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First fusion and combined evaluation of 3D-CMR perfusion with 3D-MR coronary angiography
International Journal of Cardiology 202 (2016) 62–63
Contents lists available at ScienceDirect
International Journal of Cardiology journal homepage: www.elsevier.com/locate/ijcard
Letter to the Editor
First fusion and combined evaluation of 3D-CMR perfusion with 3D-MR coronary angiography Alexander Gotschy a,b,c, Lukas Wissmann b, Datta Singh Goolaub b, Markus Niemann a,b, Sandra Hamada d, Sebastian Kozerke b,e, Robert Manka a,b,d,⁎ a
Department of Cardiology, University Heart Center, University Hospital Zurich, Zurich, Switzerland Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland Division of Internal Medicine, University Hospital Zurich, Zurich, Switzerland d Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, Zurich, Switzerland e Imaging Sciences and Biomedical Engineering, King's College, London, United Kingdom b c
a r t i c l e
i n f o
Article history: Received 10 August 2015 Accepted 21 August 2015 Available online 24 August 2015 Keywords: Magnetic resonance perfusion Magnetic resonance angiography Coronary artery disease
The most relevant parameters for the assessment of coronary artery disease (CAD) are myocardial perfusion and the status of the coronary arteries. It has been shown that hybrid imaging strategies to acquire both parameters such as SPECT with CT-angiography provide an added value for clinical decision making in the treatment of CAD [1]. Thus the 2014 ESC Guidelines, for the first time, recommend hybrid imaging for planning myocardial revascularization [2]. However, SPECT and CT expose the patient to ionizing radiation and, in large prospective multicentre trials, SPECT showed inferior sensitivity to detect CAD when compared with standard 2D-CMR perfusion [3]. Therefore, the aim of this study was to investigate the feasibility and potential additive value of MR-based hybrid imaging by the combined assessment and fusion of 3D-MR coronary angiography (MRCA) with 3D-CMR perfusion data [4]. In this study, eleven patients (59 ± 14 years, 11 males) with suspected CAD were scheduled for invasive X-ray coronary angiography (XA) and a CMR examination. The CMR protocol consisted of adenosine stress–rest 3D-CMR perfusion, late gadolinium enhancement (LGE) and MRCA examinations. All examinations were performed on a 3 T clinical
⁎ Corresponding author at: Department of Cardiology, University Heart Center, University Hospital Zurich, Raemistrasse 100, 8091 Zurich, Switzerland. E-mail address: [email protected] (R. Manka).
http://dx.doi.org/10.1016/j.ijcard.2015.08.165 0167-5273/© 2015 Elsevier Ireland Ltd. All rights reserved.
scanner. In XA, coronary stenosis ≥50% was classified as significant. Informed consent was obtained from each patient and the study protocol conforms to the 1975 Declaration of Helsinki and was approved by the local human research committee. Myocardial ischemic burden (MIB, %) was determined by hypoperfused regions in the CMR perfusion images excluding scar tissue as obtained from LGE images and normalized to left-ventricular myocardial volume. For the segmentation of the MIB, hypoperfused regions were defined as regions with a signal-intensity N2 SDs below the signal of remote myocardium and MIB N 4.1% was considered significant ischemia [5]. MRCA scans were evaluated by an experienced reader and each vessel was graded as no/low-grade stenosis or significant stenosis. Additional fusion of 3D-MRCA and 3D-CMR perfusion was performed. All MIB data and 91% of the vessels in the MRCA could be evaluated successfully. CAD prevalence as defined by XA was 73% (8 of 11 patients, 16 of 33 vessels). In a vessel-based analysis, MRCA had 75% sensitivity, 79% specificity, a positive predictive value (PPV) of 80%, and a negative predictive value (NPV) of 73%. MIB evaluations had 75% sensitivity, 100% specificity, a PPV of 100%, and a NPV of 81%. Combined evaluation of MRCA with MIB resulted in 94% sensitivity, 82% specificity, a PPV of 83%, and a NPV of 93%. Additional fusion of MRCA with CMR-perfusion scans depicts the coronary anatomy and significant coronary stenosis in relation to the resulting perfusion deficits. The transmural resolution of 3D-CMR perfusion allows the visualization of subendocardial (defined as the inner 50% of the myocardium) and subepicardial (defined as the outer 50% of the myocardium) perfusion separately (Fig. 1). In previous trials, the combined determination of anatomical and functional data obtained with CT angiography and MRI proved to provide complementary information for the assessment of CAD [6]. However, when using CT-angiography or MRCA with CMR-perfusion “side-by-side” without fusion, the complimentary information on coronary artery anatomy and the myocardial ischemia has to be integrated mentally, based on the AHA 17 segment model. Unfortunately, in only 50–60% of cases the real anatomic tree corresponds to the standard myocardial distribution territories [7]. Therefore, in particular in multivessel disease, the co-visualization of the real coronary tree with the underlying myocardial perfusion has the potential to unambiguously correlate coronary stenoses with non-distinct perfusion deficits. In our
Letter to the Editor
63
Fig. 1. This 32 year-old patient was referred to our hospital with stable angina for 3 months. He had no history of cardiovascular disease and a dyslipidemia as only cardiovascular risk factor. MRCA (A & C) and X-ray coronary angiography (B) reveal a high grade LAD stenosis (green arrows). 3D fusion of MRCA with CMR perfusion shows no distinct perfusion deficit in the epicardial layer (D) but large subendocardial ischemia in the LAD territory (E) which can also be seen in the 3D-CMR perfusion image (F) while LGE imaging shows no myocardial scar (G).
study functional and anatomical information was obtained in a single MR examination. The feasibility of 3D reconstruction and fusion of both scans as well as the visualization of different myocardial layers could be shown. Combined evaluation of 3D-MRCA with 3D-CMR perfusion had superior sensitivity at the cost of a loss in specificity when compared to CMR-perfusion alone in a vessel-based approach. Conflict of interest The authors report no relationships that could be construed as a conflict of interest. Acknowledgments The authors acknowledge the support from the Swiss National Science Foundation, Grant # CR3213_132671/1, Bayer Healthcare and Philips Healthcare. References [1] A.P. Pazhenkottil, R.N. Nkoulou, J.R. Ghadri, et al., Impact of cardiac hybrid single-photon emission computed tomography/computed tomography imaging on choice of treatment strategy in coronary artery disease, Eur. Heart J. 32 (2011) 2824–2829.
[2] S. Windecker, P. Kolh, F. Alfonso, et al., 2014 ESC/EACTS Guidelines on myocardial revascularization: The Task Force on Myocardial Revascularization of the European Society of Cardiology (ESC) and the European Association for Cardio-Thoracic Surgery (EACTS). Developed with the special contribution of the European Association of Percutaneous Cardiovascular Interventions (EAPCI), Eur. Heart J. 35 (2014) 2541–2619. [3] J. Schwitter, C.M. Wacker, A.C. van Rossum, et al., MR-IMPACT: comparison of perfusion-cardiac magnetic resonance with single-photon emission computed tomography for the detection of coronary artery disease in a multicentre, multivendor, randomized trial, Eur. Heart J. 29 (2008) 480–489. [4] R. Manka, C. Jahnke, S. Kozerke, et al., Dynamic 3-dimensional stress cardiac magnetic resonance perfusion imaging: detection of coronary artery disease and volumetry of myocardial hypoenhancement before and after coronary stenting, J. Am. Coll. Cardiol. 57 (2011) 437–444. [5] R. Manka, L. Wissmann, R. Gebker, et al., Multicenter evaluation of dynamic threedimensional magnetic resonance myocardial perfusion imaging for the detection of coronary artery disease defined by fractional flow reserve, Circ. Cardiovasc. Imaging 8 (2015). [6] J.M. van Werkhoven, M.W. Heijenbrok, J.D. Schuijf, et al., Combined non-invasive anatomical and functional assessment with MSCT and MRI for the detection of significant coronary artery disease in patients with an intermediate pre-test likelihood, Heart 96 (2010) 425–431. [7] H. Kalbfleisch, W. Hort, Quantitative study on the size of coronary artery supplying areas postmortem, Am. Heart J. 94 (1977) 183–188.
Contents lists available at ScienceDirect
International Journal of Cardiology journal homepage: www.elsevier.com/locate/ijcard
Letter to the Editor
First fusion and combined evaluation of 3D-CMR perfusion with 3D-MR coronary angiography Alexander Gotschy a,b,c, Lukas Wissmann b, Datta Singh Goolaub b, Markus Niemann a,b, Sandra Hamada d, Sebastian Kozerke b,e, Robert Manka a,b,d,⁎ a
Department of Cardiology, University Heart Center, University Hospital Zurich, Zurich, Switzerland Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland Division of Internal Medicine, University Hospital Zurich, Zurich, Switzerland d Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, Zurich, Switzerland e Imaging Sciences and Biomedical Engineering, King's College, London, United Kingdom b c
a r t i c l e
i n f o
Article history: Received 10 August 2015 Accepted 21 August 2015 Available online 24 August 2015 Keywords: Magnetic resonance perfusion Magnetic resonance angiography Coronary artery disease
The most relevant parameters for the assessment of coronary artery disease (CAD) are myocardial perfusion and the status of the coronary arteries. It has been shown that hybrid imaging strategies to acquire both parameters such as SPECT with CT-angiography provide an added value for clinical decision making in the treatment of CAD [1]. Thus the 2014 ESC Guidelines, for the first time, recommend hybrid imaging for planning myocardial revascularization [2]. However, SPECT and CT expose the patient to ionizing radiation and, in large prospective multicentre trials, SPECT showed inferior sensitivity to detect CAD when compared with standard 2D-CMR perfusion [3]. Therefore, the aim of this study was to investigate the feasibility and potential additive value of MR-based hybrid imaging by the combined assessment and fusion of 3D-MR coronary angiography (MRCA) with 3D-CMR perfusion data [4]. In this study, eleven patients (59 ± 14 years, 11 males) with suspected CAD were scheduled for invasive X-ray coronary angiography (XA) and a CMR examination. The CMR protocol consisted of adenosine stress–rest 3D-CMR perfusion, late gadolinium enhancement (LGE) and MRCA examinations. All examinations were performed on a 3 T clinical
⁎ Corresponding author at: Department of Cardiology, University Heart Center, University Hospital Zurich, Raemistrasse 100, 8091 Zurich, Switzerland. E-mail address: [email protected] (R. Manka).
http://dx.doi.org/10.1016/j.ijcard.2015.08.165 0167-5273/© 2015 Elsevier Ireland Ltd. All rights reserved.
scanner. In XA, coronary stenosis ≥50% was classified as significant. Informed consent was obtained from each patient and the study protocol conforms to the 1975 Declaration of Helsinki and was approved by the local human research committee. Myocardial ischemic burden (MIB, %) was determined by hypoperfused regions in the CMR perfusion images excluding scar tissue as obtained from LGE images and normalized to left-ventricular myocardial volume. For the segmentation of the MIB, hypoperfused regions were defined as regions with a signal-intensity N2 SDs below the signal of remote myocardium and MIB N 4.1% was considered significant ischemia [5]. MRCA scans were evaluated by an experienced reader and each vessel was graded as no/low-grade stenosis or significant stenosis. Additional fusion of 3D-MRCA and 3D-CMR perfusion was performed. All MIB data and 91% of the vessels in the MRCA could be evaluated successfully. CAD prevalence as defined by XA was 73% (8 of 11 patients, 16 of 33 vessels). In a vessel-based analysis, MRCA had 75% sensitivity, 79% specificity, a positive predictive value (PPV) of 80%, and a negative predictive value (NPV) of 73%. MIB evaluations had 75% sensitivity, 100% specificity, a PPV of 100%, and a NPV of 81%. Combined evaluation of MRCA with MIB resulted in 94% sensitivity, 82% specificity, a PPV of 83%, and a NPV of 93%. Additional fusion of MRCA with CMR-perfusion scans depicts the coronary anatomy and significant coronary stenosis in relation to the resulting perfusion deficits. The transmural resolution of 3D-CMR perfusion allows the visualization of subendocardial (defined as the inner 50% of the myocardium) and subepicardial (defined as the outer 50% of the myocardium) perfusion separately (Fig. 1). In previous trials, the combined determination of anatomical and functional data obtained with CT angiography and MRI proved to provide complementary information for the assessment of CAD [6]. However, when using CT-angiography or MRCA with CMR-perfusion “side-by-side” without fusion, the complimentary information on coronary artery anatomy and the myocardial ischemia has to be integrated mentally, based on the AHA 17 segment model. Unfortunately, in only 50–60% of cases the real anatomic tree corresponds to the standard myocardial distribution territories [7]. Therefore, in particular in multivessel disease, the co-visualization of the real coronary tree with the underlying myocardial perfusion has the potential to unambiguously correlate coronary stenoses with non-distinct perfusion deficits. In our
Letter to the Editor
63
Fig. 1. This 32 year-old patient was referred to our hospital with stable angina for 3 months. He had no history of cardiovascular disease and a dyslipidemia as only cardiovascular risk factor. MRCA (A & C) and X-ray coronary angiography (B) reveal a high grade LAD stenosis (green arrows). 3D fusion of MRCA with CMR perfusion shows no distinct perfusion deficit in the epicardial layer (D) but large subendocardial ischemia in the LAD territory (E) which can also be seen in the 3D-CMR perfusion image (F) while LGE imaging shows no myocardial scar (G).
study functional and anatomical information was obtained in a single MR examination. The feasibility of 3D reconstruction and fusion of both scans as well as the visualization of different myocardial layers could be shown. Combined evaluation of 3D-MRCA with 3D-CMR perfusion had superior sensitivity at the cost of a loss in specificity when compared to CMR-perfusion alone in a vessel-based approach. Conflict of interest The authors report no relationships that could be construed as a conflict of interest. Acknowledgments The authors acknowledge the support from the Swiss National Science Foundation, Grant # CR3213_132671/1, Bayer Healthcare and Philips Healthcare. References [1] A.P. Pazhenkottil, R.N. Nkoulou, J.R. Ghadri, et al., Impact of cardiac hybrid single-photon emission computed tomography/computed tomography imaging on choice of treatment strategy in coronary artery disease, Eur. Heart J. 32 (2011) 2824–2829.
[2] S. Windecker, P. Kolh, F. Alfonso, et al., 2014 ESC/EACTS Guidelines on myocardial revascularization: The Task Force on Myocardial Revascularization of the European Society of Cardiology (ESC) and the European Association for Cardio-Thoracic Surgery (EACTS). Developed with the special contribution of the European Association of Percutaneous Cardiovascular Interventions (EAPCI), Eur. Heart J. 35 (2014) 2541–2619. [3] J. Schwitter, C.M. Wacker, A.C. van Rossum, et al., MR-IMPACT: comparison of perfusion-cardiac magnetic resonance with single-photon emission computed tomography for the detection of coronary artery disease in a multicentre, multivendor, randomized trial, Eur. Heart J. 29 (2008) 480–489. [4] R. Manka, C. Jahnke, S. Kozerke, et al., Dynamic 3-dimensional stress cardiac magnetic resonance perfusion imaging: detection of coronary artery disease and volumetry of myocardial hypoenhancement before and after coronary stenting, J. Am. Coll. Cardiol. 57 (2011) 437–444. [5] R. Manka, L. Wissmann, R. Gebker, et al., Multicenter evaluation of dynamic threedimensional magnetic resonance myocardial perfusion imaging for the detection of coronary artery disease defined by fractional flow reserve, Circ. Cardiovasc. Imaging 8 (2015). [6] J.M. van Werkhoven, M.W. Heijenbrok, J.D. Schuijf, et al., Combined non-invasive anatomical and functional assessment with MSCT and MRI for the detection of significant coronary artery disease in patients with an intermediate pre-test likelihood, Heart 96 (2010) 425–431. [7] H. Kalbfleisch, W. Hort, Quantitative study on the size of coronary artery supplying areas postmortem, Am. Heart J. 94 (1977) 183–188.