Myocardial first-pass perfusion magnetic resonance imaging: a multicenter dose-ranging study.

BACKGROUND: MRI can identify patients with obstructive coronary artery disease by imaging the left ventricular myocardium during a first-pass contrast bolus in the presence and absence of pharmacologically induced myocardial hyperemia. The purpose of this multicenter dose-ranging study was to determine the minimally efficacious dose of gadopentetate dimeglumine injection (Magnevist Injection; Berlex Laboratories) for detecting obstructive coronary artery disease. METHOD AND RESULTS: A total of 99 patients scheduled for coronary artery catheterization as part of their clinical evaluation were enrolled in this study. Patients were randomized to 1 of 3 doses of gadopentate dimeglumine: 0.05, 0.10, or 0.15 mmol/kg. First-pass perfusion imaging was performed during hyperemia (induced by a 4-minute infusion of adenosine at a rate of 140 microg x kg(-1) x min(-1)) and then again in the absence of adenosine with otherwise identical imaging parameters and the same contrast dose. Perfusion defects were evaluated subjectively by 4 blinded reviewers. Receiver-operating curve analysis showed that the areas under the receiver-operating curve were 0.90, 0.72, and 0.83 for the low-, medium-, and high-contrast doses, respectively, compared with quantitative coronary angiography (diameter stenosis > or =70%). For the low-dose group, mean sensitivity was 93+/-0%, mean specificity was 75+/-7%, and mean accuracy was 85+/-3%. CONCLUSIONS: First-pass perfusion MRI is a safe and accurate test for identifying patients with obstructive coronary artery disease. A low dose of 0.05 mmol/kg gadopentetate dimeglumine is at least as efficacious as higher doses.

Clinical outcomes of compromised side branch (stent jail) after coronary stenting with the NIR stent.

Acute side-branch (SB) compromise or occlusion stent jail after native coronary stenting is a matter of concern. Attempts at maintaining SB patency can be a technical challenge. The purpose of this study was to determine the clinical impact of SB compromise or occlusion in patients undergoing stenting of parent vessel lesions. We evaluated in-hospital and long-term clinical outcomes (death, Q-wave myocardial infarction, and repeat revascularization rates at 6 months) in 318 consecutive patients undergoing NIR stent implantation across an SB. Based on independent angiographic analysis, 218 (68.6%) patients had no poststent SB compromise, 85 (26.7%) patients had narrowed SB (> 70% narrowing, without total occlusion), and 15 (4.7%) patients had an occluded SB after stent implantation. The baseline patient and lesion characteristics were similar between the groups. Procedural success was 100%. Patients with SB occlusion had a higher stents/lesion ratio (P < 0.006). Side-branch occlusion was associated with higher in-hospital ischemic complications (Q-wave myocardial infarction, 7%; non-Q-wave myocardial infarction, 20%; P < 0.05) compared to patients with SB compromise or normal SB. At 6-month follow-up, there was a trend for more myocardial infarctions in the group with SB occlusion during the index procedure (Q-wave myocardial infarction, 7% vs. 1% in the narrowed and 0% in normal SB; P = 0.09). However, late target lesion revascularization and mortality were similar in the three groups (P = 0.91). SB occlusion after parent vessel stenting is associated with more frequent in-hospital Q-wave and non-Q-wave myocardial infarctions. However, with the NIR stent, side-branch compromise or occlusion does not influence late (6 month) major adverse events, including death, myocardial infarction, or need for repeat revascularization.

Intravascular radiation therapy after balloon angioplasty of narrowed femoropopliteal arteries to prevent restenosis: results of the PARIS feasibility clinical trial.

PURPOSE: To conduct a feasibility study to assess the feasibility, safety, and outcome of endoluminal gamma radiation therapy after balloon angioplasty of superficial femoral artery (SFA) lesions. MATERIALS AND METHODS: Forty patients with claudication were enrolled in the study and underwent percutaneous transluminal angioplasty (PTA) of SFA lesions with a mean lesion length of 9.8 cm +/- 3.0 and a mean reference vessel diameter of 5.2 mm +/- 3.1. After successful PTA, a segmented centering balloon catheter was positioned to cover the PTA site. The patients were then transported to the radiation oncology suite and treated with a microSelectron HDR afterloader with use of an Ir-192 source with a prescribed dose of 14 Gy, 2 mm into the vessel wall. Ankle-brachial index (ABI) and Rutherford score were evaluated at 1, 6, and 12 months after the procedure and angiographic follow-up was conducted at 6 months. RESULTS: Radiation was delivered successfully to 35 of 40 patients. There were no procedural complications. Exercise and rest ABI were higher at 1 year (0.72 +/- 0.26 and 0.89 +/- 0.18, respectively) compared to baseline (0.51 +/- 0.25 and 0.67 +/- 0.17, respectively). Maximum walking time on a treadmill increased from 3.41 min +/- 2.41 to 4.43 min +/- 2.49 at 30 days and was 4.04 min +/- 2.8 at 12 months. The angiographic binary restenosis rate at 6 months was 17.2% and the clinical restenosis rate at 12 months was 13.3%. There were no angiographic or clinical adverse events related to the radiation therapy. CONCLUSIONS: Intraarterial radiation after PTA of SFA lesions with use of high-dose rate gamma radiation is feasible and safe. The angiographic and clinical improvements are sustainable at 1 year and represent a potent antirestenotic therapy for the treatment of narrowed peripheral arteries.

Differential impact on survival of electrocardiographic Q-wave versus enzymatic myocardial infarction after percutaneous intervention: a device-specific analysis of 7147 patients.

BACKGROUND: The relative prognostic importance of ECG myocardial infarction (MI) after intervention compared with varying degrees of enzymatic elevation has not been characterized, and the device-specific implications of periprocedural MI are also unknown. METHODS AND RESULTS: Serial creatine phosphokinase (CPK)-MB levels were determined after elective percutaneous intervention of 12 098 lesions in 7147 consecutive patients at a tertiary referral center. Procedural, in-hospital, and follow-up data were collected by independent research nurses, and clinical and ECG events were adjudicated by a separate committee. Stents were implanted in 50.6% of lesions, atheroablation was performed in 54.8%, and PTCA alone was performed in 9.8%. The peak periprocedural CPK-MB level was >3x the upper limit of normal (ULN) in 17.9% of patients, and Q-wave MI developed in 0.6%. By multivariate analysis, the periprocedural development of new Q waves was the most powerful independent determinant of death (2-year mortality rate, 38.3%; hazard ratio, 9.9; P<0.0001). Non-Q-wave MI with CPK-MB >8x ULN was also a strong predictor of death (2-year mortality rate, 16.3%; hazard ratio, 2.2; P<0.0001); survival was unaffected by lesser degrees of CPK-MB elevation. Though CPK-MB elevation was more common after atheroablation and stenting than PTCA, the rates of Q-wave MI and survival were device-independent. CONCLUSIONS: Myonecrosis after percutaneous intervention is common in a high-risk referral population dominated by atheroablation and stent use. Large periprocedural infarctions (signified by new Q waves and CPK-MB >8xULN) are powerful determinants of death, whereas lesser degrees of CPK-MB release and specific device use do not adversely affect survival.

Intravascular ultrasound-guided renal artery stenting.

PURPOSE: To evaluate the clinical outcomes of patients undergoing renal artery stenting with intravascular ultrasound (IVUS) guidance and compare measurements between IVUS and angiography. METHODS: One hundred thirty-one patients (71 women; mean age 71 +/- 8 years) underwent IVUS-guided Palmaz stent implantation in 153 stenotic renal arteries at a single center. The indications for stenting were uncontrolled hypertension (102, 77.9%), renal insufficiency (10, 7.6%), and both conditions (19, 14.5%). The majority of lesions were ostial (114, 74.5%); the remainder occupied the proximal renal artery (39, 25.5%). The mean lesion length and diameter stenosis were 6.5 +/- 3.0 mm and 74% +/- 10%, respectively, as measured by angiography. Data were recorded in a prespecified database; angiographic and IVUS images were analyzed at dedicated core laboratories and compared. RESULTS: Angiographic success was achieved in all patients, but IVUS indicated the need for additional intervention in 36 (23.5%) cases. There was strong correlation between the angiographic and IVUS measurements of lesion length (r = 0.60, p < 0.0001) and pre-/postprocedural minimal luminal diameter (r = 0.72 and 0.63, respectively; p < 0.0001). The mean contrast volume was 74 +/- 18 mL per case. In-hospital renal failure occurred in 8 (6.1%) patients; 2 (1.5%) required transient hemodialysis. At a mean 15-month follow-up, patients were treated with fewer antihypertensive medications (p = 0.05), and systolic and diastolic arterial blood pressures had decreased (p = 0.001); no significant change was noted in serum creatinine. CONCLUSIONS: IVUS-guided stenting facilitates safe renal artery revascularization. IVUS imaging may complement angiography in certain cases, which should be studied further in prospective studies with iodinated or noniodinated contrast agents.

Serial intravascular ultrasound analysis of edge recurrence after intracoronary gamma radiation treatment of native artery in-stent restenosis lesions.

In the Washington Radiation for In-Stent restenosis Trial (WRIST), patients were first treated with conventional techniques and then randomized to either gamma-irradiation ((192)Ir) or placebo (dummy seeds). In the (192)Ir group with native coronary in-stent restenosis, we identified 8 patients with edge recurrence and compared them with 21 patients with no recurrence. Serial (postirradiation and follow-up) intravascular ultrasound analysis was performed according to conventional methods. When compared with nonrecurring lesions, lesions with distal edge recurrence had (1) greater decrease in mean distal lumen cross-sectional area (-3.0 +/- 1.2 vs -0.7 +/- 1.0 mm(2), p = 0.0002), (2) no change in mean distal external elastic membrane cross-sectional area versus an increase in mean distal cross-sectional area of 1.0 +/- 0.9 mm(2) in nonrecurring lesions (p = 0.0047), and (3) a greater increase in mean distal plaque + media cross-sectional area (2.9 +/- 1.2 mm vs 1.7 +/- 0.6 mm(2), p = 0.0103). Within the stented segment, the nonrecurring lesions had no decrease in mean lumen and no increase in mean intimal hyperplasia cross-sectional area. Conversely, lesions with distal edge recurrence had a significant decrease in mean intrastent lumen cross-sectional area (-1.7 +/- 1.7 mm(2)) and a significant increase in mean intrastent intimal hyperplasia cross-sectional area (1.6 +/- 1.6 mm(2)). Lesions with distal edge recurrence also had a greater decrease in mean proximal lumen cross-sectional area (-1.7 +/- 1.3 vs -0.3 +/- 0.8 mm(2), p = 0.0213), with a trend toward a greater increase in mean proximal plaque + media cross-sectional area. Thus, edge recurrence after (192)Ir treatment of in-stent restenosis is the result of neointimal hyperplasia (part of generalized treatment failure) and the absence of radiation-induced positive remodeling.

Intracoronary radiation with gamma wire inhibits recurrent in-stent restenosis.

To study the safety and efficacy of intracoronary gamma radiation delivered via a new high-activity (192)Ir source wire for the treatment of in-stent restenosis. In-stent restenosis results from neointimal tissue proliferation especially in its diffused form and presents a therapeutic challenge. Gamma radiation has been shown to decrease neointima formation within stents in animal models and in initial clinical trials. A total of 26 patients with in-stent restenosis underwent successful intervention and was treated with open-label (192)Ir using a high-activity line source. The specific activity of the source wire was 372+/-51 mCi, and the dwell time was 10.8+/-1.9 min. Primary endpoints were freedom from death, myocardial infraction (MI), and repeat target lesion revascularization (TLR) at 6 months. Secondary endpoints included angiographic restenosis and intravascular ultrasound (IVUS) neointimal hyperplasia. Procedural success was high (96.2%), and in-hospital and 30-day complications were low with no deaths, MI, or requirement for repeat revascularization. At 6 months, event-free survival was 85%: one patient required repeat PTCA, one underwent bypass surgery, and two had an MI. Baseline lesion length measured 15.77 mm. Follow-up angiography was available in 21/25 (84%) patients. The binary restenosis rates were 19.0% (4/21) in-stent and 23.8% (5/21) in-lesion. Follow-up IVUS was available in 20/25 patients. There was no increase in intimal hyperplasia from postintervention to follow-up (3.11.8 vs. 3.41.8 mm(2); P=.32). Eight patients had a reduction of neointimal intimal tissue at follow-up. These results indicate that intracoronary gamma radiation with the Angiorad source wire is safe and effective in preventing in-stent restenosis.

Effectiveness of excimer laser coronary angioplasty in acute myocardial infarction or in unstable angina pectoris.

This study was conducted to evaluate the feasibility, safety, and acute results of percutaneous excimer laser coronary angioplasty (ELCA) in acute coronary syndromes. Fifty-nine patients were treated with ELCA (308 nm), including 33 patients with unstable angina pectoris (UAP) (35 vessels with 39 lesions) and 26 patients with acute myocardial infarction (AMI) (26 vessels with 29 lesions). In each patient the target lesion had a complex morphology. Overall, 71% of the patients had contraindications for pharmacologic thrombolytic agents or glycoprotein IIb/IIIa receptor antagonists. All patients received adjunct balloon dilation followed by stent implantation in 88% of patients with AMI versus 76% of patients with UAP (p = NS). Quantitative angiography was performed at an independent core laboratory; 86% laser success and 100% procedural success was achieved in the AMI group versus 87% laser success and 97% procedural success in the UAP group (p = NS). In the AMI group, the minimal luminal diameter increased from 0.77 +/- 0.56 to 1.44 +/- 0.47 mm after lasing to a final 2.65 +/- 0.47 mm versus 0.77 +/- 0.38 to 1.35 +/- 0.4 mm after lasing to 2.66 +/- 0.5 mm final in the UAP group. A prelaser percent stenosis of 76 +/- 17% for the AMI group versus 70 +/- 16% for the UAP group (p = NS) was decreased after lasing to 52 +/- 16% for the AMI group versus 51 +/- 14% for the UAP group (p = NS) and to a final stenosis of 15 +/- 17% for the AMI group versus 12 +/- 15% for the UAP group (p = NS). A 96% laser-induced reduction of thrombus burden area was achieved in the AMI group versus 97% in the UAP group (p = NS). Preprocedure Thrombolysis In Myocardial Infarction flow of 1.3 +/- 0.9 in the AMI group versus 2.3 +/- 1.2 for the UAP group (p = 0.01) increased to a final flow of 3.0 +/- 0 for the AMI group versus 3.0 +/- 0 for the UAP group (p = NS). There were no deaths, cerebrovascular accident, emergency bypass surgery, acute closure, major perforation or major dissection, distal embolization, or bleeding complications in either group. One patient with AMI had localized perforation (caused by guidewire) without sequelae and 1 patient with UAP had an abnormal increase in creatine kinase levels. All 59 patients survived the laser procedure, improved clinically, and were discharged. Thus, early experience in patients with acute coronary syndromes suggest that percutaneous ELCA is feasible and safe.

Carotid artery stenting in patients with high-risk anatomy for carotid endarterectomy.

PURPOSE: To report the results of carotid artery stenting (CAS) in patients considered to have high-risk anatomical characteristics for carotid endarterectomy. METHODS: CAS was performed in 39 carotid arteries of 37 consecutive patients (26 men; mean age 72 +/- 8 years, range 56-88) who met the criteria for high-risk surgical anatomy: previous ipsilateral carotid endarterectomy (20/39, 51.3%), common carotid bifurcation above the mandibular angle (5/39, 12.8%), contralateral carotid artery occlusion (15/39, 38.5%), or previous radiation therapy to the neck (1/39, 2.6%). Palmaz, Integra, or Wallstents were deployed via a percutaneous femoral artery access. Independent neurological evaluation was performed at specified time points, and a dedicated committee adjudicated all clinical events. RESULTS: Procedural success was 100%, with no major in-hospital complications. Neurological events were rare. Only 1 (2.6%) transient ischemic attack occurred prior to discharge; at 30 days, 1 (2.6%) additional minor stroke had been observed, giving a 2.6% cumulative 30-day "death plus any stroke" rate. Over a mean 11 +/- 6-month follow-up, 2 (5.4%) patients died of nonneurological causes, but there were no strokes. CONCLUSIONS: CAS is a viable endovascular revascularization technique that can be performed safely and effectively in patients with high-risk anatomy for carotid endarterectomy.

Localized intracoronary gamma-radiation therapy to inhibit the recurrence of restenosis after stenting.

BACKGROUND: Although the frequency of restenosis after coronary angioplasty is reduced by stenting, when restenosis develops within a stent, the risk of subsequent restenosis is greater than 50 percent. We report on a multicenter, double-blind, randomized trial of intracoronary radiation therapy for the treatment of in-stent restenosis. METHODS: Of 252 eligible patients in whom in-stent restenosis had developed, 131 were randomly assigned to receive an indwelling intracoronary ribbon containing a sealed source of iridium-192, and 121 were assigned to receive a similar-appearing nonradioactive ribbon (placebo). RESULTS: The primary end point, a composite of death, myocardial infarction, and the need for repeated revascularization of the target lesion during nine months of follow-up, occurred in 53 patients assigned to placebo (43.8 percent) and 37 patients assigned to iridium-192 (28.2 percent, P=0.02). However, the reduction in the incidence of major adverse cardiac events was determined solely by a diminished need for revascularization of the target lesion, not by reductions in the incidence of death or myocardial infarction. Late thrombosis occurred in 5.3 percent of the iridium-192 group, as compared with 0.8 percent of the placebo group (P=0.07), resulting in more late myocardial infarctions in the iridium-192 group (9.9 percent vs. 4.1 percent, P=0.09). Late thrombosis occurred in irradiated patients only after the discontinuation of oral antiplatelet therapy (with ticlopidine or clopidogrel) and only in patients who had received new stents at the time of radiation treatment. CONCLUSIONS: Intracoronary irradiation with iridium-192 resulted in lower rates of clinical and angiographic restenosis, although it was also associated with a higher rate of late thrombosis, resulting in an increased risk of myocardial infarction. If the problem of late thrombosis within the stent can be overcome, intracoronary irradiation with iridium-192 may become a useful approach to the treatment of in-stent restenosis.

Serial volumetric intravascular ultrasound analysis of the efficacy of beta irradiation in preventing recurrent in-stent restenosis.

We compared postintervention and follow-up intravascular ultrasound findings of 25 patients from the beta-Washington Radiation for InStent restenosis Trial (in which all patients received radiation) and 75 patients from the Washington Radiation for InStent restenosis Trial (in which patients were randomized to gamma irradiation). The decrease in lumen volume was similar for beta versus gamma and less in both gamma versus placebo and beta versus placebo; the increase in intimal hyperplasia volume was similar for beta versus gamma and greater in both beta versus placebo and gamma versus placebo.

Optimally deployed stents in the treatment of restenotic versus de novo lesions.

Results from earlier trials performed before the implementation of optimal stent deployment techniques suggest that stenting for restenotic lesions may be associated with a higher risk of restenosis when compared with de novo lesions. The aim of this study was to compare the short- and long-term outcome of optimal stent deployment in restenotic versus de novo lesions. In all, 1,865 consecutive patients with 2,707 de novo lesions and 489 patients with 633 restenotic lesions underwent intravascular ultrasound-guided optimal stent deployment. In-hospital outcome was similar for both groups, except for a higher incidence of non-Q-wave myocardial infarction in the de novo group (14.6% vs 8.6%, p = 0.001). At 12-month follow-up, there was no statistical significant difference in the incidence of death or myocardial infarction, but event-free survival was better in the de novo lesion group of patients (74.5% vs 63.7%, p = 0.001). There was a higher incidence of target lesion revascularization in the restenosis group (25.1% vs 13.0%, p = 0.001). By multivariate analysis, restenotic lesions, vein graft lesions, and diabetes mellitus were strong determinants of repeat revascularization, whereas larger preprocedural reference vessel minimal lumen diameter and larger final minimal lumen diameter were associated with a reduced chance of restenosis and increased event-free survival. This study shows that optimal stent deployment for restenotic and de novo lesions has favorable short- and long-term outcome. However, the incidence of target lesion revascularization was significantly greater in restenotic lesions. Saphenous vein graft lesions and diabetes mellitus were confirmed as other independent risk factors for clinical restenosis.

Acute and long-term results of treatment of diffuse in-stent restenosis in aortocoronary saphenous vein grafts.

Treatment of diffuse in-stent restenosis in saphenous vein grafts with excimer laser coronary angioplasty plus adjunct balloon angioplasty achieves an adequate acute result. However, this population has high long-term mortality and frequent need for repeat revascularization.

Intracoronary brachytherapy not associated with changes in major side branches.

Intravascular radiation (IR) is emerging as a potential solution for the prevention and treatment of restenosis. Subacute thrombosis late coronary occlusion of the target lesion after intracoronary brachytherapy has been described in two studies. None of these studies assessed in detail the evolution of side branches following IR. The purpose of this study was to determine the frequency of side-branch occlusion in patients undergoing IR. We evaluated the procedural and 6-month follow-up angiograms of 170 consecutive patients enrolled in the GAMMA-I and WRIST studies who presented a major side branch (diameter > 1.5 mm) at the treated lesion. Major side branches treated during the procedure and/or total occlusion of the main branch were excluded for analysis. Sixty-three patients (control = 30, irradiated = 33) were identified and side branches were classified in one of three categories: no significant stenosis, > 50% stenosis, and occluded. The baseline patient and lesion characteristics were similar among the classified groups. No difference was observed between the control and irradiated arteries after the procedure for side-branch occlusion (14% and 9%, P = NS). A significant decrease of restenosis was observed after IR compared to control (20% vs. 70%: P < 0.001). The patency rates and rates of side-branch occlusion were similar between the two groups. However, in the control group, 50% of the side-branch occlusions that occurred after the procedure were patent at 6-month follow-up. In contrast, in the irradiated group, the incidence of side-branch occlusion increased from 9% to 15% at 6-month follow-up in the irradiated group. Low doses of radiation applied to noninjured side branches are not associated with adverse effects. The absence of restoration patency followed by IR is most likely a consequence of a delayed healing process.

Late total occlusion after intracoronary brachytherapy for patients with in-stent restenosis.

OBJECTIVES: The study sought to determine the incidence and predictors of late total occlusion (LTO, >30 days) in-patients with in-stent restenosis who were treated with intracoronary radiation. BACKGROUND: Intracoronary radiation both with beta and gamma emitters has been shown to reduce recurrent in-stent restenosis. METHODS: We reviewed the records of 473 patients who presented with in-stent restenosis and who were enrolled in various radiation protocols, whether randomized to placebo versus radiation or entered into registries. There were 165 placebo and 308 radiated patients, including both gamma and beta emitters. Maximum dose to the vessel wall was 30 to 55 Gy. Following radiation, all patients received antiplatelet therapy with aspirin and either ticlopidine or clopidogrel for one month. All patients completed at least six months of angiographic follow-up. RESULTS: The LTO was documented in 28 patients (9.1%) from the irradiated group versus 2 placebo patients (1.2%), p < 0.0001. The LTO rates were similar across studies and emitters. In the irradiated group, LTO presented as acute myocardial infarction in 12 patients (43%), unstable angina in 14 (50%), and asymptotic in 2 (7%). Mean time to LTO was 5.4 +/- 3.2 months in the irradiated group versus 4.5 +/- 2.1 in placebo patients (p = NS). The overall rate of restenting for the entire study group at the time of radiation was 48.6%. Importantly, new stents were placed in 82% of the irradiated and in 100% of the placebo patients who presented with LTO. Multivariate analysis determined that new stenting was the main predictor of LTO. CONCLUSIONS: Intracoronary radiation for patients with in-stent restenosis is associated with a high rate of LTO. Restenting may contribute late thrombosis. Prolonged antiplatelet therapy (up to six months) should be considered for these patients.

Mechanism of lumen enlargement during intracoronary stent implantation: an intravascular ultrasound study.

BACKGROUND: Intravascular ultrasound analysis has assessed mechanisms of lumen enlargement after nonstent interventions, but not after stenting. METHODS AND RESULTS: Preintervention and postintervention intravascular ultrasound was used to study 25 de novo native coronary lesions treated with single MultiLink stents without preatheroablation. External elastic membrane, lumen, and plaque and media (P&M) areas were measured every 1 mm to include the lesion and reference segments that were 5 mm proximal and distal to it. Lesion mean lumen area increased from 4.0+/-1.0 mm(2) before the intervention to 8.8+/-2.0 mm(2) after the intervention (P<0.0001) as a result of an increase in mean external elastic membrane area (14. 2+/-2.7 to 16.1+/-3.0 mm(2), P<0.0001) and a decrease in mean P&M area (10.2+/-2.2 to 7.2+/-1.8 mm(2), P<0.0001). The decrease in lesion P&M was accompanied by an increase in both proximal reference mean P&M (7.0+/-1.9 to 8.4+/-2.0 mm(2), P<0.0001) and distal reference mean P&M (5.8+/-2.1 to 7.2+/-2.1 mm(2), P<0.0001). Volumetric analysis showed an axial redistribution of plaque away from the center of the lesion toward the reference segments to increase the plaque burden in both the proximal and distal reference segments. Total (lesion plus reference) mean P&M decreased from 8. 6+/-2.1 to 7.5+/-1.8 mm(2) (P<0.0001). CONCLUSIONS: The mechanisms of lumen enlargement after stenting involved (1) significant axial redistribution of plaque from the lesion into the reference segments, (2) vessel expansion, and (3) either plaque embolization or compression.

Current perspectives on interventional treatment strategies in diabetic patients with coronary artery disease.

Diabetes mellitus has a negative impact on mortality and morbidity following catheter-based coronary procedures as well as coronary artery bypass surgery. Increased restenosis remains the main limitation of catheter-based coronary intervention among diabetes mellitus in addition to accelerated atherosclerosis lesion progression in other untreated coronary sites. Determinants such as excess restenosis, high atherosclerosis burden, lesion complexity, small target vessel size, and accelerated coronary atherosclerosis in remote sites may favor the surgical strategy in most cases of diabetic multivessel disease. The importance of periprocedural adjunctive pharmacotherapy, specifically with the use of antiplatelet and long-term antilipidemic treatment, was shown to improve outcomes in diabetics undergoing percutaneous coronary interventions. The purpose of the review is to examine potential mechanisms causing more restenosis in diabetics, the clinical outcomes of patients with diabetes after coronary interventions including stenting, the treatment alternatives of diabetic patients with diffuse coronary artery disease, including coronary bypass surgery, and current understanding of the benefit of adjunctive pharmacology on clinical outcomes after coronary interventions among diabetics.

Comparison of debulking followed by stenting versus stenting alone for saphenous vein graft aortoostial lesions: immediate and one-year clinical outcomes.

OBJECTIVES: We compared in-hospital and one-year clinical outcomes in patients undergoing debulking followed by stent implantation versus stenting alone for saphenous vein graft (SVG) aortoostial lesions. BACKGROUND: Stent implantation in SVG aortoostial lesions may improve procedural and late clinical outcomes. However, the impact of debulking before stenting in this complex lesion subset is unknown. METHODS: We studied 320 consecutive patients (340 SVG aortoostial lesions) treated with Palmaz-Schatz stents. Debulking with excimer laser or atherectomy was performed in 133 patients (139 lesions) before stenting (group I), while 187 patients (201 lesions) underwent stent implantation without debulking (group II). Procedural success and late clinical outcomes were compared between the groups. RESULTS: Overall procedural success (97.6%) was similar between the groups. Procedural complications were also similar (2.2% for group I and 2.6% for group II). At one-year follow-up, target lesion revascularization (TLR) was 19.4% for group I and 18.2% for group II (p = 0.47). There was no difference in cumulative death or Q wave myocardial infarction between the groups. Overall cardiac event-free survival was similar (69% for group I and 68% for group II). By Cox regression analysis, the independent predictors of late cardiac events were final lumen cross-sectional area (CSA) by intravascular ultrasound (IVUS) (p = 0.001) and restenotic lesions (p = 0.01). Similarly, final IVUS lumen CSA (p = 0.0001) and restenotic lesions (p = 0.006) were found to predict TLR at one year. CONCLUSIONS: These results suggest that, in most patients with SVG aortoostial lesions, debulking before stent implantation may not be necessary.

Intracoronary gamma-radiation therapy after angioplasty inhibits recurrence in patients with in-stent restenosis.

BACKGROUND: Treatment of in-stent restenosis presents a critical limitation of intracoronary stent implantation. Ionizing radiation has been shown to decrease neointimal formation within stents in animal models and in initial clinical trials. We studied the effects of intracoronary gamma-radiation therapy versus placebo on the clinical and angiographic outcomes of patients with in-stent restenosis. METHODS AND RESULTS: One hundred thirty patients with in-stent restenosis underwent successful coronary intervention and were then blindly randomized to receive either intracoronary gamma-radiation with (192)Ir (15 Gy) or placebo. Four independent core laboratories blinded to the treatment protocol analyzed the angiographic and intravascular ultrasound end points of restenosis. Procedural success and in-hospital and 30-day complications were similar among the groups. At 6 months, patients assigned to radiation therapy required less target lesion revascularization and target vessel revascularization (9 [13.8%] and 17 [26.2%], respectively) compared with patients assigned to placebo (41 [63.1%, P=0.0001] and 44 [67.7%, P=0.0001], respectively). Binary angiographic restenosis was lower in the irradiated group (19% versus 58% for placebo, P=0.001). Freedom from major cardiac events was lower in the radiation group (29.2% versus 67.7% for placebo, P<0.001). CONCLUSIONS: Intracoronary gamma-radiation used as adjunct therapy for patients with in-stent restenosis significantly reduces both angiographic and clinical restenosis.

Intracoronary beta-radiation therapy inhibits recurrence of in-stent restenosis.

BACKGROUND: Intracoronary gamma-radiation therapy reduces recurrent in-stent restenosis (ISR). This study, BETA WRIST (Washington Radiation for In-Stent restenosis Trial) was designed to examine the efficacy and safety of the beta-emitter 90-yttrium for the prevention of recurrent ISR. METHODS AND RESULTS: A total of 50 consecutive patients with ISR in native coronaries underwent percutaneous transluminal coronary angioplasty, laser angioplasty, rotational atherectomy, and/or stent implantation. Afterward, a segmented balloon catheter was positioned and automatically loaded with a 90-yttrium, 0.014-inch source wire that was 29 mm in length to deliver a dose of 20.6 Gy at 1.0 mm from the balloon surface. In 17 patients, manual stepping of the radiation catheter was necessary for lesions >25 mm in length. The radiation was delivered successfully to all patients, with a mean dwell time of 3.0+/-0.4 minutes. Fractionation of the dose due to ischemia was required in 11 patients. At 6 months, the binary angiographic restenosis rate was 22%, the target lesion revascularization rate was 26%, and the target vessel revascularization rate was 34%; all rates were significantly lower than those of the placebo group of gamma-WRIST. CONCLUSIONS: beta-Radiation with a 90-yttrium source used as adjunct therapy for patients with ISR results in a lower-than-expected rate of angiographic and clinical restenosis.