Comparison of echocardiographic and cardiac magnetic resonance imaging measurements of functional single ventricular volumes, mass, and ejection fraction (from the Pediatric Heart Network Fontan Cross-Sectional Study).

Assessment of the size and function of a functional single ventricle (FSV) is a key element in the management of patients after the Fontan procedure. Measurement variability of ventricular mass, volume, and ejection fraction (EF) among observers by echocardiography and cardiac magnetic resonance imaging (CMR) and their reproducibility among readers in these patients have not been described. From the 546 patients enrolled in the Pediatric Heart Network Fontan Cross-Sectional Study (mean age 11.9 +/- 3.4 years), 100 echocardiograms and 50 CMR studies were assessed for measurement reproducibility; 124 subjects with paired studies were selected for comparison between modalities. Interobserver agreement for qualitative grading of ventricular function by echocardiography was modest for left ventricular (LV) morphology (kappa = 0.42) and weak for right ventricular (RV) morphology (kappa = 0.12). For quantitative assessment, high intraclass correlation coefficients were found for echocardiographic interobserver agreement (LV 0.87 to 0.92, RV 0.82 to 0.85) of systolic and diastolic volumes, respectively. In contrast, intraclass correlation coefficients for LV and RV mass were moderate (LV 0.78, RV 0.72). The corresponding intraclass correlation coefficients by CMR were high (LV 0.96, RV 0.85). Volumes by echocardiography averaged 70% of CMR values. Interobserver reproducibility for the EF was similar for the 2 modalities. Although the absolute mean difference between modalities for the EF was small (<2%), 95% limits of agreement were wide. In conclusion, agreement between observers of qualitative FSV function by echocardiography is modest. Measurements of FSV volume by 2-dimensional echocardiography underestimate CMR measurements, but their reproducibility is high. Echocardiographic and CMR measurements of FSV EF demonstrate similar interobserver reproducibility, whereas measurements of FSV mass and LV diastolic volume are more reproducible by CMR.

Predictors of outcome of arterial switch operation for complex D-transposition.

BACKGROUND: Overall mortality and reoperation risk for the arterial switch operation (ASO) for D-transposition of the great arteries (D-TGA) is low. D-TGA with ventricular septal defect (VSD) and aortic arch obstruction (AAO) is a higher risk subgroup in which we sought risk factors for mortality and reoperation after ASO. METHODS: Echocardiograms of 74 patients who underwent ASO, VSD, and arch repair for D-TGA, VSD and AAO were reviewed; the reoperation analysis considered the 65 survivors. Pre-ASO clinical and anatomic characteristics were compared between survivors and nonsurvivors; patients who required (R) and did not require (NR) reoperation. RESULTS: Distal transverse aortic arch (TrAo) z score equal to -2.5 or less, triscuspid valve z score less than 0, repaired muscular VSD, and circulatory arrest time were significant predictors of mortality. When stratified for circulatory arrest time below 60 minutes, small distal transverse aortic arch and tricuspid valve remained significant predictors of mortality. Mean aortic annulus size was smaller in R than NR (p = 0.048). Left coronary artery arising posteriorly was associated with a reoperation hazard ratio of 5.2 (p = 0.022). CONCLUSIONS: Preoperative anatomy was associated with death and reoperation post-ASO. Small TrAo and TV were risk factors for mortality in univariate analysis, and remained significant in the subset of patients with short circulatory arrest times, suggesting that even when controlling for technical factors, anatomic risk factors predict mortality. Small aortic annulus and posterior left circumflex artery origin were associated with reoperation. Patients with D-TGA, VSD, and AAO constitute a higher risk group, which includes patients who may be marginal candidates for two-ventricle repair.

Cardiac changes associated with growth hormone therapy among children treated with anthracyclines.

OBJECTIVE: The objective was to assess the cardiac effects of growth hormone (GH) therapy. Anthracycline-treated childhood cancer survivors frequently have reduced left ventricular (LV) wall thickness and contractility, and GH therapy may affect these factors. METHODS: We examined serial cardiac findings for 34 anthracycline-treated childhood cancer survivors with several years of GH therapy and baseline cardiac z scores similar to those of a comparison group (86 similar cancer survivors without GH therapy). RESULTS: LV contractility was decreased among GH-treated patients before, during, and after GH therapy (-1.08 SD below the age-adjusted population mean before therapy and -1.88 SD 4 years after therapy ceased, with each value depressed below normal). Contractility was higher in the control group than in the GH-treated group, with this difference being nearly significant. The GH-treated children had thinner LV walls before GH therapy (-1.38 SD). Wall thickness increased during GH therapy (from -1.38 SD to -1.09 SD after 3 years of GH therapy), but the effect was lost shortly after GH therapy ended and thickness diminished over time (-1.50 SD at 1 year after therapy and -1.96 SD at 4 years). During GH therapy, the wall thickness for the GH-treated group was greater than that for the control group; however, by 4 years after therapy, there was no difference between the GH-treated group and the control group. CONCLUSIONS: GH therapy among anthracycline-treated survivors of childhood cancer increased LV wall thickness, but the effect was lost after therapy was discontinued. The therapy did not affect the progressive LV dysfunction.

Long-term predictors of aortic root dilation and aortic regurgitation after arterial switch operation.

BACKGROUND: Neo-aortic root dilation (ARD) and neo-aortic regurgitation (AR) may be progressive after arterial switch operation (ASO) for d-loop transposition of the great arteries (dTGA). We sought to identify predictors of ARD and AR after ASO. METHODS AND RESULTS: 335 patients were identified who underwent ASO for dTGA with intact ventricular septum or ventricular septal defect (VSD), including double-outlet right ventricle (DORV), before 2001 with at least 1 postoperative echocardiogram at our institution, at least 1 year after ASO, and no previous atrial switch procedure (median follow-up of 5.0 years). Probability of freedom from ARD was 97%, 92%, 82%, and 51%, from at least moderate AR was 98%, 97%, 96%, and 93%, and from neo-aortic valve or root surgery was 100%, 100%, 99%, and 95%, at 1, 2, 5, and 10 years, respectively. For patients in whom ARD developed, progressive dilation was not observed during late follow-up. By Kaplan-Meier method, independent predictors of ARD, with neo-aortic root z-score of > or =3.0, were previous pulmonary artery band (PAB) (P=0.002, hazard ratio [HR]=2.4) and later time period when ASO was performed (P<0.002, HR=19.0). Risk factor for at least moderate AR was age > or =1 year at ASO (P=0.002, HR=5.8), which was closely related to VSD repair at ASO (P<0.001) and previous PAB. CONCLUSIONS: Significant ARD and AR continue to develop over time after ASO, but ARD does not tend to be progressive during late follow-up. Previous PAB was a significant risk factor for ARD. Older age at time of ASO, presence of VSD, and previous PAB were risk factors for AR.

Familial restrictive cardiomyopathy with skeletal abnormalities.

A family is described in which 5 of 9 living children were found to have restrictive cardiomyopathy associated with skeletal muscle and orthopedic abnormalities. In the absence of another identifiable etiology, a genetic cause for restrictive cardiomyopathy in this family is probable. Consistent with the poor prognosis encountered for children with restrictive cardiomyopathy, 2 children in this family died, whereas a third was symptomatic by age 3 years.

Cardiac management by pediatricians versus pediatric cardiologists in an inpatient academic center.

BACKGROUND: Limited resources, managed care, and advances in technology have led to the suggestion that physicians other than cardiologists be further empowered to perform the initial cardiac evaluation in children with suspected heart disease. To study this strategy, we compared the management decisions of pediatricians with the recommendations of pediatric cardiologists who reviewed the records of the same patients. METHODS: Sixty-nine patients aged <23 years with suspected heart disease were referred by pediatricians (n = 40) on the inpatient service at Boston Medical Center for either a cardiology consultation or echocardiography. Two pediatric cardiologists who were blinded to the management decisions and clinical outcomes later reviewed the patient records. Recommendations between the 2 pediatric cardiologist reviewers and the managing pediatricians were compared. RESULTS: Pediatricians scheduled significantly fewer cardiology follow-up visits, instituted cardiac medications significantly less often, arranged significantly fewer family meetings to review cardiac findings, and ordered significantly fewer additional cardiac procedures than the pediatric cardiologists. This result was consistent regardless of whether the pediatrician's management decisions were made on the basis of the echocardiogram results only or on the recommendations of a cardiology consultant. The 2 pediatric cardiologist reviewers agreed more often with each other than either did with the managing pediatricians. CONCLUSIONS: Pediatricians have different management styles than pediatric cardiologists for patients with suspected cardiac disease. The effect of these differences on outcome is unknown, and further investigation is warranted.