Effects of Levosimendan on cardiac function, size and strain in heart failure patients.

Levosimendan improves cardiac function in heart failure populations; however, its exact mechanism is not well defined. We analysed the short-term impact of levosimendan in heart failure patients with ischemic and non-ischemic cardiomyopathy (CMP) using multiparametric cardiac magnetic resonance (CMR). We identified 33 patients with ischemic or non-ischemic CMP who received two consecutive CMR scans prior to and within one week after levosimendan administration. Changes in LV ejection fraction (LVEF) and LV volumes, as well as changes in strain rates, were measured prior to and within one week after levosimendan infusion. LV scarring, based on late gadolinium enhancement (LGE), was correlated to changes in LV size and strain rates. Both LV endiastolic (EDV) and endsystolic volumes (ESV) significantly decreased (EDV: p=0,001; ESV: p=0,002) after levosimendan administration, with no significant impact on LVEF (p=0.41), cardiac output (p=0.61), and strain rates. Subgroup analyses of ischemic or non-ischemic CMP showed no significant differences between the groups in terms of short-term LV reverse remodeling. The presence and extent of scarring in LGE did not correlate with changes in LV size and strain rates. CMR is able to monitor cardiac effects of levosimendan infusion. Short-term follow-up of a single levosimendan infusion using CMR shows a significant decrease in LV size, but no impact on LVEF or strain measurements. There was no difference between patients with ischemic or non-ischemic CMP. Quantification of LV scarring in CMR is not able to predict changes in LV size and strain rates in response to levosimendan.

Endoleak detection using single-acquisition split-bolus dual-energy computer tomography (DECT).

OBJECTIVES: To assess a single-phase, dual-energy computed tomography (DECT) with a split-bolus technique and reconstruction of virtual non-enhanced images for the detection of endoleaks after endovascular aneurysm repair (EVAR). METHODS: Fifty patients referred for routine follow-up post-EVAR CT and a history of at least one post-EVAR follow-up CT examination using our standard biphasic (arterial and venous phase) routine protocol (which was used as the reference standard) were included in this prospective trial. An in-patient comparison and an analysis of the split-bolus protocol and the previously used double-phase protocol were performed with regard to differences in diagnostic accuracy, radiation dose, and image quality. RESULTS: The analysis showed a significant reduction of radiation dose of up to 42 %, using the single-acquisition split-bolus protocol, while maintaining a comparable diagnostic accuracy (primary endoleak detection rate of 96 %). Image quality between the two protocols was comparable and only slightly inferior for the split-bolus scan (2.5 vs. 2.4). CONCLUSIONS: Using the single-acquisition, split-bolus approach allows for a significant dose reduction while maintaining high image quality, resulting in effective endoleak identification. KEY POINTS: • A single-acquisition, split-bolus approach allows for a significant dose reduction. • Endoleak development is the most common complication after endovascular aortic repair (EVAR). • CT angiography is the imaging modality of choice for aortic aneurysm evaluation.

[Functional MR imaging of the liver]. / Funktionelle MR-Tomographie der Leber.

The diagnostics of diffuse liver disease traditionally rely on liver biopsies and histopathological analysis of tissue specimens. However, a liver biopsy is invasive and carries some non-negligible risks, especially for patients with decreased liver function and those requiring repeated follow-up examinations. Over the last decades, magnetic resonance imaging (MRI) has developed into a valuable tool for the non-invasive characterization of focal liver lesions and diseases of the bile ducts. Recently, several MRI methods have been developed and clinically evaluated that also allow the diagnostics and staging of diffuse liver diseases, e.g. non-alcoholic fatty liver disease, hepatitis, hepatic fibrosis, liver cirrhosis, hemochromatosis and hemosiderosis. The sequelae of diffuse liver diseases, such as a decreased liver functional reserve or portal hypertension, can also be detected and quantified by modern MRI methods. This article provides the reader with the basic principles of functional MRI of the liver and discusses the importance in a clinical context.

Stent graft surface movement after infrarenal abdominal aortic aneurysm repair: comparison of patients with and without a type 2 endoleak.

OBJECTIVES: The aim was to compare multidirectional stent graft movement in patients with and without a type 2 endoleak. METHODS: This was a retrospective case control study of patients being followed up after elective endovascular aneurysm repair of abdominal aortic aneurysms. The post-procedural and final follow up multislice computed tomography (MSCT) of 69 patients with and 74 without a type 2 endoleak were analyzed. Three dimensional (3D) surface models of the stent graft, delimited by landmarks using custom built software, were derived from these MSCT data. The stent graft was segmented in different zones, and the proportion of the total stent graft surface moving >9 mm between the post-procedural and the final follow up MSCT was calculated, given in percentages, and compared between groups. Changes of infrarenal neck, renal artery to stent graft distance, and freedom from stent graft related endoleaks were evaluated. RESULTS: Overall surface movement was higher in the no endoleak (18.8%, IQR 0.1-45.1%) than in the type 2 endoleak group (5.3%, IQR 0-29.7%; p = .06). Furthermore, significantly higher surface movement in the no endoleak group was found in the proximal anchoring zone (p = .04) and the distal left limb (p = .01), which was the modular limb in 81.1% (p < .01). Neck diameter increase (1.0 mm, IQR 0-3.0 mm; p < .01) and renal artery to stent graft distance difference (0 mm, IQR 0-3.3 mm; p < .01) were significantly higher in the no endoleak group. Five patients in the no endoleak and one patient in the type 2 endoleak group suffered from a stent graft related endoleak (p = .27). CONCLUSIONS: The presence of a type 2 endoleak is associated with decreased surface movement of the proximal anchoring zone and the distal modular limb of bifurcated stent grafts.

Diagnostic workup of primary sclerosing cholangitis: the benefit of adding gadoxetic acid-enhanced T1-weighted magnetic resonance cholangiography to conventional T2-weighted magnetic resonance cholangiography.

AIM: To evaluate the value of gadoxetic acid-enhanced T1-weighted (T1W) magnetic resonance cholangiography (MRC) versus conventional T2-weighted (T2W) MRC compared to endoscopic retrograde cholangiopancreatography (ERCP) in patients with primary sclerosing cholangitis (PSC). MATERIALS AND METHODS: Based on T1W MRC, PSC patients were classified into a regular (RG) and a delayed (DG) excreting group, with an absence of gadoxetic acid in the common bile duct at 20 min. Beading, pruning, and gradation of central bile duct stenosis, evaluated by T1W and T2W MRC, were compared to ERCP. Liver parenchymal enhancement was measured in both study groups and compared to a reference group (n = 20) without a history of liver disease. Two readers performed all measurements. RESULTS: Based on beading and pruning of the peripheral bile ducts, sensitivities, specificities, and accuracies for reader 1 were 0.17/0.43, 0/0.17, and 0.15/0.31 for T1W MRC, and 0.83/0.86, 1/0.83, and 0.85/0.85 for T2W MRC (p = 0.004). For reader 2 sensitivities, specificities, and accuracies were 0.25/0.57, 0/0.33, and 0.23/0.46 for T1W MRC, and 0.92/1, 1/0.83, and 0.92/0.92 for T2W MRC (p = 0.012). Compared to ERCP, central bile duct stenoses were significantly overestimated (p < 0.001) by T2W MRC. A significantly lower parenchymal enhancement was found in the DG (n = 7) compared to the RG (n = 13), and compared to the reference group (p < 0.001). CONCLUSION: The combined performance of T2W and T1W MRC may provide a comprehensive imaging workup of PSC, including morphological and functional information resulting in optimal management.