Electrocardiographic Diagnosis of Acute Coronary Occlusion Myocardial Infarction in Ventricular Paced Rhythm Using the Modified Sgarbossa Criteria.

STUDY OBJECTIVE: Ventricular paced rhythm is thought to obscure the electrocardiographic diagnosis of acute coronary occlusion myocardial infarction. Our primary aim was to compare the sensitivity of the modified Sgarbossa criteria (MSC) to that of the original Sgarbossa criteria for the diagnosis of occlusion myocardial infarction in patients with ventricular paced rhythm. METHODS: In this retrospective case-control investigation, we studied adult patients with ventricular paced rhythm and symptoms of acute coronary syndrome who presented in an emergency manner to 16 international cardiac referral centers between January 2008 and January 2018. The occlusion myocardial infarction group was defined angiographically as thrombolysis in myocardial infarction grade 0 to 1 flow or angiographic evidence of coronary thrombosis and peak cardiac troponin I ≥10.0 ng/mL or troponin T ≥1.0 ng/mL. There were 2 control groups: the "non-occlusion myocardial infarction-angio" group consisted of patients who underwent coronary angiography for presumed type I myocardial infarction but did not meet the definition of occlusion myocardial infarction; the "no occlusion myocardial infarction" control group consisted of randomly selected emergency department patients without occlusion myocardial infarction. RESULTS: There were 59 occlusion myocardial infarction, 90 non-occlusion myocardial infarction-angio, and 102 no occlusion myocardial infarction subjects (mean age, 72.0 years; 168 [66.9%] men). For the diagnosis of occlusion myocardial infarction, the MSC were more sensitive than the original Sgarbossa criteria (sensitivity 81% [95% confidence interval [CI] 69 to 90] versus 56% [95% CI 42 to 69]). Adding concordant ST-depression in V4 to V6 to the MSC yielded 86% (95% CI 75 to 94) sensitivity. For the no occlusion myocardial infarction control group of ED patients, additional test characteristics of MSC and original Sgarbossa criteria, respectively, were as follows: specificity 96% (95% CI 90 to 99) versus 97% (95% CI 92 to 99); negative likelihood ratio (LR) 0.19 (95% CI 0.11 to 0.33) versus 0.45 (95% CI 0.34 to 0.65); and positive LR 21 (95% CI 7.9 to 55) versus 19 (95% CI 6.1 to 59). For the non-occlusion myocardial infarction-angio control group, additional test characteristics of MSC and original Sgarbossa criteria, respectively, were as follows: specificity 84% (95% CI 76 to 91) versus 90% (95% CI 82 to 95); negative LR 0.22 (95% CI 0.13 to 0.38) versus 0.49 (95% CI 0.35 to 0.66); and positive LR 5.2 (95% CI 3.2 to 8.6) versus 5.6 (95% CI 2.9 to 11). CONCLUSION: For the diagnosis of occlusion myocardial infarction in the presence of ventricular paced rhythm, the MSC were more sensitive than the original Sgarbossa criteria; specificity was high for both rules. The MSC may contribute to clinical decisionmaking for patients with ventricular paced rhythm.

Salinity tolerance of a rare and endangered unionid mussel, Popenaias popeii (Texas Hornshell) and its implications for conservation and water management.

Unionid mussels are considered sensitive to salinity and there is growing concern in arid and semi-arid regions that declining flows coupled with anthropogenic impacts are amplifying natural salinity levels. In this study, we tested the effects of varying salinity concentrations (3.0, 4.0, 5.0, 6.0, 7.0 and 10.0 ppt NaCl) on survival of adult Popenaias popeii, (Texas Hornshell). This species occurs in the Rio Grande basin of Texas and northern Mexico, an arid to semi-arid stream plagued by salinization, and was recently listed as Endangered under the U.S. Endangered Species Act. We performed 2, 4, and 10-day toxicity tests on individuals from two disjunct populations: Laredo, TX, and the Lower Canyons of the Rio Grande near Big Bend National Park. We found no significant differences in LC50 estimates between populations at 96-hrs or 10-days but significant differences in TUD50s at 5 ppt between populations, which indicates that tolerance does not vary but sensitivity may between these populations. Overlaying LC50 estimates at 10-days for both populations on plots of salinity (ppt) measured over time, we show parts of the Rio Grande periodically approach or exceed 4.0 ppt, indicating these reaches are becoming unsuitable for P. popeii and populations within them at risk.

Effects of Deepwater Horizon Oil on the Movement and Survival of Marsh Periwinkle Snails (Littoraria irrorata).

The Deepwater Horizon (DWH) oil spill resulted in the release of millions of barrels of oil into the Gulf of Mexico, and some marsh shorelines experienced heavy oiling including vegetation laid over under the weight of oil. Periwinkle snails (Littoraria irrorata) are a critical component of these impacted habitats, and population declines following oil spills, including DWH, have been documented. This study determined the effects of oil on marsh periwinkle movement and survivorship following exposure to oil. Snails were placed in chambers containing either unoiled or oiled laid over vegetation to represent a heavily impacted marsh habitat, with unoiled vertical structure at one end. In the first movement assay, snail movement to standing unoiled vegetation was significantly lower in oiled chambers (oil thickness ≈ 1 cm) compared to unoiled chambers, as the majority (∼75%) of snails in oiled habitats never reached standing unoiled vegetation after 72 h. In a second movement assay, there was no snail movement standing unoiled structure in chambers with oil thicknesses of 0.1 and 0.5 cm, while 73% of snails moved in unoiled chambers after 4h. A toxicity assay was then conducted by exposing snails to oil coated Spartina stems in chambers for periods up to 72 h, and mortality was monitored for 7 days post exposure. Snail survival decreased with increasing exposure time, and significant mortality (∼35%) was observed following an oil exposure of less than 24 h. Here, we have shown that oil impeded snail movement to clean habitat over a short distance and resulted in oil-exposure times that decreased survival. Taken together, along with declines documented by others in field surveys, these results suggest that marsh periwinkle snails may have been adversely affected following exposure to DWH oil.

Biomechanical Evaluation of Capsulotomy, Capsulectomy, and Capsular Repair on Hip Rotation.

PURPOSE: To determine the effect of different types of capsulotomies on hip rotational biomechanical characteristics. METHODS: Seven fresh-frozen cadaveric hip specimens were thawed and dissected, leaving the hip capsule and labrum intact. The femur was transected and potted, and each specimen was placed in a custom loading apparatus that allowed for adjustment of flexion, extension, and axial rotation of the femur. Six reflective infrared markers were attached to the specimens to track the motion of the femoral head with respect to the acetabulum in real time, and external rotation was produced by applying a torque of 10 Nm to the hip specimens. Data analysis was performed using the 3-dimensional position of the markers in space. The specimens were tested in neutral flexion and 40° of flexion in the following capsular states: intact, interportal capsulotomy, T-capsulotomy, repaired capsulotomy, and capsulectomy. Paired t tests and analysis of variance were used with an α value of .05 set as significant. RESULTS: With the hip in neutral flexion, there was increased external rotation with a T-capsulotomy (91.1° ± 20.3°, P = .029) and capsulectomy (91.9° ± 19.6°, P = .015) compared with the intact hip (83.2° ± 20.5°). After complete repair of the T-capsulotomy (87.4° ± 20.6°), there was no significant difference in external rotation compared with the intact hip. No significant differences were seen between groups at 40° of hip flexion. CONCLUSIONS: A T-capsulotomy showed significantly increased external rotation versus the intact and interportal capsulotomy states. The repaired T-capsulotomy restored the rotational profile back to the native state. CLINICAL RELEVANCE: Many methods of capsular treatment during hip arthroscopy exist. Capsulotomy and capsulectomy do not restore the external rotation restraint of the hip back to its native state.

Pylephlebitis presenting as spontaneous coronary sinus thrombosis: a case report.

BACKGROUND: Coronary sinus thrombosis is a rare phenomenon. When identified, it most often is a complication of infective endocarditis or procedural intervention. We present an unusual and unreported case of spontaneous coronary sinus thrombosis as embolic sequela of an intra-abdominal infectious process. CASE PRESENTATION: We report a case of a 61-year-old white woman with a history of end-stage renal disease on hemodialysis, paroxysmal atrial fibrillation not on long-term systemic anticoagulation, and history of recurrent diverticulitis that presented with acute onset abdominal pain and nausea. Computed tomography of her abdomen and pelvis with intravenous contrast was negative for acute intra-abdominal pathology, but incidentally identified an oval-shaped filling defect at the ostium of the coronary sinus suspicious for thrombus or mass which was confirmed on subsequent transesophageal echocardiogram. In light of her concomitant transaminitis but otherwise negative workup, the mass was believed to be thromboembolic in nature, originating within the hepatic venous system as a manifestation of recurrent diverticulitis with associated pylephlebitis and ultimately lodging into the coronary sinus. With the newly detected thrombus and history of paroxysmal atrial fibrillation, she was started on warfarin for therapeutic systemic anticoagulation that resolved her clot by 3-month follow up. CONCLUSIONS: Although coronary sinus thrombosis is rare, a high index of suspicion and close scrutiny of the venous system in patients with intra-abdominal infectious processes would prevent delay in management of this potentially serious complication. The discussion of this case highlights the anatomy of the cardiac venous system, the pathophysiology of thrombus formation, and the utility of transesophageal echocardiography in confirming a diagnosis and assessing treatment efficacy.

Infective endocarditis causing mitral valve stenosis - a rare but deadly complication: a case report.

BACKGROUND: Infective endocarditis rarely causes mitral valve stenosis. When present, it has the potential to cause severe hemodynamic decompensation and death. There are only 15 reported cases in the literature of mitral prosthetic valve bacterial endocarditis causing stenosis by obstruction. This case is even more unusual due to the mechanism by which functional mitral stenosis occurred. CASE PRESENTATION: We report a case of a 23-year-old white woman with a history of intravenous drug abuse who presented with acute heart failure. Transthoracic echocardiography failed to show valvular vegetation, but high clinical suspicion led to transesophageal imaging that demonstrated infiltrative prosthetic valve endocarditis causing severe mitral stenosis. Despite extensive efforts from a multidisciplinary team, she died as a result of her critical illness. CONCLUSIONS: The discussion of this case highlights endocarditis physiology, the notable absence of stenosis in modified Duke criteria, and the utility of transesophageal echocardiography in clinching a diagnosis. It advances our knowledge of how endocarditis manifests, and serves as a valuable lesson for clinicians treating similar patients who present with stenosis but no regurgitation on transthoracic imaging, as a decision to forego a transesophageal echocardiography could cause this serious complication of endocarditis to be missed.

Endoscopic repair of a gluteus medius tear at the musculotendinous junction.

Abductor tendon tears are an increasingly recognized clinical entity in patients with lateral thigh pain and weakness. These "rotator cuff tears of the hip" typically result from chronic, nontraumatic rupture of the anterior fibers of the gluteus medius. Although the abductor tendon typically tears from the osseous insertion, the case discussed here ruptured at the musculotendinous junction. This is the first report of this abductor tear subtype and its endoscopic repair.