Iatrogenic vascular lesions after minimally invasive partial nephrectomy: A multi-institutional study of clinical and renal functional outcomes

Objectives: To report the first large multi-institutional experience, including clinical and renal functional outcomes after treatment of iatrogenic vascular lesions (eg, renal artery pseudoaneurysm, arteriovenous fistula). These lesions are uncommon after minimally invasive partial nephrectomy (MIPN) but can be associated with significant morbidity. Methods: A retrospective review of MIPN was performed at 4 centers. Patients developing pseudoaneurysm or arteriovenous fistula in the postoperative period were identified. The demographic, disease, and perioperative details and data regarding the presentation and treatment of vascular lesions were collected. Results: Of the 998 patients undergoing MIPN, 20 (2.0%) presented with iatrogenic vascular lesions (17 with pseudoaneurysm and 3 with arteriovenous fistula). The mean age was 55.9 years, the tumor size was 2.6 cm, and the body mass index was 30.8 kg/m². Twelve patients (60%) had >50% endophytic tumors, 7 patients (35%) had undergone collecting system repair, and the mean warm ischemia time was 26 minutes. All patients presented with gross hematuria at a mean of 14.5 days postoperatively. The diagnosis was made using urgent computed tomography scan in all cases. Selective embolization was performed in 16 patients; 2 required no intervention and had spontaneous resolution, and 2 had negative angiography findings. Four patients required transfusion during rehospitalization. Although 4 patients had categorical worsening of the glomerular filtration rate after MIPN, all patients had stable function acutely after angioembolization, and 3 patients had categorical glomerular filtration rate improvement through a mean follow-up of 20 months. No patients had recurrent hemorrhagic events. Conclusions: Iatrogenic vascular lesions occur in ∼2% of MIPN cases. Although a subset of patients will have resolution with observation only, most require angioembolization, with excellent clinical and renal function outcomes.