A 39-year-old man with no relevant past medical history was evaluated for progressive light headedness, exertional dyspnea and chest pain. Transthoracic echocardiography (TTE) revealed a severely stenotic unicuspid aortic valve (AV), with mean and peak pressure gradients of 48 and 96 mmHg, respectively and AV area of 0.8 cm 2 . Moderate aortic regurgitation was also present. The coronary angiogram was normal. The patient was scheduled for an aortic valve replacement. Intraoperative transesophageal echocardiography (TEE) confirmed the presence of a stenotic unicuspid AV with a single commissure located posteriorly [Figure 1], [Panel a]. The ascending aorta was mildly dilated with normal sinuses of Valsalva and sinotubular junctions [Figure 1], [Panel b]. Three-dimensional TEE revealed a characteristic, teardrop-shaped eccentric valve orifice with a unicommissural, unicuspid AV [Figure 1], [Panel c] [Video 1] . Upon examination, the unicuspid leaflet was fibrotic with focal calcifications [Figure 2]. The valve was excised and replaced with a 23 mm mechanical valve. The patient had an uneventful recovery from the procedure.
Figure 1: 2-dimensional transesophageal echocardiographic images on the midesophageal aortic valve (AV) short axis (Panel a) and midesophageal AV long axis (Panel b) show the commissure of the valve and the stenotic orifice. A 3-dimensional transesophageal echocardiographic image (Panel c) en face view of the AV confirmed the findings
A unicuspid aortic valve is a rare congenital abnormality, with reported incidence of 0.02% in patients undergoing echocardiographic studies.  These valves may be unicommissural, with the commissural attachment to the aorta situated posteriorly in the majority of cases, or acommissural with no attachment to the aorta. The valve orifice in unicommissural valves is eccentric and elongated; while in acommissural valves it is central and pinhole-shaped. The acommissural variant is usually symptomatic at birth or during childhood, whereas the unicommissural type usually develops symptoms until adulthood. Both types are prone to early degeneration, causing aortic stenosis and regurgitation. Unicuspid AV is also frequently associated with dilation of the ascending aorta and aortic aneurysm. 
Chu JW, Picard MH, Agnihotri AK, Fitzsimons MG. Diagnosis of congenital unicuspid aortic valve in the adult population: The value and limitation of transesophageal echocardiography. Echocardiography 2010;27:1107-12. [PUBMED]
Correspondence Address: Mario Montealegre-Gallegos Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, One Deaconess Road, CC-470, Boston, MA 02215 USA
Source of Support: None, Conflict of Interest: None