Dynamic Assessment of Mitral Valve Repair by Directing Pump Blood into the Left Ventricle

Abstract

Intraoperative testing has a major role in the evaluation of the results of mitral valve repair. Static evaluations are possible by inspecting the valve. Once the patient is weaned from cardiopulmonary bypass, dynamic assessment can be done by digital palpation through a partially closed left atriotomy or pressure monitoring or by transoesophageal or epicardial echocardiography. Before weaning off cardiopulmonary bypass, dynamic assessment is possible by injection of cold saline or cardioplegic solution into the left ventricle either by a catheter advanced through the aortic valve or through a left ventricular apical vent. Another method is by connecting the apical vent to the arterial line of the cardiopulmonary bypass by short side tubing. Repeated clamping and unclamping of this side tubing and the vent suction tubing will divert the arterial blood into the left ventricle under adequate pressure to test the dynamic function of the valve. This method leads to sudden partial diversion of the pump flow towards the left ventricle and absent vent flow. The perfusion technologist should be aware of this method and make appropriate adjustments in the pumping procedure.