Duplicate inferior vena cava complicating the evaluation of primary aldosteronism.

A 64-year-old man with a known duplicate inferior vena cava (D-IVC) and resistant hypertension presented to our emergency department in a hypertensive crisis. He had a longstanding history of hypertension and unexplained hypokalemia treated with oral potassium supplementation. The patient was diagnosed with primary aldosteronism and MRI of the abdomen revealed a left-sided adrenal adenoma. Adrenal venous sampling (AVS) lateralised aldosterone hypersecretion to the left adrenal gland. The patient subsequently underwent an uncomplicated laparoscopic left adrenalectomy. The patient's postoperative course was uneventful, and he was discharged on a single antihypertensive medication on postoperative day 1. D-IVC is one of several rare IVC anatomical variants that have been well described in the literature. Knowledge of this patient's unique abdominal venous anatomy enabled successful AVS and appropriate surgical management. It is necessary to identify potential anatomical variants of abdominal venous anatomy that may complicate these invasive procedures.