Robert Manka

Inselspital, Universitätsspital Bern, Berna, Bern, Switzerland

Are you Robert Manka?

Claim your profile

Publications (81)485.21 Total impact

  • International journal of cardiology 01/2016; 202:62-63. DOI:10.1016/j.ijcard.2015.08.165 · 4.04 Impact Factor
  • Sandra Hamada · Frank Enseleit · Robert Manka
    The international journal of cardiovascular imaging 09/2015; DOI:10.1007/s10554-015-0765-0 · 1.81 Impact Factor
  • Circulation 08/2015; 132(6-6):e38-e40. DOI:10.1161/circulationaha.115.017284 · 14.43 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Left ventricular thrombus (LVT) formation may worsen the post-infarct outcome as a result of thromboembolic events. It also complicates the use of modern antiplatelet regimens, which are not compatible with long-term oral anticoagulation. The knowledge of the incidence of LVT may therefore be of importance to guide antiplatelet and antithrombotic therapy after acute myocardial infarction (AMI). In 177 patients with large, mainly anterior AMI, standard cardiac magnetic resonance imaging (CMR) including cine and late gadolinium enhancement (LGE) imaging was performed shortly after AMI as per protocol. CMR images were analysed at an independent core laboratory blinded to the clinical data. Transthoracic echocardiography (TTE) was not mandatory for the trial, but was performed in 64% of the cases following standard of care. In a logistic model, 3 out of 61 parameters were used in a multivariable model to predict LVT. LVT was detected by use of CMR in 6.2% (95% confidence interval [CI] 3.1%-10.8%). LGE sequences were best to detect LVT, which may be missed in cine sequences. We identified body mass index (odds ratio 1.18; p = 0.01), baseline platelet count (odds ratio 1.01, p = 0.01) and infarct size as assessed by use of CMR (odds ratio 1.03, p = 0.02) as best predictors for LVT. The agreement between TTE and CMR for the detection of LVT is substantial (kappa = 0.70). In the current analysis, the incidence of LVT shortly after AMI is relatively low, even in a patient population at high risk. An optimal modality for LVT detection is LGE-CMR but TTE has an acceptable accuracy when LGE-CMR is not available.
    Schweizerische medizinische Wochenschrift 06/2015; 145:w14122. DOI:10.4414/smw.2015.14122 · 2.09 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Purpose To evaluate the potential of advanced modeled iterative reconstruction (ADMIRE) for optimizing radiation dose of high-pitch coronary CT angiography (CCTA). Methods High-pitch 192-slice dual-source CCTA was performed in 25 patients (group 1) according to standard settings (ref. 100 kVp, ref. 270 mAs/rot). Images were reconstructed with filtered back projection (FBP) and ADMIRE (strength levels 1–5). In another 25 patients (group 2), high-pitch CCTA protocol parameters were adapted according to results from group 1 (ref. 160 mAs/rot), and images were reconstructed with ADMIRE level 4. In ten patients of group 1, vessel sharpness using full width at half maximum (FWHM) analysis was determined. Image quality was assessed by two independent, blinded readers. Results Interobserver agreements for attenuation and noise were excellent (r = 0.88/0.85, p p p Conclusions In a selected population, ADMIRE can be used for optimizing high-pitch CCTA to an effective dose of 0.3 mSv. Key points • Advanced modeled IR (ADMIRE) reduces image noise up to 50 % as compared to FBP. • Coronary artery vessel borders show an increasing sharpness at higher ADMIRE levels. • High-pitch CCTA with ADMIRE is possible at a radiation dose of 0.3 mSv.
    European Radiology 06/2015; DOI:10.1007/s00330-015-3862-5 · 4.01 Impact Factor
  • European Heart Journal 04/2015; DOI:10.1093/eurheartj/ehv147 · 15.20 Impact Factor
  • Circulation Cardiovascular Imaging 03/2015; 8(5). DOI:10.1161/CIRCIMAGING.114 · 5.32 Impact Factor
  • European Heart Journal 02/2015; 36(16). DOI:10.1093/eurheartj/ehv020 · 15.20 Impact Factor
  • Source
    Journal of Cardiovascular Magnetic Resonance 02/2015; 17(1). DOI:10.1186/1532-429X-17-S1-P88 · 4.56 Impact Factor
  • M Niemann · H Alkadhi · A Gotschy · S Kozerke · R Manka
    [Show abstract] [Hide abstract]
    ABSTRACT: Since the discovery of the obese (ob) gene product leptin, fat has been considered an endocrine organ. Especially epicardial fat has gained increasing attention in recent years. The epicardial fat plays a major role in fat metabolism; however, harmful properties have also been reported. Echocardiography, computed tomography and cardiac magnetic resonance imaging are the non-invasive tools used to measure epicardial fat volume. This review briefly introduces the basic physiological and pathophysiological considerations concerning epicardial fat. The main issue of this review is the presentation of non-invasive measurement techniques of epicardial fat using various imaging modalities and a literature overview of associations between epicardial fat and common cardiovascular diseases.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Over the past decade, cardiovascular magnetic resonance (CMR) has become an established non-invasive imaging modality in cardiology. It provides clinicians and researchers with an unparalleled versatility of diagnostic parameters such as cardiac morphology, function, myocardial texture and vascular flow. One of the most relevant applications of CMR is the assessment of patients with suspected or known coronary artery disease (CAD). In large clinical trials, CMR has proven its robustness, diagnostic performance and prognostic value in CAD. In patients with known or suspected chronic CAD, detection of ischaemia and myocardial viability for guiding therapeutic decisions is a major strength of CMR. Patients with ischaemic congestive heart failure (CHF) may benefit from CMR for planning of device implantation or monitoring intracavital thrombi. Finally, the use of CMR in the emergency department for the assessment of patients with acute chest pain is an emerging field, in which CMR's capability to characterize myocardial tissue regarding e.g. necrosis, edema or microvascular obstruction (MVO) may prove clinically useful. The CMR technology is safe, free of ionizing radiation and proved higher diagnostic accuracy and superior cost efficiency compared with other standard diagnostic modalities. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
    International Journal of Cardiology 11/2014; 193. DOI:10.1016/j.ijcard.2014.11.098 · 4.04 Impact Factor
  • International Journal of Cardiology 10/2014; 177(3). DOI:10.1016/j.ijcard.2014.09.090 · 4.04 Impact Factor
  • Robert Manka · Christian Binter · Sebastian Kozerke
    The Lancet 09/2014; 384(9960). DOI:10.1016/S0140-6736(14)60752-2 · 45.22 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: OBJECTIVES: To describe the use of a new extracellular matrix patch as a means for atrial reconstruction in patients with cardiac tumours. METHODS: A new extracellular matrix patch was used to reconstruct atrial and neighbouring structures after tumour resections. In 1 case, it was used to reconstruct the atrial septum and the left atrial roof after excision of a huge myxoma. In a second case, it was used to reconstruct the right atrium, including the superior vena cava after excision of a primary cardiac sarcoma. In a third case, it was used to reconstruct both atria, the right-sided pulmonary venous confluence and the roof of the coronary sinus after excision of a metastasis of malignant melanoma. RESULTS: In all cases, reconstruction was successful and facilitated because of the flexible and thin character of the extracellular matrix, which also seemed to be advantageous with regards to haemostasis. CONCLUSIONS: Extracellular matrix patches are a potential alternative for pericardial patches for complex reconstructions of atrial structures because of their pliable characteristics and consecutively reduced need for haemostatic stitches.
    Interactive Cardiovascular and Thoracic Surgery 09/2014; 20(1). DOI:10.1093/icvts/ivu310 · 1.16 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Purpose In this work we present a dual-phase diffusion tensor imaging (DTI) technique that incorporates a correction scheme for the cardiac material strain, based on 3D myocardial tagging. Methods In vivo dual-phase cardiac DTI with a stimulated echo approach and 3D tagging was performed in 10 healthy volunteers. The time course of material strain was estimated from the tagging data and used to correct for strain effects in the diffusion weighted acquisition. Mean diffusivity, fractional anisotropy, helix, transverse and sheet angles were calculated and compared between systole and diastole, with and without strain correction. Data acquired at the systolic sweet spot, where the effects of strain are eliminated, served as a reference. Results The impact of strain correction on helix angle was small. However, large differences were observed in the transverse and sheet angle values, with and without strain correction. The standard deviation of systolic transverse angles was significantly reduced from 35.9±3.9° to 27.8°±3.5° (p<0.001) upon strain-correction indicating more coherent fiber tracks after correction. Myocyte aggregate structure was aligned more longitudinally in systole compared to diastole as reflected by an increased transmural range of helix angles (71.8°±3.9° systole vs. 55.6°±5.6°, p<0.001 diastole). While diastolic sheet angle histograms had dominant counts at high sheet angle values, systolic histograms showed lower sheet angle values indicating a reorientation of myocyte sheets during contraction. Conclusion An approach for dual-phase cardiac DTI with correction for material strain has been successfully implemented. This technique allows assessing dynamic changes in myofiber architecture between systole and diastole, and emphasizes the need for strain correction when sheet architecture in the heart is imaged with a stimulated echo approach.
    PLoS ONE 09/2014; 9(9):e107159. DOI:10.1371/journal.pone.0107159 · 3.23 Impact Factor
  • M Niemann · H Alkadhi · A Gotschy · S Kozerke · R Manka
    [Show abstract] [Hide abstract]
    ABSTRACT: Fett wird seit der Entdeckung des ob-Gen-Produkts Leptin als endokrines Organ angesehen. Insbesondere dem epikardialen Fett ist in den letzten Jahren vermehrte Aufmerksamkeit geschenkt worden. Das epikardiale Fett nimmt Aufgaben im Fettmetabolismus wahr, jedoch werden ihm auch schädliche parakrine, autokrine und systemische Wirkungen zugeschrieben. Die bildmorphologische Bestimmung des epikardialen Fettvolumens gelingt mittels der Echokardiographie, der Computertomographie oder der Magnetresonanztomographie. In diesem Review sollen zunächst grundlegende Betrachtungen der Physiologie und Pathophysiologie des epikardialen Fetts skizziert werden. Der Schwerpunkt des Reviews liegt dann auf der Vorstellung der Messmethoden des epikardialen Fetts mittels der einzelnen Bildgebungsmodalitäten und einem Literaturüberblick der Assoziationen des epikardialen Fetts zu Erkrankungen des kardiovaskulären Systems wie dem metabolischen Syndrom, der Herzinsuffizienz und der koronaren Herzkrankheit. Abstract Since the discovery of the obese (ob) gene product leptin, fat has been considered an endocrine organ. Especially epicardial fat has gained increasing attention in recent years. The epicardial fat plays a major role in fat metabolism; however, harmful properties have also been reported. Echocardiography, computed tomography and cardiac magnetic resonance imaging are the non-invasive tools used to measure epicardial fat volume. This review briefly introduces the basic physiological and pathophysiological considerations concerning epicardial fat. The main issue of this review is the presentation of non-invasive measurement techniques of epicardial fat using various imaging modalities and a literature overview of associations between epicardial fat and common cardiovascular diseases.
    Herz 09/2014; 40. DOI:10.1007/s00059-014-4146-6 · 0.69 Impact Factor
  • Journal of the American College of Cardiology 09/2014; 64(11):B45. DOI:10.1016/j.jacc.2014.07.185 · 16.50 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: To investigate the use of computed tomography (CT) to measure the mitral valve annulus size before implantation of a percutaneous mitral valve annuloplasty device in an animal trial. Seven domestic pigs underwent CT before and after implantation of a Cardioband™ (a percutaneously implantable mitral valve annuloplasty device) with a second-generation 128-section dual-source CT machine. Implantation of the Cardioband™ was performed in a standard fashion according to a protocol. Animals were sacrificed afterwards and the hearts explanted. The Cardioband™ was found to be adequately implanted in all animals, with no anchor dehiscence and no damage of the circumflex artery (CX) or the coronary sinus (CS). The correct length of the band as chosen according to the length of the posterior mitral annulus measured in CT before implantation was confirmed in gross examination in all animals. The device did not result in a metal artifact-related degradation of image quality. The closest distance from the closest anchor to the CX was 2.1 ± 0.7 mm in diastole and 1.6 ± 0.5 mm systole. Mitral annulus distance to the CS was 6.4 ± 1.3 mm in diastole and 7.7 ± 1.1 mm in systole. CT visualization and measurement of the mitral valve annulus dimensions is feasible and can become the imaging method of choice for procedure planning of Cardioband™ implantations or other transcatheter mitral annuloplasty devices.
    The International Journal of Cardiovascular Imaging 08/2014; 31(1). DOI:10.1007/s10554-014-0516-7 · 1.81 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Aims: To determine the association between coronary vessel wall morphology and haemodynamic consequences to the myocardium using a combined cardiovascular magnetic resonance (CMR) imaging protocol. Non-invasive CMR profiling of coronary atherosclerotic wall changes and related myocardial blood flow impairment has not been established yet. Methods and results: Sixty-three patients (45 men, 61.5 ± 10.7 years) with suspected or known coronary artery disease underwent 3.0 Tesla CMR imaging. The combined CMR protocol consisted of the following imaging modules at rest: 3D vessel wall imaging and flow measurement of the proximal right coronary artery (RCA), myocardial T2*, and first-pass perfusion imaging. During adenosine stress coronary flow, T2* and first-pass perfusion imaging were repeated. Coronary X-ray angiography classified patient groups: (i) all-smooth (n = 19); (ii) luminal irregular (diameter reduction < 30%; n = 35); and (iii) stenosed RCA (diameter reduction ≥ 50%; n = 9). The ratio of CMR-derived vessel wall area-to-lumen area significantly increased stepwise for the comparison of all-smooth vs. luminal irregular vs. stenosed RCA (1.9 ± 0.6 vs. 2.6 ± 0.6 vs. 3.6 ± 0.9, P < 0.01). Epicardial coronary flow reserve exhibited a stepwise significant decrease (3.4 ± 0.5 vs. 2.9 ± 0.7 vs. 1.7 ± 0.3, P < 0.01). On the myocardial level, stress-induced percentage gain of T2* values (ΔT2*) was significantly decreased between groups (29.2 ± 10.6 vs. 9.0 ± 9.8 vs. 2.2 ± 11.8%, P < 0.01) while perfusion reserve index decreased in the presence of stenosed RCA only (2.2 ± 0.6 vs. 2.0 ± 0.4 vs. 1.3 ± 0.3, P = ns and P < 0.01, respectively). Conclusion: The proposed comprehensive CMR imaging protocol provided a non-invasive approach for direct assessment of coronary vessel wall remodelling and resultant pathophysiological consequences on the level of epicardial coronary and myocardial blood flow in patients.
    European Heart Journal – Cardiovascular Imaging 08/2014; 15(12). DOI:10.1093/ehjci/jeu148 · 4.11 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: To investigate the accuracy of post-mortem diffusion tensor imaging (DTI) for the detection of myocardial infarction (MI) and to demonstrate the feasibility of helix angle (HA) calculation to study remodelling of myofibre architecture. Cardiac DTI was performed in 26 deceased subjects prior to autopsy for medicolegal reasons. Fractional anisotropy (FA) and mean diffusivity (MD) were determined. Accuracy was calculated on per-segment (AHA classification), per-territory, and per-patient basis, with pathology as reference standard. HAs were calculated and compared between healthy segments and those with MI. Autopsy demonstrated MI in 61/440 segments (13.9 %) in 12/26 deceased subjects. Healthy myocardial segments had significantly higher FA (p < 0.01) and lower MD (p < 0.001) compared to segments with MI. Multivariate logistic regression demonstrated that FA (p < 0.10) and MD (p = 0.01) with the covariate post-mortem time (p < 0.01) predicted MI with an accuracy of 0.73. Analysis of HA distribution demonstrated remodelling of myofibre architecture, with significant differences between healthy segments and segments with chronic (p < 0.001) but not with acute MI (p > 0.05). Post-mortem cardiac DTI enablesdifferentiation between healthy and infarcted myocardial segments by means of FA and MD. HA assessment allows for the demonstration of remodelling of myofibre architecture following chronic MI. aEuro cent DTI enables post-mortem detection of myocardial infarction with good accuracy. aEuro cent A decrease in right-handed helical fibre indicates myofibre remodelling following chronic myocardial infarction. aEuro cent DTI allows for ruling out myocardial infarction by means of FA. aEuro cent Post-mortem DTI may represent a valuable screening tool in forensic investigations.
    European Radiology 07/2014; 24(11). DOI:10.1007/s00330-014-3322-7 · 4.01 Impact Factor

Publication Stats

844 Citations
485.21 Total Impact Points


  • 2015
    • Inselspital, Universitätsspital Bern
      Berna, Bern, Switzerland
  • 2013–2015
    • University Hospital Zürich
      Zürich, Zurich, Switzerland
  • 2009–2015
    • University of Zurich
      • Center for Integrative Human Physiology
      Zürich, Zurich, Switzerland
  • 2008–2015
    • ETH Zurich
      • Institute for Biomedical Engineering
      Zürich, Zurich, Switzerland
  • 2012
    • University Hospital of Lausanne
      Lausanne, Vaud, Switzerland
  • 2008–2011
    • Berlin Heart
      Berlín, Berlin, Germany
  • 2010
    • Deutsches Herzzentrum Berlin
      • Cardiothoracic and Vascular Surgery
      Berlín, Berlin, Germany