Left ventricular outflow tract obstruction: is it the valve or something else?

A 67-YEAR-OLD FEMALE presented to the authors’ institution for an elective aortic valve replacement (AVR) in the setting of known aortic stenosis and progressive congestive heart failure symptoms. The patient had been followed as an outpatient with serial transthoracic echocardiograms (TTE) but suffered an acute episode of hemodynamic decompensation with respiratory failure requiring intubation and ventilation prior to this admission. At that time, it was determined that the patient would undergo elective aortic valve replacement (AVR). On the day of the surgery after uneventful induction of general anesthesia, an intraoperative transesophageal echocardiography (TEE) examination was performed with an iE-33 ultrasound system and an X7-2t probe (Philips Medical Systems, Andover, MA) capable of real-time three-dimensional (RT-3D) imaging. This evaluation revealed a discreet echo density in the left ventricular outflow tract (LVOT) (Fig 1) with associated turbulence on color-flow Doppler interrogation. There was also a significant gradient across the LVOT (Peak Gradient 48 mmHg) (Fig 2). There was mild-to-moderate aortic regurgitation (AR). The aortic valve leaflets were thickened with slightly limited excursion but did not appear to be significantly stenotic (Fig 3).