RESUMEN
UNLABELLED: Cardiotoxicity is a well recognized complication of anthracycline (AC) therapy. Subtle abnormalities in myocardial function that become apparent only after exercise may exist in survivors of childhood cancer who have previously received AC, yet have normal resting cardiac function. To evaluate if anesthesia-induced changes in cardiac function differ in pediatric patients with previous AC therapy from healthy children and adolescents, we evaluated in a prospective study 43 patients, of whom 42 were analyzed. Twenty-one patients (AC-group), mean age 9.6 yr (range, 3-16 yr), who had received 193 (30-490) mg/m(2) of AC as a mean cumulative dose with normal resting cardiac function (shortening fraction [SF] 0.34, normal value > 0.30) underwent removal of a Hickman catheter under general anesthesia. Twenty-one patients, mean age 10.9 yr (range, 4-17 yr), who underwent placement of a Hickman catheter before chemotherapy served as the control. All children were premedicated with midazolam 0.5 mg/kg orally. Anesthesia was induced by sodium thiopental (5 mg/kg), fentanyl (3 micro g/kg), and rocuronium (0.6 mg/kg) and maintained with isoflurane (1 MAC) in N(2)O/O(2) (70/30). Before induction (baseline), 5 and 20 min after intubation (T1 and T2), and 20 min after extubation (control), cardiac function was assessed by transthoracic (baseline, control) and transesophageal (T1, T2) echocardiography. Compared with baseline (SF: 34.9 +/- 3.7 [AC], 34.1 +/- 3.7 [C] [not significant]; stroke volume index [SVI] 36 +/- 6 mL/m(2)[AC], 35 +/- 4 mL/m(2)[C] [not significant]; cardiac index [CI] 3.6 +/- 0.6 L/min/m(2)[AC], 3.2 +/- 0.5 L/min/m(2)[C] [not significant]), we found a significant decrease in SF and SVI in both groups at T1 (SF: 26.2 +/- 3.6 [AC] versus 28.6 +/- 3.6 [C] [P < 0.05]; SVI: 26 +/- 4 mL/m(2) [AC] versus 30 +/- 46 mL/m(2) [C] [P < 0.05]) and T2 (SF: 24.1 +/- 3.2 [AC] versus 28.2 +/- 2.5 [C] [P < 0.01], SVI: 26 +/- 6 mL/m(2) [AC] versus 31 +/- 5 mL/m(2) [C] [P < 0.01]), which was significantly greater in the AC group. There were no significant changes of variables of diastolic function (E/A ratio, isovolumetric relaxation time) between both groups. Previous treatment with AC may enhance the myocardial depressive effect of anesthetics even in patients with normal resting cardiac function. IMPLICATIONS: Previous treatment with anthracylines, a group of chemotherapeutic drugs in use for childhood cancer, may enhance the myocardial depressive effect of anesthetics even in children and adolescents with normal resting cardiac function.
Asunto(s)
Anestesia General , Antraciclinas/efectos adversos , Antineoplásicos/efectos adversos , Corazón/efectos de los fármacos , Adolescente , Niño , Preescolar , Terapia Combinada/efectos adversos , Ecocardiografía Transesofágica , Electrocardiografía/efectos de los fármacos , Femenino , Pruebas de Función Cardíaca , Hemodinámica/efectos de los fármacos , Humanos , Masculino , Monitoreo Intraoperatorio , Neoplasias/complicaciones , Neoplasias/tratamiento farmacológicoRESUMEN
OBJECTIVES: To investigate the changes of the fetal magnetocardiography (FMCG), a new noninvasive diagnostic tool in the analysis of electrophysiologic changes of the heart, in cases of congenital heart defect (CHD). METHODS: The FMCG was analysed and compared to the postnatal ECG in eight cases of CHD: atrial septal defect ASDII (three cases), a combination of atrioventricular-septal-defect (AVSD) and Tetralogy of Fallot (TOF) (one case ), complete transposition of great arteries (d-TGA) (two cases), coarctation of aorta (COA) (one case), stenosis of the pulmonary artery (PS) and right ventricular hypoplasia (one case). RESULTS: (1) The following FMCG changes were observed: a split R-wave (AVSD/TOF, ASDII), prolongation of QRS complex (COA, PS). (2) The notch of the R-wave could not be observed in the newborn with AVSD/TOF. (3) Neither the fetal FMCG nor the neonatal ECG revealed any changes in the cases of d-TGA. (4) All other neonatal ECGs were corresponding to the FMCG. CONCLUSIONS: The FMCG can unearth changes of the cardiac electrophysiologic activity in the case of CHD. The method provides additional information concerning the effect of a CHD on the cardiac conductory system. As in the neonate, the FMCG changes do not reflect the severity of the CHD. FMCG cannot serve as a primary diagnostic tool in the case of CHD as compared to echocardiography.