Alexander Berger

A bi-center cardiovascular magnetic resonance prognosis study focusing on dobutamine wall motion and late gadolinium enhancement in 3,138 consecutive patients.

To the Editor:nnIn the present study we sought to investigate the predictive value of resting and inducible wall motion abnormalities (WMA) and of late gadolinium enhancement (LGE) for hard cardiac outcomes and for revascularization procedures in 3,138 patients undergoing dobutamine cardiac magnetic

Delayed contrast-enhanced MRI of the coronary artery wall in takayasu arteritis.

Background Takayasu arteritis (TA) is a rare form of chronic inflammatory granulomatous arteritis of the aorta and its major branches. Late gadolinium enhancement (LGE) with magnetic resonance imaging (MRI) has demonstrated its value for the detection of vessel wall alterations in TA. The aim of this study was to assess LGE of the coronary artery wall in patients with TA compared to patients with stable CAD. Methods We enrolled 9 patients (8 female, average age 46±13 years) with proven TA. In the CAD group 9 patients participated (8 male, average age 65±10 years). Studies were performed on a commercial 3T whole-body MR imaging system (Achieva; Philips, Best, The Netherlands) using a 3D inversion prepared navigator gated spoiled gradient-echo sequence, which was repeated 34–45 minutes after low-dose gadolinium administration. Results No coronary vessel wall enhancement was observed prior to contrast in either group. Post contrast, coronary LGE on IR scans was detected in 28 of 50 segments (56%) seen on T2-Prep scans in TA and in 25 of 57 segments (44%) in CAD patients. LGE quantitative assessment of coronary artery vessel wall CNR post contrast revealed no significant differences between the two groups (CNR in TA: 6.0±2.4 and 7.3±2.5 in CAD; pu200a=u200a0.474). Conclusion Our findings suggest that LGE of the coronary artery wall seems to be common in patients with TA and similarly pronounced as in CAD patients. The observed coronary LGE seems to be rather unspecific, and differentiation between coronary vessel wall fibrosis and inflammation still remains unclear.

Value of additional strain analysis with feature tracking in dobutamine stress cardiovascular magnetic resonance for detecting coronary artery disease

BackgroundDobutamine stress cardiovascular magnetic resonance (DS-CMR) has been established for the detection of coronary artery disease (CAD). The novel technique feature tracking (FT) analyses left ventricular circumferential strain (Ecc) thus offering detailed information about myocardial deformation. The purpose of this study was to evaluate FT based Ecc for the detection of myocardial ischemia during DS-CMR.MethodsA total of 25 patients (18 males; mean age 64 ± 10 years) with suspected or known CAD underwent a standardized high-dose DS-CMR protocol at 1.5 T. For FT analysis cine short axis (SAX) views (apical, medial, basal) at rest and during maximum dobutamine stress were used. None of the patients had wall motion abnormalities (WMAs) or impaired left ventricular function at rest or scar tissue. For analysis of Ecc the three SAX planes were divided into 16 segments (n = 400 segments). During stress 15 patients (34 segments) developed WMAs as assessed by visual analysis. All patients underwent x-ray coronary angiography for clinical reasons which served as the reference standard. Patients without WMAs during DS-CMR and exclusion of stenotic CAD were defined as normal (10 patients, 160 segments). In patients with significant CAD segments that were supplied by a vessel of >70% narrowing were defined as stenotic (n = 64). The remaining segments in patients with significant CAD were considered as remote (n = 176).ResultsAt rest no differences in Ecc were observed between normal, stenotic and remote segments. High-dose dobutamine stress revealed highly significant differences between Ecc of normal and stenotic segments (p < 0.001), as well as between remote and stenotic segments (p < 0.001). The same observation took place for the absolute change of Ecc (p < 0.001 and p = 0.01). ROC analysis of Ecc during maximum DS-CMR differentiated normal from stenotic segments with a sensitivity of 75% and specificity of 67% using a cutoff -33.2% with an area under the curve of 0.78. Additional analysis of intermediate-dose dobutamine also showed a significant difference between normal and stenotic segments (p = 0.001).ConclusionFT based analysis of Ecc during intermediate- and high-dose DS-CMR was feasible and differentiated between stenotic, remote and normal segments. Quantitative assessment of Ecc with FT may improve the diagnostic accuracy of DS-CMR for detection of ischemia.

Endomyocardial fibrosis in patients with confirmed Churg–Strauss syndrome

term safety and efficacy of tocilizumab, an anti-IL-6 receptor monoclonal antibody, in monotherapy, in patients with rheumatoid arthritis (the STREAM study): evidence of safety and efficacy in a 5-year extension study. Ann Rheum Dis 2009;68:1580 4. 33 Dougados M, Kissel K, Sheeran T et al. Adding tocilizumab or switching to tocilizumab monotherapy in methotrexate inadequate responders: 24-week symptomatic and structural results of a 2-year randomised controlled strategy trial in rheumatoid arthritis (ACT-RAY). Ann Rheum Dis 2012;72:43 50.

Value of strain analysis with feature tracking in adenosine stress myocardial perfusion magnetic resonance imaging

Background Adenosine stress magnetic resonance is highly accurate for the detection of myocardial perfusion abnormalities. Visual assessment of inducible wall motion abnormalities (IWMA) during adenosine has low sensitivity but high specificity since only high-grade perfusion defects are associated with detectable IWMAs. The novel technique Feature Tracking (FT) measures myocardial strain and gives detailed information about regional myocardial deformation. The aim of this study was to investigate FT for the detection of myocardial ischemia during adenosine stress.

Comparison of myocardial tagging and feature tracking in patients with severe aortic stenosis.

BACKGROUND AND AIM OF THE STUDYnTranscatheter aortic valve implantation (TAVI) has become an effective treatment for severe aortic stenosis (AS) in patients considered to be at high surgical risk. However, data relating to myocardial function and deformation in these patients are rare. Cardiovascular magnetic resonance (CMR) tagging has been established as non-invasive technique for the accurate measurement of myocardial motion. However, additional tagging datasets are necessary and the post-processing procedure is time-consuming. Recently, the novel technique of feature tracking (FT) was introduced, with which myocardial strain can be derived directly from balanced steady-state free precession (bSSFP) cine sequences. The study aim was to compare tagging with FT in patients with high-grade AS and who had been considered for TAVI.nnnMETHODSnThirty patients with severe AS underwent cardiac magnetic resonance imaging at 1.5 T (Philips Achieva). A stack of serial short-axis slices was used to assess left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), and LV mass and function. TomTec 2D Cardiac Performance Analysis software was used to derive myocardial deformation parameters from three short-axis cine views (basal, medial and apical levels) using bSSFP. All patients also underwent myocardial tagging on identical short-axis views, and data acquired from FT and tagging were compared.nnnRESULTSnThe mean left ventricular ejection fraction (LVEF), LVEDV and LVESV (57 ± 14%, 158 ± 58 ml, and 74 ± 48 ml, respectively) were all normal. All patients demonstrated concentric hypertrophy of the left ventricle with an increased basal septal thickness (16 ± 3 mm), LV mass (126 ± 40 g) and indexed LV mass (68 ± 23 g/m2, papillary muscles excluded). Bland-Altman analysis revealed a reasonable agreement between basal and medial circumferential strain (cc), and a good correlation was observed between tagging and FT for the derived basal and medial cc (Pearsons correlation coefficient 0.83 for basal, 0.74 for medial). Basal rotation was impaired compared to previous studies in patients with AS, but medial and apical rotations were comparable. The apical peak diastolic rotation velocity was faster compared to earlier analyses. Rotation, peak systolic and end-diastolic rotation velocity did not demonstrate any correlation or acceptable agreement between FT and tagging. The inter-observer agreement as assessed by the intra- class correlation coefficient for FT showed good results for the cc (basal 0.94, medial 0.83, apical 0.75).nnnCONCLUSIONnTo the present authors knowledge, this is the first study to assess myocardial motion using tagging and FT in patients with AS prior to TAVI. A reasonable agreement was found for the basal and medial cc between both techniques. Estimated cc-values using FT were systematically higher than those with tagging, but this might have been due to the different techniques employed. Although FT is a promising method to assess cc, further studies including the evaluation of standard values--and investigations with different diseases are necessary.

Non-invasive quantification of anatomical and functional renal artery vessel wall changes in patients with resistant hypertension undergoing renal denervation using MRI

Background Renal Denervation (RDN) is a novel therapy for patients with resistant hypertension. Its direct effects on the renal arteries in humans are poorly examined. We sought to assess renal artery distensibility noninvasively using magnetic resonance imaging (MRI) and to study the effects of RDN on anatomical and functional changes of the renal artery vessel wall. Methods 19 patients with resistant hypertension undergoing RDN were prospectively included. A 3.0T MRI including contrast-enhanced renal artery angiography was performed before the RDN procedure and at 6-month follow-up. In each patient the proximal part of both renal arteries was imaged for the cross-sectional area measurements using cine spiral MRI. Renal artery sharpness was evaluated with a quantitative analysis tool (Soap-Bubble Tool). In a subgroup of 11 patients, the distensibility (mm Hg(-1) × 10(3)) was determined as (maximum lumen area minimal lumen area)/(pulse pressure × minimal lumen area). The pulse pressure was calculated as the difference between the systolic and diastolic brachial blood pressure. Results Renal artery sharpness values before and 6 months after RDN did not differ significantly (49.15 ± 7.11 vs 47.43 ± 8.5, respectively, p = 0.255). Similarly, renal artery distensibility was not significantly different before RDN

Quantification of diffuse myocardial fibrosis in patients with resistant hypertension undergoing renal denervation versus hypertensive controls - preliminary results

Background Renal Denervation (RDN) is a novel therapy for patients with resistant hypertension. Its cardiac effects at followup are currently unknown. On the other hand, T1 mapping permits the assessment of myocardial extracellular volume (ECV), a parameter proposed to quantify diffuse myocardial fibrosis and independently associated with mortality and hard cardiovascular events. Our aim was to study the effects of RDN on ECV at 6-month follow-up. Methods 14 patients with resistant hypertension undergoing RD (RD group) and 4 resistant hypertensive patients not undergoing RD (control group) were prospectively included. A 1.5T cardiac MR including T1 mapping preand post-contrast was performed before the RD procedure and at 6-month follow-up in both groups. Blood hematocrit was determined at both time points. Images were post-processed using commercial software (Qmass, Medis

Comprehensive characterization of cardiac morphology and function in adult patients with phenylketonuria using CMR

Background Phenylketonuria (PKU) is one of the most common inherited metabolic disorders. The molecular pathway of neurological damage is not yet sufficiently understood. To date, there is a lack information about cardiac involvement related to the disease. This study aims to characterize cardiac morphology and function in adult patients with PKU using cardiovascular magnetic resonance (CMR).

Value of strain analysis with feature tracking in dobutamine stress cardiac magnetic resonance imaging for detecting coronary artery disease

Background Dobutamine stress magnetic resonance (DSMR) has been established for the detection of coronary artery disease (CAD) due to its high diagnostic accuracy and prognostic value. The novel technique feature tracking (FT) analyses regional myocardial strain and thereby offers detailed information about myocardial deformation. The purpose of this study was to examine how FT based circumferential strain (CS) compares to visually detected wall motion abnormalities (WMA) during DSMR and whether it adds beneficial information for detecting CAD. Methods A total of 25 patients (72% male; mean age 64 ± 8) with suspected or known CAD underwent a standardized high-dose DSMR protocol at 1.5 T. CMR images were acquired at rest and during stress in three short-axis views (SAX; apical, medial, basal). None of the patients had evidence for WMAs or impaired left ventricular function at rest or scar tissue based on late gadolinium enhancement (LGE). For strain analysis the SAX planes were divided into 16 segments (n = 400 segments). All patients underwent x-ray coronary angiography for clinical reasons. Patients without WMA during DSMR and exclusion of CAD by coronary angiography were defined as normal and served as control (10 patients, 160 segments). 15 patients developed WMA during DSMR (34 segments). Additionally, based on angiographic findings, segments that were supplied by a vessel with >75% were defined as stenotic (64 segments). The remaining segments, which did not develop a WMA or were supplied by a vessel <50% narrowing, were considered as remote segments (161 segments). Results At rest no differences in CS were observed between groups (normal: -28.1 ± 8.9; WMA: -24.8 ± 12.9; stenotic: 25.8 ± 10.6; remote: 27.7 ± 11.7%; p = 0.23). High dose dobutamine stress revealed highly significant differences between normal segments and segments with WMA (normal: -39.3 ± 11.3%; WMA: 19.2 ± 19.1%; p < 0.001) as well as between normal and stenotic and normal and remote segments (stenotic: -23.8 ± 15.9%, p < 0.001; remote: -34.2 ± 14.1%, p < 0.001). Additionally, analysis of the absolute change in CS between rest and stress showed significant differences for normal segments vs. segments with WMA (Δ normal: -11.2 ± 12.6%, Δ WMA: 5.6 ± 22.9%; p = 0.001), as well as between normal and stenotic segments (Δ stenotic: 1.9 ± 18.4%; p < 0.001) and between normal and remote segments (Δ remote: -6.6 ± 16.3%; p = 0.027). CS results are summarized in Figure 1. ROC analysis of CS during maximum DSMR differentiated normal from stenotic segments with a sensitivity of 75% and specificity of 67% using a cutoff -33.2% with an area under the curve of 0.78 (Figure 2). Conclusions FT based CS analysis demonstrated significant differences between normal segments and segments with WMA in DSMR. Additionally, FT detected significantly impaired CS in stenotic segments compared to normal segments. FT based CS may improve the diagnostic accuracy of DSMR for detection of ischemia.