To examine feasibility and reproducibility and to evaluate the cardiovascular response to an isometric handgrip exercise in low-risk pediatric population using Cardiovascular Magnetic Resonance... Show moreTo examine feasibility and reproducibility and to evaluate the cardiovascular response to an isometric handgrip exercise in low-risk pediatric population using Cardiovascular Magnetic Resonance measurements. In a subgroup of 207 children with a mean age of 16 years participating in a population-based prospective cohort study, children performed an isometric handgrip exercise. During rest and exercise, continuous heart rate and blood pressure were measured. Cardiovascular magnetic resonance (CMR) measurements included left ventricular mass, aortic distensibility and pulse wave velocity at rest and left ventricular end-diastolic and end-systolic volumes, ejection fraction, stroke volume and cardiac output during rest and exercise. 207 children had successful CMR measurements in rest and 184 during exercise. We observed good reproducibility for all cardiac measurements. Heart rate increased with a mean ± standard deviation of 42.6% ± 20.0 and blood pressure with 6.4% ± 7.0, 5.4% ± 6.1 and 11.0% ± 8.3 for systolic, diastolic and mean arterial blood pressure respectively (p-values < 0.05). During exercise, left ventricular end-diastolic and end-systolic volumes and cardiac output increased, whereas left ventricular ejection fraction slightly decreased (p-values < 0.05). Stroke volume did not change significantly. A sustained handgrip exercise of 7 min at 30–40% maximal voluntary contraction is a feasible exercise-test during CMR in a healthy pediatric population, which leads to significant changes in heart rate, blood pressure and functional measurements of the left ventricle in response to exercise. This approach offers great novel opportunities to detect subtle differences in cardiovascular health. Show less
Background: Aortic root dilatation is common in adults with repaired tetralogy of Fallot (rTOF) and might lead to aortic dissection. However, little is known on progression of aortic dilatation and... Show moreBackground: Aortic root dilatation is common in adults with repaired tetralogy of Fallot (rTOF) and might lead to aortic dissection. However, little is known on progression of aortic dilatation and the effect of pharmaceutical treatment. This study aims to determine factors associated with aortic growth and investigate effects of losartan.Methods and results: We performed a prespedfied analysis from the 1:1 randomized, double-blind REDEFINE trial. Aortic root diameters were measured at baseline and after 2.0 = 0.3 years of follow-up using cardiovascular magnetic resonance (CMR) imaging. A total of 66 patients were included (68% men, age 40 +/- 12 years, baseline aortic root 37 +/- 6 mm, 32% aortic dilatation (>40 mm)). There was a trend towards slow aortic root growth (+0.6 +/- 2.3 mm after two years, p = 0.06) (n = 60). LV stroke volume was the only factor associated with both a larger baseline aortic root (beta: 0.09 mm/ml (95% C.I.:0.02, 0.15), p - 0.010) and with aortic growth during follow-up (beta: 0.04 rim/rill (95% C.L:0.005, 0.066), p = 0.024), after correction for age, sex, and body surface area using linear regression analysis. No treatment effect of losartan was found (p = 0.17).Conclusions: Aortic root dilatation was present in about one-third of rTOF patients. A larger LV stroke volume was associated with both a larger baseline aortic root and ongoing growth. Our findings provide no arguments for lower aortic diameter thresholds for prophylactic surgery compared to the general population. (C) 2020 Elsevier B.V. All rights reserved. Show less
Minderhoud, S.C.S.; Velde, N. van der; Wentzel, J.J.; Geest, R.J. van der; Attrach, M.; Wielopolski, P.A.; ... ; Hirsch, A. 2020
Background Cardiovascular magnetic resonance (CMR) phase contrast (PC) flow measurements suffer from phase offset errors. Background subtraction based on stationary phantom measurements can most... Show moreBackground Cardiovascular magnetic resonance (CMR) phase contrast (PC) flow measurements suffer from phase offset errors. Background subtraction based on stationary phantom measurements can most reliably be used to overcome this inaccuracy. Stationary tissue correction is an alternative and does not require additional phantom scanning. The aim of this study was 1) to compare measurements with and without stationary tissue correction to phantom corrected measurements on different GE Healthcare CMR scanners using different software packages and 2) to evaluate the clinical implications of these methods. Methods CMR PC imaging of both the aortic and pulmonary artery flow was performed in patients on three different 1.5 T CMR scanners (GE Healthcare) using identical scan parameters. Uncorrected, first, second and third order stationary tissue corrected flow measurement were compared to phantom corrected flow measurements, our reference method, using Medis QFlow, Circle cvi42 and MASS software. The optimal (optimized) stationary tissue order was determined per scanner and software program. Velocity offsets, net flow, clinically significant difference (deviation > 10% net flow), and regurgitation severity were assessed. Results Data from 175 patients (28 (17-38) years) were included, of which 84% had congenital heart disease. First, second and third order and optimized stationary tissue correction did not improve the velocity offsets and net flow measurements. Uncorrected measurements resulted in the least clinically significant differences in net flow compared to phantom corrected data. Optimized stationary tissue correction per scanner and software program resulted in net flow differences (> 10%) in 19% (MASS) and 30% (Circle cvi42) of all measurements compared to 18% (MASS) and 23% (Circle cvi42) with no correction. Compared to phantom correction, regurgitation reclassification was the least common using uncorrected data. One CMR scanner performed worse and significant net flow differences of > 10% were present both with and without stationary tissue correction in more than 30% of all measurements. Conclusion Phase offset errors had a significant impact on net flow quantification, regurgitation assessment and varied greatly between CMR scanners. Background phase correction using stationary tissue correction worsened accuracy compared to no correction on three GE Healthcare CMR scanners. Therefore, careful assessment of phase offset errors at each individual scanner is essential to determine whether routine use of phantom correction is necessary. Show less
Gassenmaier, S.; Geest, R.J. van der; Schoepf, U.J.; Suranyi, P.; Rehwald, W.G.; Cecco, C.N. de; ... ; Varga-Szemes, A. 2018
