OBJECTIVES:This registry collected the 30-day and 9-month clinical outcomes of patients whose coronary stent implantation was suboptimal, and compared them with the cohort of patients with "optimal" stenting in the randomized portion of the STent Anti-thrombotic Regimen Study (STARS) trial.BACKGROUND:Although "optimal" stenting combined with an aspirin and ticlopidine regimen carries a low (0.5%) incidence of subacute stent thrombosis, only limited data are available for patients in whom stents are deployed suboptimally.METHODS:In the STARS, 312 (15.9%) of 1,965 patients enrolled were excluded from participation in the randomized trial based on a perceived "suboptimal" result of coronary stenting. Of these, 265 patients met prespecified criteria for suboptimal stenting, and were followed in a parallel registry, which was compared with the randomized STARS optimal stenting cohort. The primary end point was a 30-day composite of death, emergent target lesion revascularization, angiographic thrombosis of the target vessel without revascularization and nonfatal myocardial infarction (MI) unrelated to direct procedural complications.RESULTS:Registry patients had a similar frequency of the primary end point compared with the overall randomized cohort (3.0% vs. 2.2%), with this end point correlating to use of multiple stents, smaller final lumen diameter and absence of ticlopidine from the poststent regimen. Overall 30-day mortality (1.1% vs. 0.06%, p = 0.009) and periprocedural non-Q wave MI (8.7% vs. 4.2%, p = 0.003) were more frequent in registry patients, and appeared to be related to acute procedural complications. Clinical restenosis was significantly higher for registry patients (26.8% vs. 16.0%, p = 0.001), relating to greater prevalence of independent predictors such as smaller final lumen diameter and multiple stent use.CONCLUSIONS:In the STARS registry, the inability to perform optimal stenting correlated with smaller final lumen diameter and longer stent length. With ticlopidine-containing regimens, the acute clinical results of "suboptimal" stent deployment are clinically acceptable, although they are not quite as good as those of optimal stenting using similar drug therapy.
BACKGROUND Antithrombotic drugs are used after coronary-artery stenting to prevent stent thrombosis. We compared the efficacy and safety of three antithrombotic-drug regimens - aspirin alone, aspirin and warfarin, and aspirin and ticlopidine - after coronary stenting. METHODS Of 1965 patients who underwent coronary stenting at 50 centers, 1653 (84.1 percent) met angiographic criteria for successful placement of the stent and were randomly assigned to one of three regimens: aspirin alone (557 patients), aspirin and warfarin (550 patients), or aspirin and ticlopidine (546 patients). All clinical events reflecting stent thrombosis were included in the prespecified primary end point: death, revascularization of the target lesion, angiographically evident thrombosis, or myocardial infarction within 30 days. RESULTS The primary end point was observed in 38 patients: 20 (3.6 percent) assigned to receive aspirin alone, 15 (2.7 percent) assigned to receive aspirin and warfarin, and 3 (0.5 percent) assigned to receive aspirin and ticlopidine (P=0.001 for the comparison of all three groups). Hemorrhagic complications occurred in 10 patients (1.8 percent) who received aspirin alone, 34 (6.2 percent) who received aspirin and warfarin, and 30 (5.5 percent) who received aspirin and ticlopidine (P<0.001 for the comparison of all three groups); the incidence of vascular surgical complications was 0.4 percent (2 patients), 2.0 percent (11 patients), and 2.0 percent (11 patients), respectively (P=0.01). There were no significant differences in the incidence of neutropenia or thrombocytopenia (overall incidence, 0.3 percent) among the three treatment groups. CONCLUSIONS As compared with aspirin alone and a combination of aspirin and warfarin, treatment with aspirin and ticlopidine resulted in a lower rate of stent thrombosis, although there were more hemorrhagic complications than with aspirin alone. After coronary stenting, aspirin and ticlopidine should be considered for the prevention of the serious complication of stent thrombosis.
Aim: To determine the efficacy of new coronary interventions in women and the elderly.Patients and methods: We studied 504 patients who underwent a total of 567 procedures, comprising 275 directional coronary atherectomy and 292 Palmaz-Schatz stents over a 2 1/2 year period; 18% were women and 23% were aged greater than or equal to 70 years (elderly).Results: High rates of success were obtained with these procedures in women and the elderly, although the rates were lower in women than in men (89 versus 96%, P=0.005), and similarly lower in the elderly than in younger patients (91 versus 96%, P=0.06). In addition to the lower success rates, there was a higher incidence of procedure-related non-Q myocardial infarction and vascular complications in both the women and the elderly independently. The degree of angiographic restenosis (greater than or equal to 50% diameter stenosis), however, was similar in women (36 versus 28% in men, P=0.22) and in the elderly (28 versus 29% in patients ages <70 years, P=0.8). There were no sex-related differences in survival, late myocardial infarction, or repeat revascularization. In the elderly, although the incidence of repeat revascularization was not increased, there was a decrease in late survival (P<0.001) and an increase in the incidence of late myocardial infarction (P=0.02), probably reflecting the presence of other co-morbid variables.Conclusion: Both directional coronary atherectomy and coronary stenting can be performed safely and effectively in women and the elderly with good long-term clinical results, despite a somewhat lower rate of success and similarly higher rates of acute complications.
OBJECTIVE:The aim was to test the hypothesis that acute intravenous cocaine administration can cause coronary microvascular constriction culminating in myocardial ischaemia and cardiogenic shock.METHODS:Systemic haemodynamic variables and coronary blood flow were measured in 14 Yorkshire swine at baseline and following intravenous administration of 1, 3, and 10 mg.kg-1 of cocaine. Epicardial coronary artery diameter was measured from coronary arteriograms and coronary flow velocity was recorded with a Doppler flow wire.RESULTS:Cocaine produced a decrease in mean arterial pressure (65%), cardiac output (80%), and stroke volume (80%), and an increase in pulmonary artery diastolic pressure (60%). Although coronary blood flow decreased by 70%, epicardial coronary cross sectional area decreased by only 37-45%. Pretreatment with prazosin did not abolish the decrease in coronary blood flow. After administration of 10 mg.kg-1 of cocaine, five of 14 animals developed myocardial ischaemia and cardiogenic shock, culminating in ventricular fibrillation and death.CONCLUSIONS:In anaesthetised Yorkshire swine, cumulative intravenous doses of cocaine caused a significant reduction in coronary blood flow resulting in myocardial ischaemia, which cannot be attributed to epicardial vasoconstriction alone. This suggest that cocaine-induced coronary ischaemia may result from microvascular constriction, which is only partially prevented by alpha 1 blockade. In addition, direct toxic effects of cocaine on the myocardium may also contribute to the development of cardiogenic shock.
Traditional binary definitions of coronary restenosls based on 6-month continuous angiographic measurements (e.g., >50% diameter stenosis) may give confusing results for lesions whose late percent stenosis falls near the arbitrary threshold. To determine the long-term clinical consequences of such lesions, the overall correlation between follow-up percent stenosis and the performance of subsequent ischemia-driven target vessel revascularization (triggered by significant angina or a positive exercise study result, or both) was examined in 443 consecutive lesions treated with directional coronary atherectomy or Palmaz-Schatz coronary stenting. Follow-up angiograms (available in 355 lesions, 82%) were stratified into 3 groups: severe late stenosis (>70% stenosis, n = 59), moderate late stenosis (40% to 70% stenosis, n = 72), and minimal late stenosis (<40% stenosis, n = 224). With an average clinical follow-up of 933 ± 394 days, 92% of lesions In the "severe late stenosis" group were treated with ischemia-driven target vessel revascularization, compared with 0% of the lesions in the "minimal late stenosis" group. Ischemia-driven target vessel revascularization was performed in 38% of patients in the "moderate late stenosis" group. However, patiente in this group who did not undergo revascularization (despite the fact that 43% of them had a late stenosis of >50%) showed a similarly favorable long-term clinical outcome to patiente with a minimal late stenosis. These results support a strategy of conservative management for the 20% of patiente who have a moderate (40% to 70%) late stenosis after stenting or atherectomy, but do not have evidence of ischemia.
OBJECTIVES:This study was designed to assess the relative contributions of intimal hyperplasia and stent compression to the lumen narrowing seen after intracoronary stenting and to determine whether the lumen enlargement produced by angioplasty of in-stent restenosis results primarily from compression or extrusion of intimal hyperplasia through the stent or from additional stent expansion. BACKGROUND:Palmaz-Schatz stent placement outwardly displaces plaque and eliminates elastic vessel recoil to provide a large and smooth lumen. Some degree of late lumen narrowing occurs within each stent and causes significant restenosis (> or = 50% stenosis) in 25% to 30% of treated lesions. It has not been clear, however, whether this narrowing results from stent compression (crush) or from in-stent intimal hyperplasia. Because the Palmaz-Schatz stent has a distinct radiographic shadow, it is possible to determine the late diameter of both the stent and the enclosed vessel lumen to assess the relative contributions of these two processes. METHODS:From cineangiograms, initial (after stenting) and late (follow-up) lumen and stent diameters were examined in 55 patients (59 stents, group I) who had both immediate and 6-month (192 +/- 117 days) angiography. Lumen and stent diameter were also examined before and after dilation in 30 patients (30 stents, group II) who underwent angioplasty of severe in-stent restenosis. RESULTS:Late loss in minimal lumen diameter was 0.99 +/- 0.87 mm for group I despite only a slight (0.03 +/- 0.23-mm) reduction in the corresponding stent diameter. After redilation for in-stent restenosis, the acute gain in minimal lumen diameter was 1.51 +/- 0.82 mm for group II, again without appreciable increase (0.06 +/- 0.20 mm) in stent diameter. CONCLUSIONS:Restenosis after intracoronary Palmaz-Schatz stenting appears to be due predominantly to lumen encroachment by intimal hyperplasia within the stent, with minimal contribution of stent compression. Lumen enlargement after coronary angioplasty of in-stent restenosis appears to be due primarily to compression or extrusion of intimal hyperplasia through the stent, or both, rather than to further stent expansion.
This study investigates whether adjunctive balloon angioplasty can be safely used to improve acute results in cases where directional coronary atherectomy alone has provided a successful (but suboptimal) outcome. Between October 1, 1990, and October 1, 1992, directional coronary atherectomy was performed successfully in 198 of 228 lesions. Individual operators believed that most acute results were satisfactory after atherectomy alone (group I, n = 115) with a minimal lumen diameter that increased from 0.82 +/- 0.45 to 3.21 +/- 0.65 mm after atherectomy, for an acute gain in lumen diameter of 2.39 +/- 0.73 mm and a residual stenosis of 6 +/- 13%. In 42% of lesions (group II, n = 83), however, results were considered suboptimal after atherectomy alone, with a minimal lumen diameter that increased from 0.85 +/- 0.45 to 2.83 +/- 0.64 mm, a smaller acute gain of 1.96 +/- 0.72 mm, and a mean residual stenosis of 17 +/- 14% (although all residual stenoses were < 50%, 19% had a residual stenosis > 30%). Adjunctive balloon angioplasty in these group II lesions provided an additional gain of 0.34 +/- 0.38 mm, bringing the total acute gain for group II lesions to 2.32 +/- 0.78 mm and the residual stenosis to 9 +/- 13%, similar to that of group I patients who underwent atherectomy alone. This strategy resulted in a 7 +/- 13% overall residual stenosis for the study population, with no higher incidence of periprocedural complications or adverse late clinical outcomes in group II patients.(ABSTRACT TRUNCATED AT 250 WORDS)