ABSTRACT
Background: When the ascending aorta and the femoral artery cannot be used for extracorporeal circulation, an emerging alternative is the use of axillary artery. Aim: To report the experience using the axillary artery for extracorporeal circulation. Patients and methods: Between November 1998 and May 2002, 22 patients (14 male) were operated with extracorporeal circulation, cannulating the axillary artery. Briefly, an incision is made below the middle third of the clavicle and a cut is made on major pectoris muscle. Minor pectoris muscle is retracted and axillary artery is exposed. It is cannulated directly or with the aid of a prosthesis. Results: Right axillary artery was used in 21 patients and in 20 it was cannulated with the aid of a prosthesis. Mean flow was 4.5 + 0.6 l/min. The most common indications were aortic dissection or aneurysms. The most common procedures done, were ascending aorta replacement in 8 cases and replacement of ascending aorta and aortic arch in 5. Thirty five percent of operations were emergencies and 32 percent were reoperations. In 15 patients (68 percent), a circulatory arrest was done. Of these, retrograde brain perfusion was used in 9, antegrade brain perfusion through the same axillary artery was used in 2 and mixed perfusion was used in 2. One patient had a complication related to the axillary cannulation. None had cerebrovascular accidents or thromboembolic complications. Two patients died in the postoperative period. Patients were followed up to 42 months after the procedure and no secondary complications of the cannulation were detected. Conclusions: When the ascending aorta and the femoral artery cannot be used, axillary artery is a good alternative for extracorporeal circulation
Subject(s)
Humans , Male , Adult , Female , Middle Aged , Axillary Artery , Extracorporeal Circulation/methods , Catheterization , Cardiovascular Diseases , Aortic Aneurysm/surgery , Aortic Coarctation/surgeryABSTRACT
Background: During the last five years, 65 patients with univentricular heart have been treated surgically in our institution, according to a protocol of staged operations that have been previously reported. Aim: To evaluate the early and mid-term outcome of those patients that have completed their staging protocol by means of a Fontan procedure. Patients and Methods: Between April 1996 and June 2001, 23 patients (age 16 to 223 months) underwent a Fontan procedure, 15 with an intracardiac lateral tunnel technique and 8 with an extracardiac conduit. A retrospective review of their clinical, surgical, echocardiographic, angiographic and hemodynamic data was performed, trying to identify risk factors for both mortality and functional capacity (FC). Follow up was complete in all survivors. Results: Three patients died early after surgery (13.04 percent). Excessive pulmonary blood flow was a risk factor for early death (p= 0.03). One patient died at 14 months. Follow up was 29.9 months (1-63). For those who survived the operation, five years survival was 93.3 percent. The majority of patients are in FC I or II, with no related risk factors. Conclusions: Our current results are comparable with those of larger series. Patients reach good FC and mid-term survival, irrespective of type of single ventricle or the surgical strategy
Subject(s)
Humans , Male , Child, Preschool , Female , Infant , Fontan Procedure , Heart Diseases , Heart Bypass, Right/statistics & numerical data , Postoperative Period , Disease-Free Survival , Heart Septal Defects, Ventricular , Ventricular Dysfunction/surgery , HemodynamicsABSTRACT
Antecendentes: La cirugía es el tratamiento de elección de la coartación aórtica. Sus resultados deben evaluarse no sólo en base de morbimortalidad operatoria si no también en relación a la incidencia de coartación residual y recoartación, hecho que es más frecuente en recién nacidos. Actualmente, dado el interés progresivo en la angioplastia primaria como tratamiento de esta patología se hace necesario conocer los resultados actuales del tratamiento quirúrgico. Objetivo: Analizar y reportar nuestra experiencia en el subgrupo de pacientes de mayor riesgo. Método: Se analizaron retrospectivamente todos los pacientes de hasta 3 meses de edad (menores de 120 días) sometidos a cirugía de coartación aórtica en nuestra institución, entre enero de 1989 y agosto de 1999. Se efectuó un análisis descriptivo de las características generales y de la técnica quirúrgica, así como de los resultados inmediatos y alejados. Resultados: Cincuenta y nueve pacientes fueron sometidos a reparación quirúrgica de la coartación aótica. La edad fue de 35ñ33 días, correspondiendo un 57 por ciento a recién nacidos. Treinta y seis pacientes (61 por ciento) eran del sexo masculino. El peso fue de 3.650ñ1.057 g. La coartación aótica se presentó en forma aislada en 28 pacientes (47,5 por ciento), asociada a CIV en 7 (11,9 por ciento) y a otra patología intracardíaca en 24 (40,7 por ciento). Treinta y seis pacientes (61 por ciento) presentaron unarco aórtico normal, 17 hipoplasia del istmo (28,8 por ciento) y 6 hipoplasia del arco transverso (10 por ciento). La principal indicación de cirugía fue insuficiencia cardíaca. Al momento de la cirugía 17 pacientes (31,5 por ciento) se encontraban en ventilación mecánica y 20 (37 por ciento) habían recibido de protaglandinas. La técnica quirúrgica fue: anastomosis término-terminal en 31 (52,5 por ciento); anastomosis término-terminal extendida en 24 (40,7 por ciento) y colgajo subclavio en 4 (6,7 por ciento). El tiempo de clampeo aórtico fue de tomosis fue de 18,4ñ6,2 minutos. En siete pacientes (11.9 por ciento) se efectuó cirugía cardíaca adicional. Cuatro pacientes (6,7 por ciento) presentaron coartación aórtica residual la cual motivó cirugía en un caso (1,7 por ciento) y angioplastia en otro. Ningún paciente presentó paraplejia. La mortalidad quirúrgica a 30 días fue de 3,4 por ciento (2 casos). Siete pacientes (11,8 por ciento) fallecieron durante el seguimiento, obteniéndose una sobrevida actuarial a 5 años de 83,9 por ciento
Subject(s)
Humans , Male , Infant, Newborn , Infant , Female , Angioplasty , Aortic Coarctation/surgery , Age Distribution , Anastomosis, Surgical/methods , Birth Weight , Aortic Coarctation/mortality , Heart Failure/surgery , Reoperation , Retrospective StudiesABSTRACT
Background: The implantation of pacemakers improves cardiac function and quality of life, in particular with dual chamber DDD and DDDR modes. Aim: To evaluate our clinical experience and results on pacemaker implantation, from 1963 to 1998. Material and methods: Computerized data collected from 2,445 consecutive paced patients was reviewed. A total of 3,554 operative procedures were performed, including 412 procedures for complications and 697 pacemaker replacement. Patient survival was determined from clinical records, inquiry to pacemaker manufacturers and death certificates from Servicio de Registro Civil e Identificaci-n de Chile (Chilean Civil and Identification Registry). Results: Use of dual chamber (DDD and DDDR) pacemakers increased progressively up to 74 percent from 1988 to 1998. Complication rate was 42 percent in the 1963-1976 study period, it decreased to 10.6 percent in the 1977-1987 study period, and to 5.6 percent by 1988-1998. Only two patients died during surgery in the study period (0.08 percent). In the 1977-1987 period, pacemakers lasted 10.6 years. Survival rates were 52 percent at ten years, 33 percent at 15 years, and 21 percent at 20 years, with a median survival of 11.7 years, and 7.24 years in patients over 80 years old. Conclusions: Transvenous permanent pacing can be accomplished today with a low complication rate, mainly due to better technology and surgical procedures
Subject(s)
Humans , Male , Female , Pacemaker, Artificial , Cardiovascular Diseases , Sick Sinus SyndromeABSTRACT
Background. Ischemic mitral regurgitation (IMR) is a severe condition which may be best treated by surgery, nowithstanding a relatively high mortality rate. Objectives. To evaluate the results of mitral valve replacement or repair in patients with IMR. Patients and methods. Retrospective review of the clinical records in 29 patients with IMR who were surgically treated from 1990 to 1999. They represent 8 percent of surgical procedures on the mitral valve. Results. Mean age was 67 ñ 9 years. Surgery was performed urgently in 19 patients (66,5 percent). NYHA functional class was 3.4 ñ 0.8. The mechanism of IMR was annular dilatation and spreading of papillary muscles in 18 patients, papillary muscle rupture in 9 and fibrosis in 2. Mitral valve replacement was performed in 14 patients and mitral valve repair in 15. Twenty four patients (83 percent) had concomitant myocardial revascularization. Overall surgical mortality was 24 percent; 26 percent for mitral replacement and 13 percent for mitral valve repair (p=0.215). On follow up of 26ñ33 months, one year survival was 76ñ0.8 percent and 5 years survival was 59ñ12 percent. Excluding in hospital mortality, survival was 100 percent at one year and 78ñ14 percent at 5 years. Functional class improved in all survivors, to 1.4ñ0.5. Late echocardiographic evaluation of patients with mitral valve repair showed absence of mitral regurgitation in 58 percent, 1+ MR in 17 percent and 2+ MR in 25 percent. Conclusion. In spite of a high perioperative mortality, surgery for IMR is a valuable procedure for patients with an otherwise highly lethal disease
Subject(s)
Humans , Male , Female , Middle Aged , Heart Valve Prosthesis Implantation , Mitral Valve Insufficiency/surgery , Postoperative Complications , Disease-Free Survival , Intraoperative Complications , Myocardial RevascularizationABSTRACT
In 1991, a technique to exclude aortic aneurysms from circulation inserting an endoluminal graft through the femoral artery, was described. This procedure, usually used for elective abdominal aneurysms, can also be used in the thoracic aorta. We report a 41 years old male with a Marfan syndrome, presenting with a descending aorta aneurysm that ruptured to the mediastinum and pleural cavity. He was compensated hemodynamically and an endovascular stent-graft was deployed at the ruptured zone, through the femoral artery. The postoperative evolution of the patient was uneventful. This technique will allow a less invasive treatment of ruptured aortic aneurysms
Subject(s)
Humans , Male , Aneurysm, Ruptured , Aortic Aneurysm, Thoracic/surgery , Blood Vessel Prosthesis , Marfan Syndrome/complicationsABSTRACT
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 per cent) were male and 12 (5.6 per cent) female. The mean interval between the operations was 125.7 months (range 6-252 months). 10 (4,6 per cent) were emergency surgeries. Overall operative mortality was 5.6 per cent (11 deaths) and in 5 patients (3.4 per cent) 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 per cent, a 10 years survival rate of 73.1 per cent and a 15 years survival rate of 53.4 per cent. 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
Subject(s)
Humans , Male , Adult , Female , Middle Aged , Coronary Artery Bypass , Reoperation/statistics & numerical data , Postoperative Complications , Retrospective Studies , Survivors , Disease-Free Survival , Intraoperative ComplicationsSubject(s)
Humans , Male , Adolescent , Adult , Female , Middle Aged , Heart Block/therapy , Pacemaker, Artificial , Sick Sinus Syndrome , Clinical Evolution , Disease-Free Survival , Electrodes, Implanted , Pacemaker, Artificial , ReplantationABSTRACT
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
Subject(s)
Humans , Male , Middle Aged , Aorta/microbiology , Prosthesis-Related Infections/therapy , Heart Valve Prosthesis/microbiology , Graft Survival/immunology , Mediastinitis/microbiology , Obesity/complications , Surgical Flaps , Systemic Inflammatory Response Syndrome/therapyABSTRACT
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 19ñ4.5 percent, mean systolic pulmonary artery pressure 48ñ13 mmHg (24-70) and mean pulmonary vascular resistance 2.6 Wood Units (1-5). Fourteen patients (58 percent) had a previous median sternotomy. Immunosupression did not include induction therapy and steroids were discontinued early...
Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Heart Failure/surgery , Heart Transplantation/methods , Tissue Survival , Prospective Studies , Graft Rejection , Graft Survival , Immunosuppressive Agents/therapeutic use , Hemodynamics , Hypertension/complications , Heart Failure/complicationsABSTRACT
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 characterisation 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 1percent 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
Subject(s)
Humans , Neuropeptide Y , Sympathetic Nervous System/physiology , Synaptic Transmission/physiology , Saphenous Vein/pathology , Saphenous Vein , Biopsy , Biogenic Monoamines/pharmacology , Norepinephrine/pharmacology , Transcutaneous Electric Nerve StimulationABSTRACT
Antecedentes: realizamos un estudio prospectivo de 236 pacientes sometidos a implante de marcapaso DDD bicameral. Los parámetros nominales de implante permiten márgenes de seguridad de estimulación más que suficientes. Las mejoras en la tecnología de marcapasos y electrodos han permitido reducir los umbrales de captura y, por lo tanto, la programación de los parámetros de salida. Dichos cambios pueden significar una reducción en el consumo de la batería a largo plazo, produciendo una mayor durabilidad del generador. Métodos y resultados: se estudió 236 pacientes consecutivos implantados con marcapasos Pacesetter DDD para determinar el impacto de la reprogramación en la durabilidad y costo del implante del marcapaso. Se excluyó a 36 pacientes, 19 murieron, 13 no tuvieron suficientes controles y 4 fueron reprogramados a modo VVI. Los 200 pacientes restantes completaron al menos 18 meses de seguimiento y se les implantó generadores capaces de medir umbrales de estimulación crónico, ancho de pulso, impedancia y energía de la batería. Comparamos la durabilidad estimada basada en la energía de la batería bajo parámetros de implante nominales, con aquella basada en los parámetros obtenidos tras la reprogramación durante el seguimiento. La estimación de durabilidad fue de 6,89 años bajo parámetros nominales y de 10,5 años bajo parámetros de programación final (p<0,001). Conclusiones: la reprogramación podría aumentar la durabilidad y reducir el costo de implante de los marcapasos. En nuestro estudio la reprogramación aumentó la durabilidad del marcapaso en 3,6 años y ocasionó una reducción promedio en sus costos de 330 dólares por año
Subject(s)
Humans , Health Care Costs , Pacemaker, Artificial/economics , Cost-Benefit Analysis , Electrodes, Implanted/economics , Prospective StudiesABSTRACT
En este estudio caracterizamos la liberación de NPY de biopsias de la arteria y vena mamaria. Se induce la liberación de los neurotransmisores por medio de despolarización eléctrica de los nervios simpáticos perivasculares. Con estímulo de 70 V, 0,5 msec, 40 Hz por 5 min, segmentos de la arteria mamaria liberan 17,7 ñ 6,7 fmol (n=4) de NPY, la vena libera 4,3 ñ 1,5 fmol (n=4), valores que corresponden a un 1-2 por ciento del NPY en la biopsia. El NPY liberado por estímulo eléctrico no es metabolizado en la sinapsis neuroefectora. La liberación del NPY al medio de superfusión tiene un curso temporal lento, la máxima liberación ocurre a los 10 min del estímulo. La liberación del NPY es dependiente de la duración del estímulo (coeficiente de correlación = 0,647, p<0,01); y de la frecuencia de estimulación (coeficiente de correlación = 0,611, p<0,05), indicando que la liberación es un proceso controlado por la frecuencia de la descarga y por la intensidad del estímulo simpático vasomotor. El proceso de liberación es dependiente del calcio, ya que en ausencia de calcio extremo, la liberación de NPY se reduce en 78 por ciento. El NPY actúa sobre receptores postsinápticos, donde produce un efecto facilitador significativo de la acción vasomotora de NA y ATP. En conclusión, NPY se libera al espacio sináptico por exocitosis, donde participa junto a NA y ATP en la regulación del tono vasomotor simpático
Subject(s)
Humans , In Vitro Techniques , Mammary Arteries/pathology , Neuropeptide Y , Chromatography , Exocytosis , Immunoenzyme Techniques , Presynaptic Terminals/physiologyABSTRACT
Objetivos: el uso de una miniesternotomía para la reparación de ciertas cardiopatías congénitas tendría beneficios cosméticos, menor dolor postoperatorio y una hospitalización más breve, sin sacrificar los resultados de la intervención. Nuestro objetivo es describir la técnica quirúrgica y presentar los resultados de una serie inicial de pacientes. Material y método: desde enero de 1998 adoptamos la técnica de miniesternotomía para el cierre de comunicación interauricular (CIA) en pacientes pediátricos. Desde entonces, hasta diciembre de 1998 se intervinieron 16 pacientes (mujeres: 8; hombres: 8), de entre 9 meses a 13 años de edad (x:3,5 años), con peso de entre 8 a 36 kg (x:15,4 kg). Trece pacientes presentaban una CIA tipo ostium secundum, 2 una CIA tipo ostium primum con cleft de la válvula mitral y 1 paciente una CIA tipo seno venoso-cava inferior. Se describe la técnica quirúrgica. Resultados: en 8 pacientes se realizó cierre directo del defecto y en 8 se empleó parche de pericardio; en 2 se cerró un cleft mitral. En ningún paciente fue necesario ampliar la estemotomía. El tiempo de circulación extracorpórea fluctuó entre 20 a 76 minutos (x:49,5) y el clampeo aórtico entre 7 a 53 minutos (x:20,5). El ecocardiograma pre-alta no demostró defectos residuales en ningún paciente. La estadía hospitalaria postoperatoria fue entre 3 y 4 días y el dolor fue subjetivamente menor. No hubo morbilidad ni mortalidad. Comentario: la miniesternotomía permite un adecuado y seguro acceso para la reparación de CIA en pacientes pediátricos, con buenos resultados cosméticos, corta estadía hospitalaria y aparentemente menos dolor. Esta técnica tendría ventajas sobre el uso de toracotomía anterior derecha y puede utilizarse para reparar otros defectos, como comunicación interventricular y canal auriculoventricular completo
Subject(s)
Humans , Male , Female , Sternum/surgery , Heart Septal Defects, Ventricular/surgery , Catheterization , Length of Stay , Cardiovascular Surgical Procedures/instrumentation , Cardiovascular Surgical Procedures/methods , Minimally Invasive Surgical Procedures/methodsABSTRACT
Antecedentes: desde mediados de la presente década se han propuesto distintos accesos mínimamente invasivos en cirugía cardiovascular, entre ellos la miniesternotomía. Objetivo: presentar nuestra experiencia inicial en cirugía valvular a través de miniesternotomía. Pacientes: entre octubre 1997 y diciembre 1998, se efectuó un reemplazo valvular aórtica y en otra un reemplazo valvular mitral, a través de una miniesternotomía media en "J". Nueve pacientes eran hombres. El promedio de edad fue de 53,6 años (29-73). Todos los pacientes fueron operados con monitorización ecocardiográfica transesofágica. Técnica quirúrgica. Se efectuó una esternotomía media en "J" en el 3º o 4º espacio intercostal derecho con una incisión cutánea menor a 10 cm en todos los casos. Para el retorno arterial se canuló la aorta ascendente y para el drenaje venoso, la orejuela derecha con una cánula única. La protección miocárdica se efectuó con cardioplegia cristaloide infundida en forma anterógrada y/o retrógrada a 4ºC. El drenaje de las cavidades izquierdas se efectuó con un catéter introducido a través de la vena pulmonar superior derecha. Los reemlazos valvulares aórticos se efectuaron a través de una aortotomía oblicua y el reemplazo valvular mitral a través de una auriculotomía izquierda superior...
Subject(s)
Humans , Male , Female , Adult , Middle Aged , Thoracic SurgeryABSTRACT
Background: Since the first surgical coronary revascularization done in Chile in 1971, 5000 such procedures bave 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 yean old in 1995. No changes in the frequency of diabetes, hypertension, high serum cholesterol or prvious mycardial 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 percent. Follow up information was obtained for 93 percent of 492 survivors. Actuarial survival at 5, 10, 15 and 20 years was 93ñ1, 82ñ2, 62ñ3 and 41ñ4 percent respectively. Ninety eight ñO.7, 89ñ2, 73ñ4 and 65ñ5 percent of patients remained free of a new myocardial infarction in the same lapses, respectively. Ninety seven ñl, 94ñ2, 76ñ4 and 47ñ7 percent 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
Subject(s)
Humans , Male , Female , Middle Aged , Coronary Disease/surgery , Thoracic Surgery/trends , Cardiac Surgical Procedures/trends , Postoperative Complications , Smoking , Coronary Artery Bypass/statistics & numerical data , Retrospective Studies , Risk Factors , Survivors/statistics & numerical data , Diabetes Mellitus , Intraoperative Complications , Angina Pectoris , Myocardial Infarction , Age Distribution , Sex Distribution , Hypertension/epidemiology , Prognosis , Myocardial Revascularization/statistics & numerical dataABSTRACT
El cálculo habitual de resistencia vascular sistémica (SVR) asume que la circulación se comporta como una resistencia, o sea, que relaciona en forma lineal los valores de presión y flujo medios. Por analogía con la ley de Ohm se utiliza la ecuación SVR=(PAM-PVC)/DC, es decir, la caída de presión entre los territorios arterial y venoso dividida por el débito cardíaco. Esta ecuación es usada universalmente en clínica y en investigaciones fisiológicas, aunque debiera ser obvio que es una sobre símplícación. La definición matemática de resistencia es la pendiente de la función presión/flujo, la que resulta difícil de determinar en pacientes. Para establecer si la ecuación SVR=(PAM-PVC)/DC es apropiada, determinamos experimentalmente la relación presión/flujo en 30 pacientes bajo circulación extracorpórea. La relación encontrada no correspondió a la ecuación arríba citada, ya que la presión a flujo cero (P0) resultó en todos los pacientes significativamente mayor que PVC. La pendiente de la relación presíón/flujo determinada experimentalmente, o sea la resistencia propiamente tal corresponde en realidad a la ecuación R=(PAM P0)/DC. Usando esta fórmula se obtienen valores de resistencia menores que usando la ecuación habitual, y no se confirma que la resistencia sea inversamente proporcional al débito cardíaco, como ha sido publicado
Subject(s)
Humans , Male , Female , Adult , Middle Aged , Vascular Resistance/physiology , Blood Pressure Determination , Extracorporeal Circulation/methods , Hemodynamics , Myocardial Revascularization/methodsABSTRACT
Se estudiaron prospectivamente 17 pacientes con función renal preoperatoría alterada (creatininemia plasmática> 1,5 mg/dl) sometidos a cirugía con circulación extracorpórea. Los pacientes fueron randomizados a dos esquemas de protección renal. Grupo 1: Dopamina 2 ug/kg/min y grupo 2: Presión de perfusión elevada (70 mm Hg) durante circulación extracorpórea. Se midió filtración glomerular y flujo plasmático renal efectívo como clearances de inulina e 1251-hippuran, antes de la anestesia, durante la disección de la arteria mamaría, en circulación extracorpórea (hipotermia y normotermia), cierre del esternón y una hora del postoperatorío. Se midió además díuresís, electrolitos en sangre y orina, y clearances de creatinina, osmolar y de agua libre. La filtración glomerular durante la cirugía, antes de circulación extracorpórea, fue signifícativamente mayor en el grupo dopamina. Hubo tendencia a la disminución de la filtración glomerular durante la fase de hipotermia en ambos grupos. Por otra parte, el flujo plasmático renal efectivo aumentó discretamente respecto del control durante hipotermia en ambos grupos. Se encontró diferencias significativas entre ambos grupos durante cirugía, antes de circulación extracorpórea, en volumen urinario G1 (2,00 ñ 1,67 mL/min) vs G2 (0,29 ñ 0,19 mL/min), osmolaridad urinaria G1 (370 ñ 11 mL/min) vs G2 (627 ñ 157 mL/min), clearance osmolar G1 (2,15 ñ 1,42 mL/min) vs G2 (0,68 ñ 0,37 mL/mín), y potasio urinario G1 (33,1 ñ 12 mEq/L) vs G2 (71,1 ñ 23,7 mEq/L). Estos hallazgos sugieren un efecto de la dopamina sobre factores prerrenales en estos pacientes, ya que en los pacientes que no recibieron dopamina los valores encontrados son sugerentes de vasoconstricción renal
Subject(s)
Humans , Male , Female , Middle Aged , Dopamine/pharmacology , Renal Insufficiency/drug therapy , Extracorporeal Circulation/methods , Creatinine/blood , Creatinine/urine , Glomerular Filtration Rate , Osmolar Concentration , Prospective Studies , Renal Insufficiency/surgery , Myocardial Revascularization/methodsSubject(s)
Humans , Female , Aged , Heart Neoplasms , Sarcoma , Echocardiography , Heart Neoplasms/epidemiologyABSTRACT
Sepsis from an infected cardiac value can lead to bacterial seeding and destruction of the arterial wall with formation of a mycotic aneurysm. The natural history of these lesions is the rupture. We report the case of a 20 year old female who was admitted to our institution with massive mitral regugirtation and emboli of the central nervous system and both lower extremities. She underwent emergency valve replacement and then, staged treatment of her ischmic legs and multiple asymptomatic mycotic aneurysms. Superior mesenteric, right common iliac and left superficial femoral arteries. A splenectomy was required to treat a splenic abscess. An aneurysm of a peripheral branch of the middle cerebral artery was medically treated, demonstrating reduction in size on subsequente angiogram.She recoverd uneventfully and remains asymptomatic after 20 months of follow up. The development of new diagnostic and therapeutic tools had led to a decrease ot these complications during infectious endocarditis. However, in the patient with late diagnosis and symptoms in different territories, the mycotic aneurysm must be kept in mind to provide the patient with appropriate treatment