Aortic Fenestration for Type B Chronic Aortic Dissection Complicated with Lower Limb Malperfusion Induced by Walking Exercise

Abstract

We report a case of a 55-year-old male with type B-chronic aortic dissection. Patient presented with intermittent claudication due to limb malperfusion resulting from expansion of a patent false lumen during walking regardless of normal range ankle-brachial index (ABI) at rest. Preoperative stress vascular ultrasonography was an effective modality for proper diagnosis. We should be concerned of reversible ischemia due to the dissection fl ap in patients with type B aortic dissection. Fenestration of the aorta can be a choice of treatment in such patients. The patient has been doing well with no ischemia for 3.5 years after the operation. Key words: chronic aortic dissection, aortic fenestration, limb malperfusion Case ReportA 55-year-old man with a history of type B aortic dissection suffered 1.5 years ago, presented with intermittent claudication was referred to our hospital. The ABI of this patient at rest in the supine position was within the normal range. Right ankle-brachial index (ABI) was 1.07, left one was 1.05. However, the ABI worsened after walking exercise (Fig. 1a). Right ABI turned down to 0.55, left ABI turned down to 0.57.Intermittent claudication started at distance of approximately 50 meters.Computed tomography revealed that the false lumen was patent and that a dissection fl ap extended to the terminal aorta. The true lumen was compressed by the false lumen and was narrowed.Mobile fl ap was detected near the terminal aorta by vascular ultrasonography, and blood fl ow to the bilateral limb was maintained without decrease in the ABI. However, a stress vascular ultrasonography performed after a 6-min walking exercise revealed that the subtotal occlusion of the true lumen in the terminal aorta caused by the expansion of a patent false lumen (Fig. 2). Furthermore, blood fl ow to the bilateral limb was reduced with simultaneous decrease in bilateral ABI.We performed surgical resection of the fl ap in the terminal aorta under laparotomy. During the procedure, the dissection fl ap was found extended to 15 mm in the proximal position to the terminal aorta bifurcation. The distal edge was blind with a mural thrombus, though a small re-entry was present (Fig. 3). After fenestration, aortotomy was closed with 4-0 Prolene sutures reinforced with a 10-mm-width felt strip.His symptom resolved following the operation. Achievement of functional recovery by this surgical treatment was confi rmed by a stress ABI (Fig.1b) and stress vascular ultrasonography performed after a 6-min walking exercise. Thermography after a walking test showed increased blood fl ow in the lower extremities, compared to the fl ow before the test. Enhanced computed tomography revealed

Repeated Peripheral Embolisms associated with Chronic Aortic Dissection

“…The main mechanism of ischemic complications is compression of a true lumen by extension and expansion of a patent false lumen, inducing occlusion, or thrombosis in the aorta or branch arteries. [1][2][3][4] However, in our patient, renal infarction and leg ischemia occurred in the chronic phase of type B AD and resulted from embolism. According to a systematic review of 138 patients with type B AD and lower limb malperfusion (LLM), the LLM developed in the chronic phase in only four patients (3%) and in the acute phase in 134 patients (97%), and no case of LLM caused by embolism was reported.…”

“…Approximately one-third of patients with AD are complicated by visceral, renal, spinal cord, and/or limb ischemia, which increase the risk of early death. 1,2 Most ischemic complications occur during the acute phase of the disease, and are rare in patients with chronic AD. The main mechanism of ischemic complications is compression of a true lumen by extension and expansion of a patent false lumen, inducing occlusion, or thrombosis in the aorta or branch arteries.…”

“…Aortic dissection (AD) can be complicated by rupture, aneurysm formation, valve dysfunction, or organ ischemia. Among these morbidities, ischemia affects approximately 30% of patients with AD, 1,2 and mostly occurs during the acute, not chronic, phase of the disease. The extension and expansion of a false lumen that compresses a true lumen is a main cause of occlusion of the aorta and its branches, [1][2][3][4] whereas ischemic complications attributed to other mechanisms are seldom identified.…”

JCS/JSCVS/JATS/JSVS 2020 Guideline on Diagnosis and Treatment of Aortic Aneurysm and Aortic Dissection

“…Endovascular treatments for aortic aneurysm/dissection other than TEVAR/EVAR include endovascular fenestration for true lumen stenosis or malperfusion and bare metal stent placement in the true lumen. [475][476][477][478][479][480][481] For recommendations and details, see "3. Stanford Type B Aortic Dissection" in Chapter VI.…”