Tina R. Desai

Angiographic access site complications in the era of arterial closure devices.

Coronary and peripheral angiography is associated with a low but significant risk of access site complications. While percutaneous devices have been shown to permit more rapid puncture site closure, previous reports have suggested the incidence and severity of complications associated with these devices are greater than with manual compression. This study compares access site complications with and without closure devices in the current era. The authors conducted a retrospective review of patients with access site complications after coronary or peripheral angiography between 1998 and 2000. Forty-five complications requiring vascular surgical consultation were identified in the 4,800 procedures performed during this time period. Fourteen complications occurred in 1,536 procedures (0.9%) using suture-mediated or collagen devices and 31 occurred in 3,264 procedures without devices (0.9%). The types of procedures and catheter sizes (mean 7 Fr) used were not different in the 2 groups. Other than complications involving a retained device, there was no difference between device and manual compression with respect to incidence or types of complication, requirement for operation, type of operation, or outcome. Access site complications identified included pseudoaneurysm (n = 22; 49%), bleeding or hematoma (n = 8; 18%), arteriovenous fistula (n =5; 11%), arterial thrombosis (n = 4; 9%), infection (n = 4; 9%), and retained device (n = 2; 4%). Twenty-four patients (71% vs 45%; p=NS) required operative intervention including pseudoaneurysm repair, hematoma drainage, and thrombectomy. Eleven patients (26%) underwent successful ultrasound-guided pseudoaneurysm compression and 9 patients (21%) required no intervention. These data demonstrate that closure devices facilitate arterial puncture site repair without an increase in access site complications. These devices can be safely utilized when rapid hemostasis is desired after coronary or peripheral angiography.

Reappraisal of velocity criteria for carotid bulb/internal carotid artery stenosis utilizing high-resolution B-mode ultrasound validated with computed tomography angiography

OBJECTIVE Reliability of the most commonly used duplex ultrasound (DUS) velocity thresholds for internal carotid artery (ICA) stenosis has been questioned since these thresholds were developed using less precise methods to grade stenosis severity based on angiography. In this study, maximum percent diameter carotid bulb ICA stenosis (European Carotid Surgery Trial [ECST] method) was objectively measured using high resolution B-mode DUS validated with computed tomography angiography (CTA) and used to determine optimum velocity thresholds for > or =50% and > or =80% bulb internal carotid artery stenosis (ICA). METHODS B-mode DUS and CTA images of 74 bulb ICA stenoses were compared to validate accuracy of the DUS measurements. In 337 mild, moderate, and severe bulb ICA stenoses (n = 232 patients), the minimal residual lumen and the maximum outer bulb/proximal ICA diameter were determined on longitudinal and transverse images. This in contrast to the North American Symptomatic Carotid Endarterectomy Trial (NASCET) method using normal distal ICA lumen diameter as the denominator. Severe calcified carotid segments and patients with contralateral occlusion were excluded. In each study, the highest peak systolic (PSV) and end-diastolic (EDV) velocities as well as ICA/common carotid artery (CCA) ratio were recorded. Using receiver operating characteristic (ROC) analysis, the optimum threshold for each hemodynamic parameter was determined to predict > or =50% (n = 281) and > or =80% (n = 62) bulb ICA stenosis. RESULTS Patients mean age was 74 +/- 8 years; 49% females. Clinical risk factors for atherosclerosis included coronary artery disease (40%), diabetes mellitus (32%), hypertension (70%), smoking (34%), and hypercholesterolemia (49%). Thirty-three percent of carotid lesions (n = 110) presented with ischemic cerebrovascular symptoms and 67% (n = 227) were asymptomatic. There was an excellent agreement between B-mode DUS and CTA (r = 0.9, P = .002). The inter/intraobserver agreement (kappa) for B-mode imaging measurements were 0.8 and 0.9, respectively, and for CTA measurements 0.8 and 0.9, respectively. When both PSV of > or =155 cm/s and ICA/CCA ratio of > or =2 were combined for the detection of > or =50% bulb ICA stenosis, a positive predictive value (PPV) of 97% and an accuracy of 82% were obtained. For a > or =80% bulb ICA stenosis, an EDV of > or =140 cm/s, a PSV of > or =370 cm/s and an ICA/CCA ratio of > or =6 had acceptable probability values. CONCLUSION Compared with established velocity thresholds commonly applied in practice, a substantially higher PSV (155 vs 125 cm/s) was more accurate for detecting > or =50% bulb/ICA stenosis. In combination, a PSV of > or =155 cm/s and an ICA/CCA ratio of > or =2 have excellent predictive value for this stenosis category. For > or =80% bulb ICA stenosis (NASCET 60% stenosis), an EDV of 140 cm/s, a PSV of > or =370 cm/s, and an ICA/CCA ratio of > or =6 are equally reliable and do not indicate any major change from the established criteria. Current DUS > or =50% bulb ICA stenosis criteria appear to overestimate carotid bifurcation disease and may predispose patients with asymptomatic carotid disease to untoward costly diagnostic imaging and intervention.

The Use of Arterial Closure Devices for Incidental Arterial Injury

Incidental arterial injury is one of the main mechanical complications associated with central venous catheter placement. These injuries can result in significant morbidity and mortality. The use of arterial closure devices to repair these injuries offers a less invasive alternative than open repair and a safer approach than manual compression. We present 3 cases of critically ill patients treated with arterial closure devices when attempted central venous catheterization failed and inadvertent arterial cannulation occurred. A brief review of the various closure devices and there indications is discussed.

Nonenhanced arterial spin labeled carotid MR angiography using three-dimensional radial balanced steady-state free precession imaging

To optimize and preliminarily evaluate a three‐dimensional (3D) radial balanced steady‐state free precession (bSSFP) arterial spin labeled (ASL) sequence for nonenhanced MR angiography (MRA) of the extracranial carotid arteries.

Routine early postoperative duplex scanning is unnecessary following uncomplicated carotid endarterectomy.

Although early postoperative duplex scanning has become routine after carotid endarterectomy (CEA), it is unclear whether the results of these scans alter clinical management. The purpose of this study was to critically examine the usefulness of early postoperative duplex scans in evaluating the ipsilateral carotid artery (for technical perfection) as well as the contralateral carotid artery (for potential velocity changes after improvements in ipsilateral flow). Consecutive patients undergoing CEA between January 1995 and June 1999 in a tertiary hospital setting were studied. Patients underwent early postoperative duplex scanning according to the discretion of the operating surgeon and the availability of the patient. In 212 patients 236 CEAs were performed with selective use of patch closure (49%), intraluminal shunting (19%), and intraoperative completion imaging studies (1 4%). Neurologic complications included 3 transient ischemic attacks (TIAs) (1.3%), 3 nondisabling strokes (1.3%), and 3 disabling strokes (1.3%). There was 1 30-day death from myocardial infarction. Patients were followed up for a median of 18 months (range 0-72 months). Sixty-five percent of patients undergoing uncomplicated CEA (147/227) underwent early duplex surveillance within 6 months of operation. Unsuspected sonographic abnormalities were discovered in 8 patients (5%), including 7 cases of mild internal carotid artery (ICA) stenosis (> 50% by velocity criteria) and 1 case of common carotid artery (CCA) stenosis (intimal flap). None of the patients with ICA stenosis developed symptoms or required operation at any time. The CCA intimal flap was electively repaired without complication. Postoperative changes in velocity in the contralateral ICA were found in 8/48 (17%) cases. There were 3 cases of increased velocity, upgrading 1 from 0-49% to 50-79% stenosis and upgrading 2 from 50-79% to 80-99% stenosis. The latter patients both underwent uneventful contralateral CEA. There were 6 cases of decreased velocity, resulting in downgrading of stenoses from 50-79% to 0-49% (n = 5) or from 80-99% to 50-79% (n = 1). Only the latter patient underwent contralateral CEA; the remainder have been followed up without intervention. Early scanning appeared to offer no clinical benefit; survival and neurologic outcome were the same in the 135 patients scanned within the first 6 months as in the 68 patients whose first postoperative scan occurred later (4-year neurologic event rate 0% in both groups; patient survival with early duplex 98 ± 1.5%, without early duplex 96 ±2.6%; p = NS). Early ipsilateral duplex abnormalities following CEA are infrequent in asymptomatic patients and, even if found, rarely alter management. Patients with bilateral stenosis being considered for contralateral CEA should undergo repeat duplex scanning after the first operation, because of the significant rate (19%) of contralateral velocity changes induced by ipsilateral CEA.

Is Atherectomy the Best First-Line Therapy for Limb Salvage in Patients With Critical Limb Ischemia?:

Objective: To determine the efficacy of atherectomy for limb salvage compared with open bypass in patients with critical limb ischemia. Methods: Ninety-nine consecutive bypass and atherectomy procedures performed for critical limb ischemia between January 2003 and October 2006 were reviewed. Results: A total of 99 cases involving TASC C (n = 43, 44%) and D (n = 56, 56%) lesions were treated with surgical bypass in 59 patients and atherectomy in 33 patients. Bypass and atherectomy achieved similar 1-year primary patency (64% vs 63%; P = .2). However, the 1-year limb salvage rate was greater in the bypass group (87% vs 69%; P = .004). In the tissue loss subgroup, there was a greater limb salvage rate for bypass patients versus atherectomy (79% vs 60%; P = .04). Conclusions: Patients with critical limb ischemia may do better with open bypass compared with atherectomy as first-line therapy for limb salvage.

Decrease in mucosal alkaline phosphatase: A potential marker of intestinal reperfusion injury ☆ ☆☆ ★

Intestinal ischemia necessitates rapid re-establishment of blood flow to prevent irreversible anoxic tissue damage. However, reperfusion results in additional injury as a consequence of the generation of oxygen free radicals. To date, no clear-cut marker to differentiate between ischemia versus reperfusion injury is available. In this regard, previous studies from our laboratory utilizing a rat in vitro lipid peroxidation model demonstrated that the generation of free radicals resulted in the inactivation of only the intestinal brush border alkaline phosphatase enzyme, with no effect on other membrane-bound digestive enzymes. Current studies were designed to assess the possibility of alkaline phosphatase being a specific marker of the reperfusion injury in canine and human ex vivo ischemia/reperfusion models. Small bowels harvested from canines and organ donors were subjected to ischemia followed by reperfusion. Brush border membrane enzymes, alkaline phosphatase, sucrase, maltase, and gamma-glutamyl transpeptidase were assayed in mucosal extracts from intestines with ischemia versus reperfusion. In both experimental models, there was no change in any enzyme activity with warm ischemia alone. In contrast, alkaline phosphatase activity was significantly decreased in both the canine and human reperfusion models, with no change in specific activities of sucrase, maltase, and gamma-glutamyl transpeptidase. Our data indicate that the alkaline phosphatase enzyme activity may represent a potential marker of intestinal reperfusion injury and may permit quantitative assessments of therapeutic interventions in human intestinal reperfusion injury.

Resection of Intracaval Leiomyomatosis Using Abdominal Approach and Venovenous Bypass

BACKGROUND Intravenous leiomyomatosis is the venous involvement of a histologically benign uterine tumor. This uncommon tumor can present contemporaneously with the primary uterine tumor or in a delayed fashion. Tumor extends up the venous system, via the iliac or ovarian veins, and can involve portions or all of the inferior vena cava and can extend into the heart as well. Complete resection of this tumor is the therapeutic goal. Previous reports have described the use of combined thoracic and abdominal approaches, cardiopulmonary bypass, circulatory arrest, and a single report of an entirely abdominal approach to resection without bypass. METHODS AND RESULTS We present a review of the existing literature describing surgical intervention for intravenous leiomyomatosis and describe two cases of tumor extending up the intra-abdominal vena cava. Using venovenous bypass without need for thoracotomy, we were able to resect both tumors with minimal blood loss and no hemodynamic instability. CONCLUSIONS We suggest that venovenous bypass is an excellent tool in resection of these tumors and should be considered for many cases in lieu of full cardiopulmonary bypass or circulatory arrest.

Bypass Procedures for Mesenteric Ischemia

Acute or chronic mesenteric ischemic syndromes result from interruption of mesenteric blood flow. Specific symptoms depend on the nature, degree, and duration of blood flow interruption as well as individual differences in specific mesenteric anatomy and collateral development. Typically, elderly patients with multiple atherosclerotic comorbidities are more frequently affected by acute syndromes; patients with chronic mesenteric ischemia symptoms are more frequently younger (mean age of 58) and female (60%) (Moawad et al. 1997). Both groups of patients manifest a high incidence of smoking, hypertension, coronary artery disease and cerebrovascular disease.

Transaortic Septectomy as Treatment for Chronic Mesenteric Ischemia After Aortic Dissection: A Case Report

Visceral ischemia can present as an acute or chronic complication of aortic dissection, which is associated with high morbidity and mortality rates, up to 50-87%. Furthermore, the optimal management strategy for this problem is unclear. The authors present a case of chronic mesenteric ischemia complicating a Stanford type A aortic dissection which was treated with transaortic septectomy. A 56-year-old man presented with chronic abdominal pain and a 30-pound weight loss after operative repair of an ascending aortic dissection with replacement of his aortic valve and ascending aorta. Two prior attempts at balloon fenestration of his aortic dissection in the area of his mesenteric vessels had failed to improve his symptoms. Angiography, computed tomography scan, and duplex evaluation of the aorta revealed a 5 cm suprarenal aorta with the false lumen occupying the majority of the diameter. The origins of the mesenteric vessels from the true lumen were compressed by the septum. The patient underwent a septectomy and aortoplasty of his suprarenal aorta via a retroperitoneal approach. A postoperative duplex scan showed widely patent origins of the celiac, superior mesenteric, and renal arteries. The patients postprandial pain completely resolved before hospital discharge. Aortoplasty and septectomy presents a newly described treatment of complications of aortic dissection and has been utilized in the acute and chronic settings. It allows successful treatment of aneurysmal and occlusive complications in the dissected aorta. The evaluation and operative treatment of a patient with both these complications is discussed.