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Purpose: To evaluate trans-left atrioventricular valve (LAVV) blood flow and optimize left ventricular inflow quantification in healthy controls and patients after atrioventricular septal defect (AVSD) correction., Materials and Methods: Twenty-five patients after AVSD correction and 25 controls underwent 4DFlow MRI. Using streamline visualization in four- and two-chamber views, inflow direction at early and late filling was defined at the annulus level and at the peak inflow velocity (PIV) level. Trans-LAVV flow volume and velocity were assessed from a static 2D-multiplanar-reformat (MPR), a 4D-MPR tracking LAVV annulus and a 4D-MPR tracking the PIV-level, angulated perpendicular to the inflow., Results: In patients, on average 9° more laterally directed inflow was found at the PIV-level compared to controls. In controls, 4DFlow velocity mapping with LAVV annulus tracking resulted in lower absolute error with aortic flow (3 (1-8) mL) than with static 2D-MPR (7 (4-16) mL, P = 0.001). In patients, 4D-MPR tracking the PIV-level, resulted in lower absolute error with aortic flow (2 (1-4) mL) than with 4D-MPR LAVV annulus tracking (6 (2-10) mL, P = 0.003)., Conclusion: Streamline visualization of 4DFlow MRI data revealed dynamic trans-LAVV inflow and more lateral flow after AVSD correction. Streamline visualization improved trans-LAVV flow quantification as the positioning and angulation of the measurement plane was optimized, allowing an accurate assessment of left ventricular inflow., (© 2014 Wiley Periodicals, Inc.)

Purpose: To evaluate the effect of spatial (ie, number of sampling locations along the aorta) and temporal sampling density on aortic pulse wave velocity (PWV) assessment from velocity-encoded MRI in patients with Marfan syndrome (MFS)., Materials and Methods: Twenty-three MFS patients (12 men, mean age 36 ± 14 years) were included. Three PWV-methods were evaluated: 1) reference PWV(i.p.) from in-plane velocity-encoded MRI with dense temporal and spatial sampling; 2) conventional PWV(t.p.) from through-plane velocity-encoded MRI with dense temporal but sparse spatial sampling at three aortic locations; 3) EPI-accelerated PWV(t.p.) with sparse temporal but improved spatial sampling at five aortic locations with acceleration by echo-planar imaging (EPI)., Results: Despite inferior temporal resolution, EPI-accelerated PWV(t.p.) showed stronger correlation (r = 0.92 vs. r = 0.65, P = 0.03) with reference PWV(i.p.) in the total aorta, with less error (8% vs. 16%) and variation (11% vs. 27%) as compared to conventional PWV(t.p.) . In the aortic arch, correlation was comparable for both EPI-accelerated and conventional PWV(t.p.) with reference PWV(i.p.) (r = 0.66 vs. r = 0.67, P = 0.46), albeit 92% scan-time reduction by EPI-acceleration., Conclusion: Improving spatial sampling density by adding two acquisition planes along the aorta results in more accurate PWV assessment, even when temporal resolution decreases. For regional PWV assessment in the aortic arch, EPI-accelerated and conventional PWV assessment are comparably accurate. Scan-time reduction makes EPI-accelerated PWV assessment the preferred method of choice., (Copyright © 2012 Wiley Periodicals, Inc.)

The survival of patients with congenital heart disease (CHD) has greatly improved over the past decades. Nevertheless, lifelong follow-up is required in postoperative CHD patients, and noninvasive imaging plays an important role during follow-up. Cardiac MR (CMR) imaging enables comprehensive imaging of cardiac function and anatomy, and helps to detect patients who need re-intervention and to predict clinical outcome. Postoperative CHD patients who are frequently referred for CMR evaluation include those with coarctation of the aorta, tetralogy of Fallot, transposition of the great arteries, and single ventricle patients after the Fontan procedure. This article reviews the current clinical role of CMR in these various subgroups of postoperative CHD patients. Furthermore, an overview of novel CMR applications and their clinical value in CHD patients is provided., (Copyright © 2012 Wiley Periodicals, Inc.)

Purpose: To study age-related change in aortic stiffness in patients with Marfan syndrome (MFS) versus healthy volunteers using velocity-encoded (VE) MRI., Materials and Methods: Twenty-five MFS patients (age range, 18-63 years; mean age 36 ± 14 years, 13 men) and 25 age-/gender-matched healthy volunteers were examined with VE-MRI. Aortic stiffness was expressed by pulse wave velocity (PWV), assessed in the proximal and distal part of the aorta and in the total aorta. PWV was compared between patients and volunteers and age-relation was determined by linear regression., Results: PWV was significantly higher in all parts of the aorta in patients when compared with healthy volunteers (proximal aorta 5.7 ± 1.5 m/s versus 4.8 ± 0.9 m/s, distal aorta 6.4 ± 2.4 m/s versus 5.0 ± 1.2 m/s and total aorta 5.9 ± 1.7 m/s versus 4.9 ± 1.1 m/s, all P < 0.004). PWV correlated significantly with age (Pearson R between 0.45 and 0.94). Only in the proximal aorta, the increase in PWV with age was significantly higher in patients (7 ± 2 cm/s increase with age) than in volunteers (3 ± 1 cm/s increase, P = 0.03); in the distal or total aorta, the increase in PWV with age was not different between patients and volunteers., Conclusion: Velocity-encoded MRI detects more pronounced age-related aortic stiffening in the proximal aorta in MFS patients versus healthy volunteers, suggesting more severe wall disease in MFS., (Copyright © 2011 Wiley-Liss, Inc.)

Multislice computed tomography (MSCT) provides high accuracy for noninvasive assessment of coronary artery disease (CAD). The introduction of the latest computed tomography (CT) technology allows comprehensive evaluation of various aspects of CAD, including the coronary calcium score, coronary artery stenoses, bypass patency, and myocardial function. Other applications, such as plaque characterization, first-pass perfusion imaging, and viability imaging using delayed contrast enhancement, are still under development and may demonstrate clinical utility in the future. Further improvements in CT hardware and imaging protocols are expected that may result in improved coronary artery imaging, new applications, and a significant reduction of radiation dose., (Copyright 2007 Wiley-Liss, Inc.)

The distribution and elimination of contrast agents is mainly determined by their size. First-pass perfusion with the use of blood pool contrast agents (BPCAs) and/or rapid clearance blood-pool-like contrast agents may allow quantitative myocardial perfusion evaluation in patients. This requires contrast bolus injection with a very fast injection speed. A major profit from BPCAs is expected for magnetic resonance angiography (MRA). The persistent signal-enhancing effects of BPCAs allow for a longer acquisition time window, which may be used to increase both the signal-to-noise ratio and/or image resolution. This is of paramount importance for coronary imaging, in which high-resolution imaging is desired. Moreover, the improved acquisition time window can be used to make multiple scans after one contrast injection. The role of ultrasmall paramagnetic iron oxide particles (USPIOs) for MRA is not clear yet, as they are limited by T2* effects at higher doses. Several safety aspects have to be taken into account before BPCAs are applied in humans, for whom toxicity caused by the injection speed is a concern.

The purpose of this study was to assess the ability of the new blood pool contrast agent meglumine-carboxymethyldextran-ethylenediamino-gadoterate (CMD-A2-Gd-DOTA) to depict acute occlusive myocardial infarction (AMI). First-pass gradient-echo and delayed spin-echo magnetic resonance imaging (MRI) was performed 5 days after induction of AMI in a pig model. MRI was correlated with pathology. First-pass imaging with CMD-A2-Gd-DOTA allowed detection of infarcted myocardium in all pigs (n = 7). The infarction was recognized as a black spot on MRI as well as on a parametric image. The signal intensity (SI) amplitudes of normal versus infarcted myocardium were 80.55 +/- 18.61 versus 8.48 +/- 15.50 on MRI and 81.62 +/- 18.50 versus 1.61 +/- 3.73 on the parametric image (both P values < 0.001. The contrast ratio between normal and infarcted myocardium was not significantly improved on spin-echo MRI, suggesting largely intact vascular integrity outside the occluded area. CMD-A2-Gd-DOTA is useful for depicting occlusive myocardial infarction by first-pass MRI. Spin-echo imaging is promising in assessing vascular integrity. J. Magn. Reson. Imaging 1999;10:170-177., (Copyright 1999 Wiley-Liss, Inc.)

Meglumine-carboxymethyldextran-ethylenediamino-gadoterate (CMD-A2-Gd-DOTA) was evaluated as a blood pool contrast agent for magnetic resonance angiography (MRA). MRA of large body vasculature was performed in seven pigs using a gradient-echo sequence at 1.5 T before and after 0.05 mmol/kg CMD-A2-Gd-DOTA injection. The signal- and contrast-to-noise ratios (SNRs, CNRs) were measured, as well as the pharmacokinetic clearance pattern. CMD-A2-Gd-DOTA visualized the vasculature with a high SNR and CNR for over 110 minutes after injection, but for the renal arteries the CNR was only significant within 15 minutes. Image quality was maximum within 15 minutes, producing enhancement (mean +/- SD) as follows: aortic arch 738 +/- 272%, abdominal aorta 393 +/- 123%, left renal artery 202 +/- 95%, right renal artery 248 +/- 107%, inferior vena cava 371 +/- 129%, and portal vein 513 +/- 145%, all P values < or =0.001. The clearance pattern was triphasic. Due to the excellent enhancement of vasculature without background enhancement, CMD-A2-Gd-DOTA is potentially a useful MR blood pool contrast agent for equilibrium phase MRA.