Left ventricular outflow tract obstruction: the role of the modified Konno procedure

The progressive nature of obstruction in the left ventricular outflow tract (LVOT) is hypothesized to be related to the complex relationship between anatomic substrate, genetic predisposition, local shear stress, and the response to injury. Consequently, recurrent obstruction after resection of subaortic membranes as well as more complex forms of LVOT obstruction (eg, tunnel-like stenosis) require aggressive resection to provide unobstructed egress of blood from the left ventricle. The modified Konno procedure is well suited to provide maximal enlargement of the entire LVOT with preservation of aortic valve function. Extension of the procedure to patients with simple forms of LVOT obstruction is, at present, not warranted because of the inability to identify patients destined to develop recurrent obstruction. As predictive models improve, however, the modified Konno procedure should be evaluated in the setting of simple LVOT obstruction at high risk for recurrent obstruction.