Dynamic left ventricular outflow tract obstruction in the setting of acute anterior myocardial infarction: a serious and potentially fatal complication?

Dynamic left ventricular outflow tract (LVOT) obstruction was thought to be a hallmark of hypertrophic obstructive cardiomyopathy, especially in those cases with isolated asymmetric septal hypertrophy and systolic anterior motion (SAM) of the mitral valve. Recently, several authors described the occurrence of a dynamic LVOT obstruction during acute coronary insufficiency in ventricles without significant myocardial hypertrophy. The LVOT gradient was reported to disappear following resolution of the ischemic syndrome.

Modifications of Oxygen Saturation During Transesophageal Echocardiography.

The present study was designed: (1) to establish the effects of transesophageal echocardiography (TEE) on arterial oxygen saturation (SAO(2)%); (2) to verify the possible clinical consequences of this phenomenon; and (3) to study the possibility of predicting modifications of SAO(2)% by clinical or hemodynamic variables or by specific factors related to the TEE procedure. We prospectively studied 116 unselected patients, aged 61 +/- 12 years, who underwent diagnostic TEE for various clinical indications. Thirty-seven patients had mitral valve disease, 19 aortic valve disease, 14 combined mitroaortic disease, 8 congenital heart disease, and 38 other cardiovascular diseases.