Ruptured Sinus of Valsalva Aneurysm With Fistulous Communication to the Pulmonary Artery Revealing Behçet's Disease.

We present the case of a 32-year-old South Asian male patient with a four-day history of cough, fever, and haemoptysis who was found to have a ruptured sinus of Valsalva aneurysm (SoVa) with a fistulous connection to the pulmonary artery. Examination revealed tachycardia and a loud murmur with thrills over the pulmonary area, along with features of pulmonary oedema. Nasopharyngeal polymerase chain reaction (PCR) test confirmed COVID-19 infection. Transthoracic echocardiography demonstrated turbulent left-to-right shunting at the great artery level, mild functional mitral and tricuspid regurgitation, and elevated pulmonary artery systolic pressure. Computed tomography pulmonary angiography identified a ruptured SoVa with a fistulous connection to the pulmonary artery, associated right upper lobe pulmonary embolism, and pulmonary congestion. Initial management included corticosteroids and antivirals for COVID-19, broad-spectrum antibiotics for suspected infective endocarditis, and diuretics. Progressive cardiac dysfunction necessitated percutaneous closure of the fistula using an 8-mm occluder device, achieving prompt haemodynamic stabilisation. Subsequently, the patient developed severe aortic regurgitation, aortic root dilatation, and right ventricular dysfunction, requiring urgent aortic root replacement with a tissue prosthesis and right ventricular repair. Persistent postoperative pyrexia and elevated inflammatory markers despite sterile blood cultures prompted histopathological evaluation, which revealed necrotising granulomatous inflammation with multinucleated giant cells, which couldn't rule out giant-cell aortitis. A rheumatological review uncovered recurrent oral and genital ulceration, confirming Behçet's disease as the underlying aetiology. Immunosuppressive therapy with corticosteroids, infliximab, and azathioprine, together with treatment for latent tuberculosis (TB), resulted in full clinical remission. At one-year follow-up, ventricular function and prosthetic valve performance remained preserved with no evidence of recurrent aneurysmal change or inflammatory activity. This case highlights the complex interplay between structural cardiac pathology, infection, and systemic vasculitis, underscoring the importance of multidisciplinary evaluation and targeted immunosuppressive therapy.