Bora Toklu

Bare metal stents, durable polymer drug eluting stents, and biodegradable polymer drug eluting stents for coronary artery disease: mixed treatment comparison meta-analysis

Objective To compare the efficacy and safety of biodegradable polymer drug eluting stents with those of bare metal stents and durable polymer drug eluting stents. Design Mixed treatment comparison meta-analysis of 258 544 patient years of follow-up from randomized trials. Data sources and study selection PubMed, Embase, and Central were searched for randomized trials comparing any of the Food and Drug Administration approved durable polymer drug eluting stents (sirolimus eluting, paclitaxel eluting, cobalt chromium everolimus eluting, platinum chromium everolimus eluting, zotarolimus eluting-Endeavor, and zotarolimus eluting-Resolute) or biodegradable polymer drug eluting stents, with each other or against bare metal stents. Outcomes Long term efficacy (target vessel revascularization, target lesion revascularization) and safety (death, myocardial infarction, stent thrombosis). Landmark analysis at more than one year was evaluated to assess the potential late benefit of biodegradable polymer drug eluting stents. Results From 126 randomized trials and 258 544 patient years of follow-up, for long term efficacy (target vessel revascularization), biodegradable polymer drug eluting stents were superior to paclitaxel eluting stents (rate ratio 0.66, 95% credibility interval 0.57 to 0.78) and zotarolimus eluting stent-Endeavor (0.69, 0.56 to 0.84) but not to newer generation durable polymer drug eluting stents (for example: 1.03, 0.89 to 1.21 versus cobalt chromium everolimus eluting stents). Similarly, biodegradable polymer drug eluting stents were superior to paclitaxel eluting stents (rate ratio 0.61, 0.37 to 0.89) but inferior to cobalt chromium everolimus eluting stents (2.04, 1.27 to 3.35) for long term safety (definite stent thrombosis). In the landmark analysis after one year, biodegradable polymer drug eluting stents were superior to sirolimus eluting stents for definite stent thrombosis (rate ratio 0.29, 0.10 to 0.82) but were associated with increased mortality compared with cobalt chromium everolimus eluting stents (1.52, 1.02 to 2.22). Overall, among all stent types, the newer generation durable polymer drug eluting stents (zotarolimus eluting stent-Resolute, cobalt chromium everolimus eluting stents, and platinum chromium everolimus eluting stents) were the most efficacious (lowest target vessel revascularization rate) stents, and cobalt chromium everolimus eluting stents were the safest with significant reductions in definite stent thrombosis (rate ratio 0.35, 0.21 to 0.53), myocardial infarction (0.65, 0.55 to 0.75), and death (0.72, 0.58 to 0.90) compared with bare metal stents. Conclusions Biodegradable polymer drug eluting stents are superior to first generation durable polymer drug eluting stents but not to newer generation durable polymer stents in reducing target vessel revascularization. Newer generation durable polymer stents, and especially cobalt chromium everolimus eluting stents, have the best combination of efficacy and safety. The utility of biodegradable polymer stents in the context of excellent clinical outcomes with newer generation durable polymer stents needs to be proven.

Complete Versus Culprit-Only Revascularization for ST-Segment–Elevation Myocardial Infarction and Multivessel Disease A Meta-Analysis and Trial Sequential Analysis of Randomized Trials

Background—The 2013 American College of Cardiology Foundation/American Heart Association guidelines for patients with ST-segment–elevation myocardial infarction gives a class III indication for nonculprit artery percutaneous coronary intervention at the time of primary percutaneous coronary intervention, driven by data from observational studies. However, more recent trials suggest otherwise. Methods and Results—We conducted PUBMED, EMBASE, and CENTRAL searches for randomized trials comparing complete versus culprit-only revascularization in patients with ST-segment–elevation myocardial infarction. Efficacy outcomes were major adverse cardiovascular events, as well as death, cardiovascular death, myocardial infarction, and repeat revascularization. Safety outcomes were contrast-induced nephropathy, contrast volume used, and procedure time. Five trials with 1165 patients fulfilled the inclusion criteria. Complete revascularization (68% during index percutaneous coronary intervention) was associated with significant reduction in major adverse cardiovascular events (rate ratio =0.48; 95% confidence interval =0.37–0.61), death (rate ratio =0.60; 95% confidence interval =0.38–0.97), cardiovascular death (rate ratio =0.38, 95% confidence interval =0.20–0.73), and repeat revascularization (rate ratio =0.42; 95% confidence interval =0.31–0.57) when compared with culprit-only revascularization. However, trial sequential analyses (similar to interim analysis of a randomized trial) powered for a 25% relative reduction showed firm evidence (cumulative z-curve crossed the monitoring boundary) only for major adverse cardiovascular events driven by a decrease in repeat revascularization with no firm evidence for reduction in death and myocardial infarction. Moreover, there was a significant increase in contrast volume use (mean difference 85.12 [70.41–83.00] ml) and procedure time (mean difference 16.42 [13.22–19.63] mins) with complete revascularization without increase in contrast-induced nephropathy. Conclusions—In patients with ST-segment–elevation myocardial infarction, immediate or staged complete revascularization results in significant reduction in major adverse cardiovascular events driven largely by reduction in repeat revascularization with no firm evidence for the reduction in death or myocardial infarction when compared with culprit-only revascularization.

Outcomes With Coronary Artery Bypass Graft Surgery Versus Percutaneous Coronary Intervention for Patients With Diabetes Mellitus Can Newer Generation Drug-Eluting Stents Bridge the Gap?

Background—Coronary artery bypass graft surgery (CABG) compared with percutaneous coronary intervention (PCI) reduces mortality in patients with diabetes mellitus. However, prior trials compared CABG with balloon angioplasty or older generation stents, and it is not known if the gap between CABG and PCI can be reduced by newer generation drug-eluting stents. Methods and Results—PUBMED/EMBASE/CENTRAL search for randomized trials comparing mode of revascularization in patients with diabetes mellitus. Primary outcome was all-cause mortality. Secondary outcomes were myocardial infarction, repeat revascularization, and stroke. Mixed treatment comparison analyses were performed using a random-effects Poisson regression model. Sixty-eight randomized trials that enrolled 24 015 diabetic patients with a total of 71 595 patient-years of follow-up satisfied our inclusion criteria. When compared with CABG (reference rate ratio [RR]=1.0), PCI with paclitaxel-eluting stent (RR=1.57 [1.15–2.19]) or sirolimus-eluting stent (RR=1.43 [1.06–1.97]) was associated with an increase in mortality. However, PCI with cobalt–chromium everolimus-eluting stent (RR=1.11 [0.67–1.84]) was not associated with a statistically significant increase in mortality. When compared with CABG, there was excess repeat revascularization with PCI, which progressively declined from plain old balloon angioplasty (341% increase) to bare metal stent (218% increase) to paclitaxel-eluting stent (81% increase) and to sirolimus-eluting stent (47% increase). However, for PCI with cobalt–chromium everolimus-eluting stent (RR=1.31 [0.74–2.29]), the excess repeat revascularization was not statistically significant although the point estimate favored CABG. CABG was associated with numerically higher stroke. Conclusions—In patients with diabetes mellitus, evidence from indirect comparison shows similar mortality between CABG and PCI using cobalt–chromium everolimus-eluting stent. CABG was associated with numerically excess stroke and PCI with cobalt–chromium everolimus-eluting stent with numerically increased repeat revascularization. This hypothesis needs to be tested in future trials.

Diabetes mellitus as a compelling indication for use of renin angiotensin system blockers: systematic review and meta-analysis of randomized trials

Objective To evaluate the outcomes with use of renin angiotensin system (RAS) blockers compared with other antihypertensive agents in people with diabetes. Design Meta-analysis. Data sources and study selection PubMed, Embase, and the Cochrane central register of controlled trials databases for randomized trials of RAS blockers versus other antihypertensive agents in people with diabetes mellitus. Outcomes were death, cardiovascular death, myocardial infarction, angina, stroke, heart failure, revascularization, and end stage renal disease. Results The search yielded 19 randomized controlled trials that enrolled 25 414 participants with diabetes for a total of 95 910 patient years of follow-up. When compared with other antihypertensive agents, RAS blockers were associated with a similar risk of death (relative risk 0.99, 95% confidence interval 0.93 to 1.05), cardiovascular death (1.02, 0.83 to 1.24), myocardial infarction (0.87, 0.64 to 1.18), angina pectoris (0.80, 0.58 to 1.11), stroke (1.04, 0.92 to 1.17), heart failure (0.90, 0.76 to 1.07), and revascularization (0.97, 0.77 to 1.22). There was also no difference in the hard renal outcome of end stage renal disease (0.99, 0.78 to 1.28) (power of 94% to show a 23% reduction in end stage renal disease). Conclusions In people with diabetes, RAS blockers are not superior to other antihypertensive drug classes such as thiazides, calcium channel blockers, and β blockers at reducing the risk of hard cardiovascular and renal endpoints. These findings support the recommendations of the guidelines of the European Society of Cardiology/European Society of Hypertension and eighth Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure to also use other antihypertensive agents in people with diabetes but without kidney disease.

Anticoagulant therapy during primary percutaneous coronary intervention for acute myocardial infarction: a meta-analysis of randomized trials in the era of stents and P2Y12 inhibitors

Objectives To investigate the relative benefits of unfractionated heparin, low molecular weight heparin(LMWH), fondaparinux, and bivalirudin as treatment options for patients with ST segment elevation myocardial infarction undergoing percutaneous coronary intervention (PCI). Design Mixed treatment comparison and direct comparison meta-analysis of randomized trials in the era of stents and P2Y12 inhibitors. Data sources and study selection A search of Medline, Embase, Cochrane Central Register of Controlled Trials (CENTRAL) for randomized trials comparing unfractionated heparin plus glycoprotein IIb/IIIa inhibitor(GpIIb/IIIa inhibitor), unfractionated heparin, bivalirudin, fondaparinux, or LMWH plus GpIIb/IIIa inhibitor for patients undergoing primary PCI. Outcomes The primary efficacy outcome was short term (in hospital or within 30 days) major adverse cardiovascular event; the primary safety outcome was short term major bleeding. Results We identified 22 randomized trials that enrolled 22 434 patients. In the mixed treatment comparison models, when compared with unfractionated heparin plus GpIIb/IIIa inhibitor, unfractionated heparin was associated with a higher risk of major adverse cardiovascular events (relative risk 1.49 (95% confidence interval 1.21 to 1.84), as were bivalirudin (relative risk 1.34 (1.01 to 1.78)) and fondaparinux (1.78 (1.01 to 3.14)). LMWH plus GpIIb/IIIa inhibitor showed highest treatment efficacy, followed (in order) by unfractionated heparin plus GpIIb/IIIa inhibitor, bivalirudin, unfractionated heparin, and fondaparinux. Bivalirudin was associated with lower major bleeding risk compared with unfractionated heparin plus GpIIb/IIIa inhibitor (relative risk 0.47 (0.30 to 0.74)) or unfractionated heparin (0.58 (0.37 to 0.90)). Bivalirudin, followed by unfractionated heparin, LMWH plus GpIIb/IIIa inhibitor, unfractionated heparin plus GpIIb/IIIa inhibitor, and fondaparinux were the hierarchy for treatment safety. Results were similar in direct comparison meta-analyses: bivalirudin was associated with a 39%, 44%, and 65% higher risk of myocardial infarction, urgent revascularization, and stent thrombosis respectively when compared with unfractionated heparin with or without GpIIb/IIIa inhibitor. However, bivalirudin was associated with a 48% lower risk of major bleeding compared with unfractionated heparin plus GpIIb/IIIa inhibitor and 32% lower compared with unfractionated heparin alone. Conclusions In patients undergoing primary PCI, unfractionated heparin plus GpIIb/IIIa inhibitor and LMWH plus GpIIb/IIIa inhibitor were most efficacious, with the lowest rate of major adverse cardiovascular events, whereas bivalirudin was safest, with the lowest bleeding. These relationships should be considered in selecting anticoagulant therapies in patients undergoing primary PCI.

Angiotensin-Converting Enzyme Inhibitors or Angiotensin Receptor Blockers in Patients Without Heart Failure? Insights From 254,301 Patients From Randomized Trials

OBJECTIVES To compare the efficacy and safety of angiotensin-converting enzyme inhibitors (ACEis) and angiotensin receptor blockers (ARBs) in patients without heart failure. PATIENTS AND METHODS Meta-analysis of randomized trials identified using PubMed, Embase, and Cochrane Central Register of Controlled Trials searches from January 1, 1980, through April 13, 2015, of ACEis and ARBs compared with placebo or active controls and corroborated with head-to-head trials of ARBs vs ACEis. Outcomes were all-cause mortality, cardiovascular death, myocardial infarction (MI), angina, stroke, heart failure, revascularization, and new-onset diabetes. RESULTS Our search yielded 106 randomized trials that enrolled 254,301 patients. Compared with placebo, ACEis but not ARBs reduced the outcomes of all-cause mortality (ACEis vs placebo: relative risk [RR], 0.89; 95% CI, 0.80-1.00; ARBs vs placebo: RR, 1.01; 95% CI, 0.96-1.06; Pinteraction=.04), cardiovascular death (RR, 0.83; 95% CI, 0.70-0.99 and RR, 1.02; 95% CI, 0.92-1.14; Pinteraction=.05), and MI (RR, 0.83; 95% CI, 0.78-0.90 and RR, 0.93; 95% CI, 0.85-1.03; Pinteraction=.06). The meta-regression analysis revealed that the difference between ACEis and ARBs compared with placebo was due to a higher placebo event rate in the ACEis trials (most of these trials were conducted a decade earlier than the ARB trials) for the outcome of all-cause mortality (P=.001), cardiovascular death (P<.001), and MI (P=.02). Sensitivity analyses restricted to trials published after 2000 revealed similar outcomes with ACEis vs placebo and ARBs vs placebo (Pinteraction>.05). Head-to-head comparison trials of ARBs vs ACEis exhibited no difference in outcomes except for a lower risk of drug withdrawal due to adverse effects with ARBs (RR, 0.72; 95% CI, 0.65-0.81). CONCLUSION In patients without heart failure, evidence from placebo-controlled trials (restricted to trials after 2000), active controlled trials, and head-to-head randomized trials all suggest ARBs to be as efficacious and safe as ACEis, with the added advantage of better tolerability.

Efficacy of cilostazol on platelet reactivity and cardiovascular outcomes in patients undergoing percutaneous coronary intervention: insights from a meta-analysis of randomised trials

Background Cilostazol overcomes high on-treatment platelet reactivity (HTPR) and reduces adverse cardiovascular (CV) outcomes after percutaneous coronary intervention (PCI). However, the role for triple antiplatelet therapy (TAPT) with cilostazol in addition to aspirin and clopidogrel after PCI is not well defined. Methods We conducted a MEDLINE/EMBASE/CENTRAL search for randomised trials, until May 2014, evaluating TAPT compared with dual antiplatelet therapy (DAPT) of aspirin and clopidogrel alone in patients undergoing PCI and reporting platelet reactivity and/or CV outcomes. The primary platelet reactivity outcome was differences in platelet reactivity unit (PRU) with secondary outcomes of %platelet inhibition and rate of HTPR. The primary CV outcome was major adverse cardiovascular events (MACE), with secondary outcomes of death, cardiovascular death, myocardial infarction, stent thrombosis (ST), target lesion revascularisation (TLR) and target vessel revascularisation (TVR) as well as safety outcomes of bleeding and drug discontinuations. Results In 17 trials that evaluated platelet reactivity outcomes, the mean PRU value was 47.73 units lower with TAPT versus DAPT (95% CI −61.41 to −34.04, p<0.0001; mean PRU 182.90 vs 232.65). TAPT also increased platelet inhibition by 12.71% (95% CI 10.76 to 14.67, p<0.0001), and led to a 60% reduction in the risk of HTPR (relative risk=0.40; 95% CI 0.30 to 0.53) compared with DAPT. Moreover, among the 34 trials that evaluated CV outcomes, TAPT reduced the risk of MACE (incident rate ratio (IRR)=0.68; 95% CI 0.60 to 0.78), TLR (IRR=0.57; 95% CI 0.44 to 0.73), TVR (IRR=0.69; 95% CI 0.59 to 0.81) and ST (IRR=0.63; 95% CI 0.40 to 0.98) with no difference for other outcomes including bleeding, even in trials using drug-eluting stents. Drug discontinuation due to adverse effects was, however, higher with TAPT vs DAPT (IRR=1.59; 95% CI 1.32 to 1.91). Conclusions In patients undergoing PCI, addition of cilostazol to DAPT results in decreased platelet reactivity and a significant reduction in CV outcomes including ST, even in the drug-eluting stent era.

Renin angiotensin system inhibitors for patients with stable coronary artery disease without heart failure: systematic review and meta-analysis of randomized trials

Objective To critically evaluate the efficacy of renin angiotensin system inhibitors (RASi) in patients with coronary artery disease without heart failure, compared with active controls or placebo. Design Meta-analysis of randomized trials. Data sources PubMed, EMBASE, and CENTRAL databases until 1 May 2016. Eligibility criteria for selecting studies Randomized trials of RASi versus placebo or active controls in patients with stable coronary artery disease without heart failure (defined as left ventricular ejection fraction ≥40% or without clinical heart failure). Each trial had to enroll at least 100 patients with coronary artery disease without heart failure, with at least one year’s follow-up. Studies were excluded if they were redacted or compared use of angiotensin converting enzyme inhibitors with angiotensin receptor blockers. Outcomes were death, cardiovascular death, myocardial infarction, angina, stroke, heart failure, revascularization, incident diabetes, and drug withdrawal due to adverse effects. Results 24 trials with 198 275 patient years of follow-up were included. RASi reduced the risk of all cause mortality (rate ratio 0.84, 95% confidence interval 0.72 to 0.98), cardiovascular mortality (0.74, 0.59 to 0.94), myocardial infarction (0.82, 0.76 to 0.88), stroke (0.79, 0.70 to 0.89), angina, heart failure, and revascularization when compared with placebo but not when compared with active controls (all cause mortality, 1.05, 0.94 to 1.17; Pinteraction=0.006; cardiovascular mortality, 1.08, 0.93 to 1.25, Pinteraction<0.001; myocardial infarction, 0.99, 0.87 to 1.12, Pinteraction=0.01; stroke, 1.10, 0.93 to 1.31; Pinteraction=0.002). Bayesian meta-regression analysis showed that the effect of RASi when compared with placebo on all cause mortality and cardiovascular mortality was dependent on the control event rate, such that RASi was only beneficial in trials with high control event rates (>14.10 deaths and >7.65 cardiovascular deaths per 1000 patient years) but not in those with low control event rates. Conclusions In patients with stable coronary artery disease without heart failure, RASi reduced cardiovascular events and death only when compared with placebo but not when compared with active controls. Even among placebo controlled trials in this study, the benefit of RASi was mainly seen in trials with higher control event rates but not in those with lower control event rates. Evidence does not support a preferred status of RASi over other active controls.

Outcomes with bioabsorbable vascular scaffolds versus everolimus eluting stents: Insights from randomized trials.

BACKGROUND Bioresorbable vascular scaffolds (BVS) have been shown to be non-inferior to second generation drug eluting stents in recent clinical trials. However, the trials were not powered for individual endpoints and there is concern for increased device thrombosis with BVS. METHODS We performed a systematic search for randomized clinical trials of BVS versus EES. Efficacy outcomes were target lesion revascularization (TLR) and target vessel revascularization (TVR). Safety outcomes were death, myocardial infarction (MI), and device thrombosis. Meta-regression analyses were performed to evaluate the association of device thrombosis with clinical characteristics (percent patients with acute coronary syndrome) and device deployment characteristics (percent with post stent balloon dilation). RESULTS We identified six RCTs that enrolled 3738 patients. When compared with EES, BVS was associated with similar risk of TLR (RR=1.06; 95% CI 0.73-1.54), TVR (RR=1.00; 95% CI 0.74-1.35), death (RR=1.11; 95% CI 0.53-2.33) and cardiovascular death (RR=1.39; 95% CI 0.43-4.43) but numerically higher MI (RR=1.35; 95% CI 0.98-1.86) and definite or probable device thrombosis (RR=2.11; 95% CI 0.99-4.47). In a sensitivity analysis using the Peto odds ratio method, the risk of definite or probable device thrombosis was significantly increased (OR=2.08; 95% CI 1.06-4.08; P=0.03), although this did not reach statistical significance in four other models. The risk of definite or probable device thrombosis with BVS was reduced in trials where more post stent balloon dilation was used and in patients without acute coronary syndrome. Moreover, trial sequential analysis showed that the cumulative z-curve crossed the conventional boundary and not the trial sequential boundary, indicating lack of robust data to support increased definite or probable device thrombosis with BVS. CONCLUSIONS In patients with noncomplex obstructive coronary disease, BVS are comparable to EES for most efficacy and safety outcomes except for a numerical increase in device thrombosis and MI. The risk of the latter outcomes was mitigated in trials where more post stent balloon dilation was used and in patients without acute coronary syndrome. Moreover, with only 3738 patients, the trials are underpowered to detect a difference in rare events such as device thrombosis.

Newer Generation Ultra-Thin Strut Drug-Eluting Stents versus Older Second-Generation Thicker Strut Drug-Eluting Stents for Coronary Artery Disease: A Meta-Analysis of Randomized Trials

Background: Contemporary second-generation drug-eluting stents (DES) have superior efficacy and safety in comparison with early-generation stents in patients undergoing percutaneous coronary intervention, in part, related to their thinner struts. Whether newer-generation ultrathin DES further improve clinical outcomes in comparison with older second-generation thicker strut DES is unknown. Methods: We searched PubMed, Embase, and Cochrane Central Register of Controlled Trials for randomized clinical trials that compared newer-generation ultrathin strut DES (defined as strut thickness <70 µm) versus thicker strut second-generation DES and reported clinical outcomes. The primary outcome was target lesion failure (composite of cardiovascular death, target vessel myocardial infarction or ischemia-driven target lesion revascularization) evaluated at 1-year follow-up. Tests for subgroup effects based on the ultrathin strut DES type and the comparator DES type were performed by using meta-regression analysis. Results: We identified 10 trials that randomly assigned 11 658 patients and evaluated 3 newer-generation ultrathin strut DES: Orsiro stent (60 &mgr;m), MiStent (64 &mgr;m), and BioMime (65 µm). In comparison with thicker strut second-generation DES, newer-generation ultrathin strut DES were associated with a 16% reduction in target lesion failure (relative risk, 0.84; 95% CI, 0.72–0.99) driven by less myocardial infarction (relative risk, 0.80; 95% CI, 0.65–0.99). Ultrathin strut DES were also associated with qualitatively lower rates of any stent thrombosis (relative risk, 0.72; 95% CI, 0.51–1.01). Tests for subgroup effects based on the ultrathin strut DES type (P=0.58) and the comparator DES type (P=0.98) were not significant, suggesting consistent outcomes across the 3 ultrathin strut DES and with the different DES comparators. Conclusions: In patients undergoing percutaneous coronary intervention, newer-generation ultrathin strut DES further improve 1-year clinical outcomes in comparison with contemporary thicker strut second-generation DES.