Long-term Clinical Outcomes of DrugEluting Stent Malapposition

Previous pathologic, intravascular imaging, and clinical studies have investigated the association between adverse cardiac events and stent malapposition, including acute stent malapposition (ASM, that is detected at index procedure) and late stent malapposition (LSM, that is detected during follow-up) that can be further classified into late-persistent stent malapposition (LPSM, ASM that remains at follow-up) or late-acquired stent malapposition (LASM, newly developed stent malapposition at follow-up that was not present immediately after index stent implantation). ASM has not been associated with adverse cardiac events compared with non-ASM, even in lesions with large-sized malapposition. The clinical outcomes of LSM may depend on its subtype. The recent intravascular ultrasound studies with long-term follow-up have consistently demonstrated that LASM steadily increased the risk of thrombotic events in patients with first-generation drug-eluting stents (DESs). This association has not yet been identified in LPSM. Accordingly, it is reasonable that approaches to stent malapposition should be based on its relationship with clinical outcomes. ASM may be tolerable after successful stent implantation, whereas prolonged anti-thrombotic medications and/or percutaneous interventions to modify LASM may be considered in selected patients with first-generation DESs. However, these treatments are still questionable due to lack of firm evidences.

Multimodality Intravascular Imaging Assessment of Plaque Erosion versus Plaque Rupture in Patients with Acute Coronary Syndrome

BACKGROUND AND OBJECTIVES: We assessed plaque erosion of culprit lesions in patients with acute coronary syndrome in real world practice. SUBJECTS AND METHODS: Culprit lesion plaque rupture or plaque erosion was diagnosed with optical coherence tomography (OCT). Intravascular ultrasound (IVUS) was used to determine arterial remodeling. Positive remodeling was defined as a remodeling index (lesion/reference EEM [external elastic membrane area) >1.05. RESULTS: A total of 90 patients who had plaque rupture showing fibrous-cap discontinuity and ruptured cavity were enrolled. 36 patients showed definite OCT-plaque erosion, while 7 patients had probable OCT-plaque erosion. Overall, 26% (11/43) of definite/probable plaque erosion had non-ST elevation myocardial infarction (NSTEMI) while 35% (15/43) had ST elevation myocardial infarction (STEMI). Conversely, 14.5% (13/90) of plaque rupture had NSTEMI while 71% (64/90) had STEMI (p<0.0001). Among plaque erosion, white thrombus was seen in 55.8% (24/43) of patients and red thrombus in 27.9% (12/43) of patients. Compared to plaque erosion, plaque rupture more often showed positive remodeling (p=0.003) with a larger necrotic core area examined by virtual histology (VH)-IVUS, while negative remodeling was prominent in plaque erosion. Overall, 65% 28/43 of plaque erosions were located in the proximal 30 mm of a culprit vessel-similar to plaque ruptures (72%, 65/90, p=0.29). CONCLUSION: Although most of plaque erosions show nearly normal coronary angiogram, modest plaque burden with negative remodeling and an uncommon fibroatheroma might be the nature of plaque erosion. Multimodality intravascular imaging with OCT and VH-IVUS showed fundamentally different pathoanatomic substrates underlying plaque rupture and erosion.

Prospective and Systematic Analysis of Unexpected Requests for Non-Cardiac Surgery or Other Invasive Procedures during the First Year after Drug-Eluting Stent Implantation

PURPOSE: Unexpected requests for non-cardiac surgery requiring discontinuation of dual antiplatelet therapy (DAPT) frequently occur in daily clinical practice. The objectives of this study were to evaluate prevalence, timing and clinical outcomes of such unexpected requests for non-cardiac surgery or other invasive procedures during the first year after drug-eluting stents (DESs) implantation. MATERIALS AND METHODS: We prospectively investigated the prevalence, timing and clinical outcomes of unexpected requests for non-cardiac surgery or other procedures during the first year after DESs implantation in 2117 patients. RESULTS: The prevalence of requested non-cardiac surgery or invasive procedures was 14.6% in 310 requests and 12.3% in 261 patients. Among 310 requests, those were proposed in 11.3% <1 month, 30.0% between 1 and 3 months, 36.8% between 4 and 6 months and 21.9% between 7 and 12 months post-DES implantation. The rates of actual discontinuation of DAPT and non-cardiac surgery or procedure finally performed were 35.8% (111 of 310 requests) and 53.2% (165 of 310 requests), respectively. On multivariate regression analysis, the most significant determinants for actual discontinuation of DAPT were Endeavor zotarolimus-eluting stent implantation with 3-month DAPT (OR=5.54, 95% CI 2.95-10.44, p<0.001) and timing of request (OR=2.84, 95% CI 1.97-4.11, p<0.001). There were no patients with any death, myocardial infarction, or stent thrombosis related with actual discontinuation of DAPT. CONCLUSION: Those unexpected requests with premature discontinuation of DAPT were relatively common and continuously proposed during the first year following DES implantation. No death, myocardial infarction or stent thrombosis occurred in patients with actual discontinuation of DAPT.

First report of a novel abluminal groove filled biodegradable polymer rapamycin-eluting stent in de novo coronary artery disease: results of the first in man FIREHAWK trial / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Durable polymers used for first-generation drug-eluting stents (DES) potentially contribute to persistent inflammation and late DES thrombosis. We report the first in human experience with the rapamycin-eluting biodegradable polymer coated cobalt-chromium FIREHAWK stent with abluminal groove.</p><p><b>METHODS</b>A total of 21 patients with stable or unstable angina, or prior myocardial infarction, with single de novo native coronary stenoses < 30 mm in length in vessel sizes ranging from 2.25 to 4.0 mm were enrolled. The primary endpoint was major adverse cardiac events (MACE) at 30 days defined as the composite of cardiac death, myocardial infarction (Q and non-Q), or ischemia-driven target lesion revascularization. Secondary endpoints include device, lesion, and clinical success rates, 4-month in-stent late lumen loss by quantitative coronary angiography (QCA), proportion of uncovered or malapposed stent struts by optical coherence tomograpphy (OCT) at 4 months, and MACE at 4, 12, 24 and 36-month follow-up.</p><p><b>RESULTS</b>Device success was 95.7%, lesion and clinical success was 100.0%. There were no MACE events at 30 days. One patient died of non-cardiac hemorrhagic stroke 5 days after index procedure. At 4 months, in-stent late loss was (0.13 ± 0.18) mm, and complete strut coverage was 96.2% by OCT with 0.1% strut malapposition. At 4-month follow-up there was no additional MACE events, and a single target vessel (non-target lesion) revascularization.</p><p><b>CONCLUSIONS</b>The FIREHAWK abluminal groove biodegradable polymer rapamycin-eluting stent demonstrated feasibility, safety and efficacy in this first in human experience. OCT findings indicated excellent stent strut coverage 4 months after implantation. Larger studies are required to confirm whether the early FIREHAWK stent results translate into longer term restenosis and thrombosis benefits.</p>

Stenting of Unprotected Left Main Coronary Artery Stenosis without Anticogulation: Immediate and Late Outcomes

BACKGROUND: Recently, several reports regarding the protected and/or unprotected left main stenting suggested the possibility of percutaneous intervention for this prohibited area. We intented to evaluate immediate and long-term outcomes after elective stenting of unprotected left main coronary artery in selected patients. METHOD: Forty eight consecutive patients with unprotected left main coronary artery stenosis and normal left ventricular function were treated with stents implantation. The poststent antithrombotic regimen were aspirin, ticlopidine with warfarin in 14 pateints or without warfarin in 34 patients. The stents for left main coronary artery stenosis were Palmaz-Schatz stent in 25, NIR stent in 8, Multi-link stent in 3, Cordis stent in 7, Palmaz stent in 2, Gianturco-Roubin stent II in 2, and Microstent in 1 patient. Intravascular ultrasound was performed in selected patients before predilation and after stenting at late stage of this study. RESULTS: The procedural success rate was 100%. Regardless of anticoagulation, the in hospital complication including stent thrombosis, myocardial infarction, emergency bypass surgery and death did not occur. Six-months follow-up angiography was performed in 31 patients(82%) of 38 eligible patients. The angiographic restenosis occurred in 7 patients(22%) who subsequently underwent elective coronary bypass surgery in 5 patients and rotational atherectomy/balloon angioplasty in 2 patients. The target lesion revascularization rate was 18%. One death(3%) occurred 2 days after elective coronary bypass surgery during follow-up period. CONCLUSION: Stenting of unprotected left main coronary artery stenosis might be a safe and effective alternative to bypass surgery in carefully selected patients with normal left ventricular function. However, further clinical study should be needed for the late outcomes with larger numbers of patients.

"Late Clinical Outcomes of Cordis Tantalum Coronary Stenting without Anticoagulation : Validation of Angiographic Measurement and In-stent Restenosis by Intravascular Ultrasound"

BACKGROUND: The Cordis coronary stent is a flexible, balloon expandable, radiopaque tantalum stent. Previous reports have shown excellent initial clinical outcomes. To our knowledge, there is no report of the long-term clinical outcomes. The intensely radiopaque tantalum may interfere with the angiographic assessment. We intended to evaluate long-term clinical and angiographic restenosis rates after successful implantation of the Cordis tantalum coronary stent. METHOD: Two hundred and eighty-five consecutive patients with 300 lesions were treated with 366 Cordis stents. An angiographic follow-up substudy was performed in 190 lesions ; 6 month follow-up angiograms were available in 167(88%). At follow-up, intravascular ultrasound(IVUS) was performed to (1) determine the pattern of restenosis and (2) to validate the quantitative coronary angiographic(QCA) caliper measurements. RESULTS: IVUS and QCA caliper measurement of minimal luminal diameter correlated reliably (r=0.767, p<0.001). The QCA analysis detected diffuse in-stent restenosis more reliably than focal in-stent restenosis(p<0.01). The overall angiographic restenosis rate was 19%, The factors affecting angiographic restenosis were post-stent minimum lumen diameter, type C lesion, and reference vessel size. CONCLUSION: We concluded 1) The angiographic restenosis rate of Cordis stent was comparable to that of other slotted-tube stent. 2) The QCA caliper method is reliable for the assessment of Cordis in-stent restenosis, especially in the detection of diffuse in-stent restenosis. However, QCA may miss focal in-stent restenosis only detectable by IVUS

The Effects of Excimer Laser Coronary Angioplasty in Calcified Lesions : Investigation with Intravascular Ultrasound

BACKGROUND: Coronary artery target lesion calcification may be an important determinant of the arterial response to catheter therapy for coronary arterial disease. The excimer laser coronary angioplasty(ELCA) has been reported to be a promising treatment for complex coronary artery disease. However, the effects of ELCA is not well known against the calcified target lesion. METHODS: To assess the arterial and plaque remodeling in calcified lesions after excimer laser coronary angioplasty, we used a comprehensive intravascular ultrasound(IVUS) imaging system(25MHz rotation transducer, 3.9 Fr monorail imaging sheath, motorized transducer pull back at 0.5mm/sec and quantification) to study 23 patients(1 left main, 10 LAD, 4 LCX, 6 RCA, 2 SVG) before and immediately after ELCA(the AIS 308nm XeCl excimer laser, pulse width >200nsec, pulse frequency 20Hz, energy density 35-65mJ/mm2). Paired before and after ELCA image slices were analysed ; and extermal elastic membrane, lumen, plaque+media(P+M) and calcium cross-sectional area(CSA) measured; and their differences after ELCA calculated. RESULTS: The IVUS results about the therapeutic effects of ELCA showed the enlargement of lumen CSA from 1.5+/-0.4 to 3.2+/-0.9mm2(p<0.001) and decreased of P+M CSA from 14.6+/-3.8 to 13.4+/-3.6mm2(p<0.001) without arterial expansion. The decrease of calcium CSA from 1.8+/-0.7 to 1.5+/-0.6mm2(p<0.001) and the formation of small, superficial fissures within the calcified plaque(15/23 lesions) were noted. The number of small fissures correlate with the calcium CSA significantly(r=0.61, p<0.001). CONCLUSION: The plaque and calcium ablation is the main effects of ELCA in calcified lesion, and the calcium ablation and fissure formation after ELCA may contribute to decrease the dissection and improve the success after ajunctive PTCA.