Cardiac resynchronization therapy for low-flow, low-gradient aortic stenosis.

Low-flow, low-gradient aortic stenosis is a heterogeneous entity that encompasses truly severe aortic stenosis as well as mild-to-moderate aortic stenosis in which aortic valve orifice area is severely reduced primarily due to left ventricular (LV) contractile dysfunction. Under such circumstances the capacity of the LV to generate stroke-work is severely compromised. In this case report, we describe a patient with severe LV dysfunction and ventricular dyssynchrony due to right ventricular pacing who presented with decompensated heart failure in the setting of low-flow, low-gradient aortic stenosis. We discuss the management of this high-operative-risk patient, who ultimately underwent upgrading of his dual chamber pacemaker to a biventricular pacemaker with significant echocardiographic, haemodynamic, and clinical improvement.