without cardiopulmonary bypass has significantly reduced the incidence of cardioplegic myocardial injury. With this advantage in view, noncoronary open heart surgery was performed on a beating heart under cardiopulmonary bypass. We discuss the anaesthetic management of such cases. Thirty-three patients aged 14-56 years underwent open heart surgery on a perfused beating heart. Eleven of them underwent open mitral valvotomy, eighteen underwent mitral valve replacement, repair of atrial septal defect was performed in 3 patients and one had removal of left atrial myxoma. Cardiopulmonary bypass was instituted with aortic and bicaval cannulation. At normothermia, aorta was cross-clamped and continuous coronary perfusion was maintained through an aortic root needle at a rate of 4-6 mL/Kg/minute facilitating a beating heart. Trans-oesophageal echocardiography was routinely deployed. Anaesthetic considerations were focused towards the maintenance of the beating state of the heart, that included, strict control of electrolyte balance, maintenance of adequate perfusion pressure and ST segment monitoring. All the patients could be weaned off cardiopulmonary bypass without defibrillation or significant inotropic support. There was no operative mortality. Open heart surgery on a beating heart for non-coronary cardiac conditions appears to be a good and reproducible option to protect the myocardium from deleterious effects of cardioplegic arrest.