Cardiovascular Magnetic Resonance Before Invasive Coronary Angiography in Suspected Non-ST-Segment Elevation Myocardial Infarction.

BACKGROUND: In suspected non-ST-segment elevation myocardial infarction (NSTEMI), this presumed diagnosis may not hold true in all cases, particularly in patients with nonobstructive coronary arteries (NOCA). Additionally, in multivessel coronary artery disease, the presumed infarct-related artery may be incorrect. OBJECTIVES: This study sought to assess the diagnostic utility of cardiac magnetic resonance (CMR) before invasive coronary angiogram (ICA) in suspected NSTEMI. METHODS: A total of 100 consecutive stable patients with suspected acute NSTEMI (70% male, age 62 ± 11 years) prospectively underwent CMR pre-ICA to assess cardiac function (cine), edema (T2-weighted imaging, T1 mapping), and necrosis/scar (late gadolinium enhancement). CMR images were interpreted blinded to ICA findings. The clinical care and ICA teams were blinded to CMR findings until post-ICA. RESULTS: Early CMR (median 33 hours postadmission and 4 hours pre-ICA) confirmed only 52% (52 of 100) of patients had subendocardial infarction, 15% transmural infarction, 18% nonischemic pathologies (myocarditis, Takotsubo and other forms of cardiomyopathies), and 11% normal CMR; 4% were nondiagnostic. Subanalyses according to ICA findings showed that, in patients with obstructive coronary artery disease (73 of 100), CMR confirmed only 84% (61 of 73) had MI, 10% (7 of 73) nonischemic pathologies, and 5% (4 of 73) normal. In patients with NOCA (27 of 100), CMR found MI in only 22% (6 of 27 true MI with NOCA), and reclassified the presumed diagnosis of NSTEMI in 67% (18 of 27: 11 nonischemic pathologies, 7 normal). In patients with CMR-MI and obstructive coronary artery disease (61 of 100), CMR identified a different infarct-related artery in 11% (7 of 61). CONCLUSIONS: In patients presenting with suspected NSTEMI, a CMR-first strategy identified MI in 67%, nonischemic pathologies in 18%, and normal findings in 11%. Accordingly, CMR has the potential to affect at least 50% of all patients by reclassifying their diagnosis or altering their potential management.

Treatment and Care of Patients with ST-Segment Elevation Myocardial Infarction-What Challenges Remain after Three Decades of Primary Percutaneous Coronary Intervention?

Primary percutaneous coronary intervention (pPCI) has revolutionized the prognosis of ST-segment elevation myocardial infarction (STEMI) and is the gold standard treatment. As a result of its success, the number of pPCI centres has expanded worldwide. Despite decades of advancements, clinical outcomes in STEMI patients have plateaued. Out-of-hospital cardiac arrest and cardiogenic shock remain a major cause of high in-hospital mortality, whilst the growing burden of heart failure in long-term STEMI survivors presents a growing problem. Many elements aiming to optimize STEMI treatment are still subject to debate or lack sufficient evidence. This review provides an overview of the most contentious current issues in pPCI in STEMI patients, with an emphasis on unresolved questions and persistent challenges.

Percutaneous coronary intervention for bifurcation coronary lesions using optimised angiographic guidance: the 18th consensus document from the European Bifurcation Club.

The 2023 European Bifurcation Club (EBC) meeting took place in Warsaw in October, and the latest evidence for the use of intravascular ultrasound (IVUS) and optical coherence tomography (OCT) to optimise percutaneous coronary interventions (PCI) on coronary bifurcation lesions (CBLs) was a major focus. The topic generated deep discussions and general appraisal on the potential benefits of IVUS and OCT in PCI procedures. Nevertheless, despite an increasing recognition of IVUS and OCT capabilities and their recognised central role for guidance in complex CBL and left main PCI, it is expected that angiography will continue to be the primary guidance modality for CBL PCI, principally due to educational and economic barriers. Mindful of the restricted access/adoption of intracoronary imaging for CBL PCI, the EBC board decided to review and describe a series of tips and tricks which can help to optimise angiography-guided PCI for CBLs. The identified key points for achieving an optimal angiography-guided PCI include a thorough analysis of pre-PCI images (computed tomography angiography, multiple angiographic views, quantitative coronary angiography vessel estimation), a systematic application of the technical steps suggested for a given selected technique, an intraprocedural or post-PCI use of stent enhancement and a low threshold for bailout use of intravascular imaging.

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.

Pressure-Controlled Intermittent Coronary Sinus Occlusion (PiCSO) in Acute Myocardial Infarction: The PiCSO-AMI-I Trial.

BACKGROUND: Primary percutaneous coronary intervention (pPCI) has improved clinical outcomes in patients with ST-segment-elevation myocardial infarction. However, as many as 50% of patients still have suboptimal myocardial reperfusion and experience extensive myocardial necrosis. The PiCSO-AMI-I trial (Pressure-Controlled Intermittent Coronary Sinus Occlusion-Acute Myocardial Infarction-I) evaluated whether PiCSO therapy can further reduce myocardial infarct size (IS) in patients undergoing pPCI. METHODS: Patients with anterior ST-segment-elevation myocardial infarction and Thrombolysis in Myocardial Infarction flow 0-1 were randomized at 16 European centers to PiCSO-assisted pPCI or conventional pPCI. The PiCSO Impulse Catheter (8Fr balloon-tipped catheter) was inserted via femoral venous access after antegrade flow restoration of the culprit vessel and before proceeding with stenting. The primary end point was the difference in IS (expressed as a percentage of left ventricular mass) at 5 days by cardiac magnetic resonance. Secondary end points were the extent of microvascular obstruction and intramyocardial hemorrhage at 5 days and IS at 6 months. RESULTS: Among 145 randomized patients, 72 received PiCSO-assisted pPCI and 73 conventional pPCI. No differences were observed in IS at 5 days (27.2%±12.4% versus 28.3%±11.45%; P=0.59) and 6 months (19.2%±10.1% versus 18.8%±7.7%; P=0.83), nor were differences between PiCSO-treated and control patients noted in terms of the occurrence of microvascular obstruction (67.2% versus 64.6%; P=0.85) or intramyocardial hemorrhage (55.7% versus 60%; P=0.72). The study was prematurely discontinued by the sponsor with no further clinical follow-up beyond 6 months. However, up to 6 months of PiCSO use appeared safe with no device-related adverse events. CONCLUSIONS: In this prematurely discontinued randomized trial, PiCSO therapy as an adjunct to pPCI did not reduce IS when compared with conventional pPCI in patients with anterior ST-segment-elevation myocardial infarction. PiCSO use was associated with increased procedural time and contrast but no increase in adverse events up to 6 months. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03625869.

Comparison of troponin and natriuretic peptides in Takotsubo syndrome and acute coronary syndrome: a meta-analysis.

OBJECTIVE: Takotsubo syndrome (TTS) is an acute heart failure syndrome which resembles acute coronary syndrome (ACS) at presentation. Differentiation requires coronary angiography, but where this does not occur immediately, cardiac biomarkers may provide additional utility. We performed a meta-analysis to compare troponin and natriuretic peptides (NPs) in TTS and ACS to determine if differences in biomarker profile can aid diagnosis. METHODS: We searched five literature databases for studies reporting NPs (Brain NP (BNP)/NT-pro-BNP) or troponin I/T in TTS and ACS, identifying 28 studies for troponin/NPs (5618 and 1145 patients, respectively). RESULTS: Troponin was significantly lower in TTS than ACS (standardised mean difference (SMD) -0.86; 95% CI, -1.08 to -0.64; p<0.00001), with an absolute difference of 75 times the upper limit of normal (×ULN) higher in ACS than TTS. Conversely, NPs were significantly higher in TTS (SMD 0.62; 95% CI, 0.44 to 0.80; p<0.00001) and 5.8×ULN greater absolutely. Area under the curve (AUC) for troponin in ACS versus TTS was 0.82 (95% CI, 0.70 to 0.93), and 0.92 (95% CI, 0.80 to 1.00) for ST-segment elevation myocardial infarction versus TTS. For NPs, AUC was 0.69 (95% CI, 0.48 to 0.89). Combination of troponin and NPs with logistic regression did not improve AUC. Recursive Partitioning and Regression Tree analysis calculated a troponin threshold ≥26×ULN that identified 95% cases as ACS where and specificity for ACS were 85.71% and 53.57%, respectively, with 94.32% positive predictive value and 29.40% negative predictive value. CONCLUSIONS: Troponin is lower and NPs higher in TTS versus ACS. Troponin had greater power than NPs at discriminating TTS and ACS, and with troponin ≥26×ULN patients are far more likely to have ACS.

Comparison of bolus versus continuous thermodilution derived indices of microvascular dysfunction in revascularized coronary syndromes.

Background: The assessment of coronary microvascular dysfunction (CMD) using invasive methods is a field of growing interest, however the preferred method remains debated. Bolus and continuous thermodilution are commonly used methods, but weak agreement has been observed in patients with angina with non-obstructive coronary arteries (ANOCA). This study examined their agreement in revascularized acute coronary syndromes (ACS) and chronic coronary syndromes (CCS) patients. Objective: To compare bolus thermodilution and continuous thermodilution indices of CMD in revascularized ACS and CCS patients and assess their diagnostic agreement at pre-defined cut-off points. Methods: Patients from two centers underwent paired bolus and continuous thermodilution assessments after revascularization. CMD indices were compared between the two methods and their agreements at binary cut-off points were assessed. Results: Ninety-six patients and 116 vessels were included. The mean age was 64 ± 11 years, and 20 (21 %) were female. Overall, weak correlations were observed between the Index of Microcirculatory Resistance (IMR) and continuous thermodilution microvascular resistance (Rµ) (rho = 0.30p = 0.001). The median coronary flow reserve (CFR) from continuous thermodilution (CFRcont) and bolus thermodilution (CFRbolus) were 2.19 (1.76-2.67) and 2.55 (1.50-3.58), respectively (p < 0.001). Weak correlation and agreement were observed between CFRcont and CFRbolus (rho = 0.37, p < 0.001, ICC 0.228 [0.055-0.389]). When assessed at CFR cut-off values of 2.0 and 2.5, the methods disagreed in 41 (35 %) and 45 (39 %) of cases, respectively. Conclusions: There is a significant difference and weak agreement between bolus and continuous thermodilution-derived indices, which must be considered when diagnosing CMD in ACS and CCS patients.

Incidence, Predictors, and Impact of Hospital Readmission After Revascularization for Left Main Coronary Disease.

BACKGROUND: The frequency of and relationship between hospital readmissions and outcomes after revascularization for left main coronary artery disease (LMCAD) are unknown. OBJECTIVES: The purpose of this study was to study the incidence, predictors, and clinical impact of readmissions following percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) for LMCAD. METHODS: In the EXCEL (XIENCE Versus Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization) trial, 1,905 patients with LMCAD were randomized to PCI vs CABG. The cumulative incidence of readmissions was analyzed with multivariable Anderson-Gill and joint frailty models to account for recurrent events and the competing risk of death. The impact of readmission on subsequent mortality within 5-year follow-up was determined in a time-adjusted Cox proportional hazards model. RESULTS: Within 5 years, 1,868 readmissions occurred in 851 of 1,882 (45.2%) hospital survivors (2.2 ± 1.9 per patient with readmission[s], range 1-16), approximately one-half for cardiovascular causes and one-half for noncardiovascular causes (927 [49.6%] and 941 [50.4%], respectively). One or more readmissions occurred in 463 of 942 (48.6%) PCI patients vs 388 of 940 (41.8%) CABG patients (P = 0.003). After multivariable adjustment, PCI remained an independent predictor of readmission (adjusted HR: 1.22; 95% CI: 1.10-1.35; P < 0.0001), along with female sex, comorbidities, and the extent of CAD. Readmission was independently associated with subsequent all-cause death, with interaction testing indicating a higher risk after PCI than CABG (adjusted HR: 5.72; 95% CI: 3.42-9.55 vs adjusted HR: 2.72; 95% CI: 1.64-4.88, respectively; Pint = 0.03). CONCLUSIONS: In the EXCEL trial, readmissions during 5-year follow-up after revascularization for LMCAD were common and more frequent after PCI than CABG. Readmissions were associated with an increased risk of all-cause death, more so after PCI than with CABG.

Angiography-Derived Index of Microcirculatory Resistance to Define the Risk of Early Discharge in STEMI.

BACKGROUND: Patients with ST-segment-elevation myocardial infarction but no coronary microvascular injury are at low risk of early cardiovascular complications (ECC). We aim to assess whether nonhyperemic angiography-derived index of microcirculatory resistance (NH-IMRangio) could be a user-friendly tool to identify patients at low risk of ECC, potentially candidates for expedited care pathway and early hospital discharge. METHODS: Retrospective analysis of 2 independent, international, prospective, observational cohorts included 568 patients with ST-segment-elevation myocardial infarction. NH-IMRangio was calculated based on standard coronary angiographic views with 3-dimensional-modeling and computational analysis of the coronary flow. RESULTS: Overall, ECC (a composite of cardiovascular death, cardiogenic shock, acute heart failure, life-threatening arrhythmias, resuscitated cardiac arrest, left ventricular thrombus, post-ST-segment-elevation myocardial infarction mechanical complications, and rehospitalization for acute heart failure or acute myocardial infarction at 30 days follow-up), occurred in 54 (9.3%) patients. NH-IMRangio was significantly correlated with pressure/thermodilution-based index of microcirculatory resistance (r=0.607; P<0.0001) and demonstrated good accuracy in predicting ECC (area under the curve, 0.766 [95% CI, 0.706-0.827]; P<0.0001). Importantly, ECC occurred more frequently in patients with NH-IMRangio ≥40 units (18.1% versus 1.4%; P<0.0001). At multivariable analysis, NH-IMRangio provided incremental prognostic value to conventional clinical, angiographic, and echocardiographic features (adjusted-odds ratio, 14.861 [95% CI, 5.177-42.661]; P<0.0001). NH-IMRangio<40 units showed an excellent negative predictive value (98.6%) in ruling out ECC. Discharging patients with NH-IMRangio<40 units at 48 hours after admission would reduce the total in-hospital stay by 943 days (median 2 [1-4] days per patient). CONCLUSIONS: NH-IMRangio is a valuable risk-stratification tool in patients with ST-segment-elevation myocardial infarction. NH-IMRangio guided strategies to early discharge may contribute to safely shorten hospital stay, optimizing resources utilization.

Cost-effectiveness of stepwise provisional versus systematic dual stenting strategies in patients with distal bifurcation left main stem lesions: economic analysis of the EBC MAIN trial.

BACKGROUND: In patients with distal bifurcation left main stem lesions requiring intervention, the European Bifurcation Club Left Main Coronary Stent Study trial found a non-significant difference in major adverse cardiac events (MACEs, composite of all-cause death, non-fatal myocardial infarction and target lesion revascularisation) favouring the stepwise provisional strategy, compared with the systematic dual stenting. AIMS: To estimate the 1-year cost-effectiveness of stepwise provisional versus systematic dual stenting strategies. METHODS: Costs in France and the UK, and MACE were calculated in both groups to estimate the incremental cost-effectiveness ratio (ICER). Uncertainty was explored by probabilistic bootstrapping. The analysis was conducted from the perspective of the healthcare provider with a time horizon of 1 year. RESULTS: The cost difference between the two groups was €-755 (€5700 in the stepwise provisional group and €6455 in the systematic dual stenting group, p value<0.01) in France and €-647 (€6728 and €7375, respectively, p value=0.08) in the UK. The point estimates for the ICERs found that stepwise provisional strategy was cost saving and improved outcomes with a probabilistic sensitivity analysis confirming dominance with an 80% probability. CONCLUSION: The stepwise provisional strategy at 1 year is dominant compared with the systematic dual stenting strategy on both economic and clinical outcomes.

Intravascular ultrasound-guided versus angiography-guided percutaneous coronary intervention in unprotected left main coronary artery disease: A systematic review.

BACKGROUND: Significant unprotected left main coronary artery (ULMCA) disease is encountered in approximately 5 % of patients undergoing diagnostic coronary angiography. Intravascular ultrasound (IVUS) overcomes many of the known limitations of angiography and improves outcomes of patients undergoing percutaneous coronary interventions (PCI) in stable or complex coronary artery disease. The aim of this systematic review is to evaluate the evidence on IVUS-guidance versus angiography-guidance in ULMCA PCI, highlighting the chronological frequencies of event rates in line with the maturation of PCI technique and devices over time. METHODS: A comprehensive systematic search in Medline was performed to identify all studies that had assessed the effect of IVUS-guided versus angiography-guided ULMCA PCI on various primary and secondary endpoints. RESULTS: Seventeen studies (2 randomized, 10 non-randomized and 5 meta-analyses) were included in this systematic review. CONCLUSIONS: This systematic review on IVUS-guided versus angiography-guided PCI in patients with significant ULMCA disease strongly supports the hypothesis that IVUS-guided PCI is associated with a significant reduction in major adverse cardiac events composites, all-cause death, cardiac death, myocardial infarction and stent thrombosis. Ongoing, adequately powered trials will contribute significantly to the level of evidence.

Stratification of acute myocardial and endothelial cell injury, salvage index and final infarct size by systematic microRNA profiling in acute ST-elevation myocardial infarction.

AIM: Acute injury and subsequent remodelling responses to ST-segment elevation myocardial infarction (STEMI) are major determinants of clinical outcome. Current imaging and plasma biomarkers provide delayed readouts of myocardial injury and recovery. Here, we sought to systematically characterize all microRNAs (miRs) released during the acute phase of STEMI and relate miR release to magnetic resonance imaging (MRI) findings to predict acute and late responses to STEMI, from a single early blood sample. METHODS AND RESULTS: miRs were quantified in blood samples obtained from patients after primary PCI (PPCI) for STEMI. Cardiac MRI (cMRI) was performed to quantify myocardial edema, infarct size and salvage index. Regression models were constructed to predict these outcomes measures, which were then tested with a validation cohort. Transcoronary miR release was quantified from paired measurements of coronary artery and coronary sinus samples. A cell culture model was used to identify endothelial cell-derived miRs.A total of 72 patients undergoing PPCI for acute STEMI underwent miR analysis and cMRI. About >200 miRs were detectable in plasma after STEMI, from which 128 miRs were selected for quantification in all patients. Known myocardial miRs demonstrated a linear correlation with troponin release, and these increased across the transcoronary gradient. We identified novel miRs associated with microvascular injury and myocardial salvage. Regression models were constructed using a training cohort, then tested in a validation cohort, and predicted myocardial oedema, infarct size and salvage index. CONCLUSION: Analysis of miR release after STEMI identifies biomarkers that predict both acute and late outcomes after STEMI. A novel miR-based biomarker score enables the estimation of area at risk, late infarct size and salvage index from a single blood sample 6 hours after PPCI, providing a simple and rapid alternative to serial cMRI characterization of STEMI outcome.

Very early invasive strategy in higher risk non-ST-elevation acute coronary syndrome: the RAPID NSTEMI trial.

OBJECTIVE: To investigate whether a very early invasive strategy (IS)±revascularisation improves clinical outcomes compared with standard care IS in higher risk patients with non-ST-elevation acute coronary syndrome (NSTE-ACS). METHODS: Multicentre, randomised, controlled, pragmatic strategy trial of higher risk patients with NSTE-ACS, defined by Global Registry of Acute Coronary Events 2.0 score of ≥118, or ≥90 with at least one additional high-risk feature. Participants were randomly assigned to very early IS±revascularisation (<90 min from randomisation) or standard care IS±revascularisation (<72 hours). The primary outcome was a composite of all-cause mortality, new myocardial infarction or hospitalisation for heart failure at 12 months. RESULTS: The trial was discontinued early by the funder due to slow recruitment during the COVID-19 pandemic. 425 patients were randomised, of whom 413 underwent an IS: 204 to very early IS (median time from randomisation: 1.5 hours (IQR: 0.9-2.0)) and 209 to standard care IS (median: 44.0 hours (IQR: 22.9-72.6)). At 12 months, there was no significant difference in the primary outcome between the early IS (5.9%) and standard IS (6.7%) groups (OR 0.93, 95% CI 0.42 to 2.09; p=0.86). The incidence of stroke and major bleeding was similar. The length of hospital stay was reduced with a very early IS (3.9 days (SD 6.5) vs 6.3 days (SD 7.6), p<0.01). CONCLUSIONS: A strategy of very early IS did not improve clinical outcomes compared with a standard care IS in higher risk patients with NSTE-ACS. However, the primary outcome rate was low and the trial was underpowered to detect such a difference. TRIAL REGISTRATION NUMBER: NCT03707314.

The effect of immunomodulatory drugs on aortic stenosis: a Mendelian randomisation analysis.

There are currently no approved pharmacological treatment options for aortic stenosis (AS), and there are limited identified drug targets for this chronic condition. It remains unclear whether inflammation plays a role in AS pathogenesis and whether immunomodulation could become a therapeutic target. We evaluated the potentially causal association between inflammation and AS by investigating the genetically proxied effects of tocilizumab (IL6 receptor, IL6R, inhibitor), canakinumab (IL1ß inhibitor) and colchicine (ß-tubulin inhibitor) through a Mendelian randomisation (MR) approach. Genetic proxies for these drugs were identified as single nucleotide polymorphisms (SNPs) in the gene, enhancer or promoter regions of IL6R, IL1ß or ß-tubulin gene isoforms, respectively, that were significantly associated with serum C-reactive protein (CRP) in a large European genome-wide association study (GWAS; 575,531 participants). These were paired with summary statistics from a large GWAS of AS in European patients (653,867 participants) to then perform primary inverse-variance weighted random effect and sensitivity MR analyses for each exposure. This analysis showed that genetically proxied tocilizumab was associated with reduced risk of AS (OR 0.56, 95% CI 0.45-0.70 per unit decrease in genetically predicted log-transformed CRP). Genetically proxied canakinumab was not associated with risk of AS (OR 0.80, 95% CI 0.51-1.26), and only one suitable SNP was identified to proxy the effect of colchicine (OR 34.37, 95% CI 1.99-592.89). The finding that genetically proxied tocilizumab was associated with reduced risk of AS is concordant with an inflammatory hypothesis of AS pathogenesis. Inhibition of IL6R may be a promising therapeutic target for AS management.

Ivabradine in the Prevention, and Reduction in Size, of Perioperative Myocardial Injury in Patients Undergoing Orthopedic Surgery for Acute Fracture.

BACKGROUND: Perioperative myocardial injury is common after major noncardiac surgery and is associated with adverse outcomes. This study investigated the use of ivabradine in patients undergoing urgent surgery for fracture. METHODS AND RESULTS: This was a prospective, double-blind, placebo-controlled, randomized clinical trial. Participants were enrolled 1:1 into ivabradine or placebo arm, and study drug was commenced before operation and continued for 7 days or until discharge. High-sensitivity troponin I was measured daily using Abbott Alinity analyzer and assay, and heart rate data were obtained using continuous Holter monitoring. A total of 199 patients underwent acute orthopedic surgery, 98 in the ivabradine group and 101 in the placebo group. The mean age was 78.7 years (range, 77.5-79.9 years), with 68% women. The average heart rate was 5 to 11 beats per minute lower in the ivabradine group compared with the placebo group at all time points (P<0.001 for all). There was no statistically significant difference between the ivabradine and placebo groups in the number of patients who had perioperative myocardial injury: 28.6% versus 31.6% (P=0.71). In patients with perioperative myocardial injury, average peak troponin was 168.8 ng/L (±431.2 ng/L) in the ivabradine group and 2094.5 ng/L (±7201.9 ng/L) in the placebo group (P=0.16). There was no statistically significant difference between groups in 30-day mortality, blood pressure, stroke, or major adverse cardiovascular event. CONCLUSIONS: Starting ivabradine preoperatively in elderly patients requiring acute surgery for fracture did not result in a statistically significant difference in the incidence of perioperative myocardial injury. There was no statistically significant difference in morbidity, mortality, or adverse events between treatment groups. REGISTRATION: URL: https://www.anzctr.org.au/; Unique identifier: ACTRN12616001634460p.