Bivalirudin with a post-procedure infusion versus heparin monotherapy for the prevention of stent thrombosis.

OBJECTIVES: To evaluate the efficacy of post-primary percutaneous coronary intervention (PCI) bivalirudin infusion (at full PCI dose) to prevent stent thrombosis (ST) compared with heparin monotherapy. BACKGROUND: Early randomized controlled trials (RCTs) have shown that compared with heparin use, bivalirudin use during primary PCI is associated with an increased risk of ST. However, bivalirudin was stopped in those trials at the end of the procedure and glycoprotein IIb/IIIa inhibitors (GPIs) were routinely used with heparin. The increased risk of ST may be eliminated by continuing bivalirudin infusion post-procedure for few hours. Indeed, in most recent trials, a trend of lower ST risk has been observed with a post-procedure infusion of bivalirudin compared with heparin monotherapy (without the routine use of GPI). METHODS: Relevant RCTs were included and risk ratios (RRs) were calculated using random effect models. The primary outcome of interest was the risk of early definite ST. RESULTS: Four RCTs involving 13,505 patients were included in this meta-analysis. Compared with heparin monotherapy, bivalirudin (with a post-procedure infusion) was associated with a 55% decrease in the risk of early definite ST (RR: 0.45, 95% confidence interval: 0.23-0.85; P = 0.015). There was no difference in the risk of early ST between bivalirudin (with a post-procedure infusion) and heparin with GPI. CONCLUSIONS: For primary PCI, a bivalirudin-based anticoagulant strategy (with post procedure infusion) is associated with a lower risk of early definite ST compared with treatment with heparin monotherapy (without GPI).

A comprehensive meta-analysis of randomized controlled trials comparing drug-eluting stents with bare-metal stents in saphenous vein graft interventions.

BACKGROUND: Several large randomized controlled trials (RCTs) have proven the superiority of drug-eluting stents (DESs) over bare-metal stents (BMSs) for native coronary stenosis. However, RCTs comparing DESs with BMSs for SVG lesions have predominantly been small in size and have yielded conflicting results. Therefore, we conducted an updated comprehensive meta-analysis of RCTs comparing DESs versus BMSs for SVG interventions using the largest sample size to date. METHODS: Scientific databases and websites were searched to find RCTs. Data from six RCTs involving 1,582 patients were included. Pooled risk ratios (RRs) were calculated using random-effects models. The primary outcome of this meta-analysis was target vessel revascularization (TVR). The secondary outcomes were major adverse cardiac events (MACEs), myocardial infarction (MI), stent thrombosis, all-cause mortality, and cardiac mortality. RESULTS: Data from six RCTs involving 1,582 patients were included. Saphenous vein graft interventions with DESs reduced TVR (RR, 0.52; 95% CI, 0.30-0.88; P = 0.017) and MACE rate (RR, 0.60; 95% CI, 0.42-0.87; P = 0.007) compared to BMSs. No difference between the stents were found in rates of MI (RR, 0.69; 95% CI, 0.43-1.10; P = 0.123), stent thrombosis (RR, 0.61; 95% CI, 0.27-1.41; P = 0.255), all-cause mortality (RR, 1.13; 95% CI, 0.74-1.71; P = 0.554), or cardiac mortality. CONCLUSION: For SVG intervention, the MACE rate was lower for DESs compared to BMSs, driven primarily by decreased non-MI-related TVR. Rates of MI, all-cause mortality, cardiac mortality, and stent thrombosis were not different between the stents.

Short-term versus long-term triple antithrombotic therapy for patients with coronary stents and requiring oral anticoagulation: a meta-analysis of randomized clinical trials.

BACKGROUND: The cornerstone therapy for patients with coronary stents is dual antiplatelet therapy (DAPT). In 5-10% of these patients, oral anticoagulation (OAC) is clearly indicated in addition to DAPT. However, the optimal duration of this triple antithrombotic therapy (TAT) remains uncertain. PATIENTS AND METHODS: Scientific databases and websites were searched for randomized clinical trials (RCTs). RCTs were included if patients undergoing coronary stent placements with additional indications of chronic OAC were randomly assigned to either short-term TAT or long-term TAT. Short-term TAT was defined as no more than 6 weeks of TAT, and long-term TAT was defined as 6-12 months of TAT RESULTS: Using data from three RCTs and 1883 patients, short-term TAT was associated with decreased rates of major adverse cardiovascular events, cardiac mortality, all-cause mortality, and any-bleeding events compared to long-term TAT, but similar rates of myocardial infarction, stroke, stent thrombosis, and thrombolysis in myocardial infarction major bleeding. Furthermore, in subgroup analysis, short-term TAT was associated with decreased rates of major adverse cardiovascular events, cardiac mortality, all-cause mortality, and any-bleeding compared to 12-month TAT, but similar rates compared to 6-month TAT. CONCLUSION: In patients who require chronic OAC therapy and undergo coronary stent placement, short-term TAT was associated with better efficacy and safety outcomes compared to long-term TAT.

A Meta-Analysis of Aspirin for the Primary Prevention of Cardiovascular Diseases in the Context of Contemporary Preventive Strategies.

BACKGROUND: The role of aspirin for primary prevention of cardiovascular diseases remains controversial, particularly in the context of contemporary aggressive preventive strategies. METHODS: Relevant randomized clinical trials were included, and risk ratios (RRs) were calculated using random-effects models. Additional moderator analyses were performed to compare the pooled treatment effects from recent trials (those reported after the guidelines of the National Cholesterol Education Program Third Adult Treatment Panel were published in 2001; thus, conducted on the background of contemporary preventive strategies) to the results of older trials. RESULTS: Data from 14 randomized controlled trials involving 164,751 patients were included. Aspirin use decreased myocardial infarction risk by 16% compared with placebo (RR 0.84; 95% confidence interval [CI], 0.75-0.94); however, in the moderator analyses, aspirin was not associated with a decreased risk of myocardial infarction in recent trials, but was in older trials (P-interaction = .02). Overall, aspirin use significantly increased the occurrence of major bleeding (RR 1.49; 95% CI, 1.32-1.69) and hemorrhagic stroke (RR 1.25; 95% CI, 1.01-1.54). In moderator analyses, the risk of major bleeding (P-interaction = .12) or hemorrhagic stroke (P-interaction = .44) with aspirin was not significantly different between the older and new trials. Differences between aspirin and placebo in the risks for all-cause stroke, cardiac death, and all-cause mortality were not found. CONCLUSIONS: In the context of contemporary primary prevention guidelines, the effect of aspirin on myocardial infarction risk was significantly attenuated, whereas its major bleeding and hemorrhagic stroke complications were retained. Therefore, in contemporary practice, routine use of aspirin for the primary prevention of cardiovascular events may have a net harmful effect.

Efficacy and Safety of Drug-Eluting Stents Optimized for Biocompatibility vs Bare-Metal Stents With a Single Month of Dual Antiplatelet Therapy: A Meta-analysis.

Importance: A significant number of patients receive bare-metal stents (BMSs) instead of drug-eluting stents (DESs) to shorten the duration of dual antiplatelet therapy (DAPT). Emerging evidence suggests that new-generation DESs, particularly those optimized for biocompatibility, may be more efficacious and safer than BMSs, even with a single month of DAPT after stent implantation. Objective: To evaluate the efficacy and safety of DESs compared with BMSs for coronary intervention with a single month of DAPT. Data Sources: Human studies found in PubMed, the Cochrane databases through April 2018, and reference lists of selected articles. Study Selection: Randomized clinical trials were included if they enrolled patients undergoing percutaneous coronary intervention and randomly assigned each patient to treatment with either DESs or BMSs. The additional inclusion criterion was use of only 1 month of DAPT poststent implantation. Data Extraction and Synthesis: Two reviewers independently extracted the data. Odds ratios (ORs) were calculated using random-effects models. Main Outcomes and Measures: The efficacy end points were major adverse cardiac events, myocardial infarction, target vessel revascularization, ischemia-driven target lesion revascularization, cardiac mortality, and all-cause mortality at 1 year. The safety outcomes were stent thrombosis and bleeding complications. Results: Data from 3 randomized clinical trials involving 3943 patients were included (2457 men [62.3%]; mean [SD] age ranging from 75.7 [9.3] years to 81.4 [4.3] years per trial subgroup). Coronary intervention with DESs reduced the rates for major adverse cardiac events (OR, 0.68 [95% CI, 0.57-0.82]; P < .001), target lesion revascularization (OR, 0.38 [95% CI, 0.22-0.67]; P = .001), target vessel revascularization (OR, 0.50 [95% CI, 0.38-0.65]; P < .001), and myocardial infarction (OR, 0.51 [95% CI, 0.31-0.83]; P = .01) compared with BMSs at 1 year. The incidence of stent thrombosis was also lower with DESs compared with BMSs (1.8% vs 2.8%), but this difference was not statistically significant in the random-effects model. Additionally, the 2 stent types did not differ in the risks of all-cause mortality, cardiac mortality, and bleeding. Conclusions and Relevance: In the limited number of randomized clinical trials comparing DESs with BMSs with shortened DAPT durations in patients who have high bleeding risk or are uncertain candidates for prolonged DAPT, coronary intervention with specific DESs optimized for biocompatibility is not only safe but also efficacious, even with only 1 month of DAPT.

A comprehensive meta-analysis of stem cell therapy for chronic angina.

BACKGROUND: A substantial proportion of patients with coronary artery disease do not achieve complete revascularization and continue to experience refractory angina despite optimal medical therapy. Recently, stem cell therapy has emerged as a potential therapeutic option for these patients. However, findings of individual trials have been scrutinized because of their small sample sizes and lack of statistical power. Therefore, we conducted an updated comprehensive meta-analysis of available randomized controlled trials (RCTs) with the largest sample size ever reported on this subject. HYPOTHESIS: In patients with chronic angina stem cell therapy improves clinical outcomes. METHODS: Scientific databases and websites were searched for RCTs. Data were independently collected by 2 investigators, and disagreements were resolved by consensus. Data from 10 trials including 658 patients were analyzed. RESULTS: Stem cell therapy improved Canadian Cardiovascular Society angina class (risk ratio: 1.53, 95% CI: 1.09 to 2.15, P = 0.013), exercise capacity (standardized mean difference [SMD]: 0.56, 95% CI: 0.23 to 0.88, P = 0.001), and left ventricular ejection fraction (SMD: 0.63, 95% CI: 0.27 to 1.00, P = 0.001) compared with placebo. It also decreased anginal episodes (SMD: -1.21, 95% CI: -2.40 to -0.02, P = 0.045) and myocardial perfusion defects (SMD: -0.70, 95% CI: -1.11 to -0.29, P = 0.001). However, no improvements in all-cause mortality were observed after a relatively short follow-up. CONCLUSIONS: In patients with chronic angina on optimal medical therapy, stem cell therapy improves symptoms, exercise capacity, and left ventricular ejection fraction. These findings warrant confirmation using larger trials.