Abstract
Acute renal artery embolism (RAE) is a clinical rare condition and diagnosis of it is often delayed or missed due to both the rarity of the disease and its non-specific clinical presentation. The exact role and optimal timing of endovascular revascularization remain controversial and uncertain. This article discusses a case of acute renal artery embolism caused by atrial fibrillation. Endovascular renal thrombus aspiration combined with local low-dose thrombolysis reversed the renal ischemia with restoration of renal function despite prolonged ischemia.
1
Introduction
Acute renal artery embolism (RAE) is a rare clinical condition and diagnosis of it is often delayed or missed due to both the rarity of the disease and its non-specific clinical presentation. In addition to systemic anticoagulation, system thrombolysis and open surgery, percutaneous endovascular interventional therapy has been reported in treating patients with acute renal ischemia. The exact role and optimal timing of endovascular therapy remain controversial and uncertain. This case presents successful catheter aspiration combined with local low-dose thrombolysis in an acute renal artery occlusion and illustrates the potential benefits of renal artery revascularization despite prolonged ischemia.
2
Case report
A 52-year-old male with a history of sick sinus syndrome and paroxysmal atrial fibrillation was admitted to our hospital for pacemaker replacement. The patient had not been treated with Coumadin because his CHA2DS2-VASc scoring was only one. The patient had a DDD pacemaker implanted 8 years prior to the present hospitalization. On physical examination, his blood pressure was 120/60 mmHg with a heart rate of 60 beats per minute and respiratory rate of 18 breaths per minute. His baseline serum creatinine was 0.97 mg/dL (reference range 0.6–1.3 mg/dL) and glomerular filtration rate (GFR, Cockroft-Gault) was 78 mL/min. Screening laboratories, including a complete blood count and chemistry panel, were within normal limits. Before the procedure he complained acute right-sided abdominal and lumbar pain associated with hypertension (160/100 mmHg) by hospital day 2. Abdominal CT scan showed cholecystitis and left kidney calculus. The CT scan results may be merely tomographic findings without clinical significance in that they disagreed with clinical symptoms and physical examination results. Administrating atropine and antibiotic medicine did not relieve the patient of the symptom. Urine analysis was positive for protein and blood. Serum Lactate dehydrogenase (LDH) was 212 U/L (normal range, 100–280 U/L) at presentation, and found to be elevated at 709 U/L 72 h after abdominal pain. Repeat laboratories revealed a leukocytosis with a white cell count of 15.9 * 109/L (reference range 4.4–11.0 * 109/L) and mild renal insufficiency with a serum creatinine level of 1.7 mg/dL and GFR of 45 mL/min. An ECG showed new atrial fibrillation. Given the nature of the pain and the hematuria seen on urinalysis and the history of atrial fibrillation, renal ischemia was strongly considered as causes for this acute pain. Therefore contrast-enhanced helical computed tomography (CT) images [ Figs. 1 a,b ,c] were obtained 36 h after abdominal pain attacked, which showed extensive infarction involving the upper pole of the right kidney with multiple patchy infarcts into the lower pole.
Selective renal angiogram and endovascular intervention were then attempted through femoral approach. After an intravenous bolus of heparin (6000 U), a 8F MP (Multi Purpose, Cordis, USA) guiding catheter was used to engage the ostium of right renal artery, in order to offer a good support in case of provisional renal stent implantation. Angiogram [ Fig. 2 a ] showed total occlusion in main trunk of the right renal artery consistent with large thrombus. A 0.014 inch wire (Field, ASHAI, Japan) was passed through occlusive segment to distal artery as far as possible with the purpose of sufficient support, and a 6F thrombus aspiration catheter (Thrombuster II, Kaneka Corporation, Japan) was introduced along the guidewire. Repeated aspiration resulted in improved, ante-grade flow but incomplete recanalization [ Fig. 2 b]. Then a 250,000 U bolus of urokinase diluted to 10 mL in a mixture of saline was manually infused for five minutes through the guiding catheter. There was restoration of flow in renal artery on completion angiography [ Fig. 2 c]. The catheter was removed and hemostasis was accomplished with a vascular closure device. The patient’s abdominal pain completely resolved after procedure. His serum creatinine peaked at 2.4 mg/dL and GFR dropped into 2.4 mL/min. Anticoagulation therapy was begun, including low molecular heparin and Coumadin. Contrast-enhanced helical computed tomography was rechecked one week later. The images showed good contrast-enhanced in the lower pole but still incomplete filling in the middle and upper pole of the right kidney [ Figs. 3 a,b ,c]. When international normalized ratio was therapeutic, he was discharged and prescribed Coumadin.
