Effect of Stent Inflation Pressure and Post-Dilatation on the Outcome of Coronary Artery Intervention. A Report of More than 90 000 Stent Implantations

Background

Percutaneous coronary intervention (PCI) stent inflation pressure correlates to angiographic lumen improvement and stent expansion but the relation to outcome is not clarified. Using comprehensive registry data our aim was to evaluate how stent inflation pressure influences restenosis, stent thrombosis and death following PCI.

Methods

We evaluated all consecutive coronary stent implantations in Sweden during 46 months from 2008 using data from the Swedish Coronary Angiography and Angioplasty Registry (SCAAR). We used logistic regression and Cox proportional hazard modeling to estimate risk of outcomes with different balloon pressures.

Results

In total, 93 697 stents were eligible for analysis and divided into five different pressure interval groups: ≤15 atm, 16–17 atm, 18–19 atm, 20–21 atm and ≥22 atm. The risks of stent thrombosis and restenosis were significantly higher in the ≤15 atm, 18–19 atm and ≥22 atm groups (but not in the 16–17 atm group) compared to the 20–21 atm group. There were no differences in mortality. Post-dilatation was associated with a higher restenosis risk ratio (RR) of 1.22 (95% confidence interval (CI) 1.14–1.32, P<0.001) but stent thrombosis did not differ statistically between procedures with or without post-dilatation. The risk of death was lower following post-dilatation (RR 0.81 (CI 0.71–0.93) P = 0.003) and the difference compared to no post-dilatation was seen immediately after PCI.

Conclusion

Our retrospective study of stent inflation pressure identified a possible biological pattern—the risks of stent thrombosis and of restenosis appeared to be higher with low and very high pressures. Post-dilatation might increase restenosis risk.     

The Impact of SYNTAX Score of Non-Infarct-Related Artery on Long- Term Outcome among Patients with Acute ST Segment Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention

Objective

We investigated the impact of the severity of stenosis in a non-infarct-related artery (IRA) on the long-term prognosis of patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI).

Methods

Three hundred one consecutive patients (age: 59.7 ± 13.2 years, 85.5% men) underwent primary PCI during 2009–2012. Receiver operating characteristic curve analysis found the optimal cutoff for non-IRA SYNTAX score (SS) to be 2.5. We divided the patients into two groups according to this cutoff value.

Results

By multivariable analysis, non-IRA SS (≥2.5) was an independent predictor of major adverse cardiac events (hazard ratio [HR]: 2.15, 95% confidence interval [CI]: 1.21–3.79, P  =  0.008) and all-cause mortality (HR: 3.49, 95% CI: 1.13–10.8, P  =  0.03). However, the prediction of cardiovascular mortality had only borderline significance (HR: 3.29, 95% CI: 0.90–12.08, P  =  0.07).

Conclusion

STEMI patients treated with primary PCI and moderate to severe non-IRA stenosis (SS ≥2.5) have more subsequent cardiac events. Those populations should be treated with more aggressive preventive and medical management.     

Six-month clinical outcomes of the Tryton Side Branch Stent for the treatment of bifurcation lesions

Aims

Percutaneous coronary intervention (PCI) of a bifurcation lesion (BL) is still associated with poorer clinical outcomes when compared with PCI of a non-BL. Therefore, several dedicated coronary bifurcation stents, such as the Tryton Side Branch Stent™ (Tryton Medical, Durham, NC, USA), were developed to improve clinical outcomes. We investigated 6-month clinical outcomes after placement of a Tryton stent in 91 patients treated for 93 BLs in our centre.

Methods and results

All consecutive patients who have undergone PCI of a BL treated with the Tryton stent in our centre were included. Outcomes were defined as any death, cardiac death, myocardial infarction (MI), any revascularisation, ischaemia-driven target vessel revascularisation (TVR), ischaemia-driven target lesion revascularisation (TLR), stent thrombosis, and target vessel failure (TVF; composite of cardiac death, MI, and ischaemia-driven TVR). Event rates were estimated using the Kaplan-Meier method. Thirty-eight (42 %) patients with acute coronary syndrome (ACS) were included (16 % ST-segment elevation MI (STEMI)). The 6-month event rates were 5.4 % (death), 4.3 % (cardiac death), 2.2 % (MI), 4.5 % (any revascularisation), 4.5 % (TVR), 4.5 % (TLR) and 9.7 % (TVF).

Conclusion

In a real-world all-comers single-centre registry, the use of the Tryton Side Branch Stent was associated with acceptable procedural and promising clinical outcomes at 6 months, including ACS and STEMI patients.     

Drug-Eluting versus Bare-Metal Stent for Treatment of Saphenous Vein Grafts: A Meta-Analysis

Background

Saphenous vein grafts develop an aggressive atherosclerotic process and the efficacy of drug eluting stents (DES) in treating saphenous vein graft (SVG) lesions has not been convincingly demonstrated. The aim of this study was to review and analyze the current literature for controlled studies comparing DES versus bare metal stents (BMS) for treatment of SVG stenoses.

Methodology/Principal Findings

We searched several scientific databases and conference proceedings up to March 15, 2010 for controlled studies comparing target vessel revascularization (TVR) between DES and BMS. Summary odds ratios (OR) for the primary endpoint TVR and secondary endpoints infarction, stent thrombosis and death were calculated using random-effect models. A total of 29 studies (3 randomized controlled trials RCT) involving 7549 (202 in RCT) patients were included. The need for target vessel revascularization in the DES group tended to be lower compared to BMS for the 3 RCT (OR 0.50 [0.24–1.00]; p = 0.051) and for observational studies (0.62 [0.49–0.79]; p<0.001). There was no significant difference in the risk for myocardial infarction in the RCT (OR 1.25 [0.22–6.99]; p = 0.250) but a lower risk for DES based on the observational studies 0.68 [0.49–0.95]; p = 0.023. The risk for stent thrombosis was found to be non-different in the RCT (OR 0.78 [0.03–21.73], p = 0.885) while it was in favor of DES in the observational studies (0.58 [0.38 – 0.84]; p<0.001). The mortality was not significantly different between DES and BMS in the RCT''s (OR 2.22 [0.17 – 29.50]; p = 0.546) while the observation studies showed a decreased mortality in the DES group (0.69 [0.55–0.85]; p<0.001).

Conclusion

DES may decrease TVR rate in treatment of SVG stenoses. No differences in reinfarction rate, stent thrombosis or mortality was found between the DES and BMS groups in the RCT''s while the observational data showed lower risk for myocardial infarction, stent thrombosis and death in the DES group. This may be a result of patient selection bias in the observational studies or represent a true finding that was not the detected in the RCT analysis due to limited statistical power.     

Effect of Pioglitazone on In-Stent Restenosis after Coronary Drug-Eluting Stent Implantation: A Meta-Analysis of Randomized Controlled Trials

Background

In-stent restenosis (ISR) remains a common life-threatening complication and some studies have shown that pioglitazone can reduce the incidence of ISR in patients with drug-eluting stents (DES) implantation. We conducted a meta-analysis to assess the effect of pioglitazone in preventing ISR after DES implantation.

Methods

Randomized controlled trials (RCTs) investigating the effects of pioglitazone for ISR after DES implantation were identified by systematic searches of multiple online databases and manual searches of related reference lists of identified trials through May 2014. The primary endpoint was the rate of ISR. Secondary endpoints included minimum lumen diameter, percentage stenosis of stented vessels, late loss, in-stent neointimal volume, target vessel revascularization (TVR), target lesion revascularization, myocardial infarction, stent thrombosis and death.

Results

Five studies, comprising 255 pioglitazone-treated patients and 245 controls, were identified in the current meta-analysis. Pioglitazone did not significantly reduce the rate of ISR (P = 0.20) with low heterogeneity (I² = 13.3%, P = 0.32). For the secondary outcomes, pioglitazone did not substantially affect the pooled estimates of these endpoints except late loss (P = 0.01) and TVR (P = 0.04).

Conclusions

The limited evidence indicates that pioglitazone does not demonstrate markedly beneficial effect in patients subjected to coronary DES implantation. However, the results should be interpreted with care given the small sample size. Further large-scale RCTs are needed.     

Hemodynamic Effects of Stent Struts versus Straightening of Vessels in Stent-Assisted Coil Embolization for Sidewall Cerebral Aneurysms

Background

Recent clinical studies have shown that recanalization rates are lower in stent-assisted coil embolization than in coiling alone in the treatment of cerebral aneurysms.

Objective

This study aimed to assess and compare the hemodynamic effect of stent struts and straightening of vessels by stent placement on reducing flow velocity in sidewall aneurysms, with the goal of reducing recanalization rates.

Methods

We evaluated 16 sidewall aneurysms treated with Enterprise stents. We performed computational fluid dynamics simulations using patient-specific geometries before and after treatment, with or without stent struts.

Results

Stent placement straightened vessels by a mean (±standard deviation) of 12.9°±13.1° 6 months after treatment. Placement of stent struts in the initial vessel geometries reduced flow velocity in aneurysms by 23.1%±6.3%. Straightening of vessels without stent struts reduced flow velocity by 9.6%±12.6%. Stent struts had significantly stronger effects on reducing flow velocity than straightening (P = 0.004, Wilcoxon test). Deviation of the effects was larger by straightening than by stent struts (P = 0.01, F-test). The combination of stent struts and straightening reduced flow velocity by 32.6%±12.2%. There was a trend that larger inflow angles produced a larger reduction in flow velocity by straightening of vessels (P = 0.16).

Conclusion

In sidewall aneurysms, stent struts have stronger effects (approximately 2 times) on reduction in flow velocity than straightening of vessels. Hemodynamic effects by straightening vary in each case and can be predicted by inflow angles of pre-operative vessel geometry. These results may be useful to design a treatment strategy for reducing recanalization rates.     

Impact of Coronary Dominance on In-Hospital Outcomes after Percutaneous Coronary Intervention in Patients with Acute Coronary Syndrome

Objective

This study evaluated the manner in which coronary dominance affects in-hospital outcomes of acute coronary syndrome (ACS) patients undergoing percutaneous coronary intervention (PCI).

Background

Previous studies have shown that left dominant coronary anatomies are associated with worse prognoses in patients with coronary artery disease.

Methods

Data were analyzed from 4873 ACS patients undergoing PCI between September 2008 and April 2013 at 14 hospitals participating in the Japanese Cardiovascular Database Registry. The patients were grouped based on diagnostic coronary angiograms performed prior to PCI; those with right- or co-dominant anatomy (RD group) and those with left-dominant anatomy (LD group).

Results

The average patient age was 67.6±11.8 years and both patient groups had similar ages, coronary risk factors, comorbidities, and prior histories. The numbers of patients presenting with symptoms of heart failure, cardiogenic shock, or cardiopulmonary arrest were significantly higher in the LD group than in the RD group (heart failure: 650 RD patients [14.7%] vs. 87 LD patients [18.8%], P = 0.025; cardiogenic shock: 322 RD patients [7.3%] vs. 48 LD patients [10.3%], P = 0.021; and cardiopulmonary arrest: 197 RD patients [4.5%] vs. 36 LD patients [7.8%], P = 0.003). In-hospital mortality was significantly higher among LD patients than among RD patients (182 RD patients [4.1%] vs. 36 LD patients [7.8%], P = 0.001). Multivariate logistic regression analysis revealed that LD anatomy was an independent predictor for in-hospital mortality (odds ratio, 1.75; 95% confidence interval, 1.06–2.89; P = 0.030).

Conclusion

Among ACS patients who underwent PCI, LD patients had significantly worse in-hospital outcomes compared with RD patients, and LD anatomy was an independent predictor of in-hospital mortality.     

CYP2C19 Phenotype,Stent Thrombosis,Myocardial Infarction,and Mortality in Patients with Coronary Stent Placement in a Chinese Population

Background

Several studies have indicated that CYP2C19 loss-of-function polymorphisms have a higher risk of stent thrombosis (ST) after percutaneous coronary interventions (PCIs). However, this association has not been investigated thoroughly in a Chinese population. In this study, we aimed to determine the effect of CYP2C19*2 and CYP2C19*3 loss-of-function polymorphisms on the occurrence of ST and other adverse clinical events in a Chinese population.

Methods

We designed a cohort study among 1068 consecutive patients undergoing intracoronary stent implantation after preloading with 600 mg of clopidogrel. CYP2C19*2 and CYP2C19*3 were genotyped by using polymerase chain reaction-restriction fragment length polymorphism analysis. The adverse clinical events recorded were ST, death, myocardial infarction (MI), and bleeding events. The primary end point of the study was the incidence of cumulative ST within 1 year after PCI. The secondary end point was other adverse clinical outcomes 1 year after the procedure.

Results

The cumulative 1-year incidence of ST was 0.88% in patients with extensive metabolizers (EMs) (CYP2C19*1/*1 genotype), 4.67% in patients with intermediate metabolizers (IMs) (CYP2C19*1/*2 or *1/*3 genotype), and 10.0% in patients with poor metabolizers (PMs) (CYP2C19*2/*2, *2/*3, or *3/*3 genotype) (P<0.001). The one-year event-free survival was 97.8% in patients with EMs, 96.5% in patients with IMs, and 92.0% in patients with PMs (P = 0.014). Multivariate analysis confirmed the independent association of CYP2C19 loss-of-function allele carriage with ST (P = 0.009) and total mortality (P<0.05).

Conclusion

PM patients had an increased risk of ST, death, and MI after coronary stent placement in a Chinese population.     

Red Blood Cell Distribution Width and Long-Term Outcome in Patients Undergoing Percutaneous Coronary Intervention in the Drug-Eluting Stenting Era: A Two-Year Cohort Study

Background

Previous studies suggest the higher the red blood cell distribution width (RDW) the greater the risk of mortality in patients with coronary artery disease (CAD). However, the relationship between RDW and long-term outcome in CAD patients undergoing percutaneous coronary intervention (PCI) with a drug-eluting stent (DES) remains unclear. This study was designed to evaluate the long-term effect of RDW in patients treated with drug-eluting stent for CAD.

Methods

In total of 2169 non-anemic patients (1468 men, mean age 60.2±10.9 years) with CAD who had undergone successful PCI and had at least one drug-eluting stent were included in this study. Patients were grouped according to their baseline RDW: Quartile 1 (RDW<12.27%), Quartile 2 (12.27%≤RDW<13%), Quartile 3 (13%≤RDW<13.5%), and Quartile 4 (RDW≥13.5).

Results

The incidence of in-hospital mortality and death or myocardial infarction was significantly higher in Quartiles 3 and 4 compared with Quartile 1 (P<0.05). After a follow-up of 29 months, the incidence of all-cause death and stent thrombosis in Quartile 4 was higher than in Quartiles 1, 2, and 3 (P<0.05). The incidence of death/myocardial infarction/stroke and cardiac death in Quartile 4 was higher than in Quartiles 1 and 2 (P<0.05). Multivariate Cox regression analysis showed that RDW was an independent predictor of all-cause death (hazard ratio (HR) = 1.37, 95% confidence interval (CI) = 1.15–1.62, P<0.001) and outcomes of death/myocardial infarction/stroke (HR = 1.21, 95% CI = 1.04–1.39, P = 0.013). The cumulative survival rate of Quartile 4 was lower than that of Quartiles 1, 2, and 3 (P<0.05).

Conclusion

High RDW is an independent predictor of long-term adverse clinical outcomes in non-anemic patients with CAD treated with DES.     

Increased Risk for Developing Major Adverse Cardiovascular Events in Stented Chinese Patients Treated with Dual Antiplatelet Therapy after Concomitant Use of the Proton Pump Inhibitor

Background

Some clinical studies have demonstrated that the proton pump inhibitor (PPI) could decrease clopidogrel platelet response and increase major adverse cardiovascular events (MACE) in white or black subjects. However, that remains to be determined in Chinese patients. In this study, we sought to determine whether there could be an increased risk for developing MACE after concomitant use of dual antiplatelet therapy (DAT) and a PPI in Chinese patients treated with percutaneous coronary intervention (PCI) and stenting.

Methods

This study was a 5-year, single-center, retrospective cohort analysis of eligible patients (n = 6188) who received DAT and a PPI concomitantly (defined as PPI users) before discharge and/or 12-month follow-up after discharge as compared with those who received DAT alone (also defined as non-PPI users, n = 1465). The incidence of recurrent MACE, such as myocardial infarction (MI), definite stent thromboses (ST), or cardiovascular death, was compared between the PPI users and non-users.

Results

PPI users had a significantly higher incidence of the MACE than non-users (13.9% vs. 10.6%; adjusted HR: 1.33; 95% CI: 1.12 – 1.57, P = 0.007). Stratified analysis revealed that concurrent use of DAT and a PPI was associated with a significantly increased risk for developing ST compared with DAT alone (1% vs. 0.4%; adjusted HR: 2.66, 95% CI: 1.16 – 5.87, P = 0.012). However, there were no significant differences in the risk of MI, cardiovascular death and other adverse events, regardless of combination of clopidogrel and a PPI.

Conclusions

The study further suggests that concomitant use of DAT and a PPI may be associated with an increased risk for developing MACE, in particular definite ST, in Chinese PCI patients after discharge as compared with use of DAT alone.     

Reconstructive Treatment of Ruptured Intracranial Spontaneous Vertebral Artery Dissection Aneurysms: Long-Term Results and Predictors of Unfavorable Outcomes

Introduction

Few studies focused on predictors of unfavorable outcomes (modified Rankin Scale, 2–6) after reconstructive treatment of the ruptured intracranial spontaneous vertebral artery dissection aneurysms (ris-VADAs), which was evaluated based on 57 reconstructed lesions in this study.

Methods

Results of 57 consecutive patients (M:F = 29∶28; median age, 48 years; range, 27 to 69 years) harboring 57 ris-VADAs, which were treated with coils combined with single stent(n = 32), double overlapping stents (n = 16), and triple overlapping stents (n = 9) between October 2000 to March 2011, were retrospectively reviewed and analyzed.

Results

The available (n = 54) mean durations of angiographic and clinical follow-ups were 27 months (range, 12 to 78) and 62 months (range, 12 to 132), respectively. The involvement of PICA (p = 0.004), size of lesions (p = 0.000), quantity of stent (p = 0.001), and coil type (p = 0.002) affected the immediate obliteration grade, which was only risk factor for angiographic recurrences (p = 0.031). Although the post-treatment outcomes did not differ between single stent and multiple stents (p = 0.434), 5 angiographic recurrences, 1 rebleeding and 1 suspected rebleeding, all occurred in partial obliteration after single-stent-assisted coiling. Progressive thrombosis and in-stent obliteration were not detected on follow-up angiograms. Older age (odds ratio [OR] = 1.090; 95% confidence interval [CI], 1.004–1.184; p = 0.040) and unfavorable Hunt-Hess scale (OR = 4.289; 95%CI, 1.232–14.933; p = 0.022) were independent predictors of unfavorable outcomes in the reconstructed ris-VADAs.

Conclusions

Immediate obliteration grade was only risk factor for angiographic recurrence after reconstructive treatment. Unfavorable Hunt-Hess grade and older age were independent predictors of unfavorable outcomes in ris-VADAs.     

Impact of the Distance from the Stent Edge to the Residual Plaque on Edge Restenosis following Everolimus-Eluting Stent Implantation

Objectives

This study aimed to assess the relation between stent edge restenosis (SER) and the distance from the stent edge to the residual plaque using quantitative intravascular ultrasound.

Background

Although percutaneous coronary intervention with drug-eluting stents has improved SER rates, determining an appropriate stent edge landing zone can be challenging in cases of diffuse plaque lesions. It is known that edge vascular response can occur within 2 mm from the edge of a bare metal stent, but the distance to the adjacent plaque has not been evaluated for drug-eluting stents.

Methods

A total of 97 proximal residual plaque lesions (plaque burden [PB] >40%) treated with everolimus-eluting stents were retrospectively evaluated to determine the distance from the stent edge to the residual plaque.

Results

The SER group had significantly higher PB (59.1 ± 6.1% vs. 51.9 ± 9.1% for non-SER; P = 0.04). Higher PB was associated with SER, with the cutoff value of 54.74% determined using receiver operating characteristic (ROC) curve analysis. At this cutoff value of PB, the distance from the stent edge to the lesion was significantly associated with SER (odds ratio = 2.05, P = 0.035). The corresponding area under the ROC curve was 0.725, and the cutoff distance value for predicting SER was 1.0 mm.

Conclusion

An interval less than 1 mm from the proximal stent edge to the nearest point with the determined PB cutoff value of 54.74% was significantly associated with SER in patients with residual plaque lesions.     

Clinical Presentations,Antiplatelet Strategies and Prognosis of Patients with Stent Thrombosis: An Observational Study of 140 Patients

Background

Until now there has been scarce evidence regarding an optimal antiplatelet strategy and clinical outcomes for patients who had suffered from stent thrombosis (ST).

Methods and Results

140 patients who suffered from stent thrombosis were prospectively registered. Patients received dual (aspirin and 150 mg clopidogrel, N = 66) or triple (additional cilostazol, N = 74) antiplatelet therapy at the physician’s discretion. Thereafter platelet reactivity and one year clinical outcomes were analyzed. The primary outcome included the composite of cardiac death, non-fatal myocardial infarction (MI) or stroke at one year,which developed in 41 (29.3%) patients, consisting of 31 (22.1%) cardiac death, 9 (6.4%) non-fatal MI and 1 (1.4%) stroke. Recurrent definite and probable ST according to ARC definition was observed in 8 (5.7%) and 14 (10.0%) patients, respectively. Triple therapy was associated with significantly lower platelet reactivities (50.2±17.8, % vs. 59.6±17.2, %, P = 0.002) compared to high dose dual antiplatelet therapy. However, the incidence of primary events (24.3% vs. 34.8%, P = 0.172) did not differ between triple and dual antiplatelet therapies. High on-treatment platelet reactivity (HR: 8.35, 95% CI: 2.234∼30.867, P = 0.002) and diabetes (HR: 3.732, 95% CI: 1.353∼10.298, P = 0.011) were independent predictors of primary events.

Conclusions

Patients who suffered from stent thrombosis have a poor prognosis even after revascularization with intensive antiplatelet therapy. Triple antiplatelet therapy was more effective in reducing on-treatment platelet reactivity, compared to high dose dual antiplatelet therapy.     

Relationship of Glycated Hemoglobin Levels with Myocardial Injury following Elective Percutaneous Coronary Intervention in Patients with Type 2 Diabetes Mellitus

Background

Glycated hemoglobin (HbA1c) predicts clinical cardiovascular disease or cardiovascular mortality. However, the relationship between HbA1c and myocardial injury following elective percutaneous coronary intervention (PCI) in patients with type 2 diabetes mellitus (DM) has not been investigated.

Objectives

The study sought to assess the relationship between HbA1c and myocardial injury following elective PCI in patients with type 2 DM.

Methods

We studied a cohort of consecutive 994 diabetic patients with coronary artery disease (CAD) undergoing elective PCI. Periprocedural myocardial injury was evaluated by analysis of troponin I (cTnI). The association between preprocedural HbA1c levels and the peak values of cTnI within 24 hours after PCI was evaluated.

Results

Peak postprocedural cTnI >1×upper limit of normal (ULN), >3×ULN and >5×ULN were detected in 543 (54.6%), 337 (33.9%) and 245 (24.6%) respectively. In the multivariate model, higher HbA1c levels were associated with less risk of postprocedural cTnI >1×ULN (odds ratio [OR], 0.85; 95% confidence interval [CI], 0.76–0.95; P = 0.005). There was a trend that higher HbA1c levels were associated with less risk of postprocedural cTnI >3×ULN (OR, 0.90; 95% CI, 0.81–1.02; P = 0.088). HbA1c was not associated with the risk of postprocedural cTnI elevation above 5×ULN (OR, 0.95; 95% CI, 0.84–1.08; P = 0.411).

Conclusions

The present study provided the first line of evidence that higher preprocedural HbA1c levels were associated with less risk of myocardial injury following elective PCI in diabetic patients.     

Impact of ECG Findings and Process-Of-Care Characteristics on the Likelihood of Not Receiving Reperfusion Therapy in Patients with ST-Elevation Myocardial Infarction: Results of a Field Evaluation

Background

Many patients with ST-elevation myocardial infarction (STEMI) do not receive reperfusion therapy and are known to have poorer outcomes. We aimed to perform the first population-level, integrated analysis of clinical, ECG and hospital characteristics associated with non-receipt of reperfusion therapy in patients with STEMI.

Methods and Results

This systematic evaluation of STEMI care in 82 hospitals in Quebec included all patients with a discharge diagnosis of myocardial infarction, presenting with characteristic symptoms and an ECG showing STEMI as attested by at least one of two study cardiologists or left bundle branch block (LBBB). Excluding LBBB, an ECG was considered a definite STEMI diagnosis if both cardiologists scored ‘certain STEMI’ and ambiguous if one scored ‘uncertain’ or ‘not STEMI’. Centers were classified according to accessibility to primary percutaneous coronary intervention (PPCI): 1) on-site PPCI; 2) routine transfer for PPCI; 3) varying mix of PPCI transfer and on-site fibrinolysis; and 4) routine on-site fibrinolysis. Of 3730 STEMI/LBBB patients, 812 (21.8%) did not receive reperfusion therapy. In multivariate analysis, likelihood of no reperfusion therapy was a function of PPCI accessibility (odds ratio [OR] for fibrinolysis versus PPCI centers = 3.1; 95% CI: 2.2–4.4), presence of LBBB (OR = 24.1; 95% CI: 17.8–32.9) and an ECG ambiguous for STEMI (OR = 4.1; 95% CI: 3.3–5.1). When the ECG was ambiguous, likelihood of no reperfusion therapy was highest in hospitals most distant from PPCI centers.

Conclusions

ECG diagnostic ambiguity, LBBB and PPCI accessibility are important predictors of not receiving reperfusion therapy, suggesting opportunities for improving outcomes.     

Efficacy and Safety of Biodegradable Polymer Biolimus-Eluting Stents versus Durable Polymer Drug-Eluting Stents: A Meta-Analysis

Backgrounds

Drug-eluting stents (DES) with biodegradable polymers have been developed to address the risk of thrombosis associated with first-generation DES. We aimed to determine the efficacy and safety of biodegradable polymer biolimus-eluting stents (BES) versus durable polymer DES.

Methods

Systematic database searches of MEDLINE (1950 to June 2013), EMBASE (1966 to June 2013), the Cochrane Central Register of Controlled Trials (Issue 6 of 12, June 2013), and a review of related literature were conducted. All randomized controlled trials comparing biodegradable polymer BES versus durable polymer DES were included.

Results

Eight randomized controlled trials investigating 11,015 patients undergoing percutaneous coronary interventions were included in the meta-analysis. The risk of major adverse cardiac events did not differ significantly between the patients treated with the biodegradable polymer BES and the durable polymer DES (Relative risk [RR], 0.970; 95% CI, 0.848–1.111; p = 0.662). However, biodegradable polymer BES was associated with reduced risk of very late ST compared with the durable polymer DES, while the risk of early or late ST was similar (RR for early or late ST, 1.167; 95% CI 0.755–1.802; p = 0.487; RR 0.273; 95% CI 0.115–0.652; p = 0.003; p for interaction = 0.003).

Conclusions

In this meta-analysis of randomized controlled trials, treatments with biodegradable polymer BES did not significantly reduce the risk of major adverse cardiac events, but demonstrated a significantly lower risk of very late ST when compared to durable polymer DES. This conclusion requires confirmation by further studies with long-term follow-up.

PROSPERO register number

http://www.crd.york.ac.uk/PROSPERO/display_record.asp?ID=CRD42013004364#.UnM2lfmsj6J     

Drug-eluting stents in patients with chronic kidney disease: a prospective registry study

Background

Chronic kidney disease (CKD) is strongly associated with adverse outcomes after percutaneous coronary intervention (PCI). There are limited data on the effectiveness of drug-eluting stents (DES) in patients with CKD.

Methodology/Principal Findings

Of 3,752 consecutive patients enrolled in the Guthrie PCI Registry between 2001 and 2006, 436 patients with CKD - defined as a creatinine clearance <60 mL/min - were included in this study. Patients who received DES were compared to those who received bare metal stents (BMS). Patients were followed for a mean duration of 3 years after the index PCI to determine the prognostic impact of stent type. Study end-points were all-cause death, myocardial infarction (MI), target vessel revascularization (TVR), stent thrombosis (ST) and the composite of major adverse cardiovascular events (MACE), defined as death, MI or TVR. Patients receiving DES in our study, by virtue of physician selection, had more stable coronary artery disease and had lower baseline risk of thrombotic or restenotic events. Kaplan-Meier estimates of proportions of patients reaching the end-points were significantly lower for DES vs. BMS for all-cause death (p = 0.0008), TVR (p = 0.029) and MACE (p = 0.0015), but not MI (p = 0.945) or ST (p = 0.88). Multivariable analysis with propensity adjustment demonstrated that DES implantation was an independent predictor of lower rates of all-cause death (hazard ratio [HR] 0.48, 95% confidence interval [CI] 0.25–0.92), TVR (HR 0.50, 95% CI 0.27–0.94) and MACE (HR 0.62, 95% CI 0.41–0.94).

Conclusions

In a contemporary PCI registry, selective use of DES in patients with CKD was safe and effective in the long term, with lower risk of all-cause death, TVR and MACE and similar risk of MI and ST as compared with BMS. The mortality benefit may be a result of selection bias and residual confounding, or represent a true finding; a hypothesis that warrants clarification by randomized clinical trials.     

Association of Localized Hypersensitivity and In-Stent Neoatherosclerosis with the Very Late Drug-Eluting Stent Thrombosis

Background

Localized hypersensitivity reaction, delayed arterial healing, and neoatherosclerosis inside the stent have been suggested as the underlying pathologic mechanisms of very late stent thrombosis (VLST) of drug-eluting stent (DES). The present study sought to explore the prevalence of inflammatory cell infiltrates and evidence for fragments of atherosclerotic plaques in the aspirated thrombi in patients with DES VLST.

Methods and Results

From April 2004 to September 2012, 48 patients with stent thrombosis (ST) of DES underwent thrombus aspiration with retrieved material sufficient for the histopathologic analysis; early ST (EST, within 30 days): N = 17, late ST (LST, between 31 and 365 days): N = 7, and very late ST (VLST, >1 year): N = 24. Eosinophil fraction in the aspirated thrombi was significantly higher in patients with VLST (8.2±5.7%) as compared with those with EST (4.3±3.0%) and LST (5.5±3.8%) (P = 0.03). Eosinophil fraction in the aspirated thrombi was significantly higher in 12 VLST patients with angiographic peri-stent contrast staining (PSS) and/or incomplete stent apposition (ISA) by intravascular ultrasound than in 12 VLST patients without PSS or ISA (10.6±6.1% versus 5.8±4.1%, P = 0.03). Evidences for fragments of atherosclerotic plaques in the aspirated thrombi were observed only in 3 (13%) out of 24 patients with DES VLST.

Conclusions

Eosinophil fraction in the aspirated thrombi was significantly higher in patients with DES VLST as compared with those with EST and LST. Evidences for fragments of atherosclerotic plaques were relatively uncommon in patients with DES VLST.     

Comparison of the Efficacy of Rosuvastatin versus Atorvastatin in Preventing Contrast Induced Nephropathy in Patient with Chronic Kidney Disease Undergoing Percutaneous Coronary Intervention

Objectives

We prospectively compared the preventive effects of rosuvastatin and atorvastatin on contrast-induced nephropathy (CIN) in patients with chronic kidney disease (CKD) undergoing percutaneous coronary intervention (PCI).

Methods

We enrolled 1078 consecutive patients with CKD undergoing elective PCI. Patients in Group 1 (n = 273) received rosuvastatin (10 mg), and those in group 2 (n = 805) received atorvastatin (20 mg). The primary end-point was the development of CIN, defined as an absolute increase in serum creatinine ≥0.5 mg/dL, or an increase ≥25% from baseline within 48–72 h after contrast medium exposure.

Results

CIN was observed in 58 (5.4%) patients. The incidence of CIN was similar in patients pretreated with either rosuvastatin or atorvastatin (5.9% vs. 5.2%, p = 0.684). The same results were also observed when using other definitions of CIN. Clinical and procedural characteristics did not show significant differences between the two groups (p>0.05). Additionally, there were no significant inter-group differences with respect to in-hospital mortality rates (0.4% vs. 1.5%, p = 0.141), or other in-hospital complications. Multivariate logistic regression analysis revealed that rosuvastatin and atorvastatin demonstrated similar efficacies for preventing CIN, after adjusting for potential confounding risk factors (odds ratio = 1.17, 95% confidence interval, 0.62–2.20, p = 0.623). A Kaplan–Meier survival analysis showed that patients taking either rosuvastatin or atorvastatin had similar incidences of all-cause mortality (9.4% vs. 7.1%, respectively; p = 0.290) and major adverse cardiovascular events (29.32% vs. 23.14%, respectively; p = 0.135) during follow-up.

Conclusions

Rosuvastatin and atorvastatin have similar efficacies for preventing CIN in patients with CKD undergoing PCI.     

Nanoporous CREG-Eluting Stent Attenuates In-Stent Neointimal Formation in Porcine Coronary Arteries

Background

The goal of this study was to evaluate the efficacy of a nanoporous CREG-eluting stent (CREGES) in inhibiting neointimal formation in a porcine coronary model.

Methods

In vitro proliferation assays were performed using isolated human endothelial and smooth muscle cells to investigate the cell-specific pharmacokinetic effects of CREG and sirolimus. We implanted CREGES, control sirolimus-eluting stents (SES) or bare metal stents (BMS) into pig coronary arteries. Histology and immunohistochemistry were performed to assess the efficacy of CREGES in inhibiting neointimal formation.

Results

CREG and sirolimus inhibited in vitro vascular smooth muscle cell proliferation to a similar degree. Interestingly, human endothelial cell proliferation was only significantly inhibited by sirolimus and was increased by CREG. CREGES attenuated neointimal formation after 4 weeks in porcine coronary model compared with BMS. No differences were found in the injury and inflammation scores among the groups. Scanning electron microscopy and CD31 staining by immunohistochemistry demonstrated an accelerated reendothelialization in the CREGES group compared with the SES or BMS control groups.

Conclusions

The current study suggests that CREGES reduces neointimal formation, promotes reendothelialization in porcine coronary stent model.