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Background: In adults with prior arterial switch operation (ASO) for d-transposition of the great arteries, the need for routine coronary artery assessment and evaluation for silent myocardial ischemia is not well defined. In this observational study we aimed to determine the value of a comprehensive cardiovascular magnetic resonance (CMR) protocol for the detection of coronary problems in adults with prior ASO for d-transposition of the great arteries., Methods: Adult ASO patients (≥18 years of age) were recruited consecutively. Patients underwent a comprehensive stress perfusion CMR protocol that included measurement of biventricular systolic function, myocardial scar burden, coronary ostial assessment and myocardial perfusion during vasodilator stress by perfusion CMR. Single photon emission computed tomography (SPECT) was performed on the same day as a confirmatory second imaging modality. Stress studies were visually assessed for perfusion defects (qualitative analysis). Additionally, myocardial blood flow was quantitatively analysed from mid-ventricular perfusion CMR images. In unclear cases, CT coronary angiography or conventional angiography was done., Results: Twenty-seven adult ASO patients (mean age 23 years, 85% male, 67% with a usual coronary pattern; none with a prior coronary artery complication) were included in the study. CMR stress perfusion was normal in all 27 patients with no evidence of inducible perfusion defects. In 24 cases the coronary ostia could conclusively be demonstrated to be normal. There was disagreement between CMR and SPECT for visually-assessed perfusion defects in 54% of patients with most disagreement due to false positive SPECT., Conclusions: Adult ASO survivors in this study had no CMR evidence of myocardial ischemia, scar or coronary ostial abnormality. Compared to SPECT, CMR provides additional valuable information about the coronary artery anatomy. The data shows that the asymptomatic and clinically stable adult ASO patient has a low pre-test probability for inducible ischemia. In this situation it is likely that routine evaluation with stress CMR is unnecessary.

Background: The utility of cardiac magnetic resonance imaging (CMR) for assessment of adults with Ebstein anomaly is not well-defined. We sought to evaluate CMR characteristics in this population and to relate these to exercise parameters., Methods: We analyzed CMR studies in adults with unrepaired Ebstein anomaly for measures of severity of Ebstein disease, including atrialized, functional and total right ventricular (RV) volumes, ejection fraction (EF) and severity index (area of atrialized RV+right atrium/functional RV+left ventricle+left atrium). We related these CMR values to cardiopulmonary exercise test measurements., Results: Twenty-seven adults (mean age 41 ± 14 years, 70% female) were included. Functional RV end-diastolic volume (EDV) was 150 ± 68 mL/m(2) and atrialized RVEDV was 25 ± 24 mL/m(2). In 17 patients (63%), the functional RVEDV was enlarged (>114 mL/m(2)). Percent predicted peak VO2 for the population was 65 ± 20%. On univariable analysis, peak VO2 was inversely related to atrialized RVEDV (p = 0.011), total RVEDV (p = 0.041), functional RVEDV/left ventricular EDV ratio (p = 0.015) and magnitude of tricuspid valve displacement (p = 0.031). In the multivariate model, the only CMR factor to relate to peak VO2 was atrialized RVEDV (p = 0.011, β = -0.48). No significant correlations were found between CMR measures and heart rate response or ventilatory response to exercise., Conclusion: In adults with unrepaired Ebstein anomaly, atrialized RV volume was independently related to aerobic capacity. The volume of the atrialized RV is a novel CMR measure which may express severity of disease. Further research is needed to evaluate the prognostic relevance of this exploratory work., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Background: The aim of this study was to develop a mathematical model using two-dimensional echocardiographic parameters to estimate right ventricular end-diastolic volume (RVEDVi) in adults with repaired tetralogy of Fallot., Methods: Linear regression equations were used to examine the relationship between two-dimensional echocardiographic and cardiac magnetic resonance (CMR) imaging measures of RVEDVi. Imaging studies in 101 adults were used to create and validate the model. The ability of the model to detect changes in CMR RVEDVi was tested in 57 adults with serial studies., Results: The optimal model to quantitate CMR RVEDVi included two-dimensional echocardiographic right ventricular end-diastolic area measured in the apical four-chamber view, indexed to body surface area (AreaDi) (CMR RVEDVi = 11.5 + [7 x AreaDi]). The model reliably allowed the detection of stable and changing CMR RVEDVi (kappa = 0.84 and kappa = 0.82, respectively, P < .0001)., Conclusion: Quantitative assessment of right-ventricular volumes by echocardiography is feasible and may be used for serial follow-up in patients with contraindications for CMR., (2010 American Society of Echocardiography. Published by Mosby, Inc. All rights reserved.)

Abstract: Background: Adverse ventricular-ventricular interactions have been recognized in those with repaired tetralogy of Fallot (TOF) and severe pulmonary regurgitation. Objective: We aimed to examine the impact of pulmonary valve replacement (PVR) on the left heart late after TOF repair. Methods and results: Left ventricular (LV) volumes and ejection fractions (EF) were analyzed in adults with severe pulmonary regurgitation after TOF repair with cardiac magnetic resonance imaging (CMR) before and after PVR. Thirty-nine patients (median age 33[20–65] years) were reviewed. Post-PVR, LVEF improved significantly in the entire cohort (50±9%→54±7%, p<0.001) and in those with moderately impaired (defined as LVEF ≤45%) preoperative LVEF (38±5%→47±6%, p<0.0001), but was not statistically different in those with relatively preserved (defined as LVEF >45%) preoperative LVEF. By multivariate linear regression analysis to evaluate independent CMR predictors of improved LVEF post-PVR for the entire cohort, the only CMR variable to emerge was preoperative LVEF (p=0.012, regression coefficient −0.54, SE 0.13). Whereas PVR resulted in increased LV filling in patients with relatively preserved preoperative LVEF reflected by an increase in LV end-diastolic volumes (77±10→82±16mL/m2, p=0.05), LV end-systolic volumes decreased after PVR in patients with impaired preoperative LVEF (65±12→54±10mL/m2, p=0.001) but LV end-diastolic volumes were not significantly changed. Conclusion: When LVEF is decreased after TOF repair, PVR appears to have a salutary effect on postoperative LVEF, thereby supporting the concept of recovery of adverse right–left heart interactions. Mechanisms of left heart improvement post-PVR differ depending on degree of preoperative LV systolic dysfunction. [Copyright &y& Elsevier]

Abstract: Background: The right ventricular (RV) systolic function is important for decision making in adults with repaired tetralogy of Fallot (rTOF). Our aim was to assess regional RV systolic function and its impact on global RV systolic function by echocardiography. Methods: In 101 adults with rTOF, regional RV systolic function on echocardiography was compared to 50 individuals with structurally normal hearts. In patients with rTOF, the impact of echocardiographic measures of regional RV systolic function on global RV-ejection fraction as measured by cardiac magnetic resonance imaging (CMR-RVEF) was determined. Results: Compared to normals, patients with rTOF had impaired systolic function of the RV outflow tract. Patients with rTOF and normal CMR-RVEF compensate this loss of RV outflow tract function with increased contractions of the RV-body, measured as fractional area change on short axis (30±12% versus 19±7%, p<0.0001) and on 4-chamber views (42±7% versus 38±8%, p=0.06). In contrast, patients with rTOF and abnormal global CMR-RVEF showed significantly lower systolic function of the RV-body compared to normal controls (fractional area change on 4-chamber view: 31±6% versus 38±8%, p<0.0001). A simple regression model, incorporating fractional shortening of RV outflow tract and fractional area change on 4-chamber view allows accurate echocardiographic estimation of the CMR-derived RVEF. Conclusions: Patients with repaired tetralogy of Fallot have markedly different regional systolic RV-function compared to normals, even when the global RV systolic function is preserved. The systolic function of the RV outflow tract and of the RV body are both important determinants of global systolic RV function in these patients. Their prognostic significance needs to be determined. [Copyright &y& Elsevier]