Severe Calcific Bicuspid Aortic Valve Stenosis Presenting as Reversible Complete Heart Block.

BACKGROUND

Severe calcific bicuspid aortic valve (BAV) stenosis rarely presents with complete heart block, although extensive subvalvular calcium may compress the atrioventricular conduction axis.

CASE SUMMARY: A 42-year-old man presented with presyncope and dyspnea, and his electrocardiogram showed complete atrioventricular dissociation with a ventricular escape rhythm. Echocardiography and computed tomography aortography demonstrated severe calcific type 0 BAV stenosis, with dense calcium extending into the membranous septum. Surgical aortic valve replacement with a mechanical prosthesis was performed. Postoperatively, the patient showed progressive restoration of intrinsic conduction, and temporary pacing wires were removed by day 6. At 3-month follow-up, he remained asymptomatic in stable sinus rhythm with a well-functioning prosthetic valve.

DISCUSSION: This case highlights severe calcific BAV stenosis as an uncommon but reversible cause of complete heart block.

TAKE-HOME MESSAGE: Early recognition of this mechanism is essential to prevent unnecessary permanent pacemaker implantation and underscores the value of multimodality imaging in evaluating conduction abnormalities.