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Martin B Leon - One of the best experts on this subject based on the ideXlab platform.
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intravascular ultrasound assessment of the relation between early and late changes in arterial area and neointimal hyperplasia after percutaneous Transluminal Coronary Angioplasty and directional Coronary atherectomy
American Journal of Cardiology, 1999Co-Authors: Gary S Mintz, Takeshi Kimura, Masakiyo Nobuyoshi, Martin B LeonAbstract:Abstract Previous serial intravascular ultrasound (IVUS) analysis after percutaneous Transluminal Coronary Angioplasty or directional Coronary atherectomy showed (1) early (within 1 month) increase in arterial area, (2) late (1- to 6-month) decrease in arterial area, and (3) an increase in plaque area from immediately to 6 months after intervention. To further understand these findings, we used serial IVUS to study the relations between changes in arterial and plaque area during the follow-up period after Coronary intervention. Serial IVUS was performed before intervention and immediately, 24 hours, 1 month, and 6 months after percutaneous Transluminal Coronary Angioplasty (n = 35) or directional Coronary atherectomy (n = 26) in 57 patients. Arterial, lumen, and plaque areas were measured at the lesion site with the smallest preintervention and follow-up lumen areas at all time points. The increase in plaque area in the first month after intervention was accompanied by an equal or greater increase in arterial area (r = 0.670, p
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clinical intravascular ultrasound and quantitative angiographic determinants of the Coronary flow reserve before and after percutaneous Transluminal Coronary Angioplasty
American Journal of Cardiology, 1998Co-Authors: Alexandre Abizaid, Kenneth M Kent, Gary S Mintz, Augusto D Pichard, Lowell F Satler, Jeffrey J Popma, Carol Walsh, Martin B LeonAbstract:This study evaluated the clinical, intravascular ultrasound (IVUS), and angiographic determinants of the Coronary flow reserve (CFR) as measured by guidewire Doppler velocimetry. Using standard methodology, 86 consecutive patients were studied before intervention (n = 73 patients, including the assessment of intermediate stenoses) and/or after intervention (n = 39 patients, including after percutaneous Transluminal Coronary Angioplasty (PTCA) in 27 and post-Palmaz-Schatz stent placement + high-pressure adjunct PTCA in 12). Only 5 patients were studied before intervention, post-PTCA, and poststent. Univariate and multivariate clinical, quantitative Coronary angiography (QCA), and IVUS correlates of the CFR were evaluated. There was a linear relation between CFR and IVUS minimum lumen cross-sectional area (CSA): r = 0.771, p or = 4.0 mm2 had a diagnostic accuracy of 89% in identifying a CFR of > or = 2.0. This diagnostic accuracy increased slightly to 92% when only the preintervention observations were considered. Using multivariate linear regression analysis, the independent determinants of the CFR in the overall cohort of 112 observations were IVUS minimum lumen CSA (p or = 4.0 mm2 has a high diagnostic accuracy in predicting a CFR > or = 2.0, especially before intervention.
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axial plaque redistribution as a mechanism of percutaneous Transluminal Coronary Angioplasty
American Journal of Cardiology, 1996Co-Authors: Gary S Mintz, Kenneth M Kent, Augusto D Pichard, Lowell F Satler, Jeffrey J Popma, Martin B LeonAbstract:Abstract Plaque compression does not appear to be a mechanism of percutaneous Transluminal Coronary Angioplasty. Lumen enlargement is the result of combined plaque dissection, arterial expansion (presumably, limited by media-adventitial elasticity), and plaque redistribution, just like “footprints in the sand.”
Patrick W. Serruys - One of the best experts on this subject based on the ideXlab platform.
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Normalization of Coronary Flow Reserve by Percutaneous Transluminal Coronary Angioplasty
2016Co-Authors: Felix Zijlstra, Johan C. Reiber, Yves Juilliere, Patrick W. SerruysAbstract:Fifteen patients undergoing routine follow-up angiog-raphy 5 months after successful percutaneous translumtnal Coronary Angioplasty (PTCA) wtthout angina and with normal exercise thallium scinttgra-phy were selected for analysts. The Coronary flow reserves of these patients were compared with those of 24 patients with angiographkally normal Coronary arteries to establish whether PTCA can re-store to normal the Coronary flow reserve of pa-tknts with chronic Coronary artery disease. The quantitattve cineangiographk changes and the con-comitant alterations in Coronary flow reserve as an immediate result of the PTCA and the subsequent changes 5 months later are described. Coronary S ince the introduction of percutaneous Transluminal Coronary Angioplasty (PTCA) in 1977,l this procedure has gained increasing importance in the treatment of Coronary artery obstructions. The immediate and,long-term results of PTCA are usually assessed by Coronary angiography. Recently, the measurement of Coronary flow reserve has been proposed as a better method of evaluating the hemodynamic repercussions of coro-nary artery obstructions. 2~3 Three techniques have been developed that allow the measurement of region-al Coronary flow reserve during cardiac catheteriza-tion. The first uses a pulsed Doppler Coronary artery catheter that can measure intraCoronary blood flow velocity.4 The second technique is based on the radio-graphic assessment of myocardial perfusion using con-trast medium.5,6 The third technique is an indica-tor dilution technique with a platinum-tipped PTCA guidewire, using hydrogen as the indicator. ’ Although PTCA has been shown to result in symptomatic, hemo-dynamic and functional improvement,8-10 doubt ha
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quantitative assessment with intraCoronary ultrasound of the mechanisms of restenosis after percutaneous Transluminal Coronary Angioplasty and directional Coronary atherectomy
American Journal of Cardiology, 1995Co-Authors: Carlo Di Mario, P. J. De Feyter, Robert J Gil, Edoardo Camenzind, Yukio Ozaki, Clemens Von Birgelen, Victor A Umans, Peter De Jaegere, Jos R T C Roelandt, Patrick W. SerruysAbstract:The mechanisms of immediate and late changes after percutaneous Transluminal Coronary Angioplasty (PTCA) and directional Coronary atherectomy (DCA) were assessed by serial ultrasound imaging in 18 patients treated with PTCA and 16 treated with DCA before, immediately after, and 6 months after Coronary interventions. A reduction in plaque area was the main operative mechanism of DCA, explaining 66% of lumen enlargement. In the PTCA group, the increase in lumen area was the result of a more balanced combination of plaque reduction (52% of lumen increase) and increase in total lumen area (48%); p < 0.05 versus DCA. In the PTCA group, this last mechanism was prevalent (p < 0.05) in the lesions showing wall fracture or dissection after treatment and in the lesions with a mixed or calcific composition. In the PTCA group, concentric lesions showed a greater plaque compression than eccentric lesions (p < 0.02). Plaque increase was responsible for 92% and 32% of the late lumen loss after DCA and after PTCA, respectively (p < 0.05). In PTCA patients, a chronic reduction in total vessel area was the main operative mechanism of lumen reduction (67%) and was prevalent in lesions with a mixed or calcific composition (p < 0.05).
Eric J Topol - One of the best experts on this subject based on the ideXlab platform.
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a comparison of ionic versus nonionic contrast medium during primary percutaneous Transluminal Coronary Angioplasty for acute myocardial infarction gusto iib
American Journal of Cardiology, 2000Co-Authors: Wayne Batchelor, Stephen G Ellis, Eric J Topol, Harry R Phillips, Christopher B Granger, Neil S Kleiman, Amadeo Betriu, Doug A Criger, Amanda Stebbins, Robert M CaliffAbstract:The clinical impact of contrast medium selection during primary percutaneous Transluminal Coronary Angioplasty for acute myocardial infarction (AMI) has not been studied. We compared the clinical outcomes of patients who received ionic versus nonionic low osmolar contrast medium in the setting of primary percutaneous Transluminal Coronary Angioplasty for AMI in the second Global Use of Strategies to Open Occluded Coronary Arteries in Acute Coronary Syndromes (GUSTO IIb) trial. Univariable and multivariable analyses were performed to assess the relation between contrast medium selection and clinical outcome (death, reinfarction, or refractory ischemia) at 30 days. Although baseline clinical and angiographic characteristics were generally similar between the 2 groups, patients who received ionic, low osmolar contrast were less likely to have been enrolled at a US site (23% vs 43%, p = 0.001) and less likely to have occlusion of the left anterior descending Coronary artery (34% vs 47%, p = 0.03) or a history of prior AMI (8% vs 16%, p = 0.02). The triple composite end point of death, reinfarction, or refractory ischemia occurred less frequently in the ionic group, both in the hospital (4.4% vs 11%, p = 0.018) and at 30 days (5.5% vs 11%, p = 0.044). Although the trend favoring ionic contrast persisted, the differences were no longer statistically significant after adjustment for imbalances in baseline characteristics using a risk model developed from the study sample (n = 454, adjusted odds ratio for ionic contrast 0.48 [0.22 to 1.02], p = 0.055), and using a model developed from the entire GUSTO IIb study cohort (n = 12,142, adjusted odds ratio for ionic contrast 0.50 [0.23 to 1.06], p = 0.072). The results of this observational study warrant further elucidation by a randomized study design in this setting.
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cost efficacy modeling of catheter reuse for percutaneous Transluminal Coronary Angioplasty
Journal of the American College of Cardiology, 1996Co-Authors: Koon Hou Mak, Mark J Eisenberg, David S Eccleston, Kimberly J Brown, Stephen G Ellis, Eric J TopolAbstract:Abstract Objectives. Our goal was to provide the range of cost savings associated with various catheter reuse strategies. Background. Percutaneous Transluminal Coronary Angioplasty catheters are commonly reused in several countries outside the United States. However, the cost-effectiveness of such reuse strategies has not been evaluated. Methods. Three theoretical models of catheter reuse were constructed using the actual costs for treating patients with Coronary Angioplasty at the Cleveland Clinic. Costs were calculated based on the number of balloon catheters, the amount of contrast agent used and the rates for urgent revascularization that were observed in a prospective Canadian study on catheter reuse. Results. The median cost to treat a lesion by means of Coronary Angioplasty using new catheters was $8,800 per patient. In reuse models, the potential to reduce cost depended on the number of balloon catheters used and the rates of urgent revascularization. The “best case” scenario offered a potential savings of $480 (5.5% of total in-hospital cost), whereas the “worst case” scenario resulted in an increased cost of $1,075 (12.2% of total in-hospital cost) compared with the single-use strategy. Cost of the “likely case” scenario was similar to that of the single-use strategy. Sensitivity analyses identified the different rates of revascularization and cost of balloon catheters required to offset potential savings in each strategy. Conclusions. Although reusing Coronary Angioplasty catheters may reduce total in-hospital costs, even a modest increase in complications requiring urgent revascularization may offset any potential savings. However, if an increase in complications and procedure time can be avoided, the reuse strategy has significant economic potential and, ultimately, may be extended to other percutaneous Coronary interventional equipment.
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effect of platelet glycoprotein iib iiia integrin blockade on activated clotting time during percutaneous Transluminal Coronary Angioplasty or directional atherectomy the epic trial
American Journal of Cardiology, 1995Co-Authors: David J Moliterno, Robert M Califf, Frank V Aguirre, Keaven M Anderson, Kristina N Sigmon, Harlan F Weisman, Eric J TopolAbstract:Abstract The activated clotting time (ACT) has been used during percutaneous Transluminal Coronary Angioplasty (PTCA) to monitor the extent of thrombin inhibition and anti-coagulation from heparin in an attempt to minimize untoward thrombotic events and hemorrhagic complications. With the introduction of potent platelet inhibitors, such as the chimeric monoclonal antibody c7E3, to interventional cardiology, the utility of measuring and regulating procedural ACT has not been examined. To investigate the possible influence of platelet IIb/IIIa antagonism on procedural ACT, we reviewed data from the Evaluation of c7E3 Fab in the Prevention of Ischemic Complications (EPIC) trial. In the EPIC trial, 2,099 patients undergoing PTCA with a high risk of abrupt vessel closure were randomized to receive placebo (n = 696) or the IIb/IIIa platelet receptor antagonist c7E3 Fab (n = 1,403). Despite receiving less procedural heparin, and fewer patients receiving very high heparin doses (>14,000 U) than the placebo group, those receiving c7E3 had a higher mean (401 vs 367 seconds, p
Robert M Califf - One of the best experts on this subject based on the ideXlab platform.
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a comparison of ionic versus nonionic contrast medium during primary percutaneous Transluminal Coronary Angioplasty for acute myocardial infarction gusto iib
American Journal of Cardiology, 2000Co-Authors: Wayne Batchelor, Stephen G Ellis, Eric J Topol, Harry R Phillips, Christopher B Granger, Neil S Kleiman, Amadeo Betriu, Doug A Criger, Amanda Stebbins, Robert M CaliffAbstract:The clinical impact of contrast medium selection during primary percutaneous Transluminal Coronary Angioplasty for acute myocardial infarction (AMI) has not been studied. We compared the clinical outcomes of patients who received ionic versus nonionic low osmolar contrast medium in the setting of primary percutaneous Transluminal Coronary Angioplasty for AMI in the second Global Use of Strategies to Open Occluded Coronary Arteries in Acute Coronary Syndromes (GUSTO IIb) trial. Univariable and multivariable analyses were performed to assess the relation between contrast medium selection and clinical outcome (death, reinfarction, or refractory ischemia) at 30 days. Although baseline clinical and angiographic characteristics were generally similar between the 2 groups, patients who received ionic, low osmolar contrast were less likely to have been enrolled at a US site (23% vs 43%, p = 0.001) and less likely to have occlusion of the left anterior descending Coronary artery (34% vs 47%, p = 0.03) or a history of prior AMI (8% vs 16%, p = 0.02). The triple composite end point of death, reinfarction, or refractory ischemia occurred less frequently in the ionic group, both in the hospital (4.4% vs 11%, p = 0.018) and at 30 days (5.5% vs 11%, p = 0.044). Although the trend favoring ionic contrast persisted, the differences were no longer statistically significant after adjustment for imbalances in baseline characteristics using a risk model developed from the study sample (n = 454, adjusted odds ratio for ionic contrast 0.48 [0.22 to 1.02], p = 0.055), and using a model developed from the entire GUSTO IIb study cohort (n = 12,142, adjusted odds ratio for ionic contrast 0.50 [0.23 to 1.06], p = 0.072). The results of this observational study warrant further elucidation by a randomized study design in this setting.
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effect of platelet glycoprotein iib iiia integrin blockade on activated clotting time during percutaneous Transluminal Coronary Angioplasty or directional atherectomy the epic trial
American Journal of Cardiology, 1995Co-Authors: David J Moliterno, Robert M Califf, Frank V Aguirre, Keaven M Anderson, Kristina N Sigmon, Harlan F Weisman, Eric J TopolAbstract:Abstract The activated clotting time (ACT) has been used during percutaneous Transluminal Coronary Angioplasty (PTCA) to monitor the extent of thrombin inhibition and anti-coagulation from heparin in an attempt to minimize untoward thrombotic events and hemorrhagic complications. With the introduction of potent platelet inhibitors, such as the chimeric monoclonal antibody c7E3, to interventional cardiology, the utility of measuring and regulating procedural ACT has not been examined. To investigate the possible influence of platelet IIb/IIIa antagonism on procedural ACT, we reviewed data from the Evaluation of c7E3 Fab in the Prevention of Ischemic Complications (EPIC) trial. In the EPIC trial, 2,099 patients undergoing PTCA with a high risk of abrupt vessel closure were randomized to receive placebo (n = 696) or the IIb/IIIa platelet receptor antagonist c7E3 Fab (n = 1,403). Despite receiving less procedural heparin, and fewer patients receiving very high heparin doses (>14,000 U) than the placebo group, those receiving c7E3 had a higher mean (401 vs 367 seconds, p
K L Neuhaus - One of the best experts on this subject based on the ideXlab platform.
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direct percutaneous Transluminal Coronary Angioplasty in acute myocardial infarction predictors of short term outcome and the impact of Coronary stenting
European Heart Journal, 1998Co-Authors: A Vogt, Walter Niederer, C Pfafferott, H J Engel, K W Heinrich, W Merx, J Jehle, K L NeuhausAbstract:Background Direct percutaneous trans1umina1 Coronary Angioplasty (PTCA) is widely accepted in the treatment of acute myocardial infarction since excellent results had been reported from several small randomized trials, Less favourable results were observed in large-scale registries. In particular, the use of stents in acute myocardial infarction has become common practice without documented evidence of clinical efficacy. Methods Data were analysed from a registry of all consecutive percutaneous Transluminal Coronary Angioplasty procedures from 62 centres in Germany, including 2331 direct percutaneous Transluminal Coronary Angioplasty in acute myocardial infarction from July 1994 to April 1997. Results The overall angiographic success rate of percutaneous Transluminal Coronary Angioplasty, defined as complete antegrade perfusion of the infarct vessel, was 87%. In-hospital mortality was 11.2%. The most important predictor of death was the presence of cardiogenic shock in 15% of patients, of whom 52% died. Mortality in patients without shock was 3.9%. Failed percutaneous Transluminal Coronary Angioplasty was associated with a mortality of 36%. Further independent predictors of death were older age, multivessel disease, and anterior myocardial infarction. Stents were used in 4.1 % of the procedures in 1994, increasing to 53% in 1997. However, this was not accompanied by improved clinical outcome. Mortality with Coronary stenting was 9.9% vs 11.6% without stents (ns). Conclusions Direct percutaneous Transluminal Coronary Angioplasty is a valuable treatment strategy in acute myocardial infarction, although the results are less exceptional than reported from some highly specialized centres. Failed percutaneous Transluminal Coronary Angioplasty seems to be harmful, thus outweighing much of the benefit from successful procedures. Stents did not improve the clinical outcome significantly, despite technically successful placement in 98%. Mortality from cardiogenic shock continues to be excessively high despite direct PTCA.
