RESUMO
OBJECTIVE: We sought to evaluate contractile function in single-ventricle patients before and after imposition of Fontan physiology. METHODS: Single right ventricle (SRV; n = 38) and single left ventricle (SLV; n = 11) patients underwent cardiac magnetic resonance imaging pre and post Fontan operation. Global radial strain (GRS), global circumferential strain (GCS), and global longitudinal strain were measured along with ejection fraction (EF) and atrioventricular valve regurgitation (AVVR). RESULTS: Age at cardiac magnetic resonance imaging before the Fontan operation was 3.1 ± 1.3 years and after the Fontan procedure was 5.8 ± 2.7 years. There were no significant EF differences between SRV and SLV patients before and after the Fontan procedure, and EF did not deteriorate significantly after the Fontan operation. GRS was significantly lower for SRV patients than for SLV patients before (24.3% vs 32.1%; P = .048) and after (21.8% vs 29.7%; P = .045) the Fontan procedure. GRS and GCS of the SRV patients deteriorated significantly after the Fontan operation (GRS, P = .01; GCS, P = .009). Strains showed positive correlations before and after the Fontan operation with positive correlations among each strain. Within all patients, strains correlated positively with EF. Strains and EF negatively correlated with AVVR (GRS P = .03, r = -0.22; GCS P = .03, r = -0.23; EF P < .001, r = -0.37). CONCLUSIONS: Strains were lower for SRV than for SLV patients before and after the Fontan operation and deteriorated after the Fontan operation. Our study suggests that strain measures might detect ventricular deterioration earlier than EF. Because strains before and after the Fontan operation were positively correlated, and negatively correlated with AVVR, the early institution of myocardial protective therapy including AVVR management, especially for SRV patients, might have benefit.
Assuntos
Técnica de Fontan , Coração Univentricular/fisiopatologia , Coração Univentricular/cirurgia , Função Ventricular , Fenômenos Biomecânicos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Estudos Retrospectivos , Volume SistólicoRESUMO
OBJECTIVE: To identify mediators of health status and quality of life (QOL) in children and adolescents aged 8-18 years old following surgical repair for tetralogy of Fallot (TOF), including resource use, exercise performance, and 22q11.2 deletion status. STUDY DESIGN: We performed a corollary study to a cross-sectional analysis of subjects following repair for TOF that completed cardiac magnetic resonance imaging, cardiopulmonary exercise tests, and instruments assessing health status and QOL. General linear models were used to test for mediation. RESULTS: A total of 29 of 151 (19%) patients carried a 22q11.2 deletion. Parents of children with a deletion compared with those without a deletion reported worse physical and psychosocial functioning on the Child Health Questionnaire. The patients with a 22q11.2 deletion and their parents reported lower total and Disease Impact scores compared with the group without a deletion on the Pediatric Cardiac Quality of Life Inventory. Medical care use negatively correlated with measures of health status/QOL. Greater maximum work correlated with better patient health status and QOL, regardless of deletion status. Exercise performance mediated the association between deletion status and parent-reported outcomes (unstandardized effects ranging from 2.4 to 4.2) and patient-reported Disease Impact (0.99; 95% CI 0.02-2.70). CONCLUSION: Children and adolescents following repair for TOF seem to suffer significant challenges to their health status and QOL, which is amplified markedly in the context of the 22q11.2 deletion syndrome, and related to exercise performance.
Assuntos
Síndrome de DiGeorge/fisiopatologia , Exercício Físico/fisiologia , Qualidade de Vida/psicologia , Tetralogia de Fallot/fisiopatologia , Adolescente , Criança , Estudos Transversais , Síndrome de DiGeorge/complicações , Síndrome de DiGeorge/psicologia , Teste de Esforço , Feminino , Nível de Saúde , Humanos , Masculino , Inquéritos e Questionários , Tetralogia de Fallot/complicações , Tetralogia de Fallot/psicologiaRESUMO
BACKGROUND: Congestive hepatopathy is a recognized complication of Fontan physiology. Data regarding the incidence of hepatopathy and risk factors are lacking. METHODS AND RESULTS: Liver biopsies and cardiac catherizations were performed as part of an evaluation offered to all patients ≥10 years after Fontan. Quantitative determination of hepatic fibrosis was performed using Sirius red staining with automated calculation of collagen deposition per slide (%CD). Biopsies from included subjects were compared to stained specimens from controls without known fibrotic liver disease. Patient characteristics, echocardiographic findings, and hemodynamic measures were evaluated as potential risk factors. The cohort consisted of 67 patients (31 female) at mean age of 17.3±4.5 years and mean time from Fontan of 14.9±4.5 years. Right ventricular morphology was present in 37 subjects. Median %CD by Sirius red staining was 21.6% (range 8.7% to 49.4%) compared to 2.6% (range 2.2% to 3.0%) in controls. There was a significant correlation between time from Fontan and degree of Sirius red staining (r=0.33, P<0.01). Serum liver enzymes and platelet count did not correlate with %CD. The median inferior vena cava pressure was 13 mm Hg (range 6-24 mm Hg) and did not correlate with %CD. There was no difference in %CD based on ventricular morphology or severity of atrioventricular valve insufficiency. CONCLUSIONS: In this cohort of predominantly asymptomatic children and adolescents electively evaluated after a Fontan operation, all exhibited evidence for hepatic fibrosis as measured by collagen deposition in the liver. Time from Fontan was the only factor significantly associated with collagen deposition. These findings demonstrate that liver fibrosis is an inherent feature of Fontan physiology and that the degree of fibrosis increases over time.
Assuntos
Técnica de Fontan/efeitos adversos , Cardiopatias Congênitas/cirurgia , Hemodinâmica , Cirrose Hepática/etiologia , Fígado/patologia , Adolescente , Biópsia , Cateterismo Cardíaco , Colágeno/metabolismo , Estudos Transversais , Ecocardiografia , Feminino , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/fisiopatologia , Humanos , Fígado/metabolismo , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Cirrose Hepática/fisiopatologia , Masculino , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Adulto JovemRESUMO
OBJECTIVES: To determine the cardiovascular effects of obesity on patients with tetralogy of Fallot (TOF) repair. STUDY DESIGN: Ventricular performance measures were compared between obese (body mass index [BMI] ≥95%), overweight (85% ≤BMI <95%), and normal weight subjects (BMI <85%) in a retrospective review of patients with TOF who underwent cardiac magnetic resonance from 2005-2010. Significance was P < .05. RESULTS: Of 260 consecutive patients with TOF, 32 were obese (12.3%), 48 were overweight (18.5%), and 180 were normal weight (69.2%). Biventricular mass was increased in obese compared with normal weight patients with right ventricular mass more affected than left ventricular mass. Obese patients demonstrated decreased biventricular end-diastolic volume (EDV) and stroke volume (SV) when indexed to body surface area (BSA) with an increased heart rate when compared with normal weight patients; cardiac index, ejection fraction, and pulmonary regurgitation fraction were similar. When indexed to ideal BSA, biventricular EDV and SV were similar. EDV and SV for overweight patients were nearly identical to normal weight patients with ventricular mass in between the other 2 groups. CONCLUSIONS: Approximately 12% of patients after TOF repair referred for cardiac magnetic resonance in a tertiary referral center are obese with increased biventricular mass. Obese patients and normal weight patients have similar cardiac indices, however, when indexed to actual BSA, obese patients demonstrate decreased EDV and SV with increased heart rate and similar cardiac indices. When indexed to ideal BSA, no differences in biventricular volumes were noted.
Assuntos
Frequência Cardíaca/fisiologia , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Obesidade/complicações , Volume Sistólico/fisiologia , Tetralogia de Fallot/cirurgia , Adolescente , Índice de Massa Corporal , Criança , Pré-Escolar , Feminino , Humanos , Imagem Cinética por Ressonância Magnética , Masculino , Obesidade/epidemiologia , Obesidade/fisiopatologia , Prevalência , Estudos Retrospectivos , Tetralogia de Fallot/complicações , Tetralogia de Fallot/fisiopatologia , Função Ventricular/fisiologiaRESUMO
In Bi-directional Glenn (BDG) physiology, the superior systemic circulation and pulmonary circulation are in series. Consequently, only blood from the superior vena cava is oxygenated in the lungs. Oxygenated blood then travels to the ventricle where it is mixed with blood returning from the lower body. Therefore, incremental changes in oxygen extraction ratio (OER) could compromise exercise tolerance. In this study, the effect of exercise on the hemodynamic and ventricular performance of BDG physiology was investigated using clinical patient data as inputs for a lumped parameter model coupled with oxygenation equations. Changes in cardiac index, Qp/Qs, systemic pressure, oxygen extraction ratio and ventricular/vascular coupling ratio were calculated for three different exercise levels. The patient cohort (n=29) was sub-grouped by age and pulmonary vascular resistance (PVR) at rest. It was observed that the changes in exercise tolerance are significant in both comparisons, but most significant when sub-grouped by PVR at rest. Results showed that patients over 2 years old with high PVR are above or close to the upper tolerable limit of OER (0.32) at baseline. Patients with high PVR at rest had very poor exercise tolerance while patients with low PVR at rest could tolerate low exercise conditions. In general, ventricular function of SV patients is too poor to increase CI and fulfill exercise requirements. The presented mathematical model provides a framework to estimate the hemodynamic performance of BDG patients at different exercise levels according to patient specific data.
Assuntos
Exercício Físico/fisiologia , Hemodinâmica , Oxigênio/metabolismo , Circulação Pulmonar/fisiologia , Função Ventricular/fisiologia , Criança , Pré-Escolar , Tolerância ao Exercício/fisiologia , Cardiopatias Congênitas/fisiopatologia , Ventrículos do Coração/fisiopatologia , Humanos , Lactente , Recém-Nascido , Descanso/fisiologia , Resistência Vascular/fisiologia , Veia Cava Superior/fisiopatologiaRESUMO
The considerable blood mixing in the bidirectional Glenn (BDG) physiology further limits the capacity of the single working ventricle to pump enough oxygenated blood to the circulatory system. This condition is exacerbated under severe conditions such as physical activity or high altitude. In this study, the effect of high altitude exposure on hemodynamics and ventricular function of the BDG physiology is investigated. For this purpose, a mathematical approach based on a lumped parameter model was developed to model the BDG circulation. Catheterization data from 39 BDG patients at stabilized oxygen conditions was used to determine baseline flows and pressures for the model. The effect of high altitude exposure was modeled by increasing the pulmonary vascular resistance (PVR) and heart rate (HR) in increments up to 80% and 40%, respectively. The resulting differences in vascular flows, pressures and ventricular function parameters were analyzed. By simultaneously increasing PVR and HR, significant changes (p <0.05) were observed in cardiac index (11% increase at an 80% PVR and 40% HR increase) and pulmonary flow (26% decrease at an 80% PVR and 40% HR increase). Significant increase in mean systemic pressure (9%) was observed at 80% PVR (40% HR) increase. The results show that the poor ventricular function fails to overcome the increased preload and implied low oxygenation in BDG patients at higher altitudes, especially for those with high baseline PVRs. The presented mathematical model provides a framework to estimate the hemodynamic performance of BDG patients at different PVR increments.
Assuntos
Altitude , Cardiopatias Congênitas/fisiopatologia , Frequência Cardíaca , Resistência Vascular/fisiologia , Cateterismo Cardíaco , Pré-Escolar , Estudos de Coortes , Técnica de Fontan/métodos , Ventrículos do Coração/fisiopatologia , Hemodinâmica , Humanos , Lactente , Modelos Cardiovasculares , Oxigênio/químicaRESUMO
OBJECTIVE: To test the hypothesis that safety, efficacy, and image quality in pediatric patients who undergo deep sedation for cardiac magnetic resonance imaging (CMR) for congenital heart disease (CHD) is similar to general anesthesia (GA). STUDY DESIGN: Retrospective review of all CMR records from 1997-2006. Six hundred sixty patients underwent deep sedation (DS) and 161 underwent GA. Statistics included analysis of variance, chi(2) analysis, and the coefficient of variation. RESULTS: Diagnoses included a broad spectrum of CHD. No serious adverse events (AE) including mortalities and hospitalizations occurred because of DS. There were 18 (2.8%) self-limited events in the DS group with a success rate of 97.9%. The AE rate for patients undergoing GA was 3.9% (n = 6), including 2 overnight hospital stays with a success rate of 100%. AE and success rates did not differ between the 2 groups. Observers blinded to the patient's group found no difference in image quality. Even in young infants, excellent image quality was obtained. CONCLUSIONS: Sedation of appropriately screened pediatric patients with CHD undergoing CMR is safe and well tolerated and yields high-quality images similar to GA. GA should be considered for patients with CHD with hemodynamic or airway compromise, in whom sedation has failed, or who have special circumstances.