Prognostic Value of Microvascular Resistance Reserve After Percutaneous Coronary Intervention in Patients With Myocardial Infarction.

BACKGROUND: The microvascular resistance reserve (MRR) has recently been introduced as a novel index to assess the vasodilatory capacity of the microcirculation, independent of epicardial disease. The prognostic value of MRR in ST-segment elevation myocardial infarction (STEMI) is unknown. OBJECTIVES: The aim of this analysis was to investigate the prognostic value of MRR in patients with STEMI and to compare MRR with cardiovascular magnetic resonance imaging parameters. METHODS: From a pooled analysis of individual patient data from 6 cohorts that measured the index of microcirculatory resistance (IMR) directly after primary percutaneous coronary intervention in patients with STEMI (n = 1,265), a subgroup analysis was performed in patients in whom both MRR and IMR were available. The primary endpoint was the composite of all-cause mortality or hospitalization for heart failure. RESULTS: Both MRR and IMR could be calculated in 446 patients. The optimal cutoff of MRR to predict the primary endpoint in this STEMI population was 1.25. During a median follow-up of 3.1 years (Q1-Q3: 1.5-6.1 years), the composite of all-cause mortality or hospitalization for heart failure occurred in 27.3% and 5.9% of patients (HR: 4.16; 95% CI: 2.31-7.50; P < 0.001) in the low MRR (≤1.25) and high MRR (>1.25) groups, respectively. Both IMR and MRR were independent predictors of the composite of all-cause mortality or hospitalization for heart failure. CONCLUSIONS: MRR measured directly after primary percutaneous coronary intervention was an independent predictor of the composite of all-cause mortality or hospitalization for heart failure during long-term follow-up.

Ultrasound-guided versus fluoroscopy-guided large-bore femoral access in PCI of complex coronary lesions: the international, multicentre, randomised ULTRACOLOR Trial.

BACKGROUND: Transfemoral access is often used when large-bore guide catheters are required for percutaneous coronary intervention (PCI) of complex coronary lesions, especially when large-bore transradial access is contraindicated. Whether the risk of access site complications for these procedures may be reduced by ultrasound-guided puncture is unclear. AIMS: We aimed to show the superiority of ultrasound-guided femoral puncture compared to fluoroscopy-guided access in large-bore complex PCI with regard to access site-related Bleeding Academic Research Consortium 2, 3 or 5 bleeding and/or vascular complications requiring intervention during hospitalisation. METHODS: The ULTRACOLOR Trial is an international, multicentre, randomised controlled trial investigating whether ultrasound-guided large-bore femoral access reduces clinically relevant access site complications compared to fluoroscopy-guided large-bore femoral access in PCI of complex coronary lesions. RESULTS: A total of 544 patients undergoing complex PCI mandating large-bore (≥7 Fr) transfemoral access were randomised at 10 European centres (median age 71; 76% male). Of these patients, 68% required PCI of a chronic total occlusion. The primary endpoint was met in 18.9% of PCI with fluoroscopy-guided access and 15.7% of PCI with ultrasound-guided access (p=0.32). First-pass puncture success was 92% for ultrasound-guided access versus 85% for fluoroscopy-guided access (p=0.02). The median time in the catheterisation laboratory was 102 minutes versus 105 minutes (p=0.43), and the major adverse cardiovascular event rate at 1 month was 4.1% for fluoroscopy-guided access and 2.6% for ultrasound-guided access (p=0.32). CONCLUSIONS: As compared to fluoroscopy-guided access, the routine use of ultrasound-guided access for large-bore transfemoral complex PCI did not significantly reduce clinically relevant bleeding or vascular access site complications. A significantly higher first-pass puncture success rate was demonstrated for ultrasound-guided access. CLINICALTRIALS: gov identifier: NCT04837404.

Impact of symptom-to-reperfusion-time on transmural infarct extent and left ventricular strain in patients with ST-segment elevation myocardial infarction: a 3D view on the wavefront phenomenon.

AIMS: We examined the association between the symptom-to-reperfusion-time and cardiovascular magnetic resonance (CMR)-derived global strain parameters and transmural infarct extent in ST-segment elevation myocardial infarction (STEMI) patients. METHODS AND RESULTS: The study included 108 STEMI patients who underwent successful primary percutaneous coronary intervention (PPCI). Patients were categorized according to the median symptom-to-reperfusion-time: shorter (<160 min, n = 54) and longer times (>160 min, n = 54). CMR was performed 2-7 days after PPCI and at 1 month. CMR cine imaging was performed for functional assessment and late gadolinium enhancement to evaluate transmural infarct extent. Myocardial feature-tracking was used for strain analysis. Groups were comparable in relation to incidence of LAD disease and pre- and post-PPCI thrombolysis in myocardial infarction (TIMI) flow grades. The mean transmural extent score at follow-up was lower in patients with shorter reperfusion time (P < 0.01). Both baseline and follow-up maximum transmural extent scores were smaller in patients with shorter reperfusion time (P = 0.03 for both). Patients with shorter reperfusion time had more favourable global left ventricular (LV) circumferential strain (baseline, P = 0.049; follow-up, P = 0.01) and radial strain (baseline, P = 0.047; follow-up, P < 0.01), whilst LV longitudinal strain appeared comparable for both baseline and follow-up (P > 0.05 for both). In multi-variable regression analysis including all three strain directions, baseline LV circumferential strain was independently associated with the mean transmural extent score at follow-up (ß=1.89, P < 0.001). CONCLUSION: In STEMI patients, time-to-reperfusion was significantly associated with smaller transmural extent of infarction and better LV circumferential and radial strain. Moreover, infarct transmurality and residual LV circumferential strain are closely linked.

The Index of Microcirculatory Resistance After Primary PCI: A Pooled Analysis of Individual Patient Data.

BACKGROUND: Despite treatment with primary percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction (STEMI), the risk of heart failure and late death remains high. Microvascular dysfunction, as assessed by the index of microcirculatory resistance (IMR), after primary PCI for STEMI has been associated with worse outcomes. It is unclear whether IMR after primary PCI predicts cardiac death. OBJECTIVES: The aims of this analysis were: 1) to determine if IMR is an independent predictor of cardiac death; 2) to assess the optimal cutoff value of IMR after STEMI; and 3) to compare IMR with several cardiac magnetic resonance parameters, including infarct size. METHODS: In a collaborative, pooled analysis of individual patient data from 6 cohorts that measured IMR directly after primary PCI, cardiac mortality up to 5 years was estimated using Kaplan-Meier analyses. The primary endpoint was cardiac death using the predefined IMR cutoff value of 40. RESULTS: In total, 1,265 patients were included in this study with a median follow-up of 2.8 years (IQR: 1.2-5.0 years). Cardiac death at 5 years occurred in 2.2% and 4.9% of patients (HR: 2.81; 95% CI: 1.34-5.88; P = 0.006) in the IMR ≤40 and IMR >40 groups, respectively. The composite of cardiac death or hospitalization for heart failure occurred in 4.9% and 8.9% (HR: 1.98; 95% CI: 1.20-3.29; P = 0.008) in the IMR ≤40 and IMR >40 groups, respectively. IMR was an independent predictor of cardiac death, whereas coronary flow reserve was not. The optimal cutoff value of IMR for the prediction of cardiac death in this cohort was 70 (HR: 4.73; 95% CI: 2.27-9.83; P < 0.001). Infarct size was 17.6% ± 13.3% and 23.9% ± 14.6% of the left ventricular mass in the IMR ≤40 and IMR >40 groups, respectively (P < 0.001). Microvascular obstruction and intramyocardial hemorrhage occurred more frequently in the IMR >40 group than in the IMR ≤40 group. CONCLUSIONS: In this large, pooled analysis of individual patient data, IMR measured directly after primary PCI in STEMI was an independent predictor of cardiac death. IMR may be used as a tool to identify patients at the time of primary PCI who are at highest risk for late cardiac mortality and who might benefit most from additional cardioprotective therapies and monitoring.

Fractional Flow Reserve-Negative High-Risk Plaques and Clinical Outcomes After Myocardial Infarction.

Importance: Even after fractional flow reserve (FFR)-guided complete revascularization, patients with myocardial infarction (MI) have high rates of recurrent major adverse cardiovascular events (MACE). These recurrences may be caused by FFR-negative high-risk nonculprit lesions. Objective: To assess the association between optical coherence tomography (OCT)-identified high-risk plaques of FFR-negative nonculprit lesions and occurrence of MACE in patients with MI. Design, Setting, and Participants: PECTUS-obs (Identification of Risk Factors for Acute Coronary Events by OCT After STEMI [ST-segment elevation MI] and NSTEMI [non-STEMI] in Patients With Residual Non-flow Limiting Lesions) is an international, multicenter, prospective, observational cohort study. In patients presenting with MI, OCT was performed on all FFR-negative (FFR > 0.80) nonculprit lesions. A high-risk plaque was defined containing at least 2 of the following prespecified criteria: (1) a lipid arc at least 90°, (2) a fibrous cap thickness less than 65 µm, and (3) either plaque rupture or thrombus presence. Patients were enrolled from December 14, 2018, to September 15, 2020. Data were analyzed from December 2, 2022, to June 28, 2023. Main Outcome and Measure: The primary end point of MACE, a composite of all-cause mortality, nonfatal MI, or unplanned revascularization, at 2-year follow-up was compared in patients with and without a high-risk plaque. Results: A total of 438 patients were enrolled, and OCT findings were analyzable in 420. Among included patients, mean (SD) age was 63 (10) years, 340 (81.0) were men, and STEMI and non-STEMI were equally represented (217 [51.7%] and 203 [48.3%]). A mean (SD) of 1.17 (0.42) nonculprit lesions per patient was imaged. Analysis of OCT images revealed at least 1 high-risk plaque in 143 patients (34.0%). The primary end point occurred in 22 patients (15.4%) with a high-risk plaque and 23 of 277 patients (8.3%) without a high-risk plaque (hazard ratio, 1.93 [95% CI, 1.08-3.47]; P = .02), primarily driven by more unplanned revascularizations in patients with a high-risk plaque (14 of 143 [9.8%] vs 12 of 277 [4.3%]; P = .02). Conclusions and Relevance: Among patients with MI and FFR-negative nonculprit lesions, the presence of a high-risk plaque is associated with a worse clinical outcome, which is mainly driven by a higher number of unplanned revascularizations. In a population with a high recurrent event rate despite physiology-guided complete revascularization, these results call for research on additional pharmacological or focal treatment strategies in patients harboring high-risk plaques.

Vascular Access in Percutaneous Coronary Intervention of Chronic Total Occlusions: A State-of-the-Art Review.

The outcomes of chronic total occlusion percutaneous coronary intervention have considerably improved during the last decade with continued emphasis on improving procedural safety. Vascular access site bleeding remains one of the most frequent complications. Several procedural strategies have been implemented to reduce the rate of vascular access site complications. This state-of-the-art review summarizes and describes the current evidence on optimal vascular access strategies for chronic total occlusion percutaneous coronary intervention.

Effect of ticagrelor and prasugrel on remote myocardial inflammation in patients with acute myocardial infarction with ST-elevation: a CMR T1 and T2 mapping study.

PURPOSE: Acute myocardial ischaemia triggers a non-specific inflammatory response of remote myocardium through the increase of plasma concentrations of acute-phase proteins, which causes myocardial oedema. As ticagrelor has been shown to significantly decrease circulating levels of several pro-inflammatory cytokines in patients after acute myocardial infarction with ST-elevation (STEMI), we sought to investigate a potential suppressive effect of ticagrelor over prasugrel on cardiac magnetic resonance (CMR) T1 and T2 values in remote myocardium. METHODS: Ninety STEMI patients were prospectively included and randomised to receive either ticagrelor or prasugrel maintenance treatment after successful primary percutaneous coronary intervention. Patients underwent CMR after 2-7 days. The protocol included long and short axis cine imaging, T1 mapping, T2 mapping and late gadolinium enhancement imaging. RESULTS: After excluding 30 patients due to either missing images or insufficient quality of the T1 or T2 maps, 60 patients were included in our analysis. Of those, 29 patients were randomised to the ticagrelor group and 31 patients to the prasugrel group. In the remote myocardium, T1 values did not differ between groups (931.3 [919.4-950.4] ms for ticagrelor vs. 932.6 [915.5-949.2] ms for prasugrel (p = 0.94)), nor did the T2 values (53.8 ± 4.6 ms for ticagrelor vs. 53.7 ± 4.7 ms for prasugrel (p = 0.86)). Also, in the infarcted myocardium, T1 and T2 values did not differ between groups. CONCLUSION: In revascularised STEMI patients, ticagrelor maintenance therapy did not show superiority over prasugrel in preventing early remote myocardial inflammation as assessed by CMR T1 and T2 mapping.

ULTrasound-guided TRAnsfemoral puncture in COmplex Large bORe PCI: study protocol of the UltraCOLOR trial.

INTRODUCTION: Although recently published evidence favours transradial access (TRA) when using large-bore guiding catheters for percutaneous coronary intervention (PCI) of complex coronary lesions, the femoral artery will still be used in a considerate proportion of patients undergoing complex PCI, especially in PCI of chronic total occlusions (CTO). Ultrasound-guided puncture of the femoral artery may reduce clinically relevant access site complications, but robust evidence is lacking up to date. METHODS AND ANALYSIS: A total of 542 patients undergoing complex PCI, defined as PCI of CTO, complex bifurcation, heavy calcified lesion or left main, in which the 7-F or 8-F transfemoral access is required, will be randomised to ultrasound-guided puncture or fluoroscopy-guided puncture. The primary outcome is the incidence of the composite end-point of clinically relevant access site related bleeding and/or vascular complications requiring intervention. Access site complications and major adverse cardiovascular events up to 1 month will also be compared between both groups. ETHICS AND DISSEMINATION: Ethical approval for the study was granted by the local Ethics Committee ('Medisch Ethische Toetsing Commissie Isala Zwolle') for all Dutch sites, 'Comité Medische Ethiek Ziekenhuis Oost-Limburg' for Hospital Oost-Limburg, 'Comité d'éthique CHU-Charleroi-ISPPC' for Centre Hospilatier Universitaire de Charleroi and 'Ethik Kommission de Ärztekammer Nordrhein' for Elisabeth-Krankenhaus). The trial outcomes will be published in peer-reviewed journals of the concerned literature. The ultrasound guided transfemoral access in complex large bore PCI trial has been administered in the ClinicalTrials.gov database, reference number: NCT03846752. REGISTRATION DETAILS: ClinicalTrials.gov identifier: NCT03846752.

Current and Future Insights for Optimizing Antithrombotic Therapy to Reduce the Burden of Cardiovascular Ischemic Events in Patients with Acute Coronary Syndrome.

The pharmacological treatment strategies for acute coronary syndrome (ACS) in recent years are constantly evolving to develop more potent antithrombotic agents, as reflected by the introduction of more novel P2Y12 receptor inhibitors and anticoagulants to reduce the ischemic risk among ACS patients. Despite the substantial improvements in the current antithrombotic regimen, a noticeable number of ACS patients continue to experience ischemic events. Providing effective ischemic risk reduction while balancing bleeding risk remains a clinical challenge. This updated review discusses the currently approved and widely used antithrombotic agents and explores newer antithrombotic treatment strategies under development for the initial phase of ACS.

The Dynamic Relationship Between Invasive Microvascular Function and Microvascular Injury Indicators, and Their Association With Left Ventricular Function and Infarct Size at 1-Month After Reperfused ST-Segment-Elevation Myocardial Infarction.

BACKGROUND: The invasive microvascular function indices, coronary flow reserve (CFR) and the index of microcirculatory resistance (IMR), exhibit a dynamic pattern after ST-segment-elevation myocardial infarction. The effects of microvascular injury on the evolution of the microvascular function and the prognostic significance of the evolution of microvascular function are unknown. We investigated the relationship between the temporal changes of CFR and IMR, and cardiovascular magnetic resonance-derived microvascular injury characteristics in reperfused ST-segment-elevation myocardial infarction patients, and their association with 1-month left ventricular ejection fraction and infarct size (IS). METHODS: In 109 ST-segment-elevation myocardial infarction patients who underwent angiography for primary percutaneous coronary intervention (PPCI) and at 1-month follow-up, invasive assessment of CFR and IMR were performed in the culprit artery during both procedures. Cardiovascular magnetic resonance was performed 2 to 7 days after PPCI and at 1 month and provided assessment of left ventricular ejection fraction, IS, microvascular obstruction, and intramyocardial hemorrhage. RESULTS: CFR and IMR significantly changed over 1 month (both, P<0.001). The absolute IMR change over 1 month (ΔIMR) showed association with both microvascular obstruction and intramyocardial hemorrhage presence (both, P=0.01). ΔIMR differed between patients with/without microvascular obstruction (P=0.02) and with/without intramyocardial hemorrhage (P=0.04) but not ΔCFR for both. ΔIMR demonstrated association with both left ventricular ejection fraction and IS at 1 month (P<0.001, P=0.001, respectively), but not ΔCFR for both. Receiver-operating characteristics curve analysis of ΔIMR showed a larger area under the curve than post-PPCI CFR and IMR, and ΔCFR to be associated with both 1-month left ventricular ejection fraction >50% and extensive IS (the highest quartile). CONCLUSIONS: In reperfused ST-segment-elevation myocardial infarction patients, CFR and IMR significantly improved 1 month after PPCI; the temporal change in IMR is closely related to the presence/absence of microvascular damage and IS. ΔIMR exhibits a stronger association for 1-month functional outcome than post-PPCI CFR, IMR, or ΔCFR.

Effects on Mortality and Major Bleeding of Radial Versus Femoral Artery Access for Coronary Angiography or Percutaneous Coronary Intervention: Meta-Analysis of Individual Patient Data From 7 Multicenter Randomized Clinical Trials.

BACKGROUND: In some randomized clinical trials, transradial access (TRA) compared with transfemoral access (TFA) was associated with lower mortality in patients with coronary artery disease undergoing invasive management. We analyzed the effects of TRA versus TFA across multicenter randomized clinical trials and whether these associations are modified by patient or procedural characteristics. METHODS: We performed an individual patient data meta-analysis of multicenter randomized clinical trials comparing TRA with TFA among patients undergoing coronary angiography with or without percutaneous coronary intervention. The primary outcome was all-cause mortality and the co-primary outcome was major bleeding at 30 days. The primary analysis was conducted by 1-stage mixed-effects models on the basis of the intention-to-treat cohort. The effect of access site on mortality and major bleeding was assessed further by multivariable analysis. The relationship among access site, bleeding, and mortality was investigated by natural effect model mediation analysis with multivariable adjustment. RESULTS: A total of 21 600 patients (10 775 TRA, 10 825 TFA) from 7 randomized clinical trials were included. The median age was 63.9 years, 31.9% were women, 95% presented with acute coronary syndrome, and 75.2% underwent percutaneous coronary intervention. All-cause mortality (1.6% versus 2.1%; hazard ratio, 0.77 [95% CI, 0.63-0.95]; P=0.012) and major bleeding (1.5% versus 2.7%; odds ratio, 0.55 [95% CI, 0.45-0.67]; P<0.001) were lower with TRA. Subgroup analyses for mortality showed consistent results, except for baseline hemoglobin level (Pinteraction=0.003), indicating that the benefit of TRA was substantial in patients with moderate or severe anemia, whereas it was not significant in patients with milder or no baseline anemia. After adjustment, TRA remained associated with 24% and 51% relative risk reduction of all-cause mortality and major bleeding, respectively. A mediation analysis showed that the benefit of TRA on mortality was only partially driven by major bleeding prevention and ancillary mechanisms are required to fully explain the causal association. CONCLUSIONS: TRA is associated with lower all-cause mortality and major bleeding at 30 days compared with TFA. The effect on mortality was driven by patients with anemia. The reduction in major bleeding only partially explains the mortality benefit. REGISTRATION: URL: https://www.crd.york.ac.uk/prospero; Unique identifier: CRD42018109664.

Distal Versus Conventional Radial Access for Coronary Angiography and Intervention: The DISCO RADIAL Trial.

BACKGROUND: Currently, transradial access (TRA) is the recommended access for coronary procedures because of increased safety, with radial artery occlusion (RAO) being its most frequent complication, which will increasingly affect patients undergoing multiple procedures during their lifetimes. Recently, distal radial access (DRA) has emerged as a promising alternative access to minimize RAO risk. A large-scale, international, randomized trial comparing RAO with TRA and DRA is lacking. OBJECTIVES: The aim of this study was to assess the superiority of DRA compared with conventional TRA with respect to forearm RAO. METHODS: DISCO RADIAL (Distal vs Conventional Radial Access) was an international, multicenter, randomized controlled trial in which patients with indications for percutaneous coronary procedure using a 6-F Slender sheath were randomized to DRA or TRA with systematic implementation of best practices to reduce RAO. The primary endpoint was the incidence of forearm RAO assessed by vascular ultrasound at discharge. Secondary endpoints include crossover, hemostasis time, and access site-related complications. RESULTS: Overall, 657 patients underwent TRA, and 650 patients underwent DRA. Forearm RAO did not differ between groups (0.91% vs 0.31%; P = 0.29). Patent hemostasis was achieved in 94.4% of TRA patients. Crossover rates were higher with DRA (3.5% vs 7.4%; P = 0.002), and median hemostasis time was shorter (180 vs 153 minutes; P < 0.001). Radial artery spasm occurred more with DRA (2.7% vs 5.4%; P = 0.015). Overall bleeding events and vascular complications did not differ between groups. CONCLUSIONS: With the implementation of a rigorous hemostasis protocol, DRA and TRA have equally low RAO rates. DRA is associated with a higher crossover rate but a shorter hemostasis time.

Extremity Dysfunction After Large-Bore Radial and Femoral Arterial Access.

Background The use of large-bore (LB) arterial access and guiding catheters has been advocated for complex percutaneous coronary intervention. However, the impact of LB transradial access (TRA) and transfemoral access (TFA) on extremity dysfunction is currently unknown. Methods and Results The predefined substudy of the COLOR (Complex Large-Bore Radial PCI) trial aimed to assess upper and lower-extremity dysfunction after LB radial and femoral access. Upper-extremity function was assessed in LB TRA-treated patients by the Quick Disabilities of the Arm, Shoulder, and Hand questionnaire and lower-extremity function in LB TFA-treated patients by the Lower Extremity Functional Scale questionnaire. Extremity pain and effect of access site complications and risk factors on extremity dysfunction was also analyzed. There were 343 patients who completed analyzable questionnaires. Overall, upper and lower-extremity function did not decrease over time when LB TRA and TFA were used for complex percutaneous coronary intervention, as represented by the median Quick Disabilities of the Arm, Shoulder, and Hand score (6.8 at baseline and 2.1 at follow-up, higher is worse) and Lower Extremity Functional Scale score (56 at baseline and 58 at follow-up, lower is worse). Clinically relevant extremity dysfunction occurred in 6% after TRA and 9% after TFA. A trend for more pronounced upper-limb dysfunction was present in female patients after LB TRA (P=0.05). Lower-extremity pain at discharge was significantly higher in patients with femoral access site complications (P=0.02). Conclusions Following LB TRA and TFA, self-reported upper and lower-limb function did not decrease over time in the majority of patients. Clinically relevant limb dysfunction occurs in a small minority of patients regardless of radial or femoral access. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT03846752.

Impact of opioids on P2Y12 receptor inhibition in patients with ST-elevation myocardial infarction who are pre-treated with crushed ticagrelor: Opioids aNd crushed Ticagrelor In Myocardial infarction Evaluation (ON-TIME 3) trial.

AIMS: Platelet inhibition induced by P2Y12 receptor antagonists in patients with ST-elevation myocardial infarction (STEMI) can be affected by concomitant use of opioids. The aim of this trial was to examine the effect of intravenous (iv) acetaminophen compared with iv fentanyl on P2Y12 receptor inhibition in patients with STEMI. METHODS AND RESULTS: The Opioids aNd crushed Ticagrelor In Myocardial infarction Evaluation (ON-TIME 3) trial randomized 195 STEMI patients who were scheduled to undergo primary percutaneous coronary intervention (PCI) and were pre-treated with crushed ticagrelor to iv acetaminophen (N = 98) or iv fentanyl (N = 97) in the ambulance. The primary endpoint, consisting of the level of platelet reactivity units (PRU) measured immediately after primary PCI, was not significantly different between the study arms [median PRU 104 (IQR 37-215) vs. 175 (63-228), P = 0.18]. However, systemic levels of ticagrelor were significantly higher in the acetaminophen arm at the start of primary PCI [151 ng/mL (32-509) vs. 60 ng/mL (13-206), P = 0.007], immediately after primary PCI [326 ng/mL (94-791) vs. 115 ng/mL (38-326), P = 0.002], and at 1 h after primary PCI [488 ng/mL (281-974) vs. 372 ng/mL (95-635), P = 0.002]. Acetaminophen resulted in the same extent of pain relief when compared with fentanyl [reduction of 3 points on 10-step-pain scale before primary PCI (IQR 1-5)] in both study arms (P = 0.67) and immediately after PCI [reduction of 5 points (3-7); P = 0.96]. CONCLUSION: The iv acetaminophen in comparison with iv fentanyl was not associated with significantly lower platelet reactivity in STEMI patients but resulted in significantly higher ticagrelor plasma levels and was effective in pain relief.

Distal versus conventional radial access for coronary angiography and intervention: Design and rationale of DISCO RADIAL study.

BACKGROUND: Transradial access (TRA) has become the default access method for coronary diagnostic and interventional procedures. As compared to transfemoral access, TRA has been shown to be safer, cost-effective and more patient-friendly. Radial artery occlusion (RAO) represents the most frequent complication of TRA, and precludes future coronary procedures through the radial artery, the use of the radial artery as a conduit for coronary artery bypass grafting or as arteriovenous fistula for patients on hemodialysis. Recently, distal radial access (DRA) has emerged as a promising alternative to TRA, yielding potential for minimizing the risk of RAO. However, an international multicenter randomized comparison between DRA, and conventional TRA with respect to the rate of RAO is still lacking. TRIAL DESIGN: DISCO RADIAL is a prospective, multicenter, open-label, randomized, controlled, superiority trial. A total of 1300 eligible patients will be randomly allocated to undergo coronary angiography and/or percutaneous coronary intervention (PCI) through DRA or TRA using the 6 Fr Glidesheath Slender sheath introducer. Extended experience with both TRA and DRA is required for operators' eligibility and optimal evidence-based best practice to reduce RAO systematically implemented by protocol. The primary endpoint is the incidence of forearm RAO assessed by vascular ultrasound at discharge. Several important secondary endpoints will also be assessed, including access-site cross-over, hemostasis time, and access-site related complications. SUMMARY: The DISCO RADIAL trial will provide the first large-scale multicenter randomized evidence comparing DRA to TRA in patients scheduled for coronary angiography or PCI with respect to the incidence of RAO at discharge.

Left ventricular function, strain, and infarct characteristics in patients with transient ST-segment elevation myocardial infarction compared to ST-segment and non-ST-segment elevation myocardial infarctions.

AIMS: This study aims to explore cardiovascular magnetic resonance (CMR)-derived left ventricular (LV) function, strain, and infarct size characteristics in patients with transient ST-segment elevation myocardial infarction (TSTEMI) compared to patients with ST-segment and non-ST-segment elevation myocardial infarctions (STEMI and NSTEMI, respectively). METHODS AND RESULTS: In total, 407 patients were enrolled in this multicentre observational prospective cohort study. All patients underwent CMR examination 2-8 days after the index event. CMR cine imaging was performed for functional assessment and late gadolinium enhancement to determine infarct size and identify microvascular obstruction (MVO). TSTEMI patients demonstrated the highest LV ejection fraction and the most preserved global LV strain (longitudinal, circumferential, and radial) across the three groups (overall P ≤ 0.001). The CMR-defined infarction was less frequently observed in TSTEMI than in STEMI patients [77 (65%) vs. 124 (98%), P < 0.001] but was comparable with NSTEMI patients [77 (65%) vs. 66 (70%), P = 0.44]. A remarkably smaller infarct size was seen in TSTEMI compared to STEMI patients [1.4 g (0.0-3.9) vs. 13.5 g (5.3-26.8), P < 0.001], whereas infarct size was not significantly different from that in NSTEMI patients [1.4 g (0.0-3.9) vs. 2.1 g (0.0-8.6), P = 0.06]. Whilst the presence of MVO was less frequent in TSTEMI compared to STEMI patients [5 (4%) vs. 53 (31%), P < 0.001], no significant difference was seen compared to NSTEMI patients [5 (4%) vs. 5 (5%), P = 0.72]. CONCLUSION: TSTEMI yielded favourable cardiac LV function, strain, and infarct-related scar mass compared to STEMI and NSTEMI. LV function and infarct characteristics of TSTEMI tend to be more similar to NSTEMI than STEMI.

Sex Differences in Platelet Reactivity in Patients With ST-Elevation Myocardial Infarction: A Sub-Analysis of the ON-TIME 3 Trial.

Background: Fast and adequate platelet inhibition is one of the cornerstones in the treatment of patients with ST-elevation myocardial infarction (STEMI). The aim of this analysis is to examine sex differences in platelet inhibition in the acute treatment of STEMI patients. Methods: Platelet reactivity units (PRU) and ticagrelor plasma concentrations of all patients in the ON-TIME 3 were compared according to sex. All patients were pre-treated with crushed ticagrelor, aspirin and heparin. Both univariable and multivariable analyses were performed. Results: In this sub-analysis of the ON-TIME 3 trial, 195 STEMI patients, of which 58 female patients (29.7%) and 137 male patients (70.3%), were analyzed. PRU-values immediately post-PCI were not different in females [median 135 (IQR 47-228)] compared to males [160 (IQR 40-219), P = 0.92]. Ticagrelor plasma concentrations were higher in the females at the start of primary PCI [141 ng/mL (IQR 25-491) vs. 76 ng/mL (IQR 15-245), P = 0.049] and at 6 hours post-primary PCI [495 ng/mL (IQR 283-661) vs. 321 ng/mL (IQR 196-537), P = 0.001] compared to males. However, immediately post-primary PCI and at 1-hour post-primary PCI no significant differences in ticagrelor concentrations were seen between sexes. In multivariable analysis, sex was significantly associated with ticagrelor concentration (P = 0.04), but not with PRU (P = 0.93). Conclusion: Effective platelet inhibition reached by crushed ticagrelor in STEMI patients was similar in both sexes. Females had similar or even higher ticagrelor plasma concentrations up to 6 hours post-primary PCI compared with males.