Citations

Background and Purpose— Evidence indicates that center volume of cases affects outcomes for both carotid endarterectomy and stenting. We evaluated the effect of enrollment volume by site on complication rates in the Carotid Revascularization Endarterectomy Versus Stenting Trial (CREST). Methods— The primary composite end point was any stroke, myocardial infarction, or death within 30 days or ipsilateral stroke in follow-up. The 477 approved surgeons performed >12 procedures per year with complication rates <3% for asymptomatic patients and <5% for symptomatic patients; 224 interventionists were certified after a rigorous 2 step credentialing process. CREST centers were divided into tertiles based on the number of patients enrolled into the study, with Group 1 sites enrolling <25 patients, Group 2 sites enrolling 25 to 51 patients, and Group 3 sites enrolling >51 patients. Differences in periprocedural event rates for the primary composite end point and its components were compared using logistic regression adjusting for age, sex, and symptomatic status within site-volume level. Results— The safety of carotid angioplasty and stenting and carotid endarterectomy did not vary by site-volume during the periprocedural period as indicated by occurrence of the primary end point ( P =0.54) or by stroke and death ( P =0.87). A trend toward an inverse relationship between center enrollment volume and complications was mitigated by adjustment for known risk factors. Conclusions— Complication rates were low in CREST and were not associated with center enrollment volume. The data are consistent with the value of rigorous training and credentialing in trials evaluating endovascular devices and surgical procedures. Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: NCT00004732.

Phrenic motor neurons are recruited across a range of motor behaviors to generate varying levels of diaphragm muscle (DIAm) force. We hypothesized that DIAm motor units are recruited in a fixed order across a range of motor behaviors of varying force levels, consistent with the Henneman Size Principle. Single motor unit action potentials and compound DIAm EMG activities were recorded in anesthetized, neurally intact rats across different motor behaviors, i.e., eupnea, hypoxia-hypercapnia (10% O 2 and 5% CO 2 ), deep breaths, sustained airway occlusion, and sneezing. Central drive [estimated by root-mean-squared (RMS) EMG value 75 ms after the onset of EMG activity (RMS 75 )], recruitment delay, and onset discharge frequencies were similar during eupnea and hypoxia-hypercapnia. Compared with eupnea, central drive increased (∼25%) during deep breaths, and motor units were recruited ∼12 ms earlier ( P < 0.01). During airway occlusion, central drive was ∼3 times greater, motor units were recruited ∼30 ms earlier ( P < 0.01), and motor unit onset discharge frequencies were significantly higher ( P < 0.01). Recruitment order of motor unit pairs observed during eupnea was maintained for 98%, 87%, and 84% of the same pairs recorded during hypoxia-hypercapnia, deep breaths, and airway occlusion, respectively. Reversals in motor unit recruitment order were observed primarily if motor unit pairs were recruited <20 ms apart. These results are consistent with DIAm motor unit recruitment order being determined primarily by the intrinsic size-dependent electrophysiological properties of phrenic motor neurons.

Surgical treatment has been advocated for ischial tuberosity avulsion fractures in athletes. This article presents the case of an elite rower with a large avulsion fracture involving the entire inferior obturator ring with a novel technique for open reduction using a limited Kocher-Langenbeck approach and percutaneous fixation using posterior column lag screws. The fracture healed anatomically, and at 1 year follow-up the patient had full range of motion, normal gait and had returned to high-level sporting activities.

Coronary arteries have been extensively described and recognized by gross anatomic studies. However, in the clinical setting, the recognition of the conal artery is essential during coronary angiography, as well as certain congenital heart conditions such as tetralogy of Fallot. In order to provide a complete anatomic and physiologic correlation of the actual incidence and distribution of the conal artery we examined 300 formalin fixed hearts with gross dissections and 300 coronary angiograms. The conal artery was identified in all hearts examined and five main patterns were recognized. In Type A (193, 32.1%), the conal artery arose as a branch of the right coronary artery (RCA); in Type B (96, 16%), the conal artery arose from the common coronary ostium with the RCA; in Type C (242, 40.3%), the conal artery took origin from the right aortic sinus as an independent artery; in Type D (48, 8%), multiple conal arteries were present and arose from the RCA as separate branches (32, 66.6%), from a common ostium with the RCA (8, 16.6%) or from the aortic sinus (8, 16.6%); in Type E (22, 3.6%), the conal artery arose as a branch of the right ventricular branch (17, 2.8%) or acute marginal artery (5, 0.8%). The relative prevalence of the five patterns as well as the morphology and the topography of the conal artery varied significantly with the degree of coronary luminal stenosis (as observed during angiography) and also with the degree of hypertrophied ventricular wall (as observed during gross dissections). Clin. Anat. 29:371–379, 2016. © 2014 Wiley Periodicals, Inc.

ObjectivesWe sought to determine neuroimaging patterns, ischemic mechanisms, and functional outcomes of ischemic stroke related to percutaneous coronary intervention (PCI) over a 16‐year period. Background: Stroke is a feared complication of PCI, associated with poor patient outcomes. The majority of strokes that occur after PCI are ischemic rather than hemorrhagic. However, mechanisms of cerebral ischemia in this setting are incompletely understood.MethodsWe performed a retrospective single‐center cohort study of patients with radiologically confirmed ischemic stroke occurring after PCI (PCI‐stroke), between January 1, 1994 and December 31, 2009. Using brain imaging, infarctions were subclassified by radiological pattern and arterial territory as embolic, small subcortical, or hemodynamic. Modified Rankin Scale scores were used to assess functional outcome at 3 and 6 months.ResultsRadiologically confirmed PCI‐stroke was identified in 35 patients. The majority of strokes (91%) revealed an embolic pattern, while the remaining strokes were small subcortical infarctions (9%). Watershed strokes with exclusive borderzone involvement, indicative of a hemodynamic mechanism, were not identified, despite the presence of periprocedural hypotension in 23% of patients. The middle cerebral artery (MCA) territory was affected most frequently (80%), and all patients suffering a complete MCA territorial infarction (14%) died in the hospital. Functional outcome among survivors of PCI‐stroke was typically favorable in those who had single rather than multiple vascular territory involvement.ConclusionsThe vast majority of radiologically confirmed ischemic strokes related to PCI are embolic. MCA territory strokes are most common and uniformly fatal when the entire MCA territory is affected. Functional outcomes in survivors of PCI‐stroke are improved when only a single arterial territory is affected. © 2014 Wiley Periodicals, Inc.