Subacute aortic dissection presenting as heart failure due to aortic valve insufficiency and right coronary artery dissection.

Subacute thoracic aortic aneurysm dissection (TAAD) often presents with a clinical profile distinct from its acute form, which can closely mimic common cardiac conditions, risking diagnostic delay. We report a case of subacute TAAD presenting initially with progressive dyspnoea due to severe aortic regurgitation (AR), culminating in congestive heart failure with reduced left ventricular ejection fraction. Diagnosis was confirmed with CT angiography. Surgical repair was performed using the Hemi-Yacoub technique. The postoperative course was complicated by paroxysmal atrial fibrillation, which necessitated pacemaker implantation. At the 6-month follow-up, the patient demonstrates recovery of left ventricular ejection fraction to 50%. This case highlights the importance of considering aortic pathology in patients with heart failure of unclear origin, particularly when accompanied by a new diastolic murmur or echocardiographic evidence of significant AR.