Risk Of Subacute Stent Thrombosis Research Articles

A Novel guide extension assisted stenting technique for coronary bifurcation lesions.

A challenging technical scenario frequently encountered in a percutaneous coronary intervention of a coronary bifurcation lesion (CBL) is stent implantation of only the stenosed segment without compromising the other two normal segments in non-true bifurcation lesions. Another is precise stent implantation covering the side branch ostium without leaving excessive stent metal at the other two segments of a bifurcation lesion in complex true bifurcation lesions. The aim of this study was to describe a novel stenting technique for both non-true and true CBLs by using a guide extension catheter (GuideLiner). With the assistance of a guide extension catheter mounted on both the main and the side-branch guidewires and with its intubation down to the bifurcation carina, a stent can be implanted in the side branch segment or distal main segment of the bifurcation lesion appropriately without compromising the other two segments of the coronary bifurcation. Stent implantation is described in three bifurcation lesions in three cases and shown in detail with illustrative figures. The technique facilitates side-branch only stenting in side-branch mono-ostial (medina 0, 0, 1) CBL or only the distal main segment in distal mono-ostial (medina 0, 1, 0) CBL without compromising the other two remaining segments when using the one-stent technique in non-true CBLs without leaving unnecessary excessive stent metal at the bifurcation site and when using a two-stent technique in complex true bifurcation lesions (tri-ostial or medina 1, 1, 1). Consequently, through optimizing stent deployment, the technique may have the potential to reduce the risk of subacute stent thrombosis and future in-stent restenosis. The most appropriate lesions suitable for the technique, and some other practical tips are also described.

Anti-platelet drugs, pharmacogenomics and stent thrombosis: What’s new?

Stent thrombosis is a catastrophic complication of percutaneous coronary intervention (PCI) and is associated with a mortality of 25 to 40%. The perception that stent thrombosis is very low in all patients has resulted in a lack of adherence to professional guidelines. New data to identify patients at increased risk for stent thrombosis are emerging. Clopidogrel is a prodrug and the activation of clopidogrel is dependent on CY2C19. Numerous alleles of CYP2C19 exist. The allele CYP2CP*2 has been associated with a marked decrease in platelet responsiveness to clopidogrel. Heterozygote carriers of the CYP2C19*2 have a 2.7 fold increased risk and homozygotes a 4.8 fold increased risk of stent thrombosis. Prospective randomised clinical trials will be necessary to determine the efficacy of CYP2C19 genotype directed therapy in evidence-based clinical decision making. Point-of-care platelet-function tests are becoming available and some centres are now performing such tests on their PCI patients. The most recent AHA/ACC /SCAI guidelines recommend testing for clopidogrel responsiveness in patients at high risk of subacute stent thrombosis and recommend increasing the dose of clopidogrel in non-responders.

Use of bioresorbable vascular scaffold: a meta-analysis of patients with coronary artery disease.

BackgroundDifferences in outcomes between bioresorbable vascular scaffold (BVS) systems and drug-eluting metal stents (DES) have not been fully evaluated. We aimed to compare clinical and angiographic outcomes in randomised studies of patients with coronary artery disease (CAD), with a secondary analysis performed among registry studies.MethodsA meta-analysis comparing outcomes between BVS and DES in patients with CAD. Overall estimates of treatment effect were calculated with random-effects model and fixed-effects model.ResultsIn 6 randomised trials (3818 patients), BVS increased the risk of subacute stent thrombosis (ST) over and above DES (OR 2.14; CI 1.01 to 4.53; p=0.05), with a trend towards an increase in the risk of myocardial infarction (MI) (125 events in those assigned to BVS and 50 to DES; OR 1.36; CI 0.97 to 1.91; p=0.07). The risk of in-device late lumen loss (LLL) was higher with BVS than DES (mean difference 0.08 mm; CI 0.03 to 0.13; p=0.004). There was no difference in the risk of death or target vessel revascularisation (TVR) between the two devices. In 6 registry studies (1845 patients), there was no difference in the risk of death, MI, TVR or subacute ST between the two stents. Final BVS dilation pressures were higher in registry than in randomised studies (18.7±4.6 vs 15.2±3.3 atm; p<0.001).ConclusionsPatients treated with BVS had an increased risk of subacute ST and slightly higher LLL compared with those with DES, but this might be related to inadequate implantation techniques, in particular device underexpansion.

Everolimus-eluting bioresorbable vascular scaffolds versus everolimus-eluting metallic stents: a meta-analysis of randomised controlled trials

Bioresorbable coronary stents might improve outcomes of patients treated with percutaneous coronary interventions. The everolimus-eluting bioresorbable vascular scaffold is the most studied of these stent platforms; however, its performance versus everolimus-eluting metallic stents remains poorly defined. We aimed to assess the efficacy and safety of everolimus-eluting bioresorbable vascular scaffolds versus everolimus-eluting metallic stents in patients with ischaemic heart disease treated with percutaneous revascularisation. We searched Medline, Embase, the Cochrane Central Register of Controlled Trials (CENTRAL), scientific sessions abstracts, and relevant websites for randomised trials investigating everolimus-eluting bioresorbable vascular scaffolds versus everolimus-eluting metallic stents published or posted between Nov 30, 2006, and Oct 12, 2015. The primary efficacy outcome was target lesion revascularisation and the primary safety outcome was definite or probable stent (scaffold) thrombosis. Secondary outcomes were target lesion failure (the composite of cardiac death, target-vessel myocardial infarction, or ischaemia-driven target lesion revascularisation), myocardial infarction, death, and in-device late lumen loss. We derived odds ratios (ORs) and weighted mean differences with 95% CIs, and calculated the risk estimates for the main outcomes according to a random-effects model. This study is registered with PROSPERO, number CRD42015026374. We included six trials, comprising data for 3738 patients randomised to receive percutaneous coronary intervention with either an everolimus-eluting bioresorbable vascular scaffold (n=2337) or an everolimus-eluting metallic stent (n=1401). Median follow-up was 12 months (IQR 9-12). Patients treated with bioresorbable vascular scaffolds had a similar risk of target lesion revascularisation (OR 0.97 [95% CI 0.66-1.43]; p=0.87), target lesion failure (1.20 [0.90-1.60]; p=0.21), myocardial infarction (1.36 [0.98-1.89]; p=0.06), and death (0.95 [0.45-2.00]; p=0.89) as those treated with metallic stents. Patients treated with a bioresorbable vascular scaffold had a higher risk of definite or probable stent thrombosis than those treated with a metallic stent (OR 1.99 [95% CI 1.00-3.98]; p=0.05), with the highest risk between 1 and 30 days after implantation (3.11 [1.24-7.82]; p=0.02). Lesions treated with a bioresorbable vascular scaffold had greater in-device late lumen loss than those treated with a metallic stent (weighted mean difference 0.08 [95% CI 0.05-0.12]; p<0.0001). Compared with everolimus-eluting metallic stents, everolimus-eluting bioresorbable vascular scaffolds had similar rates of repeat revascularisation at 1 year of follow-up, despite inferior mid-term angiographic performance. However, patients treated with a bioresorbable vascular scaffold had an increased risk of subacute stent thrombosis. Studies with extended follow-up in a larger number of patients are needed to fully assess the long-term advantages of everolimus-eluting bioresorbable vascular scaffolds. None.

Prolonged Infusion of Eptifibatide as Bridge Therapy Between Bare‐Metal Stent Insertion and Cardiovascular Surgery: Case Report and Review of the Literature

Dual antiplatelet therapy with aspirin and clopidogrel is the standard of care after coronary artery stent insertion. Clopidogrel, however, has been associated with an increased risk of bleeding if it is used before coronary artery bypass grafting (CABG), and current guidelines recommend that it be discontinued at least 5 days before surgery. Compared with dual antiplatelet therapy, single antiplatelet therapy or the combination of an antiplatelet agent and an anticoagulant is associated with an increased risk of subacute stent thrombosis. Management of patients who require semiurgent CABG after stent insertion presents a clinical challenge. Intravenous glycoprotein IIb-IIIa inhibitors provide antiplatelet coverage with a shorter duration of action; thus, in theory, they may be useful for these clinical situations. We describe a 47-year-old man who came to the emergency department with sudden-onset, retrosternal chest pain. An electrocardiogram confirmed a diagnosis of ST-segment elevation myocardial infarction. The patient underwent angioplasty and received a bare-metal stent. Because significant disease was revealed in other arteries, CABG was scheduled. Clopidogrel was discontinued in preparation for surgery, and the patient received an infusion of eptifibatide 2 microg/kg/minute as bridging therapy to surgery for a total of 9 days. No major hemorrhagic or clinically evident thrombotic complications occurred before or after the surgery. Eptifibatide may be safe and effective as bridging therapy for patients with intracoronary stents who require CABG.

Coronary artery bifurcation lesion classifications, interventional techniques and clinical outcome

Percutaneous coronary intervention for the treatment of bifurcation lesions is associated with a lower success rate and increased risk of subacute stent thrombosis and restenosis. The goal of this manuscript is to review the current classification of coronary bifurcation lesions and techniques. An algorithmic approach for the treatment of bifurcation lesions based on the recently published simplified and comprehensive classification is proposed in this manuscript.

Simultaneous double-culprit in-stent thrombosis. Who is the guilty prisoner behind bars: drug-eluting stent, bare-metal stent, or indication for treatment?

The intrinsic thrombogeneity of stents was the historic limitation to their usage during the early phases of stenting. The risk of stent thrombosis has been minimized by the widespread use of platelet antiaggregation. Nowadays, the risk of subacute stent thrombosis is around 1%. Thrombotic risk depends on several factors, such as type of stent, complexity of lesion, and clinical picture. We present a case of recurrent acute in-stent thrombosis in a patient with mild antithrombin III (AT) deficiency despite the combined administration of clopidogrel and aspirin. In our patient, several factors, such as diabetes, AT deficiency, and the use of a paclitaxel-eluting stent, have contributed to the development of recurrent acute stent thrombosis. Although we were not able to identify the culprit factor, we should keep in mind that the deployment of a drug-eluting stent could be unsafe if it is not supported by a clear clinically oriented pathway that considers the overall condition of the patient since, in some cases, neither coronary lesions nor coronary stents are responsible for the negative outcome of patient therapy, which may be caused instead by incomplete or inadequate patient assessment.

Postprocedural low molecular weight heparin in patients at high risk of subacute stent thrombosis*1

Subacute stent thrombosis (SAT) is a dramatic complication of percutaneous coronary stenting occurring in 0.4–20% of cases depending on several angiographic and clinical variables. The role of postprocedural low molecular weight heparin (LMWH) in preventing early events after high-risk PCI is not well established. In this study we describe our experience with postprocedural LMWH in patients deemed to be at high risk of SAT. Thirty-six patients who were treated with subcutaneous LMWH for at least 7 days after the intervention were identified from our database. All cineangiograms and charts were retrospectively reviewed to confirm the high-risk intervention properties. Thirty-day and long-term major adverse coronary events (MACEs) were documented in all patients. The most common indications for LMWH were the deployment of ≥3 consecutive stents, the presence of intracoronary thrombus or ulceration, poststenting residual stenosis, contraindication to aspirin or thienopyrideines, and persistent dissection. The majority of patients (61%) had ≥2 risk factors. Mean postprocedural treatment period was 12±3 days. At 30 days, none of the patients experienced a MACE including death, myocardial infarction, and repeat revascularization. No major bleeding occurred and one patient (2.7%) had a minor bleeding. At a mean follow-up of 31 months, MACE occurred in 17% of patients. Postprocedural LMWH is safe and effective in preventing SAT in patients undergoing high-risk coronary intervention.

Postprocedural low molecular weight heparin in patients at high risk of subacute stent thrombosis

Background Subacute stent thrombosis (SAT) is a dramatic complication of percutaneous coronary stenting occurring in 0.4–20% of cases depending on several angiographic and clinical variables. The role of postprocedural low molecular weight heparin (LMWH) in preventing early events after high-risk PCI is not well established. In this study we describe our experience with postprocedural LMWH in patients deemed to be at high risk of SAT. Methods Thirty-six patients who were treated with subcutaneous LMWH for at least 7 days after the intervention were identified from our database. All cineangiograms and charts were retrospectively reviewed to confirm the high-risk intervention properties. Thirty-day and long-term major adverse coronary events (MACEs) were documented in all patients. Results The most common indications for LMWH were the deployment of ≥3 consecutive stents, the presence of intracoronary thrombus or ulceration, poststenting residual stenosis, contraindication to aspirin or thienopyrideines, and persistent dissection. The majority of patients (61%) had ≥2 risk factors. Mean postprocedural treatment period was 12±3 days. At 30 days, none of the patients experienced a MACE including death, myocardial infarction, and repeat revascularization. No major bleeding occurred and one patient (2.7%) had a minor bleeding. At a mean follow-up of 31 months, MACE occurred in 17% of patients. Conclusions Postprocedural LMWH is safe and effective in preventing SAT in patients undergoing high-risk coronary intervention.

The Early Result of Primary NIR Stenting in Acute Myocardial Infarction

Background and Objectives:The intracoronary stent may be useful in the preventing of abrupt closure and coronary restenosis after coronary angioplasty, and recently primary stenting has been one of therapeutic modalities. We assessed the clinical and angiographic results of primary NIR stenting in patients with acute myocardial infarction (AMI). Materials and Methods:Between November 1997 to January 1999, 55 stentings with NIR stents were done in 51 patients with acute myocardial infarction. Angiographic follow-up was available at 7±2.3 days in 35 patients. Results:1) Among 51 patients (M/F:37/14), 44 patients had Qwave MI (86%), 7 patients had non-Q-wave MI (14%). 2) The mean age was 61±12.4 years (range:26 to 82 years). 3) The mean time from the onset of chest pain to the arrival at emergency room was 4.6±4.2 hours. The mean door-to-balloon time was 93±46 minutes 4) Treated vessels were as follows;28 in LAD, 17 in RCA, 10 in LCX. 5) The indications for stent implantation were suboptimal angiographic results after PTCA in 38 lesions (69%), dissection in 9 lesions (16%), abrupt vessel closure in 1 lesion and elective in 7 lesions (13%). 6) Single stent implantation was done in 47 patients. Overlapping stents were done in 4 patients. 7) A procedure related complication occurred in one patient, peri-stent dissection without flow limitation. 8) Full expansion of the stent failed in three lesions with coronary calcifications and the residual stenosis was 35, 40, 50% in each case. In these cases, in-stent thrombus was not demonstrated in follow up angiography. 9) The minimal lumen diameter increased from 0.11±0.39 to 2.96±0.40 mm. 10) Angiographic follow-up on 38 stents in 35 patients demonstrated in-stent thrombus in 3 stents, in-stent restenosis in 1 stent. But in-stent flow limitations were not found in these 4 cases and TIMI III flow were maintained. Patients with Q-wave MI and coronary thrombus on initial angiography were more prone to subacute thrombosis. Conclusion:The NIR stent could be used successfully in primary coronary stenting in acute myocardial infarction. The present study shows relatively low risk of subacute stent thrombosis. The rate of restenosis needs to be confirmed by long term study. (Korean Circulation J 2000;30(5):563-570)

Direct coronary stenting without predilation

OBJECTIVESCoronary stenting is the primary therapeutic option for percutaneous treatment of many coronary lesions, after the risk of subacute stent thrombosis and bleeding complications has been reduced by improved antithrombotic regimens and high pressure stent expansion.BACKGROUNDDirect stent implantation (without predilation) has been considered a promising new technique that may reduce the procedure time, radiation exposure time and cost.METHODSAfter having reviewed all cases of stent implantation from February to June 1998 (n = 585), 185 (32%) of these patients were retrospectively considered candidates for direct stent implantation without predilation, according to prespecified criteria (i.e., absence of severe coronary calcifications and/or tortuosity of the lesion or the segment proximal to the lesion). By operator preference, direct coronary stent implantation was actually attempted in 123 (21%) of the 585 patients (100 men, 60 ± 10 years old) on 123 lesions. The impact of direct stenting in terms of cost, procedure time, radiation exposure time and amount of contrast dye used was assessed by comparing the two groups of patients who underwent single-vessel stenting without (n = 69) and with (n = 46) predilation.RESULTSDirect stenting was successful in 118 patients (96%). No acute or subacute complications occurred in these patients. Procedure time, radiation exposure time and cost were significantly lower in the group of patients who had single-vessel direct versus conventional stenting (45 ± 31 vs. 64 ± 46 min, 12 ± 9 vs. 16 ± 10 min and 1,305 ± 363 vs. 2,210 ± 803 Euro, respectively; p < 0.05 for all).CONCLUSIONSDirect stenting without predilation in selected lesions seems to be a safe and successful procedure that provides a way to contain cost and to shorten radiation exposure time.

Diagnosing coronary arterial stent thrombosis and arterial closure

This single-center review of a consecutive series of patients requiring reexamination by angiography within 1 week of a coronary stent placement due to chest pain reveals that patients treated with a poststent anticoagulation regimen of warfarin and aspirin, and those with lower poststent deployment dilation pressures, have an increased risk of subacute stent thrombosis. Repeat cardiac catheterization within the first week after coronary artery stent implantation should be reserved for patients with significant electrocardiographic changes.