Venkat Kalapatapu

Techniques for managing complications of arterial closure devices.

According to data reported by the American Heart Association, more than 5 million diagnostic and therapeutic catheterizations are performed each year in the United States. The number of catheterizations has tripled since 1979. It has been estimated that complications related to the access site result in more than 75,000 surgical procedures annually. Thus, improved management of the access site itself is essential to achieve the greater goals of improved care and reduced cost. Manual compression directly over the site of arterial puncture usually results in adequate hemostasis but has several significant drawbacks. Manual compression is uncomfortable for the patient, is fatiguing and time-consuming for staff, and necessitates several hours of costly in-hospital observation. In addition, it may be ineffective in achieving hemostasis, especially in the setting of systemic anticoagulation or following the use of large-bore devices. Based on the perceived need for an improved method of managing the arterial access site following catheterization, various vascular sealing devices have been developed. There are at least 8 (and the number is increasing) hemostatic vascular closure devices that are currently approved by the FDA for access site closure after femoral arterial catheterization. The chief advantage attributed to vascular sealing devices is accelerated access site hemostasis, even in the setting of anticoagulation, leading to earlier ambulation and hospital discharge following arterial catheterization. The most important drawbacks related to vascular sealing devices include the cost of the devices and the possibility of increased access site complications. Despite the paucity of properly designed studies supporting their use, it is estimated that over one million vascular sealing devices are used annually in the United States, a number that has increased dramatically in the past 5 years.In this review, we present a brief description of the design and function of the most widely used devices, describe the most common mechanisms of failure, and recommend strategies for management of access site complications including hemorrhage, arterial obstruction, and infection.

Definitive Test to Diagnose Median Arcuate Ligament Syndrome: Injection of Vasodilator During Angiography

The diagnosis of median arcuate ligament (MAL) syndrome and its correlation with symptoms has been controversial since the disease entity was described. The authors describe a technique that will identify patients who will benefit from intervention. Eight patients with isolated celiac artery compression from MAL were identified by the authors. Their technique involved selective cannulation of the superior mesenteric artery (SMA) and injection of a vasodilator during angiography. Symptom reproduction and loss of collateral filling of the celiac territory represented a positive test: 4 of the 8 patients had a positive test and underwent successful surgical treatment of the condition; 3 of them remained asymptomatic at follow-up; 1 patient continues to have mild abdominal discomfort. Of the 4 patients with a negative test, 2 were found to have other conditions causing their symptoms. Vasodilator injection into the SMA is a useful diagnostic test to identify patients with symptomatic MAL syndrome.

Percutaneous isolated limb perfusion with thrombolytics for severe limb ischemia.

Patients with severe tibioperoneal disease are poor candidates for a distal bypass. Absence of a distal target, lack of conduit, or multiple medical problems can make these patients a prohibitive risk for revascularization. Acute on chronic ischemia in this group poses a greater challenge. Thrombolytic therapy for acute ischemia can be prolonged and carries a significant risk of bleeding if continued beyond 24 hours. However, if the ischemic limbs can be isolated from the systemic circulation, a higher dose of the lytic agent can be given with lower risk. These are the initial results of a series of 10 patients who underwent percutaneous isolated limb perfusion with a high dose of thrombolytics for severe ischemia. Ten patients (lower extremity 8 and upper extremity 2) presented with severe limb-threatening ischemia. Mean ankle/brachial index (ABI) was 0.15 for the lower extremity, and there were no recordable digital pressures in patients with upper extremity ischemia. No distal target was visible on the initial arteriogram. These patients were then taken to the operating room, and under anesthesia, catheters were placed in an antegrade fashion via femoral approach in the popliteal artery and vein percutaneously. For upper extremity, the catheters were placed in the brachial artery and vein. A proximal tourniquet was then applied. This isolated the limb from the systemic circulation. Heparinized saline was infused through the arterial catheter while the venous catheter was left open. A closed loop or an isolated limb perfusion was confirmed when effluent became clear coming out of the venous port. A high dose of thrombolytic agent (urokinase 500,000 to 1,000,000 U) was infused into the isolated limb via the arterial catheter and drained out of the venous catheter. After 45 minutes, arterial flow was reestablished. In 4 patients, Reopro ® was used in addition to thrombolytics. Postprocedure angiograms showed minimal changes, but patients exhibited marked clinical improvement. The ABI changed from 0.15 to 0.5 in the lower extremity and near-normal digital pressures in upper extremity ischemia. Limb salvage and symptomatic relief at 6 months was 90%. All patients except one were kept on anticoagulation postoperatively. No bleeding complications were observed from the procedure. Percutaneous isolated limb perfusion brought symptomatic relief to patients presenting with acute on chronic limb ischemia. This can be an alternate option for patients facing amputation with no revascularization options.

Remote Superficial Femoral Artery A Endarterectomy: Early Results for TASC D Lesions in Patients With Severe Ischemia

Endovascular treatment for Transatlantic Inter-Society Consensus (TASC) D lesions of the superficial femoral artery has been disappointing. This has been attributed to a bulking atheromatous plaque. Debulking the superficial femoral artery allows for a larger lumen, whereas covering the lumen with an endograft provides in-line flow. We evaluated the intermediate results of remote superficial femoral artery endarterectomy with covered endograft placement in 18 patients. Patient demographic, vascular laboratory, and preoperative data were gathered retrospectively. The procedure was technically successful in all the patients. The mean age was 62.2 ± 9.9 years. Ankle brachial index improved from 0.35 ± 0.1 to 0.86 ± 0.1. The cumulative 12-month primary patency was 42.2%, whereas assisted primary or secondary patency was 70.8%. Five endografts occluded within the 12 months. Two of those patients underwent subsequent femoral-to-below-knee bypass, whereas 2 had major amputations. Remote superficial femoral artery endarterectomy can be reasonably offered if an autogenous conduit is not available for revascularization of the superficial femoral artery.

The effects of Toradol on postoperative intimal hyperplasia in a rat carotid endarterectomy model: laboratory research.

Carotid endarterectomy (CEA) and more recently carotid artery stenting are the treatments of choice for atherosclerotic disease of the extracranial carotid arteries; however, early restenosis caused by neointimal hyperplasia confounds surgical therapy. Oxidative stress has been implicated in the progression of intimal hyperplasia. The authors hypothesized that ketorolac tromethamine (Toradol), a nonsteroidal antiinflammatory drug that is a potent cyclooxygenase inhibitor, would decrease oxidative stress and thereby reduce intimal hyperplasia in a rat CEA model. Twenty-nine male Sprague-Dawley rats underwent CEA and were divided into 3 treatment groups as follows: (1) control (placebo), (2) 7.5 mg/kg Toradol, and (3) 10 mg/kg Toradol. Toradol treatment began 2 days before CEA and continued for 2 weeks. Two weeks after endarterectomy, carotid arteries were fixed, harvested, and examined for platelet activity (platelet reactive units), oxidative stress (malondialdehyde and glutathione), and intimal hyperplasia (measured as percentage of luminal stenosis). Platelet activity, malondialdehyde and glutathione, and intimal hyperplasia were all significantly lowered in both 7.5- and 10-mg/kg doses of Toradol versus control. Toradol given daily beginning 2 days before CEA and ending 2 weeks after the procedure was effective at significantly reducing platelet activity, oxidative stress, and intimal hyperplasia development in the rat without any increase in bleeding. Although the mechanism of action of this reduction is not completely understood, one possible explanation may be through the inhibition of reactive oxygen species production.

Characterization and outcomes of reinterventions in Food and Drug Administration-approved versus trial endovascular aneurysm repair devices

Objective: Published rates of reintervention after endovascular aneurysm repair (EVAR) range from 10% to 30%. We evaluated a single university centers experience with reinterventions in the context of Food and Drug Administration (FDA)‐approved and trial devices. Methods: Retrospective data collection was performed for patients who underwent infrarenal EVAR and required reintervention from 2000 to 2016. Trial devices included those used in FDA feasibility and pivotal trials. Time‐to‐event analysis was performed using Cox regression. Predictors of mortality and explantation were evaluated using logistic regression; survival analysis was performed using Kaplan‐Meier methods. Results: From 2000 to 2016, there were 1835 EVARs performed, and 137 patients (116 men; mean age, 72.2 ± 10.0 years) underwent reintervention with a mean aneurysm size of 5.9 ± 1.2 cm. The median follow‐up was 5 years with an overall survival of 70.1%. The overall reintervention rate was 7.5%. FDA‐approved devices had a reintervention rate of 6.4%, whereas trial devices had a rate of 14.4% (P < .001). For all devices, the most common cause of reintervention was type II endoleak (52.5%), followed by type I endoleak (18.2%), type III endoleak (9.5%), limb kink (7.3%), iliac occlusive disease (5.8%), endotension (1.5%), and other. The overall mean time to first reintervention was 2.3 ± 2.5 years, and univariate Cox regression identified male gender (hazard ratio, 1.91; 95% confidence interval [CI], 1.17–3.10; P = .010) and age at the time of EVAR (hazard ratio, 1.03; 95% CI, 1.01–1.05; P = .006) as risk factors for time to first reintervention. Among patients requiring reintervention, the mean number of reinterventions for trial devices was significantly greater than that for FDA‐approved devices (2.18 vs 1.65; P = .01). Trial devices requiring reintervention had a nearly threefold higher odds for the need for more than two reinterventions (odds ratio, 2.88; 95% CI, 1.12–7.37; P = .034). Trial device, cause of reintervention, and type of reintervention were not predictive of the need for explantation or mortality, but the number of reinterventions was significantly associated with the need for explantation (odds ratio, 1.86; 95% CI, 1.17–2.96; P = .012). EVAR device and the need for explantation did not have an impact on mortality. Conclusions: Despite the rigorous nature of patient enrollment in clinical trials and the development of newer iterations of investigational devices, patients undergoing EVAR with trial devices are more likely to undergo a greater number of reinterventions than with FDA‐approved devices. Although mortality and the need for explantation were not significantly associated with trial devices, the finding of a greater number of reinterventions highlights the need to properly inform patients willing to partake in investigational device trials.

Proximal Forearm Arteriovenous Fistula Creation

Fistula first initiative is the recommended guideline for hemodialysis access. The creation of distal radiocephalic fistula often is not an option; additionally, non-maturation of created fistula leads to use of arm vessels which increases the risk of complications. Proximal forearm fistula even though overlooked may be a viable option with reasonably good outcomes and patency. The case describes proximal radiocephalic fistula (pRCF), ulnar-basilic AVF (UBAVF), and transposed radio-basilic fistula (tRBF) of the forearm and techniques and outcomes.

A case of acute ischemic monomelic neuropathy and review of the literature

Ischemia monomelic neuropathy is rare and underrecognized complication of hemodialysis access (HA), characterized by diffuse multiple mononeuropathies in the absence of significant clinical ischemia. It is important to diagnose this syndrome early because ligation of the HA is the most accepted treatment to prevent or at least halt irreversible neural dysfunction and therefore, chronic pain and disability. Literature describing this fistulae-related pathology is rare, and we attempt to increase its awareness.

Bilateral reperfusion injury after carotid endarterectomy with contralateral carotid occlusion

Cerebral hyperperfusion syndrome represents a clinical spectrum characterized by severe unilateral headache, acute changes in mental status, vomiting, seizures, focal neurologic deficits, and, in its most severe form, intracranial hemorrhage. With the exception of one early case report, reperfusion injury to the brain following carotid endarterectomy has been reported only ipsilateral to the side of surgery. We report the unique case of a patient with symptomatic severe right internal carotid artery stenosis and contralateral carotid occlusion who underwent carotid endarterectomy complicated by cerebral hyperperfusion syndrome and associated bilateral intracranial hemorrhage.

Metastatic endometrial sarcoma with inferior vena caval and cardiac involvement: a combined surgical approach.

Low-grade endometrial stromal sarcoma with intracaval and intracardiac extension represents a complex and often lethal condition. A case of a 40-year-old woman, who underwent hysterectomy for endometrial stromal sarcoma 4 years previously and developed recurrence with intracaval and intracardiac metastases, is presented. Operative management of resection of the intracaval and intracardiac tumor is described. The literature is reviewed in order to highlight the data on diagnosis and management of recurrent endometrial stromal sarcoma with vascular involvement, including the multimodality approach required in treating this disease.