RESUMEN
In a randomised trial, we compared the effects of oral sildenafil (0.5 mg.kg(-1) ) and placebo, administered the day before cardiac surgery, in 24 children. In sildenafil vs placebo patients, pre-cardiopulmonary bypass median (IQR [range]) cyclic-guanosine-monophosphate was not significantly different (29.9 (2.1-208.1 [0.5-391.5]) vs 5.2 (0.3-54.6 [0-628.9]) pmol.ml(-1) , respectively). Post-cardiopulmonary bypass, nitrate/nitrite levels were also not significantly different (0.7 (0-8.0 [0-142.8]) vs 0 (0-2.7 [0-52.7]) µM, respectively). Postoperatively, mean (SD) pulmonary vascular resistance (2.64 (2.28) vs 1.90 (1.12) WU.m(-2) , respectively and oxygenation index (5.29 (4.60) vs 3.38 (2.54), respectively) remained unchanged, whilst oxygen delivery (57.18 (21.24) vs 74.13 (35.46) ml.min(-1) .m(-2) , respectively) and bi-ventricular systolic function (left ventricle 3.78 (0.94) vs 4.55 (1.08) cm.s(-1) , respectively; p=0.002; right ventricle 6.93 (1.47) vs 8.09 (2.25) cm.s(-1) , respectively; p<0.001) were significantly reduced in the sildenafil group. In this trial, pre-operative sildenafil did not affect postoperative pulmonary vascular resistance. There was, however, a negative impact on ventricular function and oxygenation.
Asunto(s)
Puente Cardiopulmonar/efectos adversos , Defectos de los Tabiques Cardíacos/cirugía , Hipertensión Pulmonar/prevención & control , Piperazinas/uso terapéutico , Sulfonas/uso terapéutico , Vasodilatadores/uso terapéutico , Administración Oral , Preescolar , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/fisiopatología , Femenino , Humanos , Hipertensión Pulmonar/etiología , Hipertensión Pulmonar/fisiopatología , Lactante , Masculino , Terapia por Inhalación de Oxígeno , Piperazinas/administración & dosificación , Cuidados Posoperatorios/métodos , Cuidados Preoperatorios/métodos , Arteria Pulmonar/efectos de los fármacos , Arteria Pulmonar/fisiopatología , Purinas/administración & dosificación , Purinas/uso terapéutico , Citrato de Sildenafil , Sulfonas/administración & dosificación , Resistencia Vascular/efectos de los fármacos , Vasodilatadores/administración & dosificación , Función Ventricular Izquierda/efectos de los fármacos , Función Ventricular Derecha/efectos de los fármacosRESUMEN
BACKGROUND: Right heart failure after cardiopulmonary bypass can result in severe hemodynamic compromise with high mortality, but the underlying mechanisms remain poorly understood. After ischemia-induced right ventricular failure, alterations in the interventricular septal position decrease left ventricular compliance and limit filling but may also distort left ventricular geometry and compromise contractility and relaxation. This study investigated the effect of acute isolated right ventricular ischemia on biventricular performance and interaction and the response of subsequent right ventricular unloading by use of a modified Glenn shunt. METHODS: In 8 pigs isolated right ventricular ischemic failure was induced by means of selective coronary ligation. A modified Glenn circuit was then established by a superior vena cava-pulmonary artery connection. Ventricular performance was determined by conductance catheter-derived right ventricular pressure-volume loops and left ventricular pressure-segment length loops. Hemodynamic data at baseline, after right ventricular ischemia, and after institution of the Glenn circuit were obtained during inflow occlusion, and the load-independent contractile indices were derived. RESULTS: Right ventricular free-wall ischemia resulted in acute right ventricular dilation (118 +/- 81 mL vs 169 +/- 70 mL, P =.0008) and impairment of left ventricular contractility indicated by the reduced end-systolic pressure-volume relation slope (50.0 +/- 19 mm Hg/mm vs 18.9 +/- 8 mm Hg/mm, P =.002) and preload recruitable stroke work index slope (69.6 +/- 26 erg x cm(-3) x 10(3) vs 39.7 +/- 13 erg x cm(-3) x 10(3), P =.003). In addition, left ventricular relaxation (tau) was significantly prolonged (33.3 +/- 10 ms vs 53.0 +/- 16 ms, P =.012). Right ventricular unloading with the Glenn shunt reduced right ventricular dilation and significantly improved left ventricular contraction, end-systolic pressure-volume relation slope (18.9 +/- 8 mm Hg/mm vs 35.8 +/- 18 mm Hg/mm, P =.002), preload recruitable stroke work index slope (39.7 +/- 26 erg x cm(-3) x 10(3) vs 63.0 +/- 22 erg x cm(-3) x 10(3), P =.003), and diastolic performance (tau 53.0 +/- 16 ms vs 43.5 +/- 13 ms, P =.001). CONCLUSIONS: Right ventricular ischemia-induced dilation resulted in acute impairment of left ventricular contractility and relaxation. A modified Glenn shunt attenuated the left ventricular dysfunction by limiting right ventricular dilation and restoring left ventricular cavity geometry.
Asunto(s)
Puente Cardíaco Derecho , Disfunción Ventricular Izquierda/cirugía , Disfunción Ventricular Derecha/cirugía , Animales , Diástole , Dilatación Patológica , Modelos Animales de Enfermedad , Femenino , Ventrículos Cardíacos/patología , Hemodinámica , Masculino , Isquemia Miocárdica/complicaciones , Porcinos , Sístole , Disfunción Ventricular Izquierda/etiología , Disfunción Ventricular Derecha/etiologíaRESUMEN
OBJECTIVE: In repair of truncus arteriosus the accepted methods of establishing right ventricle (RV) to pulmonary artery (PA) continuity utilize an allograft or xenograft valved conduit. Alternatively, the PA confluence may be directly anastomosed to the RV with anterior patch augmentation, which may allow growth and delay or avoid subsequent RVOT obstruction. These methods of RVOT reconstruction were evaluated in infants undergoing truncus arteriosus repair. METHODS: A retrospective analysis of 61 infants undergoing repair of truncus arteriosus between November 1988 and June 2000 was performed. Median age was 34 days (range 1 day to 6.4 months). The patient cohort was subdivided into two groups (1) Valved conduit group: RV to PA continuity performed with a conduit in 38 patients using allograft (28) or xenograft (10). (2) Direct anastomosis group: direct RV-PA anastomosis performed in 23 patients, augmented anteriorly with monocusp (15) or simple pericardial patch (eight). RESULTS: There were eight hospital deaths (13%, 95% confidence limits 5--21%). Hospital mortality did not differ significantly between group 1 and 2 (three patients (8%) versus five patients (22%) respectively, P=0.23). By multivariate analysis, low operative weight (P=0.023), severe truncal regurgitation (P=0.022) and major coronary abnormalities (P=0.018), were independent risk factors for hospital death. Hospital survivors were followed-up from 1.3 months to 11.8 years (mean 4.2+/-3.4 years). There were eight late deaths with survival of 73+/-6% at 2 years and beyond. Survival was not influenced by method of RVOT reconstruction (Conduit versus direct RV-PA anastomosis, 2.76+/-7%, 63+/-10%, respectively, P=0.23). Freedom from surgical RVOT reintervention was 56+/-10% in group 1 and 89+/-10% in group 2 at 10 years (P=0.023). The use of a xenograft conduit was an independent risk factor for reintervention (P<0.001). CONCLUSIONS: In truncus arteriosus repair, RV to PA continuity established by a direct anastomosis was associated with a low incidence of surgical RVOT re-intervention. This technique has the potential for RVOT growth and may be a useful alternative when an appropriate allograft is unavailable, particularly in the neonate where the risk of pulmonary hypertension are lower.
Asunto(s)
Tronco Arterial Persistente/cirugía , Obstrucción del Flujo Ventricular Externo/cirugía , Implantación de Prótesis Vascular , Procedimientos Quirúrgicos Cardíacos/métodos , Estudios de Casos y Controles , Femenino , Mortalidad Hospitalaria , Humanos , Lactante , Masculino , Complicaciones Posoperatorias/epidemiología , Reoperación/estadística & datos numéricos , Resultado del TratamientoRESUMEN
BACKGROUND AND AIM OF THE STUDY: By providing a superior hemodynamic profile, the stentless valve design allows ventricular remodeling and may improve patient survival after aortic valve replacement (AVR). Compared with stent-mounted prostheses, implantation is more complex and requires a longer ischemic time; this may adversely affect surgical risk, especially if patients are elderly or require a concomitant procedure. The mid-term clinical and hemodynamic performance of the Toronto SPV bioprosthesis in a predominantly elderly patient group was analyzed. METHODS: A total of 123 patients (median age 72 years) underwent AVR with the Toronto SPV. Concomitant procedures (mainly coronary artery bypass grafting, CABG), were performed in 60 patients (49%). Clinical details were recorded, with 100% follow up (total 317 patient-years). Hemodynamic evaluation, by serial echocardiography, was performed at four and 18 months after implantation. RESULTS: The early mortality rate was low (0.8%). Mean (+/- SD) actuarial survival at 53 months was 78 +/- 5.9%, with most patients (91%) in NYHA classes I and II. Freedom from valve-related complications were: endocarditis 93.8 +/- 2.3%, thromboembolism 90.3 +/- 3.7% and bleeding 95.8 +/- 1.8%; there were no structural failures. The valve hemodynamic profile was excellent for all sizes: peak gradient 8.8 +/- 4.3 mmHg, effective orifice area 1.9 +/- 0.54 cm2 with significant improvement in left ventricular fractional shortening. CONCLUSION: In this patient population the Toronto SPV was a suitable choice. Advanced age, a requirement for concomitant procedures and increased ischemic times did not adversely affect surgical risk. AVR with the Toronto SPV provided an excellent hemodynamic profile, and improved both left ventricular function and NYHA functional class.
Asunto(s)
Bioprótesis , Hemodinámica/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Ecocardiografía , Endocarditis/etiología , Femenino , Estudios de Seguimiento , Implantación de Prótesis de Válvulas Cardíacas , Hemorragia/etiología , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Tromboembolia/etiología , Resultado del TratamientoRESUMEN
BACKGROUND: Transmyocardial laser revascularization (TMR) has been established with the carbon dioxide (CO2) laser. The largely unstudied excimer laser creates channels through chemical bond dissociation instead of thermal ablation, thereby avoiding thermal injury. We sought to compare the effects of CO2 and excimer TMR in a porcine model of chronic ischemia. METHODS: Pigs underwent ameroid constrictor placement on the circumflex artery to create chronic ischemia. TMR was performed with CO2 (n = 8) or excimer (n = 8) laser 6 weeks later; controls (n = 7) had ameroid placement only. Regional myocardial blood flow (RMBF), determined by radioactive microspheres, and regional myocardial function, determined by percent segmental shortening (%SS), were assessed 18 weeks after ameroid placement. RESULTS: Values are mean +/- SD. In the ischemic zone, RMBF (mL/min/g) was improved in the CO2 (0.73 +/- 0.19) and excimer (0.78 +/- 0.22) groups when compared with controls (0.55% +/- 0.12%, p < 0.05). %SS was also improved in the CO2 (15.2% +/- 5.5%) and excimer (15.3% +/- 5.1%) groups when compared with controls (8.0% +/- 4.2%, p < 0.05). CONCLUSIONS: Excimer and CO2 TMR significantly improve RMBF and regional function in this porcine model of chronic myocardial ischemia despite fundamentally different tissue interactions.
Asunto(s)
Circulación Coronaria/fisiología , Enfermedad Coronaria/cirugía , Terapia por Láser/instrumentación , Revascularización Miocárdica/instrumentación , Función Ventricular Izquierda/fisiología , Animales , Enfermedad Coronaria/fisiopatología , Diseño de Equipo , Hemodinámica/fisiología , PorcinosRESUMEN
BACKGROUND: The issue of performing simultaneous pulmonary resection and cardiac surgery in patients with coexisting lung carcinoma and ischaemic heart disease remains controversial. We report our experience and review the literature. METHODS: Thirteen patients (male ten, female three; mean age 65 years) underwent simultaneous cardiac surgery and pulmonary resection. Lung pathology consisted of primary lung carcinoma (n = 10), benign disease (n = 2) and carcinoid (n = 1). Lung resections included pneumonectomy (n = 3), lobectomy (n = 4), segmentectomy (n = 1) and local excision (n = 5). Cardiac procedures consisted of coronary artery bypass grafting (CABG) in 11, aortic valve replacement in one and mitral valve repair with CABG in one patient. In all but one case the lung resection was performed prior to heparinization and cardiopulmonary bypass (CPB). In two patients, with suitable coronary anatomy, myocardial revascularization without CPB was performed to reduce morbidity. RESULTS: There was no hospital mortality. Postoperative blood loss and ventilation requirements were reduced in the patients who were operated on without CPB. Prolonged ventilatory support was required in two cases. All patients with benign pathology are alive. In the lung cancer group there have been five late deaths: disseminated metastatic disease (n = 3), anticoagulant related haemorrhage (n = 1) and broncho-pleural fistula (n = 1). Of the remaining five patients four are alive and disease free 7-23 months post-operatively; one patient has recurrent disease 40 months post-operatively. CONCLUSIONS: Simultaneous pulmonary resection and cardiac surgery is associated with acceptable operative morbidity and mortality. In patients with lung carcinoma long-term survival was determined by tumour stage. The avoidance of CPB may be advantageous by decreasing blood loss and ventilation requirements.
Asunto(s)
Puente de Arteria Coronaria , Neoplasias Pulmonares/complicaciones , Neoplasias Pulmonares/cirugía , Isquemia Miocárdica/complicaciones , Isquemia Miocárdica/cirugía , Neumonectomía , Anciano , Puente Cardiopulmonar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Respiración Artificial , Resultado del TratamientoRESUMEN
Percutaneous balloon dilatation has been used successfully to dilate various stenoses occurring after repair of congenital heart disease. Acute dissection of a stenotic right ventricular outflow tract occurred after attempted balloon dilatation in a patient with previously corrected tetralogy of Fallot.
Asunto(s)
Cateterismo/efectos adversos , Lesiones Cardíacas/etiología , Tetralogía de Fallot/cirugía , Obstrucción del Flujo Ventricular Externo/terapia , Preescolar , Femenino , Humanos , Recurrencia , Factores de Tiempo , Obstrucción del Flujo Ventricular Externo/etiologíaRESUMEN
Congenital oesophageal respiratory tract fistula presenting in adult life is rare. A tracheo-oesophageal and a broncho-oesophageal fistula presenting in a 22 year old female and 68 year male, respectively, are described. In both, symptoms of chronic recurrent pulmonary suppuration were initially attributed to alternative aetiologies, resulting in diagnostic delay and inappropriate management. Correct diagnosis was established by flexible bronchoscopy and oesophageal contrast studies. Surgical division of fistulae resulted in complete symptom resolution.
Asunto(s)
Fístula Bronquial/congénito , Fístula Esofágica/congénito , Fístula Traqueoesofágica/congénito , Adulto , Anciano , Fístula Bronquial/diagnóstico , Fístula Bronquial/cirugía , Broncoscopía , Fístula Esofágica/diagnóstico , Fístula Esofágica/cirugía , Esófago/diagnóstico por imagen , Femenino , Humanos , Masculino , Radiografía , Fístula Traqueoesofágica/diagnóstico , Fístula Traqueoesofágica/cirugíaRESUMEN
Neoplasms arising from smooth muscle of the gastrointestinal (GI) tract are uncommon, comprising only 1% of gastrointestinal tumours. A total of 51 cases of smooth muscle tumour of the GI tract were analysed; 44 leiomyomas and 7 leiomyosarcomas. Lesions occurred in all areas from the oesophagus to the rectum, the stomach being the commonest site. Thirty-six patients had clinical features referable to the tumour. The tumour was detected during investigation or management of an unrelated disease process in 15 patients. The clinical presentation varied depending on tumour location, but abdominal pain and GI bleeding were the commonest presenting symptoms. The lesion was demonstrated preoperatively, mainly by endoscopy and barium studies, in 27 patients. Surgical excision was the treatment of choice, where possible. There was no recurrence in the leiomyoma group but four patients died in the leiomyosarcoma group. Although rare, smooth muscle tumours should be considered in situations where clinical presentation and investigations are not suggestive of any common GI disorder. The preoperative assessment and diagnosis is difficult because of the variability in clinical features and their inaccessibility to routine GI investigation. It is recommended that, where possible, the lesion, whether symptomatic or discovered incidentally, should be excised completely to achieve a cure and prevent future complications.