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1.
JACC Case Rep ; 3(4): 614-618, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34317588

RESUMEN

This case series demonstrates 2 innovative approaches to successful coronary sinus lead placement in the setting of coronary sinus ostial atresia. Use of venous phase coronary angiography, a computed tomography scan with venous phase, or a left-sided upper extremity venogram may help reveal a variant anatomy and guide tool selection. (Level of Difficulty: Advanced.).

2.
Biochemistry ; 48(2): 433-41, 2009 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-19099423

RESUMEN

The role of intersubunit side chain-side chain interactions in the stability of the Escherichia coli aspartate aminotransferase (eAATase) homodimer was investigated by directed mutagenesis at 10 different interface contacts. The urea-mediated unfolding pathway of this enzyme proceeds through the formation of a dimeric intermediate, D*, that retains only 40% of the native enzyme secondary structure as judged by circular dichroism. Disruption of any single intersubunit interaction results in a >2.6 kcal mol(-1) decrease in native state stability, independent of its location or nature. However, the stability of D* with respect to U, the unfolded monomer, is the same for all mutants. The stability of the eAATase interface cannot be ascribed to the contribution of a few hot spots, or to the accumulation of a large number of weak interactions, but only to the presence of multiple important and interconnected interactions. It is proposed that a "molten interface" structure, flexible enough to accommodate point mutations, accounts for the stability of D*. Nuclei of tertiary structure, which are not involved in native intersubunit contacts, likely provide a scaffold for the unstructured interface of D*. Such a scaffold would account for the cooperative unfolding of the intermediate.


Asunto(s)
Aspartato Aminotransferasas/química , Proteínas de Escherichia coli/química , Escherichia coli/enzimología , Alanina/metabolismo , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Aspartato Aminotransferasas/genética , Aspartato Aminotransferasas/metabolismo , Sitios de Unión , Dicroismo Circular , Estabilidad de Enzimas , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Enlace de Hidrógeno , Cinética , Modelos Biológicos , Datos de Secuencia Molecular , Peso Molecular , Desnaturalización Proteica , Pliegue de Proteína , Estructura Cuaternaria de Proteína , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Electricidad Estática , Termodinámica , Urea/farmacología
3.
J Interv Card Electrophysiol ; 49(1): 75-82, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28374072

RESUMEN

PURPOSE: Pressure waveform analysis has the potential for facilitated assessment of pulmonary vein occlusion during cryoballoon ablation for atrial fibrillation. Data on clinical outcomes using this method are lacking. We sought to validate through clinical outcomes the use of pressure waveform analysis as the primary method of determining pulmonary vein occlusion during cryoballoon ablation. METHODS: A study was performed of 122 consecutive patients with atrial fibrillation (85% paroxysmal) undergoing cryoballoon ablation from May 2014 through July 2015 at a single institution using pressure waveform analysis as the primary method of assessing pulmonary vein occlusion. RESULTS: Cryoballoon ablation, with additional segmental radiofrequency ablation in 13.7%, resulted in complete pulmonary vein isolation in 100% of patients. The single procedure freedom from recurrence of atrial arrhythmia beyond the initial 3-month post-ablation was 81.2% at a mean follow-up of 237 days. Recurrence of atrial arrhythmia within 3-month post-ablation was 11.1%, and predicted recurrence beyond 3 months. Repeat ablation was performed in 12.0% of patients. CONCLUSIONS: In the largest study to date on this topic and the only study to focus on clinical outcomes, pressure waveform analysis as the primary method of determining pulmonary vein occlusion in cryoballoon ablation of atrial fibrillation resulted in acute and long-term procedural success rates comparable to those reported with use of routine pulmonary venography. Controlled study is needed to confirm these findings and to determine if this technique affects variables such as procedure duration and radiation exposure.


Asunto(s)
Fibrilación Atrial/diagnóstico por imagen , Fibrilación Atrial/cirugía , Determinación de la Presión Sanguínea/métodos , Ablación por Catéter/métodos , Criocirugía/métodos , Monitoreo Intraoperatorio/métodos , Venas Pulmonares/cirugía , Femenino , Sistema de Conducción Cardíaco/diagnóstico por imagen , Sistema de Conducción Cardíaco/cirugía , Humanos , Masculino , Persona de Mediana Edad , Flebografía/métodos , Venas Pulmonares/diagnóstico por imagen , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Cirugía Asistida por Computador/métodos , Resultado del Tratamiento
4.
Front Neurol ; 6: 57, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25852636

RESUMEN

BACKGROUND: The left atrial septal pouch (LASP), an anatomic variant of the interatrial septum, has uncertain clinical significance. We examined the association between LASP and ischemic stroke subtypes in patients undergoing transesophageal echocardiography (TEE). METHODS: We determined the prevalence of LASP among consecutive patients who underwent TEE at our institution. Patients identified with ischemic strokes were further evaluated for stroke subtype using standard and modified criteria from the Trial of Org 10172 in Acute Stroke Treatment (TOAST). We compared the prevalence of LASP in ischemic stroke, cryptogenic stroke, and non-stroke patients using prevalence ratios (PR). RESULTS: The mean age of all 212 patients (including stroke and non-stroke patients) was 57 years. The overall prevalence of LASP was 17% (n = 35). Of the 75 patients who were worked-up for stroke at our institution during study period, we classified 31 as cryptogenic using standard TOAST criteria. The prevalence of LASP among cryptogenic stroke patients (using standard and modified TOAST criteria) was increased compared to the prevalence among other ischemic stroke patients (26 vs. 9%, p = 0.06; PR = 1.8, 95% CI = 1.1-3.1, and 30 vs. 10%, p = 0.04; PR = 2.2, 95% CI = 1.2-4.1, respectively). CONCLUSION: In this population of relatively young patients, prevalence of LASP was increased in cryptogenic stroke compared to stroke patients of other subtypes. These findings suggest LASP is associated with cryptogenic stroke, which should be verified by future large-scale studies.

5.
Am J Cardiol ; 111(8): 1104-10, 2013 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-23360768

RESUMEN

The aim of this study was to investigate the impact of morbid obesity (body mass index ≥40 kg/m(2)) on in-hospital mortality and coronary revascularization outcomes in patients presenting with acute myocardial infarctions (AMI). The Nationwide Inpatient Sample of the Healthcare Cost and Utilization Project was used, and 413,673 patients hospitalized with AMIs in 2009 were reviewed. Morbidly obese patients constituted 3.7% of all patients with AMIs. Analysis of the unadjusted data revealed that morbidly obese patients compared with those not morbidly obese were more likely to undergo any invasive cardiac procedures when presenting with either ST-segment elevation myocardial infarction (97.4% vs 93.8%, p <0.0001) or non-ST-segment elevation myocardial infarction (85.5% vs 80.6%, p <0.0001). The unadjusted mortality rate for morbidly obese patients with AMIs was 3.5%, compared with 5.5% of those not obese (p <0.0001). After adjustment, lower odds of mortality in those morbidly obese compared to those not morbidly remained. In conclusion, patients with morbid obesity had lower odds of in-hospital mortality, compared to those not morbidly obese, consistent with the phenomenon of the "obesity paradox."


Asunto(s)
Mortalidad Hospitalaria , Infarto del Miocardio/mortalidad , Infarto del Miocardio/terapia , Obesidad Mórbida/complicaciones , Obesidad Mórbida/mortalidad , Anciano , Análisis de Varianza , Índice de Masa Corporal , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Tasa de Supervivencia , Resultado del Tratamiento , Estados Unidos/epidemiología
6.
Int J Cardiol ; 152(3): 369-74, 2011 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-20843568

RESUMEN

OBJECTIVE: This meta-analysis was performed to assess the efficacy and safety of bivalirudin compared with unfractionated heparin or enoxaparin plus glycoprotein (GP) IIb/IIIa inhibitors in patients undergoing percutaneous coronary intervention (PCI). BACKGROUND: Pharmacotherapy for patients undergoing PCI includes bivalirudin, heparin, and GP IIb/IIIa inhibitors. We sought to compare ischemic and bleeding outcomes with bivalirudin versus heparin plus GP IIb/IIIa inhibitors in patients undergoing PCI. METHODS: A literature search was conducted to identify fully published randomized trials that compared bivalirudin with heparin plus GP IIb/IIIa inhibitors in patients undergoing PCI. RESULTS: A total of 19,772 patients in 5 clinical trials were included in the analysis (9785 patients received bivalirudin and 9987 patients received heparin plus GP IIb/IIIa inhibitors during PCI). Anticoagulation with bivalirudin, as compared with heparin plus glycoprotein IIb/IIIa inhibitors, results in no difference in major adverse cardiovascular events (odds ratio [OR] 1.07, 95% confidence interval [CI] 0.96 to 1.19), death (OR 0.93, 95% CI 0.72 to 1.21), or urgent revascularization (OR 1.06, 95% CI 0.86 to 1.30). There is a trend towards a higher risk of myocardial infarction (OR 1.12, 95% CI 0.99 to 1.28) but a significantly lower risk of TIMI major bleeding with bivalirudin (OR 0.55, 95% CI 0.44 to 0.69). CONCLUSION: In patients who undergo PCI, anticoagulation with bivalirudin as compared with unfractionated heparin or enoxaparin plus GP IIb/IIIa inhibitors results in similar ischemic adverse events but a reduction in major bleeding.


Asunto(s)
Angioplastia Coronaria con Balón , Heparina/administración & dosificación , Hirudinas/administración & dosificación , Fragmentos de Péptidos/administración & dosificación , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/antagonistas & inhibidores , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Angioplastia Coronaria con Balón/efectos adversos , Enfermedades Cardiovasculares/inducido químicamente , Enfermedades Cardiovasculares/epidemiología , Quimioterapia Combinada , Humanos , Inhibidores de Agregación Plaquetaria/administración & dosificación , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/metabolismo , Proteínas Recombinantes/administración & dosificación
7.
Am J Cardiol ; 105(8): 1070-5, 2010 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-20381655

RESUMEN

The aim of this study was to compare the safety and efficacy of coronary artery bypass grafting (CABG) with percutaneous coronary intervention (PCI) using drug-eluting stents (DES) in patients with unprotected left main coronary artery (ULMCA) disease. The current American College of Cardiology and American Heart Association guidelines recommend CABG for the treatment of patients with ULMCA disease on the basis of clinical trials demonstrating a survival benefit with CABG compared to medical therapy. DES reduce the rate of target vessel revascularization compared with bare-metal stents in ULMCA PCI and may be a safe alternative to CABG. A meta-analysis was conducted of clinical studies comparing CABG and PCI with DES for ULMCA disease with respect to death; the composite of death, myocardial infarction, or stroke; and target vessel revascularization at 1 year follow-up. The analysis included 2,905 patients from 8 clinical studies (2 randomized trials and 6 nonrandomized studies). At 1-year follow-up, there was no significant difference between the CABG and DES groups in the risk for death (odds ratio [OR] 1.12, 95% confidence interval [CI] 0.80 to 1.56) or the composite end point of death, myocardial infarction, or stroke (OR 1.25, 95% CI 0.86 to 1.82). The risk for target vessel revascularization was significantly lower in the CABG group compared to the PCI group (OR 0.44, 95% CI 0.32 to 0.59). In conclusion, PCI with DES is safe and could represent a good alternative to CABG for selected cases in patients with ULMCA disease.


Asunto(s)
Angioplastia Coronaria con Balón/instrumentación , Puente de Arteria Coronaria/métodos , Estenosis Coronaria/terapia , Stents Liberadores de Fármacos , Angiografía Coronaria , Estenosis Coronaria/diagnóstico por imagen , Humanos , Resultado del Tratamiento
8.
Am J Cardiol ; 105(11): 1540-4, 2010 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-20494658

RESUMEN

This meta-analysis was undertaken to assess the efficacy and safety of coronary artery bypass grafting (CABG) compared to drug-eluting stenting (DES) in patients with diabetes mellitus and multivessel coronary artery disease (CAD). CABG has been the preferred revascularization strategy in patients with diabetes compared to DES. Drug-eluting stents reduce the rate of target vessel revascularization compared to bare-metal stents. The ideal revascularization strategy for patients with diabetes with multivessel CAD in the DES era is unknown. A search of published reports was performed to identify clinical studies comparing CABG with DES in patients with diabetes with multivessel CAD with a minimum follow-up of 1 year. Five studies including 1,543 patients with diabetes (757 who underwent CABG and 786 who underwent DES) met the selection criteria. The mean follow-up period was 18 months (range 12 to 36). Compared to DES, CABG was associated with a lower risk for major adverse cardiac events (odds ratio [OR] 0.48, 95% confidence interval [CI] 0.36 to 0.65), driven mainly by a lower risk for repeat revascularization (OR 0.18, 95% CI 0.11 to 0.30), despite having a higher percentage of triple-vessel disease. There was no significant difference in death (OR 0.85, 95% CI 0.52 to 1.39) or myocardial infarction (OR 0.82, 95% CI 0.41 to 1.61). Patients in the CABG group had a higher risk for cerebrovascular events (OR 2.15, 95% CI 0.99 to 4.68). In conclusion, PCI with DES is safe and may represent a viable alternative to CABG for selected patients with diabetes with multivessel CAD.


Asunto(s)
Angioplastia Coronaria con Balón , Puente de Arteria Coronaria , Enfermedad de la Arteria Coronaria/patología , Enfermedad de la Arteria Coronaria/terapia , Vasos Coronarios/patología , Complicaciones de la Diabetes/terapia , Stents Liberadores de Fármacos , Enfermedad de la Arteria Coronaria/complicaciones , Complicaciones de la Diabetes/patología , Humanos , Oportunidad Relativa , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
9.
Am J Cardiol ; 106(3): 337-41, 2010 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-20643242

RESUMEN

This study was designed to compare the safety and efficacy of sirolimus-eluting stents (SESs) to paclitaxel-eluting stents (PESs) in percutaneous intervention of saphenous vein graft (SVG) lesions. SVGs develop atherosclerosis at high rates and often require repeat revascularization. Percutaneous intervention with drug-eluting stents has become the preferred method of revascularization due to higher restenosis with bare metal stents and increased morbidity and mortality with repeat coronary artery bypass grafting. We sought to compare the rate of major adverse cardiac events and stent thrombosis between SESs and PESs in patients undergoing SVG intervention. A multicenter analysis of 172 patients with SVG lesions treated with SESs or PESs was performed. The 30-day and 1-year clinical outcomes of 102 patients receiving SESs were compared to those of 70 patients receiving PESs. There was no significant difference in baseline demographic, angiographic, and procedural characteristics between the SES and PES treatment groups. There was no statistical difference in major adverse cardiac events at 30 days and at 1 year (hazard ratio [HR] 1.58, 95% confidence interval [CI] 0.77 to 3.23, log-rank p = 0.21). There was also no difference in survival (HR 1.28, 95% CI 0.39 to 4.25, log-rank p = 0.69) or target vessel revascularization (HR 2.54, 95% CI 0.84 to 7.72, log-rank p = 0.09). In conclusion, this multicenter analysis of real-world patients demonstrated that SESs and PESs have similar clinical outcomes when used in SVG intervention.


Asunto(s)
Puente de Arteria Coronaria/métodos , Reestenosis Coronaria/prevención & control , Stents Liberadores de Fármacos , Oclusión de Injerto Vascular/prevención & control , Inmunosupresores/administración & dosificación , Paclitaxel/administración & dosificación , Vena Safena/trasplante , Sirolimus/administración & dosificación , Anciano , California/epidemiología , Distribución de Chi-Cuadrado , Comorbilidad , Angiografía Coronaria , Puente de Arteria Coronaria/mortalidad , Reestenosis Coronaria/mortalidad , Femenino , Oclusión de Injerto Vascular/mortalidad , Humanos , Masculino , Modelos de Riesgos Proporcionales , Sistema de Registros , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del Tratamiento
10.
Pediatr Neurosurg ; 38(4): 167-73, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12646734

RESUMEN

Intracranial schwannomas not arising from the facial, trigeminal, or vestibular nerves in the absence of neurofibromatosis are extremely rare. We report a case of a schwannoma arising in the region of the anterior tentorial hiatus and posterior cavernous sinus. A 17-year old girl presented with headaches and intermittent diplopia. An MRI of the brain revealed a heterogeneously enhancing mass adjacent to the free edge of the tentorium, superior to the cerebellopontine angle. An orbitozygomatic pterional craniotomy was done with complete resection of the tumor. Postoperatively, the patient remained neurologically intact. The clinical presentation and treatment of schwannomas arising in this location are discussed.


Asunto(s)
Seno Cavernoso/patología , Neoplasias de los Nervios Craneales/patología , Neurilemoma/patología , Enfermedades del Nervio Troclear/patología , Nervio Troclear/patología , Adolescente , Seno Cavernoso/diagnóstico por imagen , Seno Cavernoso/cirugía , Neoplasias de los Nervios Craneales/diagnóstico por imagen , Neoplasias de los Nervios Craneales/cirugía , Femenino , Humanos , Imagen por Resonancia Magnética , Neurilemoma/diagnóstico por imagen , Neurilemoma/cirugía , Tomografía Computarizada por Rayos X , Nervio Troclear/diagnóstico por imagen , Nervio Troclear/cirugía , Enfermedades del Nervio Troclear/diagnóstico por imagen , Enfermedades del Nervio Troclear/cirugía
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