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1.
AJNR Am J Neuroradiol ; 41(7): 1251-1255, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32499246

RESUMEN

BACKGROUND AND PURPOSE: Cephaloceles are relatively rare conditions caused by a congenital and/or acquired skull defect. The incidence of associated venous brain anomalies with regard to cephaloceles remains to be fully elucidated. Accordingly, we sought to assess the prevalence of sigmoid sinus dehiscence and diverticula in patients with spontaneous skull base cephaloceles. MATERIALS AND METHODS: Our institutional data base was retrospectively queried from 2005 to 2018. Patients in whom spontaneous skull base cephaloceles were identified were ultimately included in the study cohort. These patients subsequently had their sigmoid sinuses re-evaluated with focused attention on the possible presence of dehiscence and/or diverticula. RESULTS: We identified 56 patients: 12 men and 44 women. After re-evaluation of the sigmoid sinuses, evidence of dehiscence and/or diverticula was noted in 21 patients. The right sigmoid sinus was involved in 11 patients, and the left sigmoid sinus was involved in 7 patients, including 3 cases of diverticulum. In 3 patients, evidence of bilateral sigmoid sinus dehiscence and diverticula was noted. Female sex was associated with sigmoid sinus dehiscence and diverticula by univariate analysis (P = .019). By linear regression, cephalocele volume was negatively associated with sigmoid sinus dehiscence and diverticula (coefficient, -2266, P value < .007, adjusted R 2 = 0.1077). By univariate logistic regression using average cephalocele volume as a cutoff, we demonstrate a statistically significant finding of lower volumes being associated with sigmoid sinus dehiscence and diverticula with an odds ratio of 3.58 (P = .05). CONCLUSIONS: The prevalence of sigmoid sinus dehiscence and diverticula in patients with cephalocele is high. Female sex is associated with sigmoid sinus dehiscence and diverticula. The cephalocele volume appears to be inversely proportional to sigmoid sinus dehiscence and diverticula.


Asunto(s)
Encefalopatías/epidemiología , Senos Craneales/patología , Encefalocele/complicaciones , Adulto , Encefalopatías/patología , Divertículo/epidemiología , Encefalocele/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos , Base del Cráneo
2.
Pediatr Cardiol ; 39(7): 1484-1488, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29948024

RESUMEN

Up to 10% of Fontan patients require pacemakers; an epicardial approach has historically been used. A transvenous approach can be used but carries risk of Fontan obstruction, thromboembolism, and can be technically challenging. The safety and efficacy of these approaches is not well described. The aim of this study was to compare epicardial and transvenous pacemaker outcomes in Fontan patients, specifically, device performance and adverse event rate. A retrospective review was performed on Fontan pacemaker patients followed at a single institution. Thirty-one Fontan pacemaker patients were identified between 1985 and 2017. Twenty-six had an epicardial system, five transvenous, and three converted from epicardial to transvenous. Average atrial lead sensing at placement was 3.23 versus 2.35 mV (p = 0.52) for epicardial and transvenous leads, respectively. Median atrial and ventricular lead longevity was 86.4 versus 98.8 months (p = 0.56) and 73.2 versus 140 months (p = 0.3) with generator longevity of 65.5 versus 73.9 (p = 0.16) months for epicardial versus transvenous systems, respectively. One major complication occurred in a transvenous patient, and two minor complications occurred in epicardial patients. All transvenous patients received warfarin except one, who converted to dabigatran. Epicardial patients received aspirin (n = 20), warfarin (n = 3) or a warfarin/aspirin combination (n = 3). No thromboembolic events occurred. System revision was required in 13 epicardial and 5 transvenous patients. There were two deaths, none related to the pacemaker system. Transvenous pacemakers can be utilized with equal efficacy compared to epicardial pacemakers with trends toward longer lead longevity in transvenous pacemaker systems.


Asunto(s)
Estimulación Cardíaca Artificial/métodos , Procedimiento de Fontan/métodos , Marcapaso Artificial/efectos adversos , Adulto , Estimulación Cardíaca Artificial/efectos adversos , Falla de Equipo/estadística & datos numéricos , Femenino , Procedimiento de Fontan/efectos adversos , Atrios Cardíacos/fisiopatología , Cardiopatías Congénitas/cirugía , Ventrículos Cardíacos/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Pericardio/cirugía , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos
3.
J Am Soc Echocardiogr ; 14(9): 917-20, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11547278

RESUMEN

Previous studies of intravenous contrast agents have excluded patients in the intensive care unit. These patients remain among the most technically difficult to image with ultrasound. We studied the effect of different imaging modalities with and without intravenous contrast (Optison) on endocardial border visualization during echocardiography. Fifty patients in the intensive care unit (32 men, 24 on mechanical ventilator, 10 with chest bandages; mean age, 59 years; mean weight, 91.7 kg; mean height, 67.6 inches) were considered to have technically difficult images when the endocardium could not be visualized in at least 2 of the 6 segments in either apical view. Each patient was studied with the use of fundamental (F), harmonic (H), fundamental + Optison (F + O), and H + O techniques, with standard long-axis, short-axis, and apical 4- and 2-chamber views. Intravenous Optison (0.5 to 1.5 mL) was given before F + O and H + O imaging. There were no contrast-related side effects noted. All images were stored digitally in a quad-screen format. For each set of images, segments (n = 22) were given an endocardial border visualization score of 0 if not visualized, 1 if visualized in either systole or diastole, and 2 if visualized in both. There was stepwise improvement in endocardial border visualization, with mean endocardial border visualization score of 1.09 +/- 0.83 (F), 1.33 +/- 0.81 (H), 1.64 +/- 0.62 (F + O), and 1.90 +/- 0.35 (H + O). There was a statistically significant difference between each group (P <.001). The incremental benefit of Optison was greater with harmonic imaging than with fundamental (P <.001). The use of Optison is safe and effective in the intensive care unit. In combination with harmonic imaging, contrast provides maximal endocardial border delineation during echocardiographic imaging of technically difficult patients in the intensive care unit.


Asunto(s)
Albúminas , Ecocardiografía/métodos , Endocardio/diagnóstico por imagen , Fluorocarburos , Albúminas/administración & dosificación , Medios de Contraste/administración & dosificación , Femenino , Fluorocarburos/administración & dosificación , Humanos , Inyecciones Intravenosas , Unidades de Cuidados Intensivos , Masculino , Microesferas , Persona de Mediana Edad , Ultrasonido
4.
J Am Coll Cardiol ; 37(5): 1422-9, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11300456

RESUMEN

OBJECTIVES: We evaluated whether two-dimensional high-resolution transthoracic echocardiography (HR-2DTTE) can detect changes in arterial wall thickness and size associated with subclinical coronary artery disease (CAD). BACKGROUND: Arterial wall thickening, compensatory arterial enlargement and a preserved arterial lumen characterize subclinical atherosclerosis. Detection of these changes during the asymptomatic stage of CAD may allow early treatment and prevention of acute coronary events. METHODS: Twenty-six patients with angiographically proven CAD and 29 normal volunteers underwent HR-2DTTE evaluation of the left anterior descending coronary artery (LAD) using an ATL 5000 echograph (Advanced Technology Laboratories, Bothell, Washington) with a 4 to 7 MHz transducer. Significant (>70%) LAD stenosis was present in 15 patients (mean 82%); 11 patients did not have significant LAD stenosis (mean 26%) and represented a surrogate for subclinical LAD disease. Wall thickness, maximal luminal diameter and external diameter of the LAD were measured. RESULTS: Left anterior descending coronary artery wall thickness was larger in patients (1.9 +/- 0.4 mm) than it was in volunteers (0.9 +/- 0.1 mm, p < 0.001). The external diameter of the LAD was (6.0 +/- 1.1 mm) in patients and (3.9 +/- 0.7 mm) in volunteers (p < 0.001). Luminal diameter was 2.2 +/- 0.5 mm in patients and 2.1 +/- 0.6 mm in volunteers (p = NS). There was no difference in wall thickness (1.9 +/- 0.4 mm vs. 2.0 +/- 0.4 mm), luminal diameter (2.2 +/- 0.5 mm vs. 2.2 +/- 0.4 mm) and external diameter (5.9 +/- 1.0 mm vs. 6.2 +/- 1.2 mm) between the patients with <70% and >70% LAD stenosis. CONCLUSIONS: Left anterior descending coronary artery wall thickness and external diameter are significantly increased in patients with CAD as compared with normal subjects, and HR-2DTTE is sensitive enough to detect these differences. Wall thickness and external diameter are increased to the same extent in patients with obstructive and subclinical LAD disease.


Asunto(s)
Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Ecocardiografía , Aumento de la Imagen , Adulto , Anciano , Anciano de 80 o más Años , Vasos Coronarios/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad
5.
J Am Soc Echocardiogr ; 14(2): 138-48, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11174448

RESUMEN

At low doses, dobutamine has potent inotropic, but limited chronotropic, effects-properties that may be necessary for detection of hibernating myocardium. The efficacy of other catecholamines, which have more closely coupled inotropic and chronotropic effects, for the detection of viable myocardium is unknown. This study evaluated the efficacy of arbutamine, a catecholamine with potent chrono-tropic effects, for the detection of viable myocardium in a canine model of hibernating myocardium. Contractile reserve was assessed during stepwise arbutamine infusion (dosages of 2.5, 5, 10, 50, and 100 ng/kg/min) at 3 days (early) and 4 weeks (late) after coronary ligation. Segment shortening, wall thickening, and segmental wall motion were assessed by sonomicrometry and echocardiography. After 4 weeks of occlusion, functional recovery was assessed after revascularization. During the early arbutamine study, the sensitivity for predicting functional recovery was highest at a dosage of 50 ng/kg/min, which also produced tachycardia. The sensitivity was 50% for segment shortening, 20% for wall thickening, and 75% for wall motion score. The late arbutamine study had improved sensitivity. The sensitivity was 100% for segment shortening, 80% for wall thickening, and 90% for wall motion score at a dosage of 50 ng/kg/min. At the late arbutamine study, myocardial perfusion reserve in the ischemic zone of dogs with functional recovery was only mildly reduced (2.0 versus 2.6 in nonischemic zones, P =.53). After coronary occlusion, viable myocardium can be detected with high doses of arbutamine that produce tachycardia. However, the sensitivity of arbutamine stimulation for predicting functional recovery is low early after occlusion, but it is improved by 4 weeks after occlusion with adequate perfusion reserve.


Asunto(s)
Cardiotónicos , Catecolaminas , Aturdimiento Miocárdico/diagnóstico , Animales , Enfermedad Crónica , Modelos Animales de Enfermedad , Perros , Hemodinámica , Contracción Miocárdica/efectos de los fármacos , Aturdimiento Miocárdico/diagnóstico por imagen , Flujo Sanguíneo Regional , Sensibilidad y Especificidad , Ultrasonografía , Disfunción Ventricular Izquierda/diagnóstico
6.
J Am Soc Echocardiogr ; 12(9): 714-9, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10477415

RESUMEN

Conventional echocardiograms are typically recorded on videotape and later reviewed and interpreted by a physician. Although videotape recording is an excellent medium for this purpose, it does have several disadvantages, which may be overcome by digital storage. This study compared the diagnostic accuracy of digitized and videotape recorded echocardiograms. Echocardiographic examinations (n = 110) were recorded simulta-neously on videotape and were digitized with a commercially available frame grabber system. Images were transmitted by an Ethernet link to the network-based computer system and compressed with a nondestructive compression algorithm. Images were reviewed on a personal computer. Images were interpreted by 3 observers, and differences in interpretation were documented. There were 274 findings in 110 patients. Exact agreement in interpretation was found in 83%. A major discrepancy occurred in 2%, and a minor discrepancy occurred in 15%. Most discrepancies occurred in the setting of valvular heart disease. When compared with a consensus interpretation, no significant difference was seen in the number of errors between the digital and videotape interpretation. We conclude that the interpretation of a properly recorded digitized echocardiographic examination yields interpretations equivalent to those of videotape recordings.


Asunto(s)
Ecocardiografía , Interpretación de Imagen Asistida por Computador , Grabación de Cinta de Video , Humanos , Variaciones Dependientes del Observador , Proyectos Piloto , Estudios Prospectivos
7.
J Am Soc Echocardiogr ; 12(7): 559-63, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10398914

RESUMEN

The diagnostic value of echocardiography hinges on the reader's ability to adequately visualize the endocardium of the left ventricle. This study was designed to evaluate the potential benefit of noncontrast harmonic imaging to enhance endocardial visualization. Eighty consecutive outpatients who underwent treadmill stress echocardiography were randomly assigned to either fundamental or harmonic imaging. The echoes were interpreted by 2 experienced readers. Compared with fundamental imaging, harmonic imaging of tissue improved the overall endocardial visualization score by 35% and 21% for readers 1 and 2, respectively (P <.001). Harmonic imaging also reduced the percentage of nondiagnostic segments by one half (P <.01). In patients undergoing treadmill stress echo, harmonic imaging offers a clinically significant improvement in endocardial visualization.


Asunto(s)
Ecocardiografía/métodos , Cardiopatías/diagnóstico por imagen , Endocardio/diagnóstico por imagen , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Función Ventricular Izquierda
8.
Am J Cardiol ; 82(11): 1434-6, A9, 1998 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-9856935

RESUMEN

The location of left anterior descending arterial stents was documented in 10 of 13 patients using 3-dimensionally acquired, 2-dimensionally displayed transthoracic echocardiography. The echocardiographic appearance of stents was characterized, and the location of the proximal and mid-left anterior descending artery was objectively documented.


Asunto(s)
Enfermedad Coronaria/diagnóstico por imagen , Ecocardiografía Doppler , Ecocardiografía Tridimensional , Stents , Adulto , Anciano , Ecocardiografía Transesofágica , Humanos , Persona de Mediana Edad
9.
J Am Soc Echocardiogr ; 11(10): 989-91, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9804107

RESUMEN

Power motion imaging allows interrogation of low-velocity tissue. By means of power motion imaging with 2 different late-model echographs we identified an intra-atrial tumor that was undetectable on conventional transthoracic echocardiograms.


Asunto(s)
Neoplasias Cardíacas/diagnóstico por imagen , Linfoma de Células B Grandes Difuso/diagnóstico por imagen , Anciano , Ecocardiografía Transesofágica , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Estudios Retrospectivos
10.
J Am Coll Cardiol ; 32(3): 746-52, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9741522

RESUMEN

OBJECTIVES: The echocardiographic contrast-enhancing effects and safety profile of ALBUNEX (a suspension of air-filled albumin microspheres) were compared with the new contrast agent OPTISON (formerly FS069: a suspension of albumin microspheres containing the gas perfluoropropane) in 203 patients with inadequate noncontrast echocardiograms. BACKGROUND: The efficacy of ALBUNEX has been limited by its short duration of action. By using perfluoropropane instead of air within the microsphere, its duration of action is increased. METHODS: Each patient received ALBUNEX (0.8 and 0.22 mL/kg) and OPTISON (0.2, 0.5, 3.0, and 5.0 mL) on separate days a minimum of 48 hours apart. Echocardiograms were evaluated for increase in left ventricular (LV) endocardial border length, degree of LV opacification, number of LV endocardial border segments visualized, conversion from a nondiagnostic to a diagnostic echocardiogram, and duration of contrast enhancement. A thorough safety evaluation was conducted. RESULTS: Compared with ALBUNEX, OPTISON more significantly improved every measure of contrast enhancement. OPTISON increased well-visualized LV endocardial border length by 6.0+/-5.1, 6.9+/-5.4, 7.5+/-4.7, and 7.6+/-4.8 cm, respectively, for each of the four doses, compared with only 2.2+/-4.5 and 3.4+/-4.6 cm, respectively, for the two ALBUNEX doses (p < 0.001). 100% LV opacification was achieved in 61%, 73%, 87%, and 87% of the patients with the four doses of OPTISON, but in only 16% and 36% of the patients with the two ALBUNEX doses (p < 0.001). Conversion of nondiagnostic to diagnostic echocardiograms with contrast occurred in 74% of patients with the optimal dose of OPTISON (3.0 mL) compared with only 26% with the optimal dose of ALBUNEX (0.22 mL/kg) (p < 0.001). The duration of contrast effect was also significantly greater with OPTISON than with ALBUNEX. In a subset of patients with potentially poor transpulmonary transit of contrast (patients with chronic lung disease or dilated cardiomyopathy), OPTISON more significantly improved the same measures of contrast enhancement compared with ALBUNEX and did so to the same extent as in the overall population. Side effects were similar and transient with the two agents. CONCLUSION: OPTISON appears to be a safe, well-tolerated echocardiographic contrast agent that is superior to ALBUNEX.


Asunto(s)
Albúminas , Medios de Contraste , Ecocardiografía , Endocardio/diagnóstico por imagen , Fluorocarburos , Ventrículos Cardíacos/diagnóstico por imagen , Función Ventricular Izquierda/fisiología , Cardiomiopatía Dilatada/diagnóstico por imagen , Cardiomiopatía Dilatada/fisiopatología , Relación Dosis-Respuesta a Droga , Endocardio/fisiopatología , Ventrículos Cardíacos/fisiopatología , Humanos , Aumento de la Imagen , Enfermedades Pulmonares Obstructivas/diagnóstico por imagen , Enfermedades Pulmonares Obstructivas/fisiopatología , Estudios Prospectivos , Sensibilidad y Especificidad , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/fisiopatología
11.
Arch Intern Med ; 158(13): 1450-3, 1998 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-9665355

RESUMEN

BACKGROUND: While numerous studies suggest that African Americans receive fewer invasive cardiac procedures than whites, the basis for these treatment differences is not understood. METHODS: We conducted focus group sessions with patients who had received treatment in the hospital or the emergency department within the preceding 3 months for ischemic heart disease at 2 urban, university-affiliated hospitals. RESULTS: Discussions with patients identified the following factors that influenced their decision making: clarity, simplicity, and consistency of treatment recommendations; advice from friends and family about whether to accept recommendations; availability to speak with others who accepted similar recommendations; and having honest and caring physicians. African American patients identified the following additional factors that influenced their decision making: perceptions of health care discrimination; perceptions of undesirable physician behavior; faith in God to control one's destiny; and patient-physician camaraderie. CONCLUSIONS: Participants identified common issues influencing health care decision making, regardless of race. However, additional factors were expressed only by African American participants. These factors conveyed racial differences in perceptions of the health care system that may, in part, contribute to differences in health care decision making and treatment.


Asunto(s)
Negro o Afroamericano/estadística & datos numéricos , Toma de Decisiones , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/etnología , Confianza , Población Blanca/estadística & datos numéricos , Comprensión , Femenino , Grupos Focales , Humanos , Masculino , Investigación Cualitativa , Investigación , Estados Unidos
12.
J Am Coll Cardiol ; 32(1): 230-6, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9669275

RESUMEN

OBJECTIVES: This study was performed to compare the safety and efficacy of intravenous 2% dodecafluoropentane (DDFP) emulsion (EchoGen) with that of active control (sonicated human albumin [Albunex]) for left ventricular (LV) cavity opacification in adult patients with a suboptimal echocardiogram. BACKGROUND: The development of new fluorocarbon-based echocardiographic contrast agents such as DDFP has allowed opacification of the left ventricle after peripheral venous injection. We hypothesized that DDFP was clinically superior to the Food and Drug Administration-approved active control. METHODS: This was a Phase III, multicenter, single-blind, active controlled trial. Sequential intravenous injections of active control and DDFP were given 30 min apart to 254 patients with a suboptimal echocardiogram, defined as one in which the endocardial borders were not visible in at least two segments in either the apical two- or four-chamber views. Studies were interpreted in blinded manner by two readers and the investigators. RESULTS: Full or intermediate LV cavity opacification was more frequently observed after DDFP than after active control (78% vs. 31% for reader A; 69% vs. 34% for reader B; 83% vs. 55% for the investigators, p < 0.0001). LV cavity opacification scores were higher with DDFP (2.0 to 2.5 vs. 1.1 to 1.5, p < 0.0001). Endocardial border delineation was improved by DDFP in 88% of patients versus 45% with active control (p < 0.001). Similar improvement was seen for duration of contrast effect, salvage of suboptimal echocardiograms, diagnostic confidence and potential to affect patient management. There was no difference between agents in the number of patients with adverse events attributed to the test agent (9% for DDFP vs. 6% for active control, p = 0.92). CONCLUSIONS: This Phase III multicenter trial demonstrates that DDFP is superior to sonicated human albumin for LV cavity opacification, endocardial border definition, duration of effect, salvage of suboptimal echocardiograms, diagnostic confidence and potential to influence patient management. The two agents had similar safety profiles.


Asunto(s)
Medios de Contraste , Ecocardiografía , Fluorocarburos , Cardiopatías/diagnóstico por imagen , Adulto , Anciano , Emulsiones , Endocardio/diagnóstico por imagen , Femenino , Ventrículos Cardíacos/diagnóstico por imagen , Humanos , Inyecciones Intravenosas , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Método Simple Ciego
13.
Soc Sci Med ; 46(7): 929-33, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9541078

RESUMEN

Focus groups are increasingly being used to provide insights to researchers and policy makers. These data complement quantitative approaches to understanding the world. Unfortunately, quantitative and qualitative methodologies have often been viewed as antithetical, rather than complementary, strategies. While focus groups can clearly generate rich information that is unobtainable through other quantitative methods, it is important to determine the degree to which different raters can consistently extract information from transcripts. Thus, our goal was to quantify agreement in the interpretation of transcripts from patient and physician focus groups, using decision-making in ischemic heart disease as a model. We used data from focus groups with both patients and physicians that sought to identify factors affecting diagnostic and treatment decisions in ischemic heart disease. Three raters independently reviewed transcribed audiotapes from focus groups of patients with ischemic heart disease, as well as focus groups of physicians who care for these patients. We found that raters could not distinguish between major and minor factors reliably. More troubling, however, is that consistency regarding the apparently straightforward judgment as to the mere presence or absence of a factor was difficult to achieve. In particular, the three raters of each transcript failed to agree on between one third and one half of the factors. This reasonably high level of disagreement occurred despite the raters: (1) having generated the individual factors themselves based upon their reading a random sample of actual transcripts and (2) being trained in the use of rating forms (including standard definitions of themes). These data suggest that if a single rater evaluates focus group transcripts, as is commonly done, judgments may not be reproducible by other raters. Moreover, a single rater may not extract all important information contained in the transcripts.


Asunto(s)
Grupos Focales , Isquemia Miocárdica , Femenino , Humanos , Masculino , Variaciones Dependientes del Observador
14.
Am Heart J ; 135(2 Pt 1): 253-60, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9489973

RESUMEN

We investigated the clinical utility of cardiac troponin T (TnT) and echocardiography in the emergency department to predict subsequent in-hospital diagnosis and adverse cardiac events. TnT is a cardiac-specific protein released during cell injury such as that following acute myocardial inFarction (MI). Unlike creatine kinase-MB isoenzymes, TnT is increased in a subset of patients with unstable angina, and these may be at higher risk for subsequent cardiac events. Echocardiography is a useful noninvasive imaging technique for the assessment of ischemic heart disease in acute care settings because of its mobility and rapid results. Serial TnT determinations and echocardiographic images were prospectively evaluated in 100 patients with chest discomfort and admitted to the hospital. Serum was obtained for CKMB and TnT on presentation to the emergency department and 4, 8, 16 and 24 hours later. TnT was considered increased when at values greater than 0.1 microg/L. Echocardiograms were recorded on videotape in the emergency department and images reviewed in a blinded fashion for wall-motion abnormalities. When available, current echocardiographic results were compared with previous results to determine whether a new wall-motion abnormality was present. Of the 100 patients (57 men, 43 women), TnT was increased in 21 of 21 with acute MI and 15 of 41 with unstable angina. One of the 38 patients with stable angina had an increased TnT value and died 5 months later of a noncardiac cause. Ninety percent of patients who sustained acute MI had a TnT increase detected within 4 hours of presentation. Fifteen of 18 patients with acute MI and 9 of 37 patients with unstable angina had a new wall-motion abnormality on echocardiography. The combination of TnT levels with echocardiography yielded a positive predictive value of 84% and a negative predictive value of 90% for adverse cardiac events in the follow-up population, which was more accurate than either test analyzed separately. TnT and echocardiography are useful tests in emergency department triage of unstable coronary syndromes. Both tests are predictive of discharge diagnosis and follow-up events. However, the combined utility of TnT levels and echocardiographic imaging is a more powerful predictor of adverse cardiac events than isolated results.


Asunto(s)
Angina Inestable/diagnóstico , Ecocardiografía , Infarto del Miocardio/diagnóstico , Troponina/sangre , Angina Inestable/epidemiología , Biomarcadores/sangre , Creatina Quinasa/sangre , Electrocardiografía , Servicio de Urgencia en Hospital , Femenino , Humanos , Isoenzimas , Masculino , Persona de Mediana Edad , Infarto del Miocardio/epidemiología , Valor Predictivo de las Pruebas , Estudios Prospectivos , Factores de Tiempo , Triaje , Troponina T , Grabación de Cinta de Video
15.
J Am Coll Cardiol ; 30(7): 1707-13, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9385897

RESUMEN

OBJECTIVES: We sought to identify the clinical characteristics associated with, and to investigate the impact of cohort selection criteria on, interracial use of invasive cardiac procedures and to determine survival. BACKGROUND: Although interracial differences in the use of invasive cardiac procedures have been previously reported, the underlying reasons are not known. METHODS: A retrospective cohort study was conducted at a Veterans Affairs Medical Center. Study patients were evaluated for cardiovascular disease between January 1 and December 31, 1993. RESULTS: The study included 1,406 male patients (85% white, 58% married), with a mean age of 63.4 years. African Americans were less likely than whites to undergo procedures (cardiac catheterization: odds ratio [OR] 0.37, 95% confidence interval [CI] 0.24 to 0.58; coronary angioplasty: OR 0.60, 95% CI 0.25 to 1.49; coronary bypass surgery: OR 0.22, 95% CI 0.08 to 0.63; any procedure: OR 0.32, 95% CI 0.21 to 0.50). On bivariate analysis, patients who underwent cardiac procedures were more likely to be younger, married and reside nonlocally and less likely to have severe comorbid disease; however, African Americans were less likely to be married and to reside nonlocally and more likely to have severe comorbid disease. Cohorts adjusting for referral status and specified cardiac diagnoses reduced or reversed interracial treatment differences. Thirty-day and 1-year survival rates (96% and 87.6%, respectively) were equivalent. CONCLUSIONS: Racial disparity in invasive cardiac procedure use may be partially explained by clinical differences and cohort selection bias. Despite treatment differences, survival rates were equivalent in African Americans and whites.


Asunto(s)
Angioplastia Coronaria con Balón/estadística & datos numéricos , Negro o Afroamericano/estadística & datos numéricos , Cateterismo Cardíaco/estadística & datos numéricos , Puente de Arteria Coronaria/estadística & datos numéricos , Isquemia Miocárdica/etnología , Isquemia Miocárdica/terapia , Estudios de Cohortes , Comorbilidad , Hospitales de Veteranos/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/mortalidad , Evaluación de Procesos y Resultados en Atención de Salud , Estudios Retrospectivos , Sesgo de Selección , Tasa de Supervivencia , Población Blanca/estadística & datos numéricos
16.
J Am Coll Cardiol ; 29(1): 55-61, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8996295

RESUMEN

OBJECTIVES: We investigated the patterns of perfusion and metabolism in dysfunctional myocardium whose contractility improved with dobutamine. BACKGROUND: Clinical studies have suggested that dobutamine echocardiography can identify hibernating myocardium, but laboratory studies suggest that reduced perfusion limits the response to dobutamine. METHODS: Twenty-five patients with coronary disease and ventricular dysfunction underwent low (5 and 10 micrograms/kg body weight per min) and high dose (maximum of 50 micrograms/kg per min) dobutamine echocardiography and positron emission tomography (PET) using nitrogen-13 (N-13) ammonia and fluorine-18 fluorodeoxyglucose (FDG) for imaging of perfusion and metabolism. Wall motion and tracer uptake were scored in 16 left ventricular segments. RESULTS: Perfusion and metabolism were normal in 56.4%, mildly reduced in 29.1% and mismatched (reduced perfusion, preserved FDG uptake) in 14.5% of dysfunctional segments viable on PET. Wall motion improved with dobutamine in 89 dysfunctional segments (62 at low dose, 27 only at peak dose), and 86 of these (97%) were viable on PET. Improvement in wall motion with dobutamine was more common in segments with normal perfusion and metabolism (56.5%) than in those with mildly reduced tracer uptake (28.5%, p < 0.001) and those with mismatch (32%, p = 0.03). All the segments with a biphasic response were supplied by vessels with > or = 70% stenosis, and 88% had normal perfusion and metabolism. CONCLUSIONS: The majority of viable segments with rest dysfunction had normal perfusion and metabolism, suggesting that myocardial stunning was common. Improvement of wall motion at low and high doses of dobutamine was highly correlated with myocardial viability on PET and was more common in myocardium with normal perfusion. A biphasic response to dobutamine identified segments with normal perfusion and metabolism supplied by severely diseased vessels.


Asunto(s)
Dobutamina , Ecocardiografía/métodos , Aturdimiento Miocárdico/diagnóstico , Tomografía Computarizada de Emisión , Amoníaco , Angiografía Coronaria , Desoxiglucosa/análogos & derivados , Estudios de Evaluación como Asunto , Femenino , Radioisótopos de Flúor , Fluorodesoxiglucosa F18 , Corazón/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Contracción Miocárdica/efectos de los fármacos , Aturdimiento Miocárdico/metabolismo , Aturdimiento Miocárdico/fisiopatología , Miocardio/metabolismo , Radioisótopos de Nitrógeno
17.
Clin Cardiol ; 19(8): 607-12, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8864333

RESUMEN

Determining the presence of viable myocardium has prognostic and therapeutic implications in the treatment of ischemic heart disease. Dobutamine stress echocardiography (DSE) is one possible technique to help identify both hibernating and stunned but viable myocardium. Low-dose dobutamine infusion has an increased inotropic effect, while higher doses cause both inotropic and chronotropic effects. Thus, at lower doses cardiac augmentation occurs, and at higher doses regions of ischemia may be produced in the presence of significant coronary artery disease. This is manifested echocardiographically as changes in segmental wall motion. In theory, therefore, areas of viable myocardium should show improved wall motion at low doses, and areas of irreversible myocardial damage will remain akinetic. Five studies have investigated DSE for determining viability in the setting of acute myocardial infarction, thus looking for stunned but viable myocardium. DSE was shown to compare favorably with positron emission tomography and was highly sensitive and specific for predicting functional myocardial recovery. Five additional studies examined DSE for determining the presence of hibernating myocardium. The sensitivity and specificity of DSE were found to range from 71 to 92% and from 73 to 93%, respectively. The benefits of DSE include lower cost, convenience to both patient and physician, additional ancillary information, and determination of the possible need for urgent revascularization. Limitations of DSE include occasional technical difficulty in obtaining and interpreting studies and the need for larger volumes of viable myocardium to detect changes predictive of functional recovery. Larger trials are currently underway to confirm DSE as a reliable technique for determining myocardial viability.


Asunto(s)
Dobutamina/uso terapéutico , Ecocardiografía/métodos , Aturdimiento Miocárdico/diagnóstico por imagen , Humanos , Isquemia Miocárdica/diagnóstico por imagen , Sensibilidad y Especificidad
18.
J Am Soc Echocardiogr ; 9(4): 501-7, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8827633

RESUMEN

We prospectively compared digital echocardiographic images, by a minimal digital-acquisition strategy, with videotape images to determine the diagnostic utility of digital imaging in patients admitted to the emergency department with chest pain. Digital acquisition has many potential advantages for evaluating echocardiographic images, especially in the acute-care setting. It is not yet known how much the imaging study can be condensed with digital technology and still provide the necessary information needed for clinical echocardiographic diagnosis. One hundred seventeen patients with diagnoses consisting of coronary artery disease, pericardial disease, and valvular disease were studied. Overall agreement between videotape and digital recordings with regard to normal versus abnormal wall motion was 94% (p < 0.001). The wall motion score index, a semiquantitative measure of global function, also correlated well (r = 0.94). Complete concordance was noted in all patients with aortic stenosis and pericardial effusion. Digital echocardiographic imaging, by a minimal-acquisition strategy, is an accurate summary of the complete echocardiographic examination and provides the relevant diagnostic data needed for the assessment of patients with chest pain in the emergency department.


Asunto(s)
Dolor en el Pecho/diagnóstico por imagen , Ecocardiografía/métodos , Procesamiento de Imagen Asistido por Computador , Procesamiento de Señales Asistido por Computador , Grabación de Cinta de Video , Servicio de Urgencia en Hospital , Femenino , Cardiopatías/diagnóstico por imagen , Enfermedades de las Válvulas Cardíacas/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Pericardio
19.
Am J Cardiol ; 77(2): 175-9, 1996 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-8546087

RESUMEN

The purpose of this study was to examine the ability of dobutamine stress echocardiography to stratify patients with juvenile onset, insulin-dependent diabetes mellitus who are being considered for kidney and/or pancreas transplantation, into high-or low-risk groups for future cardiac events. Fifty-three such patients underwent dobutamine stress echocardiography before kidney and/or pancreas transplantation. Cardiac events, including cardiac death, nonfatal myocardial infarction, unstable angina, pulmonary edema, and need for coronary revascularization, occurring between the time of the dobutamine stress echocardiogram and the last patient follow-up contact were retrospectively identified. Twenty patients 938%) had an abnormal dobutamine stress echocardiogram. Eleven patients had 15 cardiac events over a mean (+/- SD) follow-up period of 418 +/- 269 days. Event rates were 45% among those with an abnormal, versus 6% among those with a normal dobutamine stress echocardiogram (p = 0.002). The result of the dobutamine stress test independently predicted prognosis in a multivariate analysis (p = 0.003, odds ratio = 12.7). We conclude that dobutamine stress echocardiography accurately stratifies patients with juvenile onset, insulin-dependent diabetes being considered for kidney and/or pancreas transplantation for risk of future cardiac events.


Asunto(s)
Diabetes Mellitus Tipo 1/diagnóstico por imagen , Dobutamina , Ecocardiografía , Cardiopatías/diagnóstico por imagen , Trasplante de Riñón , Trasplante de Páncreas , Adulto , Factores de Confusión Epidemiológicos , Angiografía Coronaria , Ecocardiografía/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Valor Predictivo de las Pruebas , Riesgo
20.
J Am Coll Cardiol ; 26(5): 1348-55, 1995 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-7594053

RESUMEN

OBJECTIVES: The purpose of this study was to 1) develop an animal model of hibernating myocardium, and 2) evaluate the ability of dobutamine stimulation to detect hibernating myocardium using both qualitative and quantitative assessment of regional myocardial function. BACKGROUND: Left ventricular dysfunction may be due to chronic ischemia with or without myocardial infarction and may improve after coronary blood flow is enhanced by revascularization procedures. This condition has been coined "hibernating myocardium" and variably defined in recent years. The results of recent clinical studies suggest that dobutamine echocardiography may be useful for detecting viable myocardium in patients with left ventricular dysfunction. METHODS: Twenty-one dogs underwent initial operation. Sonomicrometer crystals were implanted, and baseline measurements of segment shortening and wall thickening (by echocardiography) were made. A coronary artery was ligated; the chest was closed; and measurements were repeated. Dobutamine was incrementally infused with determination of wall thickening and segment shortening at baseline and on days 3 and 7 and weeks 2 and 4 after coronary artery occlusion. Finally, the chest was reopened; the ligated vessel was bypassed; and measurements were repeated. RESULTS: Of the 10 dogs that completed the entire protocol, 7 had varying degrees of nontransmural myocardial infarction (group 1), and 3 had complete transmural myocardial infarction (group 2). In group 1, baseline function was significantly impaired compared with preligation function but increased during dobutamine infusion. When reperfused after 4 weeks, both wall thickening and segment shortening increased significantly. In group 2, significant changes were not seen during the dobutamine studies or after reperfusion. Myocardial perfusion during dobutamine infusion increased in group 1 but did not change in group 2. CONCLUSIONS: We demonstrated improvement in chronically dysfunctional myocardium after restoration of previously interrupted myocardial blood flow in dogs after nontransmural myocardial infarction, thus validating a canine model of hibernating myocardium. As assessed by two independent methods, dobutamine infusion identified hibernating myocardium in an animal model.


Asunto(s)
Dobutamina , Isquemia Miocárdica/diagnóstico , Animales , Modelos Animales de Enfermedad , Dobutamina/administración & dosificación , Perros , Ecocardiografía , Función Ventricular Izquierda
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