"Hybrid" percutaneous and surgical coronary revascularization: selection criteria from a single-center experience.

BACKGROUND: The association of minimally invasive direct coronary artery bypass (MIDCAB) to percutaneous transluminal coronary angioplasty (PTCA) of large arteries with focal lesions can be an alternative therapeutic method for patients with multivessel coronary artery disease. We reviewed our experience regarding 42 patients treated at our Institute. METHODS: MIDCAB and PTCA of the circumflex or right coronary arteries > 3 mm were performed in 42 patients from September 1997 to December 1999. RESULTS: One patient died after MIDCAB in the operating room because of rupture of the left anterior descending anastomosis. Postoperative angiography confirmed patency of the internal mammary artery (IMA) graft in 92.3% of cases: 3 early IMA graft failures occurred. The success rate for PTCA was 98%: in 1 case the wire just would not cross a chronically and totally occluded right coronary artery. The in-hospital morbidity was 12.2%: 2 patients required urgent sternotomy respectively for cardiac tamponade and coronary artery bypass grafting on cardiopulmonary bypass. One patient developed atheroembolism after PTCA with recurrence of symptoms, progressive multiorgan failure and death. Two patients required PTCA on the IMA anastomosis because of early failure of the arterial graft. At a medium follow-up of 535 days, all 40 survivors are in Canadian Cardiovascular Society class I. CONCLUSIONS: Hybrid revascularization appears to be an effective treatment for selected patients with multivessel coronary artery disease. The immediate success seems related to the learning curve for MIDCAB.

Italian BiodivYsio open registry (BiodivYsio PC-coated stent): study of clinical outcomes of the implant of a PC-coated coronary stent.

UNLABELLED: Rapid technological developments have made new materials available for percutaneous coronary intervention procedures. The coronary stent in particular has undergone progressive structural improvements leading to the recent availability of a third generation of stents, namely, coated stents. The rapid evolution of the stent has often made its evaluation problematical, since trials are frequently confined to small groups of patients in single centers. The purpose of this registry was to verify the safety and efficacy of the BiodivYsio stent (a stent coated with phosphorylcholine polymer) in a broad population of patients who reflect the daily reality of coronary intervention in a cardiac catheterization laboratory. METHODS AND RESULTS: The registry was designed to collect the principal angiographic and clinical data of a consecutive series of Oreal worldO patients. Patients were treated with a BiodivYsio stent (Biocompatibles, Galway, United Kingdom) in 12 centers (11 Italian and 1 Swiss) between January 1998 and January 1999. Procedural, in-hospital, 30-day and six-month follow-up data were collected. The monitoring, data entry and statistical analyses were carried out by an independent center. During the study, 218 patients were enrolled; 165 (76%) male and 53 (24%) female, with an average age of 61.6 +/- 9.4 years (range, 36Eth 84 years). A total of 258 stents were implanted in 233 lesions (1.1 stents per lesion), of which 233 (90%) were the BiodivYsio PC coated stent, the remaining 25 implants were of other stent types. The percutaneous transluminal coronary angioplasty and stenting procedure were carried out in 109 (50%) patients with unstable angina, 65 (30%) with stable angina, 29 (13%) with acute myocardial infarction, and 15 (7%) patients with silent ischemia. Procedural success was achieved in 217/218 (99.5%) patients. Optimal results were achieved in 212 (97.7%) patients. In 34 (15.6%) cases, patients were treated with periprocedural abciximab. During the hospitalization period, one (0.4%) death occurred on day 7 due to subacute occlusion of the stent, and 3 (1.4%) myocardial infarctions were reported. At 30-day follow-up, 211 (97.2%) patients were asymptomatic, as were 189 (87%) patients at clinical follow-up at 6 months. CONCLUSIONS: This study evaluated the safety and efficacy of a third-generation stent. The results demonstrate a high procedural success rate and a low incidence of major adverse cardiac events at short- and medium-term follow-up. It appears that the BiodivYsio stent should be considered safe in clinical and/or anatomical situations with a high risk of complications, confirming the hypothesis that PC may have non-thrombogenic properties. To corroborate these results, an appropriately designed study would be required to measure the stentOs efficacy in the most suitable clinical context, i.e., clinical situations that are at the highest risk of ischemic relapse.

Percutaneous transluminal coronary revascularization in women: higher risk of dissection and need for stenting.

BACKGROUND: Even though success rates of percutaneous transluminal coronary angioplasty (PTCA) are influenced by gender, women are at higher risk for adverse procedural events. Plaque dissection has been demonstrated to cause more adverse cardiac events during PTCA in the female gender than the male, but it is not clear how much it could influence stent implantation and procedural complications in the stent era. This study sought to evaluate whether the prevalence of dissection is equal in men and women with similar vessel size, which factors are associated with the risk of this complication and whether stenting has modified the immediate outcome. METHODS: Three hundred thirty-nine lesions were studied in 100 consecutive women and 128 men with a vessel diameter < or = 3.5 mm, who underwent PTCA in our catheterization laboratory between March 1998 and March 1999. RESULTS: Procedural success rates were similar in the two groups (93.9% women vs 97.6% men). Complications were one coronary artery bypass graft and five acute myocardial infarctions. In the group of women, however, there was a significant increase in the incidence of plaque dissection during the procedure (37.9 vs 21.7%, p = 0.001), with consequent increased need for stenting (70.4 vs 52.2%, p < 0.05) to achieve adequate final results. Moreover, dissection was strongly associated (p = 0.03) with procedural complications. Multivariate analysis of the whole patient cohort showed the risk of dissection to be associated only with the female gender (p = 0.009), diabetes (p = 0.029), and type C lesion morphology (p = 0.019). CONCLUSIONS: Women are at higher risk of plaque dissection, which is associated with adverse procedural events and an increased need for stenting.

[Percutaneous coronary angioplasty in the elderly: a report of 2 cases in patients over 90]. / Angioplastica coronarica percutanea nei vecchi: descrizione di due casi in pazienti ultranovantenni.

Percutaneous transluminal coronary angioplasty is a validated method for coronary revascularization over coronary surgery in elderly patients. We describe two cases in patients in their nineties. Case n. 1: a 95-year-old patient with post-infarction angina that was not controlled well by medical therapy. On admission to our department, the patient was in good hemodynamic condition and a transthoracic echocardiographic examination confirmed normal left ventricular systolic function. Coronary angiography showed a severe calcified stenosis of the left anterior descending coronary artery, which was successfully treated with coronary angioplasty and stenting. After three months, the patient was readmitted because of angina. A new coronary angiogram showed diffuse in-stent restenosis, which was successfully treated with rotational atherectomy and angioplasty. The patient was asymptomatic at follow-up after 6 months. Case n. 2: a 91-year-old patient was admitted for an unstable angina. On admission to our department the patient was in good hemodynamic condition. Coronary angiography showed a severe stenosis of the left anterior descending coronary artery that was successfully treated with angioplasty and stenting. The patient was asymptomatic at 6-month follow-up. These cases show that coronary revascularization can successfully be performed even in patients in their nineties when medical therapy is unsuccessful and the patients are considered at high risk for surgery.

"Hybrid" and combined percutaneous and surgical intervention to treat selected cardiac patients: a new strategy.

The term "hybrid revascularization" describes the combined use of minimally-invasive surgery without cardiopulmonary bypass and percutaneous coronary revascularization in selected cases. The theoretical advantage of a less invasive surgical intervention must be weighted against the need for additional percutaneous procedures, with their own risks and limitations. We describe our initial experience with hybrid revascularization at the Istituto Clinico Humanitas in Milan. From 7/97 to 10/98, twelve patients underwent hybrid revascularization or a combined percutaneous and surgical intervention. A "classic" hybrid approach, consisting of minimally-invasive direct coronary artery bypass to the left anterior descending coronary artery and angioplasty or stenting of arteries in the right coronary artery or circumflex territories, was used in nine patients. In three patients, myocardial revascularization could be completed with percutaneous procedures after bypass surgery without cardiopulmonary bypass (in two patients because of severe aortic calcification) or valve surgery in a patient with two previous bypass operations. In-hospital complications were observed in three patients. Two required urgent median sternotomy (one for impending cardiac tamponade, one for conversion to bypass on extra-corporeal circulation). One patient developed atheroembolism after percutaneous intervention: after hospital discharge, there was a recurrence of symptoms, clinical deterioration with renal failure and eventually death. At a mean follow-up of 152 +/- 91 days (range 17 to 283) after minimally-invasive surgery and 166 +/- 122 days (range 13 to 397) after angioplasty, all surviving patients are well and free of anginal symptoms. Closer collaboration between surgical and interventional operators may offer a novel approach to effective treatment of difficult patient subsets. However, our initial experience suggests that a cautious evaluation of possible risks and benefits must carefully be entertained in each patient who may be considered a candidate for hybrid revascularization or combined percutaneous and surgical intervention.

Clinical feasibility of 0.018-inch intravascular ultrasound imaging device.

OBJECTIVES: Intravascular ultrasound imaging (IVUS) is limited by the size of the imaging catheter. To facilitate imaging before and during interventions, a 30-MHz ultrasonic imaging device was developed that is the same dimension as a 0.018-inch guide wire. The purpose of this study was to evaluate the clinical feasibility of this device. METHODS AND RESULTS: The imaging core was tested in 8 patients with the use of a monorail guiding sheath that was advanced through a 7F catheter. In addition, after coronary interventions, the standard guide wire was removed, the imaging core was placed inside a compatible balloon, and imaging was performed. In 4 patients, imaging was also performed with a standard 3.2F IVUS catheter. The lumen-plaque interface and the media-plaque interface were clearly visualized in all patients. There was no detectable loss in image quality between the new imaging device and the larger IVUS catheter, and measurements of lumen cross-sectional area were not statistically different. CONCLUSIONS: Improvements in manufacturing technology have permitted the development of a mechanically rotating ultrasound imaging core 0.018 inches in diameter. It is compatible with current balloon catheters without degradation of image quality.

Intracoronary stent implantation in native coronary arteries and saphenous vein grafts: a consecutive experience with six types of stents without prolonged anticoagulation.

OBJECTIVE: To analyze the results of implantation of six different intracoronary stents without the use of prolonged anticoagulation. MATERIAL AND METHODS: Between Mar. 30, 1993, and Jun. 30, 1995, 889 patients with 1,194 coronary or vein graft lesions underwent implantation of one of six types of stents-Palmaz-Schatz, Gianturco-Roubin, Wiktor, Micro, Cordis, or Wallstent. The patients were classified into seven groups on the basis of the type of stent that was implanted, including one group with combined use of two or more types of stents. Among the 851 patients with successful stent delivery and without major complications, 801 received only antiplatelet therapy, and 50 received a standard anticoagulation regimen. One-month clinical followup data were obtained in all patients, and clinical events were investigated. RESULTS: The mean number of stents was 1.8 per lesion and 2.4 per patient. Procedural success was achieved in 93% of the lesions. The clinical success rate at 1 month was 90%. Intravascular ultrasound assessment was performed in 90% of the lesions. The final minimal luminal cross-sectional area of the stent increased from 6.8 to 7.8 mm2 after intravascular ultrasound-guided optimization. Within 1 month, 16 stent thrombosis events (1.9%) occurred. No significant differences were noted in stent thrombosis rates among the various stent cohorts. Multivariate logistic regression analysis revealed that the final stent minimal luminal diameter measured by intravascular ultrasonography was the only variable associated with stent thrombosis. CONCLUSION: This study showed that six different stents could possibly be inserted without subsequent anticoagulation if optimal stent expansion and total lesion coverage were achieved.

High pressure assisted coronary stent implantation accomplished without intravascular ultrasound guidance and subsequent anticoagulation.

OBJECTIVES: The purpose of this study was to determine the efficacy of treatment with antiplatelet therapy and no anticoagulation after high pressure assisted coronary stent implantation performed without intravascular ultrasound (IVUS) guidance. BACKGROUND: Previous studies have shown that during IVUS-guided Palmaz-Schatz coronary stenting, it is safe to withhold anticoagulation when stent expansion has been optimized by high pressure balloon dilation. METHODS: Patients that had successful coronary stenting without IVUS guidance were treated with ticlopidine, 500 mg/day, and aspirin, 325 mg/day, for 1 month and then received only aspirin, 325 mg/day, indefinitely. Patients were not treated with warfarin (Coumadin) or heparin after successful stenting. Clinical and angiographic events were assessed at 1 month. RESULTS: A total of 201 intracoronary stents were implanted in 127 patients with 137 lesions. The average number of stents per lesion was 1.4 +/- 0.8, and the average number of stents per patient was 1.6 +/- 1.1. Stent deployment was performed for elective indications in 79% of procedures and for emergency indications in 21%. There were four stent thrombosis events for a per patient event rate of 3.1% and a per lesion event rate of 2.9%. CONCLUSIONS: After high pressure assisted stenting performed without IVUS guidance, there was an acceptable incidence of 3.1% of stent thrombosis with the combination of short-term ticlopidine and aspirin therapy and no anticoagulation. Although the study involved only 127 patients, the results support the relative safety of stenting without IVUS guidance and with antiplatelet therapy only in comparison to historical trials on stenting performed with postprocedure anticoagulation.

[The evaluation of the acute recoil of the Palmaz-Schatz stent using echography. A case report]. / Valutazione del "recoil" acuto dello stent di Palmaz-Schatz mediante ecografia. Descrizione di un caso.

Intravascular ultrasound, performed using a 0.018 in guide wire with a 30 MHz ultrasound transducer, allows to study the acute recoil of Palmaz-Schatz stent. This case showed that the acute recoil of the Palmaz-Schatz stent occurs immediately after stent implantation. The analysis of diameter and lumen cross-sectional area at the stent site was performed at different levels of dilatation. A 20% reduction of cross-sectional area was found immediately after stent expansion and balloon deflation.

Successful closure of a coronary vessel rupture with a vein graft stent: case report.

We report a successfully percutaneous closure of a brisk coronary artery rupture with a custom-made "vein graft stent," a Palmaz-Schatz stent covered with a vein graft. This method is an elegant and effective alternative to the traditional surgical approach and should be considered whenever technically and clinically feasible.

Implantation of the peripheral Wallstent for diffuse lesions in coronary arteries and vein grafts.

The Wallstent (Schneider, Bulach, Switzerland) is available in different lengths without much compromise in flexibility and radial support compared to some other stents. We treated 24 patients (26 vessels) with diffuse coronary lesions or vein graft lesions with intravascular ultrasound-guided peripheral Wallstent implantation. Average balloon pressure during stent optimization was 16.4 +/- 2.7 atm. The stents could be successfully implanted in 24 vessels. Minimal lumen diameter and percent diameter stenosis after stenting were 3.60 +/- 0.62 mm and -8 +/- 13%, respectively. Average stent length was 63.7 +/- 22.7 mm. There was one procedure-related complication. After stenting, all patients were treated only with antiplatelet agents. During 1-month follow-up, there was one subacute stent thrombosis due to incomplete coverage of a distal dissection. These preliminary results show the feasibility of this novel approach in selected lesions.

Acute recoil of Palmaz-Schatz stent: a rare cause of suboptimal stent implantation--report of two cases with intravascular ultrasound findings.

It is generally believed that the Palmaz-Schatz stent maintains a strong radial force, preventing stent recoil. However, the capacity to prevent recoil is largely governed by the hardness or resistance of the lesion. We report two cases of "acute Palmaz-Schatz stent recoil," documented by intravascular ultrasound, and suggest a novel treatment of this unusual problem.

A randomized comparison of combined ticlopidine and aspirin therapy versus aspirin therapy alone after successful intravascular ultrasound-guided stent implantation.

BACKGROUND: Previous studies have shown that it is feasible to withhold anticoagulation after a successful intracoronary stent procedure with a low incidence of stent thrombosis. The importance of specific antiplatelet agents when stenting is performed without anticoagulation is unknown. METHODS AND RESULTS: After successful intravascular ultrasound-guided stenting, 226 patients were randomly assigned to receive either aspirin therapy alone (n = 103) or a combination of ticlopidine and short-term aspirin therapy (n = 123). Primary angiographic and clinical end points were stent thrombosis, death, myocardial infarction, the need for postprocedure coronary artery bypass surgery or repeated angioplasty, and significant medication side effects requiring termination of the medication within the first month of a successful procedure. At 1 month, the rate of stent thrombosis was 2.9% in the aspirin only group and 0.8% in the ticlopidine-aspirin group (P = .2). Cumulative major clinical events after successful stenting occurred in 3.9% of the patients in the aspirin group and in 0.8% in the ticlopidine-aspirin group (P = .1). There were no medication side effects in the aspirin group; in the combined ticlopidine-aspirin group, medication side effects occurred in 3 patients (P = .2). CONCLUSIONS: At 1 month, there was no difference in the incidence of stent thrombosis or other clinical end points between the two poststent antiplatelet regimens. However, the relatively small size of the study and the low incidence of thrombosis events may have contributed to the failure to detect differences in angiographic and clinical end points between the two groups.

Intracoronary stent insertion after balloon angioplasty of chronic total occlusions.

OBJECTIVES: This retrospective analysis was performed to assess the medium-term effectiveness of implanting intracoronary stents into chronic total occlusions that are successfully opened by balloon angioplasty. BACKGROUND: The value of percutaneous transluminal coronary angioplasty of chronic total occlusions is limited by a very high restenosis rate of 50% to 68%. Intravascular stents have been shown to reduce restenosis in a subset of patients with subtotal stenoses. It has not been demonstrated that the placement of stents into successfully opened chronic total coronary artery occlusions leads to lower rates of restenosis. METHODS: A consecutive series of patients with chronic total coronary occlusions successfully opened by balloon angioplasty received Palmaz-Schatz stents. Patients underwent clinical and angiographic follow-up at a mean of 6 months after stent insertion. Angiographic and clinical results were retrospectively analyzed. RESULTS: Fifty-nine patients underwent stenting of 60 chronic total coronary occlusions, with a 98% rate of successful stent deployment. Complications occurred in 5% of cases, all with subacute thrombosis. Angiographic follow-up was obtained in 88% of patients at a mean of 6 months and demonstrated an angiographic restenosis rate of 20%, with only one reocclusion. Among several variables examined, only the presence of a procedure-related moderate to severe dissection was associated with higher follow-up percent diameter stenoses and clinical events. At a mean of 14 months after stent insertion, 77% of patients remained free of symptoms or clinical events. CONCLUSIONS: The implantation of intracoronary stents into vessels with opened chronic total coronary occlusions is associated with favorable rates of angiographic restenosis and relief of symptoms. A randomized clinical trial comparing balloon angioplasty with stent-assisted balloon angioplasty in the treatment of chronic total coronary occlusions is indicated.

Techniques for Palmaz-Schatz stent deployment in lesions with a large side branch.

Palmaz-Schatz coronary stent implantation in lesions with a large side branch are reported. The first case describes how to manage plaque shifting after stent implantation. The second and third cases demonstrate a kissing balloon predilatation and stent dilatation technique of a bifurcational lesion. The final case demonstrates a stent implantation technique through the stent struts of a previously deployed stent.

Intracoronary stenting without anticoagulation accomplished with intravascular ultrasound guidance.

BACKGROUND: The placement of stents in coronary arteries has been shown to reduce restenosis in comparison to balloon angioplasty. However, clinical use of intracoronary stents is impeded by the risk of subacute stent thrombosis and complications associated with the anticoagulant regimen. To reduce these complications, the hypothesis that systemic anticoagulation is not necessary when adequate stent expansion is achieved was prospectively evaluated on a consecutive series of patients who received intracoronary stents. METHODS AND RESULTS: From March 1993 to January 1994, 359 patients underwent Palmaz-Schatz coronary stent insertion. After an initial successful angiographic result with < 20% stenosis by visual estimation had been achieved, intravascular ultrasound imaging was performed. Further balloon dilatation of the stent was guided by observation of the intravascular ultrasound images. All patients with adequate stent expansion confirmed by ultrasound were treated only with antiplatelet therapy (either ticlopidine for 1 month with short-term aspirin for 5 days or only aspirin) after the procedure. Clinical success (procedure success without early postprocedural events) at 2 months was achieved in 338 patients (94%). With an inflation pressure of 14.9 +/- 3.0 atm and a balloon-to-vessel ratio of 1.17 +/- 0.19, optimal stent expansion was achieved in 321 of the 334 patients (96%) who underwent intravascular ultrasound evaluation, with these patients receiving only antiplatelet therapy after the procedure. Despite the absence of anticoagulation, there were only two acute stent thromboses (0.6%) and one subacute stent thrombosis (0.3%) at 2-month clinical follow-up. Follow-up angiography at 3 to 6 months documented two additional occlusions (0.6%) at the stent site. At 6-month clinical follow-up, angiographically documented stent occlusion had occurred in 5 patients (1.6%). At 6-month clinical follow-up, there was a 5.7% incidence of myocardial infarction, a 6.4% rate of coronary bypass surgery, and a 1.9% incidence of death. Emergency intervention (emergency angioplasty or bailout stent) for a stent thrombosis event was performed in 3 patients (0.8%). The overall event rate was relatively high because of intraprocedural complications that occurred in 16 patients (4.5%). Intraprocedural complications, however, decreased to 1% when angiographically appropriately sized balloons were used for final stent dilations. There was one ischemic vascular complication that occurred at the time of the procedure and one ischemic vascular complication that occurred at the time of angiographic follow-up. By 6 months, repeat angioplasty for symptomatic restenosis was performed in 47 patients (13.1%). CONCLUSIONS: The Palmaz-Schatz stent can be safely inserted in coronary arteries without subsequent anticoagulation provided that stent expansion is adequate and there are no other flow-limiting lesions present. The use of high-pressure final balloon dilatations and confirmation of adequate stent expansion by intravascular ultrasound provide assurance that anticoagulation therapy can be safely omitted. This technique significantly reduces hospital time and vascular complications and has a low stent thrombosis rate.

Clinical and angiographic outcome after Palmaz-Schatz stent implantation guided by intravascular ultrasound.

Intracoronary stents can be implanted with a low incidence of stent thrombosis (< 1%) when the stent procedure is guided by intravascular ultrasound. The long-term clinical and angiographic effects, however, have not been reported. This study assesses the 6 month clinical and angiographic results of a consecutive series of patients with intravascular ultrasound guided Palmaz-Schatz stent deployment that were not treated with subsequent anticoagulation after a successful stent implantation procedure. From March, 1993 to April 1994, 411 patients underwent Palmaz-Schatz stent implantation. There were 26 patients that had uncomplicated Palmaz-Schatz stent implantation that were treated with a standard anticoagulation regimen that are not evaluated in this study. Thus, this study includes an assessment of 385 patients that had either a successful intravascular ultrasound guided stent implantation procedure and did not receive post procedure anticoagulation or had a procedural complication. Procedural success was achieved in 369 patients (96%). Clinical success (procedure success without early post procedure event) was achieved in 363 patients (94%). There were 2 acute stent thrombosis events (0.5%) and 1 subacute stent thrombosis (0.3%) in the group of 369 patients with 454 lesions treated without anticoagulation. At 6 month clinical follow-up the incidence of myocardial infarction was 4.9% and the rate of coronary bypass surgery was 6.2%. There was a 2.1% incidence of death. Emergency intervention (emergency angioplasty or bailout stent implantation was necessary in 3 patients (0.8%). The total incidence of repeat percutaneous intervention was 11.4%. By 6 months clinical follow-up, major events had occurred in 19.2% of patients. The angiographic lesion restenosis rate, according to 50% diameter stenosis criteria, was 19%. The incidence of restenosis per patient was 22%. In conclusion, intravascular ultrasound guided Palmaz-Schatz can be performed without subsequent anticoagulation with a low incidence of stent thrombosis and acceptable clinical and angiographic outcome at 6 month clinical follow-up.

Benefit of intracoronary ultrasound in the deployment of Palmaz-Schatz stents.

OBJECTIVES: This study was designed to evaluate the changes in intrastent and angiographic dimensions when intravascular ultrasound imaging is used to direct the deployment of balloon-expandable Palmaz-Schatz stents in coronary arteries and saphenous vein grafts. BACKGROUND: Intravascular ultrasound provides more information than angiography in the imaging of intravascular structures. Previous studies have shown that obtaining a larger lumen (greater "acute gain") with coronary interventions such as stenting leads to less restenosis and subacute thrombosis. It is not clear whether the information obtained by intravascular ultrasound can be used to obtain a greater acute gain in lumen dimensions. METHODS: Forty consecutive patients undergoing Palmaz-Schatz stent implantation had intravascular ultrasound imaging performed after a good angiographic appearance was obtained. If the stent did not appear adequately expanded by intravascular ultrasound, or if the struts were poorly apposed to the arterial wall, further stent dilation with larger balloons or higher pressure inflations were performed. Twenty-nine patients had subsequent intravascular ultrasound imaging. Intrastent diameters and areas were compared from the initial to the final intravascular ultrasound studies. RESULTS: Of the 40 patients studied, only 5 (13%) had an adequate result by intravascular ultrasound despite an acceptable angiographic appearance in all patients. Six additional patients did not undergo subsequent intravascular ultrasound imaging. The other 29 patients all demonstrated a significant increase in intrastent minimal diameter (mean 19%), major diameter (11%) and cross-sectional area (34%) (p < 0.001 for all measurements). CONCLUSIONS: The use of intravascular ultrasound imaging in the deployment of balloon-expandable Palmaz-Schatz stents leads to a significant increase in intrastent dimensions (greater "acute gain").

Favourable results of treatment of narrowed saphenous vein grafts with Palmaz-Schatz stent implantation.

Although conventional balloon angioplasty of saphenous vein grafts can be performed with an acceptable acute success and complication rate, restenosis remains a major problem. However, this may be overcome by the implantation of Palmaz-Schatz stents. Palmaz-Schatz stent deployment was performed in our institution in 43 patients who were referred for PTCA of stenosed saphenous vein grafts. Thirty-seven were located at the mid-portion of the graft, seven at the ostium and six at the distal anastomosis. Overall, we used 59 standard length (15 mm) Palmaz-Schatz stents and 22 short (7 mm) stents. In 15 lesions (30%) multiple stents were implanted in tandem to treat diffuse disease. Angiographic success was achieved in 47 of the 50 attempted lesions (94%). Major cardiac complications occurred in three patients. Two patients had procedures complicated by the development of a Q wave myocardial infarction, one of whom underwent urgent CABG. One patient died. There was no episode of subacute thrombosis. The angiographic follow-up of 37 lesions (80% of eligible lesions) at a mean time of 5 +/- 2 months (range 1-8) showed a restenosis rate of 11% and residual post-stent diameter stenosis was associated with a significantly higher restenosis rate. However, no restenosis occurred in lesions receiving multiple stents. Clinical follow-up was performed in all patients, and at a mean of 25 months after the procedure, 64% were free from clinical events, including recurrent angina. Palmaz-Schatz stent implantation is an effective and safe procedure to treat narrowed vein grafts.(ABSTRACT TRUNCATED AT 250 WORDS)