Dik Heg

Radial versus femoral access in patients with acute coronary syndromes undergoing invasive management: a randomised multicentre trial

BACKGROUND It is unclear whether radial compared with femoral access improves outcomes in unselected patients with acute coronary syndromes undergoing invasive management. METHODS We did a randomised, multicentre, superiority trial comparing transradial against transfemoral access in patients with acute coronary syndrome with or without ST-segment elevation myocardial infarction who were about to undergo coronary angiography and percutaneous coronary intervention. Patients were randomly allocated (1:1) to radial or femoral access with a web-based system. The randomisation sequence was computer generated, blocked, and stratified by use of ticagrelor or prasugrel, type of acute coronary syndrome (ST-segment elevation myocardial infarction, troponin positive or negative, non-ST-segment elevation acute coronary syndrome), and anticipated use of immediate percutaneous coronary intervention. Outcome assessors were masked to treatment allocation. The 30-day coprimary outcomes were major adverse cardiovascular events, defined as death, myocardial infarction, or stroke, and net adverse clinical events, defined as major adverse cardiovascular events or Bleeding Academic Research Consortium (BARC) major bleeding unrelated to coronary artery bypass graft surgery. The analysis was by intention to treat. The two-sided α was prespecified at 0·025. The trial is registered at ClinicalTrials.gov, number NCT01433627. FINDINGS We randomly assigned 8404 patients with acute coronary syndrome, with or without ST-segment elevation, to radial (4197) or femoral (4207) access for coronary angiography and percutaneous coronary intervention. 369 (8·8%) patients with radial access had major adverse cardiovascular events, compared with 429 (10·3%) patients with femoral access (rate ratio [RR] 0·85, 95% CI 0·74-0·99; p=0·0307), non-significant at α of 0·025. 410 (9·8%) patients with radial access had net adverse clinical events compared with 486 (11·7%) patients with femoral access (0·83, 95% CI 0·73-0·96; p=0·0092). The difference was driven by BARC major bleeding unrelated to coronary artery bypass graft surgery (1·6% vs 2·3%, RR 0·67, 95% CI 0·49-0·92; p=0·013) and all-cause mortality (1·6% vs 2·2%, RR 0·72, 95% CI 0·53-0·99; p=0·045). INTERPRETATION In patients with acute coronary syndrome undergoing invasive management, radial as compared with femoral access reduces net adverse clinical events, through a reduction in major bleeding and all-cause mortality. FUNDING The Medicines Company and Terumo.

Long-term clinical outcomes of biodegradable polymer biolimus-eluting stents versus durable polymer sirolimus-eluting stents in patients with coronary artery disease (LEADERS): 4 year follow-up of a randomised non-inferiority trial.

BACKGROUND The effectiveness of durable polymer drug-eluting stents comes at the expense of delayed arterial healing and subsequent late adverse events such as stent thrombosis (ST). We report the 4 year follow-up of an assessment of biodegradable polymer-based drug-eluting stents, which aim to improve safety by avoiding the persistent inflammatory stimulus of durable polymers. METHODS We did a multicentre, assessor-masked, non-inferiority trial. Between Nov 27, 2006, and May 18, 2007, patients aged 18 years or older with coronary artery disease were randomly allocated with a computer-generated sequence to receive either biodegradable polymer biolimus-eluting stents (BES) or durable polymer sirolimus-eluting stents (SES; 1:1 ratio). The primary endpoint was a composite of cardiac death, myocardial infarction, or clinically-indicated target vessel revascularisation (TVR); patients were followed-up for 4 years. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00389220. FINDINGS 1707 patients with 2472 lesions were randomly allocated to receive either biodegradable polymer BES (857 patients, 1257 lesions) or durable polymer SES (850 patients, 1215 lesions). At 4 years, biodegradable polymer BES were non-inferior to durable polymer SES for the primary endpoint: 160 (18·7%) patients versus 192 (22·6%) patients (rate ratios [RR] 0·81, 95% CI 0·66-1·00, p for non-inferiority <0·0001, p for superiority=0·050). The RR of definite ST was 0·62 (0·35-1·08, p=0·09), which was largely attributable to a lower risk of very late definite ST between years 1 and 4 in the BES group than in the SES group (RR 0·20, 95% CI 0·06-0·67, p=0·004). Conversely, the RR of definite ST during the first year was 0·99 (0·51-1·95; p=0·98) and the test for interaction between RR of definite ST and time was positive (p(interaction)=0·017). We recorded an interaction with time for events associated with ST but not for other events. For primary endpoint events associated with ST, the RR was 0·86 (0·41-1·80) during the first year and 0·17 (0·04-0·78) during subsequent years (p(interaction)=0·049). INTERPRETATION Biodegradable polymer BES are non-inferior to durable polymer SES and, by reducing the risk of cardiac events associated with very late ST, might improve long-term clinical outcomes for up to 4 years compared with durable polymer SES. FUNDING Biosensors Europe SA, Switzerland.

Effect of biolimus-eluting stents with biodegradable polymer vs bare-metal stents on cardiovascular events among patients with acute myocardial infarction: the COMFORTABLE AMI randomized trial

CONTEXT The efficacy and safety of drug-eluting stents compared with bare-metal stents remains controversial in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI). OBJECTIVE To compare stents eluting biolimus from a biodegradable polymer with bare-metal stents in primary PCI. DESIGN, SETTING, AND PATIENTS A prospective, randomized, single-blinded, controlled trial of 1161 patients presenting with STEMI at 11 sites in Europe and Israel between September 19, 2009, and January 25, 2011. Clinical follow-up was performed at 1 and 12 months. INTERVENTION Patients were randomized 1:1 to receive the biolimus-eluting stent (n = 575) or the bare-metal stent (n = 582). MAIN OUTCOME MEASURES Primary end point was the rate of major adverse cardiac events, a composite of cardiac death, target vessel-related reinfarction, and ischemia-driven target-lesion revascularization at 1 year. RESULTS Major adverse cardiac events at 1 year occurred in 24 patients (4.3%) receiving biolimus-eluting stents with biodegradable polymer and 49 patients (8.7%) receiving bare-metal stents (hazard ratio [HR], 0.49; 95% CI, 0.30-0.80; P = .004). The difference was driven by a lower risk of target vessel-related reinfarction (3 [0.5%] vs 15 [2.7%]; HR, 0.20; 95% CI, 0.06-0.69; P = .01) and ischemia-driven target-lesion revascularization (9 [1.6%] vs 32 [5.7%]; HR, 0.28; 95% CI, 0.13-0.59; P < .001) in patients receiving biolimus-eluting stents compared with those receiving bare-metal stents. Rates of cardiac death were not significantly different (16 [2.9%] vs 20 [3.5%], P = .53). Definite stent thrombosis occurred in 5 patients (0.9%) treated with biolimus-eluting stents and 12 patients (2.1%; HR, 0.42; 95% CI, 0.15-1.19; P = .10) treated with bare-metal stents. CONCLUSION Compared with a bare-metal stent, the use of biolimus-eluting stents with a biodegradable polymer resulted in a lower rate of the composite of major adverse cardiac events at 1 year among patients with STEMI undergoing primary PCI. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00962416.

Bivalirudin or Unfractionated Heparin in Acute Coronary Syndromes

BACKGROUND Conflicting evidence exists on the efficacy and safety of bivalirudin administered as part of percutaneous coronary intervention (PCI) in patients with an acute coronary syndrome. METHODS We randomly assigned 7213 patients with an acute coronary syndrome for whom PCI was anticipated to receive either bivalirudin or unfractionated heparin. Patients in the bivalirudin group were subsequently randomly assigned to receive or not to receive a post-PCI bivalirudin infusion. Primary outcomes for the comparison between bivalirudin and heparin were the occurrence of major adverse cardiovascular events (a composite of death, myocardial infarction, or stroke) and net adverse clinical events (a composite of major bleeding or a major adverse cardiovascular event). The primary outcome for the comparison of a post-PCI bivalirudin infusion with no post-PCI infusion was a composite of urgent target-vessel revascularization, definite stent thrombosis, or net adverse clinical events. RESULTS The rate of major adverse cardiovascular events was not significantly lower with bivalirudin than with heparin (10.3% and 10.9%, respectively; relative risk, 0.94; 95% confidence interval [CI], 0.81 to 1.09; P=0.44), nor was the rate of net adverse clinical events (11.2% and 12.4%, respectively; relative risk, 0.89; 95% CI, 0.78 to 1.03; P=0.12). Post-PCI bivalirudin infusion, as compared with no infusion, did not significantly decrease the rate of urgent target-vessel revascularization, definite stent thrombosis, or net adverse clinical events (11.0% and 11.9%, respectively; relative risk, 0.91; 95% CI, 0.74 to 1.11; P=0.34). CONCLUSIONS In patients with an acute coronary syndrome, the rates of major adverse cardiovascular events and net adverse clinical events were not significantly lower with bivalirudin than with unfractionated heparin. The rate of the composite of urgent target-vessel revascularization, definite stent thrombosis, or net adverse clinical events was not significantly lower with a post-PCI bivalirudin infusion than with no post-PCI infusion. (Funded by the Medicines Company and Terumo Medical; MATRIX ClinicalTrials.gov number, NCT01433627.).

Impact of permanent pacemaker implantation on clinical outcome among patients undergoing transcatheter aortic valve implantation.

OBJECTIVES This study sought to assess the impact of permanent pacemaker (PPM) implantation on clinical outcomes among patients undergoing transfemoral transcatheter aortic valve implantation (TAVI). BACKGROUND TAVI is associated with atrioventricular-conduction abnormalities requiring PPM implantation in up to 40% among patients treated with self-expanding prostheses. METHODS Between 2007 and 2010, 353 consecutive patients (mean age: 82.6 ± 6.1 years, log EuroSCORE: 25.0 ± 15.0%) with severe aortic stenosis underwent transfemoral TAVI at 2 institutions. Clinical outcomes were compared among 3 groups: (1) patients requiring PPM implantation after TAVI (PPM after TAVI), (2) patients without PPM before or after TAVI (no PPM), and (3) patients with PPM before TAVI (PPM before TAVI). The primary endpoint was all-cause mortality at 12 months, and an age-, sex-, and origin-matched standardized population served as controls. RESULTS Of 353 patients, 98 patients (27.8%) belonged to the PPM after TAVI group, 48 patients (13.6%) belonged to the PPM before TAVI group, and 207 patients (58.6%) belonged to the no PPM group. The PPM before TAVI patients had a significantly higher baseline risk compared with the PPM after TAVI and no PPM patients (coronary artery disease: 77.1% vs. 52.7% and 58.2%, respectively, p = 0.009; atrial fibrillation: 43.8% vs. 22.7% and 20.4%, respectively, p = 0.005). At 12 months of follow-up, all-cause mortality was similar in all 3 groups (PPM after TAVI group: 19.4%, PPM before TAVI group: 22.9%, no PPM group: 18.0%) in unadjusted analyses (p = 0.77) and adjusted analyses (p = 0.90). Compared with the standardized population, adjusted hazard ratios for death were 2.37 (95% confidence interval [CI]: 1.51 to 3.72) for the PPM after TAVI group, 2.75 (95% CI: 1.52 to 4.97) for the PPM before TAVI group, and 2.24 (95% CI: 1.62 to 3.09) for the no PPM group. CONCLUSIONS Although prognosis remains impaired compared with an age-, sex-, and origin-matched standardized population, periprocedural PPM implantation does not seem to affect clinical outcomes adversely among patients undergoing transfemoral TAVI.

Predation risk is an ecological constraint for helper dispersal in a cooperatively breeding cichlid.

Environmental conditions are thought to be responsible for the extent and benefits of cooperative breeding in many animal societies, but experimental tests are scarce. We manipulated predator pressure in the cooperatively breeding cichlid Neolamprologus pulcher in Lake Tanganyika, where predators have been suggested to influence helper and breeder survival, helper dispersal and group reproductive success. We varied the type and intensity of predation by releasing medium, large, or no predators inside large underwater cages enclosing two or three group territories. Helper and breeder survival, helper dispersal and group reproductive success decreased from the control, to the medium– and large–predator treatments. These effects were modified by helper body size and the number of adults protecting the group from predators, supporting the ‘group augmentation hypothesis’. Predators forced helpers to stay closer to, and spend more time inside, protective shelters. The results demonstrate the importance of predators for group living in this species, and support the ‘ecological constraints hypothesis’ of cooperative breeding, in the sense that subordinates stay at home rather than leave and breed independently under the risk of predation.

Clinical outcomes of patients with estimated low or intermediate surgical risk undergoing transcatheter aortic valve implantation

AIMS Transcatheter aortic valve implantation (TAVI) is an established treatment alternative to surgical aortic valve replacement in high-risk and inoperable patients and outcomes among patients with estimated low or intermediate risk remain to be determined. The aim of this study was to assess clinical outcomes among patients with estimated low or intermediate surgical risk undergoing TAVI. METHODS AND RESULTS Between August 2007 and October 2011, 389 consecutive patients underwent TAVI and were categorized according to the Society of Thoracic Surgeons (STS) score into low (STS < 3%; n = 41, 10.5%), intermediate (STS ≥3% and ≤8%, n = 254, 65.3%), and high-risk (STS > 8%; n = 94, 24.2%) groups for the purpose of this study. Significant differences were found between the groups (low risk vs. intermediate risk vs. high risk) for age (78.2 ± 6.7 vs. 82.7 ± 5.7 vs. 83.7 ± 4.9, P < 0.001), body mass index (28.1 ± 6.1 vs. 26.5 ± 4.9 vs. 24.4 ± 4.6, P < 0.001), chronic renal failure (34 vs. 67 vs. 90%, P < 0.001), all-cause mortality at 30 days (2.4 vs. 3.9 vs. 14.9%, P = 0.001), and all-cause mortality at 1 year (10.1 vs. 16.1 vs. 34.5%, P = 0.0003). No differences were observed with regards to cerebrovascular accidents and myocardial infarction during 1-year follow-up. CONCLUSION In contemporary practice, TAVI is not limited to inoperable or STS-defined high-risk patients and should be guided by the decision of an interdisciplinary Heart Team. Compared with patients at calculated high risk, well-selected patients with STS-defined intermediate or low risk appear to have favourable clinical outcomes.

Helpers in a cooperatively breeding cichlid stay and pay or disperse and breed, depending on ecological constraints

The theory of family–group dynamics predicts that group structure, helping behaviour and social interactions among group members should vary with the opportunities of subordinates to breed independently. We investigated experimentally whether unrelated mature helpers in the cooperatively breeding cichlid Neolamprologus pulcher reduce costly social and cooperative behaviour and choose to disperse and breed independently when offered vacant breeding sites. As predicted by the ecological constraints hypothesis, when breeding substrate was available, (i) helpers spent more time in dispersal areas and it was mainly large helpers that left the group to breed independently; (ii) all helpers invested less in costly submissive behaviours towards other group members and large helpers reduced help, supporting the ‘pay–to–stay’ hypothesis; and (iii) large helpers, particularly those that dispersed and bred, increased more in body mass in the treatment than those without breeding options, suggesting status–dependent strategic growth of helpers. We conclude that helpers of N. pulcher decide whether to stay and pay or disperse and breed in response to constraints on independent breeding.

Derivation and validation of the predicting bleeding complications in patients undergoing stent implantation and subsequent dual antiplatelet therapy (PRECISE-DAPT) score: a pooled analysis of individual-patient datasets from clinical trials

BACKGROUND Dual antiplatelet therapy (DAPT) with aspirin plus a P2Y12 inhibitor prevents ischaemic events after coronary stenting, but increases bleeding. Guidelines support weighting bleeding risk before the selection of treatment duration, but no standardised tool exists for this purpose. METHODS A total of 14 963 patients treated with DAPT after coronary stenting-largely consisting of aspirin and clopidogrel and without indication to oral anticoagulation-were pooled at a single-patient level from eight multicentre randomised clinical trials with independent adjudication of events. Using Cox proportional hazards regression, we identified predictors of out-of-hospital Thrombosis in Myocardial Infarction (TIMI) major or minor bleeding stratified by trial, and developed a numerical bleeding risk score. The predictive performance of the novel score was assessed in the derivation cohort and validated in patients treated with percutaneous coronary intervention from the PLATelet inhibition and patient Outcomes (PLATO) trial (n=8595) and BernPCI registry (n=6172). The novel score was assessed within patients randomised to different DAPT durations (n=10 081) to identify the effect on bleeding and ischaemia of a long (12-24 months) or short (3-6 months) treatment in relation to baseline bleeding risk. FINDINGS The PRECISE-DAPT score (age, creatinine clearance, haemoglobin, white-blood-cell count, and previous spontaneous bleeding) showed a c-index for out-of-hospital TIMI major or minor bleeding of 0·73 (95% CI 0·61-0·85) in the derivation cohort, and 0·70 (0·65-0·74) in the PLATO trial validation cohort and 0·66 (0·61-0·71) in the BernPCI registry validation cohort. A longer DAPT duration significantly increased bleeding in patients at high risk (score ≥25), but not in those with lower risk profiles (pinteraction=0·007), and exerted a significant ischaemic benefit only in this latter group. INTERPRETATION The PRECISE-DAPT score is a simple five-item risk score, which provides a standardised tool for the prediction of out-of-hospital bleeding during DAPT. In the context of a comprehensive clinical evaluation process, this tool can support clinical decision making for treatment duration. FUNDING None.

Ultrathin strut biodegradable polymer sirolimus-eluting stent versus durable polymer everolimus-eluting stent for percutaneous coronary revascularisation (BIOSCIENCE): a randomised, single-blind, non-inferiority trial

BACKGROUND Refinements in stent design affecting strut thickness, surface polymer, and drug release have improved clinical outcomes of drug-eluting stents. We aimed to compare the safety and efficacy of a novel, ultrathin strut cobalt-chromium stent releasing sirolimus from a biodegradable polymer with a thin strut durable polymer everolimus-eluting stent. METHODS We did a randomised, single-blind, non-inferiority trial with minimum exclusion criteria at nine hospitals in Switzerland. We randomly assigned (1:1) patients aged 18 years or older with chronic stable coronary artery disease or acute coronary syndromes undergoing percutaneous coronary intervention to treatment with biodegradable polymer sirolimus-eluting stents or durable polymer everolimus-eluting stents. Randomisation was via a central web-based system and stratified by centre and presence of ST segment elevation myocardial infarction. Patients and outcome assessors were masked to treatment allocation, but treating physicians were not. The primary endpoint, target lesion failure, was a composite of cardiac death, target vessel myocardial infarction, and clinically-indicated target lesion revascularisation at 12 months. A margin of 3·5% was defined for non-inferiority of the biodegradable polymer sirolimus-eluting stent compared with the durable polymer everolimus-eluting stent. Analysis was by intention to treat. The trial is registered with ClinicalTrials.gov, number NCT01443104. FINDINGS Between Feb 24, 2012, and May 22, 2013, we randomly assigned 2119 patients with 3139 lesions to treatment with sirolimus-eluting stents (1063 patients, 1594 lesions) or everolimus-eluting stents (1056 patients, 1545 lesions). 407 (19%) patients presented with ST-segment elevation myocardial infarction. Target lesion failure with biodegradable polymer sirolimus-eluting stents (69 cases; 6·5%) was non-inferior to durable polymer everolimus-eluting stents (70 cases; 6·6%) at 12 months (absolute risk difference -0·14%, upper limit of one-sided 95% CI 1·97%, p for non-inferiority <0·0004). No significant differences were noted in rates of definite stent thrombosis (9 [0·9%] vs 4 [0·4%], rate ratio [RR] 2·26, 95% CI 0·70-7·33, p=0·16). In pre-specified stratified analyses of the primary endpoint, biodegradable polymer sirolimus-eluting stents were associated with improved outcome compared with durable polymer everolimus-eluting stents in the subgroup of patients with ST-segment elevation myocardial infarction (7 [3·3%] vs 17 [8·7%], RR 0·38, 95% CI 0·16-0·91, p=0·024, p for interaction=0·014). INTERPRETATION In a patient population with minimum exclusion criteria and high adherence to dual antiplatelet therapy, biodegradable polymer sirolimus-eluting stents were non-inferior to durable polymer everolimus-eluting stents for the combined safety and efficacy outcome target lesion failure at 12 months. The noted benefit in the subgroup of patients with ST-segment elevation myocardial infarction needs further study. FUNDING Clinical Trials Unit, University of Bern, and Biotronik, Bülach, Switzerland.