RESUMEN
OBJECTIVE: To examine the safety and applicability of off pump coronary artery bypass surgery (OPCAB) in patients with significant left ventricular dysfunction and to discuss the clinical implications for the surgical methods. DESIGN: Retrospective study. SETTING: Tertiary care university affiliated referral centre. PARTICIPANTS: 353 consecutive patients with preoperative left ventricular ejection fraction < or = 35% who underwent coronary artery bypass over a three year period. MAIN OUTCOME MEASURES: Postoperative morbidity and mortality. METHODS: 144 patients operated by OPCAB were compared with 209 patients operated by conventional coronary artery bypass. Multivariate and univariate analyses were performed on the pre- and postoperative variables to predict risk factors associated with hospital morbidity and mortality. RESULTS: Patients in the OPCAB group were more likely to be women and to have congestive heart failure, chronic obstructive pulmonary disease, hypertension, and diabetes; patients in the on pump group were more likely to have had a recent myocardial infarction and to have more severe angina pectoris and an urgent/emergent status. The groups did not differ significantly in length of stay, major postoperative complication rates, or mortality. Comparison of the impact of the procedures on surgical methods over time showed an increase in the use of OPCAB (13% to 67%), without any impact on morbidity or mortality. CONCLUSIONS: OPCAB is feasible and applicable for patients with depressed left ventricular function. This high risk group can potentially benefit from the off pump approach.
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Puente de Arteria Coronaria Off-Pump , Disfunción Ventricular Izquierda/cirugía , Anciano , Puente de Arteria Coronaria Off-Pump/efectos adversos , Puente de Arteria Coronaria Off-Pump/métodos , Puente de Arteria Coronaria Off-Pump/tendencias , Estudios de Factibilidad , Femenino , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Factores de Riesgo , Resultado del TratamientoRESUMEN
OBJECTIVE: Retrospective comparisons of selected patients undergoing off-pump versus conventional on-pump coronary artery bypass grafting have yielded inconsistent results and raised concerns about completeness of revascularization in off-pump coronary artery bypass grafting. METHODS: Two hundred unselected patients referred for elective primary coronary artery bypass grafting were randomly assigned to undergo off-pump coronary artery bypass grafting with an Octopus tissue stabilizer (Medtronic, Inc, Minneapolis, Minn) or conventional coronary artery bypass grafting with cardiopulmonary bypass by a single surgeon. Revascularization intent determined before random assignment was compared with the revascularization performed. All management followed strict, unbiased, criteria-driven protocols. Patients and nonoperative care providers were blinded to surgical group. RESULTS: Baseline characteristics were similar. The number of grafts performed per patient (mean +/- SD 3.39 +/- 1.04 for off-pump coronary artery bypass grafting, 3.40 +/- 1.08 for conventional coronary artery bypass grafting) and the index of completeness of revascularization (number of grafts performed/number of grafts intended, 1.00 +/- 0.18 for off-pump coronary artery bypass grafting, 1.01 +/- 0.09 for conventional coronary artery bypass grafting) were similar. Likewise, the index of completeness of revascularization was similar between groups for the lateral wall. Combined hospital and 30-day mortalities and stroke rates were similar. Postoperative myocardial serum enzyme measures were significantly lower after off-pump coronary artery bypass grafting, suggesting less myocardial injury. Adjusted postoperative thromboelastogram indices, fibrinogen, international normalized ratio, and platelet levels all showed significantly less coagulopathy after off-pump coronary artery bypass grafting. Patients undergoing off-pump coronary artery bypass grafting received fewer units of blood, were more likely to avoid transfusion altogether, and had a higher hematocrit at discharge. Cardiopulmonary bypass was an independent predictor of transfusion (odds ratio 2.42, P =.0073) by multivariate analysis. More patients undergoing off-pump coronary artery bypass grafting were extubated in the operating room and within 4 hours. Postoperative length of stay (in days) was shorter for off-pump coronary artery bypass grafting (5.1 +/- 6.5 for off-pump coronary artery bypass grafting, 6.1 +/- 8.2 for conventional coronary artery bypass grafting, P =.005 by Wilcoxon test). One patient (in the conventional coronary artery bypass grafting group) required angioplasty for graft closure within 30 days. CONCLUSIONS: When compared with conventional coronary artery bypass grafting with cardiopulmonary bypass, off-pump coronary artery bypass grafting achieved similar completeness of revascularization, similar in-hospital and 30-day outcomes, shorter length of stay, reduced transfusion requirement, and less myocardial injury.
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Puente de Arteria Coronaria/métodos , Transfusión Sanguínea , Femenino , Estudios de Seguimiento , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estudios RetrospectivosRESUMEN
BACKGROUND: Aortic cross-clamping is contraindicated in patients with severe atherosclerosis of the ascending aorta, and administration of chemical cardioplegia may be cumbersome in these patients. In this study, we demonstrate an alternative method of achieving cardioplegia by electrical stimulation of the vagus nerve. METHODS: In anesthetized canines, the left anterior descending coronary artery was reversibly ligated for 90 minutes, followed by cardiopulmonary bypass (CPB) and randomization to three groups (n = 8 each): (1) BCP group: 1 hour of intermittent hypothermic (4 degrees C) blood cardioplegia infusion; (2) CPB group: 1 hour of CPB alone; (3) EP group (group receiving electroplegia): 1 hour of intermittent vagal stimulation (total of 60 20-second electrical stimuli at 40 Hz, 6 to 10 V) with adjunctive pyridostigmine (0.5 mg/kg), verapamil (50 microg/kg), and propranolol (80 microg/kg) to potentiate hyperpolarization and suppress ectopic escape beats. RESULTS: The EP group achieved consistent intervals of arrest with 3.8 +/- 1.2 escape beats per 20-second stimulation period. After 2 hours of reperfusion off CPB, the left anterior descending coronary artery segmental shortening was reduced from baseline in all groups, but the segmental shortening recovered to a greater extent in the EP group than in either the CPB or BCP group (2.4% +/- 1.4% versus -1.3% +/- 1.3% versus -4.0% +/- 0.8%, p < 0.05). Infarct size (TTC stain, percentage of area at risk) was comparable among groups (EP: 20.9% +/- 4.7%; CPB: 29.6% +/- 3.2%; BCP: 25.1% +/- 5.7%). Postischemic left anterior descending coronary artery endothelial function (percent maximum relaxation to acetylcholine) was depressed in the EP group (68.6% +/- 7.6% versus 102.3% +/- 6.4%, p < 0.05), but was comparable versus nonischemic circumflex function in the BCP group (77.1% +/- 11.9% versus 100.4% +/- 10.0%, p = 0.15) and the CPB group (93.8% +/- 6.6% versus 93.3% +/- 6.6%). CONCLUSIONS: Electroplegia achieves elective intermittent cardiac arrest, avoids hypothermia, chemical cardioplegia, and aortic cross-clamping, with physiological outcomes comparable to blood cardioplegia.
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Procedimientos Quirúrgicos Cardíacos , Puente Cardiopulmonar , Estimulación Eléctrica , Paro Cardíaco Inducido/métodos , Nervio Vago/fisiología , Acetilcolina/farmacología , Animales , Antiarrítmicos/administración & dosificación , Sangre , Presión Sanguínea , Agua Corporal/metabolismo , Vasos Coronarios/efectos de los fármacos , Vasos Coronarios/fisiopatología , Creatina Quinasa/sangre , Perros , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/fisiopatología , Frecuencia Cardíaca , Contracción Miocárdica , Infarto del Miocardio/patología , Infarto del Miocardio/fisiopatología , Reperfusión Miocárdica , Miocardio/metabolismo , Peroxidasa/metabolismo , Propranolol/administración & dosificación , Bromuro de Piridostigmina/administración & dosificación , Vasodilatadores/farmacología , Verapamilo/administración & dosificaciónRESUMEN
BACKGROUND: Hemodynamic stability during cardiac manipulation for complex, multivessel off-pump coronary artery bypass grafting (OPCAB) remains problematic. METHODS: A servo-controlled pump has been utilized to deliver warm whole blood to coronary grafts prior to construction of proximal anastomoses. RESULTS: This technique may avoid detrimental hemodynamic decompensation, which may accompany regional coronary ischemia during cardiac displacement. It may also allow precise infusion of supplemental additives leading to coronary vasodilatation, myocardial resuscitation, and enhancement of myocardial contractility. CONCLUSION: In this report, three complex OPCAB cases are described which were successfully performed with active graft perfusion and which might not otherwise have been technically feasible by conventional OPCAB techniques.
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Puente de Arteria Coronaria/métodos , Anciano , Puente de Arteria Coronaria/instrumentación , Circulación Coronaria , Corazón Auxiliar , Humanos , Bombas de Infusión , Masculino , Persona de Mediana Edad , ReoperaciónRESUMEN
BACKGROUND: This retrospective study compared clinical outcomes and resource utilization in patients having off-pump coronary artery bypass grafting (OPCAB) versus conventional coronary artery bypass grafting (CABG). Angiographic patency was documented in the OPCAB group. METHODS: From April 1997 through November 1999, OPCAB was performed in 200 consecutive patients, and the results were compared with those in a contemporaneous matched control group of 1,000 patients undergoing CABG. Patients were matched according to age, sex, preexisting disease (renal failure, diabetes, pulmonary disease, stroke, hypertension, peripheral vascular disease, previous myocardial infarction, and primary or redo status. Follow-up in the OPCAB patients was 93% and averaged 13.4 months. RESULTS: Hospital death (1.0%), postoperative stroke (1.5%), myocardial infarction (1.0%), and re-entry for bleeding (1.5%) occurred infrequently in the OPCAB group. There were reductions in the rates of transfusion (33.0% versus 70.0%; p < 0.001) and deep sternal wound infection (0% versus 2.2%; p = 0.067) in the OPCAB group compared with the CABG group. Angiographic assessment of 421 grafted arteries was performed in 167 OPCAB patients (83.5%) prior to hospital discharge. All but five were patent (98.8%) (93.3% FitzGibbon A, 5.5% FitzGibbon B, 1.2% FitzGibbon O). All 163 internal mammary artery grafts were patent. Off-pump coronary artery bypass grafting reduced postoperative hospital stay from 5.7 +/- 5.3 days in the CABG group to 3.9 +/- 2.6 days (p < 0.001), with a decrease in hospital cost of 15.0% (p < 0.001). CONCLUSIONS: Off-pump coronary artery bypass grafting reduces hospital cost, postoperative length of stay, and morbidity compared with CABG on cardiopulmonary bypass. Off-pump coronary bypass grafting is safe, cost effective, and associated with excellent graft patency and clinical outcomes.
Asunto(s)
Puente Cardiopulmonar/economía , Angiografía Coronaria/economía , Puente de Arteria Coronaria/economía , Enfermedad Coronaria/cirugía , Costos de Hospital/estadística & datos numéricos , Complicaciones Posoperatorias/economía , Anciano , Anciano de 80 o más Años , Enfermedad Coronaria/diagnóstico por imagen , Enfermedad Coronaria/economía , Enfermedad Coronaria/mortalidad , Ahorro de Costo , Femenino , Estudios de Seguimiento , Mortalidad Hospitalaria , Humanos , Tiempo de Internación/economía , Masculino , Persona de Mediana Edad , Readmisión del Paciente/economía , Complicaciones Posoperatorias/diagnóstico por imagen , Complicaciones Posoperatorias/mortalidad , Tasa de SupervivenciaRESUMEN
Myocardial protection during off-pump coronary artery bypass surgery (OPCAB) is a multifactorial problem. Careful, individualized choice of graft sequence and maintenance of stable systemic hemodynamics are of central importance. Recently refined techniques for atraumatic rotation of the heart and visualization of coronary anastomoses allow precise and controlled grafting of all coronary territories without cardiopulmonary bypass in the large majority of cases. Perfusion-assisted direct coronary artery bypass (PADCAB) techniques, in which coronary perfusion pressure is independent of systemic arterial pressure, can avoid or abort a downward hemodynamic spiral, which may occasionally occur during complex, multivessel OPCAB. PADCAB promotes collateral myocardial perfusion and avoids the cumulative global effect of sequential episodes of regional ischemia, improving myocardial protection during OPCAB.
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Puente de Arteria Coronaria/métodos , Paro Cardíaco Inducido , Reperfusión Miocárdica , Anastomosis Quirúrgica , Puente Cardiopulmonar , Hemodinámica , Humanos , Daño por Reperfusión Miocárdica/prevención & control , Técnicas de SuturaRESUMEN
BACKGROUND: Outcomes and resource utilization of patients undergoing mitral valve replacement (MVR) with or without concomitant coronary artery bypass grafting (CABG) were reviewed. METHODS: Data for 1,844 patients undergoing isolated primary MVR at Emory University Hospitals between 1980 and 1997 were recorded prospectively in a computerized database. RESULTS: The four groups included patients undergoing elective MVR with (n = 360) or without CABG (n = 1332) and urgent/emergent MVR with (n = 66) or without CABG (n = 86). Length of stay was significantly higher in patients undergoing elective MVR with CABG (15 days) than in those without CABG (11 days) but was not significantly different in patients undergoing urgent/emergent MVR with CABG (17 days) than in those without CABG (19 days). In-hospital mortality was significantly higher for patients undergoing elective (14%) or urgent/emergent (41%) MVR with CABG than in those undergoing MVR without CABG (elective:6%; urgent/emergent:20%). The 19-year survival rate was 32% for patients undergoing elective MVR with CABG compared with 51% for those without CABG and 28% for patients undergoing urgent/emergent MVR with CABG compared with 46% for those without CABG. Multivariate correlates of long-term mortality included older age, concomitant CABG, and urgent/emergent status. Hospital costs were significantly higher for patients undergoing elective MVR with ($33,216) than for those without ($23,890) CABG. No significant difference in cost were noted between patients undergoing urgent/emergent MVR with ($40,535) and without ($31,981) CABG. CONCLUSIONS: The addition of CABG or urgent/emergent status to patients undergoing MVR significantly increases morbidity, mortality, and costs. Careful scrutiny of the benefits versus resource utilization is required for patients undergoing high risk MVR.
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Puente de Arteria Coronaria , Urgencias Médicas , Implantación de Prótesis de Válvulas Cardíacas , Válvula Mitral/cirugía , Puente de Arteria Coronaria/economía , Puente de Arteria Coronaria/mortalidad , Costos y Análisis de Costo , Procedimientos Quirúrgicos Electivos , Femenino , Implantación de Prótesis de Válvulas Cardíacas/economía , Implantación de Prótesis de Válvulas Cardíacas/mortalidad , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Análisis Multivariante , Tasa de SupervivenciaRESUMEN
BACKGROUND: Stroke is a major complication of coronary operation, with reported rates of postoperative cerebral dysfunction ranging from 0.4% to 13.8%. In this report, the incidence, correlates, outcomes, and costs of stroke in coronary operation were evaluated at Emory University between 1988 and 1996. METHODS: Data were entered prospectively into a dedicated computerized database at Emory University and analyzed retrospectively. Univariate and multivariate analyses were utilized where appropriate. RESULTS: Data from 10,860 patients undergoing primary coronary operation between 1988 and 1996 were analyzed. There were 250 patients not entered into the database. Stroke occurred in 244 (2.2%). Univariate predictors of stroke (p<0.05) included age, female gender, hypertension, diabetes, prior stroke, prior transient ischemic attack (TIA), and carotid bruits. Multivariate correlates included age (odds ratio 1.07) previous TIA (odds ratio 2.2), and carotid bruits (odds ratio 1.9), although the area under the Receiver Operating Characteristics (ROC) curve was only 0.69, suggesting limited ability to predict stroke. One and 5 year survival rates were 64% and 44% with stroke, and 94% and 81% without stroke, respectively. Among the stroke group, 23% of the patient population died before hospital discharge. The stroke group had a significantly longer length of hospital stay, as well as higher costs. CONCLUSIONS: Stroke is a devastating complication of coronary operation, significantly increasing morbidity, mortality, and cost. Three independent variables were identified for predicting stroke, including age, previous TIA, and carotid bruits. Patients should be carefully screened for cerebrovascular disease to help prevent stroke and its associated morbidity.
Asunto(s)
Puente de Arteria Coronaria/efectos adversos , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología , Puente Cardiopulmonar , Puente de Arteria Coronaria/economía , Costos y Análisis de Costo , Femenino , Humanos , Incidencia , Masculino , Análisis Multivariante , Factores de RiesgoRESUMEN
BACKGROUND: Hemodynamic instability during multivessel off-pump coronary artery bypass grafting can lead to hypotension, progressive myocardial ischemia, further hypotension, and the need for urgent cardiopulmonary bypass. METHODS: In 10 patients undergoing off-pump coronary artery bypass grafting, a novel technique of pressure-controlled blood delivery has been used that allows the immediate restoration of arterial blood to distal coronary beds after distal coronary anastomosis. This technique utilizes a servo-controlled pump to allow delivery of blood at systemic or suprasystemic pressures, and provides the option for infusion of supplemental additives for myocardial resuscitation, myocardial vasodilation, and enhancement of myocardial performance. RESULTS: Myocardial perfusion was successfully enhanced via one or two grafts in all 10 patients with an average graft flow of 98+/-8 mL/min. In 3 patients, a 27% increase in perfusion pressure led to a 59% increase in perfusate flow. All patients were hemodynamically stable after initiation of selective graft perfusion. CONCLUSIONS: Based on this preliminary patient series, the selective perfusion of grafted vessels seems to facilitate multivessel off-pump coronary artery bypass grafting by promoting rapid recovery of grafted segments, by enhanced hemodynamic stability during subsequent anastomoses, and by providing increased flexibility in the sequence of grafting.
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Puente de Arteria Coronaria/métodos , Circulación Coronaria/fisiología , Perfusión , Anciano , Anastomosis Quirúrgica , Presión Sanguínea/fisiología , Cardiotónicos/uso terapéutico , Vasos Coronarios/fisiopatología , Vasos Coronarios/cirugía , Circulación Extracorporea/instrumentación , Humanos , Hipotensión/etiología , Anastomosis Interna Mamario-Coronaria , Complicaciones Intraoperatorias , Masculino , Persona de Mediana Edad , Contracción Miocárdica/fisiología , Isquemia Miocárdica/etiología , Perfusión/instrumentación , Arteria Radial/trasplante , Vena Safena/trasplante , Vasodilatadores/uso terapéuticoRESUMEN
BACKGROUND: The purpose of this study was to determine whether or not endoscopic vein harvest is a reliable, beneficial, and cost-effective method for saphenous vein harvest in coronary bypass surgery (CABG). METHODS: A total of 100 patients having primary CABG were prospectively randomized to either endoscopic (EVH; n = 47) or open saphenous vein harvest (OVH; n = 50). Three patients in the EVH group required both techniques and were excluded from analysis. RESULTS: The groups did not differ in preoperative characteristics, including: age, gender, left ventricular function, height, weight, percent over ideal body weight, incidence of diabetes, peripheral vascular disease, or preoperative laboratory values (creatinine, albumin, or hematocrit). The EVH group had longer vein harvest and preparation times than the OVH group, while the incision length was significantly shorter. There was no difference between groups in mortality, perioperative myocardial infarction, intensive care unit or postoperative length of stay, blood product utilization, or discharge laboratory measures. There was more drainage noted from leg incisions at hospital discharge in the OVH (34%) versus EVH group (8%; p = 0.001), but more ecchymosis in the EVH group. Although there was a trend towards reduced leg incision pain in the EVH group, there was no statistically significant difference in pain or in the quality of life measure at any point in time. There was no difference between groups in readmission to hospital, administration of antibiotics, or incidence of leg infection. While mean hospital charges for the EVH group were approximately $1,500 greater than for OVH, this difference did not reach statistical significance. CONCLUSIONS: EVH is a safe, reliable, and cost-neutral method for saphenous vein harvest. The best indication for EVH may be in patients who are at increased risk for wound infection and in those for whom cosmesis is a major concern.
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Puente de Arteria Coronaria , Endoscopía , Complicaciones Posoperatorias/etiología , Venas/trasplante , Anciano , Puente de Arteria Coronaria/economía , Análisis Costo-Beneficio , Endoscopía/economía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/economía , Estudios ProspectivosRESUMEN
BACKGROUND: Cardiac valve replacement and coronary artery bypass graft surgery (CABG) are being applied with increasing frequency in patients 80 years of age and older. METHODS: Six hundred one consecutive patients older than 80 years, undergoing cardiac surgery between 1976 and 1994 (CABG with saphenous vein graft, 329 [54.7%]; CABG with left internal mammary artery, 101 [16.8%]; CABG + valve, 80 [13.3%]; isolated aortic valve replacement, 71 [11.8%]; isolated mitral valve replacement, 18 [3.0%]), were studied retrospectively to assess short- and long-term survival. They were compared with 11,386 patients aged 60 to 69 years and 5,698 patients aged 70 to 79 years undergoing similar procedures during the same time interval. RESULTS: In comparison with patients 60 to 69 years old, more octogenarians were women (44.4% versus 25.6%, p<0.0001), had class IV angina (54.1% versus 38.9%, p<0.0001), and had congestive heart failure class IV (4.9% versus 3.0%, p = 0.0001). In-hospital death rates (9.1% versus 3.4%, p<0.0001) and stroke (5.7% versus 2.6%, p<0.0001) reflected these adverse clinical risk factors. However, Q-wave infarction tended to be less frequent (1.5% versus 2.6%, p = 0.102). Interestingly, hospital mortality (9.1% versus 6.7%, p = 0.028) was only slightly increased, and stroke (5.7% versus 4.7%, p = 0.286) was not more common in octogenarians than in patients 70 to 79 years old. Late-survival curves have similar slopes for the first 5 years in all clinical subgroups. However, after 5 years there is a more rapid decline in octogenarians than in younger age groups. Median 5-year survival was 55% for patients older than 80 years, 69% for patients 70 to 79 years, and 81% for patients 60 to 69 years old. CONCLUSIONS: When appropriately applied in selected octogenarians, cardiac surgery can be performed with acceptable mortality and excellent 5-year survival.
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Puente de Arteria Coronaria , Implantación de Prótesis de Válvulas Cardíacas , Anciano , Anciano de 80 o más Años , Angina de Pecho/complicaciones , Trastornos Cerebrovasculares/etiología , Puente de Arteria Coronaria/mortalidad , Femenino , Insuficiencia Cardíaca/complicaciones , Implantación de Prótesis de Válvulas Cardíacas/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del TratamientoRESUMEN
BACKGROUND: This study compared clinical outcomes, length of stay, and hospital costs in patients having off-pump coronary bypass (OPCAB) versus conventional bypass surgery (CABG). METHODS: From November 1996 through April 9, 1999, OPCAB was performed for 125 consecutive patients and compared with a contemporaneous, matched control group of 625 CABG patients. Patients were matched according to age, gender, incidence of renal failure, diabetes, pulmonary disease, stroke (CVA), hypertension, peripheral vascular disease, and previous myocardial infarction. Follow-up in the OPCAB patients was 100% and averaged 15 months. RESULTS: An average of 2.0 grafts per patient were performed in the OPCAB group (range 1-5). Ninety-four OPCAB patients (75.2%) had a total of 179 grafts assessed angiographically prior to hospital discharge. All but 4/179 grafts (2.2%) were patent, including 94 of 94 IMA grafts (100%). There were no in-hospital deaths in the OPCAB group compared to a mortality rate of 1.4% in the CABG group. OPCAB reduced postoperative hospital stay from 5.5 days in the traditional CABG group to 3.3 days (p=.002), with a decrease in hospital cost of 24% (p = .01). In addition, there was a significant reduction in the rate of transfusion in the OPCAB group (29.6%) compared to the CABG group (56.5%, p = .0001). Two OPCAB patients required postoperative intervention to improve graft patency during the follow-up period. No internal mammary grafts required revision. There was one perioperative CVA and one myocardial infarction in the OPCAB group. CONCLUSIONS: OPCAB surgery reduces hospital cost, postoperative length of stay, and transfusion rate compared to CABG. OPCAB is safe, cost effective, and associated with excellent graft patency and clinical outcomes.
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Puente de Arteria Coronaria/métodos , Distribución de Chi-Cuadrado , Angiografía Coronaria , Puente de Arteria Coronaria/economía , Femenino , Costos de Hospital , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Análisis de Regresión , Resultado del Tratamiento , Grado de Desobstrucción VascularRESUMEN
BACKGROUND: Minimally invasive direct coronary artery bypass graft operations have, to date, displayed a higher rate of early graft failure than conventional coronary artery bypass procedures using extracorporeal technology. Construction of the coronary artery anastomosis on a beating heart versus a quiescent heart is likely an important factor in this difference between the two approaches. Controlled intermittent asystole induced by vagal stimulation to give transient nonchemically induced asystole for brief intervals sufficient for placement of coronary artery sutures might improve the precision of minimally invasive direct coronary artery bypass graft anastomoses and reduce graft failure while increasing the technical ease of operation. METHODS: The feasibility of producing transient, reversible asystole with combined vagus nerve stimulation and treatment with a pharmacologic regimen of (1) an acetylcholinesterase inhibitor (pyridostigmine, 0.5 mg/kg), (2) a beta-adrenergic receptor blocker (propranolol, 80 microg/kg), and (3) a calcium-channel blocker (verapamil, 50 microg/kg) was studied in a sheep model. Seven animals underwent right vagus nerve stimulation in two modes: (1) a single continuous 60-second impulse and (2) multiple sequential 15-second impulses. RESULTS: Vagal stimulation alone achieved bradycardia without consistent and reproducible cardiac arrest. After drug administration 6 animals displayed significant potentiation of vagal-induced asystole in the 60-second stimulation protocol (1.6+/-0.9 seconds non-drug-treated versus 52.0+/-5.6 seconds drug-treated; p < 0.05). In the sequential 15-second impulse protocol after drug treatment, 6 animals achieved consistent, escape-free asystole during five to six sequential 15-second stimulations versus a brief pause and bradycardia produced without drug treatment. CONCLUSIONS: Increased acetylcholine activity by acetylcholinesterase inhibition and prevention of electromechanical escape activity by beta-adrenergic receptor and calcium-channel blockade during vagal stimulation produced a marked potentiation of vagal-induced asystole and a means of achieving controlled intermittent asystole. Controlled intermittent asystole achieved by pharmacologic potentiation of vagal-induced asystole may be a useful technique for enhancing technical ease in minimally invasive direct coronary artery bypass graft operations.
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Antagonistas Adrenérgicos beta/farmacología , Bloqueadores de los Canales de Calcio/farmacología , Inhibidores de la Colinesterasa/farmacología , Puente de Arteria Coronaria/métodos , Corazón/efectos de los fármacos , Propranolol/farmacología , Bromuro de Piridostigmina/farmacología , Nervio Vago/fisiología , Verapamilo/farmacología , Animales , Estimulación Eléctrica , Estudios de Factibilidad , Corazón/inervación , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Ovinos , Factores de TiempoRESUMEN
BACKGROUND: In an attempt to avoid the deleterious effects of cardiopulmonary bypass, off-pump coronary artery bypass grafting has been rediscovered and refined. The purpose of this study was to compare clinical outcomes, length of stay, and hospital costs with coronary artery bypass grafting on cardiopulmonary bypass. METHODS: Coronary artery bypass was performed on 51 patients without cardiopulmonary bypass. Patients were selected on the basis of coronary anatomy, with significant stenoses in the left anterior descending, ramus intermedius, diagonal, right coronary, acute marginal, or posterior descending territories. Outcomes were compared with those of a computer-generated matched control group having coronary artery bypass grafting on cardiopulmonary bypass (n = 248) during the same time period. RESULTS: No preoperative differences were noted between groups. There were no deaths in the off-pump group and a mortality rate of 1.6% (4/248) in the control group. There was no incidence of stroke, myocardial infarction, or reentry for bleeding among patients in the off-pump group. There was a reduction in length of stay by 3 days (p = 0.01), blood transfusions by 50% (p = 0.0001), and hospital charges by one third (p = 0.05) in the off-pump group. Twenty-six patients had repeat coronary angiography before discharge; 41/43 grafts were widely patent, 1/43 was totally occluded, and 1/43 was narrowed by more than 50%. All internal mammary artery grafts were widely patent. CONCLUSIONS: Off-pump multivessel cardiopulmonary bypass grafting is a safe and effective means of revascularization for patients with coronary stenoses in the anterior or inferior regions, with excellent short-term patency rates and minimal morbidity.
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Puente de Arteria Coronaria/métodos , Enfermedad Coronaria/cirugía , Transfusión Sanguínea , Estudios de Evaluación como Asunto , Femenino , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Análisis de Regresión , Esternón/cirugía , Resultado del TratamientoRESUMEN
Successful management of chronic postoperative bronchopleural fistula remains a challenge for thoracic surgeons. Forty-two patients (33 referred from other institutions) were treated for major postoperative bronchopleural fistula since 1978. Factors associated with bronchopleural fistula included right pneumonectomy (n = 23), left pneumonectomy (n = 8), long bronchial stump (n = 16), pneumonia (n = 13), radiation therapy (n = 12), stapled bronchial closure (n = 8), prolonged mechanical ventilation (n = 7), recurrent carcinoma (n = 6), and tuberculosis (n = 2). Patients had undergone an average of 3.3 surgical procedures to correct their bronchopleural fistulas during a mean interval of 24 months before our treatment. Bronchopleural fistulas were located in the right main bronchial stump (n = 23), left main bronchial stump (n = 8), right lobar bronchial stumps (n = 10), and tracheobronchial anastomosis (n = 1). Thirty-five patients were treated by suture closure of the bronchial stump, buttressed with vascularized pedicle flaps of omentum (n = 19), muscle (n = 13), or pleura (n = 2). In seven cases, direct suture closure was not possible, and omental (n = 6) or muscle (n = 1) flaps were sutured over the bronchopleural fistula. Suture closure without pedicle coverage was performed successfully in one case. Initial repair of the fistula was successful in 23 of 25 patients treated with omentum, in nine of 14 patients treated with muscle and in neither of two patients treated with pleural flaps. In nine patients with persistent or recurrent bronchopleural fistula after our initial repair, four underwent a second procedure (three successful) and five were managed with drainage only. The fistula was successfully closed in 11 of 12 patients who had received high-dose radiation therapy (nine with omentum). Overall, successful closure of bronchopleural fistula was achieved in 36 of 42 patients (86%). Four in-hospital deaths resulted from pneumonia and sepsis, two in patients with recurrent bronchopleural fistula after pleural flap closure. In 16 patients the empyema cavity was obliterated during definitive repair of the fistula. The cavity resolved with drainage in four others, nine had draining cavities at follow-up, and one was lost to follow-up. Ten patients required a total of 17 Clagett procedures and one had a delayed myoplasty. Direct surgical repair of chronic bronchopleural fistula may be achieved in most patients after adequate pleural drainage by suture closure and aggressive transposition of vascularized pedicle flaps. Omentum is particularly effective in buttressing the closure of bronchopleural fistulas.
Asunto(s)
Fístula Bronquial/cirugía , Fístula/cirugía , Enfermedades Pleurales/cirugía , Adulto , Anciano , Empiema/cirugía , Femenino , Humanos , Masculino , Métodos , Persona de Mediana Edad , Recurrencia , Colgajos QuirúrgicosRESUMEN
Exposure of animals to transient hyperthermia causes the induction of highly conserved proteins, heat shock proteins (HSPs), which are thought to by cytoprotective against a variety of injuries, including ischemia. We tested the hypothesis that heating donor animals prior to harvest would improve pulmonary preservation. Anaesthetized New Zealand White rabbits underwent radiant heating to 42.5-43.5 degrees C (rectal) 8 h prior to harvest of the lungs. The lungs were harvested without flush and stored for 18 h at 4 degrees C. The left lung were perfused ex vivo with fresh blood for 10 min. Blood gases, pulmonary artery (Ppa) and airway (P(aw) pressures, and wet/dry ratios (W/D) were measured. Control animals were treated identically except without heating. All heated animals had HSP72 at lung harvest and 18 h later, whereas no control had detectable levels of HSP72 at either time. In Experiment 1 (n = 12, VT 20 ml, F1O2 0.21, 30 bpm, PEEP 0.5 cm H2O), PO2 in the heated group was 57.6 +/- 7.3 mmHg (mean +/- SEM) vs. 51.6 +/- 5.7 in the controls (NS). In Experiment 2 (n = 8, VT 15 ml, F1O2 0.21, 35 bpm, PEEP 2 cm H2O), PO2 of the heated group was 63.5 +/- 6.5 vs. 83.1 +/- 9.5 in the controls (NS). Ppa after 10 min was not significantly different in the heated group in Experiment 1 (16.7 +/- 0.9 mmHg vs. 24.2 +/- 3.7 in controls) or in Experiment 2 (19.5 +/- 1.8 vs. 11.3 +/- 2.9 in controls). Wet/dry ratios were not different in either Experiment 1 (6.4 +/- 0.4 vs. 5.8 +/- 0.2 in controls) or Experiment 2 (5.0 +/- 0.2 vs. 5.0 +/- 0.5).(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Hipertermia Inducida , Pulmón/fisiología , Preservación de Órganos , Animales , Criopreservación , Proteínas del Choque Térmico HSP72 , Proteínas de Choque Térmico/biosíntesis , Calor , ConejosRESUMEN
Placement of central venous catheter is the most common cause of subclavian vein thrombosis. In the setting of a functioning ipsilateral brachial arteriovenous fistula, venous hypertension symptoms may be exacerbated. We report successful decompression of severe venous hypertension in the right arm of a patient whose only access for hemodialysis was a functioning right brachial arteriovenous fistula and in whom proximal subclavian vein occlusion developed from a previous percutaneous dialysis catheter. Transposition of the right internal jugular vein and end-to-side anastomosis to the right axillary vein provided prompt and effective venous outflow, with complete resolution of venous engorgement of the affected limb and preservation of the dialysis fistula.
Asunto(s)
Derivación Arteriovenosa Quirúrgica/efectos adversos , Vena Axilar/cirugía , Antebrazo/irrigación sanguínea , Venas Yugulares/cirugía , Complicaciones Posoperatorias/cirugía , Diálisis Renal/efectos adversos , Vena Subclavia/cirugía , Trombosis/cirugía , Cateterismo Venoso Central/efectos adversos , Femenino , Humanos , Hipertensión/etiología , Hipertensión/cirugía , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Trombosis/etiologíaRESUMEN
We sought to reduce early ischemia-reperfusion injury after lung preservation by an initial brief period of hemodilute reperfusion. Left lungs of New Zealand White rabbits were ventilated with room air and reperfused in an ex vivo ventilation-perfusion apparatus after 18 hours of storage at 10 degrees C. Lungs were randomly assigned to one of three groups (n = 6) according to the composition of initial reperfusate. In group 1 (control), preserved lungs were reperfused with whole blood for 20 minutes (hematocrit, 38%). In the experimental groups, blood was diluted to a hematocrit of 10% with Ringer's lactate (group 2) or low-potassium-dextran solution (group 3) for the first 10 minutes of reperfusion, followed immediately by whole blood for 10 minutes. Oxygen tension of left ventricular effluent at the end of the 20-minute assessment period was significantly higher in both hemodiluted groups (mean +/- standard error of the mean: group 2, 81.3 +/- 6.6 mmHg; group 3, 77.0 +/- 9.5 mmHg, versus Group 1, 46.3 +/- 7.4 mmHg; p < 0.006). Similarly, mean tracheal airway pressure was reduced in the hemodiluted groups, suggesting improved compliance (group 2; 3.1 +/- 0.3 mmHg; group 3, 2.8 +/- 0.6 mmHg; versus group 1, 6.5 +/- 1.4 mm Hg; p < 0.05). An initial 10-minute period of hemodilute reperfusion appears to reduce early pulmonary ischemia-reperfusion injury in this 18-hour ex vivo rabbit lung preservation model.
Asunto(s)
Hemodilución , Pulmón , Preservación de Órganos , Daño por Reperfusión/prevención & control , Resistencia de las Vías Respiratorias , Animales , Hematócrito , Técnicas In Vitro , Pulmón/irrigación sanguínea , Rendimiento Pulmonar , Modelos Biológicos , Conejos , Distribución Aleatoria , Reperfusión/métodos , Daño por Reperfusión/fisiopatologíaRESUMEN
To reduce ischemia-reperfusion injury, a number of clinical lung transplant programs employ prostaglandin E1 (PGE1) or prostacyclin (PGI2) before donor lung flush and harvest. The effect of prostaglandins on the reperfusion component of this ischemia-reperfusion complex is unknown. We investigated the effect of PGE1 given only during the period of reperfusion, on ischemic lung injury in an in situ rabbit model. To examine the mechanisms involved, we measured pulmonary hemodynamics as well as myeloperoxidase, circulating platelet, and tumor necrosis factor (TNF) values. Two hours of warm ischemia of the left lung was produced in anesthetized New Zealand white rabbits. The animals were randomly allocated into four groups based on treatment received only during reperfusion: PGE1, PGI2, nitroprusside (NP), or no treatment (controls). After 2 h of reperfusion, PaO2 in the PGE1 group was significantly higher (423 +/- 52.7 mm Hg) than in all other groups (PGI2, 239 +/- 43.4, p < 0.05; NP, 146 +/- 14.2 p < 0.01; controls, 74 +/- 19.1 mm Hg, p < 0.01), despite similar pulmonary vascular resistance in the PGE1 and NP groups. Although lower than in the PGE1 group, PaO2 in the PGI2 group was still significantly higher than that in controls. Wet/dry lung weight ratios were significantly lower in the PGE1 and PGI2 groups (6.5 +/- 0.2 [p < 0.01] and 6.9 +/- 0.6 [p < 0.05], respectively, versus 8.2 +/- 0.1 in controls). There were no significant differences in plasma TNF levels, platelet sequestration across the lungs, or lung myeloperoxidase activity in the four groups.(ABSTRACT TRUNCATED AT 250 WORDS)