RESUMEN
BACKGROUND: Off-pump coronary artery bypass grafting (OPCABG) has assumed an increasing role in many surgical practices. The ideal candidate has not been defined, but high-risk patients seem to benefit most when cardiopulmonary bypass (CPB), aortic cross clamping and cardioplegic arrest are avoided. METHODS: Fourteen high-risk patients (age 52 to 81 years, 1 female, EF 44%+/-8, Parsonnet score 23+/-4) were studied. They presented with acute coronary syndroms on platelet glycoprotein IIb/IIIa antagonists, acute myocardial infarction, worsening renal failure, decompensating ischemic cardiomyopathy, religious beliefs and denial of blood transfusion, and severe peripheral/cerebrovascular disease (total bilateral internal carotid artery occlusion and/or >90% stenosis). These patients underwent OPCABG via sternotomy with the intention of complete coronary revascularization. RESULTS: An average of 2.3 grafts/patient were performed and the posterior descending artery (PDA) and marginal branches of the circumflex artery (LCX) were grafted in 79% of the patients. There were 3 events of intraoperative cardiac arrest precipitated by occlusion of right coronary artery (RCA) or positioning a cardiomegaly heart leading to immediate intravascular shunting (2) and/or conversion to CPB (1). One patient was converted to CPB and graft revision (intraoperative ultrasound and probing). The mortality rate was 0% and one stroke was observed on post-operative day 1. Coronary angiography (n=6) showed no significant stenosis. CONCLUSIONS: OPCABG complete revascularization is feasible in high-risk patients with low morbidity and mortality and excellent early RESULTS: OPCABG may be indicated in patients on platelet receptor antagonists preventing bleeding complications. Cardiomegaly can cause difficult off-pump LCX and PDA exposure and stabilization. RCA grafting off-pump is less tolerated and PDA grafting is preferred. High-risk patients for CPB are the ones who may benefit the most from OPCABG.
Asunto(s)
Revascularización Miocárdica/métodos , Anciano , Anciano de 80 o más Años , Puente de Arteria Coronaria/efectos adversos , Puente de Arteria Coronaria/métodos , Enfermedad Coronaria/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Riesgo , Resultado del TratamientoRESUMEN
BACKGROUND: Percutaneous coronary intervention (PCI) and coronary artery bypass graft surgery (CABG) are being applied to high-risk populations, but previous randomized trials comparing revascularization methods have excluded a number of important high-risk groups. OBJECTIVES: This five-year, multicenter, randomized clinical trial was designed to compare long-term survival among patients with medically refractory myocardial ischemia and a high risk of adverse outcomes assigned to either a CABG or a PCI strategy, which could include stents. METHODS: Patients from 16 Veterans Affairs Medical Centers were screened to identify myocardial ischemia refractory to medical management and the presence of one or more risk factors for adverse outcome with CABG, including prior open-heart surgery, age >70 years, left ventricular ejection fraction <0.35, myocardial infarction within seven days or intraaortic balloon pump required. Clinically eligible patients (n = 2,431) underwent coronary angiography; 781 were angiographically acceptable; 454 (58% of eligible) patients consented to random assignment between CABG and PCI. RESULTS: A total of 232 patients was randomized to CABG and 222 to PCI. The 30-day survivals for CABG and PCI were 95% and 97%, respectively. Survival rates for CABG and PCI were 90% versus 94% at six months and 79% versus 80% at 36 months (log-rank test, p = 0.46). CONCLUSIONS: Percutaneous coronary intervention is an alternative to CABG for patients with medically refractory myocardial ischemia and a high risk of adverse outcomes with CABG.
Asunto(s)
Angioplastia Coronaria con Balón , Puente de Arteria Coronaria , Isquemia Miocárdica/mortalidad , Isquemia Miocárdica/terapia , Anciano , Angina de Pecho/mortalidad , Angina de Pecho/cirugía , Angina de Pecho/terapia , Humanos , Isquemia Miocárdica/cirugía , Factores de Riesgo , StentsRESUMEN
This multicenter, prospective randomized trial was designed to test the hypotheses that percutaneous coronary intervention (PCI) is a safe and effective alternative to coronary artery bypass grafting (CABG) for patients with refractory ischemia and high risk of adverse outcomes. As a comparison of revascularization strategies, the trial specifically allows surgeons and interventionists to use new techniques as they become clinically available. After 42 months of this 72-month trial, 17,624 patients have been screened and 2022 met eligibility requirements: 341 have been randomized to either CABG or PCI, and the remaining 1681 are being prospectively followed in a registry. The 3-year overall survival of patients in the registry and randomized trial is comparable. To enhance accrual into the randomized trial, site visits were conducted, a few low-accruing hospitals were put on probation and/or replaced, eligibility criteria were reviewed at annual meetings of investigators, and the accrual period was extended by 1 year. These data demonstrate that a prospective randomized trial and registry of coronary revascularization for medically refractory high-risk patients is feasible.
Asunto(s)
Puente de Arteria Coronaria , Isquemia Miocárdica/terapia , Revascularización Miocárdica , Factores de Edad , Anciano , Angina Inestable/complicaciones , Gasto Cardíaco Bajo/complicaciones , Estudios de Factibilidad , Estudios de Seguimiento , Humanos , Contrapulsador Intraaórtico , Isquemia Miocárdica/cirugía , Selección de Paciente , Estudios Prospectivos , Recurrencia , Sistema de Registros , Reoperación , Factores de Riesgo , Tasa de Supervivencia , Resultado del TratamientoRESUMEN
BACKGROUND: Patients presenting for coronary artery bypass graft (CABG) surgery may have concurrent asymptomatic aortic stenosis (AS) or aortic insufficiency (AI). This retrospective study was performed to evaluate outcomes in patients with aortic valve disease undergoing CABG with or without aortic valve replacement (AVR). METHODS: Study groups included 414 patients undergoing combined AVR and CABG (AVR-CABG group) and 62 patients with asymptomatic mild-to-moderate AS, AI, or both undergoing CABG but not AVR (CABG group). End points included 30-day mortality rate, time to cardiac mortality, time to all-cause mortality, and time to aortic valve reoperation. Reoperation refers to surgery for replacement of the native aortic valve in the CABG group or replacement of the prosthetic aortic valve in the AVR-CABG group. Important patient characteristics affecting outcomes were determined by using Cox proportional-hazard analysis. These variables were then included in multivariable analyses by using logistic regression analysis and Cox proportional-hazard modeling to compare outcomes between each patient group. RESULTS: No difference was seen in any of the mortality end points between the CABG group and the AVR-CABG group after controlling for significant differences between the groups. However, the need for reoperation for AVR was significantly higher for the CABG group than the AVR-CABG group. For patients followed for up to 6 years, the estimated need for aortic valve reoperation was 24.3% in the CABG group versus 3% in the AVR-CABG group. CONCLUSION: On the basis of these results, patients with asymptomatic AS or AI should be considered for AVR at the time of CABG.
Asunto(s)
Insuficiencia de la Válvula Aórtica/epidemiología , Estenosis de la Válvula Aórtica/epidemiología , Puente de Arteria Coronaria , Enfermedad Coronaria/cirugía , Anciano , Válvula Aórtica , Insuficiencia de la Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/cirugía , Estudios de Casos y Controles , Puente de Arteria Coronaria/mortalidad , Enfermedad Coronaria/mortalidad , Implantación de Prótesis de Válvulas Cardíacas , Humanos , Modelos Logísticos , Modelos de Riesgos Proporcionales , Reoperación , Tasa de SupervivenciaRESUMEN
PIP: The associations between gender role orientation and high-risk sex behaviors were explored in a study of 400 sexually active women 16-24 years of age (mean, 20.4 years) recruited from two metropolitan family planning clinics in Queensland, Australia. Three dimensions of gender role orientation were examined: gender role personality traits, gender role attitudes, and gender role dating behavior. It was hypothesized that women with more nontraditional or "masculine" characteristics are more likely than those with traditional or "feminine" characteristics to engage in unsafe sexual behaviors. Only partial support was found for this hypothesis. Although a number of univariate relationships emerged, very few associations between sexual behavior and gender roles remained significant in the multivariate analysis. Logistic regression analysis indicated that women with two or more sexual partners in the year preceding the study were significantly more likely than those with 0-1 sex partners to have masculine personality traits and to be more liberal in their attitudes toward women in society. Nonuse of condoms with the most recent sexual partner was not significantly associated with the gender role variables; however, women who reported masculine dating behaviors were more likely to have used a condom with their most recent nonsteady sexual partner. Similarly, substance use before or during last sexual intercourse was associated with masculine traits when the partner was nonsteady but was not related to gender role orientation when the partner was steady. The association of "masculine" personality traits with multiple partners and substance use indicates that caution should be exercised in assuming that masculine gender role characteristics are beneficial for women in sexual situations.^ieng
Asunto(s)
Consumo de Bebidas Alcohólicas , Condones , Relaciones Interpersonales , Personalidad , Asunción de Riesgos , Conducta Sexual , Parejas Sexuales , Estadística como Asunto , Mujeres , Australia , Conducta , Anticoncepción , Países Desarrollados , Servicios de Planificación Familiar , Islas del Pacífico , Psicología , Investigación , Conducta SocialRESUMEN
BACKGROUND: Alterations in cardiac efficiency may signal pathologic stresses and energetic adaptation during aortic regurgitation (AR). METHODS AND RESULTS: LV systolic function, left coronary blood flow, and AVO2 difference were measured in conscious dogs to assess LV and contractile efficiencies at baseline, 1 day (n=10), 1 week (n=10), and 3 weeks (n=8) of AR. LV systolic function was assessed by the preload recruitable stroke work relationship. Total LV Efficiency (TEFF=SWxHeart Rate/MVO2) and contractile efficiency (CEFF=1/the slope of the MVO2 -pressure-volume area relationship) and steady-state potential energy (PVA-SWxHR), mechanical coupling efficiency (MCE=SWxHR/PVA) were calculated. LV systolic function decreased by 17% at 1 day (P<.05) and by 24% at 3 weeks (P<.05). CEFF decreased from 58+/-8% to 38+/-10% (P<.05) at 1 day, normalized at 1 week, and decreased to 28+/-14% at 3 weeks (P<.05). TEFF was not altered at 1 day and 1 week but decreased by 3 weeks (P<.05). MCE trended downward from baseline of 47+/-5%, reaching significance at 3 weeks (34+/-6%, P<.05). CONCLUSIONS: CEFF decreases acutely, indicating diminished economy of myocardial contraction. CEFF normalizes at 1 week, suggesting adequate compensation. TEFF is not altered in early AR. By 3 weeks, LV systolic dysfunction is accompanied by depressed TEFF, mechanical coupling, and CEFF signaling the onset of decompensated AR. Thus, volume overload of acute AR resulted in early compensation at the expense of myocardial efficiency with subsequent global dysfunction characterized by depressed LV systolic mechanics, mechanical, coupling, and contractile efficiencies.
Asunto(s)
Insuficiencia de la Válvula Aórtica/fisiopatología , Metabolismo Energético , Miocardio/metabolismo , Enfermedad Aguda , Animales , Perros , Contracción Miocárdica , Consumo de Oxígeno , Función Ventricular IzquierdaRESUMEN
BACKGROUND: Whether biological or mechanical valves should be used in patients on chronic dialysis therapy remains to be clearly defined. METHODS: A retrospective review was performed on 19 consecutive patients from our institution with end-stage renal disease on chronic peritoneal or hemodialysis undergoing aortic (n = 12), mitral (n = 5), or aortic-mitral (n = 2) valve replacement. RESULTS: The 9 biological and 10 mechanical valve patients had similar ages (56.5 versus 56.6 years) and cardiovascular risk factors. The overall estimated Kaplan-Meier survival was 60% +/- 12% at 12 months and 42% +/- 14% at 60 months. Mechanical valve patients had a significantly higher rate of postoperative cerebrovascular accidents or bleeding complications (10/10 versus 0/9; chi 2 = 17.0; p < 0.001). No subsequent reoperations were required for biological valve failure at a mean follow-up of 32 +/- 53 months. CONCLUSIONS: These results demonstrate that in patients with end-stage renal disease, use of mechanical valves is associated with significant risk of complications, whereas biological valve failure from prosthetic dysfunction is unusual. Overall survival is poor in both groups of patients. Therefore, preference should be given to biological valve instead of mechanical valve prostheses in patients on chronic renal dialysis.
Asunto(s)
Bioprótesis , Prótesis Valvulares Cardíacas , Fallo Renal Crónico/terapia , Diálisis Renal , Anciano , Endocarditis Bacteriana/cirugía , Enfermedades de las Válvulas Cardíacas/complicaciones , Humanos , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/mortalidad , Persona de Mediana Edad , Diálisis Peritoneal , Estudios Retrospectivos , Tasa de SupervivenciaRESUMEN
A new practical descriptor of metabolic to mechanical myocardial energy transfer (MET), termed the virtual work model, was evaluated in 32 conscious dogs and in 8 isolated canine hearts. An index of total mechanical energy expenditure (TME) was calculated as the sum of external energy (stroke work) and an internal energy index of heat (left ventricular end-diastolic volume times left ventricular mean ejection pressure). Physiological comparison of TME (x-axis) and myocardial oxygen consumption (MVO2; y-axis) yielded highly linear MET relationships (mean r = 0.93 +/- 0.07), with an average slope of 0.86 +/- 0.39 (SD) and a y-intercept of 9.1 +/- 6.4 mW/ml myocardium. The linear MVO2-TME relationship did not vary under steady-state vs. dynamic vena caval occlusion, increased heart rate, increased afterload, or increased inotropic state with calcium infusion. Compared with five other indexes of myocardial energetics, the virtual work model of MET was the most linear, the most practical in not requiring determination of the end-systolic pressure-volume relationship, and the most accurate predictor of MVO2 under normal and altered hemodynamic conditions.
Asunto(s)
Miocardio/metabolismo , Consumo de Oxígeno , Animales , Fenómenos Biomecánicos , Constricción Patológica , Perros , Metabolismo Energético , Frecuencia Cardíaca , Hemodinámica , Homeostasis , Técnicas In Vitro , Modelos Cardiovasculares , Contracción Miocárdica , Venas Cavas/fisiopatologíaRESUMEN
The major HIV/AIDS-related issues facing women in Australia are outlined. From a global epidemiological perspective, women in Australia have almost gone unscathed by HIV infection. However, the potential for widespread infection cannot be ignored. The greatest threat for the majority of women in Australia is infection through sexual transmission. Although HIV infection is preventable, there are many social and economic factors that may hinder women's efforts to protect themselves. A major result of the global AIDS epidemic for women in Australia has been caring for a family member who has been infected with HIV. When a member of the family, usually a son, develops AIDS and is cared for at home, it is usually his mother who cares for him. She may face many difficult issues that may affect her health and well-being. Thus the small number of women infected with HIV in Australia does not accurately represent the impact the disease has had, and may potentially have, on the women of Australia.
Asunto(s)
Infecciones por VIH , Salud de la Mujer , Australia/epidemiología , Cuidadores , Costo de Enfermedad , Femenino , Infecciones por VIH/epidemiología , Infecciones por VIH/enfermería , Infecciones por VIH/prevención & control , Humanos , Factores de RiesgoRESUMEN
The physiological effects of intravenous ouabain on left ventricular (LV) systolic function and metabolic-to-mechanical energy transfer were examined in eight conscious dogs. LV pressure and volume were measured using micromanometers and ultrasonic dimension transducers during transient vena caval occlusions under control conditions and after increasing doses of ouabain. Doppler coronary flow and coronary sinus O2 saturations were used to determine arterial-to-coronary sinus O2 content difference and thereby to calculate LV O2 consumption; total mechanical energy was computed as the sum of LV stroke work and the product of end-diastolic volume and LV mean ejection pressure, neglecting LV unstressed cavitary volume. The slope (10(4) erg/ml) of the stroke work vs. end-diastolic volume relationship increased progressively with rising doses of ouabain from 7.0 +/- 1.6 at control to 9.6 +/- 1.7 after ouabain 0.75 mg (P = 0.0002). Regression analysis of LV O2 consumption (mW/cm3) vs. total mechanical energy (mW/cm3) yielded a linear relationship that did not change with 0.75 mg of ouabain (P > 0.4). These data indicate that ouabain possesses a significant positive inotropic effect on the intact left ventricle without a change in energy transfer efficiency or O2 wasting.
Asunto(s)
Corazón/fisiología , Miocardio/metabolismo , Ouabaína/farmacología , Consumo de Oxígeno/efectos de los fármacos , Animales , Estado de Conciencia , Diástole/efectos de los fármacos , Perros , Relación Dosis-Respuesta a Droga , Metabolismo Energético/efectos de los fármacos , Corazón/efectos de los fármacos , Oxígeno/sangre , Análisis de Regresión , Volumen Sistólico/efectos de los fármacos , Función Ventricular Izquierda/efectos de los fármacos , Función Ventricular Izquierda/fisiologíaRESUMEN
A prospective community study looked at drinking behavior and biopsychosocial correlates of adolescents (in years 9 and 10 and again in years 11 and 12 at 23 high schools) and their parents. Heavy drinkers were compared to nil/low drinkers. Sons were more likely to drink heavily if fathers drank heavily and mothers who drank heavily were more likely to cohabit with heavy drinkers. Differences in psychological characteristics and home environment were defined in regard to heavy drinking fathers and drinking sons. Difficulty in settling disagreements and reduced time spent with family were the main correlates associated with drinking by both boys who did not necessarily have a heavy drinking father and those who did.
Asunto(s)
Alcoholismo/psicología , Hijo de Padres Discapacitados/psicología , Conducta Paterna , Desarrollo de la Personalidad , Adolescente , Adulto , Consumo de Bebidas Alcohólicas/psicología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Conducta Materna , Persona de Mediana Edad , Responsabilidad Parental/psicología , Factores de Riesgo , Medio SocialRESUMEN
The need for a better organ preservative solution in heart transplantation is clear. At the same time, newer techniques in the assessment of cardiac function in the laboratory have made accurate load-independent quantification of myocardial preservation possible. Therefore a study was undertaken to evaluate left ventricular function in transplanted hearts after 14 hours of preservation in the intracellular lactobionate solution. Nine dogs were instrumented with ultrasonic dimension transducers, to measure left ventricular epicardial volume, and with micromanometers, to measure left ventricular pressure. Left ventricular wall volumes were determined from epicardial echocardiograms. To define the extent of organ injury resulting from the transplant procedure and cardiopulmonary bypass alone, four other animals were instrumented in a similar fashion, and left ventricular function was assessed after standard cardioplegic arrest and transplantation. The transplant procedures were performed with a warm ischemic period of 0.75 +/- 0.2 hours. In all experiments, data were collected before graft harvest and 1 hour after separation from cardiopulmonary bypass. Standard cardioplegic arrest and 2.4 +/- 0.1 hours of ischemia resulted in a decrease in left ventricular ejection fraction from 0.43 +/- 0.04 to 0.27 +/- 0.1 (37%) (p less than 0.01), a decrease in the slope of the stroke work/end-diastolic volume relationship from 15.4 +/- 7.9 to 7.9 +/- 2.0 erg X 10(4) (49%; p less than 0.01), and a decrease in the myocardial power output from 19.7 +/- 10.9 to 5.9 +/- 1.9 (70%; p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)