Randomized, double-blind, multicenter study of the Endeavor zotarolimus-eluting phosphorylcholine-encapsulated stent for treatment of native coronary artery lesions. Clinical and angiographic results of the ENDEAVOR II Trial.

AIM: The use of the Endeavor stent might reduce restenosis and stent thrombosis at 9 months. METHODS: Patients (n =1,197) treated for single coronary artery stenosis were enrolled in a prospective, randomized, double-blind study and randomly assigned to receive the Endeavor zotarolimus-eluting phosphorylcholine polymer-coated stent (n= 598) or the same bare metal stent but without the drug or the polymer coating (n=599). RESULTS: The 2 groups were well matched in baseline characteristics. Diabetes was present in 20.1% of patients; the mean reference vessel diameter was 2.75 mm; and the mean lesion length was 14.2 mm. The primary end point of target vessel failure at 9 months was reduced from 15.1% with the bare metal stent to 7.9% with the Endeavor (P=0.0001), and the rate of major adverse cardiac events was reduced from 14.4% with the bare metal stent to 7.3% with the Endeavor (P=0.0001). Target lesion revascularization was 4.6% with Endeavor compared with 11.8% with the bare metal stent (P=0.0001). The rate of stent thrombosis was 0.5% with the Endeavor, which was not significantly different from 1.2% with the bare metal stent. In 531 patients submitted to angiographic follow-up, late loss was reduced from 1.03+/-0.58 to 0.61+/-0.46 (P<0.001) in stent and from 0.72+/-0.61 to 0.36+/-0.46 (P<0.001) in segment. The rate of in-segment restenosis was reduced from 35% to 13.2% with Endeavor (P<0.0001). There was no excessive edge stenosis, aneurysm formation, or late acquired malposition by intravascular ultrasound imaging. Differences in clinical outcome were maintained at 12 and 24 months (P<0.0001). CONCLUSIONS: Compared with bare metal stents, the Endeavor stent is safe and reduces the rates of clinical and angiographic restenosis at 9, 12, and 24 months.

Experimental biharzial bladder cancer: tryptophan metabolism in nonhuman primates experimentally infected with Schistosoma haematobium.

A nonhuman primate species infected with Schistosoma haematobium provided a model system for controlled studies on biharzial bladder cancer. Urinary excretion of tryptophan metabolites by capuchin monkeys (Cebus apella) was similar to that of humans when expressed per g creatinine. Liver tryptophan oxygenase activity of the capuchin monkeys was comparable to that of humans. Excretion of 3-hydroxykynurenine and 3-hydroxyanthranilic acid was elevated above control levels in capuchin monkeys infected experimentally with S. haematobium. The capuchin-S. haematobium system closely resembles the human biharziasis system and offers a reproducible laboratory model system for the controlled study of the parasitology, pathogenesis, and biochemistry of biharzial bladder cancer.

Proliferative epithelial lesions of the urinary bladder in cynomolgus monkeys (Macaca fascicularis) infected with Schistosoma intercalatum.

Five cynomolgus monkeys (Macaca fascicularis) were infected with Schistosoma intercalatum, a helminth that is morphologically similar to Schistosoma haematobium. Infections were readily established and remained active until the monkeys were sacrificed 21 to 84 weeks after exposure. Although the schistosomes were located predominantly in mesenteric and hepatic portal venules, schistosome eggs were found in the bladders of 3 monkeys. Nodules of atypical epithelial cells interpreted as superficially infiltrating undifferentiated bladder carcinomas were found in one monkey 23 weeks after infection. These sessile tumors differ strikingly from the well-differentiated, papillary transitional cell tumors previously reported from several species of experimental animals infected with S. haematobium. The tumors are also dissimilar to the squamous cell bladder tumors associated with S. haematobium infection in man but may nonetheless be useful for investigations of schistosomal bladder cancer.

Natural history of papillary lesions of the urinary bladder in schistosomiasis.

Variable epithelial hyperplasia was observed in urinary bladder of nine capuchin monkeys (Cebus apella) when examined at cystotomy 94 to 164 weeks after infection with Schistosoma haematobium. These hosts were followed for 24 to 136 weeks postcystotomy to determine the status of bladder lesions in relation to duration of infection and to ascertain whether lesion samples removed at cystotomy reestablished themselves in autologous and heterologous transfers. There was involution of urothelial hyperplasia in eight of nine animals and no evidence for establishment of transplanted bladder lesions.

Impact of smoking on clinical and angiographic restenosis after percutaneous coronary intervention: another smoker's paradox?

BACKGROUND: Recent studies have suggested that smokers may require less frequent repeated revascularization after percutaneous coronary intervention (PCI) compared with nonsmokers. However, the mechanism of this phenomenon is unknown. METHODS AND RESULTS: We examined the association between smoking and restenosis using pooled data from 8671 patients treated with PCI in 9 multicenter clinical trials. Clinical restenosis was examined in the cohort of 5682 patients who were assigned to clinical follow-up only. Angiographic restenosis was evaluated in the subset of 2989 patients who were assigned to mandatory angiographic restudy. Among those patients assigned to clinical follow-up only, target lesion revascularization (TLR) occurred in 6.6% of smokers and 10.1% of nonsmokers (P<0.001). After adjustment for baseline clinical and angiographic differences, the rate of TLR remained significantly lower in smokers with an adjusted relative risk of 0.69 (95% CI, 0.54 to 0.88). Among the angiographic cohort, there were no differences in the rates of angiographic restenosis or follow-up diameter stenosis in either univariate or multivariate analyses. This dissociation between clinical and angiographic restenosis was explained in part by reduced sensitivity to restenosis on the part of smokers and by the greater reluctance of smokers to seek medical attention despite recurrent angina. CONCLUSIONS: In patients undergoing contemporary PCI, cigarette smoking is associated with a lower rate of subsequent TLR without affecting angiographic restenosis. These findings have important implications for the follow-up of smokers after PCI and suggest that cross-study comparisons of rates of clinical restenosis must account for the potential confounding effect of smoking.

Impact of smoking on health-related quality of life after percutaneous coronary revascularization.

BACKGROUND: PTCA is performed primarily to improve health-related quality of life (HRQOL) in patients with symptomatic coronary artery disease. In patients undergoing PTCA, smoking has been shown to increase risks of late myocardial infarction and death. Whether smoking also affects HRQOL after PTCA is currently unknown. METHODS AND RESULTS: We examined the relation between smoking status and HRQOL among 1432 patients who underwent PTCA as part of 2 multicenter clinical trials. HRQOL was assessed with the use of the Medical Outcomes Study SF-36 questionnaire. Patients were classified as smokers (n=301), quitters (n=141), or nonsmokers (n=990) on the basis of their smoking status at the time of their index procedure and during the first year of follow-up. For the overall population, HRQOL improved significantly after PTCA for all scales except general health perception, with improvements ranging from 5.5 points for mental health to 23.2 points for role-physical functioning. After adjustment for baseline characteristics and initial HRQOL, nonsmokers had gains at 6 months that were larger than those of smokers for all health domains: physical function (15.4 versus 10.4 points), role-physical (24.5 versus 13.9), pain (18.4 versus 13.3), general health perception (1.7 versus -4.5), vitality (11.0 versus 4. 7), social function (12.8 versus 3.5), role-emotional (13.5 versus 6. 7), and mental health (6.8 versus 0.8; P:<0.02 for all comparisons). Quitters had 6-month HRQOL improvements that were greater than those in smokers for all domains as well. Findings were similar at 1 year. CONCLUSIONS: Quality-of-life benefits of PTCA are diminished by continued smoking. Efforts to promote smoking cessation at the time of PTCA may substantially improve the health outcomes of these procedures.

Immediate and late clinical outcomes of carotid artery stenting in patients with symptomatic and asymptomatic carotid artery stenosis: a 5-year prospective analysis.

BACKGROUND: Carotid stenting is a less invasive percutaneous procedure than carotid endarterectomy for the treatment of carotid stenosis. Reports suggest that it can be performed with periprocedural complication rates similar to those of carotid endarterectomy. The purpose of this study was to determine short- and long-term outcomes in the largest prospective cohort of carotid stenting patients. METHODS AND RESULTS: This study followed 528 consecutive patients (604 hemispheres/arteries) undergoing carotid stenting. There was a 0.6% (n=3) fatal stroke rate and 1% (n=5) nonstroke death rate at 30 days. The major stroke rate was 1% (n=6), and the minor stroke rate was 4.8% (n=29). The overall 30-day stroke and death rate was 7.4% (n=43). Over the 5-year study period, the 30-day minor stroke rate improved from 7.1% (n=7) for the first year to 3.1% (n=5) for the fifth year (P:<0.05 for trend). The best predictor of 30-day stroke and death was age >/=80 years. After the 30-day period, the incidence of fatal and nonfatal stroke was 3.2% (n=31). On Kaplan-Meier analysis, the 3-year freedom from ipsilateral or fatal stroke was 92+/-1%. CONCLUSIONS: Experience from a single group of operators demonstrates that carotid stenting can be performed with an acceptable 30-day complication rate. Late follow-up also demonstrates a low rate of fatal and nonfatal stroke. These results suggest that carotid stenting may be comparable to carotid endarterectomy, and it underscores the clinical equipoise and premise for the National Institute of Health-supported, randomized Carotid Revascularization Endarterectomy Versus Stent Trial comparing carotid stenting with carotid endarterectomy.

Short- and intermediate-term clinical outcomes from direct myocardial laser revascularization guided by biosense left ventricular electromechanical mapping.

BACKGROUND: Direct myocardial revascularization (DMR) has been examined as an alternative treatment for patients with chronic refractory myocardial ischemic syndromes who are not candidates for conventional coronary revascularization. Methods and Results-We used left ventricular electromagnetic guidance in 77 patients with chronic refractory angina (56 men, mean age 61+/-11 years, ejection fraction 0.48+/-0.11) to perform percutaneous DMR with an Ho:YAG laser at 2 J/pulse. Procedural success (laser channels placed in prespecified target zones) was achieved in 76 of 77 patients with an average of 26+/-10 channels (range 11 to 50 channels). The rate of major in-hospital cardiac adverse events was 2.6%, with no deaths or emergency operations, 1 patient with postprocedural pericardiocentesis, and 1 patient with minor embolic stroke. The rate of out-of-hospital adverse cardiac events (up to 6 months) was 2.6%, with 1 patient with myocardial infarction and 1 patient with stroke. Exercise duration after DMR increased from 387+/-179 to 454+/-166 seconds at 1 month and to 479+/-161 seconds at 6 months (P=0.0001). The time to onset of angina increased from 293+/-167 to 377+/-176 seconds at 1 month and to 414+/-169 seconds at 6 months (P=0.0001). Importantly, the time to ST-segment depression (>/=1 mm) also increased from 327+/-178 to 400+/-172 seconds at 1 month and to 436+/-175 seconds at 6 months (P=0.001). Angina (Canadian Cardiovascular Society classification) improved from 3.3+/-0.5 to 2.0+/-1.2 at 6 months (P<0.001). Nuclear perfusion imaging studies with a dual-isotope technique, however, showed no significant improvements at 1 or 6 months. CONCLUSIONS: Percutaneous DMR guided by left ventricular mapping is feasible and safe and reveals improved angina and prolonged exercise duration for up to a 6-month follow-up.

Stent thrombosis in the modern era: a pooled analysis of multicenter coronary stent clinical trials.

BACKGROUND: There are limited studies of stent thrombosis in the modern era of second-generation stents, high-pressure deployment, and current antithrombotic regimens. METHODS AND RESULTS: Six recently completed coronary stent trials and associated nonrandomized registries that enrolled 6186 patients (6219 treated vessels) treated with >/=1 coronary stent followed by antiplatelet therapy with aspirin and ticlopidine were pooled for this analysis. Within 30 days, clinical stent thrombosis developed in 53 patients (0.9%). The variables most significantly associated with the probability of stent thrombosis were persistent dissection NHLBI grade B or higher after stenting (OR, 3.7; 95% CI, 1.9 to 7.7), total stent length (OR, 1.3; 95% CI, 1.2 to 1.5 per 10 mm), and final minimal lumen diameter within the stent (OR, 0.4; 95% CI, 0.2 to 0.7 per 1 mm). Stent thrombosis was documented by angiography in 45 patients (0.7%). Clinical consequences of angiographic stent thrombosis included 64.4% incidence of death or myocardial infarction at the time of stent thrombosis and 8.9% 6-month mortality. CONCLUSIONS: Stent thrombosis occurred in <1.0% of patients undergoing stenting of native coronary artery lesions and receiving routine antiplatelet therapy with aspirin plus ticlopidine. Procedure-related variables of persistent dissection, total stent length, and final lumen diameter were significantly associated with the probability of stent thrombosis. Continued efforts to eliminate this complication are warranted given the serious clinical consequences.

Randomized comparison of GR-II stent and Palmaz-Schatz stent for elective treatment of coronary stenoses.

BACKGROUND: This prospective multicenter randomized clinical trial was designed to evaluate the long-term angiographic and clinical outcomes of elective treatment with the GR-II stent compared with the Palmaz-Schatz (PS) stent in patients with coronary stenoses. METHODS AND RESULTS: Seven hundred fifty-five patients with myocardial ischemia and de novo native coronary stenoses in 3- to 4-mm vessels were randomly assigned to the PS (375 patients) or the GR-II stent (380 patients). The primary end point was 12-month target lesion revascularization (TLR)-free survival. Angiography was performed at baseline and at follow-up in the first 300 consecutive patients to assess the frequency of angiographic restenosis. Procedure success was 98.5% for the GR-II stent and 99.4% for the PS stent (P:=0.19). At 30 days, patients assigned to the GR-II stent had a higher stent thrombosis rate (3.9% versus 0.3% for PS stent, P:<0.001) and TLR rate (3.9% versus 0.5% for PS stent, P:<0.001). The GR-II group had a higher follow-up restenosis frequency (47.3% versus 20.6% for the PS group, P:<0.001) and a lower 12-month TLR-free survival rate (71.7% versus 83.9% for the PS group, P:<0. 001). Multivariate logistic regression analysis identified a smaller final stent minimal lumen diameter (odds ratio [OR] 2.49, 95% CI 1. 56 to 3.98; P:<0.001), diabetes mellitus (OR 2.14, 95% CI 1.42 to 3. 22; P:<0.001), and use of the GR-II stent (OR 1.78, 95% CI 1.20 to 2. 64; P:<0.01) as independent determinants of 12-month TLR. CONCLUSIONS: On the basis of these long-term follow-up data, we conclude that use of the GR-II stent should be limited to the acute treatment of abrupt or threatened closure after failed conventional balloon angioplasty procedures.

Final results of the Can Routine Ultrasound Influence Stent Expansion (CRUISE) study.

BACKGROUND: Intravascular ultrasound (IVUS) can assess stent geometry more accurately than angiography. Several studies have demonstrated that the degree of stent expansion as measured by IVUS directly correlated to clinical outcome. However, it is unclear if routine ultrasound guidance of stent implantation improves clinical outcome as compared with angiographic guidance alone. METHODS AND RESULTS: The CRUISE (Can Routine Ultrasound Influence Stent Expansion) study, a multicenter study IVUS substudy of the Stent Anti-thrombotic Regimen Study, was designed to assess the impact of IVUS on stent deployment in the high-pressure era. Nine centers were prospectively assigned to stent deployment with the use of ultrasound guidance and 7 centers to angiographic guidance alone with documentary (blinded) IVUS at the conclusion of the procedure. A total of 525 patients were enrolled with completed quantitative coronary angiography, quantitative coronary ultrasound, and clinical events adjudicated at 9 months for 499 patients. The IVUS-guided group had a larger minimal lumen diameter (2.9+/-0.4 versus 2.7+/-0. 5 mm, P<0.001) by quantitative coronary angiography and a larger minimal stent area (7.78+/-1.72 versus 7.06+/-2.13 mm(2), P<0.001) by quantitative coronary ultrasound. Target vessel revascularization, defined as clinically driven repeat interventional or surgical therapy of the index vessel at 9 month-follow-up, occurred significantly less frequently in the IVUS-guided group (8.5% versus 15.3%, P<0.05; relative reduction of 44%). CONCLUSIONS: These data suggest that ultrasound guidance of stent implantation may result in more effective stent expansion compared with angiographic guidance alone.

Generalized model of restenosis after conventional balloon angioplasty, stenting and directional atherectomy.

OBJECTIVES: This study was designed to extend the results of a quantitative model originally developed for restenosis after stenting or atherectomy to include restenosis after conventional balloon angioplasty. BACKGROUND: We have previously described a continuous regression model that explains late (6-month) lumen narrowing as the difference between the immediate gain and the subsequent normally distributed late loss in lumen diameter after Palmaz-Schatz stenting or directional atherectomy. METHODS: Lumen diameter was measured immediately before and after coronary intervention on 524 consecutive lesions including those treated by Palmaz-Schatz stenting (102), directional atherectomy (134) and conventional balloon angioplasty (288). Of these lesions, 475 (91%) underwent follow-up angiography 3 to 6 months after treatment. The immediate increase in lumen diameter produced by the intervention (immediate gain) and the subsequent reduction in lumen diameter between the time of intervention to follow-up angiography (late loss) were examined. Association between demographic or angiographic variables and continuous measures of restenosis (late lumen diameter or late percent stenosis) was tested with linear regression techniques; a traditional binary measure of restenosis (late diameter stenosis > or = 50%) was evaluated with logistic regression analysis. RESULTS: Regression models relating late lumen diameter to the immediate lumen result were successfully fitted to all segments studied. According to these models, three indexes of restenosis (late lumen diameter, late percent stenosis and binary restenosis) were found to depend solely on the immediate lumen diameter after the procedure and the immediate residual percent stenosis, but not on the specific intervention used. Moreover, the late loss in lumen diameter was found to vary directly with the immediate gain provided by an intervention, and the "loss index" (a measure that corrects for differences in immediate gain) was uniform among all three interventions. CONCLUSIONS: The quantitative model originally developed for restenosis after stenting or atherectomy may thus be generalized to include conventional balloon angioplasty. It shows that the apparent differences in restenosis among the three interventions studied are due solely to differences in the immediate result provided and not to differences in the behavior of subsequent late loss. Moreover, although the late loss in lumen diameter was found to correlate with differences in the immediate gain provided by an intervention, the "loss index" (a measure that corrects for differences in acute gain) was uniform across all three interventions. It is thus the immediate result (and not the procedure used to obtain that result) that determines late outcome after coronary intervention.

Intracardiac thrombus causing peritoneovenous shunt failure: detection by two-dimensional echocardiography.

Peritoneovenous shunts have become an accepted mode of therapy for ascites refractory to medical treatment. However, their use is known to be associated with significant morbidity and mortality. Reported is the case of a patient with a Denver shunt who developed massive intracardiac thrombosis and subsequent shunt malfunction, despite preserved shunt patency.

Long-term (4- to 6-year) outcome of Palmaz-Schatz stenting: paucity of late clinical stent-related problems.

OBJECTIVES: The purpose of this prospective single-center study was to evaluate the longer-term outcome of Palmaz-Schatz stenting in the treatment of native coronary and saphenous vein bypass graft disease. BACKGROUND: The STRESS (Stent Restenosis Study) and BENESTENT (Belgian Netherlands Stent) trials have demonstrated a decrease in both angiographic restenosis and the need for repeat revascularization in the 1st year for vessels treated by stenting rather than balloon angioplasty. Longer-term (1 to 5 years) clinical results of Palmaz-Schatz stenting are not yet well established. Late migration of the stent, metal fatigue, endarteritis and late restenosis have all been proposed as potential late clinical complications of coronary stent implantation. METHODS: The study cohort consisted of 175 consecutive patients who underwent elective placement of 194 Palmaz-Schatz stents in 185 vessels. Clinical events (death, myocardial infarction, recurrent angina or any revascularization) were assessed at 6 weeks, 2, 4 and 6 months, 1 year and yearly thereafter. Clinical follow-up was available on all patients at a mean +/- SD of 54 +/- 17 months. RESULTS: Angiographic success was achieved in 173 patients (98.9%); angiographic restenosis was observed at 6 months in 26.1% of target sites. The survival rate was 86.7% at 5 years, with a 5-year event-free survival rate decreasing progressively to 50.7%, reflecting primarily repeat revascularization procedures (41.2% at 5 years). However, the rate of repeat revascularization of the treatment site (target site revascularization [TSR]) was 14.4%, 17.7% and 19.8% at 1, 3 and 5 years, respectively, with late (> 1 year) TSR driven by in-stent restenosis in only 3 patients (1.7%). Rates of both 5-year survival (70.5% vs. 93.4%) and event-free survival (21.1% vs. 63.3%) were lower for patients who underwent saphenous vein graft (SVG) stenting than for those with native coronary artery stenting. However, 5-year TSR rates were similar for SVGs (21.9%) and native vessels (19.2%), indicating that the higher incidence of repeat revascularization for SVGs was due to an increase in non-TSR, driven by progressive disease at other sites. CONCLUSIONS: The long-term outcome of stenting shows stability of the treated lesion, with only a slight increase in TSR between 2 and 5 years (17.1% to 19.8%). The progressive increase in repeat revascularization over that period (24% to 41%) and most ongoing late events can be attributed to the progression of coronary disease at other sites, rather than to late deterioration of the stent result itself. Such non-TSR events account for the majority of clinical events in the patients who underwent SVG stenting.

Analysis of late lumen narrowing after excimer laser-facilitated coronary angioplasty.

OBJECTIVES: The purpose of this study was to analyze the quantitative angiographic factors affecting restenosis after excimer laser-facilitated coronary angioplasty. BACKGROUND: Restenosis after balloon angioplasty, directional atherectomy and coronary stenting has been analyzed using both dichotomous (> or = 50% diameter stenosis) and continuous (late lumen narrowing) end points, leading to the conclusion that achieving a large lumen diameter at the time of the procedure is associated with a lower risk of angiographic restenosis. METHODS: Quantitative angiographic measurements were made before treatment, after laser angioplasty, after adjunctive balloon angioplasty and at 6-month angiographic follow-up in 168 patients with 179 treated lesions. RESULTS: The immediate increase in lumen diameter (total acute gain 1.45 +/- 0.71 mm [mean +/- SD]) was due to the combination of laser treatment (0.79 +/- 0.61 mm) and subsequent adjunctive balloon angioplasty (0.66 +/- 0.55 mm). At follow-up, the minimal lumen diameter had decreased (late loss 0.71 +/- 0.84 mm), yielding an overall restenosis rate of 50% (defined dichotomously by > or = 50% diameter stenosis). Multivariable regression analyses showed that restenosis was related to vessel diameter, as well as minimal lumen diameter, achieved immediately after the procedure. CONCLUSIONS: Although the restenosis rates for the small vessels typically treated with excimer laser angioplasty were high, the lowest restenosis rates were seen in large vessels with the largest postprocedural minimal lumen diameters. The goal of this procedure should be to safely achieve the largest lumen possible with the combination of laser treatment and adjunctive balloon dilation.

Mechanisms of restenosis and redilation within coronary stents--quantitative angiographic assessment.

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.

Laser balloon angioplasty: clinical, angiographic and histologic results.

Laser balloon angioplasty combines conventional coronary angioplasty with laser energy to transiently heat vascular tissue. Laser balloon angioplasty, was performed in 21 patients (aged 56 +/- 13 years), including 10 patients treated urgently after acute failure of conventional angioplasty and 11 patients treated with elective laser balloon angioplasty. Immediately after conventional angioplasty, laser doses (1 to 10 doses of 205 to 380 J each) were delivered during inflation of the laser balloon to a pressure of 4 atm. Seven (70%) of 10 patients with acute failure of conventional angioplasty were successfully treated with laser balloon angioplasty, but 3 (30%) were unsuccessfully treated with the laser procedure and required emergency coronary artery bypass surgery. In all three failures, the 3 mm laser balloon angioplasty catheter was not the optimal size for the vessel. In the 11 patients treated with elective laser balloon angioplasty (reference diameter 2.94 +/- 0.22 mm), the minimal luminal diameter increased from 0.45 +/- 0.25 to 1.85 +/- 0.46 mm after conventional angioplasty and to 2.44 +/- 0.29 mm after laser balloon angioplasty (p less than 0.001). This corresponded to a decrease in diameter stenosis from 84 +/- 9% before to 35 +/- 16% after conventional angioplasty and to 15 +/- 10% after laser balloon angioplasty (p less than 0.001). There were no instances of myocardial infarction, emergency coronary artery bypass surgery or death and no acute complications related to delivery of laser energy in this group. Follow-up coronary angiography was performed 5.5 +/- 1.1 months after laser balloon angioplasty in 18 patients discharged from the hospital after a successful procedure. Ten patients (56%) had angiographic restenosis, defined as recurrent diameter stenosis greater than 50%. Six patients were subsequently treated by directional coronary atherectomy, which revealed intimal proliferation indistinguishable from that in patients with restenosis after conventional angioplasty. In conclusion, laser balloon angioplasty may be effective in sealing severe coronary dissections and reversing abrupt closure associated with failed conventional angioplasty. After uncomplicated conventional angioplasty, laser balloon angioplasty improves immediate luminal dimensions, but restenosis appears to be mediated by intimal hyperplasia, similar to that seen after conventional angioplasty.

Economics of elective coronary revascularization. Comparison of costs and charges for conventional angioplasty, directional atherectomy, stenting and bypass surgery.

OBJECTIVES: This study was designed to evaluate more closely the true in-hospital costs of elective revascularization by directional coronary atherectomy and intracoronary stenting and to compare these costs with those of the traditional revascularization alternatives (i.e., conventional balloon angioplasty and coronary artery bypass surgery). BACKGROUND: Previous studies have suggested that total hospital charges for directional coronary atherectomy or intracoronary stenting are significantly higher than those for conventional angioplasty. However, hospital charges do not necessarily reflect true economic costs, and their use may provide misleading data with regard to cost-effectiveness. METHODS: We analyzed in-hospital charges from the itemized hospital accounts of 300 patients undergoing elective angioplasty, directional atherectomy, Palmaz-Schatz coronary stenting or bypass surgery between January 1, 1990 and December 31, 1991. Costs were then derived by adjusting itemized patient accounts for department-specific cost/charge ratios. Catheterization laboratory costs were based on actual resource consumption, and daily room costs were adjusted for the intensity of nursing services provided. RESULTS: Length of hospital stay was similar for atherectomy (2.3 +/- 1.5 days) and conventional angioplasty (2.6 +/- 1.7 days) but significantly longer for stenting (5.5 +/- 2.6 days, p < 0.05). Total costs were also significantly higher for coronary stenting ($7,878 +/- $3,270, median $6,699, p < 0.05) than for angioplasty ($5,396 +/- $2,829, median $4,753) or atherectomy ($5,726 +/- $2,716, median $4,986). However, length of stay, resource consumption (laboratory and radiologic testing, drugs, blood products, for example) and total costs for bypass surgery were still greater than for any of the percutaneous interventional procedures. CONCLUSIONS: In contrast to previous studies utilizing only hospital charges, the in-hospital costs of angioplasty and directional coronary atherectomy were similar. Although the cost of coronary stenting was approximately $2,500 higher than that of conventional angioplasty, the magnitude of this difference was smaller than the $6,300 increment previously suggested on the basis of analysis of hospital charges. These findings reflect the inherent discrepancies between cost-based and charge-based methodologies and may have important implications for future studies evaluating the relative cost-effectiveness of newer coronary interventions.

Long-term results of directional coronary atherectomy: predictors of restenosis.

OBJECTIVES: This study was performed to obtain better understanding of the long-term clinical efficacy of directional coronary atherectomy. BACKGROUND: Although this procedure yields favorable acute results, its acceptance has been limited by the perception that late results (that is, freedom from restenosis) are no better than those of conventional angioplasty. METHODS: A total of 225 atherectomies performed in 190 patients between August 1988 and July 1991 were examined. Minimal lumen diameter of the treated segments was measured on angiograms obtained before, after and 6 months after intervention. RESULTS: Although most lesions (97%) had one or more characteristics predictive of unfavorable short- or long-term results after conventional angioplasty, atherectomy was successful in 205 lesions (91%) with a mean residual stenosis of 7 +/- 16%. After subsequent balloon angioplasty in 16 unsuccessful atherectomy attempts, procedural success was 98%. There were no deaths or Q wave myocardial infarctions, and one patient (0.5%) underwent emergency bypass surgery. Six-month angiographic follow-up was obtained in 77% of the eligible patients. The overall angiographic restenosis rate was 32%. Predictors of a lower restenosis rate included a postprocedure lumen diameter > 3 mm (24% vs. 39%, p = 0.047), serum cholesterol < or = 200 mg/dl (18% vs. 40%, p = 0.018) and recent myocardial infarction (16% vs. 37%, p = 0.034). Life-table analysis showed a 2% mortality rate and a 26% incidence of other events (myocardial infarction, repeat revascularization) within the 1st year. The annual 5% mortality rate and 7% incidence of other events during years 2 and 3 were related in large part to the existence or progression of disease at other locations. CONCLUSIONS: Six-month angiographic follow-up of patients who underwent directional coronary atherectomy during the 1st 3 years of our experience shows an overall restenosis rate of 32%, with lower rates in patients with a postatherectomy lumen diameter > or = 3 mm, cholesterol level < or = 200 mg/dl or a recent myocardial infarction. Few if any events relating to the site of atherectomy developed after the 1st year of follow-up.

Novel approach to the analysis of restenosis after the use of three new coronary devices.

Restenosis after coronary intervention has remained a vexing problem despite the introduction of nearly 24 newer coronary interventional devices. To more clearly evaluate the potential impact of three such new devices on restenosis, coronary lumen diameters were measured before, immediately after and at 6 months after intervention, and restenosis was analyzed using continuous geometric techniques. Lumen diameters were measured before and immediately after intervention in 223 coronary vessels treated with one of three new devices: a single Palmaz-Schatz stent (n = 87), directional atherectomy (n = 125) and laser balloon angioplasty (n = 11); 184 (83%) of the patients underwent follow-up angiography 6 months after treatment. The immediate increase in lumen diameter produced by the intervention (acute gain) and the subsequent reduction in lumen diameter between the time of intervention to 6 month follow-up study (late loss) were examined. For each of the three interventions, the restenosis rate at follow-up study was analyzed using a traditional dichotomous definition (greater than or equal to 50% diameter stenosis), as well as a novel graphic technique. Although the apparent restenosis rates differed significantly among the three interventions (19% for stents, 31% for atherectomy and 50% for laser balloon angioplasty; p = 0.02), late loss among the three interventions was equivalent (average 1 mm; p = 0.91). There were, however, marked differences in the acute gain achieved by the three interventions: 2.6 mm for stents, 2.2 mm for atherectomy and 2 mm for laser balloon angioplasty; p less than 0.001). It was these differences in acute gain rather than late loss that explained the observed differences in restenosis rate.(ABSTRACT TRUNCATED AT 250 WORDS)