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Background: Aortopulmonary collateral flow is considered to have significant impact on the outcome of patients with single ventricle circulation and total cavopulmonary connection (TCPC). There is little information on collateral flow during exercise., Purpose: To quantify aortopulmonary collateral flow at rest and during continuous submaximal exercise in clinical patients doing well with TCPC., Study Type: Prospective, case controlled., Population: Thirteen patients with TCPC (17 (11-37) years) and 13 age and sex-matched healthy controls (18 (11-38) years)., Field Strength: 1.5T; free breathing; phase sensitive gradient echo sequence., Assessment: Blood flow in the ascending and descending aorta and superior vena cava were measured at rest and during continuous submaximal physical exercise in patients and controls. Systemic blood flow (Q s ) was assumed to be represented by the sum of flow in the superior caval vein (Q svc ) and the descending aorta (Q AoD ) at the diaphragm level. Aortopulmonary collateral flow (Q coll ) was calculated by subtracting Q s from flow in the ascending aorta (Q AoA )., Statistics: Mann-Whitney U-test and Wilcoxon test for comparison between groups and between rest and exercise., Results: Absolute collateral flow in TCPC patients at rest was 0.4 l/min/m 2 (-0.1-1.2), corresponding to 14% (-2-42) of Q s . Collateral flow did not change during exercise (difference -0.01 (-0.7-1.0) l/min/m 2 , P = 0.97). TCPC patients had significantly lower Q s at rest (2.5 (1.6-4.1) vs. 3.5 (2.6-4.8) l/min/m 2 , P = 0.001) and during submaximal exercise (3.2 (2.0-6.0) vs. 4.8 (3.3-6.9) l/min/m 2 , P = 0.001), compared to healthy controls. The increase in Q s with exercise was also significantly lower in patients than in healthy controls (median 0.6 vs. 1.2 l/min/m 2 , P < 0.02)., Data Conclusion: Clinical patients doing well with TCPC have significant aortopulmonary collateral flow at rest (14% of Q s ) compared to healthy controls, which does not change during submaximal exercise., Level of Evidence: 2 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2018;47:1509-1516., (© 2017 International Society for Magnetic Resonance in Medicine.)

Aims: We compared flow and wall shear stress (WSS) patterns in the ascending aorta of individuals with either bicuspid aortic valve (BAV) or tricuspid aortic valve (TAV) using four-dimensional cardiovascular magnetic resonance (4D-CMR). BAV are known to be associated with dilation and dissection of the ascending aorta. However, the cause of vessel disease in patients with BAVs is unknown. Inborn connective tissue disease and also dilation secondary to increased WSS because of altered blood flow patterns in the ascending aorta are discussed as causes for dilation of the aorta. WSS can be estimated non-invasively by 4D-CMR., Methods and Results: Eighteen, otherwise, healthy individuals with functionally normal BAVs were compared prospectively with an age- and sex-matched control group of healthy individuals with TAV. Blood flow data were obtained by 4D-CMR visualization and WSS was calculated with specific software tools. Eighty-five per cent of the individuals with BAVs showed a high-grade helical flow pattern in the ascending aorta compared with 6% of the individuals with TAV. WSS in the ascending aorta was significantly altered in individuals with BAVs compared with TAV., Conclusion: WSS and flow patterns in the ascending aorta in patients with BAVs without concomitant valve or vessel disease are significantly different compared with TAV. The significantly higher shear forces may have an impact on the development of aortic dilation in patients with BAVs.

Background: To investigate aortic dimensions in women with Turner syndrome (TS) in relation to aortic valve morphology, blood pressure, karyotype, and clinical characteristics., Methods and Results: A cross sectional study of 102 women with TS (mean age 37.7; 18-62 years) examined by cardiovascular magnetic resonance (CMR- successful in 95), echocardiography, and 24-hour ambulatory blood pressure. Aortic diameters were measured by CMR at 8 positions along the thoracic aorta. Twenty-four healthy females were recruited as controls. In TS, aortic dilatation was present at one or more positions in 22 (23%). Aortic diameter in women with TS and bicuspid aortic valve was significantly larger than in TS with tricuspid valves in both the ascending (32.4 +/- 6.7 vs. 26.0 +/- 4.4 mm; p < 0.001) and descending (21.4 +/- 3.5 vs. 18.8 +/- 2.4 mm; p < 0.001) aorta. Aortic diameter correlated to age (R = 0.2 - 0.5; p < 0.01), blood pressure (R = 0.4; p < 0.05), a history of coarctation (R = 0.3; p = 0.01) and bicuspid aortic valve (R = 0.2-0.5; p < 0.05). Body surface area only correlated with descending aortic diameter (R = 0.23; p = 0.024)., Conclusions: Aortic dilatation was present in 23% of adult TS women, where aortic valve morphology, age and blood pressure were major determinants of the aortic diameter.

Background: Patients after atrial switch operation for transposition of the great arteries have limited exercise performance. Rigid atrial baffles may cause a relative preload reduction. Previous studies have had suboptimal control groups, which ideally should consist of patients with congenitally corrected transposition of the great arteries (ccTGA) without previous heart surgery, having a systemic right ventricle, but lacking rigid atrial baffles. Therefore the aim of this study was to test the impact of atrial baffles by comparing 12 atrial switch patients with 11 ccTGA patients., Methods and Results: Systemic right ventricular stroke volume (SV), heart rate, cardiac index, and other parameters were assessed during rest and dobutamine stress magnetic resonance imaging. The most important difference between the groups was that the atrial switch patients could not increase SV during stress, whereas ccTGA patients increased it significantly. There was no difference between groups in the rise of the cardiac index. Heart rate increased significantly more in atrial switch patients than in ccTGA patients., Conclusions: The results support the hypothesis that atrial baffles restrict a rise in SV under dobutamine stress in patients after atrial switch operation for transposition of the great arteries.

Objectives: To compare images of the aorta obtained with helical CT (HCT) scanning and MRI for the follow-up of adults with coarctation of the aorta (CoA). Design: Longitudinal study. Setting: Department of adult congenital heart disease in a tertiary university hospital. Patients: A total of 37 adults (age range, 16 to 68 years; women, 13) with CoA (after surgery, 34 patients; native, 2 patients; after balloon-angioplasty, 1 patient) Measurements and results: All patients underwent both HCT and MRI of the thoracic aorta within a mean (± SD) time interval of 1.86 ± 1.11 years. Aortic diameters measured at six intrathoracic levels showed a high correlation (r = 0.79 to 0.94). On average, slightly lower diameters were measured with MRI (1.2 mm). But there was a substantial variation between the two measurements with differences of up to 9 mm. All other pathomorphologic abnormalities were detected and classified similarly with both methods. Conclusions: HCT and MRI are similarly useful for the noninvasive evaluation of the thoracic aorta in patients with CoA. But there can be a substantial variation in two subsequent measurements without an overall substantial bias toward larger diameter in one of the two methods. In repetitive studies, changes of the diameters should be interpreted with care, especially when assessing the progression of aortic diameters. [ABSTRACT FROM AUTHOR]

Abstract: Background: Clinical, hemodynamic and functional effects of tricuspid valve surgery in patients with Ebstein''s anomaly are not well understood. Methods: Sixteen patients (median age of 27.7years) were examined before and eight months after surgery by means of echocardiography, cardiovascular magnetic resonance (CMR) and cardiopulmonary exercise testing. Results: Peak work load (1.87 to 2.0W/kg; p=0.026), maximum oxygen uptake (21 to 22ml/kg/min; p=0.034) as well as cardiac output (2.7 to 2.9l/min/m2; p=0.035) increased postoperatively. The reduction of tricuspid regurgitation led to a higher pulmonary stroke volume (29 to 42ml/m2, p=0.005) and augmented the left ventricular (LV) volume (55 to 63ml/min/m2; p=0.001) with a trend to better ejection fraction (61 to 64%; p=0.083). Right ventricular (RV) volume index (124 to 108ml/m2; p=0.034) and ejection fraction (50 to 42%; p=0.036) decreased on CMR. Echocardiographic measurements of RV function also decreased (tricuspid annular plane systolic excursion 2.3 to 1.7; p=0.002; isovolumic acceleration 0.98 to 0.65; p=0.004; and 2-d longitudinal global strain −19.3 to −16.25; p=0.006). Conclusion: Tricuspid valve surgery improves exercise capacity in patients with Ebstein''s anomaly. The reduction of tricuspid regurgitation decreases the volume of the right ventricle and increases pulmonary antegrade flow. As a result LV volume and cardiac output increase. This hemodynamic benefit occurs despite the preload dependent reduction in RV volume and ejection fraction. [Copyright &y& Elsevier]