Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 24
Filtrar
Más filtros

Base de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Ann Pharmacother ; 55(5): 575-583, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-32964730

RESUMEN

BACKGROUND: Accurate monitoring of intravenous unfractionated heparin (UFH) is essential to mitigate the risk of adverse drug events associated with dosing errors. Although recent data support anti-factor Xa (anti-Xa) monitoring preferentially over activated partial thromboplastin time (aPTT) to improve time to therapeutic anticoagulation, the utility of incorporating anti-Xa monitoring with a calculation-free weight-based UFH nomogram has not been formally evaluated. OBJECTIVE: The primary objective of this study was to evaluate the time to therapeutic anticoagulation of a calculation-free weight-based UFH nomogram integrated with anti-Xa monitoring versus a historical control of aPTT monitoring utilizing manual dose calculations. METHODS: This was a retrospective analysis of patients with anti-Xa monitoring and a novel calculation-free weight-based UFH nomogram compared with a historical control with aPTT monitoring and manual calculations. RESULTS: A total of 103 patients in the aPTT cohort and 100 patients in the anti-Xa cohort were analyzed. The anti-Xa cohort achieved goal therapeutic target 3.8 hours sooner than the aPTT cohort (P = 0.03). Patients with anti-Xa monitoring required 1 fewer adjustment per 2.5 patient-days of UFH with the venous thromboembolism nomogram (P = 0.02). Patients in the aPTT cohort required more infusion interruptions because of supratherapeutic values (P = 0.007) and boluses because of subtherapeutic values (P = 0.044). There were no differences in rates of thromboembolism, major bleeding, or clinically relevant nonmajor bleeding between the cohorts. CONCLUSION AND RELEVANCE: This study demonstrated that anti-Xa UFH monitoring integrated with a calculation-free nomogram results in faster time to therapeutic anticoagulation and fewer dose adjustments compared with aPTT monitoring with manual calculations.


Asunto(s)
Anticoagulantes/administración & dosificación , Monitoreo de Drogas/métodos , Inhibidores del Factor Xa/administración & dosificación , Heparina/administración & dosificación , Nomogramas , Anciano , Anciano de 80 o más Años , Anticoagulantes/efectos adversos , Coagulación Sanguínea/efectos de los fármacos , Coagulación Sanguínea/fisiología , Estudios de Cohortes , Monitoreo de Drogas/normas , Inhibidores del Factor Xa/efectos adversos , Hemorragia/sangre , Hemorragia/inducido químicamente , Heparina/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Tiempo de Tromboplastina Parcial/métodos , Tiempo de Tromboplastina Parcial/normas , Estudios Retrospectivos , Tromboembolia/sangre , Tromboembolia/tratamiento farmacológico
2.
Acta Crystallogr E Crystallogr Commun ; 75(Pt 10): 1436-1444, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31636972

RESUMEN

The title compounds, 4-(5-acetamido-3-acetyl-2-methyl-2,3-di-hydro-1,3,4-thia-diazol-2-yl)phenyl benzoate, C20H19N3O4S (I), 4-(5-acetamido-3-acetyl-2-methyl-2,3-di-hydro-1,3,4-thia-diazol-2-yl)phenyl isobutyrate 0.25-hydrate, C17H21N3O4S·0.25H2O (II), 4-(5-acetamido-3-acetyl-2-methyl-2,3-di-hydro-1,3,4-thia-diazol-2-yl)phenyl propionate, C16H19N3O4S (III) and 4-(5-acetamido-3-acetyl-2-methyl-2,3-di-hydro-1,3,4-thia-diazol-2-yl)phenyl cinnamate chloro-form hemisolvate, C22H21N3O4S·0.5CHCl3 (IV), all crystallize with two independent mol-ecules (A and B) in the asymmetric unit in the triclinic P space group. Compound II crystallizes as a quaterhydrate, while compound IV crystallizes as a chloro-form hemisolvate. In compounds I, II, III (mol-ecules A and B) and IV (mol-ecule A) the five-membered thia-diazole ring adopts an envelope conformation, with the tetra-substituted C atom as the flap. In mol-ecule B of IV this ring is flat (r.m.s. deviation 0.044 Å). The central benzene ring is in general almost normal to the mean plane of the thia-diazole ring in each mol-ecule, with dihedral angles ranging from 75.8 (1) to 85.5 (2)°. In the crystals of all four compounds, the A and B mol-ecules are linked via strong N-H⋯O hydrogen bonds and generate centrosymmetric four-membered R 4 4(28) ring motifs. There are C-H⋯O hydrogen bonds present in the crystals of all four compounds, and in I and II there are also C-H⋯π inter-actions present. The inter-molecular contacts in the crystals of all four compounds were analysed using Hirshfeld surface analysis and two-dimensional fingerprint plots.

3.
Langmuir ; 33(42): 11687-11697, 2017 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-28862866

RESUMEN

Gibbs developed the thermodynamics of a liquid-vapor system by introducing the idea of a "dividing surface" a hypothetical surface that separates the system into two homogeneous phases. The area and curvatures of a conveniently chosen dividing surface, the "surface of tension", are used to account for the effects of the smooth variation of properties across the actual transition layer between the phases. Tolman (1948, 1949) considered a more detailed model of the interfacial region and obtained expressions for surface tension (σ) and the location of the surface of tension. Based on qualitative arguments, Tolman's model introduced a surface of tension, such that the pressure (P) increases from its saturation value (Psat) to a maximum value (Pmax) as the surface is approached from the vapor side and decreases from (Psat) to its minimum value (Pmin) as the surface is approached from the liquid side. Assuming an exponential decay of (P) away from the surface, Tolman obtained an explicit expression for (σ) in terms of Psat, Pmax, Pmin, and two length scales. In the this work, the Gibbs-Tolman (GT) model is used along with the Lee and Kesler (1975) equation of state. The model is augmented to take into account the effect of the density gradient in the transition zone and a 4-parameter augmented model (AGT model) is proposed. The GT and AGT models are shown to fit the data for 152 pure liquids with an absolute average deviation (AAD) of 4.91% and 2.02%, respectively. The corresponding AAD values for 57 liquid mixtures are 4.2% and 3.0% respectively. Arguments are also presented to counter some of the fundamental concerns that have been raised about the GT approach. Although the model correlates the data very well, one of the length parameters turns out to be persistently negative, and the reason for this behavior is not clear.

4.
Int J Cardiovasc Imaging ; 33(6): 771-778, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28120155

RESUMEN

Objectives The aim of this study was to quantify the radiation dose reduction during coronary angiography and percutaneous coronary intervention (PCI) through removal of the anti-scatter grid (ASG), and to assess its impact on image quality in adult patients with a low body mass index (BMI). Methods A phantom with different thicknesses of acrylic was used with a Westmead Test Object to simulate patient sizes and assess image quality. 129 low BMI patients underwent coronary angiography or PCI with or without the ASG in situ. Radiation dose was compared between both patient groups. Results With the same imaging system and a comparable patient population, ASG removal was associated with a 47% reduction in total dose-area product (DAP) (p < 0.001). Peak skin dose was reduced by 54% (p < 0.001). Operator scatter was reduced to a similar degree and was significantly reduced through removal of the ASG. Using an image quality phantom it was demonstrated that image quality remained satisfactory. Conclusions Removal of the ASG is a simple and effective method to significantly reduce radiation dose in coronary angiography and PCI. This was achieved while maintaining adequate diagnostic image quality. Selective removal of the ASG is likely to improve the radiation safety of cardiac angiography and interventions.


Asunto(s)
Angiografía Coronaria/instrumentación , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/terapia , Exposición Profesional/prevención & control , Dosis de Radiación , Exposición a la Radiación/prevención & control , Radiografía Intervencional/instrumentación , Dispersión de Radiación , Anciano , Anciano de 80 o más Años , Índice de Masa Corporal , Angiografía Coronaria/efectos adversos , Diseño de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Exposición Profesional/efectos adversos , Seguridad del Paciente , Intervención Coronaria Percutánea/efectos adversos , Intervención Coronaria Percutánea/instrumentación , Fantasmas de Imagen , Proyectos Piloto , Valor Predictivo de las Pruebas , Exposición a la Radiación/efectos adversos , Radiografía Intervencional/efectos adversos , Factores de Riesgo , Stents
5.
EuroIntervention ; 12(8): e939-e947, 2016 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-27721210

RESUMEN

AIMS: The aim of this study was to evaluate whether a real-time (RT) colour pictorial radiation dose monitoring system reduces patient skin and total radiation dose during coronary angiography and intervention. METHODS AND RESULTS: Patient demographics, procedural variables and radiation parameters were recorded before and after institution of the RT skin dose recording system. Peak skin dose as well as traditionally available measures of procedural radiation dose were compared. A total of 1,077 consecutive patients underwent coronary angiography, of whom 460 also had PCI. Institution of the RT skin dose recording system resulted in a 22% reduction in peak skin dose after accounting for confounding variables. Radiation dose reduction was most pronounced in those having PCI but was also seen over a range of subgroups including those with prior coronary artery bypass surgery, high BMI, and with radial arterial access. This was associated with a significant reduction in the number of patients placed at risk of skin damage. Similar reductions in parameters reflective of total radiation dose were also demonstrated after institution of RT radiation monitoring. CONCLUSIONS: Institution of an RT skin dose recording reduced patient peak skin and total radiation dose during coronary angiography and intervention. Consideration should be given to widespread adoption of this technology.


Asunto(s)
Cateterismo Cardíaco/métodos , Angiografía Coronaria/métodos , Fluoroscopía/métodos , Intervención Coronaria Percutánea/métodos , Dosis de Radiación , Exposición a la Radiación/prevención & control , Monitoreo de Radiación/métodos , Piel , Anciano , Anciano de 80 o más Años , Índice de Masa Corporal , Puente de Arteria Coronaria , Femenino , Arteria Femoral , Reserva del Flujo Fraccional Miocárdico , Humanos , Análisis de Series de Tiempo Interrumpido , Modelos Lineales , Masculino , Persona de Mediana Edad , Tempo Operativo , Arteria Radial , Monitoreo de Radiación/instrumentación
6.
Appl Clin Inform ; 7(3): 660-71, 2016 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-27453336

RESUMEN

PURPOSE: To evaluate the performance of using trigger words (e.g. clues to an adverse drug reaction) in unstructured, narrative text to detect adverse drug reactions (ADRs) and compare the use of these trigger words to a targeted chart review for ADR detection within the intensive care unit (ICU) discharge summary note. MATERIALS: A retrospective medical record review was conducted. Evaluation of ADRs occurred in two phases - targeted chart review of the ICU discharge summary notes in Phase 1 and targeted chart review using specific words and phrases as triggers for ADRs in Phase 2. RESULTS: Four hundred ADRs were documented in 223 patients for Phase 1. For Phase 2, there were 219 ADRs identified in 120 patients. 138 real or accurate ADRs were identified from Phase 1 and 47 duplicate events. 34 ADRs from Phase 2 were not identified in Phase 1. Fifteen of the ADRs were inaccurately presumed in Phase 2. Fifty-eight of 127 text triggers identified at least one ADR. Low and moderate frequency trigger words were more likely to have PPVs > 5%. CONCLUSIONS: Targeted chart review using specific words and phrases as triggers for ADRs is a reasonable approach to identify ADRs and may save time compared to other methods after further refinement leads to a more accurately performing trigger word list.


Asunto(s)
Sistemas de Registro de Reacción Adversa a Medicamentos , Minería de Datos , Registros Electrónicos de Salud , Unidades de Cuidados Intensivos , Alta del Paciente , Semántica , Femenino , Humanos , Masculino , Persona de Mediana Edad
7.
Pharmacoepidemiol Drug Saf ; 22(5): 510-6, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23440931

RESUMEN

PURPOSE: This study aimed to determine the frequency and type of adverse drug events (ADEs) identified in intensive care unit (ICU) transfer summaries and in the hospital discharge summaries to demonstrate the effectiveness of ICU transfer summary surveillance in the identification of ADEs. METHODS: A retrospective electronic medical record review was conducted for medical ICU patients admitted between January 2009 and April 2009 to a large, academic medical center. The Harvard Practice Scale and the modified Leonard Assessment Scale were used to evaluate the presence of an ADE from the ICU transfer and hospital discharge summaries. RESULTS: Two hundred and fifty-four patients were identified for inclusion with a median medical ICU length of stay of 4.5 days and hospital length of stay of 13 days. The ICU transfer summary review revealed 173 ADEs among 124 unique patients with a rate of 33.9 ADEs per 1000 hospital patient days. Sixty-nine ADEs among 63 unique patients were identified through the hospital discharge summary with a rate of 13.5 ADEs per 1000 hospital patient days. Only 23.1% of ADEs discussed in the ICU transfer summary were also discussed in the hospital discharge summary. CONCLUSIONS: The use of ICU transfer summaries is an effective tool to increase ADE detection. The use of an ICU transfer summary should be considered as an adjunct method to an existing ADE surveillance system for heightened pharmacovigilance.


Asunto(s)
Sistemas de Registro de Reacción Adversa a Medicamentos/estadística & datos numéricos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Registros Electrónicos de Salud/estadística & datos numéricos , Unidades de Cuidados Intensivos/estadística & datos numéricos , Adulto , Anciano , Enfermedad Crítica , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Alta del Paciente/estadística & datos numéricos , Transferencia de Pacientes/estadística & datos numéricos , Estudios Retrospectivos
8.
Heart Lung Circ ; 20(2): 111-8, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20943440

RESUMEN

BACKGROUND: persistent ST elevation after reperfused ST elevation myocardial infarction (STEMI) is believed to be related to poor microvascular perfusion. Cardiac magnetic resonance imaging (CMR) can evaluate microvascular obstruction (MVO) and intramyocardial haemorrhage (IMH) both of which represent severe microvascular damage, have independent prognostic value and are dynamic and evolving over the first 48hours after reperfusion. The aim of this study was to assess whether the development of MVO or IMH has an impact upon ST segment resolution. METHODS: patients undergoing primary percutaneous coronary intervention (PCI) for STEMI had serial 12 lead electrocardiograms (ECG) from one hour after PCI until discharge. Persistent single lead maximal residual ST elevation (maxSTE) at each time point was calculated. ST segment deterioration (re-elevation) was calculated on each ECG until discharge compared with one hour post PCI ECG. CMR was performed within seven days post infarct utilising T2 weighted imaging to evaluate culprit artery area at risk (AAR) and IMH. Gadolinium delayed enhancement CMR quantified infarct size and MVO. RESULTS: in the 41 patients studied 58% had MVO and 41% had IMH. ST segment deterioration was more common in those with MVO or IMH (p=0.03 and p=0.008 respectively). MaxSTE was higher at each time point after PCI in those with MVO but only became statistically significant after 24hours. The measurement of maxSTE at 48 or 72hours after revascularisation provided the best correlation with the combination of infarct size, AAR, MVO and intramyocardial haemorrhage. CONCLUSION: microvascular injury as defined on CMR is associated with dynamic changes and persistence of ST segment elevation in the first 72hours after reperfusion.


Asunto(s)
Circulación Coronaria , Electrocardiografía , Imagen por Resonancia Magnética , Microcirculación , Infarto del Miocardio , Reperfusión Miocárdica , Anciano , Angioplastia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico por imagen , Infarto del Miocardio/fisiopatología , Infarto del Miocardio/terapia , Radiografía , Factores de Tiempo
9.
J Electrocardiol ; 44(1): 49-57, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21168001

RESUMEN

BACKGROUND: Grade 3 ischemia during ST elevation myocardial infarction (STEMI) is defined as ST elevation with distortion of the terminal portion of the QRS on electrocardiogram (ECG). The aim of this study was to evaluate the effect of ischemic grade on cardiac magnetic resonance (CMR) imaging infarct characteristics such as infarct size, microvascular obstruction (MVO), intramyocardial hemorrhage (IMH), and myocardial salvage. METHODS: Patients with STEMI treated with primary percutaneous coronary intervention had a 12-lead ECG on presentation for analysis of ischemic grade. Gadolinium-enhanced CMR imaging was performed within 7 days to assess infarct size, MVO, IMH, and myocardial salvage. RESULTS: Of the 37 patients enrolled in the study, grade 3 ischemia was present in 32%. Those with grade 3 ischemia had higher peak troponin I levels (P = .013), more MVO (P < .001), more IMH (P < .001), larger infarct size (P = .025), and less myocardial salvage (P = .012). Regression analysis found that grade 3 ischemia, infarct size, and peak troponin I level were significantly associated with MVO and IMH. CONCLUSION: Grade 3 ischemia on the admission ECG during STEMI is closely associated with the development of severe microvascular damage on CMR imaging.


Asunto(s)
Electrocardiografía/métodos , Imagen por Resonancia Cinemagnética/métodos , Microvasos/patología , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/patología , Anciano , Femenino , Humanos , Masculino , Microcirculación , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Estadística como Asunto
10.
Heart Lung Circ ; 19(4): 234-42, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20144559

RESUMEN

BACKGROUND: To assess the role of serum thromboxane B(2) (TXB(2)) measurements and the correlation between platelet function studies, in patients with stable cardiovascular disease on aspirin or clopidogrel. METHODS: 76 patients (47 on aspirin, 16 clopidogrel, 13 both) underwent assessment of TXB(2), whole blood aggregometry (WBA) after stimulation with (i) arachidonic acid (0.5mM), (ii) ADP (5 microM), (iii) collagen (1 and 5 microg/ml), PFA-100, and Cone and Plate Analyzer. Clopidogrel patients were additionally assessed by the VerifyNow System. RESULTS: TXB(2) values ranged between 0.2 and 56.2 ng/ml, with significant separation between those taking aspirin, clopidogrel and controls (0.45 ng/ml vs 6.85 ng/ml vs 12.97 ng/ml, p<0.001). There was moderate correlation between WBA-AA and TXB(2) (r=0.487, p<0.001), PFA-100((R)) (r=0.599, p<0.001), WBA-Col1 (r=0.424, p<0.001), WBA-Col1:5 (r=0.417, p<0.001), and between TXB(2) and PFA-100((R)) (r=0.509, p<0.001). The prevalence of aspirin non-responders for WBA-AA, TXB(2), PFA-100((R)), CPA and Coll1:5 was 13.1%, 8.2%, 14.8%, 9.7% and 16.4% respectively. Individual patients were not consistently classified as aspirin non-responders in all tests. Those with inadequate aspirin response on > or =3 tests had higher TXB(2) levels (mean 1.57+/-1.66, range 0.553-4.45 vs mean 0.45+/-0.18, range 0.23-1.50) (p=0.001). Clopidogrel suppressed TXB(2) (p=0.02), WBA-AA (p<0.001), WBA-Col1 (p=0.012) and WBA-ADP (p<0.001) compared to controls. TXB(2) in patients ingesting fish oil tablets was lower compared to those without (0.4 ng/ml vs 0.52 ng/ml, p=0.004). Obesity was associated with higher TXB(2) values (0.61 vs 0.41, p=0.01). CONCLUSION: Serum TXB(2) measurements are a direct measure of the pharmacological effect of aspirin, are easily performed and correlate with other measures of platelet function. Serum TXB(2) measurements could be a useful sole measure of aspirin non-response, and may be even more predictive when performed in tandem with a global measure of platelet function. Aspirin and clopidogrel both suppressed several platelet pathways.


Asunto(s)
Aspirina/uso terapéutico , Enfermedades Cardiovasculares/tratamiento farmacológico , Tromboxano B2/sangre , Adulto , Anciano , Anciano de 80 o más Años , Aspirina/farmacología , Presión Sanguínea/efectos de los fármacos , Estudios de Casos y Controles , Clopidogrel , Femenino , Aceites de Pescado , Humanos , Masculino , Persona de Mediana Edad , Agregación Plaquetaria/efectos de los fármacos , Inhibidores de Agregación Plaquetaria , Pruebas de Función Plaquetaria , Estadística como Asunto , Estadísticas no Paramétricas , Encuestas y Cuestionarios , Ticlopidina/análogos & derivados , Ticlopidina/uso terapéutico
11.
Int J Cardiol ; 139(3): e36-8, 2010 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-19168239

RESUMEN

Multivessel coronary ventricular fistulae is a rare coronary anomaly whose origin is believed to be from an arterioluminal or arteriosinusoidal connection with the ventricle. The clinical and haemodynamic significance of these fistulae have been a source of controversy despite varying methods of evaluation. A 69 year old female with exertional dyspnoea, atypical chest pain and multivessel coronary to left ventricular fistulae underwent cardiac MRI with adenosine stress. Subendocardial ischaemia was present in multiple coronary territories therefore confirming a coronary steal phenomenon.


Asunto(s)
Anomalías de los Vasos Coronarios/diagnóstico , Isquemia Miocárdica/diagnóstico , Fístula Vascular/diagnóstico , Anciano , Estenosis de la Válvula Aórtica/diagnóstico , Ecocardiografía , Femenino , Humanos , Imagen por Resonancia Cinemagnética
12.
Heart Lung Circ ; 17(3): 215-9, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18242132

RESUMEN

BACKGROUND: Coronary angiography and angioplasty have to date been performed using digital angiography and fluoroscopic systems which incorporate an image intensifier (II). More recently flat-panel (FP) detectors have been introduced which are thought to improve spatial resolution. However, there is limited data on the effect of flat-panel detection on radiation exposure. We sought to determine the impact of flat-panel on cumulative radiation exposure in patients undergoing elective coronary angioplasty at our institution. METHODS: Patients who underwent elective coronary angioplasty in the six months prior to and following upgrade of our Toshiba catheterisation laboratory from image intensifier to flat-panel were included. Demographic and radiation data were collected prospectively and the same five operators performed interventions during the 12-month period. Radiation data was obtained from the dose-area product meter intrinsic to the fluoroscopy system. RESULTS: One hundred and thirty seven patients underwent elective angioplasty over the 12-month period (68 II, 69 FP). Cumulative radiation exposure was increased in flat-panel cases (99, 129 Gy cm(2) versus 71, 77 Gy cm(2), p=0.001). This increase was independent of patient weight (78+/-15 kg versus 78+/-17 kg, p=NS), screening time (19+/-12 min versus 18+/-13 min, p=NS) and total number of digital acquisitions (1475, 820 versus 1668, 1365, p=NS). The total amount of contrast dye did not differ between flat-panel and image intensifier cases (195+/-76 ml versus 194+/-79 ml, p=NS). CONCLUSIONS: Adoption of flat-panel detector technology increases radiation exposure. This may have important safety implications for catheterisation laboratory staff and patients undergoing multiple interventional procedures.


Asunto(s)
Angioplastia Coronaria con Balón , Angiografía Coronaria/efectos adversos , Fluoroscopía/efectos adversos , Anciano , Estudios de Cohortes , Angiografía Coronaria/métodos , Fluoroscopía/métodos , Humanos , Procesamiento de Imagen Asistido por Computador , Persona de Mediana Edad , Fantasmas de Imagen , Dosis de Radiación , Radiometría
13.
Heart Lung Circ ; 16(4): 274-81, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17420156

RESUMEN

AIMS: Nitric oxide (NO) may modulate myocardial ischaemia/reperfusion (I/R) injury, but effects of hypercholesterolaemia on myocardial NO release during I/R are unknown. METHODS: A NO-specific carbon fibre electrode continuously measured coronary sinus [NO] during 60 min low-flow ischaemia (1 ml/min) and 60 min free reperfusion (I/R) in isolated rabbit hearts. Experimental groups (n=7 per group) were control, L-arginine supplement (200 microM), N-nitro-L-arginine methyl ester (L-NAME) treatment (8 microM) and hypercholesterolaemic. RESULTS: During early I, NO release decreased markedly in control (-1356+/-286 pmol/min/g) and L-arginine (-1972+/-172) groups, but less in L-NAME (-441+/-89) and hypercholesterolaemic (-602+/-164) groups (both p<0.01 vs. controls). No increase in NO release during I was seen in any group. After R, NO release increased above baseline in control (+2333+/-591 pmol/min/g) and L-arginine (+1048+/-278) groups and hypercholesterolaemic (+1100+/-478) (p<0.05 vs. pre-ischaemia each group). There was little increase in NO release in the L-NAME group (+436+/-247 pmol/min/g, p<0.05 vs. controls). In each group, myocardial NO release declined towards pre-ischaemic levels during 60 min R. Hearts treated with L-arginine had similar NO release but better functional recovery than controls (p<0.01). Treatment with L-NAME was also associated with better functional recovery than in controls or hypercholesterolaemic hearts. CONCLUSION: Myocardial NO release declines rapidly during ischaemia, but increases above baseline during early reperfusion. Improved function after L-arginine treatment appears to be independent of effects upon NO release. Hypercholesterolaemia is associated with reduced myocardial NO release, under both baseline conditions and during ischaemia and reperfusion.


Asunto(s)
Arginina/farmacología , Hipercolesterolemia/metabolismo , Isquemia Miocárdica/metabolismo , Reperfusión Miocárdica , Miocardio/metabolismo , Óxido Nítrico/metabolismo , Análisis de Varianza , Animales , Circulación Coronaria/efectos de los fármacos , Modelos Animales de Enfermedad , Inhibidores Enzimáticos/farmacología , Isquemia Miocárdica/fisiopatología , Daño por Reperfusión Miocárdica/metabolismo , Daño por Reperfusión Miocárdica/fisiopatología , Miocardio/patología , NG-Nitroarginina Metil Éster/farmacología , Conejos , Proyectos de Investigación , Factores de Tiempo , Presión Ventricular/efectos de los fármacos
14.
Heart Lung Circ ; 15(6): 378-82, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17074534

RESUMEN

BACKGROUND: Patients presenting with acute coronary syndromes (ACS) commonly have a responsible culprit coronary lesion. There is limited data on the natural history of this culprit lesion in the short term and whether there is a change in morphology of this lesion in the days following presentation. Furthermore, the effect of antithrombotic therapy on this process is unknown. METHODS: Sixty-eight patients presenting with ACS had their diagnostic study performed at our institution and had coronary angioplasty performed a few days later at a different hospital. Culprit lesion characteristics including minimum luminal diameter (MLD) and percentage diameter stenosis were determined on each occasion. RESULTS: Acute myocardial infarction patients (n=14) had improved culprit lesion characteristics at angioplasty compared to baseline (diameter stenosis 78.9% versus 62.4%, p<0.01). Similarly, patients presenting with unstable angina (UA) or non-ST elevation myocardial infarction (non-STEMI) (n=54) had improved diameter stenosis (78.0% versus 72.7%, p<0.001). The change in MLD was greater in MI patients than UAP/non-STEMI patients (0.6mm versus 0.16mm, p<0.01). CONCLUSION: Treatment of ACS patients with aspirin with anticoagulant therapy followed by delayed intervention results in angiographic improvement in lesion severity which may provide a more favourable environment in which to undertake percutaneous coronary intervention.


Asunto(s)
Angina de Pecho/patología , Angina de Pecho/terapia , Estenosis Coronaria/patología , Fibrinolíticos/farmacología , Infarto del Miocardio/patología , Infarto del Miocardio/terapia , Anciano , Angina de Pecho/tratamiento farmacológico , Angioplastia Coronaria con Balón , Aspirina/uso terapéutico , Angiografía Coronaria , Estenosis Coronaria/tratamiento farmacológico , Quimioterapia Combinada , Femenino , Fibrinolíticos/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/tratamiento farmacológico
15.
Heart Lung Circ ; 15(5): 291-6, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16860603

RESUMEN

BACKGROUND: Improved myocardial blush grade is associated with better MACE outcomes in acute myocardial infarction patients but there are no data on myocardial blush grade (MBG) assessment in unstable angina (UA) patients treated with coronary intervention. We sought to evaluate the use of angiographic MBG assessment in a cohort of UA patients treated with angioplasty. METHODS: Three hundred and seventy-two consecutive UA patients (mean age 68+/-1 years) treated with PCI were included. No patients had a pre-procedural troponin I (TnI) elevation. Final MBG was recorded for the territory subserving the PCI treated culprit lesion in each patient and graded 0 (no blush), 1 (minimal blush), 2 (moderate blush) and 3 (normal blush). TnI (normal range <0.1 microg/L) was measured 24h post-procedure. Patients who did not have a TnI elevation (i.e. <0.1 microg/L) were ascribed a value of 0.1 microg/L. Patients were followed up (mean 962+/-83 days) by postal questionnaire. RESULTS: Baseline risk factors were comparable between final MBG groups. There was no significant difference in mortality rate between groups. Post-procedural troponin I elevations were 0.34+/-0.12, 0.68+/-0.26, 0.14+/-0.01 and 0.11+/-0.01 for MBG groups 0, 1, 2 and 3 (p<0.001). Patients with minimal MBG underwent proportionately more target vessel revascularisation (p<0.05). CONCLUSIONS: Improved blush grade in UA patients undergoing PCI is associated with lower post-procedural TnI elevation. Identification of UA patients with poor final MBG may allow a window of opportunity for the administration of adjuvant therapies to improve microvascular perfusion in the future.


Asunto(s)
Angina Inestable/sangre , Angioplastia Coronaria con Balón/métodos , Miocardio/metabolismo , Troponina I/sangre , Anciano , Angina Inestable/diagnóstico por imagen , Angina Inestable/terapia , Biomarcadores/sangre , Angiografía Coronaria , Estudios de Seguimiento , Humanos , Pronóstico , Estudios Retrospectivos
16.
Pacing Clin Electrophysiol ; 28(8): 867-9, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16105017

RESUMEN

The finding of complete occlusion of the superior venal cava during the performance of cardiac pacing is rare. We report a case where performance of angioplasty aided the successful completion of permanent pacemaker implantation.


Asunto(s)
Angioplastia , Aleteo Atrial/terapia , Marcapaso Artificial , Síndrome de la Vena Cava Superior/terapia , Humanos , Masculino , Persona de Mediana Edad , Radiografía , Síndrome de la Vena Cava Superior/diagnóstico por imagen
17.
Proteomics ; 5(5): 1395-410, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15800873

RESUMEN

Brief periods of myocardial ischemia prior to timely reperfusion result in prolonged, yet reversible, contractile dysfunction of the myocardium, or "myocardial stunning". It has been hypothesized that the delayed recovery of contractile function in stunned myocardium reflects damage to one or a few key sarcomeric proteins. However, damage to such proteins does not explain observed physiological alterations to myocardial oxygen consumption and ATP requirements observed following myocardial stunning, and therefore the impact of alterations to additional functional groups is unresolved. We utilized two-dimensional gel electrophoresis and mass spectrometry to identify changes to the protein profiles in whole cell, cytosolic- and myofilament-enriched subcellular fractions from isolated, perfused rabbit hearts following 15 min or 60 min low-flow (1 mL/min) ischemia. Comparative gel analysis revealed 53 protein spot differences (> 1.5-fold difference in visible abundance) in reperfused myocardium. The majority of changes were observed to proteins from four functional groups: (i) the sarcomere and cytoskeleton, notably myosin light chain-2 and troponin C; (ii) redox regulation, in particular several components of the NADH ubiquinone oxidoreductase complex; (iii) energy metabolism, encompassing creatine kinase; and (iv) the stress response. Protein differences appeared to be the result of isoelectric point shifts most probably resulting from chemical modifications, and molecular mass shifts resulting from proteolytic or physical fragmentation. This is consistent with our hypothesis that the time course for the onset of injury associated with myocardial stunning is too brief to be mediated by large changes to gene/protein expression, but rather that more subtle, rapid and potentially transient changes are occurring to the proteome. The physical manifestation of stunned myocardium is therefore the likely result of the summed functional impairment resulting from these multiple changes, rather than a result of damage to a single key protein.


Asunto(s)
Proteínas Musculares/análisis , Miocardio/química , Miocardio/metabolismo , Proteoma/análisis , Proteómica , Daño por Reperfusión/metabolismo , Secuencia de Aminoácidos , Animales , Fraccionamiento Celular , Electroforesis en Gel Bidimensional , Hemodinámica , Humanos , Técnicas In Vitro , Masculino , Espectrometría de Masas , Datos de Secuencia Molecular , Aturdimiento Miocárdico/metabolismo , Oxidación-Reducción , Conejos
18.
Catheter Cardiovasc Interv ; 63(4): 474-81, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15558760

RESUMEN

The optimal treatment of bifurcation lesions remains controversial. We describe a new technique we term shunt stenting. This technique incorporates both the new technology of drug-eluting stents and a novel procedure for optimizing the ostial side branch stent positioning. To date, early angiographic and clinical follow-up have been encouraging.


Asunto(s)
Angioplastia Coronaria con Balón/métodos , Materiales Biocompatibles Revestidos/uso terapéutico , Enfermedad de la Arteria Coronaria/terapia , Inmunosupresores/uso terapéutico , Stents , Anciano , Implantación de Prótesis Vascular , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/metabolismo , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/etiología , Infarto del Miocardio/metabolismo , Estudios Prospectivos , Sirolimus/uso terapéutico , Stents/efectos adversos , Resultado del Tratamiento
19.
Catheter Cardiovasc Interv ; 59(4): 463-5, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12891607

RESUMEN

The rotablator burr rarely becomes trapped within calcified lesions. Manual traction can be ineffective and dangerous. We report a case that illustrates a novel technique involving use of a percutaneous snare in conjunction with partial disassembly of the rotablator device to remove a trapped burr without need for open surgical intervention.


Asunto(s)
Aterectomía Coronaria/instrumentación , Calcinosis/cirugía , Estenosis Coronaria/cirugía , Remoción de Dispositivos/métodos , Complicaciones Intraoperatorias/cirugía , Anciano , Falla de Equipo , Humanos , Masculino
20.
Proteomics ; 2(9): 1204-10, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12362337

RESUMEN

It has been hypothesised that activation of matrix metalloproteinase-2 (MMP-2) contributes to reversible myocardial dysfunction (stunning) following short-term ischaemia and reperfusion. Gelatin zymography was used to measure release of both pro-MMP-2 (72 kDa) and MMP-2 (62 kDa), into the coronary effluent from isolated, perfused rabbit hearts during 90 min aerobic perfusion (control), or low-flow ischaemia (15 or 60 min at 1 mL/min), followed by 60 min reperfusion. In controls, pro-MMP-2 was detected in the coronary effluent throughout the first 30 min of aerobic perfusion, but MMP-2 was not detected. In contrast, MMP-2 was detected in the coronary effluent during reperfusion after both 15 and 60 min ischaemia. However, while left ventricular systolic function was impaired after both 15 min and 60 min ischaemia, a significant increase in the release of MMP-2 was only detected in hearts following 60 min ischaemia. The dissociation between mechanical function and MMP-2 levels suggest that MMP-2 does not contribute to myocardial stunning in this model, but may contribute to myocardial dysfunction following prolonged ischaemia.


Asunto(s)
Isquemia , Metaloproteinasa 2 de la Matriz/metabolismo , Miocardio/enzimología , Animales , Activación Enzimática , Femenino , Hemodinámica , Masculino , Conejos , Reperfusión , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Tiempo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA