Letter to the Editor Dynamic left ventricular outflow tract obstruction secondary to catecholamine excess in a normal ventricle

Hypertrophic cardiomyopathy (HCM) is the most common cause of left ventricular outflow tract (LVOT) obstruction. The LVOT obstruction is a consequence of the asymmetric septal hypertrophy and the mitral systolic anterior motion (SAM), causing both of them a dynamic gradient in LVOT. LVOTobstruction has been observed also in other conditions like hypertensive hypertrophy, dehydration, sepsis, vasodilatation, excessive sympathetic stimulation, pericardial tamponade, and after mitral valve repair and aortic valve replacement for aortic stenosis. We report in this document the case of two patients who developed a significant gradient at LVOT in the context of amine treatment during their admission into the intensive unit care. In both, cases there were no gradient, significant hypertrophy or SAM at baseline cardiac evaluation. We have met only one case reported in the literature matching those conditions. In order to treat this type of patients properly, it is essential to take in consideration this pathology. D 2005 Elsevier Ireland Ltd. All rights reserved.