Combination therapy with clopidogrel and aspirin after coronary stenting.

Combination antiplatelet therapy using aspirin and ticlopidine has been the standard of care for prevention of subacute thrombosis following coronary stent implantation. However, the use of ticlopidine is associated with a significant risk of adverse hematologic side effects. Clopidogrel is an inhibitor of ADP-induced platelet aggregation that has a better safety profile than ticlopidine. We examined the 30-day clinical outcome following coronary stent implantation in 253 consecutive patients treated with clopidogrel and aspirin. Follow-up was achieved in 99% of patients and four adverse events were documented. Two patients had angiographically confirmed subacute stent thrombosis (0.8%), and both of these patients underwent successful repeat angioplasty at the stent site. There were two patient deaths during follow-up (0. 8%). One was sudden within 1 week of stent placement and the other occurred in a patient with multisystem organ failure after an extensive myocardial infarction that antedated the stent procedure, with no clinical evidence for stent thrombosis. The combined frequency of subacute stent thrombosis and death was 1.6%. This is comparable to prior studies using the combination of ticlopidine and aspirin following stenting. Therefore, clopidogrel in combination with aspirin appears to be a safe and effective therapy in the prevention of subacute thrombosis following coronary stent implantation.

Predictors of clinical outcome following percutaneous intervention for in-stent restenosis.

Percutaneous intervention for the first episode of in-stent restenosis was performed in 177 patients 5.4 +/- 0.3 months after native coronary stent implantation. Medical records were reviewed and patients contacted 13.3 +/- 1.2 months after in-stent intervention to ascertain the subsequent clinical course. The effects of demographic, procedural, and angiographic variables on clinical outcomes were determined. At 2 years, Kaplan-Meier estimated survival was 93 +/- 3% and freedom from death, myocardial infarction, and a third target artery revascularization (TAR) was 67 +/- 4%. The actuarial frequency of a third TAR was 26 +/- 4% at 1 year. Stratification of outcomes according to timing of in-stent intervention revealed an approximate twofold higher frequency of adverse events among patients with early (

Randomized trial of contrast media utilization in high-risk PTCA: the COURT trial.

BACKGROUND: Previous in vitro and in vivo studies have suggested an association between thrombus-related events and type of contrast media. Low osmolar contrast agents appear to improve the safety of diagnostic and coronary artery interventional procedures. However, no data are available on PTCA outcomes with an isosmolar contrast agent. METHODS AND RESULTS: A multicenter prospective randomized double-blind trial was performed in 856 high-risk patients undergoing coronary artery intervention. The objective was to compare the isosmolar nonionic dimer iodixanol (n=405) with the low osmolar ionic agent ioxaglate (n=410). A composite variable of in-hospital major adverse clinical events (MACE) was the primary end point. A secondary objective was to evaluate major angiographic and procedural events during and after PTCA. The composite in-hospital primary end point was less frequent in those receiving iodixanol compared with those receiving ioxaglate (5.4% versus 9.5%, respectively; P=0.027). Core laboratory defined angiographic success was more frequent in patients receiving iodixanol (92.2% versus 85. 9% for ioxaglate, P=0.004). There was a trend toward lower total clinical events at 30 days in patients randomized to iodixanol (9.1% versus 13.2% for ioxaglate, P=0.07). Multivariate predictors of in-hospital MACE were use of ioxaglate (P=0.01) and treatment of a de novo lesion (P=0.03). CONCLUSIONS: In this contemporary prospective multicenter trial of PTCA in the setting of acute coronary syndromes, there was a low incidence of in-hospital clinical events for both treatment groups. The cohort receiving the nonionic dimer iodixanol experienced a 45% reduction in in-hospital MACE when compared with the cohort receiving ioxaglate.

American College of Cardiology/European Society of Cardiology International Study of Angiographic Data Compression Phase I: The effect of lossy data compression on recognition of diagnostic features in digital coronary angiography.

OBJECTIVES: This study intended to determine the effect of varying degrees of lossy Joint Photographic Experts Group (JPEG) compression on detection of coronary angiographic features. BACKGROUND: Compression of digital coronary angiograms facilitates playback of images and decreases cost. There are little data on the effect of compression on the accuracy of coronary angiography. METHODS: At six centers, 71 angiographers each reviewed a set of 100 angiographic sequences. The 100 sequences were divided into four, 25-sequence subsets. Each subset of 25 was displayed either as original images or at one of three compression ratios (CRs) (6:1, 10:1 or 16:1). The effect of lossy compression on the sensitivity and specificity for detection of diagnostic features was determined. The effect of compression on subjective measures of image quality graded by the angiographers was also examined. RESULTS: Lossy compression at a ratio of 16:1 decreased the sensitivity for the detection of diagnostic features (76% vs. 80% p = 0.004). The largest effect was in the detection of calcification (52% vs. 63% at 16:1 compression vs. original images, p < 0.001). Subjective indicators of image quality indicated a reduction in confidence in interpretation at CRs of 10:1 and 16:1. CONCLUSIONS: With increased ratios of lossy compression, a degradation of digital coronary angiograms occurs that results in decreased diagnostic accuracy. The sensitivity for detection of common diagnostic features was decreased, and subjective assessment of image quality was impaired. Caution is warranted in the interpretation of coronary angiograms that have been subjected to lossy JPEG compression beyond a ratio of 6:1.

American College of Cardiology/ European Society of Cardiology international study of angiographic data compression phase I. The effects of lossy data compression on recognition of diagnostic features in digital coronary angiography.

OBJECTIVES: This study intended to determine the effect of varying degrees of lossy Joint Photographic Experts Group (JPEG) compression on detection of coronary angiographic features. Background Compression of digital coronary angiograms facilitates playback of images and decreases cost. There are little data on the effect of compression on the accuracy of coronary angiography. METHODS: At six centers, 71 angiographers each reviewed a set of 100 angiographic sequences. The 100 sequences were divided into four, 25-sequence subsets. Each subset of 25 was displayed either as original images or at one of three compression ratios (CRs) (6:1, 10:1 or 16:1). The effect of lossy compression on the sensitivity and specificity for detection of diagnostic features was determined. The effect of compression on subjective measures of image quality graded by the angiographers was also examined. RESULTS: Lossy compression at a ratio of 16:1 decreased the sensitivity for the detection of diagnostic features (76% vs. 80%P=0.004). The largest effect was in the detection of calcification (52% vs. 63% at 16:1 compression vs. original images, P<0.001). Subjective indicators of image quality indicated a reduction in confidence in interpretation at CRs of 10:1 and 16:1. CONCLUSIONS: With increased ratios of lossy compression, a degradation of digital coronary angiograms occurs that results in decreased diagnostic accuracy. The sensitivity for detection of common diagnostic features was decreased, and subjective assessment of image quality was impaired. Caution is warranted in the interpretation of coronary angiograms that have been subjected to lossy JPEG compression beyond a ratio of 6:1.

Complications of cardiac angiography using low- or high-osmolality contrast agents in patients with left main coronary stenosis.

Recently published guidelines suggest that, in view of cost concerns, low-osmolal contrast should be selectively used in patients at increased risk of experiencing a contrast-related complication during cardiac angiography. The suggested criteria include the presence of left main coronary disease. However, the presence of left main disease is not usually known prior to angiography. Contrast-related complications of cardiac angiography were therefore analyzed in a group of 111 clinically stable patients found to have left main coronary stenosis, to determine if use of low-osmolality contrast had any beneficial effect when compared to standard contrast. Data were gathered prospectively as part of a randomized controlled trial, and the subgroup of patients with left main disease was analyzed retrospectively. Complications were divided into minor, intermediate, and major categories. In the 58 patients who received high-osmolar contrast, there were 4 contrast-related minor reactions, 8 intermediate events requiring treatment, and 1 major adverse event. Among the 53 patients who received low-osmolar contrast, there were no minor reactions, 7 intermediate events requiring treatment, and no major adverse events. The only difference of borderline significance was in the incidence of minor reactions requiring no treatment (P = 0.05). Although small and therefore not definitive, this study suggests that 1) universal use of low-osmolar contrast agents would not be expected to eliminate the risk of contrast-related reactions to cardiac angiography; 2) the well-documented clinical differences between high- and low-osmolar contrast primarily involve mild reactions; and 3) standard high-osmolar contrast is reasonably safe in clinically stable patients with left main coronary stenosis. The results therefore are consistent with the notion that selective use of low-osmolar contrast only in unstable patients is safe and appropriate.

Acute and long-term outcome after Palmaz-Schatz stenting: analysis from the New Approaches to Coronary Intervention (NACI) registry.

The randomized Stent Restenosis Study (STRESS) and Belgium Netherlands Stent (Benestent) trials established that elective use of Palmaz-Schatz stents (PSSs) in native coronary arteries with de novo lesions is associated with increased procedural success and reduced restenosis. However there are other clinical indications for which stents are commonly used (unplanned use, vein grafts, restenosis lesions) that are not addressed in these studies. From 1990-1992, 688 lesions in 628 patients were treated with PSSs in the New Approaches to Coronary Intervention (NACI) registry. Angiographic core laboratory readings were available for 543 patients (595 lesions, of which 106 were stented for unplanned indications, 239 were in saphenous vein bypass grafts, and 296 were previously treated). The cohort of patients in whom stents were placed for unplanned indications had more women, current smokers, and had a higher incidence of recent myocardial infarction (MI). Patients who underwent stenting of saphenous vein grafts were older, had a higher incidence of diabetes mellitus, unstable angina, prior MI, and congestive heart failure. Lesion success was similar in all cohorts (98%), but procedural success was significantly higher for planned stenting (96% vs 87%; p < 0.01). Predictors of adverse events in-hospital were presence of a significant left main stenosis and stenting for unplanned indication. The incidence of target lesion revascularization by 30 days was significantly higher for patients undergoing unplanned stenting due to a higher risk for stent thrombosis. Recent MI, stenting in native lesion, and small postprocedural minimum lumen diameter independently predicted target lesion revascularization at 30 days. Independent predictors of death, Q-wave myocardial infarction, or target lesion revascularization at 1 year included severe concomitant disease, high risk for surgery, left main disease, stenting in the left main coronary artery, and low postprocedure minimum lumen diameter.

Comparison of outcome after stenting for de novo versus restenotic narrowings in native coronary arteries.

Intracoronary stenting of de novo narrowings results in a lower restenosis rate when compared with percutaneous transluminal coronary angioplasty. We sought to determine whether intracoronary stenting for restenotic narrowings is associated with a worse outcome when compared with stenting for de novo narrowings. A total of 114 consecutive patients with 124 narrowings were retrospectively identified. Stents were deployed in 46 de novo (37%) and in 78 restenotic (63%) narrowings. The 2 groups were similar with respect to variables known to affect restenosis. Follow-up angiograms were available in 88% of patients at a mean of 6.3 +/- 3.3 months after stent implantation. At follow-up angiography, a significantly higher restenosis rate in the restenotic group was observed (p = 0.05). Restenosis risk could not be predicted from variables known at the time of stent implantation. However, the presence of angina at the time of follow-up was significantly associated with restenosis (p = 0.01). Kaplan-Meier survival curves for freedom from repeat target-site revascularization demonstrated a significant difference in the need for target-site revascularization between the de novo and restenotic groups over the first-year post-stent implantation (p = 0.01; relative risk = 1.94). Multivariate analysis identified restenosis as the indication for stenting (p <0.01), postprocedure percent stenosis (p = 0.01), and narrowing length (p = 0.01) as independent predictors for repeat target-site revascularization. When compared with de novo narrowings, restenotic narrowings have a worse outcome after stenting. A prospective, randomized trial comparing outcome after percutaneous transluminal coronary angioplasty and stents for restenotic narrowings would be useful.

Three-year clinical follow-up after Palmaz-Schatz stenting.

OBJECTIVES: Our goals were to examine late clinical outcome in a cohort of patients who electively received Palmaz-Schatz intracoronary stents, to identify specific predictors of outcome and to determine the time course of the development of ischemic cardiac events after stenting. BACKGROUND: Short-term results of Palmaz-Schatz intracoronary stenting have been promising, with a reduction in both angiographic restenosis and clinical cardiac events up to 1 year after stenting. METHODS: We analyzed the clinical outcomes in 65 consecutive patients who underwent stenting at least 3 years before analysis. Demographic, clinical and procedural predictors of survival and event-free survival, defined as freedom from myocardial infarction, stent-site percutaneous transluminal coronary angioplasty, coronary artery bypass graft surgery or death, were analyzed at a mean follow-up of 39 +/- 17 months. RESULTS: Absolute survival and event-free survival at 3 years were 88% and 56%, respectively. Three-year freedom from stent-site revascularization was 66%. Predictors of decreased long-term survival (p < 0.05) included diabetes and a high angina score (Canadian Cardiovascular Society class III/IV) at 6 and 12 months after stenting. Predictors of decreased event-free survival (p < 0.05) included a high angina score at 3, 6 and 12 months after stenting, smaller stent deployment balloon size and greater number of stents implanted. Freedom from adverse events by 6 months after stenting also correlated with long-term event-free survival. Eighty-five percent of stent-site revascularizations occurred within 1 year. During late follow-up (>24 months), no patients had stent-site stenoses requiring revascularization, whereas 11% of patients required revascularization in nonstented coronary segments. CONCLUSIONS: Clinical predictors of worse long-term outcome included diabetes mellitus, higher angina score at follow-up, smaller stent deployment balloon size and greater number of stents at implantation. During follow-up, the majority of adverse events and stent-site revascularizations occurred early after stenting, and disease progression in nonstented vessels accounted for the majority of late revascularization events.

A randomized clinical trial of the effect of bed position after PTCA.

BACKGROUND: After percutaneous transluminal coronary angioplasty, prolonged supine bedrest with the bed flat frequently causes back pain. This study was conducted to examine whether percutaneous transluminal coronary angioplasty patients could adjust their bed position to make themselves comfortable without increasing the frequency or severity of bleeding complications. OBJECTIVES: To determine whether the risk of bleeding increased in patients who were allowed to use their bed controls to make themselves comfortable, and if the difference in comfort was significant between patients who controlled and elevated their bed position and patients who remained flat in bed. METHOD: A randomized clinical trial was conducted; 54 patients undergoing percutaneous transluminal coronary angioplasty were randomly assigned to either the control group, in which patients remained flat in bed, or the experimental group, in which they controlled their bed position. Outcome measures included amount of bleeding at the catheter sites and patient comfort. RESULTS: No difference in the amount of bleeding at catheter insertion sites was found between the two groups. Few subjects reported pain at any time. Back pain at dinner and bedtime was higher in the control group, but only the bedtime difference was statistically significant. CONCLUSION: We conclude that patients may be allowed to adjust their bed position to 30 degrees for comfort without incurring increased risk of catheter entry site bleeding and that requiring patients to remain flat in bed has no scientific basis.