A 39-year-old woman was emergently referred to our hospital with dyspnea, tachypnea, elevated serum creatinine and urea (9.7 mg/dl and 173.5 mg/dl respectively), and refractory hypertension (190/85 mmHg). The patient was initially admitted to another hospital for flash pulmonary edema and deterioration of her previously medically controlled hypertension The patient was known with hypercoagulopathy (positive for Factor V G1691A (FV-Leiden) mutation) and single-functioning left kidney with previously treated stenotic left renal artery by balloon-expandable stent placement (12 months ago). The right renal artery was occluded, according to digital subtraction angiography (DSA). She was regularly followed up by a nephrologist, with a relatively stable serum creatinine level at 1.3 mg/dl, and was systematically prescribed clonidine, nifedipine, and acetylsalicylic acid (ASA).
Prior to her referral to our hospital’s Interventional Radiology Unit, a duplex ultrasound (DUS) was performed, which demonstrated a markedly increased flow velocity within the proximal left renal artery, with a maximal velocity above 350 cm/s, along with aliasing artefacts within the stent, which appeared to be occluded. The intrarenal resistance index was also markedly reduced. The right kidney was morphologically diminished in size with concomitant loss of cortical thickness. The diagnosis of over 48 h, acute renal ischemia (ARI) was made and taking into consideration the radiological findings, in addition to the patient’s young age and gravely impaired renal function, a multidisciplinary team concluded that urgent endovascular treatment was appropriate. The patient was treated with intravenous heparin infusion during hospitalization, which was stopped 12 h prior endovascular treatment.
Following skin antisepsis at the right groin with povidone-iodine solution scrub, administration of prophylactic intravenous antibiotics (cefazolin) and local anesthesia, a right common femoral artery access was obtained using a 6F sheath. “A bolus intra-arterial dose of unfractionated heparin 5000 IU was administrated through the sheath. Standard heparinized saline was used during the procedure.” Angiography with a pigtail catheter within the aorta at the level of the renal arteries depicted occlusion of the right renal artery and occlusion of the stent at the origin of the left renal artery (Fig. 1 a). However, the renal artery distal to the stent remained perfused by collaterals and appeared patent at delayed DSA images (Fig. 1 b). The occluded stent was successfully catheterized using a 5Fr USL 2 catheter (Cordis, USA) and in-stent thrombus was depicted (Fig. 1 c). A bolus dose of rtPA 5 mg was administrated through the catheter within the thrombus. The lesion was then surpassed using a 0.018 in. guide wire (V18, Boston Scientific, USA), and angioplasty was performed with a 5.5 × 40 mm, low-profile, mono-rail, angioplasty balloon catheter (Submarine Rapido; Invatec S.p.A, Italy) (Fig. 2 a). During balloon angioplasty, the patient experience left flank pain, and the looped V18 guide wire was noted to be erroneously advanced within the distal renal branches (Fig. 2 b, c). During the final DSA, extravasation of contrast media was depicted at the site of guide wire manipulation, but also at multiple sites of the kidney irrelevant to guide-wire distal migration and therefore attributed to reperfusion injury (Fig. 3 a). The patient’s flank pain increased remarkably, the systolic blood pressure dropped from 190 mmHg to 120 mmHg, and a significant sub capsular hematoma was noted during parenchymal phase DSA (Fig. 3 a). Nephron-sparing, ultra-selective, coil embolization was performed (Fig. 3 b, c) using a microcatheter (Progreat, Terumo, Japan) and by deploying two pushable 3 × 40 mm and 3 × 70 mm micro-coils (Nester, Cook, USA). However, following embolization extravasation was still noted, at the site of guide wire trauma while all the other sites of extravasation were not depicted (Fig. 3 c). The feeding branch was catheterized with the microcatheter and another pushable 3 × 140 mm micro-coil was deployed (Fig. 3 d). The vessel appeared occluded at fluoroscopy with minimal contrast infusion, and final DSA was not performed as the operator was convinced that the bleeding was stopped and further contrast media administration was deemed unnecessary and harmful to the already compromised renal function. Supportive conservative treatment was initialized, and the patient was transfused with three units of blood and remained hemodynamically stable.
After 12 days, the patient was discharged with normal blood pressure, serum creatinine level of 2.8 mg/dl, urea 115.2 mg/dl, and hemoglobin 10.2 mg/dl along with electrolytes within normal range. After 1 month, the creatinine level was 2.1 mg/dl, which after 3 months returned to nearly baseline value of 1.5 mg/dl. The patient was prescribed dual antiplatelet therapy (clopidogrel 75 mg and aspirin 100 mg once daily) for 1 year and was scheduled for a strict clinical and DUS follow-up at 1, 3, 6, and 12 months. After 1 year of follow-up, the stent remains patent and the patient is asymptomatic with stable renal function.