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Background-Endoleaks after stent-graft repair of aortic dissections are poorly understood but seem substantially different from those seen after aneurysm repair. We studied anatomic and clinical factors associated with endoleaks in patients who underwent stent-graft repair of complicated type B aortic dissections. Methods and Results-From 2000 to 2007, 37 patients underwent stent-graft repair of acute (Յ14 days; nϭ23), subacute (15 to 90 days; nϭ10) or chronic (Ͼ90 days; nϭ4) complicated type B aortic dissections using the Gore Thoracic Excluder (nϭ17) or TAG stent-grafts (nϭ20) under an investigator-sponsored protocol. Endoleaks were classified as imperfect proximal seal, flow through fenestrations or branches, or complex (both). Variables studied included coverage of the left subclavian artery, aortic curvature, completeness of proximal apposition, dissection chronicity, and device used. Endoleaks were found during follow-up (mean, 22 months) in 59% of patients, and they were associated with coverage of the left subclavian artery (complex, PϽ0.001), small radius of curvature (type 1 and complex, Pϭ0.05), and greatest length of unapposed proximal stent graft (complex, PϽ0.0001). During follow-up, 10 endoleaks resolved spontaneously, 6 required reintervention for false lumen dilatation, and 2 were stable without clinical consequences. Conclusions-Endoleaks are common after stent-graft repair of aortic dissection and may lead to false lumen enlargement necessitating reintervention. Anatomic complexities such as acute aortic curvature and covered side branches were associated with endoleaks, illustrating the need for dissection-specific device development.

For patients undergoing cardiac surgery with a cardiopulmonary bypass time of greater than 120 minutes, a single dose of cefazolin before skin incision with redosing at wound closure does not provide targeted antimicrobial cefazolin plasma levels during the entire surgical procedure. Patients undergoing profound hypothermic circulatory arrest are better protected, but the described protocol of prophylaxis is not optimal.

Electroconvulsive therapy (ECT) has an important role in the treatment of patients with severe depression or schizophrenia. ECT results in an acute cardiovascular response, characterized by tachycardia, hypertension and increase in cerebral artery blood flow velocity (V mca) [1]. For patients at risk of cardiovascular complications, b-adrenergic blocking agents are often administered to prevent or minimize the increase in blood pressure (BP) and heart rate (HR). The aim of this study was to evaluate the effects of two different b-blockers, esmolol and labetalol, on changes in V mca during ECT using transcranial Doppler (TCD). In a prospective, randomized study, 37 patients undergoing ECT were evaluated. The study was approved by the Stanford Institutional Review Board, and written informed consent was obtained. Anaesthesia was induced with etomidate (0.25 mg kg 21) and succinylcholine (1 mg kg 21). Monitoring consisted of electrocardiogram, BP (non-invasive) and pulse oximetry. In addition, V mca (Neuroguard, MedaSonics, Fremont, CA, USA) of the left middle cerebral artery was measured, using a 2 MHz ultrasonic wave. Patients without pre-existing hypertension (mean arterial pressure (MAP) , 85 mmHg) received no b-blockers (Group N 5 12 patients). Patients with pre-existing hypertension (MAP. 85 mmHg) were, at random, pre-treated with either esmolol (Group E 5 13 patients) or labetalol (Group L 5 12 patients) intravenously to lower MAP to ,85 mmHg. The TCD technician was blinded for the treatment compounds. After induction of anaesthesia, all patients were manually hyperventilated with 100% O 2 for 30 s. ECT was applied when nerve stimulation of the ulnar and radial nerves showed absent twitches, and the patellar reflex was negative. All patients underwent bilateral ECT. V mca , HR and MAP were measured just before induction of anaesthesia (baseline), and at 0.5, 5, 10 and 30 min post-ECT. Data were analysed by one-way analysis of variance on ranks. Dunn's method was used for