RESUMEN
OBJECTIVE: Evaluate plasma markers of myocardial function and ischemia [B-type natriuretic peptide] (BNP) and cardiac troponin T (cTnT)] in relationship to echocardiographic indices of left ventricular (LV) function and severity of illness score (SNAPPE-II) in Very-Low-Birth-Weight-Infants (VLBWIs) prospectively. STUDY DESIGN: Serial echocardiography studies, clinical data, BNP and cTnT were obtained in thirty VLBWIs on postnatal days 1, 2, 3 and 7. RESULTS: BNP increased and cTnT decreased significantly day 1 through 3. BNP was significantly associated with patent ductus arteriosus (PDA), but did not correlate with LV function or cTnT and did not reflect use of inotropic medication. Cardiac troponin T increased with severity of illness, SNAPPE-II, score and was highest in babies receiving inotropic medication; Low cardiac output (CO) was common in the first seventy two hours and correlated negatively with cTnT (p < 0.01). A contractility index, the corrected LV mean velocity of circumferential fiber shortening, (mVcfc) was not related to cTnT. The LV mVcfc was inversely related to LV end systolic wall stress (p < 0.001) in all subgroups, and this index of contractility (mvcfc-ess) did not differ with large caliber PDA or use of inotropic medication. CONCLUSION: Cardiac troponin T exclusively rather than a combined biomarker approach may be useful in assessing myocardial injury. Cardiac output was low in sick VLBWIs with myocardial ischemia. Left ventricular contractile state was apparently preserved in significantly ill babies with elevated cTnT. Further research is needed to define the complex relationship between biomarkers and echocardiographic indices.
Asunto(s)
Conducto Arterioso Permeable/diagnóstico por imagen , Enfermedades del Prematuro/diagnóstico por imagen , Recién Nacido de muy Bajo Peso , Péptido Natriurético Encefálico/sangre , Troponina T/sangre , Disfunción Ventricular Izquierda/diagnóstico por imagen , Biomarcadores/sangre , Conducto Arterioso Permeable/sangre , Femenino , Humanos , Recién Nacido , Recien Nacido Prematuro , Enfermedades del Prematuro/sangre , Recién Nacido de muy Bajo Peso/sangre , Recién Nacido de muy Bajo Peso/fisiología , Modelos Logísticos , Masculino , Índice de Severidad de la Enfermedad , Método Simple Ciego , Ultrasonografía , Disfunción Ventricular Izquierda/sangreRESUMEN
Echocardiographic methods based on geometric models have long been in use for estimating left ventricular mass, but there is currently no similar method for estimating right ventricular (RV) free-wall mass. We hypothesized that a one-quarter prolate ellipsoid model could be used with two-dimensional echocardiography to approximate RV mass. Over a 2-year period 39 patients who had both a complete cardiac magnetic resonance imaging (MRI) scan and an echocardiogram within 2 weeks of each other were retrospectively analyzed. MRI-derived RV mass was used as the standard for comparison. Echocardiographic RV mass was estimated using three equations based on the geometric model. Linear regression analysis was performed to determine the correction factors used in the final formulae. The formula with the lowest standard error of the estimate was then prospectively analyzed for accuracy using a separate group of 88 subjects. The most accurate echocardiographic equation derived was RV mass = 5.84 (apical four-chamber RV cavity planar area) (RV free-wall thickness) + 1. Compared to MRI-RV mass the correlation coefficient was 0.97 and the standard error of the estimate was 16.8%. The positive and negative predictive values for diagnosing RV hypertrophy were 95% and 88%, respectively. We conclude that RV free-wall mass can be estimated by two-dimensional echocardiography using a one-quarter prolate ellipsoid shell model.
Asunto(s)
Ecocardiografía/métodos , Hipertrofia Ventricular Derecha/diagnóstico por imagen , Adolescente , Algoritmos , Niño , Preescolar , Femenino , Ventrículos Cardíacos/diagnóstico por imagen , Humanos , Lactante , Recién Nacido , Imagen por Resonancia Magnética , Masculino , Estudios Prospectivos , Análisis de Regresión , Estudios RetrospectivosRESUMEN
OBJECTIVES: This study sought to establish and maintain patency of the ductus arteriosus by a new method of transvascular formalin infiltration of the ductus arteriosus wall. BACKGROUND: Maintaining patency of the ductus arteriosus postnatally is necessary with many forms of congenital heart disease to ensure survival until definitive surgical repair. A variety of approaches have to date met with variable success. METHODS: Seven newborn lambs underwent catheterization at 1 to 5 days of age. A functionally closed ductus arteriosus was traversed with a specially designed porous balloon catheter, and the wall was infiltrated with 10% formalin. The ductus was then further dilated with either a 7- or 8-mm diameter balloon. RESULTS: The ductus arteriosus wall was successfully infiltrated and dilated in all animals. Two lambs were euthanized within 24 h with congestive heart failure from a large ductus, and one lamb was electively euthanized 5 days after transvascular infiltration. Four lambs underwent serial follow-up catheterizations, one of which required repeat balloon dilation 47 days after infiltration. At latest follow-up (mean age [+/- 1 SD] 83 +/- 34 days, range 33 to 108), the pulmonary/systemic flow ratio (2.7 +/- 1.2) was unchanged from immediately after infiltration (1.9 +/- 0.5, p > 0.1). The narrowest diameter of the ductus arteriosus (4.3 +/- 0.4 mm vs. 6.9 +/- 2.6 mm, p > 0.1) and its ratio to that of the adjacent descending aorta (0.5 +/- 0.1 vs 0.4 +/- 0.1, p > 0.1) were also unchanged at latest follow-up. No systemic toxicity was observed. At postmortem study, the ductus was patent, and histologic analysis showed variable intimal and medial destruction, endothelial regeneration, loss of elastic tissue and calcification. Adjacent pulmonary artery and aorta were normal. Based on the small sample size and the observed maximal effect size of 70%, the power of the study is at most 40% to detect significant differences. CONCLUSIONS: To our knowledge, this is the first time that transvascular formalin infiltration of the ductus arteriosus wall has been applied successfully to maintain ductal patency in the newborn lamb. This method may provide a means of palliation for neonates with certain forms of congenital heart disease.
Asunto(s)
Cateterismo/instrumentación , Conducto Arterioso Permeable/fisiopatología , Conducto Arterial/efectos de los fármacos , Formaldehído/administración & dosificación , Animales , Animales Recién Nacidos , Cateterismo/métodos , Conducto Arterial/diagnóstico por imagen , Conducto Arterial/fisiología , Conducto Arterioso Permeable/diagnóstico por imagen , Diseño de Equipo , Estudios de Factibilidad , Formaldehído/farmacología , Radiografía , Ovinos , Grado de Desobstrucción Vascular/efectos de los fármacosRESUMEN
The atypical presentation of CATCH 22 raises several important concerns. First, in this patient, as in others, the heart defects were found in association with subtle facial abnormalities but with few of the other criteria normally seen in CATCH 22. This association alone may be sufficient to raise suspicion that an interstitial 22q11 deletion may be present. Second, the incidence of chromosome 22 deletions in parents of children with a 22q11 deletion (25%) suggests that siblings or subsequent fetuses may also be at risk. Parents with subtle or unusual manifestations of CATCH 22 may be unaware of their potential carrier status. Finally, the recognition of chromosomal mosaicism in this patient may have been fortuitous, as cytogenetic studies of leukocytes from other individuals with a mosaic karyotype may sometimes fail to reveal a 22q11 deletion that is present in cardiac tissues. Molecular cytogenetic analysis of cardiac specimens that are removed during routine surgical procedures may be warranted in appropriate clinical situations.
Asunto(s)
Deleción Cromosómica , Cromosomas Humanos Par 22/genética , Cara/anomalías , Cardiopatías Congénitas/genética , Síndrome del Corazón Izquierdo Hipoplásico/genética , Mosaicismo , Resultado Fatal , Femenino , Humanos , Recién Nacido , Recién Nacido Pequeño para la Edad Gestacional , Fenotipo , SíndromeRESUMEN
The current strategies concerning a small (=2 mm) patent ductus arteriosus (PDA) include surgical ligation, transcatheter implantation of the Rashkind occluder device, or no intervention requiring indefinite endocarditis precautions. Five patients have undergone successful transcatheter closure of a small-caliber PDA utilizing a single 3 mm Gianturco occluder coil as an alternative to surgical ligation. The coil was delivered to traverse the narrowest dimension of the PDA, leaving loops of coil in both the pulmonary and aortic ends of the ductus. All PDAs were successfully occluded, and the duration of hospitalization for all patients was 1 day. At latest follow-up (11 +/- 2 months), echocardiography demonstrates complete ductus occlusion in all patients, with no obstruction to left pulmonary arterial or descending aortic flow. Transcatheter coil occlusion of the small ductus is an easily accomplished, safe, effective alternative to surgical ligation, thereby avoiding a lateral thoracotomy incision, shortening hospitalization, and reducing costs.
Asunto(s)
Cateterismo Cardíaco , Conducto Arterioso Permeable/terapia , Embolización Terapéutica/métodos , Aorta Torácica/diagnóstico por imagen , Niño , Angiografía Coronaria , Conducto Arterioso Permeable/diagnóstico , Ecocardiografía , Estudios de Seguimiento , Humanos , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
Assessment of the hemodynamic and anatomic results following balloon angioplasty of discrete native coarctation of the aorta, with particular attention to "remodeling," has required repeat cardiac catheterization and angiography, which is invasive and has limited resolution. Eight patients with hypertension and discrete native coarctation with an otherwise normally developed aortic arch underwent angioplasty at 5.0 +/- 6.8 years of age. Angiographic cross-sectional areas of the aorta indexed to body surface area at the isthmus (I), coarctation site (C), and 1 cm distal to the coarctation site (Cd) pre- and postangioplasty were compared with MRI-indexed cross-sectional areas 18 +/- 10 months (MRI-1) and 35 +/- 11 months (MRI-2) postangioplasty. From preangioplasty to MRI-2, the isthmus was smaller (149 +/- 22 versus 127 +/- 27 mm2/m2; p < 0. 05). The coarctation site was larger postangioplasty (25 +/- 9 versus 116 +/- 40 mm2/m2; p < 0.001) with continued growth at latest follow-up (116 +/- 40 versus 164 +/- 36 mm2/m2; p < 0.01). The segment 1 cm distal to the coarctation site continued to decrease in area at latest follow-up (267 +/- 78 versus 163 +/- 38 mm2/m2; p < 0. 001). I versus C versus Cd at MRI-2 were similar, whereas postangioplasty and MRI-1 cross-sectional area measurements were significantly different. Following angioplasty of discrete native coarctation, the aorta becomes more uniform or undergoes "remodeling." Noninvasive MRI is an effective means of evaluating the anatomic result following balloon angioplasty, obviating the need for repeated invasive cardiac catheterizations.
Asunto(s)
Angioplastia de Balón , Aorta/patología , Coartación Aórtica/diagnóstico , Coartación Aórtica/terapia , Adolescente , Adulto , Aorta/fisiopatología , Coartación Aórtica/fisiopatología , Aortografía , Arteriopatías Oclusivas/diagnóstico , Arteriopatías Oclusivas/fisiopatología , Presión Sanguínea , Cateterismo Cardíaco , Niño , Preescolar , Estudios de Seguimiento , Humanos , Lactante , Imagen por Resonancia Magnética , Estudios RetrospectivosRESUMEN
We have studied the neurodevelopmental outcome of 104 consecutive unselected children who underwent open-heart surgery from 1987 through 1989. Survivors had formal neurologic and psychometric examinations after 2 years of age. Mean IQ was 90, and 78% had scores above 70. Cerebral palsy occurred in 22%. Deep hypothermia for longer than 45 minutes was associated with IQ less than 85 (P < .001) and later cerebral palsy (P = .02). Those less than 1 month old at operation had a median IQ of 96, and 25% had cerebral palsy. Median IQ for survivors of hypoplastic left heart syndrome was 66, only one had an IQ above 70, and 57% had cerebral palsy. Median IQ for transposition of great arteries was 109, only one was less than 85, and all had normal neurologic examinations. Those between 1 and 6 months of age at operation had a median IQ of 93, with 64% above 85, and 5% had cerebral palsy. Those older than 6 months had a median IQ of 99, with 70% above 85, and 13% had cerebral palsy. For infants less than 1 month old at operation, a strong association existed between outcome, type of lesion, and duration of deep hypothermia (P < .01), although not in all cases. In those older than 1 month at operation, no association existed between outcome and any study variable. Although the majority of children have an uneventful outcome after open-heart surgery, a significant morbidity exists. This is related to several factors, including type of lesion and duration of hypothermia, particularly in neonates; preoperative congenital and acquired lesions; and possible perioperative cerebrovascular events.
Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Cardiopatías Congénitas/cirugía , Factores de Edad , Procedimientos Quirúrgicos Cardíacos/mortalidad , Procedimientos Quirúrgicos Cardíacos/psicología , Puente Cardiopulmonar , Preescolar , Humanos , Lactante , Recién Nacido , Examen Neurológico , Psicometría , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del TratamientoRESUMEN
OBJECTIVE: To ascertain the relation between postoperative neurologic complications and variables occurring before, during, and after hypothermic cardiopulmonary bypass surgery to correct congenital heart disease in young infants. DESIGN: Prospective analysis of mortality and neurologic morbidity before hospital discharge; systematic comparison with patient characteristics, metabolic status, surgery variables; and preoperative neurologic findings of the patients. SETTING: Intensive care unit in tertiary care center. PATIENTS: Consecutive sample of 91 full-term infants who underwent 100 operations between January 1989 through December 1992. Nine infants had more than one operation during the study period. MAIN OUTCOME MEASURES: Levels of alertness, tone, focal signs, dyskinesia, pyramidal signs, seizures, and death. RESULTS: Reduced level of alertness at discharge from the hospital in 19% of patients; seizures in 15% (70% focal); severe hypotonia in 11% before surgery, and in 7% at discharge from hospital; generalized pyramidal findings in six (7%); asymmetry of tone in 5%; and chorea that did not persist in 11%. Results of cranial ultrasound tests were abnormal in 20% of patients. Of these those with abnormal cranial ultrasound examinations 55% were abnormal before surgery. Overall mortality was 18%. Of the patients who died, 59% had interrupted aortic arch or hypoplastic left heart syndrome. Mortality for patients with these lesions was 40%. Alertness (P = .005), chorea (P = .03), and hypotonia (P = .02) were associated with duration of deep hypothermia longer than 60 minutes. No association was found among other outcomes and study variables, except the relation between severe left-sided heart lesions and mortality. CONCLUSIONS: Mortality and neurologic morbidity after open heart surgery on young infants may be due to several factors, including type of lesion, preexisting brain abnormalities, duration of deep hypothermia, and strokes.
Asunto(s)
Puente Cardiopulmonar/efectos adversos , Cardiopatías Congénitas/cirugía , Hipotermia Inducida/efectos adversos , Enfermedades del Sistema Nervioso/etiología , Complicaciones Posoperatorias/etiología , Encéfalo/patología , Ecoencefalografía , Paro Cardíaco Inducido/efectos adversos , Humanos , Lactante , Recién Nacido , Examen Neurológico , Estudios ProspectivosRESUMEN
From April 1987 to September 1993, 60 infants underwent a Norwood operation for complex congenital heart disease including hypoplastic left heart syndrome (n = 41), ventricular septal defect and subaortic stenosis with aortic arch interruption/severe coarctation (n = 7), complex single right ventricle with subaortic stenosis (n = 8), critical aortic stenosis with endocardial fibroelastosis (n = 2), and malaligned primum atrial septal defect with coarctation (n = 2). Age at operation ranged from 1 day to 3.9 months (mean 9 days, median 3.5 days). The operative mortality (< 30 days) was 33% (20 patients). Late mortality was 17% (10 patients). Nine of the 20 (45%) operative deaths occurred during the first 2 days after the operation as a result of sudden hemodynamic instability. All four infants with premature closure of the foramen ovale had pulmonary lymphangiectasia and died of pulmonary failure. Seven operative deaths have occurred in 36 patients since 1990 (19%); in the past 2 years, no operative deaths have occurred in 22 patients. Overall, there are 30 long-term survivors (50%). Twenty-one of these 30 infants have undergone a two-stage repair with a modified Fontan operation at 7.3 to 27.6 months of age (mean 18.1 months) with no mortality. Six patients have entered a three-stage repair strategy by undergoing a hemi-Fontan procedure at 6.8 to 23.0 months (mean 8.8 months) with no mortality, and two of these patients have now had their modified Fontan operation at 23.0 to 46.7 months of age with no mortality (four are still awaiting surgery). Two patients have undergone a two-ventricle repair with a Rastelli procedure, with no mortality at 7.4 and 14.1 months of age. Early in our experience, infants undergoing the Norwood operation had a high early mortality most often related to sudden hemodynamic instability. After we instituted a protocol that adds carbon dioxide to the inspired gas during postoperative mechanical ventilation, the postoperative course became more stable and there have been no operative deaths. In summary, the operative mortality for the Norwood operation continues to improve. A subsequent Fontan operation can be performed with excellent clinical results.
Asunto(s)
Procedimiento de Fontan , Cardiopatías Congénitas/cirugía , Procedimientos Quirúrgicos Cardíacos/métodos , Procedimientos Quirúrgicos Cardíacos/mortalidad , Femenino , Cardiopatías Congénitas/mortalidad , Cardiopatías Congénitas/fisiopatología , Hemodinámica , Humanos , Lactante , Recién Nacido , Masculino , Tasa de SupervivenciaRESUMEN
We performed magnetic resonance imaging (MRI) on the brain and neurologic examinations on 23 children after open heart surgery for congenital heart disease. Twenty children also had psychometric assessments. Examinations were performed at a mean age of 66 months (range, 26 to 180 months). Age at operation was less than 1 month in 43% and more than 6 months in 45%. Abnormal scans were found in 17 (74%) and showed diffuse findings consistent with hypoxic-ischemic encephalopathy, with or without areas of cortical infarction; focal cortical infarction alone; and (in one patient) callosal agenesis and abnormal neuronal migration. Normal IQ and neurologic examinations were found in all six of those who had a normal MRI, and five of six children with changes consistent with focal cortical infarction without diffuse change had a normal neurologic examination. Cerebral palsy and mental retardation was common in the group with diffuse abnormality (in eight of nine children), and this was more likely to occur in those who underwent prolonged (> 45 minutes) hypothermic circulatory arrest and operation during early infancy (P = .004). Focal cortical findings without diffuse changes were more likely in those who underwent open heart surgery without hypothermic circulatory arrest and were older than 6 months at operation, and these children were less likely to have frank neurodevelopmental sequelae. Thus, in our population, focal cortical lesions were common after open heart surgery, and, in addition, diffuse brain abnormality on MRI plus neurologic sequelae were common after prolonged hypothermic circulatory arrest.
Asunto(s)
Daño Encefálico Crónico/diagnóstico , Cardiopatías Congénitas/cirugía , Imagen por Resonancia Magnética , Complicaciones Posoperatorias/diagnóstico , Adolescente , Encéfalo/patología , Infarto Cerebral/diagnóstico , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Hipoxia Encefálica/diagnóstico , Lactante , Recién Nacido , Inteligencia/fisiología , Masculino , Examen NeurológicoRESUMEN
Hypertrophic cardiomyopathy and abnormal ventricular diastolic filling in the infant of the diabetic mother is related to poor maternal glycemic control. Evaluation of fetuses of well controlled diabetic mothers has not been examined. Eleven fetuses of nondiabetic mothers (normals) and 9 fetuses of well controlled insulin-dependent diabetic mothers (FODMs) underwent serial evaluation of cardiac growth and ventricular diastolic filling using M-mode and Doppler echocardiography at 20-26 weeks' (period 1), 27-33 weeks' (period 2), 34-40 weeks' (period 3),m and 48-72 hours after birth (period 4). Indices of right and left ventricular diastolic filling included time velocity integral ratios (E/A and %E/E+A). Cardiac growth and birth weight in the two groups were similar consistent with "good" glycemic control. This conclusion was supported by similar maternal glycosylated hemoglobin (%A1C) prenatally and newborn %A1C and C-peptide values postnatally. Heart rate before and after birth and placental resistance prenatally were similar. Both normals and FODMs demonstrated an increase in left ventricular E/A and %E/E+A ratios from period 1 to 4 (p < 0.0001). This shift occurred earlier (by period 2) in normals (p < 0.01). Right ventricular filling ratios increased by period 4 in normals only (p < 0.01). No differences were noted between the groups during any period. Good glycemic control in FODMs results in normal cardiac growth and ventricular diastolic filling. Progression of diastolic filling is abnormally delayed, however, and is presumably more exaggerated in poorly controlled diabetics.
Asunto(s)
Diabetes Mellitus Tipo 1/diagnóstico por imagen , Corazón Fetal/crecimiento & desarrollo , Embarazo en Diabéticas/diagnóstico por imagen , Ultrasonografía Prenatal , Función Ventricular Izquierda/fisiología , Función Ventricular Derecha/fisiología , Peso al Nacer , Glucemia/metabolismo , Péptido C/sangre , Cardiomiopatía Hipertrófica/diagnóstico por imagen , Cardiomiopatía Hipertrófica/fisiopatología , Diástole/fisiología , Ecocardiografía Doppler , Femenino , Edad Gestacional , Hemoglobina Glucada/metabolismo , Frecuencia Cardíaca/fisiología , Humanos , Recién Nacido , Contracción Miocárdica/fisiología , Embarazo , Valores de Referencia , Factores de RiesgoAsunto(s)
Arginina , Cardiomiopatía Hipertrófica/genética , ADN/genética , Glutamina , Miocardio/metabolismo , Miosinas/genética , Mutación Puntual , Secuencia de Aminoácidos , Secuencia de Bases , Mapeo Cromosómico , Cromosomas Humanos Par 1 , Cromosomas Humanos Par 11 , Cromosomas Humanos Par 14 , Cromosomas Humanos Par 15 , ADN/sangre , Cartilla de ADN , Femenino , Humanos , Masculino , Datos de Secuencia Molecular , Linaje , Reacción en Cadena de la Polimerasa/métodos , Valores de ReferenciaRESUMEN
In a prospective study, we analyzed the intraoperative electroencephalographic (EEG) changes during open heart surgery with deep hypothermia in 66 infants aged 6 months or younger, 70% of whom were neonates. Suppression of amplitude and continuity at the nadir of temperature reduction and following rewarming, and the appearance of periodic paroxysmal activity, was compared with neurologic abnormalities before and following operation, patient characteristics, and operation variables. EEG changes disclosed no relationship to abnormal neurologic findings, age at operation, type of anesthetic, duration of cardiopulmonary bypass (CPB), duration of low-flow CPB or cooling, temperature at circulatory arrest (HCA) or low flow, or nasopharyngeal-venous return temperature differences. EEG suppression following rewarming was associated with the use of thiopentone and duration of HCA. Use of thiopentone was also related to decreased levels of alertness at the end of the first postoperative week. We could not demonstrate any association between operation variables, including duration of HCA, and postoperative neurologic findings which include abnormalities of tone, alertness, seizures, generalized pyramidal signs, choreoathetosis, and hemiparesis. Severe hypotonia before operation was associated with continuing severe hypotonia during the postoperative period. EEG changes during cooling for open heart surgery on infants appear to be physiologic, and these plus EEG suppression following HCA or low-flow CPB are not useful predictors of early neurologic morbidity.
Asunto(s)
Daño Encefálico Crónico/fisiopatología , Electroencefalografía , Cardiopatías Congénitas/cirugía , Complicaciones Intraoperatorias/fisiopatología , Monitoreo Intraoperatorio , Examen Neurológico , Daño Encefálico Crónico/diagnóstico , Daño Encefálico Crónico/mortalidad , Potenciales Evocados/fisiología , Femenino , Estudios de Seguimiento , Cardiopatías Congénitas/mortalidad , Cardiopatías Congénitas/fisiopatología , Humanos , Lactante , Recién Nacido , Complicaciones Intraoperatorias/diagnóstico , Complicaciones Intraoperatorias/mortalidad , Masculino , Hipotonía Muscular/diagnóstico , Hipotonía Muscular/fisiopatología , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/mortalidad , Complicaciones Posoperatorias/fisiopatología , Estudios Prospectivos , Espasmos Infantiles/diagnóstico , Espasmos Infantiles/fisiopatología , Análisis de SupervivenciaAsunto(s)
Aorta/diagnóstico por imagen , Ecocardiografía Doppler , Prueba de Esfuerzo , Adolescente , Niño , Ecocardiografía Doppler/métodos , Ecocardiografía Doppler/estadística & datos numéricos , Prueba de Esfuerzo/estadística & datos numéricos , Femenino , Hemodinámica , Humanos , Masculino , Valores de Referencia , SístoleRESUMEN
Neutropenia is an infrequent complication following administration of the angiotensin-converting enzyme (ACE) inhibitor, captopril. Most reports have been in adult patients, with rare reports in the pediatric population. We report two cases of neutropenia following captopril use in cardiac patients with trisomy 21. As this was not seen in patients without Down's syndrome, we postulate that patients with trisomy 21 have bone marrow which is "at risk" for suppression, and, thus warrant close evaluation while on such medications.
Asunto(s)
Médula Ósea/efectos de los fármacos , Captopril/efectos adversos , Síndrome de Down/complicaciones , Cardiopatías Congénitas/genética , Neutropenia/inducido químicamente , Captopril/uso terapéutico , Femenino , Cardiopatías Congénitas/cirugía , Insuficiencia Cardíaca/tratamiento farmacológico , Humanos , Hipertensión/tratamiento farmacológico , Lactante , Masculino , Cuidados PosoperatoriosRESUMEN
We previously reported developmental differences in the response of cytosolic free calcium ([Cai]) to extracellular potassium ([Kex]) depolarization (cardioplegia) in juvenile (4 weeks post partum) and mature (12 to 18 months post partum) cardiac myocytes (rabbit). Our present study explored the physiologic basis for these observations. Single calcium-tolerant cardiac myocytes were isolated by sequential exposure to proteolytic agents, loaded with a fluorescent probe for calcium (fura-2) and [Cai] measured by standard fluorescence techniques. The response of [Cai] to [Kex] depolarization (30 mmol/L) was determined in the presence of varying levels of extracellular calcium [Caex], verapamil, ouabain, and amiloride. At nominal levels of [Caex] (0 mmol/L), no significant increases in [Cai] from the juvenile (2.1% +/- 3.3%) or mature (8.5% +/- 3.1%) myocytes were seen. At increasing [Caex], there was a progressive increase in the response of [Cai] to [Kex] depolarization in mature animals' cells (191.8% +/- 40.7%) but not in the juveniles' cells (28.0% +/- 11.5%). Exposure to verapamil resulted in an approximate 80% reduction in relative increase in [Cai] in the mature compared with 60% in the juvenile myocytes. Finally, ouabain exposure resulted in a significant increase in the relative change of [Cai] in juvenile cells (30% to 126.4% +/- 39.4%) but not in the adults' cells. This increase in the juvenile myocytes was blocked by amiloride. We conclude that increases in cardiac myocyte [Cai] after [Kex] depolarization occur predominantly through the calcium channel in the mature animal and through sodium-calcium exchange in the juvenile.
Asunto(s)
Envejecimiento/metabolismo , Calcio/metabolismo , Paro Cardíaco Inducido , Homeostasis , Miocardio/metabolismo , Amilorida/farmacología , Animales , Calcio/farmacología , Citosol/metabolismo , Electrofisiología , Fura-2/farmacología , Corazón/fisiología , Técnicas In Vitro , Miocardio/citología , Ouabaína/farmacología , Potasio/metabolismo , Conejos , Sarcolema/metabolismo , Retículo Sarcoplasmático/metabolismo , Verapamilo/farmacologíaRESUMEN
The mechanism for exercise systolic hypertension after a "good" operative repair of coarctation of the aorta remains speculative. Twenty-four children (mean age +/- SD 10.3 +/- 3.8 years) were studied with continuous-wave Doppler echocardiography while they performed continuous, graded, maximal treadmill exercise. Patients were free of "recoarctation" based on conventional resting echocardiography. Measurements of ascending and descending aortic peak instantaneous systolic velocity were obtained at rest, throughout exercise and during recovery. Results were compared with 24 age- and gender-matched control subjects. Fifteen patients were normotensive (group 1) (peak systolic blood pressure, 147 +/- 21 mm Hg) and 9 developed systolic hypertension during exercise (group 2) (196 +/- 32 mm Hg) (p < 0.05) (control subjects, 143 +/- 21 mm Hg). Descending aortic peak systolic velocity at rest ranged from 1.50 +/- 0.27 m/s in the control group to 2.57 +/- 0.57 m/s (group 1) and 2.93 +/- 0.43 m/s (group 2) (p < 0.05, group 2 vs control). Differences were amplified at peak exercise with systolic velocity increasing to 4.26 +/- 0.61 m/s in group 2 but only to 3.61 +/- 0.70 m/s in group 1 and 2.26 +/- 0.38 m/s in control subjects (p < 0.05, group 2 vs group 1 and control). Seven patients developed a descending aortic diastolic velocity during exercise. Stepwise linear regression analysis identified 2 variables to be significant determinants of peak exercise systolic blood pressure in the "total" patient group: (1) age at exercise testing, and (2) descending aortic peak systolic velocity at peak exercise (r2 = 0.88, p < 0.001) (group 2, alone - r2 = 0.98, p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Coartación Aórtica/cirugía , Ecocardiografía Doppler , Prueba de Esfuerzo , Hipertensión/diagnóstico por imagen , Complicaciones Posoperatorias/diagnóstico por imagen , Adolescente , Adulto , Aorta Torácica/diagnóstico por imagen , Aorta Torácica/fisiopatología , Coartación Aórtica/diagnóstico por imagen , Coartación Aórtica/fisiopatología , Velocidad del Flujo Sanguíneo , Presión Sanguínea , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Humanos , Hipertensión/etiología , Hipertensión/fisiopatología , Modelos Lineales , Masculino , Complicaciones Posoperatorias/fisiopatología , Recurrencia , Sístole/fisiologíaRESUMEN
OBJECTIVES: This study was conducted to evaluate the incidence and etiology of hypertension and aortic arch gradients during exercise in patients who have apparent good coarctation repair assessed at rest. BACKGROUND: The reported incidence of recurrent aortic arch obstruction (rest gradient > 20 mm Hg) after previous successful surgical repair varies from 0% to 60% and usually is associated with recurrent stenosis at the site of surgical repair. METHODS: Maximal treadmill exercise with Doppler echocardiographic gradient estimation was performed in 28 patients with a good coarctation repair at rest (normal blood pressure and arch gradient < 20 mm Hg) who had isolated coarctation repair a mean of 7.8 years previously. RESULTS: Eight (29%) developed systolic hypertension for age and a mean Doppler gradient of 45 +/- 13 mm Hg. At cardiac catheterization, the rest peak to peak systolic gradient (6 +/- 6 to 28 +/- 7 mm Hg, p < 0.001), peak systolic instantaneous gradient (16 +/- 11 to 48 +/- 9 mm Hg, p < 0.01) and cardiac index (3.5 +/- 0.7 to 5.9 +/- 1.1 liters/m per m2, p < 0.001) all increased during isoproterenol infusion. Angiographic systolic aortic arch measurements proximal to the innominate artery, left common carotid artery, left subclavian artery and the narrowest dimension at the coarctation repair site demonstrated hypoplasia at the left common carotid artery (11.8 +/- 1.7 vs. 16.7 +/- 2.9 mm/m2, p < 0.01) and left subclavian artery (11.6 +/- 1.7 vs. 15.4 +/- 3.1 mm/m2, p < 0.05) compared with findings in 10 patients with normal aortograms. Transverse aortic arch ratios were also smaller in the eight patients with abnormal findings. Preoperative angiographic ratios were not predictive of late postoperative findings. CONCLUSIONS: Exercise testing detects hypertension and arch gradients in patients with a good coarctation repair as assessed at rest. The hypertension and arch "obstruction" appear to be related to discrepancies in the growth of the transverse aortic arch proximal to the repair site, rather than a "recoarctation" of the aorta.