1
|
Pica S, Di Giovine G, Bollati M, Testa L, Bedogni F, Camporeale A, Pontone G, Andreini D, Monti L, Gasparini G, Grancini L, Secco GG, Maestroni A, Ambrogi F, Milani V, Lombardi M. Cardiac magnetic resonance for ischaemia and viability detection. Guiding patient selection to revascularization in coronary chronic total occlusions: The CARISMA_CTO study design. Int J Cardiol 2018; 272:356-362. [PMID: 30173921 DOI: 10.1016/j.ijcard.2018.08.061] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2018] [Revised: 07/21/2018] [Accepted: 08/20/2018] [Indexed: 01/16/2023]
Abstract
BACKGROUND It is debated whether percutaneous revascularization (PCI) of total coronary chronic occlusion (CTO) is superior to optimal medical therapy (OMT) in improving symptoms, left ventricular (LV) function and major adverse cardiac/cerebrovascular events (MACCE). Furthermore, CTO-PCI is a challenging technique, with lower success rate than in other settings. A systematic analysis of baseline LV function, infarction extent and ischaemic burden to predict response to revascularization has never been performed. PURPOSES To establish a CMR protocol to identify patients (pts) who can benefit most from CTO-PCI. Myocardial viability/ischaemia retains high biological plausibility as predictors of response to revascularization. Therefore, baseline viability (necrotic tissue extent, response to inotropic stimulation) and ischaemia (perfusion defect, wall motion abnormality during stress) will be studied as potential predictors of mechanical LV segmental improvement and ischaemic burden reduction in CTO territory (primary endpoint), LV remodelling and global function, Seattle Angina Questionnaire, and MACCE improvement (secondary endpoints) in the follow-up. METHODS Pts with CTO suitable for PCI undergo stress-CMR for viability/ischaemia assessment. Pts with normal LV function undergo adenosine, those with moderately-reduced ejection fraction (EF) and wall motion abnormalities high-dose dobutamine, pts with EF <35% low-dose dobutamine. All pts undergo late gadolinium enhancement and repeat the same scan at 12 ± 3 months, regardless of PCI success or decision for OMT. CONCLUSIONS A multi-parameter CMR protocol tailored on pts characteristics to study viability/ischaemia could help in identifying responders in terms of LV function, ischaemic burden and clinical outcome among pts suitable for CTO-PCI, improving selection of best candidates to percutaneous revascularization.
Collapse
Affiliation(s)
- S Pica
- Multimodality Cardiac Imaging Section, IRCCS Policlinico San Donato, San Donato Milanese, Milan, Italy.
| | - G Di Giovine
- Multimodality Cardiac Imaging Section, IRCCS Policlinico San Donato, San Donato Milanese, Milan, Italy
| | - M Bollati
- Cardiology Department, IRCCS Policlinico San Donato, San Donato Milanese, Milan, Italy
| | - L Testa
- Cardiology Department, IRCCS Policlinico San Donato, San Donato Milanese, Milan, Italy
| | - F Bedogni
- Cardiology Department, IRCCS Policlinico San Donato, San Donato Milanese, Milan, Italy
| | - A Camporeale
- Multimodality Cardiac Imaging Section, IRCCS Policlinico San Donato, San Donato Milanese, Milan, Italy
| | - G Pontone
- Centro Cardiologico Monzino, IRCCS, Milan, Italy
| | - D Andreini
- Centro Cardiologico Monzino, IRCCS, Milan, Italy
| | - L Monti
- Istituto Clinico Humanitas, Rozzano, Milan, Italy
| | - G Gasparini
- Istituto Clinico Humanitas, Rozzano, Milan, Italy
| | - L Grancini
- Centro Cardiologico Monzino, IRCCS, Milan, Italy
| | - G G Secco
- A.O.Ss. Antonio e Biagio, Alessandria, Italy
| | - A Maestroni
- ASTT Valle Olona, Busto Arsizio, Varese, Italy
| | - F Ambrogi
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - V Milani
- Scientific Directorate, IRCCS Policlinico San Donato, San Donato Milanese, Milan, Italy
| | - M Lombardi
- Multimodality Cardiac Imaging Section, IRCCS Policlinico San Donato, San Donato Milanese, Milan, Italy
| |
Collapse
|
2
|
Liu G, Qi XL, Robert N, Dick AJ, Wright GA. Ultrasound-guided identification of cardiac imaging windows. Med Phys 2012; 39:3009-18. [PMID: 22755685 DOI: 10.1118/1.4711757] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE Currently, the use of cine magnetic resonance imaging (MRI) to identify cardiac quiescent periods relative to the electrocardiogram (ECG) signal is insufficient for producing submillimeter-resolution coronary MR angiography (MRA) images. In this work, the authors perform a time series comparison between tissue Doppler echocardiograms of the interventricular septum (IVS) and concurrent biplane x-ray angiograms. Our results indicate very close agreement between the diastasis gating windows identified by both the IVS and x-ray techniques. METHODS Seven cath lab patients undergoing diagnostic angiograms were simultaneously scanned during a breath hold by ultrasound and biplane x-ray for six to eight heartbeats. The heart rate of each patient was stable. Dye was injected into either the left or right-coronary vasculature. The IVS was imaged using color tissue Doppler in an apical four-chamber view. Diastasis was estimated on the IVS velocity curve. On the biplane angiograms, proximal, mid, and distal regions were identified on the coronary artery (CA). Frame by frame correlation was used to derive displacement, and then velocity, for each region. The quiescent periods for a CA and its subsegments were estimated based on velocity. Using Pearson's correlation coefficient and Bland-Altman analysis, the authors compared the start and end times of the diastasis windows as estimated from the IVS and CA velocities. The authors also estimated the vessel blur across the diastasis windows of multiple sequential heartbeats of each patient. RESULTS In total, 17 heartbeats were analyzed. The range of heart rate observed across patients was 47-79 beats per minute (bpm) with a mean of 57 bpm. Significant correlations (R > 0.99; p < 0.01) were observed between the IVS and x-ray techniques for the identification of the start and end times of diastasis windows. The mean difference in the starting times between IVS and CA quiescent windows was -12.0 ms. The mean difference in end times between IVS and CA quiescent windows was -3.5 ms. In contrast, the correlation between RR interval and both the start and duration of the x-ray gating windows were relatively weaker: R = 0.63 (p = 0.13) and R = 0.86 (p = 0.01). For IVS gating windows, the average estimated vessel blurs during single and multiple heartbeats were 0.5 and 0.66 mm, respectively. For x-ray gating windows, the corresponding values were 0.26 and 0.44 mm, respectively. CONCLUSIONS In this study, the authors showed that IVS velocity can be used to identify periods of diastasis for coronary arteries. Despite variability in mid-diastolic rest positions over multiple steady rate heartbeats, vessel blurring of 0.5-1 mm was found to be achievable using the IVS gating technique. The authors envision this leading to a new cardiac gating system that, compared with conventional ECG gating, provides better resolution and shorter scan times for coronary MRA.
Collapse
Affiliation(s)
- Garry Liu
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario M4N 3M5, Canada.
| | | | | | | | | |
Collapse
|
3
|
Qian D, Bottomley PA. High-resolution intravascular magnetic resonance quantification of atherosclerotic plaque at 3T. J Cardiovasc Magn Reson 2012; 14:20. [PMID: 22448884 PMCID: PMC3340302 DOI: 10.1186/1532-429x-14-20] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2011] [Accepted: 03/26/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The thickness of fibrous caps (FCT) of atherosclerotic lesions is a critical factor affecting plaque vulnerability to rupture. This study tests whether 3 Tesla high-resolution intravascular cardiovascular magnetic resonance (CMR) employing tiny loopless detectors can identify lesions and accurately measure FCT in human arterial specimens, and whether such an approach is feasible in vivo using animal models. METHODS Receive-only 2.2 mm and 0.8 mm diameter intravascular loopless CMR detectors were fabricated for a clinical 3 Tesla MR scanner, and the absolute signal-to-noise ratio determined. The detectors were applied in a two-step protocol comprised of CMR angiography to identify atherosclerotic lesions, followed by high-resolution CMR to characterize FCT, lesion size, and/or vessel wall thickness. The protocol was applied in fresh human iliac and carotid artery specimens in a human-equivalent saline bath. Mean FCT measured by 80 μm intravascular CMR was compared with histology of the same sections. In vivo studies compared aortic wall thickness and plaque size in healthy and hyperlipidemic rabbit models, with post-mortem histology. RESULTS Histology confirmed plaques in human specimens, with calcifications appearing as signal voids. Mean FCT agreed with histological measurements within 13% on average (correlation coefficient, R = 0.98; Bland-Altman analysis, -1.3 ± 68.9 μm). In vivo aortic wall and plaque size measured by 80 μm intravascular CMR agreed with histology. CONCLUSION Intravascular 3T CMR with loopless detectors can both locate atherosclerotic lesions, and accurately measure FCT at high-resolution in a strategy that appears feasible in vivo. The approach shows promise for quantifying vulnerable plaque for evaluating experimental therapies.
Collapse
Affiliation(s)
- Di Qian
- Division of MR Research, Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, MD, USA
| | - Paul A Bottomley
- Division of MR Research, Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, MD, USA
- Division of MR Research, Department of Radiology and Radiological Science, Johns Hopkins School of Medicine, 600 N Wolfe St, Park 310, Baltimore, MD, USA
| |
Collapse
|
4
|
Sathyanarayana S, Bottomley PA. MRI endoscopy using intrinsically localized probes. Med Phys 2009; 36:908-19. [PMID: 19378751 DOI: 10.1118/1.3077125] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Magnetic resonance imaging (MRI) is traditionally performed with fixed externally applied gradient magnetic fields and is hence intrinsically locked to the laboratory frame of reference (FoR). Here a method for high-resolution MRI that employs active, catheter-based, tiny internal probes that utilize the spatial properties of the probe itself for localization is proposed and demonstrated at 3 T. Because these properties are intrinsic to the probe, they move with it, transforming MRI from the laboratory FoR to the FoR of the device itself, analogous to an endoscope. The "MRI endoscope" can utilize loop coils and loopless antennas with modified sensitivity, in combination with adiabatic excitation by the device itself, to restrict the MRI sensitivity to a disk-shaped plane a few mm thick. Excitation with the MRI endoscope limits the eddy currents induced in the sample to an excited volume whose size is orders of magnitude below that excited by a conventional body MRI coil. Heat testing shows maximum local temperature increases of <1 degrees C during MRI, within regulatory guidelines. The method is demonstrated in a kiwifruit, in intact porcine and rabbit aortas, and in an atherosclerotic human iliac artery specimen, with in-plane resolution as small as 80 microm and 1.5-5 mm slice thickness.
Collapse
Affiliation(s)
- Shashank Sathyanarayana
- Department of Radiology, Division of MR Research, Johns Hopkins University, Baltimore, Maryland 21287, USA
| | | |
Collapse
|
5
|
Chamié D, Abizaid A, Júnior JRC, Feres F, Abizaid A, Staico R, Costa R, Mattos LAP, Sousa AG, Sousa JE. The revascular active percutaneous interventional device for coronary total occlusions study. Catheter Cardiovasc Interv 2008; 72:156-63. [DOI: 10.1002/ccd.21560] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
6
|
Sampath S, Raval AN, Lederman RJ, McVeigh ER. High-resolution 3D arteriography of chronic total peripheral occlusions using a T1-W turbo spin-echo sequence with inner-volume imaging. Magn Reson Med 2007; 57:40-9. [PMID: 17152076 PMCID: PMC2396253 DOI: 10.1002/mrm.21098] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Percutaneous revascularization of peripheral artery chronic total occlusion (CTO) is challenging under X-ray guidance without direct image feedback, due to poor visualization of the obstructed segment and underappreciation of vessel tortuosity. Operators are required to steer interventional devices relatively "blindly," and therefore procedural failure or perforation may occur. Alternatively, MRI may allow complete visualization of both patent and occluded arterial segments. We designed and implemented a 3D high-resolution, T(1)-weighted (T(1)-W) turbo spin-echo (TSE) MRI sequence with inner-volume (IV) imaging to enable detailed peripheral artery CTO imaging. Using this sequence, high-resolution volumes of interest (VOIs) around the vessel were achieved within 5-10 min. This imaging approach may be used for rapid pre- and postprocedural evaluations, and as a 3D roadmap that can be overlaid during real-time X-, MR-, or XMR-guided catheterization. Experiments were successfully performed on a carotid CTO model in swine ex vivo, and in peripheral arteries in normal volunteers and patients in vivo. Delineation of the vascular architecture, including contrast differences between the patent and occluded artery segments, and lesion morphology heterogeneity were visualized.
Collapse
Affiliation(s)
- Smita Sampath
- Laboratory of Cardiac Energetics, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, DHHS, Bethesda, Maryland 20892-1061, USA.
| | | | | | | |
Collapse
|