RESUMEN
Resumen: Objetivo: Describir la participación de los exámenes de imagen en el Régimen de Garantías Explícitas en Salud en Chile y analizar el papel de los radiólogos en este campo. Materiales y métodos: todas las patologías incluidas en el Programa de garantías explícitas en salud, cuentan con una guía de práctica clínica (GC) y un listado de prestaciones específicas (LP). Ambos fueron analizados respecto a la cantidad y la modalidad de los exámenes de imagen recomendados, la presencia de radiólogos dentro de los paneles de expertos y la concordancia entre las recomendaciones de las guías y los Listados de Prestaciones. Resultados: 60 GC (67%) y 55 LP (69%) incluyen pruebas de imagen dentro de sus prestaciones garantizadas. 7 GC (8%) recomiendan pruebas de imágenes no cubiertas en su listado de prestaciones respectivos y 5 pruebas de imágenes del LP (6%) no están incluídas en las guías clínicas. La participación de un radiólogo en el panel de expertos se asoció con la ausencia de discrepancias en las pruebas de imagen entre GC y LP (p = 0,007). Discusión: el diagnóstico por imágenes juega un papel importante dentro del Programa de garantías explícitas y se asocia al aumento de los costos de atención médica. Algunos casos de discordancia entre las guías clínicas y los Listados de Prestaciones representan costos económicos y sociales significativos que podrían reducirse al incluir radiólogos en los paneles de expertos, así como optimizar el uso de recursos y reducir la exposición de los pacientes a la radiación ionizante.
Abstract: Objective: To describe the involvement diagnostic imaging exams in the framework of Regime of Explicit Health Guarantees in Chile and analyze the role of radiologists in this field. Materials and methods: Every pathology included in the Explicit Healthcare Guarantees Program encompasses an expert consensus clinical guideline (CG) and a specific services list (SL). Both of them were analyzed regarding the amount and modality of imaging exams recommended, the presence of radiologists within the expert panels and the concordance between guidelines recommendations and service lists. Results: 60 CG (67%) and 55 SL (69%) include imaging tests within their guaranteed services. Seven CG (8%) recommend medical imaging tests not covered in their respective services list and 5 SL (6%) reference imaging tests not included in the clinical guidelines. The involvement of a radiologist on the expert panel was associated with the absence of imaging test discrepancies between CG and SL (p=0.007). Discussion: Diagnostic imaging plays an important role within the Explicit Healthcare Guarantees Program and is associated with rising healthcare costs. There are cases of discordance between clinical guidelines and specific services lists that account for significant economic and social costs, which may be reduced by including radiologists on expert panels, optimizing resource use and lowering patients' exposure to ionizing radiation.
Asunto(s)
Humanos , Rol del Médico , Diagnóstico por Imagen/estadística & datos numéricos , Planes y Programas de Salud , Diagnóstico por Imagen/economía , Diagnóstico por Imagen/normas , Chile , Costos de la Atención en Salud , Guías de Práctica Clínica como Asunto , Atención a la Salud , Radiólogos/provisión & distribuciónRESUMEN
Background: Problems associated with alcohol consumption are prevalent in Chile, but little is known about the situation in the elderly. Aim: To perform a screening to detect alcohol-related problems and risks in the Chilean older people who travel. Material and Methods: The Alcohol Use Disorders Identification Test (AUDIT) questionnaire was answered by 1,076 travelers aged 60 to 93 years (66% females), who participated in trips organized by the Chilean National Tourism Service (SERNATUR). Results: Seventy six percent of respondents acknowledged to have ingested an alcoholic drink during the last month. The average AUDIT score was of 2.2 ± 2.6. Only 3.7% of the sample had a score equal or higher than eight, considered as risky use. Within this last group, 60% had symptoms of alcohol dependence. A higher alcohol consumption was associated with male gender (p < 0.01), being younger than 75 years of age (p < 0.01), having a medium-low economic income (p < 0.01) and having a higher education level (p = 0.03). There was no significant association with the respondents´ occupation. Conclusions: In this sample of Chilean traveling older people, there was a high prevalence of alcohol consumption, and nearly 4% of respondents had alcohol related problems.
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Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Consumo de Bebidas Alcohólicas/epidemiología , Trastornos Relacionados con Alcohol/epidemiología , Viaje , Factores de Edad , Trastornos Relacionados con Alcohol/diagnóstico , Chile/epidemiología , Prevalencia , Factores Sexuales , Factores SocioeconómicosRESUMEN
The echocardiographic identification of cardiac tumors as cause of embolic episodes is infrequent, and the finding of multiple papillary fibroelastoma is even less common. We report a 70 years old female with a history of a rheumatic mitral valve lesion, subjected to a commissurotomy in 1970. She was admitted with a cerebrovascular accident and the transesophageal echocardiogram revealed the presence of a multiple papillary fibroelastoma in the aortic valve. The patient was operated and the tumor excised, the pathological analysis confirmed the diagnosis. The patient was discharged in good conditions and after 8 months of follow up, she has no neurological abnormality and is in functional class I.
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Fibroma/patología , Neoplasias Cardíacas/patología , Accidente Cerebrovascular/patología , Anciano , Ecocardiografía Transesofágica , Femenino , Fibroma/etiología , Fibroma/cirugía , Neoplasias Cardíacas/etiología , Neoplasias Cardíacas/cirugía , Humanos , Embolia Intracraneal/patología , Accidente Cerebrovascular/complicacionesRESUMEN
BACKGROUND: Few data exist regarding angiographic predictors of radial artery patency for coronary bypass grafting, and the benefit of calcium antagonists is not clear. METHODS: One hundred fifteen patients were studied who had myocardial revascularization with the radial artery plus internal mammary and vein grafts with 3.5 +/- 1.1 grafts per patient. Sixty-three patients received diltiazem and 52 patients did not. Base line and follow-up angiographies were analyzed 1 year postoperatively in 50 of these patients with a quantitative computerized method. RESULTS: One hundred fourteen patients survived and were followed for 30.1 +/- 12.6 months. Patency for mammary grafts was 100%, for radial grafts it was 80%, and for saphenous vein grafts it was 68%. Patent radial artery grafts had significantly greater degree of stenosis in the native vessels than occluded grafts (73% +/- 14% vs 40% +/- 24%), (p = 0.0007; confidence interval = 95%). Radial artery patency increased to 92% when arteries with 70% or more stenosis were considered. No differences were observed for clinical and angiographic end points in the patients that received diltiazem compared with the rest who had not. CONCLUSIONS: The degree of stenosis in the native coronary artery significantly influences the patency rate of radial artery grafts, independent of diltiazem.
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Puente de Arteria Coronaria , Arteria Radial/trasplante , Grado de Desobstrucción Vascular , Adulto , Anciano , Femenino , Estudios de Seguimiento , Humanos , Masculino , Arterias Mamarias/trasplante , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Vena Safena/trasplanteRESUMEN
Mediastinitis with graft infection is a serious complication of ascending aorta replacement. We report two cases of graft infection, treated with surgical cleaning, graft preservation and transposition of muscle flaps. A 62 years old male was admitted 34 days after an ascending aortic grafting due to a sternal dehiscence and mediastinitis. Antimicrobial treatment was started and a surgical cleaning performed, leaving an open sternotomy. Three days later, the thoracic cavity was closed with a rectus abdominis muscle flap. After 23 months of follow up, the patient is well and without evidence of infection. A 74 years old male was subjected to an aortic valve and ascending aorta replacement and a myocardial revascularization. In the postoperative period, the patient developed septic signs, and a purulent drainage. A CAT scan showed a liquid collection surrounding the aortic graft. On tW Sixteenth postoperative day, a surgical cleaning was performed and the thorax was closed with the pectoralis major muscle. After 10 months of follow up, the patient is in Good condition and without evidence of infection.
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Aorta/trasplante , Prótesis Vascular/efectos adversos , Mediastinitis/cirugía , Infecciones Relacionadas con Prótesis/cirugía , Colgajos Quirúrgicos , Anciano , Humanos , Masculino , Persona de Mediana Edad , Infecciones por Pseudomonas/microbiología , Infecciones Estafilocócicas/microbiología , Tomografía Computarizada por Rayos XRESUMEN
The first surgical procedure for the treatment of coronary artery disease, in 1933, was total thyroidectomy. Some years later, procedures to increase heart irrigation such as pectoral or great epiplon grafting and cardiopeumopexy were attempted. In 1940, the ligation of great cardiac vein or coronary sinus were introduced. Five years later, pericoronary neurectomy was used. In 1945, Beck used an arteriovenous fistula between the descending aorta and the coronary sinus and, from 1954, be used the erosion of heart surface with asbestos application, complemented with the occlusion of the coronary sinus and the application of parietal pericardium. In 1958, Glover introduced the bilateral ligation of mammary arteries and Vineberg, developed the internal mammary artery implant, that consisted in the tunneling of the free portion of such artery in the myocardium. En 1956, Lillehei and Bailey introduced coronary endarterectomy and finally in 1967, Favaloro introduced systematically the aortocoronary bypass using saphenous vein, that became the definitive surgical treatment for coronary artery disease. In Chile the first coronary surgery was done by Torwall and Uribe in 1950 and modern coronary surgery was initiated by Salvestrini in 1970.
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Procedimientos Quirúrgicos Cardiovasculares/historia , Enfermedad Coronaria/historia , Chile , Enfermedad Coronaria/cirugía , Historia del Siglo XX , HumanosRESUMEN
BACKGROUND: Heart transplantation currently provides the most effective treatment for advanced heart failure. However, medical therapy for this condition has also improved, heart donors are scarce and the cost of the procedure is high. Therefore the indications and management of these patients need reevaluation. AIM: To analyze the results of 24 patients submitted to heart transplantation for end-stage heart failure needing repeated hospitalizations and i.v. inotropes for compensation. PATIENTS AND METHODS: The group was comprised by 21 men and 3 women with a mean age of 36.8 years, mean left ventricular ejection fraction 19 +/- 4.5%, mean systolic pulmonary artery pressure 48 +/- 13 mmHg (24-70) and mean pulmonary vascular resistance 2.6 Wood Units (1-5). Fourteen patients (58%) had a previous median sternotomy. Immunosuppression did not include induction therapy and steroids were discontinued early. RESULTS: Operative mortality was 4% at 30 days. Actuarial survival at one year was 90% and at 5 years 72%. Freedom from rejection at one year was 76% and at 5 years 50%. Freedom from infection was 70% at one year and 56.5% at five years. All patients with more than 3 months of follow-up were in functional class I. CONCLUSIONS: These results justify the proposed modifications for transplantation protocols.
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Insuficiencia Cardíaca/cirugía , Trasplante de Corazón/métodos , Análisis Actuarial , Adolescente , Adulto , Protocolos Clínicos , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Rechazo de Injerto/tratamiento farmacológico , Rechazo de Injerto/inmunología , Humanos , Terapia de Inmunosupresión/métodos , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
BACKGROUND: Coronary artery bypass grafting (CABG) reoperation is being performed with increasing frequency. AIM: To assess the early and long term results of coronary reoperations in our institution and to identify prognostic factors. PATIENTS AND METHODS: 214 patients subjected to coronary reoperations between 1983 and 1999 were retrospectively studied. RESULTS: Mean age was 64.2 years (range 42-79 years), 202 (94.4%) were male and 12 (5.6%) female. The mean interval between the operations was 125.7 months (range 6-252 months). 10 (4.6%) were emergency surgeries. Overall operative mortality was 5.6% (11 deaths) and in 5 patients (3.4%) a perioperative myocardial infarction was noted. Univariate analysis identified moderate or severe left ventricular failure (p = 0.048) as predictor of increased operative mortality, meanwhile age over 75 years (p = 0.02) and moderate or severe left ventricular failure (p = 0.01) were identified as predictors of increased in hospital mortality in the multivariate analysis. Follow up of in hospital survivors (mean interval 65 months, range 4 to 190 months) documented a 5 years survival rate of 82.9%, a 10 years survival rate of 73.1% and a 15 years survival rate of 53.4%. Moderate or severe left ventricular failure (p < 0.0001) and emergency surgeries (p = 0.007) were identified as factors influencing the late survival in the stepwise logistical regression analysis. Multivariate analysis identified left ventricular failure (p = 0.01) and peripheral vascular disease (p = 0.01) as predictors of decreased late survival. CONCLUSIONS: Coronary reoperation has a low mortality in patients with a normal ventricular function and also has an excellent overall and disease free survival in the first 10 years of follow up. Left ventricular function is an independent risk factor increasing in hospital and late mortality.
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Puente de Arteria Coronaria , Enfermedad Coronaria/cirugía , Adulto , Anciano , Chile/epidemiología , Enfermedad Coronaria/mortalidad , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Reoperación , Estudios Retrospectivos , Factores de RiesgoRESUMEN
BACKGROUND: It is known that the sympathetic varicosities co-store and co-release norepinephrine (NE) together with adenosine S-triphosphate (ATP) and neuropeptide Y (NPY). AIM: To describe the chemical characterization of stored and released NPY from the varicosities of sympathetic nerve terminals surrounding segments of the human saphenous vein, and the vasomotor activity of rings electrically depolarized or contracted by the exogenous application of the co-transmitters. MATERIAL AND METHODS: Saphenous vein tissues were obtained from patients undergoing elective cardiac revascularization surgery. RESULTS: The chromatographic profile of NPY extracted from biopsies is identical to a chemical standard of human NPY. Upon electrical depolarisation of the perivascular sympathetic nerve terminals, we demonstrated the release of NPY to the superfusion media, which did not exceed a 1% of its stored content. The release of the peptide is sensitive to guanethidine, and to extracellular calcium, suggesting that the mechanism of its release is exocytotic in nature. The electrically evoked release of NPY is dependent on the frequency and duration of the electrical pulses. Phenoxybenzamine reduces the electrically evoked release of NPY. Exogenous application of NE and ATP contract saphenous vein rings; the simultaneous application of NE plus ATP causes a synergic response, effect which is further potentiated by the joint co-application of 10 nM NPY. CONCLUSIONS: Present results highlight the role of NPY as a sympathetic co-transmitter in the regulation of human vascular tone.
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Adenosina Trifosfato/farmacología , Neuropéptido Y/fisiología , Vena Safena/inervación , Transmisión Sináptica/fisiología , Estimulación Eléctrica , Humanos , Neuropéptido Y/análisis , Neuropéptido Y/farmacología , Neurotransmisores/farmacología , Norepinefrina/farmacología , Sistema Nervioso Periférico/efectos de los fármacos , Vena Safena/química , Vena Safena/efectos de los fármacos , Transmisión Sináptica/efectos de los fármacos , Resistencia VascularRESUMEN
BACKGROUND: Early diagnosis, an effective treatment and prompt recognition of complications are essential to improve the prognosis of infective endocarditis (IE). AIM: To report the results of a multidisciplinary approach to diagnosis and management of patients with IE at the Universidad Católica de Chile Hospital. PATIENTS AND METHODS: The clinical history, diagnosis, treatment and outcome of 261 episodes (Duke criteria) of IE admitted between January 1980 and January 1999 were analyzed. These included 185 episodes of native, 73 of prosthetic valve and 3 of nonvalvular IE. RESULTS: Sixty nine percent of patients were men and the mean age was 49 +/- 16 years. Seventy five percent had a definite diagnosis of IE (Duke). S. viridans, staphylococci and enterococci together constituted 85% of the isolated bacterial strains. Twenty seven had culture-negative IE, related to a high incidence of antibiotic therapy prior to diagnosis. Transesophageal echocardiography was performed in 102 cases and it detected vegetations in 91% of aortic and 96% of mitral IE, rupture or prosthesis dehiscence in 67% of aortic and 52% of mitral IE and abscesses in 51% of aortic and 15% of mitral IE. Fifty one percent developed heart failure and 34% had embolic events. S. aureus IE was associated to a higher incidence of embolic events, complications which contraindicated surgery and increased mortality rate (27%). Of all patients, 40% were treated exclusively with antibiotics, 52% were operated on and 8% had surgical indication but were nonoperable because of serious complications. The overall mortality was 16.3%: 13% in the medical, 9% in the surgical and 81% in the non-operable groups. The type of treatment and mortality rates did not differ between IE of native valves and prosthetic valves. Long term follow up showed survival rates of 73% at 5 years and 66% at 10 years. CONCLUSION: A multidisciplinary approach may be very helpful to improve the prognosis of IE.
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Endocarditis Bacteriana/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Endocarditis Bacteriana/complicaciones , Endocarditis Bacteriana/mortalidad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Grupo de Atención al Paciente , Pronóstico , Estudios Prospectivos , Tasa de Supervivencia , Resultado del TratamientoRESUMEN
This study was designed to evaluate efficacy and tolerability of two different doses of aprotinin in patients receiving aspirin before undergoing coronary artery bypass grafting. Forty-two patients were randomized to receive either placebo (group I), or aprotinin in doses of 4,000,000 KIU (group II) or 6,000,000 KIU (group III). Drug efficacy was determined by measuring postoperative blood loss and transfusion of blood products. Both doses were effective in reducing blood loss and transfusion requirements. Blood loss through thoracotomy drainage was 450 +/- 224, 182 +/- 144, 142 +/- 98 ml, respectively, for control and treatment groups II and III (p = 0.0001). The numbers of patients with blood transfusions were seven (50%), two (17%) and two (17%) for group I and treatment groups II and III, respectively (p = 0.10). Tolerability was excellent and complications few and reversible. In conclusion, high and medium doses of aprotinin were well tolerated and reduced bleeding and transfusion requirements in patients submitted to coronary bypass surgery under the effects of aspirin.
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Aprotinina/administración & dosificación , Aspirina/administración & dosificación , Pérdida de Sangre Quirúrgica/prevención & control , Puente Cardiopulmonar , Puente de Arteria Coronaria , Hemostáticos/administración & dosificación , Inhibidores de Agregación Plaquetaria/administración & dosificación , Premedicación , Adulto , Anciano , Aprotinina/uso terapéutico , Aspirina/efectos adversos , Aspirina/uso terapéutico , Transfusión Sanguínea/estadística & datos numéricos , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Drenaje , Femenino , Hemostáticos/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Inhibidores de Agregación Plaquetaria/efectos adversos , Inhibidores de Agregación Plaquetaria/uso terapéutico , Hemorragia Posoperatoria/prevención & control , Periodo Posoperatorio , Estudios Prospectivos , Seguridad , Toracotomía , Resultado del TratamientoRESUMEN
INTRODUCTION AND OBJECTIVES: To establish the results obtained with the classical technique of mammary anastomosis of the anterior descending artery. MATERIALS AND METHODS: Between January 1982 and July 1997, 154 patients received an anastomosis of the left internal mammary artery to the left anterior descending coronary artery with use of the classical technique (sternotomy and extracorporeal circulation). RESULTS: There was no operative mortality in our group, nor paraoperational myocardial infarction, nor cephalic vascular accidents. One (0.6%) patient had sternal wound infection, and another (0.6%) required another reoperation for postoperational bleeding. All (100%) were followed-up from 3-183 months (average 64. 4 months). Actuarial global survival at 5, 10 and 15 years was 95.6%+/-2.1; 92.1%+/-4 and 85.5+/- 7.5 respectively, and the actuarial probability of being free from cardiac death was 99%+/-0.9; 99% and 99%. The actuarial probability of being free from myocardial infarction was 99%+/-0.9; 99%+/-0.9 and 99%; and from angina was 95%+/-2.2; 86.9%+/-4.9 and 74.5%+/-12.2 at 5, 10 and 15 years.Finally, the actuarial probability of being free from reoperation was 99%+/-0.9; 99%; 99% and from angioplasty 96.9%+/-1.7; 91.4%+/-4.1; 91.4%+/-4.1 at 5, 10 and 15 years, respectively. The average hospital charges in the last 10% of the patients was U$ 6.200. CONCLUSIONS: Revascularization of the left anterior descending with the left internal mammary artery and the classical technique (sternotomy and extracorporeal circulation) is a safe, minimal risk, effective, long lasting and cost efficient procedure with excellent results at 10 and 15 years.
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Anastomosis Interna Mamario-Coronaria/métodos , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad Coronaria/mortalidad , Enfermedad Coronaria/cirugía , Circulación Extracorporea , Femenino , Estudios de Seguimiento , Humanos , Anastomosis Interna Mamario-Coronaria/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
Heart transplantation is a therapeutic alternative for selected patients with refractory heart failure. Acute allograft rejection is one of the main causes of early death after transplantation. The cellular rejection is characterized by cellular infiltrates with or without myocyte necrosis. However, some patients develop left ventricular dysfunction due to rejection without evidence of cellular infiltration. In these patients, the rejection is mediated by antibodies and complement. Humoral rejection is a relative rare but potentially fatal form of acute allograft rejection. We report two patients with left ventricular dysfunction secondary to humoral rejection, shortly after cardiac transplantation. Both patients were treated with methylprednisolone, and azathioprine was substituted by cyclophosphamide. One patient underwent plasmapheresis. The clinical outcome was satisfactory and the left ventricular function returned to normal in both cases. The diagnostic and therapeutic strategies for the management of humoral rejection are reviewed.
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Rechazo de Injerto/inmunología , Trasplante de Corazón/inmunología , Disfunción Ventricular Izquierda/inmunología , Formación de Anticuerpos/inmunología , Rechazo de Injerto/diagnóstico , Rechazo de Injerto/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana EdadRESUMEN
BACKGROUND: Continuous improvement of dual chamber DDD pacemakers, electrode stability and programmed sequential stimulation changed the prognosis of patients implanted with these devices. AIM: To report our experience with the use of dual chamber pacemakers. MATERIAL AND METHODS: One hundred seventy six patients (116 male), aged 13 to 91 years old, who received a dual chamber pacemaker implant, are reported. Patients were followed for a mean of 2.6 years. RESULTS: Indications for DDD pacemaker were complete atrioventricular block in 43%, sick sinus syndrome in 32%, paroxysmal A-V block in 24%. All pacemakers were Siemens-Pacesetter and were provided with an automatic sensing and threshold device. J shaped atrium electrodes were used in 78% of patients and screw-in electrodes in 22%. Post operative complications were displacement of atrial electrode in 8 patients, of ventricular electrode in 6 patients, infection in two patients and a hematoma in one. Chronic parameters, measured after six months, were within expected ranges and allowed a good reprogramming of pacemakers. Long term programming aimed to reduce battery depletion, enhance device performance and improve hemodynamic conditions. Normal sequential stimulation was achieved in 154 patients (87%), 14 (85) patients died of cardiovascular disease not related to pacemaker function. Eight patients were in atrial fibrillation and were reprogrammed to VVI and DDI modes. CONCLUSIONS: DDD pacemakers are reliable and afford symptomatic relief in a broad spectrum of patients.
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Estimulación Cardíaca Artificial/métodos , Enfermedades Cardiovasculares/terapia , Marcapaso Artificial , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Arritmia Sinusal/terapia , Femenino , Estudios de Seguimiento , Bloqueo Cardíaco/terapia , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo , Resultado del TratamientoRESUMEN
BACKGROUND: There is a growing interest to perform a left internal mammary artery (LIMA) graft to the left anterior descending coronary artery (LAD) on a beating heart through a minimally invasive access to the chest cavity. AIM: To report the experience with minimally invasive coronary artery surgery. PATIENTS AND METHODS: Analysis of 11 patients aged 48 to 79 years old with single vessel disease that, between 1996 and 1997, had a LIMA graft to the LAD performed through a minimally invasive left anterior mediastinotomy, without cardiopulmonary bypass. A 6 to 10 cm left parasternal incision was done. The LIMA to the LAD anastomosis was done after pharmacological heart rate and blood pressure control and a period of ischemic pre conditioning. Graft patency was confirmed intraoperatively by standard Doppler techniques. Patients were followed for a mean of 11.6 months (7-15 months). RESULTS: All patients were extubated in the operating room and transferred out of the intensive care unit on the next morning. Seven patients were discharged on the third postoperative day. Duplex scanning confirmed graft patency in all patients before discharge; in two patients, it was confirmed additionally by arteriography. There was no hospital mortality, no perioperative myocardial infarction and no bleeding problems. After follow up, ten patients were free of angina, in functional class I and pleased with the surgical and cosmetic results. One patient developed atypical angina on the seventh postoperative month and a selective arteriography confirmed stenosis of the anastomosis. A successful angioplasty of the original LAD lesion was carried out. CONCLUSIONS: A minimally invasive left anterior mediastinotomy is a good surgical access to perform a successful LIMA to LAD graft without cardiopulmonary bypass, allowing a shorter hospital stay and earlier postoperative recovery. However, a larger experience and a longer follow up is required to define its role in the treatment of coronary artery disease.
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Enfermedad Coronaria/cirugía , Procedimientos Quirúrgicos Mínimamente Invasivos , Procedimientos Quirúrgicos Vasculares/métodos , Adulto , Anciano , Femenino , Estudios de Seguimiento , Humanos , Anastomosis Interna Mamario-Coronaria , Masculino , Persona de Mediana Edad , Resultado del TratamientoRESUMEN
1. Human saphenous veins were used to assess the cooperative participation of adenosine 5-triphosphate (ATP), neuropeptide Y (NPY), and noradrenaline (NA) in the vasomotor responses elicited following electrical depolarization of the perivascular nerve terminals. Rings from recently dissected human biopsies were mounted to record isometric muscular contractions; the motor activity elicited in the circular muscle layer following electrical depolarization (2.5-20 Hz, 50 V, 0.5 msec) were recorded. 2. Incubation of the biopsies with either 100 nM tetrodotoxin (TTX) or 1 microM guanethidine abolished the vasomotor response elicited by electrical nerve depolarization. The independent application of either ATP or NA to vein rings induced concentration-dependent contractions. 3. Tissue incubation with 30 microM suramin or 10 nM prazosin produced 10 fold rightward displacements of the alpha,beta-methylene ATP and NA concentration-response curves respectively. NPY contracted a limited number of biopsies, the vasoconstriction elicited was completely blocked by 1 microM BIBP 3226. A 5 min incubation of the biopsies with 10-100 nM NPY synergized, in a concentration-dependent fashion, both the ATP and the ATP analogue-induced contractions. Likewise, tissue preincubation with 10 nM NPY potentiated the vasomotor responses evoked with 20-60 nM NA. 4. Neither suramin, BIBP 3226, nor prazosin was individually able to significantly modify the derived frequency-tension curves. In contrast, the co-application of 30 microM suramin and 10 nM prazosin or 30 microM suramin and 1 microM BIBP 3226, elicited a significant (P<0.01) downward displacement of the respective frequency-tension curves. 5. The simultaneous application of the three antagonists-30 microM suramin, 1 microM BIBP 3226 and 10 nM prazosin-caused a significantly greater displacement of the frequency-tension curve than that achieved in experiments using two of these antagonists. 6. Electrically-evoked vasomotor activity is blocked to a larger extent by tissue incubation with 2.5 microM chloroethylclonidine and 30 microM suramin rather than with 10 nM 5 methyl urapidil and 30 microM suramin. As a result, the alpha1-adrenoceptor involved in the vasomotor activity has tentatively been associated with the alpha1B adrenoceptor family subtype. 7. Results support the physiological role of ATP in sympathetic neurotransmission. The present results are consistent with the working hypothesis that human sympathetic vasomotor reflexes involve the coordinated motor action of ATP, NPY, and NA acting on vascular smooth muscle cells. The present results support the concept of sympathetic co-transmission in the human saphenous vein.
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Adenosina Trifosfato/fisiología , Neuropéptido Y/fisiología , Neurotransmisores/fisiología , Norepinefrina/fisiología , Vena Safena/fisiología , Sistema Vasomotor/fisiología , Antagonistas Adrenérgicos alfa/farmacología , Ansiolíticos/farmacología , Arginina/análogos & derivados , Arginina/farmacología , Vasos Sanguíneos/efectos de los fármacos , Vasos Sanguíneos/fisiología , Humanos , Neurotransmisores/antagonistas & inhibidores , Prazosina/farmacología , Antagonistas Purinérgicos , Receptores de Neuropéptido Y/antagonistas & inhibidores , Receptores de Neuropéptido Y/fisiología , Receptores Purinérgicos/fisiología , Vena Safena/efectos de los fármacos , Suramina/farmacología , Sistema Nervioso Simpático/efectos de los fármacos , Sistema Nervioso Simpático/fisiología , Sistema Vasomotor/efectos de los fármacosRESUMEN
BACKGROUND: Surgical repair is the procedure of choice for mitral insufficiency since it preserves better left ventricular structure and function. AIM: To assess the long term clinical and echocardiographic results of mitral valve reconstructive surgery. MATERIAL AND METHODS: A review of clinical and echocardiographic data of 68 patients (34 male, age range 17 to 82 years), subjected to surgical mitral valve repair between December 1991 and March 1998. Preoperative functional capacity of these patients was 2.96 +/- 0.7. Surgical repair was assessed using transesophagic echocardiography in all subjects. RESULTS: The etiology of mitral insufficiency was degenerative in 43 patients, rheumatic in 10, infectious in 6, ischemic in 5 and miscellaneous in 4. The most frequent pathological findings were dilatation of the mitral ring in 42% of patients, chordae tendinae rupture in 32% and enlargement in 24%. A mitral anuloplasty was done in 90% of patients, a cuadrilateral resection of posterior leaflet in 52% and chordae tendinae transference in 12%. An additional surgical procedure was done in 34% of subjects. Three patients died during hospitalization (4.4%). During the follow up of 36.5 +/- 22.3 months, five patients died and one required a mitral valve replacement. The actuarial survival probability was 95.3 +/- 2.6% at one year and 83.5 +/- 6.5% at five years. The reoperation free survival was 100% at one year and 97.4 +/- 2.5% at five years. At the end of follow up the functional capacity improved to 1.25 +/- 0.4. Echocardiography showed absence of mitral insufficiency in 48.4% of patients, minimal, mild and moderate insufficiency in 35.5, 14.5 and 1.6% of patients respectively. CONCLUSIONS: Surgical valve reconstruction in mitral insufficiency has satisfactory long term results and should be the procedure of choice for eligible patients.
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Insuficiencia de la Válvula Mitral/cirugía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Mortalidad Hospitalaria , Humanos , Masculino , Persona de Mediana Edad , Insuficiencia de la Válvula Mitral/mortalidad , Reoperación , Análisis de Supervivencia , Factores de Tiempo , Resultado del TratamientoRESUMEN
BACKGROUND: Since the first surgical coronary revascularization done in Chile in 1971, 5000 such procedures have been performed. AIM: To assess the long term results of coronary revascularization surgery in our institution and to identify prognostic factors. PATIENTS AND METHODS: Five groups of 100 patients each, composed by the first consecutive patients subjected exclusively to coronary bypass surgery in the years 1975, 1980, 1985, 1990 and 1995 were retrospectively studied. RESULTS: Mean age of patients increased from a median of 52 years old in 1975 to 62 years old in 1995. No changes in the frequency of diabetes, hypertension, high serum cholesterol or previous myocardial infarction were observed. There was an increase in the proportion of patients with a recent (< 30 days) infarction that were operated along time. Seventy percent of patients had triple vessel disease or LMT and this proportion did not change. The number of grafts per patients increased form 1.9 to 3.4 and the use of arterial conduits from 0.18 to 0.81. Perioperative mortality remained constant and was 1.6%. Follow up information was obtained for 93% of 492 survivors. Actuarial survival at 5, 10, 15 and 20 years was 93 +/- 1, 82 +/- 2, 62 +/- 3 and 41 +/- 4% respectively. Ninety eight +/- 0.7, 89 +/- 2, 73 +/- 4 and 65 +/- 5% of patients remained free of a new myocardial infarction in the same lapses, respectively. Ninety seven +/- 1, 94 +/- 2, 76 +/- 4 and 47 +/- 7% of patients remained free of a new operation. Stepwise logistical regression analysis identified as bad prognostic factors, in decreasing order: cardiac failure, diabetes, smoking, hypercholesterolemia and age at the moment of operation. CONCLUSIONS: Coronary artery bypass surgery provides good and long lasting clinical improvement. The prognosis of patients is influenced by the presence of cardiac failure, some well known coronary risk factors and age at the moment of operation.
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Puente de Arteria Coronaria , Enfermedad Coronaria/cirugía , Anciano , Anciano de 80 o más Años , Chile , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
UNLABELLED: We prospectively studied the effects of renal protection intervention in 17 patients with preoperative abnormal renal function (plasma creatinine > 1.5 mg/dL) scheduled for elective coronary surgery. Patients were randomized to either dopamine 2.0 micrograms.kg-1.min-1 (Group 1, n = 10) or perfusion pressure > 70 mm Hg during cardiopulmonary bypass (CPB) (Group 2, n = 7). Glomerular filtration rate and effective renal plasma flow were measured with inulin and 125I-hippuran clearances before the induction of anesthesia, after sternotomy and before CPB, during hypo- and normothermic CPB, after sternal closure, and 1 h postoperatively. Plasma and urine electrolytes were measured, and free water, osmolar, and creatinine clearances, as well as fractional excretion of sodium and potassium, were calculated before and after surgery. Significant differences between groups were found before CPB for glomerular filtration rate (higher in Group 1), urine output (2.0 vs 0.29 mL/min in Group 1 versus Group 2), urinary creatinine (66 vs 175 mg/dL), urinary osmolarity (370 vs 627 mOsm/L), osmolar clearance (2.1 vs 0.7 mL/min), and urinary potassium (33 vs 71 mEq/L). There were no differences between groups during hypo- and normothermic CPB. After CPB, the only difference was a slightly higher urinary creatinine in Group 2. Renal plasma flow was lower than normal in all patients before the induction of anesthesia. A nonsignificant trend toward increased flow was seen during hypothermic CPB. Filtration fraction was high before CPB, which suggests efferent arteriolar vasoconstriction, descending toward normal during and after CPB. The same pattern of changes was present in both groups. In conclusion, there were no clinically relevant differences between the two treatment modalities during and after CPB. However, significant differences were observed before CPB, when dopamine seemed to partially revert renal vasoconstriction. IMPLICATIONS: Two protective interventions were compared in patients undergoing heart surgery to prevent deterioration of renal function; these were dopamine infusion throughout the operation and phenylephrine infusion during cardiopulmonary bypass. We found clinically relevant differences only during surgery before cardiopulmonary bypass.
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Puente Cardiopulmonar , Dopamina/farmacología , Riñón/fisiopatología , Fenilefrina/farmacología , Insuficiencia Renal/fisiopatología , Anciano , Anciano de 80 o más Años , Presión Sanguínea/efectos de los fármacos , Femenino , Humanos , Riñón/efectos de los fármacos , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
BACKGROUND: Coronary bypass grafts made with internal mammary artery have better long-term results than those made with saphenous vein. It is possible that the use of both mammary arteries would lead to even better results. AIM: To compare the long-term survival and the incidence of new coronary events of patients, in whom one or two mammary arteries were used as coronary bypass grafts. PATIENTS AND METHODS: One hundred and eight randomly selected patients who received one mammary artery for myocardial revascularization and 108 patients, matched for prognostic factors, who received two mammary arteries were studied. These patients were followed for a mean of 4 years (range 1 to 12 years). Operative complications, hospital mortality and long-term probability of being free of disease were compared in both groups. RESULTS: Operative mortality was similar in both groups (0.9%). Patients that received two mammary arteries had a higher frequency of operative wound complications. Long-term survival was 84% in patients who received one and 83% in patients who received two mammary arteries. The probabilities of being free of myocardial infarction (92 and 82% respectively) and angina (94 and 86% respectively) were lower in the later group. CONCLUSIONS: Patients who received two mammary arteries had a higher probability of a long term disease free survival than patients who received one mammary artery.