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16 result(s) for "Stables, Rod H."
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Unfractionated heparin versus bivalirudin in primary percutaneous coronary intervention (HEAT-PPCI): an open-label, single centre, randomised controlled trial
Bivalirudin, with selective use of glycoprotein (GP) IIb/IIIa inhibitor agents, is an accepted standard of care in primary percutaneous coronary intervention (PPCI). We aimed to compare antithrombotic therapy with bivalirudin or unfractionated heparin during this procedure. In our open-label, randomised controlled trial, we enrolled consecutive adults scheduled for angiography in the context of a PPCI presentation at Liverpool Heart and Chest Hospital (Liverpool, UK) with a strategy of delayed consent. Before angiography, we randomly allocated patients (1:1; stratified by age [<75 years vs ≥75 years] and presence of cardiogenic shock [yes vs no]) to heparin (70 U/kg) or bivalirudin (bolus 0·75 mg/kg; infusion 1·75 mg/kg per h). Patients were followed up for 28 days. The primary efficacy outcome was a composite of all-cause mortality, cerebrovascular accident, reinfarction, or unplanned target lesion revascularisation. The primary safety outcome was incidence of major bleeding (type 3–5 as per Bleeding Academic Research Consortium definitions). This study is registered with ClinicalTrials.gov, number NCT01519518. Between Feb 7, 2012, and Nov 20, 2013, 1829 of 1917 patients undergoing emergency angiography at our centre (representing 97% of trial-naive presentations) were randomly allocated treatment, with 1812 included in the final analyses. 751 (83%) of 905 patients in the bivalirudin group and 740 (82%) of 907 patients in the heparin group had a percutaneous coronary intervention. The rate of GP IIb/IIIa inhibitor use was much the same between groups (122 patients [13%] in the bivalirudin group and 140 patients [15%] in the heparin group). The primary efficacy outcome occurred in 79 (8·7%) of 905 patients in the bivalirudin group and 52 (5·7%) of 907 patients in the heparin group (absolute risk difference 3·0%; relative risk [RR] 1·52, 95% CI 1·09–2·13, p=0·01). The primary safety outcome occurred in 32 (3·5%) of 905 patients in the bivalirudin group and 28 (3·1%) of 907 patients in the heparin group (0·4%; 1·15, 0·70–1·89, p=0·59). Compared with bivalirudin, heparin reduces the incidence of major adverse ischaemic events in the setting of PPCI, with no increase in bleeding complications. Systematic use of heparin rather than bivalirudin would reduce drug costs substantially. Liverpool Heart and Chest Hospital, UK National Institute of Health Research, The Medicines Company, AstraZeneca, The Bentley Drivers Club (UK).
High Platelet Reactivity in Patients with Acute Coronary Syndromes Undergoing Percutaneous Coronary Intervention: Randomised Controlled Trial Comparing Prasugrel and Clopidogrel
Prasugrel is more effective than clopidogrel in reducing platelet aggregation in acute coronary syndromes. Data available on prasugrel reloading in clopidogrel treated patients with high residual platelet reactivity (HRPR) i.e. poor responders, is limited. To determine the effects of prasugrel loading on platelet function in patients on clopidogrel and high platelet reactivity undergoing percutaneous coronary intervention for acute coronary syndrome (ACS). Patients with ACS on clopidogrel who were scheduled for PCI found to have a platelet reactivity ≥40 AUC with the Multiplate Analyzer, i.e. \"poor responders\" were randomised to prasugrel (60 mg loading and 10 mg maintenance dose) or clopidogrel (600 mg reloading and 150 mg maintenance dose). The primary outcome measure was proportion of patients with platelet reactivity <40 AUC 4 hours after loading with study medication, and also at one hour (secondary outcome). 44 patients were enrolled and the study was terminated early as clopidogrel use decreased sharply due to introduction of newer P2Y12 inhibitors. At 4 hours after study medication 100% of patients treated with prasugrel compared to 91% of those treated with clopidogrel had platelet reactivity <40 AUC (p = 0.49), while at 1 hour the proportions were 95% and 64% respectively (p = 0.02). Mean platelet reactivity at 4 and 1 hours after study medication in prasugrel and clopidogrel groups respectively were 12 versus 22 (p = 0.005) and 19 versus 34 (p = 0.01) respectively. Routine platelet function testing identifies patients with high residual platelet reactivity (\"poor responders\") on clopidogrel. A strategy of prasugrel rather than clopidogrel reloading results in earlier and more sustained suppression of platelet reactivity. Future trials need to identify if this translates into clinical benefit. ClinicalTrials.gov NCT01339026.
Bivalirudin versus heparin use for patients undergoing PPCI – Authors' reply
To determine the relative safety of heparin and bivalirudin in studies with differential use of glycoprotein (GP) IIb/IIIa inhibitor drugs is impossible.5 Observational data, such as from EUROMAX4 for patients treated with heparin, are interesting but cannot be regarded as definitive. The reported rate in HEAT-PPCI1 matches institutional and national norms, whereas in HORIZONS-AMI2 (2·6%), EUROMAX4 (3·0%) and BRIGHT3 (1·9%) it is less than half that declared in the national registries (UK 30-day mortality is 6·4% as per British Cardiovascular Intervention Society's audit data in 2012;7 USA inpatient mortality is 5·7% as per Diagnostic Catheterization and Percutaneous Coronary Intervention [CathPCI] Registry data in 2011).
Radial versus femoral vascular access in ST-elevation myocardial infarction: Are the results of femoral operators unfairly represented in observational research?
Recent randomized controlled trials comparing femoral and radial access in primary percutaneous coronary intervention (PPCI) have shown conflicting results regarding the incidence of major adverse cardiovascular events (MACE) and major bleeding. Using data from the HEAT-PPCI trial, we compared the primary efficacy (all-cause mortality, stroke, new myocardial infarction or unplanned repeat revascularization) and safety (major bleeding BARC 3–5) outcomes at 28 days, by final access site used (radial or femoral) and by default operator type. We then assessed outcomes in femoral cases performed by both operator types. Radial access (RA) was associated with fewer MACE (91/1472 = 6.2% vs. 36/332 = 10.8% P = .003) and major bleeding events (38/1472 = 2.6% vs 22/332 = 6.6% P = .001) when compared to femoral access (FA). When analyzing outcomes by default operator type, there was a similar incidence of MACE (111/1575 = 7% vs 16/229 = 7% P = .97) and major bleeding events (49/1575 = 3.1% vs 11/229 = 4.8% P = .18). In cases where FA was performed by default radial operators, there was a higher rate of MACE (22/122 = 18% vs 14/210 = 6.7% P = .003) and major bleeding events (11/122 = 9% vs 11/210 = 5.2% P < .001), potentially explained by a higher risk profile in these cases. Default femoral operators achieved comparable outcomes when compared to default radial operators. The less favorable outcomes observed in FA cases may result from its selective use by radial operators in high risk cases.
Bivalirudin versus Heparin Monotherapy in Myocardial Infarction
To the Editor: In the VALIDATE-SWEDEHEART trial, Erlinge et al. (Sept. 21 issue) 1 compared bivalirudin with heparin monotherapy in patients with acute myocardial infarction who were undergoing percutaneous coronary intervention (PCI). Treatment included the use of one of the new P2Y 12 inhibitors (ticagrelor, cangrelor, or prasugrel), which was given at least 60 minutes before PCI. Patients who received or were planned to receive glycoprotein IIb/IIIa inhibitors were excluded from enrollment, and the low rates of ischemic events and stent thrombosis are probably attributable to the early administration of the new P2Y 12 inhibitors. In the current era, in which immediate reperfusion . . .
A comparison of hospital episode statistics and traditional methods to identify outcomes in a randomized trial; a sub-study of HEAT-PPCI
Abstract Background This study aims to compare information from hospital episode statistics (HES) and traditional direct patient contact to identify readmission and clinical events in the follow-up of a randomized controlled trial (RCT). Methods The study followed 1812 patients for 28 days using direct contact (DC). In addition, we obtained HES for this period. We examined medical records for all suspected readmissions and determined confirmed events by adjudication. We compared the ability of the individual DC and HES methods to determine readmission and the occurrence of trial-specific events, confirmed at adjudication. Results In the ascertainment of readmission, compared to DC, HES demonstrated a trend towards better sensitivity (identifying 153/166 = 92.2% versus 144/166 = 86.7%; difference = 5.4%, 95% CI: 0.1–11.5%) and better specificity (1492/1492 = 100% versus 1426/1492 = 95.5%; difference = 4.4%, 95% CI: 4.2–5.6%). An examination of HES coding does not identify rates for specific events that match those from adjudication, with limitations in both sensitivity and specificity. Conclusion HES is effective in the ascertainment of readmission and is a useful tool in follow-up. Information from HES provides a reflection of a patient’s course and associated cost, as perceived by the healthcare system. Future studies could modify outcome definitions to reflect episode coding.
Validation of high temporal resolution spiral phase velocity mapping of temporal patterns of left and right coronary artery blood flow against Doppler guidewire
Background Temporal patterns of coronary blood flow velocity can provide important information on disease state and are currently assessed invasively using a Doppler guidewire. A non-invasive alternative would be beneficial as it would allow study of a wider patient population and serial scanning. Methods A retrospectively-gated breath-hold spiral phase velocity mapping sequence (TR 19 ms) was developed at 3 Tesla. Velocity maps were acquired in 8 proximal right and 15 proximal left coronary arteries of 18 subjects who had previously had a Doppler guidewire study at the time of coronary angiography. Cardiovascular magnetic resonance (CMR) velocity-time curves were processed semi-automatically and compared with corresponding invasive Doppler data. Results When corrected for differences in heart rate between the two studies, CMR mean velocity through the cardiac cycle, peak systolic velocity (PSV) and peak diastolic velocity (PDV) were approximately 40 % of the peak Doppler values with a moderate - good linear relationship between the two techniques (R 2 : 0.57, 0.64 and 0.79 respectively). CMR values of PDV/PSV showed a strong linear relationship with Doppler values with a slope close to unity (0.89 and 0.90 for right and left arteries respectively). In individual vessels, plots of CMR velocities at all cardiac phases against corresponding Doppler velocities showed a consistent linear relationship between the two with high R 2 values (mean +/−SD: 0.79 +/−.13). Conclusions High temporal resolution breath-hold spiral phase velocity mapping underestimates absolute values of coronary flow velocity but allows accurate assessment of the temporal patterns of blood flow.
Feasibility of cardiovascular magnetic resonance derived coronary wave intensity analysis
Wave intensity analysis (WIA) of the coronary arteries allows description of the predominant mechanisms influencing coronary flow over the cardiac cycle. The data are traditionally derived from pressure and velocity changes measured invasively in the coronary artery. Cardiovascular magnetic resonance (CMR) allows measurement of coronary velocities using phase velocity mapping and derivation of central aortic pressure from aortic distension. We assessed the feasibility of WIA of the coronary arteries using CMR and compared this to invasive data. CMR scans were undertaken in a serial cohort of patients who had undergone invasive WIA. Velocity maps were acquired in the proximal left anterior descending and proximal right coronary artery using a retrospectively-gated breath-hold spiral phase velocity mapping sequence with high temporal resolution (19 ms). A breath-hold segmented gradient echo sequence was used to acquire through-plane cross sectional area changes in the proximal ascending aorta which were used as a surrogate of an aortic pressure waveform after calibration with brachial blood pressure measured with a sphygmomanometer. CMR-derived aortic pressures and CMR-measured velocities were used to derive wave intensity. The CMR-derived wave intensities were compared to invasive data in 12 coronary arteries (8 left, 4 right). Waves were presented as absolute values and as a % of total wave intensity. Intra-study reproducibility of invasive and non-invasive WIA was assessed using Bland-Altman analysis and the intraclass correlation coefficient (ICC). The combination of the CMR-derived pressure and velocity data produced the expected pattern of forward and backward compression and expansion waves. The intra-study reproducibility of the CMR derived wave intensities as a % of the total wave intensity (mean ± standard deviation of differences) was 0.0 ± 6.8%, ICC = 0.91. Intra-study reproducibility for the corresponding invasive data was 0.0 ± 4.4%, ICC = 0.96. The invasive and CMR studies showed reasonable correlation (r = 0.73) with a mean difference of 0.0 ± 11.5%. This proof of concept study demonstrated that CMR may be used to perform coronary WIA non-invasively with reasonable reproducibility compared to invasive WIA. The technique potentially allows WIA to be performed in a wider range of patients and pathologies than those who can be studied invasively.
Association between post-percutaneous coronary intervention bivalirudin infusion and net adverse clinical events: a post hoc analysis of the GLOBAL LEADERS study
Abstract Aims The efficacy and safety of continued bivalirudin infusion after percutaneous coronary intervention (PCI) remains uncertain. We sought to investigate the association between post-PCI bivalirudin infusion and the risk of net adverse clinical events (NACE) at 30 days. Methods and results In the GLOBAL LEADERS study, all patients who received bivalirudin during PCI were categorized according to the use of bivalirudin infusion after the procedure. The primary endpoint of the present analysis was NACE [a composite of all-cause death, any stroke, any myocardial infarction, all revascularization, and bleeding assessed according to the Bleeding Academic Research Consortium (BARC) criteria Type 3 or 5] at 30 days. The key safety endpoint was BARC Type 3 or 5 bleeding and definite stent thrombosis. Of 15 968 patients, 13 870 underwent PCI with the use of bivalirudin. In total, 7148 patients received continued bivalirudin infusion after procedure, while 6722 patients received standard care. After propensity score covariate adjustment, the risk of NACE did not significantly differ between two treatments after PCI [continued bivalirudin infusion vs. no bivalirudin infusion: 3.2% vs. 3.1%, adjusted hazard ratio (aHR) 1.35, 95% confidence interval (CI) 0.99–1.84, P = 0.06] nor the BARC Type 3 or 5 bleeding (0.7% vs. 0.7%, aHR 0.89, 95% CI 0.44–1.79; P = 0.743) and definite stent thrombosis (0.5% vs. 0.3%, aHR 1.71, 95% CI 0.77–3.81, P = 0.189). However, continued bivalirudin infusion was associated with an increased risk of NACE and definite stent thrombosis in ST-elevation myocardial infarction (STEMI) patients. Conclusion In an all-comers population undergoing PCI, there was no significant difference in the risk of NACE at 30 days between continued bivalirudin infusion vs. no bivalirudin infusion after procedure but continued bivalirudin infusion was associated with a higher risk of NACE in STEMI patients when compared with no infusion.