[4th universal definition of myocardial infarction 2018 : What is new?] / 4. Allgemeine Definition des Myokardinfarkts 2018 : Was ist neu?

The 4th universal definition of myocardial infarction consensus document is a further development of the document from 2012. It highlights the discrimination between myocardial injury and infarction and in particular the periprocedural occurrence of increased troponin levels. The chapter on cardiac biomarkers deals with the problems of comparison of various troponin assays and the kinetics of troponin in acute myocardial infarction. The definition of the 5 types of myocardial infarction underwent only minor changes. In the chapter on ECG interpretation high-risk constellations are described. A total of six new chapters were added to the consensus document including the takotsubo syndrome and myocardial infarction with non-obstructive coronary arteries (MINOCA), which are briefly discussed.

[Carotid artery stenting technique]. / Technik der Karotis-PTA.

Over the past 25 years carotid artery stenting (CAS) has emerged as an alternative to carotid endarterectomy (CEA). Most of all younger patients and symptomatic patients with contralateral carotid artery occlusion particularly benefit from CAS. To achieve an optimal result with CAS, patient selection and even more important, knowledge and experience of the interventionist is crucial. The periprocedural complication rate of CAS in large experienced centers is lower (2-3%) than those in randomized trials. Several different devices are now available which allow the procedure to be tailored according to patient anatomy and lesion complexity. Complications like hyperperfusion syndrome and intracerebral bleeding, rupture of side branches of the external or internal carotid artery as well as problems caused by slow flow can be widely avoided by adequate experience.

Impact of late incomplete stent apposition after sirolimus-eluting stent implantation on 4-year clinical events: intravascular ultrasound analysis from the multicentre, randomised, RAVEL, E-SIRIUS and SIRIUS trials.

BACKGROUND: The impact of incomplete stent apposition (ISA) after drug-eluting stent implantation determined by intravascular ultrasound (IVUS) on late clinical events is not well defined. OBJECTIVE: To evaluate the clinical impact of ISA after sirolimus-eluting stent (SES) placement during a follow-up period of 4 years. DESIGN: Pooled analysis from the RAVEL, E-SIRIUS and SIRIUS trials, three randomised, multicentre studies comparing SES and bare-metal stents (BMS). METHODS: IVUS at angiographic follow-up was available in 325 patients (SES: n = 180, BMS: n = 145). IVUS images were reviewed for the presence of ISA defined as one or more unapposed stent struts. Clinical follow-up was available for a 4-year period in all patients. Frequency, predictors and clinical sequel of ISA at follow-up after SES and BMS implantation were determined. RESULTS: ISA at follow-up was more common after SES (n = 45 (25%)) than after BMS (n = 12 (8.3%), p<0.001). Canadian Cardiology Society class III or IV angina at stent implantation (odds ratio (OR) = 4.69, 95% CI 2.15 to 10.23, p<0.001) and absence of diabetes (OR = 3.42, 95% CI 1.05 to 11.1, p = 0.041) were predictors of ISA at follow-up after SES placement. Rate of myocardial infarction tended to be slightly higher for ISA than for non-ISA patients. When SES patients only were considered, major adverse cardiac event free survival at 4 years was identical for those with and without ISA at follow-up (11.1% vs 16.3%, p = 0.48). CONCLUSIONS: ISA at follow-up is more common after SES implantation than after BMS implantation. Considering the current very sensitive IVUS definition, ISA appears to be an IVUS finding without significant impact on the incidence of major adverse cardiac events even during long-term follow-up.

Multicenter evaluation of a self-expanding carotid stent system with distal protection in the treatment of carotid stenosis.

PURPOSE: Carotid artery stent placement may be limited by the embolization of atheromatous material. We evaluated the safety and feasibility of the Medtronic Self-Expanding Carotid Stent (Exponent) in combination with the Medtronic Interceptor Carotid Filter System for the treatment of carotid stenosis among patients at high risk for carotid endarterectomy. METHODS: Patients at high risk for carotid endarterectomy but amenable to percutaneous treatment with stent placement were enrolled. Clinical follow-up was performed at 30 days and 6 and 12 months postprocedure. The National Institutes of Health Stroke Scale was assessed before and within 3 days postprocedure and at 30 days and 6 months postprocedure. Angiography was performed pre- and postprocedure, and carotid duplex scans were performed at baseline and at 30 days and 6 months. RESULTS: Fifty-two carotid procedures were performed in 51 patients (mean age, 69 years; 84% of patients were men). The major adverse event (MAE) rate (death, stroke, and myocardial infarction [MI]) at 30 days was 5.9%: 2 strokes and a single death from periprocedural MI. MAE rates after 6 and 12 months were 5.9% and 11.8%, respectively. The delivery success rate was 94.2% (49/52) for the Interceptor Filter System and 95.9% (47/49) for the Exponent Stent. The mean diameter stenosis of the target lesion was reduced from 62.4% preprocedure to 21.2% postprocedure. CONCLUSION: High delivery success rates were achieved with a low rate of MAE (death, stroke, or MI) in a high-risk population. Treatment of carotid artery disease with the Exponent Carotid Stent combined with distal protection from the Interceptor Filter System is effective and safe.

Coronary restenosis after implantation of drug-eluting stents.

Randomized trials comparing drug-eluting stents (DES) with bare-metal stents have shown that the former significantly reduce the incidence of angiographic and clinical restenosis into an unprecedented low, one-digit, range. However, post-DES restenosis is not zero. Next to incomplete coverage with DES of the vessel segment injured by balloon angioplasty, factors such as stent underexpansion, stent overexpansion, and nonuniform distribution of stent struts have been associated with post-DES restenosis. Current evidence suggests that inadequate, though predominantly focal, delivery of the antiproliferative agent (sirolimus or paclitaxel) into the vessel wall is likely the common cause of post-DES restenosis. There is no consensus at present on how to treat post-DES restenosis. Long-term results reported to date on small numbers of patients undergoing interventional treatment for post-DES restenosis appear to be worse than outcomes observed after the index intervention, regardless of whether another DES was implanted or not, and warrant further study.

Evaluation of a balloon occlusion and aspiration system for protection from distal embolization during stenting in saphenous vein grafts.

Distal embolization after angioplasty in degenerated saphenous vein grafts (SVGs) results in high rates of periprocedural myonecrosis and mortality. Temporary protection of the distal microcirculation with aspiration of dislodged debris may improve the safety of SVG intervention. To evaluate the feasibility, safety, and efficacy of distal protection using the PercuSurge GuardWire Occlusion and Aspiration System, 103 consecutive patients undergoing planned stenting of 105 SVG lesions were prospectively enrolled in a multinational, multicenter study. Before angioplasty, protection of the distal circulation was achieved with the PercuSurge GuardWire distal balloon occlusion system, followed by stenting and debris aspiration. Quality assurance measures in the study included independent on-site data monitoring, clinical event adjudication, data analysis, and use of multiple core laboratories. Mean graft age was 8.9 +/- 4.0 years. The duration of distal balloon inflation was 5.4 +/- 3.7 minutes; premature balloon deflation for ischemia was not required in any patient. Macroscopically visible red and/or yellow debris was extracted in 91% of patients. By core lab analysis, postprocedural Thrombolysis In Myocardial Infarction-III flow was present in 98.9% of grafts (vs 83.5% before intervention). No patient developed angiographic evidence of no reflow or distal embolization. Postprocedural creatine phosphokinase MB isozyme levels were elevated to >3 x normal in only 5 patients (5%), and 97 patients (94%) were free of major adverse events at 30 days. We conclude that the GuardWire distal balloon occlusion and aspiration system is an effective and safe method for protecting distal microcirculation from the adverse consequences of embolization during mechanical intervention of degenerated SVGs.

Balloon-protected carotid artery stenting: relationship of periprocedural neurological complications with the size of particulate debris.

BACKGROUND: Carotid artery stenting (CAS) has been advocated as an alternative to endarterectomy. To prevent cerebral atheroembolism during CAS, distal balloon occlusion of the target artery increasingly is employed during the procedure. A correlation of the size of captured particles with the incidence of periprocedural neurological complications (PNCs) has not been attempted. METHODS AND RESULTS: In a 4-center, phase-1 trial, 54 patients (46 men; age, 69+/-8 years) underwent 58 CAS procedures using the PercuSurge GuardWire system for distal protection. Aspirated debris was sent for histological/cytological analysis. Stent placement was successful in all cases. Mean balloon occlusion time was 10.4+/-4.0 minutes (range, 3.0 to 22.0 minutes). Three patients (5.2%) experienced PNCs: 1 prolonged reversible ischemic neurological deficit that resolved in /=10 000 micrometer(2)) were found in 48 aspirates (83%). The median number of particles, their maximum diameter, and their maximum area were all significantly higher in the aspirates obtained during procedures associated with PNCs than in aspirates obtained during procedures not associated with PNCs. However, pronounced overlap in the distributions (PNCs versus no PNCs) of the number and maximum diameter of particles precluded any predictive inferences. In contrast, a maximum particle area >800 000 micrometer(2) (>0.8 mm(2)) was associated with a 60% chance of having a PNC. CONCLUSIONS: Despite balloon protection, PNCs occurred in 5.2% of patients who underwent CAS procedures. The maximum area of aspirated particles seems to be an indicator of increased risk for PNCs.

Influence of treatment modality on angiographic outcome after coronary stenting in diabetic patients: a controlled study.

OBJECTIVES: This retrospective study was designed to determine the six-month angiographic outcome after stenting of native coronary arteries in insulin-treated (ITDM) and non-ITDM patients with diabetes mellitus (DM) and compare the results with those in non-DM patients. BACKGROUND: The influence of the treatment modality for DM on restenosis in patients undergoing coronary artery stenting has not been elucidated sufficiently. METHODS: A total of 1,439 (70%) of 2,061 patients underwent repeated angiography within six months of coronary stenting. The ITDM and non-ITDM (oral hypoglycemic drugs or diet) were documented in 48 (3.3%) and 177 patients (12.3%), respectively, leaving 1,214 non-DM patients. RESULTS: Baseline reference vessel diameter tended to be smaller in ITDM patients (mean, 2.73 mm) than in non-DM and non-ITDM patients (2.88 mm and 2.85 mm, respectively). However, percent diameter stenosis was not different. The median number of stents deployed was 1; median stent length was 15 mm. Statistically significant differences were present after stenting for the means of minimal lumen diameter (MLD) and acute gain between ITDM patients (MLD: 2.67 mm, acute gain: 1.98 mm) and non-DM patients (MLD: 2.81 mm, acute gain: 2.16 mm). At follow-up, percent diameter stenosis, late lumen loss and loss index were significantly higher in both non-ITDM lesions (42%, 1.14 mm and 0.56, respectively) and ITDM lesions (48%, 1.26 mm and 0.65, respectively) than in non-DM lesions (35%, 0.96 mm and 0.45, respectively). The corresponding differences between non-ITDM and ITDM lesions did not reach statistical significance. Restenosis rates in non-DM, non-ITDM and ITDM lesions were 23.8%, 32.8% (p = 0.013 vs. non-DM) and 39.6% (p = 0.02 vs. non-DM, p = 0.477 vs. non-ITDM), respectively. CONCLUSIONS: This study showed that compared with stenting in non-DM patients, stenting of native coronary arteries in DM patients is associated with significantly increased lumen renarrowing, regardless of the treatment modality for DM.

Clinical outcome of patients with and without renal impairment undergoing a minimally invasive LIMA-to-LAD bypass operation.

PURPOSE: Patients with renal impairment undergoing conventional coronary artery bypass grafting (CABG) have a significant risk of postoperative deterioration of kidney function. We investigated the outcome of patients with and without renal impairment treated by off-pump coronary artery surgery. METHODS: From January 1997 until January 2000, 158 consecutive patients (mean age 63 +/- 9.8 years, 126 male, 32 female) underwent minimally LIMA-to-LAD bypass operations. The patients were divided into three groups: group I patients (n = 133) had a preoperative creatinine of < 1.3 mg/dL, group II patients (n = 21) had a creatinine of > 1.3 mg/dL, and patients of group III (n = 4) required chronic dialysis due to terminal kidney dysfunction. Monitoring of the blood creatinine was performed during the entire hospital stay. A postoperative angiogram was performed in 113 of the 158 patients. RESULTS: All operations were performed without intraoperative complications. Postoperative angiograms revealed a patent LIMA-to-LAD bypass in all but one patient, who demonstrated a dissection of the left internal mammary artery (LIMA) graft. Mean creatinine value on admission was 1.0 +/- 0.1 mg/dL in group I and 2.7 +/- 1.9 mg/dL in group II. The maximal postoperative creatinine value was 1.1 +/- 0.4 mg/dL in group I and 2.9 +/- 2.7 mg/dL in group II. Neither hemofiltration nor hemodialysis was necessary in any patient of group I or group II during the postoperative course. CONCLUSION: Minimally invasive LIMA-to-LAD bypass is a safe and effective procedure with low morbidity and no mortality in the first 158 patients. Preoperative renal impairment had no adverse effect on outcome or residual kidney function. Thus, higher doses of diuretics and hemofiltration/dialysis were not used, resulting in a cost reduction. Therefore, this approach may be worthwhile to consider in patients with significant renal impairment who have to undergo CABG.

Clinical and angiographic results with the ACS MULTI-LINK DUET trade mark Coronary Stent System - the DUET Study.

BACKGROUND: The DUET Study is a multicenter prospective efficacy and safety evaluation of the ACS MULTI-LINK DUET coronary stainless steel balloon-expandable stent. AIMS: The primary objective was to determine the one-month incidence of MACE (major adverse cardiac events). The secondary objectives were the acute success rate, the restenosis and reocclusion rates (assessed by quantitative coronary angiography (QCA)) at six months and the occurrence of MACE in hospital and at six months. METHODS: Two hundred and ten patients were enrolled between February and June 1998 in 18 European centers. Successful stent placement was achieved in 209 patients. All patients were treated with ticlopidine 500 mg/day for one month and with aspirin >/=100 mg/day. To allow the investigators to gain familiarity with the stent system, the first one to three patients per center formed a separate lead-in population leaving an intention-to-treat population of 157 patients. The majority of the intention-to-treat population were male (79%); 28% had unstable angina, 69% had stable angina, 44% had had a previous myocardial infarction, 15% had had a previous percutaneous transluminal coronary angioplasty, and 3% had a history of stroke. The target vessel was 38.5% left anterior descending artery, 20.5% left circumflex artery and 41.0% right coronary artery. RESULTS: All but one of the intention-to-treat patients were effectively stented (17 required multiple stents). Six-month angiographic follow-up was available in 90% of the intention-to-treat population. Minimal lumen diameter (MLD) postprocedure was 2.61 +/- 0.33 mm, with a residual diameter stenosis of 16%. Six-month follow-up data showed an MLD of 1.87 +/- 0.56 mm with a residual diameter stenosis of 36%. The binary restenosis rate (>/=50% residual stenosis) was 15.6%. Up to one month following the procedure 94.9% of the population was MACE-free, with two subacute occlusions. At six months all patients were alive, of whom 82.8% were MACE-free, and 73% were free of anginal complaints. CONCLUSION: The results observed in the current DUET registry are comparable to data of other balloon-expandable-stent trials, with a low incidence of clinical events at follow-up.

Restenosis after stenting of matched occluded and non-occluded coronary arteries. Should there be a difference?

AIMS: It is not known whether the higher restenosis rates reported after balloon angioplasty of occluded as opposed to non-occluded coronary arteries are still found after placement of coronary stents in lesions matched for factors known to affect late angiographic outcome. METHODS AND RESULTS: In a retrospective analysis of 1276 patients who had undergone coronary stent placement and in whom 6-month angiographic follow-up was available, we identified 144 patients with a total coronary occlusion which matched a non-occluded coronary lesion in another 144 patients. Matching lesion pairs were of the same type (de novo or restenotic), were supplied with the same type of stent, had reference vessel diameters identical within 0.3 mm and stented vessel segment lengths identical within 8 mm, and were located in corresponding target vessels. After stenting, statistically identical minimal lumen diameters had been achieved in both groups (occluded: 2.74+/-0.35 mm, non-occluded: 2. 77+/-0.32 mm, P = 0.45). At follow-up, minimal lumen diameters were not different (occluded: 1.65+/-0.77 mm, non-occluded: 1.76+/-0.76 mm, P = 0.24), reflecting an identical late lumen loss for occlusions (1.09+/-0.76 mm) and non-occluded lesions (1.01+/-0.70 mm, P = 0.38). Because of the significantly larger acute gain, the loss index was significantly lower for occluded vessels (0.40+/-0.27 vs 0. 51+/-0.35, P = 0.003). Corresponding restenosis rates were 33% (occluded) and 28% (non-occluded;P = 0.44). For stented vessel segment lengths >18 mm, restenosis rates were markedly higher (occluded: 42%, non-occluded: 36%) than for stented vessel segment lengths

Beating heart operations including hybrid revascularization: initial experiences.

BACKGROUND: The outcome of patients (n = 45) with coronary one- to three-vessel disease undergoing beating heart operations using a recently developed stabilizing device was investigated. METHODS: Left internal mammary artery-to-left anterior descending coronary artery (LIMA-to-LAD) revascularization was carried out alone (n = 31) or as hybrid procedure in combination with a balloon angioplasty (n = 14). RESULTS: All 45 patients underwent a successful LIMA-to-LAD procedure without intraoperative complication during a 21 +/- 8-minute (range, 10 to 53 minutes) LAD occlusion time. In 14 hybrid procedures a total of 19 stenoses including 3 left main stenoses were treated successfully by percutaneous transluminal coronary angioplasty and stenting. The postoperative courses were uneventful with the exception of two surgical reexplorations necessitated by bleeding. No worsening of renal, neurologic, or respiratory functions occurred in any patient. In the group having a single LIMA-to-LAD procedure, early postoperative coronary angiograms (22 of 31) showed a patent LIMA graft and excellent anastomosis; this was also true in 4 patients 12 months after operation as shown in angiograms. All patients undergoing hybrid revascularization demonstrated a patent LIMA-to-LAD anastomosis; in 1 patient there was a dissection in the midlevel of the LIMA, which was stented successfully. The 6-month follow-up angiograms in 7 of 14 patients revealed open LIMA bypass grafts in all patients except 1, who was stented because of dissection. CONCLUSIONS: These data indicate that a beating heart operation including hybrid revascularization is safe and effective in selected patients with coronary one- to three-vessel disease including left main stenosis. This approach may be especially advantageous in comparison with conventional coronary artery bypass grafting in patients with severe concomitant disease.

[First annual report of practitioners of interventional cardiology in private practice in Germany. Results of procedures of left heart catheterization and coronary interventions in the year 1996]. / Erster Jahresbericht niedergelassener Invasivkardiologen in Deutschland. Ergebnisse für diagnostische Linksherzkatheteruntersuchungen und Koronarinterventionen 1996.

The German Society for Cardiac Angiography and Interventions in Private Practice has started a registry of cardiac procedures since 1996 in order to establish a standard for performance. Although quality management for the cath lab makes sense and is also legally required, there is no generally recommended infrastructure for quality assurance existing in Germany at this time. Therefore, the German Society of Cardiologists in Private Practice (BNK) initiated a project in 1994 to develop a computer program for paperless documentation of diagnostic cardiac catheterizations and coronary interventions (PTCA) using a minimal data set. In 1996, 8 private associated groups participated in this project. The (anonymous) analysis of 10,316 diagnostic cardiac catheterizations and 2597 PTCA yielded the following results: In 95% of the patients, diagnostic cardiac catheterization was performed using the femoral and in 5% the brachial/radial approach. The mean volume of administered contrast medium was 164 +/- 138 ml/patient. The mean LV-EF was greater than 50% in 58.4% of the patients and between 30% and 50% in 10.1%. Coronary artery disease was diagnosed in 69.6% of the patients and valvular/congenital heart disease in 8.5%. In 18.4% of the patients undergoing diagnostic cardiac catheterizations no significant heart disease was identified. Mortality in the cath lab as well as the rate of cerebral insults was 0.05%. In 22.9% and 19% of the patients PTCA and cardiac surgery respectively was recommended. In patients undergoing PTCA, stable angina was present in 74.4% and unstable angina in 13.1%. Of the total number of PTCA procedures, 5.8% were performed in the setting of acute myocardial infarction. The PTCA lesion success rate was 96%, the mean diameter stenosis was 81% pre and 6% post-intervention. The mortality rate at 1 month post-PTCA was 0.4%, and myocardial infarction 1.0%. An acute occlusion occurred in 1.3% of the PTCA patients; 0.6% had to be transferred for emergency bypass surgery. None of the cath labs had on-site surgery. In comparison to other registries, our data show some similarities but also some different trends. Thus, our newly developed software proved to be reliable, fast and easy to use. Participating centers receive immediate feedback regarding their position within the whole group.

Stenting of nonacute total coronary occlusions: predictors of late angiographic outcome.

OBJECTIVES: This study was designed to determine and assess factors predictive of the intermediate-term outcome of stenting of nonacute total coronary occlusions. BACKGROUND: Balloon angioplasty of recanalized coronary occlusions is associated with a combined restenosis/reocclusion rate of up to 65%. Adjunctive stenting holds the potential to reduce this rate significantly. However, variables affecting the late angiographic outcome of coronary stenting in the setting of a total occlusion have not been elucidated sufficiently. METHODS: Coronary stenting was performed in 143 consecutive patients with a nonacute total occlusion; 120 of these patients (84%), with a total of 121 occlusions, underwent repeat angiography within 6 months and comprised the study group. High pressure stent implantation aimed to cover the site of the occlusion as well as adjacent diameter stenoses > or = 70% and all possibly induced dissections. Pertinent angiographic and procedural variables obtained at the time of the intervention were entered into a multivariate logistic regression analysis model to assess their influence on the angiographic outcome at follow-up. RESULTS: Mean preinterventional reference lumen diameter for the 121 vessels was 2.99 +/- 0.53 mm (mean +/- SD); occlusion length ranged from 4 to 44 mm (median of 7.7). After balloon angioplasty, dissections were found in 80% of patients. Lesions were covered with stents a median of 16 mm in length (range 8 to 53). The minimal lumen diameter (MLD) achieved after stenting was 2.89 +/- 0.48 mm. After a median follow-up period of 4.5 months, mean MLD was assessed at 1.91 +/- 0.90 mm, corresponding to a loss index of 0.34 +/- 0.31. There were 27 vessels with a nonocclusive restenosis > or = 50% and 8 with a reocclusion, for a combined restenosis/reocclusion rate of 29%. Factors found to adversely influence angiographic outcome were a post-stenting MLD < or = 2.54 mm, a stented vessel segment length > 16 mm, a balloon/vessel diameter ratio for final stent expansion < or = 1.00 and the presence of a dissection after balloon angioplasty. CONCLUSIONS: Compared with previous reports on stand-alone balloon angioplasty, stenting of nonacute total coronary occlusions lowers the 6-month restenosis/reocclusion rate to approximately 30%. The late procedural outcome is independently and statistically significantly influenced by the MLD after stenting, the length of the stented vessel segment, the balloon/vessel diameter ratio for final stent expansion and the incidence of dissections after balloon angioplasty.

Short-term results and intermediate-term follow-up of laser wire recanalization of chronic coronary artery occlusions: a single-center experience.

OBJECTIVES: This study sought to elucidate the short-term efficacy and intermediate-term outcome of excimer laser recanalization of chronic coronary artery occlusions in patients in whom attempts at mechanical revascularization had failed. BACKGROUND: Recanalization of chronic coronary occlusions with the use of a mechanical guide wire fails in 30% to 50% of cases, mostly because of inability to pass the wire through the lesion. The value of using excimer laser energy in this setting has not yet been determined. METHODS: The study group comprised 66 consecutive patients with 68 chronic coronary occlusions. Patients were eligible for inclusion in the study if a previous attempt at mechanical revascularization had failed and if their angiographic status was such that 1) the vessel segment distal to the occlusion could be visualized by way of collateral vessels, 2) the entry point of the occlusion was clearly outlined, and 3) not more than one anatomic bend was expected within the occlusion. Excimer laser energy was applied to the lesion through a 0.018-in. (0.046 cm) fiber-optic guide wire. Adjunctive balloon angioplasty and stenting were performed in all successfully treated patients but one. RESULTS: Thirty-four occlusions (50%) in 32 patients (48%) could be crossed with the laser wire. Location and age of the occlusion had no adverse influence on the outcome of laser wire recanalization, nor did the presence of bridging collateral vessels, a major side branch at the site of the lesion or a blunt stump of the occlusion. An inverse relation was found between the success rate and the length of the occlusion, such that a 19% reduction of the success rate accompanied each 10-mm increment of the mean occlusion length. Thus, the success rate was 68% for lesions < or = 10 mm but only 25% for lesions > 30 to < or = 40 mm. The presence of a bend in the lesion exceeding 60 degrees was strongly related to procedural failure. During a median angiographic follow-up period of 18 weeks, restenosis > 50% (n = 6) or reocclusion (n = 4) was found in 10 of the 32 successfully treated patients, for an intermediate-term success rate of 33% (22 of 66). Clinical follow-up revealed improved anginal status in 21 patients (66%) after a median of 24 weeks. Major complications (death, myocardial infarction, emergency operation) were not encountered. CONCLUSIONS: Successful recanalization of a chronic coronary occlusion by using currently available laser wires can be expected in 50% of selected patients in whom attempts at mechanical revascularization fail. Restenosis or reocclusion accounts for an overall 6-month success rate of 35%.

Comparison of immediate and intermediate-term results of intravascular ultrasound versus angiography-guided Palmaz-Schatz stent implantation in matched lesions.

BACKGROUND: Intravascular ultrasound (IVUS) provides more precise information than angiography about vascular dimensions. This information is used by some centers to optimize intracoronary stent implantation. There are no direct comparisons of the effects on restenosis of optimal IVUS-guided versus angiography-directed high-pressure stenting. METHODS AND RESULTS: Lesions of patients who had a 6-month angiographic follow-up study were eligible for matching. From 445 consecutive lesions treated by Palmaz-Schatz (P-S) stenting guided by IVUS (IVUS group) in Milan, 173 lesions were individually matched with 173 of 476 consecutive lesions treated by P-S stenting directed by angiography (Angio group) in Hamburg. Lesions were selected by a computerized program according to baseline clinical, angiographic, and procedural variables. Immediate and 6-month angiographic results were retrospectively compared, distinguishing an "early phase" from a "late phase." This distinction was based on the more aggressive dilation strategy with larger balloons and more demanding IVUS criteria for optimal stent expansion used in Milan in the early phase. In both phases, a larger minimum lumen diameter (MLD) immediately after stenting and after 6 months was achieved in the IVUS group than in the Angio group. In the early phase, the dichotomous restenosis rate was lower in the IVUS group than in the Angio group (9.2% versus 22.3%; P=.04). In the late phase, there was no difference in restenosis between the groups (22.7% versus 23.7%; P=1.0). CONCLUSIONS: In matched lesions treated with high-pressure stenting, IVUS guidance achieved a larger MLD than angiographic guidance. However, in the IVUS group, the restenosis rate was lower only in the early phase, when balloons larger than currently used were selected to maximize the stent lumen area.