Thanila A. Macedo

Vascular Ehlers-Danlos syndrome: Imaging findings

OBJECTIVE Vascular Ehlers-Danlos syndrome (EDS), formerly known as EDS type IV, is an autosomal dominant disorder characterized by fragility of medium and large arteries due to type III procollagen deficiency. Our purpose was to review the imaging findings in a cohort of patients with a diagnosis of vascular EDS. MATERIALS AND METHODS The radiologic, surgical, and genetic databases at a single multispecialty medical practice were reviewed for a 35-year period between 1971 and 2006. Thirty-three patients with a clinical diagnosis of vascular EDS were identified. Imaging studies were available for 28 patients, 13 men and 15 women, with a mean age of 39.8 +/- 16 years at the time of diagnosis. A vascular radiologist reviewed a total of 189 imaging examinations: 87 CT, 27 MRI, 59 sonography, and 16 angiography. RESULTS Vascular abnormalities were present in 22 (78%) of 28 patients. Arterial abnormalities included 41 aneurysms, 19 dissections, 12 ectasias, and 10 occlusions. There was one splenic vein aneurysm and one carotid cavernous fistula. Six patients had a total of 10 parenchymal infarcts involving the brain (n = 5), kidney (n = 3), and spleen (n = 2). Nine patients had 10 hemorrhagic events, five related to spontaneous vascular rupture and five associated with interventional or surgical procedures. Six patients had 13 nonvascular findings. CONCLUSION The most common findings were arterial aneurysms and dissections, followed by arterial ectasias and occlusions. Life-threatening complications included hemorrhage and infarcts.

Reinterventions for stent restenosis in patients treated for atherosclerotic mesenteric artery disease

OBJECTIVE Mesenteric artery angioplasty and stenting (MAS) has been plagued by high restenosis and reintervention rates. The purpose of this study was to review the outcomes of patients treated for mesenteric artery in-stent restenosis (MAISR). METHODS The clinical data of 157 patients treated for chronic mesenteric ischemia with MAS of 170 vessels was entered into a prospective database (1998-2010). Fifty-seven patients (36%) developed MAISR after a mean follow-up of 29 months, defined by duplex ultrasound peak systolic velocity >330 cm/s and angiographic stenosis >60%. We reviewed the clinical data, radiologic studies, and outcomes of patients who underwent reintervention for restenosis. End points were mortality and morbidity, patient survival, symptom recurrence, reintervention, and patency rates. RESULTS There were 30 patients (25 female and five male; mean age, 69 ± 14 years) treated with reintervention for MAISR. Twenty-four patients presented with recurrent symptoms (21 chronic, three acute), and six had asymptomatic preocclusive lesions. Twenty-six patients (87%) underwent redo endovascular revascularization (rER) with stent placement in 17 (13 bare metal and four covered) or percutaneous transluminal angioplasty (PTA) in nine. The other four patients (13%) had open bypass, one for acute ischemia. There was one death (3%) in a patient treated with redo stenting for acute mesenteric ischemia. Seven patients (27%) treated by rER developed complications, including access site problems in four patients, and distal embolization with bowel ischemia, congestive heart failure and stent thrombosis in one each. Symptom improvement was noted in 22 of the 24 symptomatic patients (92%). After a mean follow-up of 29 ± 12 months, 15 patients (50%) developed a second restenosis, and seven (23%) required other reintervention. Rates of symptom recurrence, restenosis, and reinterventions were 0/4, 0/4, and 0/4 for covered stents, 2/9, 3/9, and 2/9 for PTA, 5/13, 8/13, and 5/13 for bare metal stents, and 1/4, 4/4, and 0/4 for open bypass. For all patients, freedom from recurrent symptoms, restenosis, and reinterventions were 70% ± 10%, 60% ± 10% and 50% ±10% at 2 years. For patients treated by rER, secondary patency rates were 72 ± 12 at the same interval. CONCLUSIONS Nearly 40% of patients developed mesenteric artery in-stent restenosis, of which half required reintervention because of symptom recurrence or progression to an asymptomatic preocclusive lesion. Mesenteric reinterventions were associated with low mortality (3%), high complication rate (27%), and excellent symptom improvement (92%).

Ectopic varices in the gastrointestinal tract: short- and long-term outcomes of percutaneous therapy.

To evaluate the results of percutaneous management of ectopic varices, a retrospective review was carried out of 14 patients (9 men, 5 women; mean age 58 years) who between 1992 and 2001 underwent interventional radiological techniques for management of bleeding ectopic varices. A history of prior abdominal surgery was present in 12 of 14 patients. The interval between the surgery and percutaneous intervention ranged from 2 to 38 years. Transhepatic portal venography confirmed ectopic varices to be the source of portal hypertension-related gastrointestinal bleeding. Embolization of the ectopic varices was performed by a transhepatic approach with coil embolization of the veins draining into the ectopic varices. Transjugular intrahepatic portosystemic shunt (TIPS) was performed in the standard fashion. Eighteen procedures (12 primary coil embolizations, 1 primary TIPS, 2 re-embolizations, 3 secondary TIPS) were performed in 13 patients. One patient was not a candidate for percutaneous treatment. All interventions but one (re-embolization) were technically successful. In 2 of 18 interventions, re-bleeding occurred within 72 hr (both embolization patients). Recurrent bleeding (23 days to 27 months after initial intervention) was identified in 9 procedures (8 coil embolizations, 1 TIPS due to biliary fistula). One patient had TIPS revision because of ultrasound surveillance findings. New encephalopathy developed in 2 of 4 TIPS patients. Percutaneous coil embolization is a simple and safe treatment for bleeding ectopic varices; however, recurrent bleeding is frequent and reintervention often required. TIPS can offer good control of bleeding at the expense of a more complex procedure and associated risk of encephalopathy.

Prospective, nonrandomized study to evaluate endovascular repair of pararenal and thoracoabdominal aortic aneurysms using fenestrated-branched endografts based on supraceliac sealing zones

Purpose: To investigate outcomes of manufactured fenestrated and branched endovascular aortic repair (F‐BEVAR) endografts based on supraceliac sealing zones to treat pararenal aortic aneurysms and thoracoabdominal aortic aneurysms (TAAAs). Methods: A total of 127 patients (91 male; mean age, 75 ± 10 years old) were enrolled in a prospective, nonrandomized single‐center study using manufactured F‐BEVAR (November 2013‐March 2015). Stent design was based on supraceliac sealing zone in all patients with ≥ four vessels in 111 (89%). Follow‐up included clinical examination, laboratory studies, duplex ultrasound, and computed tomography imaging at discharge, 1 month, 6 months, and yearly. End points adjudicated by independent clinical event committee included mortality, major adverse events (any mortality, myocardial infarction, stroke, paraplegia, acute kidney injury, respiratory failure, bowel ischemia, blood loss >1 L), freedom from reintervention, and branch‐related instability (occlusion, stenosis, endoleak or disconnection requiring reintervention), target vessel patency, sac aneurysm enlargement, and aneurysm rupture. Results: There were 47 pararenal, 42 type IV, and 38 type I‐III TAAAs with mean diameter of 59 ± 17 mm. A total of 496 renal‐mesenteric arteries were incorporated by 352 fenestrations, 125 directional branches, and 19 celiac scallops, with a mean of 3.9 ± 0.5 vessels per patient. Technical success of target vessel incorporation was 99.6% (n = 493/496). There were no 30‐day or in‐hospital deaths, dialysis, ruptures or conversions to open surgical repair. Major adverse events occurred in 27 patients (21%). Paraplegia occurred in two patients (one type IV, one type II TAAAs). Follow‐up was >30 days in all patients, >6 months in 79, and >12 months in 34. No patients were lost to follow‐up. After a mean follow‐up of 9.2 ± 7 months, 23 patients (18%) had reinterventions (15 aortic, 8 nonaortic), 4 renal artery stents were occluded, five patients had type Ia or III endoleaks, and none had aneurysm sac enlargement. Primary and secondary target vessel patency was 96% ± 1% and 98% ± 0.7% at 1 year. Freedom from any branch instability and any reintervention was 93% ± 2% and 93% ± 2% at 1 year, respectively. Patient survival was 96% ± 2% at 1 year for the entire cohort. Conclusions: Endovascular repair of pararenal aortic aneurysms and TAAAs, using manufactured F‐BEVAR with supraceliac sealing zones, is safe and efficacious. Long‐term follow‐up is needed to assess the impact of four‐vessel designs on device‐related complications and progression of aortic disease.

Differences in anatomy and outcomes in patients treated with open mesenteric revascularization before and after the endovascular era.

OBJECTIVE To compare the clinical characteristics, anatomy, and outcomes of patients treated with open mesenteric revascularization (OR) for chronic mesenteric ischemia (CMI) before and after the preferential use of endovascular revascularization (ER). METHODS We reviewed a prospective database of 257 patients treated for CMI with OR or ER from 1998 to 2009. Treatment trends were analyzed to identify changes in practice paradigm. Prior to 2002, OR was used in 58 of 81 patients (72%). Since 2002, ER surpassed OR as the most common treatment option; OR was indicated in 58 of 176 patients (33%) who either failed ER or had unfavorable lesions for stent placement. We analyzed differences in clinical data, anatomical characteristics, and outcomes in 116 patients treated with OR before (Pre-Endo, n = 58) and after 2002 (Post-Endo, n = 58). Anatomical characteristics were determined by a blinded investigator using conventional angiography, magnetic resonance angiography, and computed tomography angiography with centerline of flow measurements. RESULTS Both groups had similar demographics, risk factors, and clinical presentation, with the exception of higher (P < .05) rates of hypertension, hyperlipidemia, cardiac interventions, dysrhythmias, and higher comorbidity scores in the Post-Endo group. This group also had more extensive mesenteric artery disease, including higher incidence of three-vessel involvement (76% vs 57%; P = .048) and superior mesenteric artery (SMA) occlusion (67% vs 41%;P = .005). There were no differences (P > .05) in the number of vessels revascularized (1.8 ± 0.4 vs 1.7 ± 0.5) and in graft configuration (antegrade, 91% vs 78%; retrograde, 9% vs 22%; two-vessel, 69% vs 81%) in the Pre- and Post-Endo groups, respectively. There were no differences in operative mortality (1.7% vs 3.4%), morbidity (43% vs 53%), length of stay (12 ± 1 vs 12 ± 1 days), and immediate symptom improvement (88% vs 86%) in the Pre- and Post-Endo groups, respectively. Mean follow-up was 57 ± 6 months for patients treated before 2002 and 29 ± 6 months for those treated after 2002 (P = .0001). At 5 years, primary and secondary patency rates and recurrence-free survival were 82%, 86%, and 84% in the Pre-Endo and 81%, 82%, and 76% in the Post-Endo groups (P > .05). CONCLUSION OR has been used in approximately one-third of patients treated for CMI since 2002. Despite more comorbidities and more extensive mesenteric artery disease in patients now treated with OR, outcomes have not changed compared with those operated prior to the preferential use of mesenteric stents before 2002.

Posterior Nutcracker Syndrome

Renal vein compression syndromes are rare causes of hematuria and can be divided into anterior and posterior nutcracker syndrome. When the left renal vein is compressed between the aorta and the superior mesenteric artery it causes anterior nutcracker syndrome. The posterior nutcracker syndrome is very rare and is considered when the left renal vein is compressed between the aorta and vertebral column. Symptoms of nutcracker syndromes may include intermittent left flank pain associated with hematuria, proteinuria, and sometimes with symptoms of pelvic congestion. Diagnosis is often difficult and plan for treatment is always challenging and requires careful evaluation of the patient’s history and workup findings. We present a rare case report of a posterior nutcracker syndrome diagnosed in a young lady with long-standing symptoms that required surgical intervention.

High temporal and spatial resolution 3D time-resolved contrast-enhanced magnetic resonance angiography of the hands and feet

Methods are described for generating 3D time‐resolved contrast‐enhanced magnetic resonance (MR) angiograms of the hands and feet. Given targeted spatial resolution and frame times, it is shown that acceleration of about one order of magnitude or more is necessary. This is obtained by a combination of 2D sensitivity encoding (SENSE) and homodyne (HD) acceleration methods. Image update times from 3.4–6.8 seconds are provided in conjunction with view sharing. Modular receiver coil arrays are described which can be designed to the targeted vascular region. Images representative of the technique are generated in the vasculature of the hands and feet in volunteers and in patient studies. J. Magn. Reson. Imaging 2011;.

Intraoperative duplex ultrasound of visceral revascularizations: optimizing technical success and outcome

PURPOSE The purpose of this study was to evaluate the use of intraoperative duplex ultrasound scanning (IOUS) during visceral revascularizations and correlate its results with clinical outcome. METHODS We studied 68 patients (15 men and 53 women, mean age 66.5 years, range 27-86 years) who underwent visceral revascularization with concomitant IOUS examination of 120 visceral arteries (52 celiac, 60 superior mesenteric, and 8 inferior mesenteric arteries) from 1992 to 2002. Patients were divided into two groups on the basis of ultrasound findings: normal and abnormal IOUS. The incidence of early and late graft-related complications (thrombosis, restenosis, recurrent symptoms, reintervention) and graft-related death was compared in both groups. RESULTS One-hundred and two (85%) arteries had normal IOUS. Eight (6.6%) arteries had minor defects, including small kinks (4), mild residual stenoses (3), and small intimal flap (1). Ten (8.4%) arteries had major defects, consisting of hemodynamically significant residual stenoses (4), thrombus (2), kinks (2), bidirectional flow (1), and intimal flap (1). Major defects were successfully revised in all except three cases: two persistent mild stenoses and one bidirectional flow. Patients with abnormal IOUS at the end of the operation had increased incidence of graft-related complications and/or death (55.5% vs 7.8%; P =.004), early graft thrombosis (14.2% vs 1.0; P =.04), reintervention (21.4% vs 3.2%; P =.03), and graft-related death (33.3% vs 1.9%; P =.02), compared with patients with normal IOUS. CONCLUSION This study supports the routine use of IOUS during visceral revascularizations to optimize technical success and outcome. Persistent ultrasound scanning abnormalities are associated with risk of early graft failure, reintervention, and death. Patients with normal ultrasound scans can expect excellent results.

Prospective Comparison of Cartesian Acquisition with Projection-like Reconstruction Magnetic Resonance Angiography with Computed Tomography Angiography for Evaluation of below-the-Knee Runoff

PURPOSE To compare prospectively the assessment of stenosis and radiologist confidence in the evaluation of below-the-knee lower extremity runoff vessels between computed tomography (CT) angiography and contrast-enhanced magnetic resonance (MR) angiography in a cohort of 19 clinical patients. MATERIALS AND METHODS The study was compliant with the Health Insurance Portability and Accountability Act of 1996 and approved by the institutional review board. Imaging was performed in 19 consecutive patients with known or suspected peripheral arterial disease; both CT angiography and a more recently developed MR angiography technique were performed within 24 hours of each other and before any therapeutic intervention. Resulting images were randomized and interpreted in blinded fashion by four board-certified radiologists with expertise in CT angiography and MR angiography. Vasculature of the lower leg was apportioned into 22 segments, 11 for each leg. For each segment, degree of stenosis and confidence of diagnosis were determined using a 3-point scale. Differences between CT angiography and MR angiography were assessed for significance using pooled histograms that were analyzed using the Wilcoxon signed rank test. RESULTS For assessment of stenosis, there was no difference in CT angiography compared with MR angiography for 20 of 22 segments. For confidence of diagnosis, assessment of popliteal arteries was superior on CT angiography compared with MR angiography (P<.05). Confidence in assessment of both tibioperoneal trunks and the left proximal anterior tibial artery was not significantly different between CT angiography and MR angiography. Confidence in assessment of all other 17 segments was superior with MR angiography compared with CT angiography (P<.02). CONCLUSIONS MR angiography using the method described here is a promising technique for evaluating lower extremity arterial runoff. MR angiography had an overall superior performance in radiologist confidence compared with CT angiography for imaging runoff vessels below the knee.

Endovascular aortic aneurysm repair in patients with narrow aortas using bifurcated stent grafts is safe and effective

OBJECTIVE Narrowing of the distal aortic bifurcation can result in stent graft compression or arterial disruption during endovascular aortic aneurysm repair (EVAR). The aim of our study was to evaluate results of EVAR in patients with narrow distal aortic bifurcations. METHODS We reviewed the clinical data of 1070 patients who underwent EVAR between 2000 and 2011. Digital computed tomography angiograms were analyzed using centerline of flow measurements to determine aortic diameters. Patients with a distal aortic bifurcation diameter <18 mm were included in the study. End points were technical success, aortic disruption with retroperitoneal hemorrhage, stent graft complications (endoleaks, migration, sac enlargement, stenosis), reintervention, and iliac limb patency. RESULTS EVAR was used to treat 112 patients (84 men and 28 women; mean age, 75 years) with aortic bifurcation <18 mm, including 34 (30%) who had diameter of <14 mm. Mean outer and inner aortic bifurcation diameter was 16 ± 3 and 14 ± 2 mm, respectively. Bifurcated stent grafts were used in 106 patients (95%). Six patients (5%) had planned aortouniiliac converters with femoral crossover graft. The aortic bifurcation was dilated after placement of bifurcated stent grafts using kissing balloon angioplasty in 80 patients (75%). All bifurcated stent grafts were successfully implanted, with no conversions to open repair or aortouniiliac converters. There were two early deaths (1.8%), and 12 patients (11%) developed early complications. No aortic disruptions or retroperitoneal hematomas occurred in the group treated with bifurcated grafts. After a median follow-up of 35 months, 11 patients (11%) treated by bifurcated stent grafts required reintervention to treat endoleak (n = 6) or iliac limb stenosis/occlusion (n = 5). One patient (17%) treated by aortouniiliac converter developed critical stenosis of an aortouniiliac graft limb, which was successfully treated with balloon angioplasty 29 months after the initial surgery. At 1 and 5 years, freedom from reintervention was 91% ± 3% and 84% ± 4%, respectively, for bifurcated stent grafts and 100% and 83% ± 10%, respectively, for aortouniiliac converters. Primary and secondary iliac limb patency was 98% ± 3% and 100%, respectively, for bifurcated stent grafts and 83% ± 10% and 100%, respectively, for aortouniiliac converters. CONCLUSIONS EVAR with bifurcated stent grafts is safe and effective in patients with a narrow distal aortic diameter, even when the aortic bifurcation measures <14 mm. Adjunctive balloon dilatation did not result in any bleeding complications from aortic disruption, and limb patency was excellent. Aortouniiliac converters are rarely needed for this indication.