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Christopher J. White - One of the best experts on this subject based on the ideXlab platform.

  • Coronary Thrombi Increase PTCA Risk Angioscopy as a Clinical Tool
    Circulation, 1996
    Co-Authors: Christopher J. White, Stephen R. Ramee, Tyrone J. Collins, Richard R. Heuser, Alvaro Escobar, Arun K. Karsan, Dinesh Shaw, Suresh P. Jain, Theodore A. Bass, Paul S. Teirstein
    Abstract:

    Background The presence of angiographically identified intracoronary thrombus has been variably associated with complications after coronary angioplasty. Angiography has been shown to be less sensitive than Angioscopy for detecting subtle details of intracoronary morphology, such as intracoronary thrombi. The clinical importance of thrombi detectable by Angioscopy but not by angiography is not known. Methods and Results Percutaneous coronary Angioscopy was performed in 122 patients undergoing conventional coronary balloon angioplasty (PTCA) at six medical centers. Unstable angina was present in 95 patients (78%) and stable angina in 27 (22%). Therapy was not guided by angioscopic findings, and no patient received thrombolytic therapy as an adjunct to angioplasty. Coronary thrombi were identified in 74 target lesions (61%) by Angioscopy versus only 24 (20%) by angiography. A major in-hospital complication (death, myocardial infarction, or emergency bypass surgery) occurred in 10 of 74 patients (14%) with a...

  • Coronary Angioscopy of abrupt occlusion after angioplasty
    Journal of the American College of Cardiology, 1995
    Co-Authors: Christopher J. White, Stephen R. Ramee, Tyrone J. Collins, Suresh Jain, Alvaro Escobar
    Abstract:

    Abstract Objectives. This study used Angioscopy to determine the specific cause of vessel occlusion after percutaneous transluminal coronary angioplasty and compared the angiographic and angioscopic lesion morphologies in this setting. Background. Occlusion of a dilated coronary artery is the major cause of morbidity and mortality after coronary angioplasty. Attempts to reopen occluded vessels are either empirically guided or directed by angiography, which has inherent limitations. Angioscopy, the in vivo direct visualization of the endovascular surface, is potentially a more accurate means of identifying the cause of vessel occlusion after angioplasty. Methods. Percutaneous coronary Angioscopy was performed in 17 patients (17 vessels) after angiographic confirmation of postangioplasty vessel occlusion. Results. Angioscopy demonstrated the primary cause of the postangioplasty occlusion to be dissection in 14 patients (82%) and intracoronary thrombi in 3 (18%). Compared with Angioscopy, angiography was significantly less accurate in identifying the specific cause of the occlusion and correctly identified the cause of vessel occlusion in only 5 (29%) of 17 patients (p Conclusions. Angioscopy specifically identified the cause of occlusion in every patient, with coronary dissection the predominant cause of abrupt occlusion after coronary angioplasty. However, angiography was unable to identifiy a specific cause for vessel occlusion in the majority of our patients. Angioscopy may therefore prove useful in selecting specific treatment strategies for patients with abrupt occlusion after angioplasty, such as stent placement, atherectomy, repeat dilation or thrombolysis.

  • Percutaneous Angioscopy of saphenous vein coronary bypass grafts
    Journal of the American College of Cardiology, 1993
    Co-Authors: Christopher J. White, Stephen R. Ramee, Tyrone J. Collins, Juan E. Mesa, Ashit Jain
    Abstract:

    Objectives. We compared the results of percutaneous Angioscopy and angiography for detecting critical elements of surface lesion morphology in 21 patients undergoing balloon angioplasty of saphenous vein coronary bypass grafts. Background. Angiography remains the standard for diagnosing and treating intravascular pathology associated with atherosclerotic coronary artery disease. It has been demonstrated that coronary Angioscopy is more sensitive for identifying more complex atherosclerotic plaques and intracoronary thrombi in native coronary arteries. Methods. Angioscopy and angiography were performed before and after angioplasty of “culprit lesions” in bypass grafts. All but one of the patients had unstable angina. The mean age of the saphenous vein coronary bypass grafts was 10.1 ± 2.4 years (range 5 to 15). Results. Restesosis at a prior angioptasty site was present in seven patients. Intravascalar thrombi were seen by Angioscopy in 15 (71%) of 21 versus 4 (19%) of 21 grafts by angiography (p < 0.001). Dissection was identified by angioscony in 14 (66%) of 21 versus 2 (9.5%) of 21 grafts by angiograpay (p < 0.01). The presence of friable plaque liung the Iumen surface of the vein graft was detected by Angioscopy in 11 (52%) of 21 versus 4 (19%) of 21 grafts by angiography (p < 0.05). There was no correlation between age of the bypass graft and the finding of friable plaque. Conclusions. We conclude that Angioscopy is superior to angiography for detecting complex lesion merphology ta bypass grafts and that the presence of friable plaque does not preclude an uncomplicated angioplasty procedure.

  • Percutaneous coronary Angioscopy: applications in interventional cardiology.
    Journal of interventional cardiology, 1993
    Co-Authors: Christopher J. White, Stephen R. Ramee, Tyrone J. Collins, Juan E. Mesa, Ashit Jain, Hector O. Ventura
    Abstract:

    We performed percutaneous coronary Angioscopy in 35 patients to study the surface morphology of coronary artery lesions. Twenty-five patients had Angioscopy performed in conjunction with PTCA, including 20 patients with de novo lesions (16 patients with unstable angina, four patients with stable angina), and five patients with restenosis lesions. Ten cardiac transplant patients had Angioscopy performed in conjunction with annual follow-up angiography in an attempt to identify accelerated atherosclerotic lesions. There were no complications of Angioscopy in any patient. There were no intracoronary thrombi seen either by angiography or Angioscopy in the stable angina patients. In the unstable angina group, angiography identified thrombus in 2 out of 16 (12.5%) versus 15 out of 16 (94%) (P < 0.001) with Angioscopy. Following angioplasty, dissections were seen angiographically in 7 out of 16 (44%) of patients versus 16 of 16 (100%) of the patients by Angioscopy (P < 0.01). Restenosis lesions were characterized by a white, fibrous appearance instead of the usual yellow color of primary atherosclerotic lesions. In the ten cardiac transplant patients, Angioscopy appeared to be more sensitive than angiography for the detection of atherosclerosis. Yellow (atherosclerotic) and white (fibrotic) plaques were seen in the transplant patients, which often were not detected by angiography. In summary, Angioscopy is an excellent tool for visualizing the surface morphology of coronary artery lesions. The clinical indications for Angioscopy remain undefined at present. Possible applications for Angioscopy include intracoronary thrombolytic therapy, stratification of high risk angiographic results after angioplasty (“hazy” artery), and, finally, as an adjunct to interventional procedures such as stem implantation.

  • Percutaneous coronary Angioscopy during coronary angioplasty: clinical findings and implications
    Optical Fibers in Medicine VI, 1991
    Co-Authors: Stephen R. Ramee, Christopher J. White, Juan E. Mesa, Ashit Jain, Tyrone J. Collins
    Abstract:

    Percutaneous coronary Angioscopy was successfully performed with a steerable, balloon-tipped microangioscope in 36 of 43 patients undergoing percutaneous transluminal coronary angioplasty. The design of the device, technique of performing Angioscopy, reasons for failure to image successfully, Angioscopy findings, and clinical implications will be discussed.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Yasumi Uchida - One of the best experts on this subject based on the ideXlab platform.

  • Characterization of Coronary Fibrin Thrombus in Patients With Acute Coronary Syndrome Using
    2016
    Co-Authors: Dye-staining Angioscopy, Yasumi Uchida, Yasuto Uchida, Takeshi Sakurai, Masahito Kanai, Seiichiro Shirai, Toshihiro Morita
    Abstract:

    Objective—Because fibrin is transparent and almost invisible by any conventional imaging methodologies, clinical examinations of coronary fibrin thrombus have been ignored, and little is known about its role in the genesis of acute coronary syndrome (ACS). The present study was performed to visualize coronary fibrin thrombus and to examine its role in ACS. Methods and Results—Dye-staining coronary Angioscopy using Evans blue dye, which selectively stains fibrin blue but does not stain blood corpuscles, was performed for observation of globular coronary thrombi in 111 ACS patients. The thrombi were aspirated for histological examination. The thrombi were classified by visual appearance into 8 transparent, 3 light-red, 2 frosty glass–like and membranous, 32 white, 8 brown, 34 red, and 19 red-and-white in a mosaic pattern. Transparent thrombi that were not visible by conventional Angioscopy were visualized as a blue structure by dye-staining Angioscopy, and they were observed in patients with unstable angina (UA) and non-ST elevation myocardial infarction (NSTEMI). The thrombi caused total or subtotal coronary occlusion. The aspirated thrombi were composed of fibrin alone by histology. Fibrin-rich thrombi were visualized using dye-staining Angioscopy in 60 % of 50 patients with UANSTEMI and in 29 % of 61 patients with ST-elevation myocardial infarction. By histology of th

  • Dye-Staining Coronary Angioscopy and Cardioscopy
    Coronary Angioscopy, 2015
    Co-Authors: Takanobu Tomaru, Fumitaka Nakamura, Yoshiharu Fujimori, Yasumi Uchida
    Abstract:

    Coronary Angioscopy or cardioscopy using biocompatible markers is one choice for evaluation of tissues, cells, or molecules which comprise the target lesions. Angioscopy using EB as a biomarker, namely, dye-staining Angioscopy, has been developed and applied for molecular imaging of the substances that constitute atherosclerotic lesions.

  • characterization of coronary fibrin thrombus in patients with acute coronary syndrome using dye staining Angioscopy
    Arteriosclerosis Thrombosis and Vascular Biology, 2011
    Co-Authors: Yasumi Uchida, Yasuto Uchida, Takeshi Sakurai, Masahito Kanai, Seiichiro Shirai, Toshihiro Morita
    Abstract:

    Objective— Because fibrin is transparent and almost invisible by any conventional imaging methodologies, clinical examinations of coronary fibrin thrombus have been ignored, and little is known about its role in the genesis of acute coronary syndrome (ACS). The present study was performed to visualize coronary fibrin thrombus and to examine its role in ACS. Methods and Results— Dye-staining coronary Angioscopy using Evans blue dye, which selectively stains fibrin blue but does not stain blood corpuscles, was performed for observation of globular coronary thrombi in 111 ACS patients. The thrombi were aspirated for histological examination. The thrombi were classified by visual appearance into 8 transparent, 3 light-red, 2 frosty glass–like and membranous, 32 white, 8 brown, 34 red, and 19 red-and-white in a mosaic pattern. Transparent thrombi that were not visible by conventional Angioscopy were visualized as a blue structure by dye-staining Angioscopy, and they were observed in patients with unstable angina (UA) and non-ST elevation myocardial infarction (NSTEMI). The thrombi caused total or subtotal coronary occlusion. The aspirated thrombi were composed of fibrin alone by histology. Fibrin-rich thrombi were visualized using dye-staining Angioscopy in 60% of 50 patients with UA+NSTEMI and in 29% of 61 patients with ST-elevation myocardial infarction. By histology of the aspirated thrombi, fibrin-rich thrombi were observed in 71% of 33 patients with UA+NSTEMI and in 28% of 35 patients with ST-elevation myocardial infarction. Conclusion— Fibrin-rich coronary thrombi were frequently observed by both dye-staining Angioscopy and histology in ACS patients. Rarely, fibrin itself formed a globular thrombus and caused coronary occlusion.

  • Evaluation of Annuloaortic Ectasia by Angioscopy and IVUS "Report of 2 cases".
    Diagnostic and therapeutic endoscopy, 2000
    Co-Authors: Keiichi Tokuhiro, Yasumi Uchida, Kouhei Kawamura, Hiroshi Sakuragawa, Hiroshi Masuhara, Hidefumi Oosawa, Nobuya Koyama
    Abstract:

    We attempted combined use of Angioscopy and intravascular ultrasonography (IVUS) to localize the coronary ostia and determine the aortic segment to be replaced in patients with annuloaortic ectasia, because these preoperative informations are important for selection of an appropriate technique for reconstructing the coronary artery, to prevent complications, and also to postoperative follow-up. Two cases with annuloaortic ectasia underwent Angioscopy and IVUS both pre- and post-operatively. Structure of aortic cusps, position of coronary ostia, the extent of ectasia with very thin wall were clearly observed by IVUS. Angioscopy showed milky white luminal surface of the ectasic segment. After Cabrol’s operation, the sutured portion of native aorta and graft was clearly identified by IVUS and mural thrombus and naked surface of graft were observed by Angioscopy. Complications were observed in none. The results indicate feasibility of combined use of Angioscopy and IVUS for determination of surgical approach and follow-up in patients with AAE.

  • prediction of acute coronary syndromes by percutaneous coronary Angioscopy in patients with stable angina
    American Heart Journal, 1995
    Co-Authors: Yasumi Uchida, Fumitaka Nakamura, Takanobu Tomaru, Tomomitsu Oshima, Toshihiro Morita, Toshihiko Sasaki, Satoru Morizuki, Junichi Hirose
    Abstract:

    To pinpoint the link between plaque characteristics and acute coronary syndromes, we performed a 12-month prospective follow-up study in 157 patients with stable angina pectoris in whom regular coronary plaques were observed by percutaneous coronary Angioscopy. Acute coronary syndromes occurred more frequently in patients with yellow plaque than in those with white plaques (11 of 39 vs 4 of 118; p = 0.00021). Moreover, the syndromes occurred more frequently in patients with glistening yellow plaques than in those with nonglistening yellow plaques (9 of 13 vs 2 of 26; p = 0.00026). Thrombus arising from the ruptured identical plaques was confirmed by Angioscopy as the culprit lesion of the syndromes. The results indicate that acute coronary syndromes occur frequently and in a short time in patients with glistening yellow plaques and that Angioscopy but not angiography is feasible for prediction of the syndromes.

D R Campbell - One of the best experts on this subject based on the ideXlab platform.

  • Comparison of Angioscopy and angiography for monitoring infrainguinal bypass vein grafts: Results of a prospective randomized trial
    Journal of vascular surgery, 1993
    Co-Authors: A Miller, P A Stonebridge, G W Gibbons, F B Pomposelli, D V Freeman, Edward J. Marcaccio, Gary A. Tannenbaum, Christopher J. Kwolek, Philip T. Lavin, D R Campbell
    Abstract:

    Abstract Purpose:  This study was designed to determine whether, in primary infrainguinal bypass grafts in which only saphenous vein is used as the graft conduit, routine monitoring with intraoperative Angioscopy can improve early graft patency as compared with standard monitoring with intraoperative completion angiography; and to delineate the advantages and disadvantages of these two modalities and their respective roles for the routine monitoring of the infrainguinal bypass graft. Methods:  A total of 293 patients undergoing primary saphenous vein infrainguinal bypass grafting were prospectively randomized and monitored with either completion Angioscopy or completion angiography. Clinical parameters, indications for operation, graft anatomy, and configuration were evenly matched in both groups. Forty-three bypasses were excluded from the study after randomization, including 12 veins randomized to angiogram, deemed inferior, and prepared with Angioscopy. Results:  In the 250 bypass grafts (Angioscopy 128, angiography 122) there were 39 interventions (conduit, 29; anastomosis, 8; distal artery, 2), 32 with Angioscopy and 7 with angiography ( p p = 0.11 by one-sided hypothesis test). Conclusion:  Although no statistical improvement in the proportions of failures in primary saphenous vein bypass grafts routinely monitored with completion Angioscopy rather than the standard completion angiogram was demonstrated, the study delineates a trend that favors completion Angioscopy for routine vein graft monitoring and demonstrates the advantages of Angioscopy in preparing the optimal vein conduit. (J VASC SURG 1993;17:382-98.)

  • Continued experience with intraoperative Angioscopy for monitoring infrainguinal bypass grafting.
    Surgery, 1991
    Co-Authors: A Miller, P A Stonebridge, S J Jepsen, A Tsoukas, G W Gibbons, F B Pomposelli, D V Freeman, D R Campbell, F W Logerfo
    Abstract:

    Intraoperative Angioscopy provides direct, in vivo, three-dimensional visualization of the interior of the blood vessels and grafts. We have shown previously that with the application of the basic principles of irrigation and with a dedicated irrigation pump that routine intraoperative Angioscopy can be performed with consistent high quality results during lower extremity revascularization. In our total experience with Angioscopy as a monitoring procedure during infrainguinal bypass grafting, 259 intraoperative angioscopies, during 63 femoropopliteal and 196 distal bypass grafts, were performed from May 1, 1987, to October 31, 1989. Mean total irrigation fluid used in the study was 448 ml (range, 0 to 1400 ml) with good visual quality in more than 80% of the studies. The overall failure rate was 1.5%. No complications were directly attributable to the insertion of the angioscope or the use of the pump. Based on the angioscopic findings, 124 clinical or surgical decisions were made in 259 of the angioscopies. The incidence of graft failure in this study was 8.1% (less than 30 days) and 4.8% (greater than 30 days) with a mean follow-up of 272 days. Direct inspection of the interior of the graft and native vessels at the time of surgery has resulted in the recognition of previously unsuspected vein-graft pathology. Angioscopy as the sole monitoring procedure for infrainguinal bypass grafting is safe, effective, and reliable and may not only improve the durability of these grafts but may improve our understanding of the pathogenesis of graft failure and of the progression of the underlying atherosclerotic disease.

Tyrone J. Collins - One of the best experts on this subject based on the ideXlab platform.

  • Coronary Thrombi Increase PTCA Risk Angioscopy as a Clinical Tool
    Circulation, 1996
    Co-Authors: Christopher J. White, Stephen R. Ramee, Tyrone J. Collins, Richard R. Heuser, Alvaro Escobar, Arun K. Karsan, Dinesh Shaw, Suresh P. Jain, Theodore A. Bass, Paul S. Teirstein
    Abstract:

    Background The presence of angiographically identified intracoronary thrombus has been variably associated with complications after coronary angioplasty. Angiography has been shown to be less sensitive than Angioscopy for detecting subtle details of intracoronary morphology, such as intracoronary thrombi. The clinical importance of thrombi detectable by Angioscopy but not by angiography is not known. Methods and Results Percutaneous coronary Angioscopy was performed in 122 patients undergoing conventional coronary balloon angioplasty (PTCA) at six medical centers. Unstable angina was present in 95 patients (78%) and stable angina in 27 (22%). Therapy was not guided by angioscopic findings, and no patient received thrombolytic therapy as an adjunct to angioplasty. Coronary thrombi were identified in 74 target lesions (61%) by Angioscopy versus only 24 (20%) by angiography. A major in-hospital complication (death, myocardial infarction, or emergency bypass surgery) occurred in 10 of 74 patients (14%) with a...

  • Coronary Angioscopy of abrupt occlusion after angioplasty
    Journal of the American College of Cardiology, 1995
    Co-Authors: Christopher J. White, Stephen R. Ramee, Tyrone J. Collins, Suresh Jain, Alvaro Escobar
    Abstract:

    Abstract Objectives. This study used Angioscopy to determine the specific cause of vessel occlusion after percutaneous transluminal coronary angioplasty and compared the angiographic and angioscopic lesion morphologies in this setting. Background. Occlusion of a dilated coronary artery is the major cause of morbidity and mortality after coronary angioplasty. Attempts to reopen occluded vessels are either empirically guided or directed by angiography, which has inherent limitations. Angioscopy, the in vivo direct visualization of the endovascular surface, is potentially a more accurate means of identifying the cause of vessel occlusion after angioplasty. Methods. Percutaneous coronary Angioscopy was performed in 17 patients (17 vessels) after angiographic confirmation of postangioplasty vessel occlusion. Results. Angioscopy demonstrated the primary cause of the postangioplasty occlusion to be dissection in 14 patients (82%) and intracoronary thrombi in 3 (18%). Compared with Angioscopy, angiography was significantly less accurate in identifying the specific cause of the occlusion and correctly identified the cause of vessel occlusion in only 5 (29%) of 17 patients (p Conclusions. Angioscopy specifically identified the cause of occlusion in every patient, with coronary dissection the predominant cause of abrupt occlusion after coronary angioplasty. However, angiography was unable to identifiy a specific cause for vessel occlusion in the majority of our patients. Angioscopy may therefore prove useful in selecting specific treatment strategies for patients with abrupt occlusion after angioplasty, such as stent placement, atherectomy, repeat dilation or thrombolysis.

  • Percutaneous Angioscopy of saphenous vein coronary bypass grafts
    Journal of the American College of Cardiology, 1993
    Co-Authors: Christopher J. White, Stephen R. Ramee, Tyrone J. Collins, Juan E. Mesa, Ashit Jain
    Abstract:

    Objectives. We compared the results of percutaneous Angioscopy and angiography for detecting critical elements of surface lesion morphology in 21 patients undergoing balloon angioplasty of saphenous vein coronary bypass grafts. Background. Angiography remains the standard for diagnosing and treating intravascular pathology associated with atherosclerotic coronary artery disease. It has been demonstrated that coronary Angioscopy is more sensitive for identifying more complex atherosclerotic plaques and intracoronary thrombi in native coronary arteries. Methods. Angioscopy and angiography were performed before and after angioplasty of “culprit lesions” in bypass grafts. All but one of the patients had unstable angina. The mean age of the saphenous vein coronary bypass grafts was 10.1 ± 2.4 years (range 5 to 15). Results. Restesosis at a prior angioptasty site was present in seven patients. Intravascalar thrombi were seen by Angioscopy in 15 (71%) of 21 versus 4 (19%) of 21 grafts by angiography (p < 0.001). Dissection was identified by angioscony in 14 (66%) of 21 versus 2 (9.5%) of 21 grafts by angiograpay (p < 0.01). The presence of friable plaque liung the Iumen surface of the vein graft was detected by Angioscopy in 11 (52%) of 21 versus 4 (19%) of 21 grafts by angiography (p < 0.05). There was no correlation between age of the bypass graft and the finding of friable plaque. Conclusions. We conclude that Angioscopy is superior to angiography for detecting complex lesion merphology ta bypass grafts and that the presence of friable plaque does not preclude an uncomplicated angioplasty procedure.

  • Percutaneous coronary Angioscopy: applications in interventional cardiology.
    Journal of interventional cardiology, 1993
    Co-Authors: Christopher J. White, Stephen R. Ramee, Tyrone J. Collins, Juan E. Mesa, Ashit Jain, Hector O. Ventura
    Abstract:

    We performed percutaneous coronary Angioscopy in 35 patients to study the surface morphology of coronary artery lesions. Twenty-five patients had Angioscopy performed in conjunction with PTCA, including 20 patients with de novo lesions (16 patients with unstable angina, four patients with stable angina), and five patients with restenosis lesions. Ten cardiac transplant patients had Angioscopy performed in conjunction with annual follow-up angiography in an attempt to identify accelerated atherosclerotic lesions. There were no complications of Angioscopy in any patient. There were no intracoronary thrombi seen either by angiography or Angioscopy in the stable angina patients. In the unstable angina group, angiography identified thrombus in 2 out of 16 (12.5%) versus 15 out of 16 (94%) (P < 0.001) with Angioscopy. Following angioplasty, dissections were seen angiographically in 7 out of 16 (44%) of patients versus 16 of 16 (100%) of the patients by Angioscopy (P < 0.01). Restenosis lesions were characterized by a white, fibrous appearance instead of the usual yellow color of primary atherosclerotic lesions. In the ten cardiac transplant patients, Angioscopy appeared to be more sensitive than angiography for the detection of atherosclerosis. Yellow (atherosclerotic) and white (fibrotic) plaques were seen in the transplant patients, which often were not detected by angiography. In summary, Angioscopy is an excellent tool for visualizing the surface morphology of coronary artery lesions. The clinical indications for Angioscopy remain undefined at present. Possible applications for Angioscopy include intracoronary thrombolytic therapy, stratification of high risk angiographic results after angioplasty (“hazy” artery), and, finally, as an adjunct to interventional procedures such as stem implantation.

  • Percutaneous coronary Angioscopy during coronary angioplasty: clinical findings and implications
    Optical Fibers in Medicine VI, 1991
    Co-Authors: Stephen R. Ramee, Christopher J. White, Juan E. Mesa, Ashit Jain, Tyrone J. Collins
    Abstract:

    Percutaneous coronary Angioscopy was successfully performed with a steerable, balloon-tipped microangioscope in 36 of 43 patients undergoing percutaneous transluminal coronary angioplasty. The design of the device, technique of performing Angioscopy, reasons for failure to image successfully, Angioscopy findings, and clinical implications will be discussed.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Stephen R. Ramee - One of the best experts on this subject based on the ideXlab platform.

  • Coronary Thrombi Increase PTCA Risk Angioscopy as a Clinical Tool
    Circulation, 1996
    Co-Authors: Christopher J. White, Stephen R. Ramee, Tyrone J. Collins, Richard R. Heuser, Alvaro Escobar, Arun K. Karsan, Dinesh Shaw, Suresh P. Jain, Theodore A. Bass, Paul S. Teirstein
    Abstract:

    Background The presence of angiographically identified intracoronary thrombus has been variably associated with complications after coronary angioplasty. Angiography has been shown to be less sensitive than Angioscopy for detecting subtle details of intracoronary morphology, such as intracoronary thrombi. The clinical importance of thrombi detectable by Angioscopy but not by angiography is not known. Methods and Results Percutaneous coronary Angioscopy was performed in 122 patients undergoing conventional coronary balloon angioplasty (PTCA) at six medical centers. Unstable angina was present in 95 patients (78%) and stable angina in 27 (22%). Therapy was not guided by angioscopic findings, and no patient received thrombolytic therapy as an adjunct to angioplasty. Coronary thrombi were identified in 74 target lesions (61%) by Angioscopy versus only 24 (20%) by angiography. A major in-hospital complication (death, myocardial infarction, or emergency bypass surgery) occurred in 10 of 74 patients (14%) with a...

  • Coronary Angioscopy of abrupt occlusion after angioplasty
    Journal of the American College of Cardiology, 1995
    Co-Authors: Christopher J. White, Stephen R. Ramee, Tyrone J. Collins, Suresh Jain, Alvaro Escobar
    Abstract:

    Abstract Objectives. This study used Angioscopy to determine the specific cause of vessel occlusion after percutaneous transluminal coronary angioplasty and compared the angiographic and angioscopic lesion morphologies in this setting. Background. Occlusion of a dilated coronary artery is the major cause of morbidity and mortality after coronary angioplasty. Attempts to reopen occluded vessels are either empirically guided or directed by angiography, which has inherent limitations. Angioscopy, the in vivo direct visualization of the endovascular surface, is potentially a more accurate means of identifying the cause of vessel occlusion after angioplasty. Methods. Percutaneous coronary Angioscopy was performed in 17 patients (17 vessels) after angiographic confirmation of postangioplasty vessel occlusion. Results. Angioscopy demonstrated the primary cause of the postangioplasty occlusion to be dissection in 14 patients (82%) and intracoronary thrombi in 3 (18%). Compared with Angioscopy, angiography was significantly less accurate in identifying the specific cause of the occlusion and correctly identified the cause of vessel occlusion in only 5 (29%) of 17 patients (p Conclusions. Angioscopy specifically identified the cause of occlusion in every patient, with coronary dissection the predominant cause of abrupt occlusion after coronary angioplasty. However, angiography was unable to identifiy a specific cause for vessel occlusion in the majority of our patients. Angioscopy may therefore prove useful in selecting specific treatment strategies for patients with abrupt occlusion after angioplasty, such as stent placement, atherectomy, repeat dilation or thrombolysis.

  • Percutaneous Angioscopy of saphenous vein coronary bypass grafts
    Journal of the American College of Cardiology, 1993
    Co-Authors: Christopher J. White, Stephen R. Ramee, Tyrone J. Collins, Juan E. Mesa, Ashit Jain
    Abstract:

    Objectives. We compared the results of percutaneous Angioscopy and angiography for detecting critical elements of surface lesion morphology in 21 patients undergoing balloon angioplasty of saphenous vein coronary bypass grafts. Background. Angiography remains the standard for diagnosing and treating intravascular pathology associated with atherosclerotic coronary artery disease. It has been demonstrated that coronary Angioscopy is more sensitive for identifying more complex atherosclerotic plaques and intracoronary thrombi in native coronary arteries. Methods. Angioscopy and angiography were performed before and after angioplasty of “culprit lesions” in bypass grafts. All but one of the patients had unstable angina. The mean age of the saphenous vein coronary bypass grafts was 10.1 ± 2.4 years (range 5 to 15). Results. Restesosis at a prior angioptasty site was present in seven patients. Intravascalar thrombi were seen by Angioscopy in 15 (71%) of 21 versus 4 (19%) of 21 grafts by angiography (p < 0.001). Dissection was identified by angioscony in 14 (66%) of 21 versus 2 (9.5%) of 21 grafts by angiograpay (p < 0.01). The presence of friable plaque liung the Iumen surface of the vein graft was detected by Angioscopy in 11 (52%) of 21 versus 4 (19%) of 21 grafts by angiography (p < 0.05). There was no correlation between age of the bypass graft and the finding of friable plaque. Conclusions. We conclude that Angioscopy is superior to angiography for detecting complex lesion merphology ta bypass grafts and that the presence of friable plaque does not preclude an uncomplicated angioplasty procedure.

  • Percutaneous coronary Angioscopy: applications in interventional cardiology.
    Journal of interventional cardiology, 1993
    Co-Authors: Christopher J. White, Stephen R. Ramee, Tyrone J. Collins, Juan E. Mesa, Ashit Jain, Hector O. Ventura
    Abstract:

    We performed percutaneous coronary Angioscopy in 35 patients to study the surface morphology of coronary artery lesions. Twenty-five patients had Angioscopy performed in conjunction with PTCA, including 20 patients with de novo lesions (16 patients with unstable angina, four patients with stable angina), and five patients with restenosis lesions. Ten cardiac transplant patients had Angioscopy performed in conjunction with annual follow-up angiography in an attempt to identify accelerated atherosclerotic lesions. There were no complications of Angioscopy in any patient. There were no intracoronary thrombi seen either by angiography or Angioscopy in the stable angina patients. In the unstable angina group, angiography identified thrombus in 2 out of 16 (12.5%) versus 15 out of 16 (94%) (P < 0.001) with Angioscopy. Following angioplasty, dissections were seen angiographically in 7 out of 16 (44%) of patients versus 16 of 16 (100%) of the patients by Angioscopy (P < 0.01). Restenosis lesions were characterized by a white, fibrous appearance instead of the usual yellow color of primary atherosclerotic lesions. In the ten cardiac transplant patients, Angioscopy appeared to be more sensitive than angiography for the detection of atherosclerosis. Yellow (atherosclerotic) and white (fibrotic) plaques were seen in the transplant patients, which often were not detected by angiography. In summary, Angioscopy is an excellent tool for visualizing the surface morphology of coronary artery lesions. The clinical indications for Angioscopy remain undefined at present. Possible applications for Angioscopy include intracoronary thrombolytic therapy, stratification of high risk angiographic results after angioplasty (“hazy” artery), and, finally, as an adjunct to interventional procedures such as stem implantation.

  • Percutaneous coronary Angioscopy during coronary angioplasty: clinical findings and implications
    Optical Fibers in Medicine VI, 1991
    Co-Authors: Stephen R. Ramee, Christopher J. White, Juan E. Mesa, Ashit Jain, Tyrone J. Collins
    Abstract:

    Percutaneous coronary Angioscopy was successfully performed with a steerable, balloon-tipped microangioscope in 36 of 43 patients undergoing percutaneous transluminal coronary angioplasty. The design of the device, technique of performing Angioscopy, reasons for failure to image successfully, Angioscopy findings, and clinical implications will be discussed.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.