Christian Luecke

Diagnostic Performance of CMR Imaging Compared With EMB in Patients With Suspected Myocarditis

OBJECTIVES The goal of this study was to assess the diagnostic performance of cardiac magnetic resonance (CMR) compared with endomyocardial biopsy in patients with suspected acute myocarditis (AMC) and chronic myocarditis (CMC). BACKGROUND Several studies have reported an encouraging diagnostic performance of CMR in myocarditis. However, the comparison of CMR with clinical data only and the use of preselected patient populations are important limitations of the majority of these reports. METHODS One hundred thirty-two consecutive patients with suspected AMC (defined by symptoms ≤ 14 days; n = 70) and CMC (defined by symptoms >14 days; n = 62) were included. Patients underwent cardiac catheterization with left ventricular endomyocardial biopsy and CMR, including T(2)-weighted imaging for assessment of edema, T(1)-weighted imaging before and after contrast administration for evaluation of hyperemia, and assessment of late gadolinium enhancement. CMR results were considered to be consistent with the diagnosis of myocarditis if 2 of 3 CMR techniques were positive. RESULTS Within the total population, myocarditis was the most common diagnosis on endomyocardial biopsy analysis (62.9%). Viral genomes were detected in 30.3% (40 of 132) of patients within the total patient population and significantly more often in patients with AMC than CMC (40.0% vs. 19.4%; p = 0.013). For the overall cohort of patients with either suspected AMC or CMC, the diagnostic sensitivity, specificity, and accuracy of CMR were 76%, 54%, and 68%, respectively. The best diagnostic performance was observed in patients with suspected AMC (sensitivity, 81%; specificity, 71%; and accuracy, 79%). In contrast, diagnostic performance of CMR in suspected CMC was found to be unsatisfactory (sensitivity, 63%; specificity, 40%; and accuracy, 52%). CONCLUSIONS The results of this study underline the usefulness of CMR in patients with suspected AMC. In contrast, the diagnostic performance of CMR in patients with suspected CMC might not be sufficient to guide clinical management.

Comprehensive Cardiac Magnetic Resonance Imaging in Patients With Suspected Myocarditis: The MyoRacer-Trial.

BACKGROUND Data suggest that T1 and T2 mapping have excellent diagnostic accuracy in patients with suspected myocarditis. However, the true diagnostic performance of comprehensive cardiac magnetic resonance (CMR) mapping versus endomyocardial biopsy (EMB) has not been determined. OBJECTIVES This study assessed the performance of CMR imaging, including T1 and T2 mapping, compared with EMB in an unselected, consecutive patient cohort with suspected myocarditis. It also examined the potential role of CMR field strength by comparing 1.5-T versus 3.0-T imaging. METHODS Patients underwent biventricular EMB, cardiac catheterization (for exclusion of coronary artery disease), and CMR imaging on 1.5- and 3-T scanners. The CMR protocol included current standard Lake Louise criteria (LLC) for myocarditis as well as native T1, calculation of extracellular volume fraction (ECV), and T2 mapping (only on 1.5-T). Patients were divided into 2 groups according to symptom duration (acute: ≤14 days vs. chronic: >14 days). RESULTS A total of 129 patients underwent 1.5-T imaging. In patients with acute symptoms, native T1 yielded the best diagnostic performance as defined by the area under the curve (AUC) of receiver-operating curves (0.82) followed by T2 (0.81), ECV (0.75), and LLC (0.56). In patients with chronic symptoms, only T2 mapping yielded an acceptable AUC (0.77). On 3.0-T, AUCs of native T1, ECV, and LLC were comparable to 1.5-T with no significant differences. CONCLUSIONS In patients with acute symptoms, mapping techniques provide a useful tool for confirming or rejecting the diagnosis of myocarditis and are superior to the LLC. However, only T2 mapping has acceptable diagnostic performance in patients with chronic symptoms. (Magnetic Resonance Imaging in Myocarditis [MyoRacer]; NCT02177630).

Incidence, characteristics and functional implications of cerebral embolic lesions after the MitraClip procedure

AIMS This study aimed to assess the incidence and impact of cerebral embolic events after the MitraClip procedure. METHODS AND RESULTS Twenty-seven high-risk patients (logistic EuroSCORE I 25±15%) underwent the MitraClip procedure and cerebral diffusion-weighted magnetic resonance imaging (MRI) in median two days before and three days after the procedure. On the same day, neurocognitive function was assessed using the Montreal Cognitive Assessment (MoCA) questionnaire and thorough clinical examination. Comparison of pre- and post-interventional MRI showed that 23 of 27 patients (85.7%) had newly acquired microembolic lesions with in median three (interquartile range 1-9) new lesions per patient. Of these, three patients (11.1%) had lesions with diameter >5 mm. Patients with >3 new cerebral embolic lesions (n=13, 48%) had a lower post-interventional MoCA score in comparison to patients with ≤3 embolic lesions (23.6±3.6 vs. 20.3±4.5; p=0.046) in univariate analysis. Multivariate stepwise regression analysis identified device time as an independent predictor of the number of post-procedural new lesions (p=0.003) and, for reduced post-interventional MoCA score, a low MoCA score at baseline (p<0.001). CONCLUSIONS The MitraClip procedure results in new ischaemic cerebral lesions in the vast majority of patients. Preliminary data suggest that these lesions are clinically without significant impact on global cognitive function. ClinicalTrials.gov: NCT01288976.

The potential additional diagnostic value of assessing for pericardial effusion on cardiac magnetic resonance imaging in patients with suspected myocarditis

BACKGROUND The presence of pericardial effusion (PE) is considered to be suggestive of inflammation in suspected myocarditis. However, the incremental value of assessing for PE in addition to comprehensive cardiac magnetic resonance (CMR) imaging remains unclear. METHODS In total, 132 patients with suspected acute (AMC) or chronic myocarditis (CMC) were included. All patients underwent endomyocardial biopsy (EMB) and CMR. Imaging protocols included T2 imaging for the assessment of myocardial oedema (oedema ratio [ER]), T1 imaging before and after contrast agent administration for global relative enhancement (gRE) calculation, and late enhancement (LE). Furthermore, the presence and extent of PE were determined. The potential incremental diagnostic value of PE was determined by applying a two, three, or four out of four criteria approach including ER, gRE, LE, and PE. RESULTS PE was present in 84 of the 132 patients (63.6%) and was more common in suspected AMC vs. CMC (56 of 70 vs. 28 of 62; P < 0.001). According to EMB results, PE was found in 86% of patients with AMC, 67% with chronic myocarditis, and 56% without evidence of myocardial inflammation. Implementing PE into a three out of four approach did not result in improved accuracy compared with the established two out of three approach using ER, gRE, and LE (59 vs. 68% for the total population, 69 vs. 79% for suspected AMC, and 48 vs. 52% for suspected CMC). CONCLUSION The finding of PE in unselected patients with suspected AMC or CMC is not specific to myocarditis. Therefore, with the currently applied criteria and methods, assessment of PE does not improve the diagnostic performance of CMR in this patient cohort.

The systemic right ventricle in congenitally corrected transposition of the great arteries is different from the right ventricle in dextro-transposition after atrial switch: a cardiac magnetic resonance study.

BACKGROUND Patients with a congenitally corrected transposition of the great arteries show an increasing incidence of cardiac failure with age. In other systemic right ventricles, such as in dextro-transposition after atrial switch, excessive hypertrophy is a potential risk factor for impaired systolic function. In this trial, we sought to compare systemic function and volumes between patients with congenitally corrected transposition and those with dextro-transposition after atrial switch by using cardiac magnetic resonance imaging. METHODS AND RESULTS A total of 19 patients (nine male) with congenitally corrected transposition and 31 patients (21 male) with dextro-transposition after atrial switch were studied using a 1.5-Tesla scanner. Cine steady-state free-precession sequences in standard orientations were acquired for volumetric and functional imaging. Patient parameters were compared with those of a group of 25 healthy volunteers. Although patients with congenitally corrected transposition were older, they presented with higher right ventricular ejection fractions (p = 0.04) compared with patients with dextro-transposition. Patients with congenitally corrected transposition showed a weak negative correlation between age at examination and systemic ejection fraction (r = −0.18, p = 0.04) but no correlation between right ventricular myocardial mass index and ejection fraction. There was no significant difference in the right ventricular end-diastolic volumes between both patient groups. CONCLUSION Although patients with congenitally corrected transposition had a longer pressure load of the systemic right ventricle, ventricular function was better compared with that in patients with dextro-transposition after atrial switch. The results suggest that the systemic ventricles might have partly different physiologies. One difference could be the post-operative situation after atrial switch, which results in impaired atrial contribution to ventricular filling.

2071 Perioperative monitoring of microembolic cerebral events in patients undergoing different types of aortic valve replacement by magnet resonance imaging

Methods We examined 24 patients (20 female, 4 male) at an average age of 82 years suffering from an aortic valve stenosis before (mean = 3 days) and after (mean = 8 days) different types of AVR by Magnet Resonance Imaging (MRI) using a Philips Intera 1.5 T system. We acquired FLAIR-, T2and diffusion weighted transversal images with the following parameters: TR = 10000; 5000; 6230 ms, TE = 140; 100; 73 ms, FOV: 230–250 mm, matrix = 205*256; 307*512; 90*256. Different types of AVR were surgical AVR via sternotomy (3 patients), microinvasive transapical (11 patients), as well as transfemoral catheter based AVR (10 patients). New lesions between the two examinations were counted by two observers in consensus. Results The sequences using diffusion weighted imaging (DWI) detected most of the new embolic lesions (90) in 14 patients (58%). While with the post-operative FLAIR images only 37 new lesions in 13 patients (54%), with the T2-weighted images only 14 new lesions in 10 (41%) patients were identified. Figure 1 shows an example of positve findings in the different sequences.

Impact of heart rate and rhythm on radiation exposure in prospectively ECG triggered computed tomography

PURPOSE To evaluate the influence of different heart rates and arrhythmias on scanner performance, image acquisition and applied radiation exposure in prospectively ECG triggered computed tomography (pCT). MATERIALS AND METHODS An ECG simulator (EKG Phantom 320, Müller & Sebastiani Elektronik GmbH, Munich, Germany) was used to generate different heart rhythms and arrhythmias: sinus rhythm (SR) at 45, 60, 75, 90 and 120/min, supraventricular arrhythmias (e.g. sinus arrhythmia, atrial fibrillation) and ventricular arrhythmias (e.g. ventricular extrasystoles), pacemaker-ECGs, ST-changes and technical artifacts. The analysis of the image acquisition process was performed on a 64-row multidetector CT (Brilliance, Philips Medical Systems, Cleveland, USA). A prospectively triggered scan protocol as used for routine was applied (120 kV; 150 mAs; 0.4s rotation and exposure time per scan; image acquisition predominantly in end-diastole at 75% R-R-interval, in arrythmias with a mean heart rate above 80/min in systole at 45% of the R-R-interval; FOV 25 cm). The mean dose length product (DLP) and its percentage increase from baseline (SR at 60/min) were determined. RESULT Radiation exposure can increase significantly when the heart rhythm deviates from sinus rhythm. ECG-changes leading to a significant DLP increase (p<0.05) were bifocal pacemaker (61%), pacemaker dysfunction (22%), SVES (20%), ventricular salvo (20%), and atrial fibrillation (14%). Significantly (p<0.05) prolonged scan time (>8 s) could be observed in bifocal pacemaker (12.8 s), pacemaker dysfunction (10.7 s), atrial fibrillation (10.3 s) and sinus arrhythmia (9.3 s). CONCLUSION In prospectively ECG triggered CT, heart rate and rhythm can provoke different types of scanner performance, which can significantly alter radiation exposure and scan time. These results might have an important implication for indication, informed consent and contrast agent injection protocols.

Interobserver variability of myocardial T1 and T2 mapping in patients with suspected myocarditis

Background The aim of this study was to test the interobserver variability of myocardial T1 and T2 Mapping prior to and T1 Mapping after the administration of contrast agent in patients with suspected myocarditis. The established methods for the detection of the presence of active inflammation - edema ratio (ER) and global relative enhancement (gRE) - require a “normal” reference region of interest (ROI) in adjacent skeletal muscle and depend on the choice of the muscle as well as its outline

Cardiac MRI Texture Analysis of T1 and T2 Maps in Patients with Infarctlike Acute Myocarditis

Purpose To assess the diagnostic potential of texture analysis applied to T1 and T2 maps obtained with cardiac MRI for the diagnosis of acute infarctlike myocarditis. Materials and Methods This prospective study from August 2012 to May 2015 included 39 participants (overall mean age ± standard deviation, 34.7 years ± 12.2 [range, 18-63 years]; mean age of women, 46.1 years ± 10.8 [range, 24-63 years]; mean age of men, 29.8 years ± 9.2 [range, 18-56 years]) from the Magnetic Resonance Imaging in Myocarditis (MyoRacer) trial with clinical suspicion of acute myocarditis and infarctlike presentation. Participants underwent biventricular endomyocardial biopsy, cardiac catheterization, and cardiac MRI at 1.5 T, in which native T1 and T2 mapping as well as Lake Louise criteria (LLC) were assessed. Texture analysis was applied on T1 and T2 maps by using a freely available software package. Stepwise dimension reduction and texture feature selection was performed for selecting features enabling the diagnosis of myocarditis by using endomyocardial biopsy as the reference standard. Results Endomyocardial biopsy confirmed the diagnosis of acute myocarditis in 26 patients, whereas 13 participants had no signs of acute inflammation. Mean T1 and T2 values and LLC showed a low diagnostic performance, with area under the curve in receiver operating curve analyses as follows: 0.65 (95% confidence interval [CI]: 0.45, 0.85) for T1, 0.67 (95% CI: 0.49, 0.85) for T2, and 0.62 (95% CI: 0.42, 0.79) for LLC. Combining the texture features T2 run-length nonuniformity and gray-level nonuniformity resulted in higher diagnostic performance with an area under the curve of 0.88 (95% CI: 0.73, 1.00) (P < .001) and a sensitivity and specificity of 89% [95% CI: 81%, 93%] and 92% [95% CI: 77%, 93%], respectively. Conclusion Texture analysis of T2 maps shows high sensitivity and specificity for the diagnosis of acute infarctlike myocarditis.

Deutsche Kardiodiagnostiktage (DKDT) 2017 in Leipzig: Bildgebung im aktuellen Fokus

Die 9. Deutschen Kardiodiagnostiktage haben vom 23.–25. Februar wieder in Leipzig stattgefunden. Mit fast 600 Teilnehmern gehören die Deutschen Kardiodiagnostiktage mittlerweile zu den führenden kardiovaskulären Bildgebungssymposien in Europa und werden interdisziplinär unter der Ägide der Arbeitsgruppen für CT und MRT der Deutschen Gesellschaft für Kardiologie – Herzund Kreislaufforschung e. V. (DGK) und der AG Herzund Gefäßdiagnostik der Deutschen Röntgengesellschaft e. V. (DRG) organisiert. Ebenso erhält die Veranstaltung die aktive Unterstützung der AG Nuklearkardiologie der Deutschen Gesellschaft für Nuklearmedizin e. V. (DGN). An 3 Tagen wurden Entwicklungen, Trends und aktuelle Studienergebnisse auf dem Gebiet der kardiovaskulären Bildgebung diskutiert.