Cytochrome P450 2E1 mRNA in the rat prostate: detection and quantitation by competitive reverse transcription and polymerase chain reaction

Conventional balloon angioplasty treatment of aorto-ostial stenoses in native coronary arteries and saphenous vein grafts is associated with a low primary success rate, a high complication rate and a high incidence of restenosis. The short-term outcome of Palmaz-Schatz stent implantation in aorto-ostial lesions was compared with that of balloon angioplasty. Thirteen patients underwent stent implantation for 13 de novo lesions (four in the left main coronary trunk, two in the right coronary artery, seven in the vein graft) between January 1994 and December 1995. Fourteen patients underwent balloon angioplasty for 14 de novo lesions (five in the left main coronary trunk, four in the right coronary artery, five in the vein graft between January 1986 and April 1992. Both groups had similar clinical characteristics. Initial success was obtained in all patients in the stent group, compared with 71% of the balloon angioplasty group. Insufficient dilation was the main cause for such failure in the balloon angioplasty group. Baseline reference diameters were similar (3.40 +/- 0.65 mm in the stent group vs 3.36 +/- 0.42 mm in the balloon angioplasty group) and there was no difference in baseline minimal luminal diameter (1.41 +/- 0.74 vs 1.08 +/- 0.56 mm). Minimal luminal diameter was significantly greater in the stent group than in the balloon angioplasty group at both post-procedure and follow-up examinations (post: 3.36 +/- 0.58 vs 2.69 +/- 0.45 mm, p < 0.01; follow-up: 2.33 +/- 0.96 vs 1.52 +/- 0.68 mm, p < 0.05). There was no subacute occlusion in either group. The overall angiographic restenosis rate (> 50% stenosis) was lower in the stent group (17%) than in the balloon angioplasty group: the restenosis rates of native lesions were 0% in the stent group and 40% in the balloon angioplasty group; those of saphenous vein graft lesions were 33% in the stent group and 50% in the balloon angioplasty group. Although the number of patients was limited, these results suggest that Palmaz-Schatz stent implantation may be a safe and effective strategy for treating aorto-ostial lesions in both native coronary arteries and saphenous vein grafts.     

Radiofrequency thermal balloon coronary angioplasty: a new device for successful percutaneous transluminal coronary angioplasty

OBJECTIVES: The purpose of this study was to evaluate the effects of thermal balloon percutaneous transluminal coronary angioplasty using radiofrequency energy in the treatment of patients with failed coronary angioplasty and complex lesions. In addition, we evaluated restenosis after radiofrequency thermal balloon applications. BACKGROUND: The efficacy of coronary angioplasty is limited by the relatively low success rate in complex lesions and the high frequency of restenosis. Few reports have studied the combined effects of pressure and laser thermal energy. This study describes a new device for coronary angioplasty using radiofrequency thermal energy. METHODS: Thirty-two patients with failed conventional coronary angioplasty or complex lesions were treated with radiofrequency thermal balloon coronary angioplasty. Radiofrequency energy was delivered up to 11 times in exposures ranging from 30 to 60 s in duration. This combined effect allowed the vascular wall to be heated to temperatures ranging from 60 to 70 degrees C. Follow-up coronary angiography was performed, on average, 6 months after the procedure. RESULTS: Successful radiofrequency coronary angioplasty was achieved in 28 (82%) of 34 lesions. There was one abrupt coronary artery occlusion (3%) and no death, perforation or dissection. Angiographic restenosis occurred in 14 (56%) of 25 lesions. CONCLUSIONS: In patients with failed coronary angioplasty and difficult complex lesions, radiofrequency coronary angioplasty could potentially improve angioplasty success rates and may have important implications for bailout cases with abrupt occlusion. However, restenosis remains a significant problem.     

Evaluating the potential cost-effectiveness of stenting as a treatment for symptomatic single-vessel coronary disease. Use of a decision-analytic model

BACKGROUND: Coronary stenting appears to provide more predictable immediate results and lower rates of restenosis than conventional balloon angioplasty for selected lesion types, but its hospital costs are significantly higher. This study was designed to evaluate the potential cost-effectiveness of Palmaz-Schatz coronary stenting relative to conventional balloon angioplasty for the treatment of patients with symptomatic, single-vessel coronary disease. METHODS AND RESULTS: We developed a decision-analytic model to predict quality-adjusted life expectancy and lifetime treatment costs for patients with symptomatic, single-vessel coronary disease treated by either Palmaz-Schatz stenting (PSS) or conventional angioplasty (PTCA). Estimates of the probabilities of overall procedural success (PTCA, 97%; PSS, 98%), abrupt closure requiring emergency bypass surgery (PTCA, 1.0%; PSS, 0.6%), and angiographic restenosis (PTCA, 37%; PSS, 20%) were derived from review of the literature published as of September 1993. Procedural costs were based on the true economic (ie, variable) costs of each procedure at Boston's Beth Israel Hospital. On the basis of these data, coronary stenting was estimated to result in a higher quality-adjusted life expectancy than conventional angioplasty but to incur additional costs as well. Compared with conventional angioplasty, stenting had an estimated incremental cost-effectiveness ratio of $23,600 per quality-adjusted life year gained. Although the cost-effectiveness ratio for stenting changed with variations in assumptions about the relative costs and restenosis rates, it remained less than $40,000 per quality-adjusted year of life gained--and thus was similar to many other accepted medical treatments--unless the stent angiographic restenosis rate was > 23%, the angioplasty restenosis rate was < 34%, or the cost of stenting (including vascular complications) exceeded that of conventional angioplasty by more than $3000. The alternative strategy of secondary stenting (initial angioplasty followed by stenting only for symptomatic restenosis) was estimated to be both less effective and less cost-effective than primary stenting over a wide range of plausible assumptions and thus does not appear to be cost-effective when primary stenting is also an option. CONCLUSIONS: Decision-analytic modeling can be used to evaluate the potential cost-effectiveness of new coronary interventions. Our analysis suggests that despite its higher cost, elective coronary stenting may be a reasonably cost-effective treatment for selected patients with single-vessel coronary disease. Primary stenting is unlikely to be cost-effective for lesions with a low probability of restenosis (eg, < 30%) or for patients for whom the cost of stenting is expected to be much higher than usual (eg, because of a high risk of vascular complications). Given the sensitivity of the cost-effectiveness ratios to even modest variations in the relative restenosis rates and cost estimates, future studies will be necessary to determine more precisely the cost-effectiveness of coronary stenting for specific patient and lesion subsets.     

Coronary-artery stenting compared with balloon angioplasty for restenosis after initial balloon angioplasty. Restenosis Stent Study Group

BACKGROUND: Intracoronary stenting reduces the rate of restenosis after angioplasty in patients with new coronary lesions. We conducted a prospective, randomized, multicenter study to determine whether intracoronary stenting, as compared with standard balloon angioplasty, reduces the recurrence of luminal narrowing in restenotic lesions. METHODS: A total of 383 patients who had undergone at least one balloon angioplasty and who had clinical and angiographic evidence of restenosis after the procedure were randomly assigned to undergo standard balloon angioplasty (192 patients) or intracoronary stenting with a Palmaz-Schatz stent (191 patients). The primary end point was angiographic evidence of restenosis (defined as stenosis of more than 50 percent of the luminal diameter) at six months. The secondary end points were death, Q-wave myocardial infarction, bypass surgery, and revascularization of the target vessel. RESULTS: The rate of restenosis was significantly higher in the angioplasty group than in the stent group (32 percent as compared with 18 percent, P= 0.03). Revascularization of the target vessel at six months was required in 27 percent of the angioplasty group but in only 10 percent of the stent group (P=0.001). This difference resulted from a smaller mean (+/-SD) minimal luminal diameter in the angioplasty group (1.85+/-0.56 mm) than in the stent group (2.04+/-0.66 mm), with a mean difference of 0.19 mm (P=0.01) at follow-up. Subacute thrombosis occurred in 0.6 percent of the angioplasty group and in 3.9 percent of the stent group. The rate of event-free survival at 250 days was 72 percent in the angioplasty group and 84 percent in the stent group (P=0.04). CONCLUSIONS: Elective coronary stenting was effective in the treatment of restenosis after balloon angioplasty. Stenting resulted in a lower rate of recurrent stenosis despite a higher incidence of subacute thrombosis.     

A clinical trial comparing primary stenting of the infarct-related artery with optimal primary angioplasty for acute myocardial infarction: results from the Florence Randomized Elective Stenting in Acute Coronary Occlusions (FRESCO) trial

OBJECTIVES: This study sought to compare stenting of the primary infarct-related artery (IRA) with optimal primary percutaneous transluminal coronary angioplasty (PTCA) with respect to clinical and angiographic outcomes of patients with an acute myocardial infarction. BACKGROUND: Early and late restenosis or reocclusion of the IRA after successful primary PTCA significantly contributes to increased patient morbidity and mortality. Coronary stenting results in a lower rate of angiographic and clinical restenosis than standard PTCA in patients with angina and with previously untreated, noncomplex lesions. METHODS: After successful primary PTCA, 150 patients were randomly assigned to elective stenting or no further intervention. The primary end point of the trial was a composite end point, defined as death, reinfarction or repeat target vessel revascularization as a consequence of recurrent ischemia within 6 months of randomization. The secondary end point was angiographic evidence of restenosis or reocclusion at 6 months after randomization. RESULTS: Stenting of the IRA was successful in all patients randomized to stent treatment. At 6 months, the incidence of the primary end point was 9% in the stent group and 28% in the PTCA group (p=0.003); the incidence of restenosis or reocclusion was 17% in the stent group and 43% in the PTCA group (p=0.001). CONCLUSIONS: Primary stenting of the IRA, compared with optimal primary angioplasty, results in a lower rate of major adverse events related to recurrent ischemia and a lower rate of angiographically detected restenosis or reocclusion of the IRA.     

Coronary restenosis after optimal (stent-like) initial angiographic results obtained by traditional balloon angioplasty

BACKGROUND AND OBJECTIVE: Elective native coronary artery stenting has shown its efficacy in lowering restenosis rates (RR) usually occurring after balloon angioplasty (PTCA). However ability of conventional PTCA to consistently provide low RR, through the achievement of large acute stent-like angiographic results, has not been investigated. This study was conducted to: (1) assess ability of optimal initial dilatation (OID), defined by residual lumen narrowing < or = 20%, significantly reduce current high RR following traditional PTCA; (2) evaluate the efficacy of OID obtainable by conventional PTCA in influencing adverse effects of single variables predisposing to restenosis. METHODS: Of consecutive 601 patients who underwent PTCA, 569 (94.6%), 483 men and 86 women, aged 38-76 years, had a successful procedure on 645/678 lesions (95.1%). After a plaque fracture was obtained by the first inflation, step-increases in pressure of 1 atm and 60 second-inflation-times were applied, until a large lumen (the nearest to normal) and smooth contours were seen, or any wall damage detected by using step-by-step angiographic tests. Acute optimal results (group A) were 450 (69.7%) and sub-optimal results (group B) were 203 (30.3%). After a mean time of 9 +/- 1.8 months, 543 patients (95.4%) had angiographic restudy on 611 (94.7%) successfully treated lesions. RESULTS: Restenosis (> 50% stenosis at restudy) occurred in 27.1% of patients and in 24.5% of lesions. RR was 18.8% in group A and 37.8% in group B (p < 0.0001). Significant lower RR were observed in group A in comparison with group B, for single variables examined, except for length > 10 mm. By multivariate analysis of all treated lesions, sub-optimal initial dilatation, unstable angina, lesion length > 10 mm and eccentricity emerged as major determinants of restenosis. Following OID only length > 10 mm was highly predictive of this event and, in the absence of this adverse variable, RR was only 13.6%. CONCLUSION: Counterbalancing adverse effects of many variables predisposing to restenosis, OID obtained by traditional PTCA seem to significantly reduce the risk of recurrence, particularly in lesions no longer than 10 mm.     

The relation between multiple sleep latency test findings and the frequency of apneic events in REM and non-REM sleep

OBJECTIVES: The purpose of this prospective study was to evaluate the immediate results and the 6-month angiographic recurrent restenosis rate after balloon angioplasty for in-stent restenosis. BACKGROUND: Despite excellent immediate and mid-term results, 20% to 30% of patients with coronary stent implantation will present an angiographic restenosis and may require additional treatment. The optimal treatment for in-stent restenosis is still unclear. METHODS: Quantitative coronary angiography (QCA) analyses were performed before and after stent implantation, before and after balloon angioplasty for in-stent restenosis and on a 6-month systematic coronary angiogram to assess the recurrent angiographic restenosis rate. RESULTS: Balloon angioplasty was performed in 52 patients presenting in-stent restenosis. In-stent restenosis was either diffuse (> or =10 mm) inside the stent (71%) or focal (29%). Mean stent length was 16+/-7 mm. Balloon diameter of 2.98+/-0.37 mm and maximal inflation pressure of 10+/-3 atm were used for balloon angioplasty. Angiographic success rate was 100% without any complication. Acute gain was lower after balloon angioplasty for in-stent restenosis than after stent implantation: 1.19+/-0.60 mm vs. 1.75+/-0.68 mm (p=0.0002). At 6-month follow-up, 60% of patients were asymptomatic and no patient died. Eighteen patients (35%) had repeat target vessel revascularization. Angiographic restenosis rate was 54%. Recurrent restenosis rate was higher when in-stent restenosis was diffuse: 63% vs. 31% when focal, p=0.046. CONCLUSIONS: Although balloon angioplasty for in-stent restenosis can be safely and successfully performed, it leads to less immediate stenosis improvement than at time of stent implantation and carries a high recurrent angiographic restenosis rate at 6 months, in particular in diffuse in-stent restenosis lesions.     

Immobilization of domestic goats (Capra hircus) using orally administered carfentanil citrate and detomidine hydrochloride

A total of 147 stents were implanted (in overlapping manner in 76% of vessels) in a single coronary artery in 59 patients (60 vessels, 97 lesions, 2.45 stents/vessel) over a period of 18 mo using high pressure stent deployment without ultrasound guidance. The indications for stenting were suboptimal percutaneous transluminal coronary angioplasty (PTCA) result (45%), primary prevention of restenosis (44%), acute closure (10%), and restenosis after plain balloon angioplasty (1%). One patient required emergency coronary artery bypass grafting (CABG) (extensive dissection), and one required early intervention with plain balloon angioplasty and intracoronary urokinase for stent thrombosis. There were no deaths. Thirteen patients had recurrence of angina within 6 mo and angiograms were performed in all. These showed intrastent restenosis in nine (all had successful repeat plain balloon angioplasty), development of new disease in other vessels along with restenosis close to the stent in the target vessel in one (underwent elective CABG) and normal angiograms with widely patent stents in three. Forty-five patients (77%) remained free of recurrent angina and 25 of these had follow-up angiograms (56%) at a mean of 172 days, two showing restenosis. Thus, the restenosis rate per patient in the symptomatic group (angiographic follow-up in 100%) was 77% and in the asymptomatic group (angiographic follow-up in 56%) was 8%. The restenosis rate in the subgroup with bailout stenting (n = 6) was 20% (angiographic follow-up in 83%). The overall restenosis rate per patient was 32% (overall angiographic follow-up in 66%). During the 6-mo follow-up period, one patient underwent elective CABG (1.7%), one sustained a non-Q myocardial infarction (1.7%), nine had repeat PTCA to the target vessel (15.5%), and there were no deaths. The event-free survival rate was 77%. Multiple stent implantation aided by high pressure stent deployment without ultrasound guidance and with adjunctive optimal antiplatelet therapy without oral anticoagulation seems to be a useful and effective revascularisation strategy to deal with long lesions and acute dissections with a high procedural success rate. The restenosis rate is acceptable and is not appreciably high as reported in previous studies from the "warfarin era."     

Mechanical debulking versus balloon angioplasty for the treatment of true bifurcation lesions

OBJECTIVES: The purpose of this study was to compare the immediate angiographic and long-term results of debulking versus balloon angioplasty for treatment of true bifurcation lesions. BACKGROUND: Previous studies have shown true bifurcation lesions to be a high risk morphological subset for percutaneous transluminal coronary angioplasty (PTCA). Although atherectomy devices have been used to treat bifurcation lesions, no studies have compared the outcomes of these alternative treatment modalities. METHODS: Between January 1992 and May 1997, we treated 70 consecutive patients with true bifurcation lesions (defined as a greater than 50% stenosis in both the parent vessel and contiguous side branch) with conventional PTCA (n = 30) or debulking (with rotational or directional atherectomy) plus adjunctive PTCA (n = 40). Paired angiograms were analyzed by quantitative angiography, and clinical follow-up was obtained in all patients. RESULTS: Acute procedural success was 73% in the PTCA group and 97% in the debulking group (p = 0.01). Major in-hospital complications occurred in two patients in the PTCA group and one in the debulking group. Treatment with atherectomy plus PTCA resulted in lower postprocedure residual stenoses than PTCA alone (16+/-15% vs. 33+/-17% in the parent vessel, and 6+/-15% vs. 39+/-22% in the side branch; p < 0.001 for both comparisons). At 1 year follow-up, the incidence of target vessel revascularization (TVR) was 53% in the PTCA group as compared with 28% in the debulking group (p = 0.05). Independent predictors of the need for repeat TVR were side branch diameter >2.3 mm, longer lesion lengths, and treatment with PTCA alone. CONCLUSIONS: For the treatment of true bifurcation lesions, atherectomy with adjunctive PTCA is safe, improves acute angiographic results, and decreases target vessel revascularization compared to PTCA alone. The benefits of debulking for bifurcation lesions were especially seen in lesions involving large side branches.     

Optimal coronary balloon angioplasty with provisional stenting versus primary stent (OCBAS): immediate and long-term follow-up results

OBJECTIVE: This study sought to compare two strategies of revascularization in patients obtaining a good immediate angiographic result after percutaneous transluminal coronary angioplasty (PTCA): elective stenting versus optimal PTCA. A good immediate angiographic result with provisional stenting was considered to occur only if early loss in minimal luminal diameter (MLD) was documented at 30 min post-PTCA angiography. BACKGROUND: Coronary stenting reduces restenosis in lesions exhibiting early deterioration (>0.3 mm) in MLD within the first 24 hours (early loss) after successful PTCA. Lesions with no early loss after PTCA have a low restenosis rate. METHODS: To compare angiographic restenosis and target vessel revascularization (TVR) of lesions treated with coronary stenting versus those treated with optimal PTCA, 116 patients were randomized to stent (n=57) or to optimal PTCA (n=59). After randomization in the PTCA group, 13.5% of the patients crossed over to stent due to early loss (provisional stenting). RESULTS: Baseline demographic and angiographic characteristics were similar in both groups of patients. At 7.6 months, 96.6% of the entire population had a follow-up angiographic study: 98.2% in the stent and 94.9% in the PTCA group. Immediate and follow-up angiographic data showed that acute gain was significantly higher in the stent than in the PTCA group (1.95 vs. 1.5 mm; p < 0.03). However, late loss was significantly higher in the stent than the PTCA group (0.63+/-0.59 vs. 0.26+/-0.44, respectively; p=0.01). Hence, net gain with both techniques was similar (1.32< or =0.3 vs. 1.24+/-0.29 mm for the stent and the PTCA groups, respectively; p=NS). Angiographic restenosis rate at follow-up (19.2% in stent vs. 16.4% in PTCA; p=NS) and TVR (17.5% in stent vs. 13.5% in PTCA; p=NS) were similar. Furthermore, event-free survival was 80.8% in the stent versus 83.1% in the PTCA group (p=NS). Overall costs (hospital and follow-up) were US $591,740 in the stent versus US $398,480 in the PTCA group (p < 0.02). CONCLUSIONS: The strategy of PTCA with delay angiogram and provisional stent if early loss occurs had similar restenosis rate and TVR, but lower cost than primary stenting after PTCA.     

Anti-atherogenicity in women does not prevent restenosis after balloon angioplasty

To test the hypothesis that anti-atherogenicity in women exerts beneficial effects to prevent restenosis formation after coronary angioplasty, we studied 493 men (988 lesions) and 81 women (159 lesions), aged 40-60 years, who had undergone successful balloon angioplasty and had follow-up angiography, 4.9 +/- 4.1 months later. We compared the extent of restenosis between men and women, and between pre- and post-menopausal women, which was assessed by a categorical definition of restenosis (more than 50% diameter stenosis at follow-up) and by percent diameter measured immediately after angioplasty and at follow-up. Hypertension was more frequent in women and a significantly lower percentage of women smoked. In women, the levels of total cholesterol and low-density lipoprotein cholesterol were higher. The location of dilated lesions, frequency of angioplasty for lesions with chronic total occlusion, and frequency of emergency angioplasty in patients with unstable angina or acute myocardial infarction were similar in men and women. Restenosis formation, estimated by the categorical definition or percent diameter, did not differ between men and women, or between pre- and post-menopausal women. Menopausal status or sex was not an independent predictor of restenosis by multivariate analysis. Thus, the benefit of anti-atherogenicity in women does not play an important role in preventing restenosis after coronary angioplasty.     

Neuroprotection from focal ischemia by 4-phenyl-1-(4-phenylbutyl) piperidine (PPBP) is dependent on treatment duration in rats

OBJECTIVES: We sought to determine whether treatment with high dose verapamil prevents restenosis in patients at high risk for reoccurrence after successful percutaneous transluminal coronary angioplasty (PTCA). BACKGROUND: Restenosis is the major limitation of PTCA. Calcium antagonists have demonstrated some potential as inhibitors of this process. METHODS: A total of 98 patients with peripheral occlusive arterial disease (POAD), stable angina pectoris, mild hypertension and at least one additional risk factor increasing the likelihood of restenosis after angioplasty were selected for this placebo-controlled, double-blind, randomized trial. Verapamil (240 mg twice daily) or placebo was taken for 6 months. Efficacy variables assessed before and after angioplasty and at 6 weeks and 6 months after PTCA included thickness of the intima/media complex degree of stenosis, interventricular septal thickness, crurobrachial pressure ratios of dorsalis pedis and posterior tibial arteries, distance to claudication and total vessel diameter. RESULTS: No significant intergroup differences emerged before or immediately after PTCA. Six weeks after angioplasty, a significant thickening of the intima/media complex in the treated vascular segment of 14.3% occurred in the placebo group versus 0% among verapamil patients (p < 0.01). At 6 months, the intima/media thickness was 35.7% greater in the placebo group but had decreased by 14.3% in the verapamil group (p < 0.001). At 6 months, a marked reduction in septal thickness was observed in the verapamil group versus that in the placebo group (p < 0.001). The rate of restenosis was also significantly lower in the verapamil group (p < 0.001). Few minor side effects were reported. CONCLUSIONS: In patients with POAD at increased risk for restenosis, the administration of high dose verapamil prevented recurrent stenosis for 6 months after successful peripheral angioplasty and was well tolerated.     

Immediate and long-term effect of balloon angioplasty or stent implantation on the absolute and relative coronary blood flow velocity reserve

BACKGROUND: There is controversy regarding the immediate and long-term effects of PTCA on the coronary flow reserve. METHODS AND RESULTS: A total of 54 patients with 1-vessel disease and normal left ventricular function were studied after balloon angioplasty (n=34) or stent implantation (n=20). Distal coronary blood flow velocity reserve (CFR) was defined as the ratio of adenosine-induced hyperemic versus baseline blood flow velocity with a 0.014-in Doppler guidewire. The relative CFR was defined as the ratio of the distal CFR and the reference CFR measured in the normal adjacent coronary artery. Hemodynamic and angiographic measurements were performed before and directly after balloon angioplasty or stent implantation and at 6-month follow-up. CFR after PTCA 相似文献   

Acute angiographic and clinical results of long balloon percutaneous transluminal coronary angioplasty and adjuvant stenting for long narrowings

Historically, long coronary artery stenoses undergoing percutaneous transluminal coronary angioplasty (PTCA) are reported to have reduced procedural and clinical success in comparison with shorter lesions. The efficacy of long balloons (30 or 40 mm) in long lesions was evaluated. Eighty-two patients had 84 PTCA procedures with a primary long balloon. In all, 86 lesions were available for analysis. Data were collected prospectively on standard PTCA procedure forms. Coronary angiograms were reviewed and measured with digital calipers. Hospital charts were examined for complications. PTCA was performed in the left anterior descending artery in 44 cases (51%), the right coronary artery in 29 (34%) and the circumflex artery in 13 (15%). With the use of a modified classification system, 47 lesions (55%) were class C, 24 (28%) were class B2 and 15 (17%) were class B1. Mean lesion length was 22 +/- 11 mm (range 10 to 72), and 38 lesions (44%) were > or = 20 mm. Twelve patients received an intracoronary stent. The long balloon alone produced angiographic success (< 50% residual stenosis) in 77 lesions (90%). Angiographic success was achieved ultimately in all stenoses, using a stent in 7 patients and a short balloon in 2. There were 2 deaths (2%) and 1 Q-wave myocardial infarction (1%). One patient needed coronary artery bypass surgery. Clinical success without death, Q-wave infarction or bypass surgery was achieved in 83 of 86 procedures (97%). In conclusion, the use of long PTCA balloons with adjuvant stenting produced excellent results in these long stenoses. Lesion length was not a precursor of poor angiographic or clinical outcome.     

Effectiveness of an antioxidant in preventing restenosis after percutaneous transluminal coronary angioplasty: the Probucol Angioplasty Restenosis Trial

OBJECTIVES: The Probucol Angioplasty Restenosis Trial was a prospective, randomized, controlled study that investigated the effectiveness of probucol therapy in reducing the rate of restenosis after percutaneous transluminal coronary angioplasty (PTCA). BACKGROUND: Antioxidants have an inhibitory effect on smooth muscle cell growth in experiments in vitro and in vivo, which suggests a possible pharmacologic effect on restenosis after PTCA. METHODS: One hundred one patients were randomly assigned to receive 1,000 mg/day of probucol or control (no lipid-lowering) therapy 4 weeks before PTCA. After 4 weeks of premedication, both groups underwent PTCA. Probucol was continued until follow-up angiography 24 weeks after PTCA. Angiographic results were analyzed at a core laboratory by quantitative coronary angiography. RESULTS: Dilation was successful in 46 of 50 patients in the probucol group and 45 of 51 in the control group. At follow-up angiography 24 weeks after angioplasty, angiographic restenosis occurred in 9 (23%) of 40 patients in the probucol group and 22 (58%) of 38 in the control group (p = 0.001). Minimal lumen diameter was 1.49 +/- 0.75 mm (mean +/- SD) in the probucol group and 1.13 +/- 0.65 mm in the control group (p = 0.02). Percent diameter stenosis at follow-up angiography in the probucol group was significantly lower than that in the control group (43.9% vs. 56.4%, p = 0.009). The late loss was 0.37 +/- 0.69 mm in the probucol group and 0.60 +/- 0.62 mm in the control group (p = 0.13). The loss/gain ratio was 0.32 +/- 0.74 in the probucol group and 0.56 +/- 0.81 in the control group (p = 0.059). Net gain was greater in the probucol group than in the control group (0.77 +/- 0.70 vs. 0.48 +/- 0.59 mm, p = 0.053). CONCLUSIONS: Probucol administered beginning 4 weeks before PTCA appears to reduce restenosis rates.     

Selenite and selenium yeast as feed supplements to growing fattening pigs

BACKGROUND: Coronary stenosis involves lipid accumulation, fibrosis and cell proliferation. OBJECTIVE: To clarify the role of oxidized low-density lipoprotein (LDL) in coronary stenosis by examining atherectomized coronary lesions from patients with primary stenosis and restenosis after percutaneous transluminal coronary angioplasty (PTCA). METHODS: Atherectomized coronary tissue from 28 patients with primary stenosis and restenosis at 4.3 +/- 1.0 months after PTCA were examined using morphometrical and immunohistochemical techniques. RESULTS: Serum lipids in all of the patients were within the normal range and no differences were noted between the two groups. There were no differences in the mean cross-sectional areas of whole specimens obtained from each group, and sclerotic lesions with atheroma or calcification were found to a similar extent in both groups. However, the restenosis group had a significantly greater area (6-fold) of immature smooth-muscle-rich lesions than the primary stenosis group, although there was no difference in lipid-laden foam-cell containing lesions. In foam-cell-containing lesions, apolipoprotein B was accumulated extracellularly, while oxidized LDL was primarily deposited intracellularly in lipid-laden foam cells. However, no deposition of apolipoprotein B, oxidized LDL or lipids was noted in smooth-muscle-rich lesions. Proline hydroxylase, a key enzyme for collagen synthesis, was detected in most of the foam-cell-containing lesions, but not in smooth-muscle-rich lesions. CONCLUSIONS: Atherectomized lesions from patients with coronary stenosis contained smooth-muscle-rich lesions in restenosis and lipid-laden cellular lesions in both stenosis and restenosis, in which the deposition of oxidized LDL and increased collagen synthesis occur coincidentally. Therefore, the mechanism of atherogenesis may involve coronary stenosis regardless of the occurrence of restenosis after PTCA therapy.     

The use of relational databases in the transition from quality assurance to continuous quality improvement: a clinical practice model

BACKGROUND AND OBJECTIVE: The solid-state, mid-infrared holmium:YAG laser (2.1 microm wavelength) is a relatively new percutaneous device that has recently been evaluated in a multicenter study. Because of its unique wavelength and photoacoustic effects on atherosclerotic plaques, this laser may be useful in treatment of symptomatic patients with coronary artery disease. This study sought to evaluate the safety and efficacy of mid-infrared laser angioplasty in the treatment of coronary artery lesions. PATIENTS AND METHODS: Laser angioplasty was performed on 2,038 atherosclerotic lesions in 1,862 consecutive patients with a mean age of 61 +/- 11 years. Clinical indications included unstable angina (69%), stable angina (20%), acute infarction (6%), and positive exercise test (5%). Complex lesion morphology included eccentricity (62%), thrombus (30%), total occlusion (27%), long lesions (14%), and saphenous vein grafts (11%). RESULTS: This laser catheter alone successfully reduced stenosis (>20%) in 87% of lesions. With adjunct balloon angioplasty, 93% procedural success was achieved. The presence of thrombus within the target lesion was a predictor of procedural success (OR = 2.0 [95% confidence interval 2.0, 4.0], P = .04). Bifurcation lesions (OR = 0.5 [95% confidence interval 0.2, 1.0], P = .05) and severe tortuosity of the treated vessel (OR = 0.4 [95% confidence interval 0.2, 0.9], P = .02) were identified as significant predictors of decreased laser success. Calcium within the lesion was associated with reduced procedural success (OR = 0.57 [95% confidence interval 0.34, 0.97], P = .03), and calcified lesions required significantly more energy pulses than noncalcified lesions (119 +/- 91 pulses vs. 101 +/- 86 pulses, respectively, P = .0002). Complications included in-hospital bypass surgery 2.5%, Q-wave myocardial infarction 1.2%, and death 0.8%. Perforation occurred in 2.2% of patients; major dissection in 5.8% of patients, and spasm in 12% of patients. No predictor of major complications was identified. Six-month angiographic restenosis was documented in 54% of patients, and clinical restenosis occurred in 34% of patients. CONCLUSION: Mid-infrared laser has a safety profile similar to that of other debulking devices. This laser may be useful in select patients presenting with acute ischemic syndromes associated with intracoronary thrombus; however, like other coronary lasers, it is limited by the need for adjunctive balloon angioplasty and/or stenting to achieve adequate final luminal diameter. No beneficial effects on reducing 6-month restenosis rates were observed.     

Restenosis rates in diabetic patients: a comparison of coronary stenting and balloon angioplasty in native coronary vessels

BACKGROUND: Diabetes is a major risk factor for restenosis after coronary balloon angioplasty. Recent studies have shown that coronary stenting significantly reduces restenosis compared with balloon angioplasty alone. However, limited information is available on the effect of coronary stenting in diabetic patients. METHODS AND RESULTS: We designed this study to analyze the effect of diabetes on restenosis in patients treated with either balloon angioplasty or coronary stenting who were enrolled in a 6-month angiographic follow-up program. Three hundred consecutive patients, 19% of whom were diabetics, who underwent coronary stent implantation during a single-vessel procedure on native coronary vessels and who had 6-month angiographic follow-up constituted the study group (stent group). Three hundred consecutive patients who underwent 6-month angiographic follow-up after single-vessel conventional balloon angioplasty served as control patients (balloon group). Preprocedural, postprocedural, and follow-up angiograms were analyzed with quantitative angiography. In the balloon group, the restenosis rate was almost twofold higher in diabetic than in nondiabetic patients (63% versus 36%; P=.0002) owing to both a greater late loss (0.79+/-0.70 versus 0.41+/-0.61 mm, respectively; P<.0001) and a higher rate of late vessel occlusion (14% versus 3%, respectively; P<.001). In the stent group, restenosis rates were similar in diabetics and nondiabetics (25% versus 27%, respectively). Furthermore, in the stent group, late loss (0.77+/-0.65 versus 0.79+/-0.57 mm, respectively) and the rate of late vessel occlusion (2% versus 1%, respectively) did not differ significantly between diabetic and nondiabetic patients. CONCLUSIONS: Although diabetics have increased rates of restenosis and late vessel occlusion after simple balloon angioplasty, they have the same improved outcome with coronary stenting that has been documented in nondiabetic patients.     

Insulin-stimulated Akt kinase activity is reduced in skeletal muscle from NIDDM subjects

The serum lipoprotein(a) [Lp(a)] level is a known risk factor for arteriosclerotic coronary artery disease. However, its association with restenosis after percutaneous transluminal coronary angioplasty (PTCA) is controversial. We hypothesized that the Lp(a) level is a significant risk factor for restenosis after angioplasty through a pathophysiological mechanism leading to excess thrombin generation or inhibition of fibrinolysis. We designed a prospective study of the relation of Lp(a) to outcome after PTCA, in which we measured selected laboratory variables at entry and collected clinical, procedural, lesion-related, and outcome data pertaining to restenosis. Restenosis was defined as >50% stenosis of the target lesion by angiography or as ischemia in the target vessel distribution by radionuclide-perfusion scan. Before the patients underwent PTCA, blood was obtained by venipuncture for measurement of Lp(a), total cholesterol, thrombin-antithrombin (TAT) complex, alpha2-antiplasmin-plasmin (APP) complex, and plasminogen activator inhibitor-1 (PAI-1). Evaluable outcome data were obtained on 162 subjects, who form the basis of this report. Restenosis occurred in 61 subjects (38%). The Lp(a) level was not correlated significantly with TAT, APP, PAI-1, or the TAT-APP ratio. Levels of TAT, APP, and PAI-1 were not statistically different in the patients with versus those without restenosis. The median ratio of TAT to APP was 2-fold higher in the restenosis group, and this difference approached statistical significance (P=0.07). Univariate analysis was performed for the association of clinical, lesion-related, and procedural risk factors with restenosis. Lp(a) levels did not differ significantly in the restenosis versus no-restenosis group, whether assessed categorically (>25 mg/dL versus <25 mg/dL) or as a continuous variable by Mann-Whitney U test. The number of lesions dilated and the lack of family history of premature heart disease were significantly associated with restenosis (P=0.002 and P=0.008, respectively). A history of diabetes mellitus was of borderline significance (P=0.055). By multiple logistic regression analysis, the number of lesions dilated was the only variable significantly associated with restenosis (P=0.03). We conclude that the number of lesions dilated during PTCA is a significant risk factor for restenosis, whereas the serum Lp(a) level was not a significant risk factor for restenosis in our patient population. The TAT to APP ratio merits further study as a possible risk factor for restenosis.     

Short- and long-term clinical and quantitative angiographic results with the new, less shortening Wallstent for vessel reconstruction in chronic total occlusion: a quantitative angiographic study

OBJECTIVES: This study was designed to examine whether oversized implantation of the new, less shortening Wallstent provides a more favorable long-term clinical and angiographic outcome in chronic total occlusions than does conventional coronary balloon angioplasty. BACKGROUND: Restenosis and reocclusion remain major limitations of balloon angioplasty for chronic total occlusions. Enforced mechanical remodeling by implantation of the oversized Wallstent may prevent elastic recoil and improve accommodation of intimal hyperplasia. METHODS: Lumen dimension was measured by a computer-based quantitative coronary angiography system (CAAS II). These measurements (before and after intervention and at 6-month follow-up) were compared between the groups with Wallstent implantation (20 lesions, 20 patients) and conventional balloon angioplasty (266 lesions, 249 patients) for treatment of chronic total occlusion. Acute gain (minimal lumen diameter after intervention minus that before intervention), late loss (minimal lumen diameter after intervention minus that at follow-up) and net gain (acute gain minus late loss) were examined. RESULTS: Wallstent deployment was successful in all patients. High pressure intra-Wallstent balloon inflation (mean +/- SD 14 +/- 3 atm) was performed in all lesions. Although vessel size did not differ between the Wallstent and balloon angioplasty groups, acute gain was significantly greater in the Wallstent group (2.96 +/- 0.55 vs. 1.61 +/- 0.34 mm, p < 0.0001). Although late loss was also significantly larger in the Wallstent group (0.81 +/- 0.95 vs. 0.43 +/- 0.68 mm, p < 0.05), net gain was still significantly greater in this group (2.27 +/- 1.00 vs. 1.18 +/- 0.69 mm, p < 0.0001). Angiographic restenosis (> or = 50% diameter stenosis) occurred at 6 months in 29% of lesions in the Wallstent group and in 45% of those in the balloon angioplasty group (p = 0.5150). CONCLUSIONS: Implantation of the oversized Wallstent, with full coverage of the lesion length, ensures resetting of the vessel size to its original caliber before disease and allows greater accommodation of intimal hyperplasia and chronic vessel recoil. Wallstent implantation provides a more favorable short- and long-term clinical and angiographic outcome than does conventional balloon angioplasty for chronic total occlusions.