Unicuspid aortic valve with ascending aortic aneurysm: a rare cause of heart failure in a middle-aged male

A 51-year-old European male with a history of hypertension presented with a 3-week history of progressive exertional dyspnoea, orthopnoea and paroxysmal nocturnal dyspnoea. There was no chest pain, smoking or relevant family history. Examination revealed a blood pressure rate of 220/160mmHg, a heart rate of 110bpm, jugular venous distension, diastolic murmur, basal crackles and peripheral oedema.

Investigations showed left ventricular hypertrophy on ECG and pulmonary oedema on chest X-ray. Troponin I was mildly elevated (49–51nmol/L), and NT-proBNP was 1823pmol/L. Transthoracic echocardiogram (TTE) revealed a mildly dilated left ventricle (5.6cm), severe global dysfunction (LVEF 24%), unicuspid aortic valve (UAV) with moderate-to-severe stenosis (AVA 1.1cm², mean gradient 19mmHg, velocity 3.1 m/s, DVI 0.26) and moderate regurgitation. Ascending aorta was dilated (53mm). Pulmonary artery systolic pressure was estimated at 60–65mmHg.

He was treated with intravenous furosemide, fluid restriction and heart failure medications including spironolactone, perindopril and metoprolol. Coronary angiography was normal. Right heart catheterisation revealed mean RA pressure of 2mmHg, mean PA pressure of 23mmHg, and PCWP of 11mmHg. After 2 weeks of optimisation, cardiac MRI showed improvement in LVEF to 34% and aortic regurgitant fraction of 16%. A computed tomography (CT) confirmed ascending aortic aneurysm and UAV.

View Figure 1–2.

The patient underwent a successful Bentall procedure with the placement of a 21mm On-X mechanical valve conduit. His post-operative recovery was uneventful. A follow-up TTE showed the prosthetic valve in situ with LVEF improved to 45–50%. He was discharged on day 10.

UAV is an exceptionally rare congenital anomaly, affecting approximately 0.02% of adults, but is found in 4–5% of patients undergoing surgery for isolated aortic stenosis. It results from incomplete separation of aortic valve cusps during embryogenesis. UAV exists in two forms: acommissural (severe stenosis early in life) and unicommissural (asymptomatic until the third to fifth decades). UAV is more common in males and is associated with aortic aneurysm, dissection and regurgitation.

Diagnosis relies on imaging, with TTE and cardiac MRI playing key roles. The hallmark of UAV on imaging is a teardrop-shaped systolic orifice. Treatment is surgical, with guidelines recommending aortic root replacement if the ascending aorta exceeds 5.0cm in diameter.

This case highlights the importance of recognising rare congenital causes of heart failure in middle-aged adults and the need for timely surgical intervention to prevent life-threatening complications.