[Echocardiographic observation of intraoperative circulatory collapse in a patient with hypertrophic obstructive cardiomyopathy].

Two-dimensional Doppler echocardiography was used as an intraoperative cardiac function monitor in anesthetic management of a 79-year-old male with hypertrophic obstructive cardiomyopathy (HOCM) who underwent pulmonary lobectomy for lung cancer. Circulatory collapse occurred after thoracic epidural anesthesia (TEA), and was aggravated with following induction of general anesthesia. The collapse did not improve with phenylephrine nor atropine and necessitated ethylephrine and dopamine. During the above course, left ventricular outflow tract pressure gradient measured with continuous wave Doppler method was almost in proportion to cardiac output measured with thermo-dilution method. This means that TEA and the administration of inotropics did not worsen the left ventricular outflow tract obstruction. Left ventricular filling property estimated by trans-mitral flow velocity spectra improved when hemodynamics was stabilized with continuous infusion of dopamine, while it had been impaired during preoperative period and at the beginning of anesthesia. Our observation suggests that TEA for HOCM patient is a relative indication because it may exert negative inotropic effect, and that careful titration with inotropics is not contraindicated when undesired cardiac depression is proved by echocardiography.