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4.
J Nucl Cardiol ; 21(1): 192-220, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24374980

RESUMEN

The American College of Cardiology Foundation along with key specialty and subspecialty societies, conducted an appropriate use review of common clinical presentations for stable ischemic heart disease (SIHD) to consider use of stress testing and anatomic diagnostic procedures. This document reflects an updating of the prior Appropriate Use Criteria (AUC) published for radionuclide imaging (RNI), stress echocardiography (Echo), calcium scoring, coronary computed tomography angiography (CCTA), stress cardiac magnetic resonance (CMR), and invasive coronary angiography for SIHD. This is in keeping with the commitment to revise and refine the AUC on a frequent basis. A major innovation in this document is the rating of tests side by side for the same indication. The side-by-side rating removes any concerns about differences in indication or interpretation stemming from prior use of separate documents for each test. However, the ratings were explicitly not competitive rankings due to the limited availability of comparative evidence, patient variability, and range of capabilities available in any given local setting. The indications for this review are limited to the detection and risk assessment of SIHD and were drawn from common applications or anticipated uses, as well as from current clinical practice guidelines. Eighty clinical scenarios were developed by a writing committee and scored by a separate rating panel on a scale of 1-9, to designate Appropriate, May Be Appropriate, or Rarely Appropriate use following a modified Delphi process following the recently updated AUC development methodology. The use of some modalities of testing in the initial evaluation of patients with symptoms representing ischemic equivalents, newly diagnosed heart failure, arrhythmias, and syncope was generally found to be Appropriate or May Be Appropriate, except in cases where low pre-test probability or low risk limited the benefit of most testing except exercise electrocardiogram (ECG). Testing for the evaluation of new or worsening symptoms following a prior test or procedure was found to be Appropriate. In addition, testing was found to be Appropriate or May Be Appropriate for patients within 90 days of an abnormal or uncertain prior result. Pre-operative testing was rated Appropriate or May Be Appropriate only for patients who had poor functional capacity and were undergoing vascular or intermediate risk surgery with 1 or more clinical risk factors or an organ transplant. The exercise ECG was suggested as an Appropriate test for cardiac rehabilitation clearance or for exercise prescription purposes. Testing in asymptomatic patients was generally found to be Rarely Appropriate, except for calcium scoring and exercise testing in intermediate and high-risk individuals and either stress or anatomic imaging in higher-risk individuals, which were all rated as May Be Appropriate. All modalities of follow-up testing after a prior test or percutaneous coronary intervention (PCI) within 2 years and within 5 years after coronary artery bypass graft (CABG) in the absence of new symptoms were rated Rarely Appropriate. Pre-operative testing for patients with good functional capacity, prior normal testing within 1 year, or prior to low-risk surgery also were found to be Rarely Appropriate. Imaging for an exercise prescription or prior to the initiation of cardiac rehabilitation was Rarely Appropriate except for cardiac rehabilitation clearance for heart failure patients.


Asunto(s)
Cardiología/normas , Angiografía Coronaria/normas , Isquemia Miocárdica/terapia , Adulto , Anciano , Algoritmos , American Heart Association , Toma de Decisiones , Ejercicio Físico , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Miocardio/patología , Seguridad del Paciente , Medición de Riesgo , Sociedades Médicas , Resultado del Tratamiento , Estados Unidos
5.
J Card Fail ; 18(9): 745-8, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22939044

RESUMEN

BACKGROUND: The unique findings on transthoracic echocardiography of the HeartWare left ventricular assist device (LVAD) have not been previously described. METHODS AND RESULTS: HeartWare LVADs were implanted in 19 patients from May 2009 through December 2010; 152 comprehensive transthoracic echocardiograms (TTEs) performed postoperatively on these patients were retrospectively analyzed for device component visualization, inlet cannula/outflow conduit flow velocities, and imaging artifacts. The inlet cannula was adequately visualized in 66% of studies, incompletely visualized in 14%, and not visualized in 20%. Spectral Doppler interrogation of inlet cannula flow velocity was always uninterpretable due to artifact. Standard parasternal long-axis and apical views always included the inlet cannula in the imaging sector, resulting in a prominent "waterfall" color Doppler artifact obscuring the mitral valve. Inclusion of the inlet cannula in the imaging sector also precluded spectral Doppler interrogation of the mitral valve owing to artifact. The outflow conduit was partially visualized and interrogated by spectral Doppler in 68% of studies, and the average measured peak flow velocity was 1.4 m/s (range 1.0-1.9 m/s). CONCLUSIONS: The HeartWare LVAD inlet cannula and outflow conduit are both readily visualized by TTE in a majority of patients. However, significant color and spectral Doppler artifacts occur when the inlet cannula is visualized in the imaging sector, necessitating routine off-axis Doppler interrogation of the mitral valve.


Asunto(s)
Ecocardiografía , Insuficiencia Cardíaca/terapia , Ventrículos Cardíacos/inervación , Corazón Auxiliar , Insuficiencia Cardíaca/diagnóstico por imagen , Humanos , Válvula Mitral/patología , Estudios Retrospectivos
6.
Catheter Cardiovasc Interv ; 80(3): E50-81, 2012 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-22678595

RESUMEN

The American College of Cardiology Foundation, in collaboration with the Society for Cardiovascular Angiography and Interventions and key specialty and subspecialty societies, conducted a review of common clinical scenarios where diagnostic catheterization is frequently considered. The indications (clinical scenarios) were derived from common applications or anticipated uses, as well as from current clinical practice guidelines and results of studies examining the implementation of noninvasive imaging appropriate use criteria. The 166 indications in this document were developed by a diverse writing group and scored by a separate independent technical panel on a scale of 1 to 9, to designate appropriate use (median 7 to 9), uncertain use (median 4 to 6), and inappropriate use (median 1 to 3). Diagnostic catheterization may include several different procedure components. The indications developed focused primarily on 2 aspects of diagnostic catheterization. Many indications focused on the performance of coronary angiography for the detection of coronary artery disease with other procedure components (e.g., hemodynamic measurements, ventriculography) at the discretion of the operator. The majority of the remaining indications focused on hemodynamic measurements to evaluate valvular heart disease, pulmonary hypertension, cardiomyopathy, and other conditions, with the use of coronary angiography at the discretion of the operator. Seventy-five indications were rated as appropriate, 49 were rated as uncertain, and 42 were rated as inappropriate. The appropriate use criteria for diagnostic catheterization have the potential to impact physician decision making, healthcare delivery, and reimbursement policy. Furthermore, recognition of uncertain clinical scenarios facilitates identification of areas that would benefit from future research. © 2012 Wiley Periodicals, Inc.


Asunto(s)
Cateterismo Cardíaco/normas , Técnicas de Imagen Cardíaca/normas , Cardiología/normas , Enfermedad de la Arteria Coronaria/diagnóstico , Cirugía Torácica/normas , Adulto , Anciano , Enfermedades Cardiovasculares/diagnóstico , Angiografía Coronaria/normas , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Ecocardiografía/normas , Femenino , Adhesión a Directriz , Humanos , Imagen por Resonancia Cinemagnética/normas , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X/normas , Estados Unidos
7.
Int J Cardiol ; 329: 50-55, 2021 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-33359282

RESUMEN

BACKGROUND: Chest radiation therapy (CRT) for malignant thoracic neoplasms is associated with development of valvular heart disease years later. As previous radiation exposure can complicate surgical treatment, transcatheter aortic valve replacement (TAVR) has emerged as an alternative. However, outcomes data are lacking for TAVR patients with a history of CRT. METHODS: We conducted a retrospective study of all patients who underwent a TAVR procedure at a single institution between September 2012 and November 2018. Among 1341 total patients, 50 had previous CRT. These were propensity-matched in a 1:2 ratio to 100 patients without history of CRT. Thirty-day adverse events were analyzed with generalized estimating equation models. Overall mortality was analyzed with stratified Cox regression modelling. RESULTS: Median clinical follow-up was 24 months (interquartile range [IQR], 12-44 months). There was no difference between CRT and non-CRT patients in overall mortality (hazard ratio [HR] 0.84 [0.37-1.90], P = 0.67), 30-day mortality (HR 3.1 [0.49-20.03], P = 0.23), or 30-day readmission rate (HR 1.0 [0.43-2.31], P = 1). There were no differences in the rates of most adverse events, but patients with CRT history had higher rates of postprocedural respiratory failure (HR 3.63 [1.32-10.02], P = 0.01) and permanent pacemaker implantation (HR 2.84 [1.15-7.01], P = 0.02). CONCLUSIONS: For patients with aortic valve stenosis and previous CRT, TAVR is safe and effective, with outcomes similar to those in the general aortic stenosis population. Patients with history of CRT are more likely to have postprocedural respiratory failure and to require permanent pacemaker implantation.


Asunto(s)
Estenosis de la Válvula Aórtica , Implantación de Prótesis de Válvulas Cardíacas , Reemplazo de la Válvula Aórtica Transcatéter , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/cirugía , Humanos , Readmisión del Paciente , Estudios Retrospectivos , Factores de Riesgo , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Resultado del Tratamiento
8.
Circulation ; 117(11): 1478-97, 2008 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-18316491

RESUMEN

The American College of Cardiology Foundation (ACCF) and the American Society of Echocardiography (ASE) together with key specialty and subspecialty societies, conducted an appropriateness review for stress echocardiography. The review assessed the risks and benefits of stress echocardiography for several indications or clinical scenarios and scored them on a scale of 1 to 9 (based upon methodology developed by the ACCF to assess imaging appropriateness). The upper range (7 to 9) implies that the test is generally acceptable and is a reasonable approach, and the lower range (1 to 3) implies that the test is generally not acceptable and is not a reasonable approach. The midrange (4 to 6) indicates a clinical scenario for which the indication for a stress echocardiogram is uncertain. The indications for this review were drawn from common applications or anticipated uses, as well as from current clinical practice guidelines. Use of stress echocardiography for risk assessment in patients with coronary artery disease (CAD) was viewed favorably, while routine repeat testing and general screening in certain clinical scenarios were viewed less favorably. It is anticipated that these results will have a significant impact on physician decision making and performance, reimbursement policy, and will help guide future research.


Asunto(s)
Ecocardiografía de Estrés/normas , Adulto , Anciano , Dolor en el Pecho/diagnóstico , Contraindicaciones , Enfermedad Coronaria/diagnóstico por imagen , Pruebas Diagnósticas de Rutina , Ecocardiografía de Estrés/efectos adversos , Femenino , Humanos , Masculino , Tamizaje Masivo , Persona de Mediana Edad , Revascularización Miocárdica , Cuidados Preoperatorios , Regionalización , Medición de Riesgo
9.
J Card Fail ; 20(2): 65-90, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24556531
11.
Catheter Cardiovasc Interv ; 71(5): E1-19, 2008 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-18314889

RESUMEN

The American College of Cardiology Foundation (ACCF) and the American Society of Echocardiography (ASE) together with key specialty and subspecialty societies, conducted an appropriateness review for stress echocardiography. The review assessed the risks and benefits of stress echocardiography for several indications or clinical scenarios and scored them on a scale of 1 to 9 (based upon methodology developed by the ACCF to assess imaging appropriateness). The upper range (7 to 9) implies that the test is generally acceptable and is a reasonable approach, and the lower range (1 to 3) implies that the test is generally not acceptable and is not a reasonable approach. The midrange (4 to 6) indicates a clinical scenario for which the indication for a stress echocardiogram is uncertain. The indications for this review were drawn from common applications or anticipated uses, as well as from current clinical practice guidelines. Use of stress echocardiography for risk assessment in patients with coronary artery disease (CAD) was viewed favorably, while routine repeat testing and general screening in certain clinical scenarios were viewed less favorably. It is anticipated that these results will have a significant impact on physician decision making and performance, reimbursement policy, and will help guide future research.


Asunto(s)
Enfermedades Cardiovasculares/diagnóstico por imagen , Ecocardiografía de Estrés/normas , Selección de Paciente , Ecocardiografía de Estrés/efectos adversos , Humanos
12.
Tex Heart Inst J ; 35(3): 345-8, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18941647

RESUMEN

Chest-wall trauma can produce bleeding into the pericardium and initiate a process of inflammation, calcification, and scarring that may eventually produce pericardial constriction. Herein, we present an unusual case of a man who experienced chest trauma at age 16 years, and developed heart failure 40 years later secondary to a large, calcified pericardial hematoma. During its prolonged genesis, the pericardial mass became deeply embedded in the myocardium and produced evidence of both constrictive and restrictive cardiomyopathy. Despite attempted surgical resection, the lesion could not be completely removed, nor could its hemodynamic impact be completely resolved.


Asunto(s)
Calcinosis/diagnóstico , Insuficiencia Cardíaca/etiología , Hematoma/diagnóstico , Derrame Pericárdico/diagnóstico , Pericarditis Constrictiva/diagnóstico , Traumatismos Torácicos/complicaciones , Heridas no Penetrantes/complicaciones , Adolescente , Adulto , Calcinosis/cirugía , Diagnóstico Diferencial , Ecocardiografía , Resultado Fatal , Estudios de Seguimiento , Insuficiencia Cardíaca/cirugía , Hematoma/cirugía , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Derrame Pericárdico/cirugía , Pericardiectomía , Pericarditis Constrictiva/cirugía
13.
Tex Heart Inst J ; 35(1): 38-41, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18427650

RESUMEN

Contrast echocardiography is recognized to be a safe, effective technique for evaluating the endocardial border and left ventricular function in patients who have suboptimal non-contrast echocardiograms. However, its use in diagnosing right-heart conditions is less well established. Herein, we report our experience with the use of contrast echocardiography for diagnosing 3 distinct right-sided heart conditions (hypokinesis of the right ventricular free wall, severe tricuspid regurgitation, and cardiac tamponade) in patients who had suboptimal echocardiograms. Further studies should be done to validate the use of contrast echocardiography for diagnosing right-heart conditions.


Asunto(s)
Taponamiento Cardíaco/diagnóstico por imagen , Insuficiencia de la Válvula Tricúspide/diagnóstico por imagen , Disfunción Ventricular Derecha/diagnóstico por imagen , Ecocardiografía Doppler en Color , Femenino , Fluorocarburos , Humanos , Masculino , Microesferas , Persona de Mediana Edad , Embolia Pulmonar/complicaciones , Embolia Pulmonar/diagnóstico , Trombosis de la Vena/diagnóstico por imagen , Disfunción Ventricular Derecha/etiología
14.
Tex Heart Inst J ; 35(1): 76-7, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18427660

RESUMEN

In patients who have cyanosis and dyspnea that are unrelated to a cardiopulmonary cause, 1 rare possible diagnosis is methemoglobinemia. This condition is generally asymptomatic, even when the methemoglobin level is as high as 40% of the total hemoglobin value. In the patient described herein, extensive pulmonologic and cardiologic investigations failed to yield the correct diagnosis, which was finally made on the basis of physical findings and arterial blood-gas analysis. Later, a DNA analysis, reported separately by others, showed that the patient's methemoglobinemia was caused by a novel mutation of the cytochrome b5 reductase gene.


Asunto(s)
Metahemoglobinemia/diagnóstico , Adulto , Cianosis/etiología , Citocromo-B(5) Reductasa/genética , Humanos , Masculino , Metahemoglobinemia/complicaciones , Metahemoglobinemia/genética , Mutación , Oximetría
16.
Tex Heart Inst J ; 33(4): 492-4, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17215978

RESUMEN

Annular submitral left ventricular aneurysm, which predominantly occurs in blacks who live in tropical regions of Africa, is a relatively unknown cardiac condition in the United States. We describe a patient with submitral left ventricular aneurysm who underwent resection of the mass and of the native mitral valve, followed by mitral valve replacement.


Asunto(s)
Aneurisma Cardíaco/cirugía , Implantación de Prótesis de Válvulas Cardíacas , Adulto , Negro o Afroamericano , Aneurisma Cardíaco/diagnóstico por imagen , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/cirugía , Humanos , Masculino , Válvula Mitral/diagnóstico por imagen , Válvula Mitral/cirugía , Radiografía , Estados Unidos
17.
Tex Heart Inst J ; 43(6): 477-481, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28100964

RESUMEN

Chronic tachycardia is a well-known cause of nonischemic cardiomyopathy. We hypothesized that nebivolol, a ß-blocker with nitric oxide activity, would be superior to a pure ß-blocker in preventing tachycardia-induced cardiomyopathy in a porcine model. Fifteen healthy Yucatan pigs were randomly assigned to receive nebivolol, metoprolol, or placebo once a day. All pigs underwent dual-chamber pacemaker implantation. The medication was started the day after the pacemaker implantation. On day 7 after implantation, each pacemaker was set at atrioventricular pace (rate, 170 beats/min), and the pigs were observed for another 7 weeks. Transthoracic echocardiograms, serum catecholamine levels, and blood chemistry data were obtained at baseline and at the end of the study. At the end of week 8, the pigs were euthanized, and complete histopathologic studies were performed. All the pigs developed left ventricular cardiomyopathy but remained hemodynamically stable and survived to the end of the study. The mean left ventricular ejection fraction decreased from baseline by 34%, 20%, and 20% in the nebivolol, metoprolol, and placebo groups, respectively. These changes did not differ significantly among the 3 groups (P =0.51). Histopathologic analysis revealed mild left ventricular perivascular fibrosis with cardiomyocyte hypertrophy in 14 of the 15 pigs. Both nebivolol and metoprolol failed to prevent cardiomyopathy in our animal model of persistent tachycardia and a high catecholamine state.


Asunto(s)
Antagonistas de Receptores Adrenérgicos beta 1/farmacología , Cardiomiopatías/prevención & control , Metoprolol/farmacología , Nebivolol/farmacología , Taquicardia Ventricular/tratamiento farmacológico , Animales , Estimulación Cardíaca Artificial , Cardiomiopatías/etiología , Cardiomiopatías/patología , Cardiomiopatías/fisiopatología , Modelos Animales de Enfermedad , Fibrosis , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/patología , Volumen Sistólico/efectos de los fármacos , Sus scrofa , Taquicardia Ventricular/etiología , Taquicardia Ventricular/fisiopatología , Función Ventricular Izquierda/efectos de los fármacos , Remodelación Ventricular/efectos de los fármacos
18.
J Am Coll Cardiol ; 43(1): 77-84, 2004 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-14715187

RESUMEN

OBJECTIVES: The goal of this study was to evaluate whether quantitation of thrombus burden with transesophageal echocardiography (TEE) can help risk-stratify patients undergoing thrombolysis of prosthetic valve thrombosis (PVT). BACKGROUND: Thrombolytic therapy of PVT has an unpredictable risk of embolization and complications. METHODS: An international registry of patients with suspected PVT undergoing two-dimensional/Doppler and TEE before thrombolysis was established. All TEE studies were reviewed and quantitated by a single observer blinded to all data. RESULTS: From 1985 to 2001, 107 patients (71 females; age 24 to 86 years) from 14 centers (6 in the U.S.) were identified. The majority of cases involved the mitral valve (79 mitral, 13 aortic, and 15 tricuspid). Hemodynamic success rate was achieved in 85% and was similar across valves. Overall complications were observed in 17.8%, and death in 5.6%. Predictors of complications were: New York Heart Association (NYHA) functional class, presence of shock, sinus tachycardia, hypotension, previous history of stroke, thrombus extension beyond the valve ring, and thrombus area. Multivariate analysis demonstrated that two variables were independent predictors of complications: thrombus area by TEE (odds ratio [OR] 2.41 per 1 cm2 increment, 95% confidence interval [CI] 1.12 to 5.19) and prior history of stroke (OR 4.55, 95% CI 1.35 to 15.38). A thrombus area <0.8 cm2 identified patients at lower risk for complications from thrombolysis, irrespective of NYHA functional class. CONCLUSIONS: In PVT, the thrombus size imaged with TEE is a significant independent predictor of outcome. Transesophageal echocardiography can identify low-risk groups for thrombolysis irrespective of symptom severity and is therefore recommended in the management of prosthetic valve thrombosis.


Asunto(s)
Ecocardiografía Transesofágica , Prótesis Valvulares Cardíacas/efectos adversos , Terapia Trombolítica , Trombosis/diagnóstico por imagen , Trombosis/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Sistema de Registros , Medición de Riesgo , Terapia Trombolítica/efectos adversos , Trombosis/etiología
19.
Tex Heart Inst J ; 32(3): 263-70, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16392203

RESUMEN

From April 2000 through September 2001, we studied 11 patients with the Jarvik 2000--a left ventricular assist device with an axial-flow pump that provides continuous blood flow--to determine the echocardiographic characteristics. All patients underwent complete echocardiographic examination, including outflow-graft flow evaluation 24 hours after implantation and each month thereafter for the duration of support. Data were obtained at each pump setting (8000-12000 rpm in 1000-rpm increments) and with the pump off. Left ventricular dimensions and shortening fraction and the duration of aortic valve systolic opening decreased as pump speed increased. Although the aortic valve remained closed at higher pump speeds, pump outflow-graft flow remained pulsatile, because of the systolic thrust of the assisted ventricle. Systolic dominance of phasic flow was more pronounced at lower pump speeds, due to normalization of the diseased heart's Starling response. When the aortic valve was closed continuously, echocardiographic contrast (indicating blood stasis) was noted in the aortic root. Because of the pump outflow graft's proximity to the chest wall, device output could be measured independently of cardiac contributions. Mean peak outflow-graft flow velocities were 0.75 +/- 0.30 m/s (systolic) and 0.41 +/- 0. 13 m/s (diastolic). When the pump was turned off briefly there was minimal regurgitation through the device into the left ventricle. This 1st echocardiographic heart function analysis of the Jarvik 2000 confirms that the device unloads the ventricle and increases cardiac output. Cardiac responses to device-speed changes can be evaluated readily with echocardiography in the early and late postoperative period.


Asunto(s)
Ecocardiografía/métodos , Insuficiencia Cardíaca/terapia , Corazón Auxiliar , Velocidad del Flujo Sanguíneo , Femenino , Estudios de Seguimiento , Insuficiencia Cardíaca/diagnóstico por imagen , Insuficiencia Cardíaca/fisiopatología , Trasplante de Corazón , Humanos , Masculino , Persona de Mediana Edad , Diseño de Prótesis , Implantación de Prótesis , Estudios Retrospectivos
20.
Ann Thorac Surg ; 77(1): 196-202, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14726061

RESUMEN

BACKGROUND: The bileaflet valve is currently the mechanical replacement valve of choice. Though durable, it does not closely mimic native valve hemodynamics and remains potentially thrombogenic. METHODS: Prototype trileaflet valves (T1 and T2) were implanted in the mitral position in calves. Group I calves received either a T1 valve (n = 12) or a control bileaflet valve (n = 5); Group II, either a T2 valve (n = 7) or a control bileaflet valve (n = 5). Valve function, perivalvular leakage, and transvalvular pressure gradients were evaluated. Also, long-term prototype leaflet wear was evaluated in vivo in one Group I calf (502 days) and two Group II calves (385 and 366 days). Calves were euthanized and necropsied at study termination, and major organs weighed and examined. RESULTS: Valve function was excellent and hematologic parameters remained normal in all calves that survived to study termination. Mean peak transvalvular pressure gradients were 10 +/- 7 mm Hg for T1 valves, 6 +/- 3 mm Hg for T2 valves, and 12 +/- 4 mm Hg for bileaflet control valves. Clinically insignificant valvular regurgitation was observed in both prototypes. Explanted valves showed no thrombus-impaired leaflet motion, except in two T1-fitted calves and one T2-fitted calf. Major organs showed no evidence of clinically significant thromboembolic events. There were no other significant differences between the results of experimental and control groups. CONCLUSIONS: Prototype trileaflet valves performed safely and effectively in the mitral position in calves, even without long-term anticoagulation. This warrants their evaluation as an equivalent alternative to bileaflet valves.


Asunto(s)
Prótesis Valvulares Cardíacas , Válvula Mitral , Animales , Bovinos , Prótesis Valvulares Cardíacas/efectos adversos , Pruebas Hematológicas , Válvula Mitral/diagnóstico por imagen , Válvula Mitral/patología , Válvula Mitral/cirugía , Complicaciones Posoperatorias/epidemiología , Diseño de Prótesis , Ultrasonografía
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