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Background: Quantitative myocardial PET perfusion imaging requires partial volume corrections.Methods: Patients underwent ECG-gated, rest-dipyridamole, myocardial perfusion PET using Rb-82 decay corrected in Bq/cc for diastolic, systolic, and combined whole cycle ungated images. Diastolic partial volume correction relative to systole was determined from the systolic/diastolic activity ratio, systolic partial volume correction from phantom dimensions comparable to systolic LV wall thicknesses and whole heart cycle partial volume correction for ungated images from fractional systolic-diastolic duration for systolic and diastolic partial volume corrections.Results: For 264 PET perfusion images from 159 patients (105 rest-stress image pairs, 54 individual rest or stress images), average resting diastolic partial volume correction relative to systole was 1.14 ± 0.04, independent of heart rate and within ±1.8% of stress images (1.16 ± 0.04). Diastolic partial volume corrections combined with those for phantom dimensions comparable to systolic LV wall thickness gave an average whole heart cycle partial volume correction for ungated images of 1.23 for Rb-82 compared to 1.14 if positron range were negligible as for F-18.Conclusion: Quantitative myocardial PET perfusion imaging requires partial volume correction, herein demonstrated clinically from systolic/diastolic absolute activity ratios combined with phantom data accounting for Rb-82 positron range. [ABSTRACT FROM AUTHOR]

Catheter-induced left main coronary artery dissection is quite rare. We describe two cases of iatrogenic left main coronary artery dissection. In the first case, the aortic root was involved in the dissection process, and stenting of the entry point did not halt the progression of dissection. In the second case, the dissection did not involve the aortic root. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this study was to determine if combined intense lifestyle and pharmacologic lipid treatment reduce myocardial perfusion abnormalities and coronary events in comparison to usual-care cholesterol-lowering drugs and whether perfusion changes predict outcomes.Background: Lifestyle and lipid drugs separately benefit patients with coronary artery disease (CAD).Methods: A total of 409 patients with CAD, who underwent myocardial perfusion imaging by dipyridamole positron emission tomography at baseline and after 2.6 years, had quantitative size/severity of perfusion defects measured objectively by automated software with follow-up for five additional years for coronary artery bypass graft, percutaneous coronary intervention, myocardial infarction, or cardiac death. Patients were categorized blindly according to prospective, predefined criteria as "poor" treatment without diet or lipid drugs, or smoking; "moderate" treatment on American Heart Association diet and lipid-lowering drugs or on strict low-fat diet (<10% of calories) without lipid drugs; and "maximal" treatment with diet <10% of calories as fat, regular exercise, and lipid active drugs dosed to target goals of low-density lipoproteins <2.3 mmol/l (90 mg/dl), high-density lipoproteins >1.2 mmol/l (45 mg/dl), and triglycerides <1.1 mmol/l (100 mg/dl).Results: Over five years, coronary events occurred in 6.6%, 20.3%, and 30.6% of patients on maximal, moderate, and poor treatment, respectively (p = 0.001). Size/severity of perfusion abnormalities significantly decreased for patients receiving maximal treatment and increased for patients undergoing moderate and poor treatment (p = 0.003 and 0.0001, respectively). Combined intense lifestyle change plus lipid active drugs and severity/change of perfusion abnormalities independently predicted cardiac events.Conclusions: Intense lifestyle and pharmacologic lipid treatment reduce size/severity of myocardial perfusion abnormalities and cardiac events compared with usual-care cholesterol-lowering drugs. Perfusion changes parallel treatment intensity and predict outcomes. [ABSTRACT FROM AUTHOR]

To map precise myocardial perfusion anatomy, we correlated detailed coronary arteriographic anatomy for every coronary artery and all secondary branches in the heart that had flow-limiting stenosis with corresponding specific, circumscribed, myocardial perfusion defects by positron emission tomography. Eight hundred ninety-five patients with abnormal coronary arteriograms showing any visible coronary artery narrowing of greater than 10% diameter stenosis underwent positron emission tomography perfusion imaging at rest and after dipyridamole stress; the data obtained were processed automatically into 3-dimensional topographic displays of relative radionuclide uptake in anterior, septal, left lateral, and inferior quadrant views, without attenuation artifacts, depth-dependent resolution, or spatial distortion of polar displays. The selection criterion for detailed anatomic analysis was the presence of a discrete, localized, moderate to severe, dipyridamole-induced perfusion defect, defined by automated algorithms as 1 quadrant view outside 2 SDs of healthy control subjects with which a specific stenotic coronary artery and/or its secondary branches could be correlated unequivocally on the coronary arteriogram for mapping precise perfusion anatomy, not for determining sensitivity or specificity. Because the anatomy of myocardial perfusion is inherently not statistical data, the results are presented as a summary atlas and series of individual cases that illustrate myocardial perfusion anatomy. Because the patterns of myocardial perfusion anatomy were derived from a large number of subjects, the atlas provides generalized information, not previously published, that correlates detailed arteriographic anatomy with perfusion anatomy including secondary diagonal, marginal, and posterior descending branches of the coronary arteries. [ABSTRACT FROM AUTHOR]

Discusses effects of Clopidogrel pretreatment before percutaneous coronary intervention in patients treated with glycoprotein IIb/IIIa inhibitors, abciximab of tirofiban. Major adverse cardiac event; Adverse effects of therapy; Major clinical goal of antithrombotic therapy.

Acute reintervention was performed in 26 of 1,620 patients after coronary stenting (1.6%). Half of the patients had stent thrombosis and the other half residual anatomic problems. The mean time for reintervention was shorter in patients with stent thrombosis. All patients with stent thrombosis had a sudden recurrence of chest pain. Electrocardiographic changes were more common with stent thrombosis. Composite end point occurred in 10 patients (77%) with stent thrombosis versus 5 (39%) in the other group (p = 0.04). [ABSTRACT FROM AUTHOR]

Background and Aims: Coronary flow capacity (CFC) is associated with an observed 10-year survival probability for individual patients before and after actual revascularization for comparison to virtual hypothetical ideal complete revascularization., Methods: Stress myocardial perfusion (mL/min/g) and coronary flow reserve (CFR) per pixel were quantified in 6979 coronary artery disease (CAD) subjects using Rb-82 positron emission tomography (PET) for CFC maps of artery-specific size-severity abnormalities expressed as percent left ventricle with prospective follow-up to define survival probability per-decade as fraction of 1.0., Results: Severely reduced CFC in 6979 subjects predicted low survival probability that improved by 42% after revascularization compared with no revascularization for comparable severity (P = .0015). For 283 pre-and-post-procedure PET pairs, severely reduced regional CFC-associated survival probability improved heterogeneously after revascularization (P < .001), more so after bypass surgery than percutaneous coronary interventions (P < .001) but normalized in only 5.7%; non-severe baseline CFC or survival probability did not improve compared with severe CFC (P = .00001). Observed CFC-associated survival probability after actual revascularization was lower than virtual ideal hypothetical complete post-revascularization survival probability due to residual CAD or failed revascularization (P < .001) unrelated to gender or microvascular dysfunction. Severely reduced CFC in 2552 post-revascularization subjects associated with low survival probability also improved after repeat revascularization compared with no repeat procedures (P = .025)., Conclusions: Severely reduced CFC and associated observed survival probability improved after first and repeat revascularization compared with no revascularization for comparable CFC severity. Non-severe CFC showed no benefit. Discordance between observed actual and virtual hypothetical post-revascularization survival probability revealed residual CAD or failed revascularization., (© The Author(s) 2023. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Background: The literature reports no randomized trial in chronic coronary artery disease (CAD) of a comprehensive management strategy integrating intense lifestyle management, maximal medical treatment to specific goals and high precision quantitative cardiac positron emission tomography (PET) for identifying high mortality risk patients needing essential invasive procedures. We hypothesize that this comprehensive strategy achieves greater risk factor reduction, lower major adverse cardiovascular events and fewer invasive procedures than standard practice., Methods: The CENTURY Study (NCT00756379) is a randomized-controlled-trial study in patients with stable or at high risk for CAD. Patients are randomized to standard of care (Standard group) or intense comprehensive lifestyle-medical treatment to targets and PET guided interventions (Comprehensive group). Comprehensive Group patients are regularly consulted by the CENTURY team implementing diet/lifestyle/exercise program and medical treatment to target risk modification. Cardiac PET at baseline, 24-, and 60-months quantify the physiologic severity of CAD and guide interventions in the Comprehensive group while patients and referring physicians of the Standard group are blinded to PET results. The primary end-point is the CENTURY risk score reduction during 5 years follow-up. The secondary endpoint is a composite of death, non-fatal myocardial infarction, stroke, and coronary revascularization., Conclusions: The CENTURY Study is the first study in stable CAD to test the incremental benefit of a comprehensive strategy integrating intense lifestyle modification, medical treatment to specific goals, and high-precision quantitative myocardial perfusion imaging to guide revascularization. A total of 1028 patients have been randomized, and the 5 years follow-up will conclude in 2022., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Because randomized coronary revascularization trials in stable coronary artery disease (CAD) have shown no reduced myocardial infarction (MI) or mortality, the threshold of quantitative myocardial perfusion severity was analyzed for association with reduced death, MI, or stroke after revascularization within 90 d after PET. Methods: In a prospective long-term cohort of stable CAD, regional, artery-specific, quantitative myocardial perfusion by PET, coronary revascularization within 90 d after PET, and all-cause death, MI, and stroke (DMS) at 9-y follow-up (mean ± SD, 3.0 ± 2.3 y) were analyzed by multivariate Cox regression models and propensity analysis. Results: For 3,774 sequential rest-stress PET scans, regional, artery-specific, severely reduced coronary flow capacity (CFC) (coronary flow reserve ≤ 1.27 and stress perfusion ≤ 0.83 cc/min/g) associated with 60% increased hazard ratio for major adverse cardiovascular events and 30% increased hazard of DMS that was significantly reduced by 54% associated with revascularization within 90 d after PET ( P = 0.0369), compared with moderate or mild CFC, coronary flow reserve, other PET metrics or medical treatment alone. Depending on severity threshold for statistical certainty, up to 19% of this clinical cohort had CFC severity associated with reduced DMS after revascularization. Conclusion: CFC by PET provides objective, regional, artery-specific, size-severity physiologic quantification of CAD severity associated with high risk of DMS that is significantly reduced after revascularization within 90 d after PET, an association not seen for moderate to mild perfusion abnormalities or medical treatment alone., (© 2019 by the Society of Nuclear Medicine and Molecular Imaging.)

Unlabelled: SPECT and PET myocardial perfusion images show greater myocardial intensity and homogeneity in systole than diastole because of greater systolic myocardial thickness, less partial volume loss, and enhanced activity recovery. Consequently, conventional myocardial perfusion images obtained from whole cardiac cycles have lower myocardial intensity and greater heterogeneity than systolic images. Considering relative activity distribution on SPECT systolic images may add clinical utility to whole-cycle images and wall motion., Methods: Patients undergoing coronary angiogram within 4 mo after SPECT myocardial perfusion imaging were reviewed. Images were interpreted by 2 masked interpreters using a 17-segment, 5-point scale to determine summed rest scores (SSS), summed stress scores, and summed difference scores on conventional and systolic images in 603 patients (55.6% no coronary artery disease [no-CAD] and 44.4% CAD). Studies were considered normal when the SSS was less than 4 and summed difference score was less than 2., Results: In the no-CAD group, systolic SSS was lower than SSS from conventional images (2 ± 2.3 vs. 3 ± 2.6, P < 0.001). In contrast, SSS derived from systolic and conventional images were not different in the obstructive CAD group (9.1 ± 7.6 vs. 9.2 ± 7.4, P = 0.559). When systolic images were considered, true-negative studies increased from 27.2% to 43.3% (P < 0.001) whereas false-positive studies decreased from 28.4% to 12.3% (P < 0.001). True-positive (38% vs. 37.2%, P = 0.505) and false-negative studies (6.5% vs. 7%, P = 0.450) were not significantly changed. Diagnostic accuracy increased from 65.2% to 80.8% (P < 0.001)., Conclusion: For gated SPECT myocardial perfusion imaging, when relative activity distribution on systolic images was considered, false-positive studies were reduced and diagnostic accuracy was improved., (© 2015 by the Society of Nuclear Medicine and Molecular Imaging, Inc.)

A coordinated system of care for patients with ST-segment elevation myocardial infarctions that includes prehospital administration of reduced-dose fibrinolytic agents coupled with urgent percutaneous coronary intervention (PCI), termed FAST-PCI, has been shown to be at least as effective as primary PCI (PPCI) alone. However, this reduced-dose fibrinolytic strategy could be associated with increased bleeding risk, especially in elderly patients. The purpose of this study was to examine 30-day outcomes in patients aged ≥75 years with ST-segment elevation myocardial infarctions treated with either strategy. Data from 120 patients aged ≥75 years treated with FAST-PCI were compared with those of 94 patients aged ≥75 years treated with PPCI. The primary comparator was mortality at 30 days. Stroke, reinfarction, and major bleeding were also compared. The groups were well matched for age, cardiac risk factors, and ischemic times. At 30 days, mortality was lower with FAST-PCI than with PPCI (4.2% vs 18.1%, p <0.01). Rates of stroke, reinfarction, and major bleeding (4% vs 2%) were similar in the 2 groups. The FAST-PCI cohort had lower rates of cardiogenic shock on hospital arrival (15% vs 26%, p = 0.05) and completely occluded infarct arteries (Thrombolysis In Myocardial Infarction [TIMI] grade 0 flow, 35% vs 61%, p <0.01). In conclusion, for patients aged ≥75 years with ST-segment elevation myocardial infarctions, a FAST-PCI strategy in a coordinated system of care was associated with reduced 30-day mortality, earlier infarct artery patency, and lower incidence of cardiogenic shock at arrival compared with PPCI, without apparent bleeding, stroke, or reinfarction penalties., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Unlabelled: We present a preliminary cost analysis of a combination intervention using PET and comprehensive lifestyle modification to reverse atherosclerosis. With a sensitivity of 92%-95% and specificity of 85%-95%, PET is an essential tool for high-precision diagnosis of coronary artery disease, accurately guiding optimal treatment for both symptomatic and asymptomatic patients. PET imaging provides a powerful visual and educational aid for helping patients identify and adopt appropriate treatments. However, little is known about the operational cost of using the technology for this purpose., Methods: The analysis was done in the context of the Century Health Study for Cardiovascular Medicine (Century Trial), a 1,300-patient, randomized study combining PET imaging with lifestyle changes. Our methodology included a microcosting and time study focusing on estimating average direct and indirect costs., Results: The total cost of the Century Trial in present-value terms is $9.2 million, which is equal to $7,058 per patient. Sensitivity analysis indicates that the present value of total costs is likely to range between $8.8 and $9.7 million, which is equivalent to $6,655-$7,606 per patient., Conclusion: The clinical relevance of the Century Trial is significant since it is, to our knowledge, the first randomized controlled trial to combine high-precision imaging with lifestyle strategies. The Century Trial is in its second year of a 5-y protocol, and we present preliminary findings. The results of this cost study, however, provide policy makers with an early estimate of the costs of implementing, at large scale, a combined intervention such as the Century Trial. Further, we believe that imaging-guided lifestyle management may have considerable potential for improving outcomes and reducing health-care costs by eliminating unnecessary invasive procedures.

Angiographic severity of coronary artery stenosis has historically been the primary guide to revascularization or medical management of coronary artery disease. However, physiologic severity defined by coronary pressure and/or flow has resurged into clinical prominence as a potential, fundamental change from anatomically to physiologically guided management. This review addresses clinical coronary physiology-pressure and flow-as clinical tools for treating patients. We clarify the basic concepts that hold true for whatever technology measures coronary physiology directly and reliably, here focusing on positron emission tomography and its interplay with intracoronary measurements., (Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

In patients with acute ST-elevation myocardial infarction (STEMI), a strategy of prehospital reduced dose fibrinolytic administration coupled with urgent percutaneous coronary intervention (PCI), termed FAST-PCI strategy, has been found to be superior to primary PCI (PPCI) alone. A coordinated STEMI system of care that includes FAST-PCI should offer better outcomes than a system in which prehospital diagnosis of STEMI is followed by PPCI alone. The aim of this study was to compare the in-hospital outcomes for patients treated with the FAST-PCI approach with outcomes for patients treated with the PPCI approach in a common system. The in-hospital data for 253 STEMI patients (March 2003-December 2009) treated with a FAST-PCI protocol were compared with 124 patients (January 2010-August 2011) treated with PPCI strategy alone. In-hospital mortality was the primary comparator. Stroke, major bleeding, and reinfarction during index hospitalization were also compared. The in-hospital mortality was significantly lower with FAST-PCI than with PPCI (2.77% vs 10.48%, p = 0.0017). Rates of stroke, reinfarction, and major bleeding were similar in the 2 groups. There was a lower frequency of pre-PCI Thrombolysis In Myocardial Infarction 0 flow (no patency) seen in patients treated with FAST-PCI compared with the PPCI patients (26.7% vs 62.7%, p <0.0001). Earlier infarct artery patency in the FAST-PCI group had a favorable impact on the incidence of cardiogenic shock on hospital arrival (3.1% vs 20.9%, p <0.0001). In conclusion, compared with a PPCI strategy in a common STEMI system of care, the FAST-PCI strategy was associated with earlier infarct artery patency and lower incidence of cardiogenic shock, as well as with reduced in-hospital mortality., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Introduction: Acute anterior myocardial infarctions caused by proximal left anterior descending (LAD) artery occlusions are associated with a higher morbidity and mortality. Early identification of high-risk patients via the 12-lead electrocardiogram (ECG) could assist physicians and emergency response teams in providing early and aggressive care for patients with anterior ST-elevation myocardial infarctions (STEMI). Approximately 25% of US hospitals have primary percutaneous coronary intervention (PCI) capability for the treatment of acute myocardial infarctions. Given the paucity of hospitals capable of PCI, early identification of more severe myocardial infarction may prompt emergency medical service routing of these patients to PCI-capable hospitals. We sought to determine if the 12 lead ECG is capable of predicting proximal LAD artery occlusions., Methods: In a retrospective, post-hoc analysis of the Pre-Hospital Administration of Thrombolytic Therapy with Urgent Culprit Artery Revascularization pilot trial, we compared the ECG findings of proximal and nonproximal LAD occlusions for patients who had undergone an ECG within 180 minutes of symptom onset., Results: In this study, 72 patients had anterior STEMIs, with ECGs performed within 180 minutes of symptom onset. In patients who had undergone ECGs within 60 minutes (n = 35), the mean sum of ST elevation (STE) in leads V1 through V6 plus ST depression (STD) in leads II, III, and aVF was 19.2 mm for proximal LAD occlusions and 11.7 mm for nonproximal LAD occlusions (P = 0.007). A sum STE in V1 through V6 plus STD in II, III, and aVF of at least 17.5 mm had a sensitivity of 52.3%, specificity of 92.9%, positive predictive value of 91.7%, and negative predictive value of 56.5% for proximal LAD occlusions. When the ECG was performed more than 60 minutes after symptom onset (n = 37), there was no significant difference in ST-segment deviation between the 2 groups., Conclusion: The sum STE (V1-V6) and STD (II, III, aVF) on a 12-lead ECG can be used to predict proximal LAD occlusions if performed within the first hour of symptom onset. This should be considered a high-risk finding and may prompt prehospital direction of such patients to PCI-capable hospitals.

Objectives: We sought to quantify ranges of normal myocardial perfusion and flow reserve in young, asymptomatic volunteers after systematic historical and laboratory screening for unexpected factors affecting coronary flow., Background: Noninvasive cardiac positron emission tomography (PET) quantifies absolute flow and coronary flow reserve (CFR), thereby defining physiological severity of coronary artery disease for clinical studies or management. Defining "normal" coronary flow is a necessary prerequisite to its broad clinical application., Methods: Volunteers aged 20 to 40 years of age without cardiac disease or other conditions underwent rest-dipyridamole stress cardiac PET with absolute quantitative flow measurements using Rb-82 in paired studies at least 7 days apart for reproducibility. The presence of coronary calcium, detectable blood nicotine or caffeine, dyslipidemia, and an extended family history of early clinical atherosclerosis were objectively and systematically examined for grouping subjects as true normal or not normal., Results: We enrolled 125 volunteers, 107 (86%) underwent 2 PET scans. Fifty-six (45%) were classified as true normal, whereas 69 (55%) were classified as not normal. True normals had higher high-density lipoprotein and less PET scan heterogeneity. Hemodynamic responses to dipyridamole stress were similar. Rest flow was the same in both groups (0.72 ± 0.17 ml/min/g vs. 0.69 ± 0.14 ml/min/g, p = 0.164). However, stress flow (2.89 ± 0.50 ml/min/g vs. 2.63 ± 0.61 ml/min/g, p = 0.005) and CFR (4.17 ± 0.80 vs. 3.91 ± 0.86, p = 0.047) were higher in true normals. Paired studies were performed a median of 22 days (interquartile range: 15 to 39) apart. Reproducibility was improved in the true normal group., Conclusions: One-half of young, asymptomatic volunteers from the community harbor unexpected factors that mildly but systematically reduce stress flow, CFR, and reproducibility. This study establishes normal ranges and reproducibility for flow and CFR as the basis for clinical applications., (Copyright © 2011 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Introduction: Pelvic ischemia can manifest as vascular-mediated erectile dysfunction (ED) and lower urinary tract symptoms (LUTS), and is associated with cardiac ischemia., Aims: We aimed to develop a dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) technique to measure pelvic perfusion in benign tissue., Methods: Nine men with coronary artery disease (CAD) were compared with nine without. Images were acquired at 3T with T1-weighted DCE-MRI for perfusion. Two-compartment pharmacokinetic modeling was employed to fit signal enhancement from prostate, corpus cavernosal, and spongiosal tissues., Main Outcome Measures: Perfusion parameters and validated pelvic symptom scores were compared., Results: The mean International Index of Erectile Function (IIEF) total score was worse in CAD (41.3 +/- 19.7) vs. controls (59.4 +/- 14.9, P = 0.04). The IIEF erectile function domain score trended to worse in CAD (13.7 +/- 9.7) vs. controls (22.0 +/- 9.9, P = 0.09). The mean total International Prostate Symptom Score (IPSS) trended to worse in CAD patients (13.2) than controls (7.0) (P = 0.10). Magnetic resonance perfusion analysis demonstrated lower mean maximal percent enhancement to P < 0.0001 in the CAD group vs. controls for all the following comparisons: prostate in CAD (22.4 +/- 0.4) vs. controls (26.3 +/- 0.1); cavernosal tissue in CAD (9.3 +/- 0.2) vs. controls (16.6 +/- 0.8); and spongiosal tissue in CAD (20.6 +/- 1.2) vs. controls (24.0 +/- 0.6). Comparison of mean wash-in rates in the unit of 10(-3)/second was also highly significant (P < 0.0001 for all tissues): prostate in CAD (574.0 +/- 18.0) was lower than controls (1,035.0 +/- 29.0); slower wash-in rates were seen in CAD cavernosal (58.0 +/- 4.0 vs. 139.0 +/- 9.0 in controls) and spongiosal tissue (134.0 +/- 6.0 vs. 278.0 +/- 12.0 in controls)., Conclusion: These initial data demonstrate that pelvic perfusion can be measured in noncancerous tissues, and that perfusion correlates with validated measures of ED and LUTS.

Objectives: We sought to evaluate the impact of a strategy of reduced-dose fibrinolytic acceleration of ST-segment elevation myocardial infarction (STEMI) treatment followed by urgent percutaneous coronary intervention (FAST-PCI) on the mortality, reinfarction, and stroke rates in STEMI patients as compared with a primary percutaneous coronary intervention (PPCI) approach., Background: Time to reperfusion is a major determinant of mortality among STEMI patients. Rapid initiation of fibrinolytic therapy can shorten time to reperfusion, and mechanical therapy of the culprit lesion is known to be beneficial., Methods: Data from 2,869 STEMI patients treated in 5 high-volume percutaneous coronary intervention (PCI) centers were pooled for analysis. Mortality at 30 days was the primary end point. Death, reinfarction, and stroke were secondary end points, as were infarct-related artery TIMI (Thrombolysis In Myocardial Infarction) flow grade before PCI and shock on arrival to the catheterization laboratory., Results: Compared to PPCI, mortality at 30 days was significantly lower with FAST-PCI (3.8% vs. 6.4%, p = 0.002). The combined triple end point of death, reinfarction, or stroke was also less frequent (5.1% vs. 8.9%, p < 0.0001). The FAST-PCI patients had a lower incidence of Killip class IV (5.6% vs. 10.9%, p < 0.0001) and higher infarct-related artery TIMI flow grades (2.1 +/- 1.2 vs. 1.1 +/- 1.3, p < 0.0001) upon arrival in the catheterization laboratory. Stepwise logistic regression analysis demonstrated that FAST-PCI was an independent predictor of 30-day mortality (relative risk = 0.542, p = 0.0151)., Conclusions: The FAST-PCI strategy reduced the mortality and combined end point of death, reinfarction, and stroke among STEMI patients, without increasing the risk of stroke or bleeding, compared to PPCI. Fibrinolysis before hospital admission also increased the initial infarct-related artery patency and decreased the likelihood of shock at presentation.

Unlabelled: Cardiac PET/CT is optimized by cine CT with dedicated shift software for manual correction of attenuation-emission misregistration. Separate rest and stress CT scans incur greater radiation dose to patients than does standard helical PET/CT or "pure" PET using rotating rod attenuation sources. To reduce radiation dose, we tested quantitative accuracy of using a single poststress cine CT attenuation scan for reconstructing rest perfusion images to eliminate resting CT attenuation scans., Methods: A total of 250 consecutive patients underwent diagnostic rest-dipyridamole myocardial perfusion PET/CT with (82)Rb and a 16-slice PET/CT scanner using averaged cine CT attenuation data during breathing at rest and stress. After correcting for any attenuation-emission misregistration, we quantitatively compared resting perfusion images reconstructed using rest cine CT attenuation data with the same resting emission data reconstructed with poststress cine CT attenuation data. Automated software quantifying average regional quadrant activity, severity, size, and combined size and severity of perfusion defects was used for this comparison., Results: Resting perfusion images reconstructed using rest cine CT attenuation data were quantitatively comparable to resting images reconstructed with poststress cine CT attenuation data with no clinically significant differences. Twenty-five (10%) of 250 cases required shifting of stress cine CT attenuation data to achieve optimal attenuation-emission coregistration with resting perfusion data. Eliminating rest CT attenuation scans reduced CT radiation dose by 50% below rest-plus-stress cine CT protocols., Conclusion: Resting perfusion images reconstructed using poststress cine CT attenuation data are quantitatively comparable to resting images reconstructed with resting cine CT attenuation data. Eliminating the rest CT scan reduces CT radiation dose by 50%.

Background: In coronary artery disease (CAD), statins decrease morbidity and mortality but changes in myocardial perfusion abnormalities remain poorly defined., Methods: We completed a randomized, double blind, placebo controlled, multi-center trial of 145 patients, 43 to 86 years old, with CAD from seven community and academic centers for cardiac positron emission tomography (PET) randomized to 6 months of atorvastatin 80 mg daily (72 patients) or placebo (73 patients). PET scans were obtained at baseline, 6 weeks and 6 months using N-13 ammonia or Rb-82 at rest and after dipyridamole or adenosine stress, submitted to the core PET laboratory in Houston. Change in stress induced perfusion defects from baseline to follow-up PET scans was scored by two independent, double blinded readers and by automated quantitative software., Results: Total and LDL cholesterol decreased by 37% and 51%, respectively in atorvastatin but not placebo groups (P < .05). The primary endpoint, quantitative severity (lowest mean quadrant activity), showed no significant difference between treatment and placebo. The secondary endpoint, predefined blinded visual change scores, improved significantly after atorvastatin compared to placebo at six months (P = .02). Ad-hoc subgroup analysis showed interaction between quantitative defect size and treatment response with perfusion defects in the upper tertile of size by automated software improving more in atorvastatin than placebo groups (P = .016)., Conclusion: The primary endpoint, quantitative severity of myocardial perfusion abnormalities by PET, did not improve after 6 months of atorvastatin 80 mg daily compared to placebo. The secondary endpoint of predefined blinded visual change scores significantly improved, as did a subgroup in the upper tertile of defect size, compared to placebo.

Endothelin-1 is a powerful coronary vasoconstrictor that is overexpressed in coronary artery disease. Adenosine is a powerful coronary vasodilator used for myocardial perfusion imaging to identify flow-limiting coronary artery stenosis. Therefore, in an animal model we tested the hypothesis that intracoronary endothelin-1 may cause myocardial perfusion abnormalities by positron emission tomography (PET) at resting conditions that may persist or only partially improve after intravenous adenosine stress in the absence of myocardial scar and flow-limiting stenosis. Fourteen dogs underwent serial PET perfusion imaging with rubidium-82 before and after subselective intracoronary infusion of endothelin-1, followed by intravenous and then intracoronary adenosine. Small physiological doses of endothelin-1 infused into the mid-left circumflex coronary artery caused quantitatively significant resting perfusion abnormalities that normalized after intracoronary adenosine but not consistently after intravenous adenosine used for diagnostic imaging. After effects of adenosine abated, resting perfusion defects returned, lasting up to 5 h in some animals. Cumulative doses of endothelin-1 caused perfusion defects that did not normalize after intravenous adenosine. In an animal model without myocardial scar or flow-limiting stenosis, intracoronary endothelin-1 causes visually apparent, quantitatively significant, long-lasting myocardial perfusion defects at resting conditions that may persist or only partially improve after intravenous adenosine used for diagnostic imaging. These results may potentially explain resting perfusion abnormalities or heterogeneity by clinical PET that may persist or only partially improve after adenosine stress perfusion imaging in the absence of myocardial scar and flow-limiting stenosis.

Although mechanical circulatory support (MCS) can improve myocardial function in patients with advanced heart failure, its effects on relative myocardial perfusion are unclear. Using positron emission tomographic imaging techniques, the authors assessed relative myocardial perfusion in patients with ischemic or idiopathic cardiomyopathy who were receiving chronic MCS with a left ventricular assist device (pulsatile HeartMate [n = 2] [Thoratec Corporation, Pleasanton, CA] or nonpulsatile Jarvik 2000 [n = 4] [Jarvik Heart, Inc., New York, NY]). Relative myocardial perfusion was compared at lower and higher levels of MCS (50 vs. 100 - 110 ejections/min for the HeartMate and 8000 vs. 12,000 rpm for the Jarvik 2000). The size and severity of perfusion defects at rest and after dipyridamole stress were measured objectively and subjectively by computer algorithms and visual inspection, respectively. Relative myocardial perfusion increased > 5% from baseline in only one of six patients when MCS was increased. No change in relative myocardial perfusion of > 5% was seen in any of the other five patients, even after subsequent dipyridamole stress positron emission tomographic imaging. These pilot study findings suggest that the decreased metabolic requirements induced by ventricular unloading correspondingly decreased blood flow requirements to physiologically inactive myocardium.

Unlabelled: Changes in regional myocardial perfusion throughout the entire coronary vascular tree, as opposed to changes in the worst regional perfusion defect, have not been described during long-term regression or progression of coronary artery disease (CAD) or related to clinical outcomes., Methods: Four-hundred nine patients with CAD undergoing dipyridamole PET at baseline and after 2.6 +/- 1.4 y were followed over 5 more years for coronary events. PET images were objectively quantified by automated software for changes in severity of the (i) baseline worst quadrant, indicating the worst flow-limiting stenosis at baseline PET; (ii) follow-up worst quadrant, indicating the worst stenosis on follow-up PET; and (iii) maximal change quadrant, indicating the largest change of any same quadrant pair from baseline-to-follow-up images., Results: At follow-up PET, new regional perfusion defects were seen in 40% of patients. In 77% of patients, the greatest change was in a quadrant different from the worst baseline defect. The maximal change quadrant improved in 70% of patients on intense lifestyle and pharmacologic lipid treatment, in 48% on moderate treatment, and in 39% on poor treatment (P < 0.0001). Combined quadrant changes integrated throughout the heart independently predicted cardiovascular events at long-term follow-up. In contrast, changes of any single baseline-to-follow-up quadrant pair did not., Conclusion: By PET, 77% of patients with CAD had the greatest perfusion changes in areas different from the baseline worst perfusion defect and 40% had new perfusion defects. Changes in perfusion defects throughout the entire coronary vascular tree predicted coronary events, whereas changes in the worst flow-limiting stenosis at baseline or in any one segment of myocardium did not. To our knowledge, these data provide the first direct evidence on mechanisms for disproportionately greater reduction in cardiac events than changes in single stenosis severity with lipid treatment.

Background: Concern for major bleeding complications (MBC) may lead to withholding of anticoagulation and fibrinolytic therapy in preparation for primary percutaneous coronary intervention (PCI), potentially resulting in unacceptable delays in achieving reperfusion., Objectives: The primary objective of this study was to evaluate MBC associated with primary and rescue PCI and how timing to revascularization affects this variable., Methods: We evaluated 659 consecutive patients presenting within 24 hours of an acute ST elevation myocardial infarctions (MI). One hundred and eighty-three patients presented for rescue PCI and 476 for primary PCI. Eighty-seven rescue PCI patients were treated within 6 hours of their first dose of fibrinolytic. Demographics, procedural variables, outcomes, and major adverse cardiovascular events (MACE) were compared between the primary and rescue PCI groups and between early and late presenters in the rescue PCI group., Results: We observed that the incidence of MBC was 8% in patients undergoing rescue PCI and 6% in primary PCI (P=0.35). There were no significant differences in bleeding associated with GP IIb/IIIa receptor antagonist use, procedural success, or MACE. Similarly, in patients presenting for early or late rescue PCI there was no significant difference in MBC, procedural success, or MACE., Conclusions: We concluded that early or late rescue PCI and primary PCI have similar rates of MBC and overall in-hospital outcomes for patients presenting within 24 hours of acute MI. Delaying the timing of a rapid reperfusion strategy in an effort to decrease the incidence of MBC complications is generally not justified., ((J Interven Cardiol 2005;18:361-365).)

The objective of this study was to evaluate the effectiveness of two different closure devices in patients undergoing rescue percutaneous coronary intervention (PCI) using IIb/IIIa inhibitors and to compare it with patients undergoing elective PCI. One hundred sixty-two patients undergoing rescue PCI treated with IIb/IIIa inhibitors underwent vascular access site closure (6 Fr Perclose, n = 92, or 6 Fr Angioseal, n = 70). Vascular complications were compared with a sex- and age-matched group (n = 100) of patients undergoing manual compression after sheath removal and a similar group of patients undergoing elective PCI (n = 196). The incidence of access site complications was not significantly different between the three groups undergoing rescue PCI and was not higher than in patient receiving GP IIb/IIIa inhibitors without fibrinolysis (RR = 0.95; 95% CI = 0.88-1.01). In patients undergoing rescue PCI and receiving IIb/IIIa inhibitors, closure devices allow early sheath removal and are associated with similar outcomes compared with manual compression and elective PCI regardless of the type of closure device used.

Percutaneous revascularization has become an effective treatment for patients suffering from chronic critical limb ischemia (CLI) due to chronic atherosclerotic obstructions, including total occlusions. Unlike other vascular beds, total chronic occlusions of the femoropopliteal arteries are frequently found in patients with severe claudication or CLI. As a consequence, patients with long chronic total occlusions of the femoropopliteal arteries are generally not considered optimal candidates for percutaneous revascularization and are frequently referred for surgical revascularization. In the present study, we sought to evaluate the feasibility, safety, and outcome of a modified wireless laser ablation technique to recanalize total occlusions in patients with CLI who had failed conventional percutaneous techniques for limb salvage. Procedural success, complications, actuarial freedom of limb loss, and surgical revascularization were evaluated in 25 patients after a mean follow-up of 13 +/- 8 months. Procedural success was achieved in 21 patients (84%). Actuarial freedom from surgical revascularization or limb loss was 72%. There was one vascular perforation. No deaths or distal embolization occurred. Three patients (12%) required limb amputation during follow-up, whereas four patients (16%) had surgical revascularization in the presence of feasible vascular targets. Limb salvage was achieved in 88% of patients when laser recanalization was combined with surgical revascularization. These results suggest that the use of laser ablation is safe and facilitates angioplasty and stenting in patients with CLI that failed conventional endovascular revascularization. This technique might prevent limb loss in patients with CLI due to femoropopliteal total occlusions, particularly in patients with unsuitable anatomy for surgical revascularization.

Catheter-induced left main coronary artery dissection is quite rare. We describe two cases of iatrogenic left main coronary artery dissection. In the first case, the aortic root was involved in the dissection process, and stenting of the entry point did not halt the progression of dissection. In the second case, the dissection did not involve the aortic root.

Unlabelled: Misregistration between attenuation and emission images causes artifactual abnormalities on cardiac PET images that result in false-positive defects. This study determines the frequency and mechanisms of misregistration artifacts, identifies their predictors, and validates a method for their routine clinical identification, prevention, or correction., Methods: We performed 1177 consecutive diagnostic myocardial perfusion PET studies using 1 of 3 protocols: (a). 3 initial consecutive measured attenuation correction (MAC) scans, followed by resting and dipyridamole emission scans; (b). an initial MAC scan (early MAC), followed by emission scans; and (c). a MAC attenuation scan obtained after emission scans (late MAC). Emission images were manually shifted to obtain coregistration with attenuation and reconstructed again using shifted emission data that eliminated artifactual defects. Measurements on PET images included heart size, heart and diaphragm displacement after dipyridamole, objective quantitative misregistration of attenuation and emission images, and size or severity of image defects before and after shifting emission images., Results: Of 1,177 rest-dipyridamole PET perfusion studies, 252 (21.4%) had artifactual defects due to attenuation-emission misregistration. By shifting emission images, quantitative severity and size of misregistration and artifactual defects significantly decreased (P < 0.001) with visual normalization. Artifactual defects were predicted by horizontal plane misregistration (odds ratio [OR] = 1.545, confidence intervals [CI] = 1.113-2.145, P = 0.009), body mass index (OR = 2.659, CI = 1.032-6.855, P = 0.043), and whole heart area in the horizontal plane at rest (OR = 1.096, CI = 1.018-1.179, P = 0.015). Quantitative misregistration was predicted by diaphragm displacement between rest and dipyridamole (P = 0.001, CI = 0.158-0.630), body mass index (P = 0.005, CI = 0.202-1.124), and whole heart area in the horizontal plane at rest (P = 0.004, CI = -0.144 to -0.028). Diaphragm displacement was significantly larger for obese compared with lean patients (P = 0.027) during the initial 10 min of the imaging protocol., Conclusion: Misregistration of attenuation and emission images is common in cardiac PET imaging and causes artifactual defects predicted by diaphragmatic displacement, body mass index, and heart size. Multiattenuation imaging sequences and manual, visually optimized coregistration of attenuation and emission images substantially eliminate artifacts for reliably identifying mild perfusion defects of early nonobstructive coronary atherosclerosis as the basis for intense lifestyle and pharmacologic treatment.

Elderly patients are increasingly referred to percutaneous coronary interventions (PCIs). Recent reports suggest complications rates are declining in the elderly. We sought to determine whether procedural and in-hospital outcomes are different in patients aged > or = 75 years undergoing nonemergent PCI as compared to patients age < 75 years. The outcome of 266 consecutive patients age > or = 75 years undergoing nonemergent PCI was compared to that of 1,681 consecutive patients age < 75 years. Compared with younger patients, greater proportions of elderly patients were women and had a history of hypertension, peripheral vascular disease, and cerebral vascular events. Elderly patients had more extensive coronary involvement. Procedural success was similar in both groups (94%). The in-hospital cardiac death rate was significantly higher in the elderly patients (2.3% vs. 0.7%; P = 0.03). Aged patients also had a significantly higher incidence of vascular and bleeding complications. Blood transfusion was required more often in the elderly group (4.5% vs. 2.6%; P = 0.07). The hospitalization length was significantly higher in the elderly group (4.1 +/- 6.0 vs. 2.5 +/- 4.3 day; P = 0.0004). By multivariate logistic regression (adjusted for baseline clinical and angiographic variables), age > or = 75 years was found to be an independent predictor of in-hospital cardiac death (odds ratio = 3.9; 95% CI = 1.3-11.5; P = 0.015). Although PCI is technically successful in patients aged > or = 75 years; it is associated with more acute cardiac and vascular complications and higher in-hospital cardiac mortality., (Copyright 2003 Wiley-Liss, Inc.)

The use of radiographic contrast during cardiac catheterization can cause acute renal failure with an increase in morbidity and mortality. Prophylactic acetylcysteine plus intravenous hydration have been shown to prevent contrast-induced nephropathy (CIN) in patients with chronic renal failure undergoing computed tomography scan, who receive low doses of intravenous contrast. Whether the use of prophylactic acetylcysteine can decrease the incidence of CIN when larger doses of contrast are used remains to be determined. We sought to evaluate whether the prophylactic administration of acetylcysteine plus intravenous hydration is superior to intravenous hydration alone in prevention of CIN in patients with chronic renal failure undergoing cardiac catheterization and receiving moderate to high doses of intravenous contrast (> 1 cc/kg). Seventy-three consecutive patients with renal insufficiency who received intravenous hydration and 600 mg of acetylcysteine twice a day 24 hr before and the day of the cardiac catheterization were compared with 106 consecutive patients who received hydration alone. Baseline and 48-hr serum creatinine concentrations were compared between the two groups before and after cardiac catheterization. Multivariate and univariate analysis were performed to assess the effects of acetylcysteine and other clinical variables in the change of serum creatinine after the procedure. Both groups had comparable clinical characteristics and received similar volumes of intravenous hydration. The volume of contrast used was similar for the two groups (2.2 +/- 1.7 vs. 2.3 +/- 1.5 cc/kg; P = 0.67). A mean change in serum creatinine of 0.17 +/- 0.54 mg/dl for the acetylcysteine group vs. 0.19 +/- 0.40 mg/dl for the control group (P = 0.77) was observed at 48 hr. The incidence CIN was 13% in the acetylcysteine vs. 12% in the control group (P = 0.84). Acetylcysteine, whether analyzed with multivariate or univariate analysis, failed to demonstrate a significant effect in the change of serum creatinine after cardiac catheterization. In patients with chronic renal insufficiency, acetylcysteine in a dose of 600 mg twice a day before and after cardiac catheterization, along with intravenous fluids, is as effective as fluids alone in the prevention of CIN when moderate to high doses of contrast are used., (Copyright 2003 Wiley-Liss, Inc.)

The most consistent procedural predictor of vascular access site complications thus far has been the intensity and duration of anticoagulant therapy during and after percutaneous coronary interventions (PCI). Several devices have been developed to aid in the closure of the femoral arteriotomy. This report describes the clinical outcome of unsuccessful deployment of femoral closure devices in a cohort of 285 consecutive patients who underwent PCI and were treated with platelet glycoprotein (GP) IIb/IIIa inhibitors. Manual femoral artery compression was used in 123 patients, Perclose in 123 patients, and AngioSeal in 39 patients. Successful homeostasis was achieved in 98.4% of patients who received manual compression, in 91.9% of the Perclose-sealed arteriotomy, and in 84.6% of patients who received the AngioSeal closure device (P = 0.004). The incidence of vascular complications after successful deployment was 9%. Patients not achieving hemostasis with closure device or 1 degrees manual compression developed complications in the majority of cases (> 80%; P < 0.05). By multivariate analysis (with adjustment for baseline differences), the use of AngioSeal closure device was found to be an independent risk factors leading to primary deployment failure and all access site complications (OR 2.97; 95% CI 1.5-6.0; P = 0.006). In summary, failed hemostasis by artery closure devices in patients undergoing PCI who are treated with GP IIb/IIIa inhibitors is associated with significant vascular complications. AngioSeal may be associated with a higher failure rate, while manual compression and Perclose seem to be more effective with a lower complication rate., (Copyright 2003 Wiley-Liss, Inc.)

Intracoronary beta (beta) radiation decreases the incidence of target lesion revascularization after percutaneous intervention (PCI) for in-stent restenosis (ISR). Cutting balloon (CB) angioplasty may also be superior to other percutaneous techniques for the treatment of ISR. We sought to study the outcomes of patients with ISR who underwent both CB angioplasty and intracoronay beta radiation and compare them to patients with ISR who underwent other PCI techniques without concomitant radiation. We also sought to evaluate the safety and efficacy of pullback intracoronary beta radiation for the treatment of long ISR lesions. Between January 2001 and November 2001, 102 patients (mean age = 55 +/- 13 years) with ISR underwent both CB angioplasty and intracoronay beta radiation. beta radiation was delivered using the Beta Cath (Novoste) 30 mm system, and pullback radiation was performed in 41 patients. A comparison group included a total of 393 patients with ISR who underwent other PCI techniques without concomitant intracoronary radiation therapy. Follow-up was obtained in 99 patients (97%) in the CB angioplasty with intracoronary radiation group and 377 patients (96%) in the comparison group. At follow-up, both target vessel revascularization (TVR) and major adverse cardiovascular events (MACE) occurred significantly less in the CB angioplasty with intracoronary radiation group than in the comparison group (7% vs. 18% for TVR, and 14% vs. 24% for MACE; P < 0.05 for both). In the pullback radiation group, TVR was performed in five patients (12%), and MACE occurred in eight patients (20%). A combination of CB angioplasty and intracoronay beta radiation for ISR seems to yield low rates of subsequent target vessel revascularization and adverse cardiac events. In addition, pullback beta radiation using the Beta Cath (Novoste) 30 mm system is safe and can be used to treat long ISR lesions effectively. Further randomized trials are needed to confirm these findings., (Copyright 2002 Wiley-Liss, Inc.)

Abciximab therapy improves clinical outcomes after percutaneous interventions for de novo coronary artery disease. We sought to determine whether clinical outcomes after percutaneous intervention for in-stent restenosis are affected by abciximab administration. Between January 1996 and July 1999, 322 consecutive patients underwent percutaneous intervention for in-stent restenosis; 157 patients received abciximab and 165 patients were treated without abciximab based on operator discretion. Baseline clinical and angiographic variables and type of percutaneous intervention were recorded. Follow-up information was obtained and clinical endpoints were recorded. A multivariate analysis was performed to determine the independent variables associated with adverse clinical outcomes. Baseline clinical and angiographic variables were similar in both groups. Patients who received abciximab were more likely to be treated with rotational atherectomy and less likely to have only balloon angioplasty or repeat stenting. Mean follow-up duration was 19 +/- 12 months. There were no significant differences in the incidence of angina/myocardial infarction (29% vs. 30%; P = 0.9), target vessel revascularization (18% vs. 21%; P = 0.5), death (8% vs. 7%; P = 0.4), or major adverse cardiovascular events (38% vs. 39%; P = 0.9) in both groups. Abciximab administration was not an independent variable associated with adverse outcomes. In this observational study, clinical outcomes after percutaneous intervention for in-stent restenosis did not seem to be affected by abciximab administration. Randomized trials are needed to identify the role of platelet glycoprotein IIb/IIIa inhibitors in the management of in-stent restenosis., (Copyright 2002 Wiley-Liss, Inc.)

Slow or no-reflow phenomenon (SNR) complicates 10%-15% of cases of percutaneous intervention (PCI) in aortocoronary saphenous vein grafts (SVG). At present, there are no uniform, effective strategies to predict or prevent this common and potentially serious complication. The purpose of our study was to characterize variables correlated with the risk of SNR in SVG PCI in the era of stenting and glycoprotein IIb/IIIa receptor inhibitors. We identified 2,898 consecutive patients who had PCI, of whom 163 underwent PCI of at least one SVG. The clinical and angiographic characteristics of patients who developed SNR (SNR group) were compared with those who did not (no-SNR group). A total of 23 patients experienced SNR and 140 did not. Using a stepwise multivariate logistic regression analysis, four independent predictors for SNR were detected: probable thrombus (OR 6.9; 95% CI, 2.1-23.9; P = 0.001), acute coronary syndromes (OR 6.4; 95% CI, 2.0-25.3; P = 0.003), degenerated vein graft (OR 5.2; 95% CI, 1.7-16.6; P = 0.003), and ulcer (OR 3.4; 95% CI, 0.99-11.6; P = 0.04). The risk of developing SNR could be estimated according to the number of predictors found: low-grade risk (1%-10%) if < or = one variable was present, moderate risk (20%-40%) if two variables were present, and high risk (60%-90%) if three or more variables were present. We identified and quantified current risk factors for SNR and concluded that the risk of developing SNR during PCI in SVG can be predicted by simple clinical and angiographic variables obtained before PCI. This information may be useful when the risk of PCI has to be balanced against alternative strategies such as medical therapy or redo-bypass surgery or in the selection of those patients that will most benefit from the use of protection devices during PCI., (Copyright 2001 Wiley-Liss, Inc.)

Background: The histological appearance of stenosis in de novo saphenous venous grafts (DNSVG) consists of diffuse atherosclerosis that contains blood elements, necrotic debris and limited fibrocollagenous tissue. The friable nature of these lesions complicates percutaneous intervention (PCI) procedures. On the other hand, in-stent restenosis (ISR) of SVG is due primarily to atherosclerotic plaque or fibromuscular hyperplasia, with thrombus formation playing a secondary role. The purpose of this study is to compare the results of PCI in these two types of SVG lesions., Methods: We reviewed our institutional interventional database from March 1996 through February 2000 and identified all consecutive patients who underwent PCI of at least one SVG. One hundred and ten patients were identified: 89 undergoing DNSVG intervention and 21 patients with ISR lesions., Results: Acute coronary syndromes, degenerated and thrombus-containing lesions were more common in the DNSVG group. "Slow-, no-reflow" complicated 20% of the DNSVG lesions compared to none of the ISR lesions (p = 0.02). Post-procedural myocardial infarction was higher in the DNSVG group (13.5% versus 0%; p = 0.1) and correlated significantly with the occurrence of "slow-, no-reflow" (r = 0.43; p = 0.0001). Utilizing statistical modeling to adjust for baseline differences between the groups, ISR lesions were associated with a low risk of procedural complications (r = 0.22; p = 0.03)., Conclusion: This study demonstrates that in this relatively high-risk population, PCI is safer in ISR lesions than in de novo SVG lesions.