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MR fluoroscopy in vascular and cardiac interventions (review).

Saeed M, Hetts SW, English J, Wilson M - Int J Cardiovasc Imaging (2011)

Bottom Line: Development of more MR compatible equipment and devices will widen the applications of MR-guided procedures.At post-intervention, MR imaging aids in assessing the efficacy of therapies, success of interventions.MR fluoroscopy has the potential to form the basis for minimally invasive image-guided surgeries that offer improved patient management and cost effectiveness.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA 94107-1701, USA. Maythem.Saeed@radiology.UCSF.edu

ABSTRACT
Vascular and cardiac disease remains a leading cause of morbidity and mortality in developed and emerging countries. Vascular and cardiac interventions require extensive fluoroscopic guidance to navigate endovascular catheters. X-ray fluoroscopy is considered the current modality for real time imaging. It provides excellent spatial and temporal resolution, but is limited by exposure of patients and staff to ionizing radiation, poor soft tissue characterization and lack of quantitative physiologic information. MR fluoroscopy has been introduced with substantial progress during the last decade. Clinical and experimental studies performed under MR fluoroscopy have indicated the suitability of this modality for: delivery of ASD closure, aortic valves, and endovascular stents (aortic, carotid, iliac, renal arteries, inferior vena cava). It aids in performing ablation, creation of hepatic shunts and local delivery of therapies. Development of more MR compatible equipment and devices will widen the applications of MR-guided procedures. At post-intervention, MR imaging aids in assessing the efficacy of therapies, success of interventions. It also provides information on vascular flow and cardiac morphology, function, perfusion and viability. MR fluoroscopy has the potential to form the basis for minimally invasive image-guided surgeries that offer improved patient management and cost effectiveness.

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Photomicrographs of representative infarctions in control (a, b) and VEGF gene–treated animals (c, d). Sections a and c were stained with Masson trichrome stain, while b and d were stained with biotinylated isolectin B4. Sections a and c show chronic infarction (I) in both groups which is comprised of homogeneous replacement fibrosis with a distinct boundary at the interface between scar and viable myocardium (M). Treated animal contained numerous vessels c, d) (arrows), while control infarction contained very few vessels. Biotinylated isolectin B4 localized vessels with brown reaction product, accentuating the neovascularity in VEGF gene–treated infarct (d) as compared with infarct in control animal (b). Calibration bars = 80 μm
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Fig9: Photomicrographs of representative infarctions in control (a, b) and VEGF gene–treated animals (c, d). Sections a and c were stained with Masson trichrome stain, while b and d were stained with biotinylated isolectin B4. Sections a and c show chronic infarction (I) in both groups which is comprised of homogeneous replacement fibrosis with a distinct boundary at the interface between scar and viable myocardium (M). Treated animal contained numerous vessels c, d) (arrows), while control infarction contained very few vessels. Biotinylated isolectin B4 localized vessels with brown reaction product, accentuating the neovascularity in VEGF gene–treated infarct (d) as compared with infarct in control animal (b). Calibration bars = 80 μm

Mentions: Gene therapy is a new approach for treating ischemic heart disease and it is an exciting area of modern medicine. Recent MR-guided studies demonstrated the success of catheter-based transendocardial delivery of genes (Fig. 2). Preclinical studies have indicated that MR imaging provides quantitative data on infarct size, infarct transmurality, microvascular obstruction and hemorrhage). These capabilities have positioned MR imaging as an important approach to persue for assessing the benefits of locally delivered genes [20]. The MR-guided approach for delivering plasmid-VEGF gene has been validated using histopathology as a gold standard, which ensured the efficacy of delivered therapy into infarcted myocardium by demonstrating the formation of new blood vessels in treated animals (Fig. 9). Another MR study showed the increase in collateral blood flow of infarcted myocardium after delivering vascular endothelial growth factor [184]. Post et al. [185] demonstrated an improvement in regional radial strain after intramyocardial injection of adenovirus coding for P39 gene. Furthermore, Liu et al. found a significant improvement in LV ejection fraction and smaller number of segments with wall motion abnormality after intramyocardial injection of fibroblast growth factor [186].Fig. 9


MR fluoroscopy in vascular and cardiac interventions (review).

Saeed M, Hetts SW, English J, Wilson M - Int J Cardiovasc Imaging (2011)

Photomicrographs of representative infarctions in control (a, b) and VEGF gene–treated animals (c, d). Sections a and c were stained with Masson trichrome stain, while b and d were stained with biotinylated isolectin B4. Sections a and c show chronic infarction (I) in both groups which is comprised of homogeneous replacement fibrosis with a distinct boundary at the interface between scar and viable myocardium (M). Treated animal contained numerous vessels c, d) (arrows), while control infarction contained very few vessels. Biotinylated isolectin B4 localized vessels with brown reaction product, accentuating the neovascularity in VEGF gene–treated infarct (d) as compared with infarct in control animal (b). Calibration bars = 80 μm
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3275732&req=5

Fig9: Photomicrographs of representative infarctions in control (a, b) and VEGF gene–treated animals (c, d). Sections a and c were stained with Masson trichrome stain, while b and d were stained with biotinylated isolectin B4. Sections a and c show chronic infarction (I) in both groups which is comprised of homogeneous replacement fibrosis with a distinct boundary at the interface between scar and viable myocardium (M). Treated animal contained numerous vessels c, d) (arrows), while control infarction contained very few vessels. Biotinylated isolectin B4 localized vessels with brown reaction product, accentuating the neovascularity in VEGF gene–treated infarct (d) as compared with infarct in control animal (b). Calibration bars = 80 μm
Mentions: Gene therapy is a new approach for treating ischemic heart disease and it is an exciting area of modern medicine. Recent MR-guided studies demonstrated the success of catheter-based transendocardial delivery of genes (Fig. 2). Preclinical studies have indicated that MR imaging provides quantitative data on infarct size, infarct transmurality, microvascular obstruction and hemorrhage). These capabilities have positioned MR imaging as an important approach to persue for assessing the benefits of locally delivered genes [20]. The MR-guided approach for delivering plasmid-VEGF gene has been validated using histopathology as a gold standard, which ensured the efficacy of delivered therapy into infarcted myocardium by demonstrating the formation of new blood vessels in treated animals (Fig. 9). Another MR study showed the increase in collateral blood flow of infarcted myocardium after delivering vascular endothelial growth factor [184]. Post et al. [185] demonstrated an improvement in regional radial strain after intramyocardial injection of adenovirus coding for P39 gene. Furthermore, Liu et al. found a significant improvement in LV ejection fraction and smaller number of segments with wall motion abnormality after intramyocardial injection of fibroblast growth factor [186].Fig. 9

Bottom Line: Development of more MR compatible equipment and devices will widen the applications of MR-guided procedures.At post-intervention, MR imaging aids in assessing the efficacy of therapies, success of interventions.MR fluoroscopy has the potential to form the basis for minimally invasive image-guided surgeries that offer improved patient management and cost effectiveness.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA 94107-1701, USA. Maythem.Saeed@radiology.UCSF.edu

ABSTRACT
Vascular and cardiac disease remains a leading cause of morbidity and mortality in developed and emerging countries. Vascular and cardiac interventions require extensive fluoroscopic guidance to navigate endovascular catheters. X-ray fluoroscopy is considered the current modality for real time imaging. It provides excellent spatial and temporal resolution, but is limited by exposure of patients and staff to ionizing radiation, poor soft tissue characterization and lack of quantitative physiologic information. MR fluoroscopy has been introduced with substantial progress during the last decade. Clinical and experimental studies performed under MR fluoroscopy have indicated the suitability of this modality for: delivery of ASD closure, aortic valves, and endovascular stents (aortic, carotid, iliac, renal arteries, inferior vena cava). It aids in performing ablation, creation of hepatic shunts and local delivery of therapies. Development of more MR compatible equipment and devices will widen the applications of MR-guided procedures. At post-intervention, MR imaging aids in assessing the efficacy of therapies, success of interventions. It also provides information on vascular flow and cardiac morphology, function, perfusion and viability. MR fluoroscopy has the potential to form the basis for minimally invasive image-guided surgeries that offer improved patient management and cost effectiveness.

Show MeSH
Related in: MedlinePlus