Frequency of periprocedural myocardial injury and infarction stratified by cardiac troponin I and cardiac troponin T

BACKGROUND

There are different definitions of periprocedural myocardial infarction (PPMI) both in terms of thresholds for cardiac biomarkers and the ancillary criteria for myocardial ischemia. Cardiac Troponin I (cTnI) and cardiac Troponin T (cTnT) are used interchangeably to diagnose PPMI.

OBJECTIVES

This study evaluated the frequency of periprocedural myocardial injury and infarction as defined by the Society of Cardiovascular Angiography & Interventions (SCAI), the Academic Research Consortium-2 (ARC-2), and the 4th Universal definition of MI (4UDMI) stratified using cTnT versus cTnI, among patients with chronic coronary syndrome (CCS) and unstable angina.

RESULTS

Among 830 patients, PPMI rates according to the SCAI, ARC2 and 4UDMI criteria were 4.34 %, 2.05 %, and 4.94 % respectively, with higher rates seen for all definitions when using cTnI versus cTnT (SCAI: 9.84 % vs. 1.91 %, p < 0.001; ARC 2: 3.15 % vs. 1.56 %, p = 0.136; and 4UDMI 5.91 % vs. 4.51 %, p = 0.391). Minor and major periprocedural myocardial injury was respectively observed in 58.31 % and 27.10 % of patients, with rates of both significantly higher when using cTnI versus cTnT (Minor: 69.29 % vs. 53.47 %, p < 0.001, Major: 49.21 % vs. 17.36 %, p < 0.001).

CONCLUSIONS

Among patients with CCS and unstable angina, PPMIs defined by SCAI occurred more frequently when using cTnI as opposed to cTnT, whereas the type of troponin had no impact on the incidence of PPMIs according to the ARC-2 and 4UDMI.

Achievement of Target Gain Larger than Unity in an Inertial Fusion Experiment

On December 5, 2022, an indirect drive fusion implosion on the National Ignition Facility (NIF) achieved a target gain G_{target} of 1.5. This is the first laboratory demonstration of exceeding "scientific breakeven" (or G_{target}>1) where 2.05 MJ of 351 nm laser light produced 3.1 MJ of total fusion yield, a result which significantly exceeds the Lawson criterion for fusion ignition as reported in a previous NIF implosion [H. Abu-Shawareb et al. (Indirect Drive ICF Collaboration), Phys. Rev. Lett. 129, 075001 (2022)PRLTAO0031-900710.1103/PhysRevLett.129.075001]. This achievement is the culmination of more than five decades of research and gives proof that laboratory fusion, based on fundamental physics principles, is possible. This Letter reports on the target, laser, design, and experimental advancements that led to this result.

Definitions and Standardized Endpoints for Treatment of Coronary Bifurcations

The Bifurcation Academic Research Consortium (Bif-ARC) project originated from the need to overcome the paucity of standardization and comparability between studies involving bifurcation coronary lesions. This document is the result of a collaborative effort between academic research organizations and the most renowned interventional cardiology societies focused on bifurcation lesions in Europe, the United States, and Asia. This consensus provides standardized definitions for bifurcation lesions; the criteria to judge the side branch relevance; the procedural, mechanistic, and clinical endpoints for every type of bifurcation study; and the follow-up methods. Considering the complexity of bifurcation lesions and their evaluation, detailed instructions and technical aspects for site and core laboratory analysis of bifurcation lesions are also reported. The recommendations included within this consensus will facilitate pooled analyses and the effective comparison of data in the future, improving the clinical relevance of trials in bifurcation lesions, and the quality of care in this subset of patients.

Associations of Inflammatory Biomarkers With the Risk of Morbidity and Mortality After Cardiac Surgery: A Systematic Review and Meta-analysis

BACKGROUND

Although inflammatory biomarkers have been associated with cardiovascular events in nonsurgical settings, these associations have not been systematically addressed in patients undergoing cardiac surgery. This review aimed to evaluate the relationships of inflammatory markers with mortality and adverse cardiovascular events in patients undergoing cardiac surgery.

METHODS

Medline, Embase, and Central databases were systematically searched for studies reporting pre- or postoperative levels of inflammatory biomarkers in patients undergoing cardiac surgery. Outcomes of interest were postoperative mortality, nonfatal myocardial infarction, stroke, congestive heart failure, and major adverse cardiovascular events (MACE). Studies reporting multivariable adjusted risk estimates were included. Risk estimates were pooled with the use of random-effects models and reported as summary odds ratios (ORs).

RESULTS

Among 14,465 citations identified, 29 studies including 29,401 participants met the eligibility criteria. The average follow-up time after surgery was 31 months. Preoperative C-reactive protein (CRP) levels were associated with an increased risk of all-cause mortality (OR 1.88, 95% CI 1.60-2.20; I2 = 19%; 11 studies) and MACE (OR 1.73, 95% CI 1.34-2.24; I2 = 0%; 3 studies). CRP levels measured on postoperative day 6 (OR 7.4, 95% CI 2.90-18.88, 1 study) and day 10 (OR 11.8, 95% CI 3.50-39.78, 1 study) were associated with a higher risk of all-cause mortality. Less, but overall similar, information was available for other inflammatory biomarkers.

CONCLUSIONS

In this large meta-analysis, inflammatory biomarkers measured before or after cardiac surgery were associated with mortality and adverse cardiovascular outcomes in patients undergoing cardiac surgery.

Atorvastatin versus Placebo in ICU Patients with COVID-19: Ninety-day Results of the INSPIRATION-S Trial

BACKGROUNDS

In the INSPIRATION-S trial, atorvastatin versus placebo was associated with a non-significant 16% reduction in 30-day composite of venous/arterial thrombosis or death in ICU patients with COVID-19. Thrombo-inflammatory response in COVID-19 may last beyond the first 30 days.

METHODS

This article reports the effects of atorvastatin 20 mg daily versus placebo on 90-day clinical and functional outcomes from INSPIRATION-S, a double-blind multicenter randomized trial of adult ICU patients with COVID-19. The main outcome for this pre-specified study was a composite of adjudicated venous/arterial thrombosis, treatment with extracorporeal membrane oxygenation (ECMO), or all-cause mortality. Functional status was assessed with Post-COVID-19 Functional Scale (PCFS).

RESULTS

In the primary analysis, 587 patients were included (age: 57 (Q1, Q3: 45, 68) years; 44% women). By 90-day follow-up, the main outcome occurred in 96 (33.1%) patients assigned to atorvastatin and 113 (38.0%) assigned to placebo (hazard ratio, HR: 0.80, 95% confidence interval, CI: 0.60-1.05, P=0.11). Atorvastatin in patients who presented within 7 days of symptom onset was associated with reduced 90-day hazard for the main outcome (HR: 0.60, 95% CI: 0.42-0.86, Pinteraction=0.02). Atorvastatin use was associated with improved 90-day functional status, although the upper bound CI crossed 1.0 (ORordinal, 0.64, 95% CI: 0.41 to 1.01, P=0.05).

CONCLUSIONS

Atorvastatin 20 mg compared with placebo did not significantly reduce the 90-day composite of death, treatment with ECMO, or venous/arterial thrombosis. However, the point estimates do not exclude a potential clinically meaningful treatment effect, especially among patients who presented within 7 days of symptom onset. (NCT04486508).

Optical coherence tomography and coronary revascularization: from indication to procedural optimization

Angiography alone is the most commonly used imaging modality for guidance of percutaneous coronary interventions. Angiography is limited, however, by several factors, including that it only portrays a low resolution, two-dimensional outline of the lumen and does not inform on plaque composition and functional stenosis severity. Optical coherence tomography (OCT) is an intracoronary imaging technique that has superior spatial resolution compared to all other imaging modalities. High-resolution imaging of the vascular wall enables precise measurement of vessel wall and luminal dimensions, more accurately informing about the anatomic severity of epicardial stenoses, and also provides input for computational models to assess functional severity. The very high-resolution images also permit plaque characterization that may be informative for prognostication. Moreover, periprocedural imaging provides valuable information to guide lesion preparation, stent implantation and to evaluate acute stent complications for which iterative treatment might reduce the occurrence of major adverse stent events. As such, OCT represent a potential future all-in-one tool that provides the data necessary to establish the indications, procedural planning and optimization, and final evaluation of percutaneous coronary revascularization.

Heterogeneous plaque geometry is associated with major adverse cardiovascular events

Objectives

To determine whether coronary artery plaque-lumen geometry predicts major adverse cardiovascular events (MACE), and incorporating geometric measures enhances risk stratification from intravascular imaging.

Background

Prospective studies show that only a minority of plaques with higher-risk features result in future MACE, indicating the need for more predictive markers of plaque vulnerability. Plaques show heterogeneous structures and plaque-lumen geometry, both of which can promote high plaque structural stress (PSS); however, the relationships between geometric heterogeneity and MACE or PSS are unknown.

Methods

We examined plaque-lumen curvature, irregularity, lumen aspect ratio (LAR), roughness, PSS and their longitudinal heterogeneity (Figure 1A) in 35 non-culprit lesions (NCL) associated with MACE and 66 propensity-matched no-MACE NCL from the PROSPECT (Providing Regional Observations to Study Predictors of Events in the Coronary Tree) study. Causes of heterogeneous geometry and PSS were examined using a separate group of co-registered virtual histology-intravascular ultrasound (VH-IVUS) and optical coherence tomography (OCT) images (n=53 plaques).

Results

Plaque geometry heterogeneity indices (HI) were increased in NCL MACE vs. no-MACE lesions across the whole plaque and peri-minimal luminal area (MLA) segments (HI curvature: p=0.002; HI irregularity: p&lt;0.001; HI LAR: p=0.001; HI roughness: p=0.002). Peri-MLA HI roughness was an independent predictor of future MACE (hazard ratio: 3.69, p&lt;0.001) (Figure 1B). Inclusion of HI roughness improved identification of NCLs leading to MACE in VH-defined thin-cap fibroatheromas (VH-TCFA, p=0.005), MLA ≤4mm2 (p=0.001), and plaque burden (PB) ≥70% (p&lt;0.001) (Figure 1C–E), and further improved the ability of PSS to identify MACE NCLs in VH-TCFA (p=0.041), MLA ≤4mm2 (p=0.033), and PB ≥70% (p&lt;0.001). HI roughness generally corresponded with HI PSS, but was also increased at sites of local calcification and multilayering.

Conclusions

Plaque-lumen geometric heterogeneity is increased across whole plaque and peri-MLA segments of NCLs causing MACE. Inclusion of geometric heterogeneity may improve the ability of intravascular imaging to predict MACE.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): British Heart Foundation

Lawson Criterion for Ignition Exceeded in an Inertial Fusion Experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion.

Geographical variations in left main coronary artery revascularisation: a prespecified analysis of the EXCEL trial

BACKGROUND

The EXCEL trial reported similar five-year rates of the primary composite outcome of death, myocardial infarction (MI), or stroke after percutaneous coronary intervention (PCI) compared with coronary artery bypass grafting (CABG) for treatment of obstructive left main coronary artery disease (LMCAD).

AIMS

We sought to determine whether these outcomes remained consistent regardless of geography of enrolment.

METHODS

We performed a prespecified subgroup analysis based on regional enrolment.

RESULTS

Among 1,905 patients randomised to PCI (n=948) or CABG (n=957), 1,075 (56.4%) were recruited at 52 European Union (EU) centres, and 752 (39.5%) were recruited at 67 North American (NA) centres. EU versus NA patients varied according to numerous baseline demographics, anatomy, pharmacotherapy and procedural characteristics. Nonetheless, the relative rates of the primary endpoint after PCI versus CABG were consistent across EU versus NA centres at 30 days and 5 years. However, NA participants had substantially higher late rates of ischaemia-driven revascularisation (IDR) after PCI, driven predominantly by the need for greater target vessel and lesion revascularisation. This culminated in a significant difference in the relative risk of the secondary composite outcome of death, MI, stroke, or IDR at 5 years (p_interaction=0.02).

CONCLUSIONS

In the EXCEL trial, the relative risks for the 30-day and five-year primary composite outcome of death, MI or stroke after PCI versus CABG were consistent irrespective of geography. However, five-year rates of IDR after PCI were significantly higher in NA centres, a finding the Heart Team and patients should consider when making treatment decisions. ClinicalTrials.gov identifier: NCT01205776.

Optimal dual antiplatelet therapy duration for bioresorbable scaffolds: an individual patient data pooled analysis of the ABSORB trials

BACKGROUND

Compared with everolimus-eluting metallic stents, the Absorb bioresorbable scaffold (BRS) results in increased rates of myocardial infarction (MI) and scaffold thrombosis (ST) during its three-year bioresorption phase. It is unknown whether prolonged dual antiplatelet therapy (DAPT) duration might decrease the risk of ischaemic events.

AIMS

We sought to evaluate the impact of DAPT duration on ischaemic and bleeding outcomes following BRS implantation.

METHODS

We conducted an individual patient data pooled analysis from four ABSORB randomised trials and one prospective ABSORB registry. Study endpoints were MI, ST, bleeding, and death up to three-year follow-up. Propensity score-adjusted Cox regression analysis was used to account for baseline differences related to DAPT duration.

RESULTS

The five ABSORB studies included 2,973 patients. DAPT use was 91.7%, 53.2%, and 48.0% at 1, 2, and 3 years, respectively. DAPT use within the first year after BRS implantation was associated with markedly lower risks of MI (adjusted hazard ratio [aHR] 0.17, 95% CI: 0.10-0.32; p<0.0001) and ST (aHR 0.08, 95% CI: 0.03-0.19; p<0.0001). Conversely, DAPT use between 1 and 3 years did not significantly affect the risk of MI (aHR 1.04, 95% CI: 0.70-1.55; p=0.84) or ST (aHR 0.86, 95% CI: 0.42-1.75; p=0.67). DAPT did not have major effects upon bleeding or death in either period.

CONCLUSIONS

DAPT use during the first year after BRS implantation was strongly associated with lower risks of ST and MI. However, a benefit of ongoing DAPT use between 1 and 3 years after BRS implantation was not apparent.

Impact of left ventricular ejection fraction on clinical outcomes in females undergoing percutaneous coronary intervention with drug-eluting stents

Background

Reduced left ventricular ejection fraction (LVEF) is associated with increased risk of adverse events among patients undergoing percutaneous coronary intervention (PCI). Due to under-enrollment of females in randomized trials, there is limited data on the impact of LVEF on post-PCI outcomes in female patients.

Purpose

To evaluate the impact of varying degrees of LVEF impairment on 3-year outcomes in female patients undergoing PCI with drug-eluting stents (DES).

Methods

We pooled patient-level data of female patients from 26 randomized trials of coronary stents. The study population was stratified into three groups according to the 2016 European Society of Cardiology Heart Failure guidelines: LVEF ≥50% (normal), LVEF 40–49% (mid-range), and LVEF &lt;40% (reduced). The primary outcome was major adverse cardiac events (MACE), a composite of cardiac death, myocardial infarction (MI), or stent thrombosis (ST) at 3-year follow-up. The Kaplan-Meier method was used for time-to-event analyses, with comparative risks being assessed using Cox regression.

Results

Out of 5672 female patients with available LVEF values at baseline, 4427 (78.1%) had normal LVEF, 602 (10.6%) had mid-range LVEF, and 643 (11.3%) had reduced LVEF. Patients with reduced LVEF were older and had a higher prevalence of smoking, prior MI, and multi-vessel disease. There was a stepwise increase in 3-year event rates moving from normal, to mid-range and reduced LVEF (Figure 1). After multivariable adjustment, hazard ratio (HR) for MACE was 1.45 (95% CI: 1.10–1.92) in patients with mid-range LVEF and 2.43 (95% CI: 1.84–3.22) in patients with reduced LVEF (trend p-value &lt;0.0001). The risk of ST was more than doubled in both mid-range LVEF (HR 2.30, 95% CI: 1.30–4.06, p=0.004) and reduced LVEF patients (HR 2.18, 95% CI: 1.11–4.28, p=0.02), as compared with normal LVEF.

Conclusion

The presence of an even mild degree of LVEF impairment confers an increased risk of ischemic events, including ST, among females undergoing PCI with DES.

Funding Acknowledgement

Type of funding sources: None. Figure 1

Comparison between a novel sirolimus-eluting bioresorbable scaffold with everolimus-eluting metallic stent in patients with coronary artery disease: three-year follow-up from the neovas rct study

Background

Previous trials and meta-analyses have demonstrated that risk of adverse clinical events, especially thrombosis and target vessel myocardial infarction is increasing between 1 and 3 years after Bioresorbable Scaffolds (BRS) implantation.

Purpose

We sought to evaluate the long-term clinical outcomes of a novel NeoVas BRS in comparison with cobalt chromium everolimus-eluting stent (EES) following implantation in patients with coronary artery disease by 3-year follow-up results from the NeoVas RCT.

Methods

Overall, 560 patients with a single de novo native coronary artery lesion with reference vessel diameter 2.5–3.75 mm and lesion length ≤20 mm were randomized 1:1 to NeoVas BRS vs. cobalt-chromium everolimus-eluting stents (CoCr-EES). Optical coherence tomography (OCT) and fractional flow reserve (FFR) were both performed in a pre-specified subgroup at 3-year follow-up. Clinical outcomes from NeoVas RCT were analyzed by randomized device (intention to treat) cumulative to 3 years.

Results

Over 3 years, the overall target lesion failure (TLF) rate was 6.9% in the NeoVas group and 6.1% in the CoCr-EES group (HR 1.13, 95% CI 0.59 to 2.18; p=0.71). There was no statistically significant difference of the definite or probable stent thrombosis between the NeoVas group and the CoCr-EES group (1.1% vs. 0.7%, HR 1.51, 95% CI 0.26 to 8.73, p=0.64). In a landmark analysis of TLF, we found no difference in rate of late events from 2 to 3 years between two groups. FFR was not significantly different between the two group at 3 years (NeoVas vs. CoCr-EES, 0.89±0.07 vs. 0.90±0.05). NeoVas was largely absorbed (72.26% ± 13.21%) examined by OCT follow-up. Of 55 patients who finished 3-year absorption analysis, NeoVas was totally absorbed in 4 patients.

Conclusions

At the 3-year follow-up in the Neovas RCT trial, overall TLF rates were comparable between Neovas BRS and CoCr-EES, and adverse event rates relating to device safety were not increased with Neovas BRS compared with CoCr-EES up to 3 years after implantation.

Funding Acknowledgement

Type of funding sources: None.

Global Chronic Total Occlusion Crossing Algorithm: JACC State-of-the-Art Review

The authors developed a global chronic total occlusion crossing algorithm following 10 steps: 1) dual angiography; 2) careful angiographic review focusing on proximal cap morphology, occlusion segment, distal vessel quality, and collateral circulation; 3) approaching proximal cap ambiguity using intravascular ultrasound, retrograde, and move-the-cap techniques; 4) approaching poor distal vessel quality using the retrograde approach and bifurcation at the distal cap by use of a dual-lumen catheter and intravascular ultrasound; 5) feasibility of retrograde crossing through grafts and septal and epicardial collateral vessels; 6) antegrade wiring strategies; 7) retrograde approach; 8) changing strategy when failing to achieve progress; 9) considering performing an investment procedure if crossing attempts fail; and 10) stopping when reaching high radiation or contrast dose or in case of long procedural time, occurrence of a serious complication, operator and patient fatigue, or lack of expertise or equipment. This algorithm can improve outcomes and expand discussion, research, and collaboration.

Outcomes of transcatheter mitral valve repair for secondary mitral regurgitation by severity of left ventricular dysfunction

BACKGROUND

In the COAPT trial, transcatheter mitral valve repair with the MitraClip plus maximally tolerated guideline-directed medical therapy (GDMT) improved clinical outcomes compared with GDMT alone in symptomatic patients with heart failure (HF) and 3+ or 4+ secondary mitral regurgitation (SMR) due to left ventricular (LV) dysfunction.

AIMS

In this COAPT substudy, we sought to evaluate two-year outcomes in HF patients with reduced LV ejection fraction (HFrEF; LVEF ≤40%) versus preserved LVEF (HFpEF; LVEF >40%) and in those with severe (LVEF ≤30%) versus moderate (LVEF >30%) LV dysfunction.

METHODS

The principal effectiveness outcome was the two-year rate of death from any cause or HF hospitalisations (HFH). Subgroup analysis with interaction testing was performed according to baseline LVEF; 472 patients (82.1%) had HFrEF (mean LVEF 28.0%±6.2%; range 12% to 40%) and 103 (17.9%) had HFpEF (mean LVEF 46.6%±4.9%; range 41% to 65%), while 292 (50.7%) had severely depressed LVEF (LVEF ≤30%; mean LVEF 23.9%±3.8%) and 283 (49.3%) had moderately depressed LVEF (LVEF >30%; mean LVEF 39.0%±6.8%).

RESULTS

The two-year rate of death or HFH was 56.7% in patients with HFrEF and 53.4% with HFpEF (HR 1.16, 95% CI: 0.86-1.57, p=0.32). MitraClip reduced the two-year rate of death or HFH in patients with HFrEF (HR 0.50, 95% CI: 0.39-0.65) and HFpEF (HR 0.60, 95% CI: 0.35-1.05), pint=0.55. MitraClip was consistently effective in reducing the individual endpoints of mortality and HFH, improving MR severity, quality of life, and six-minute walk distance in patients with HFrEF, HFpEF, LVEF ≤30%, and LVEF >30%.

CONCLUSIONS

In the COAPT trial, among patients with HF and 3+ or 4+ SMR who remained symptomatic despite maximally tolerated GDMT, the MitraClip was consistently effective in improving survival and health status in patients with severe and moderate LV dysfunction and those with preserved LVEF.

Very late vasomotor responses and gene expression with bioresorbable scaffolds and metallic drug-eluting stents

OBJECTIVES

To investigate the long-term vasomotor response and inflammatory changes in Absorb bioresorbable vascular scaffold (BVS) and metallic drug-eluting stent (DES) implanted artery.

BACKGROUND

Clinical evidence has demonstrated that compared to DES, BVS is associated with higher rates of target lesion failure. However, it is not known whether the higher event rates observed with BVS are related to endothelial dysfunction or inflammation associated with polymer degradation.

METHODS

Ten Absorb BVS and six Xience V DES were randomly implanted in the main coronaries of six nonatherosclerotic swine. At 4-years, vasomotor response was evaluated in vivo by quantitative coronary angiography response to intracoronary infusion of Ach and ex vivo by the biomechanical response to prostaglandin F2-α (PGF2-α), substance P and bradykinin and gene expression analysis.

RESULTS

Absorb BVS implanted arteries showed significantly restored vasoconstrictive responses after Ach compared to in-stent Xience V. The contractility of Absorb BVS treated segments induced by PGF2-α was significantly greater compared to Xience V treated segments and endothelial-dependent vasorelaxation was greater with Absorb BVS compared to Xience V. Gene expression analyses indicated the pro-inflammatory lymphotoxin-beta receptor (LTβR) signaling pathway was significantly upregulated in arteries treated with a metallic stent compared to Absorb BVS treated arterial segments.

CONCLUSIONS

At 4 years, arteries treated with Absorb BVS compared with Xience V, demonstrate significantly greater restoration of vasomotor responses. Genetic analysis suggests mechanobiologic reparation of Absorb BVS treated arteries at 4 years as opposed to Xience V treated vessels.

Asian Pacific Society of Cardiology Consensus Recommendations on the Use of MitraClip for Mitral Regurgitation

Transcatheter mitral valve repair with the MitraClip, a catheter-based percutaneous edge-to-edge repair technique to correct mitral regurgitation (MR), has been demonstrated in Western studies to be an effective and safe MR treatment strategy. However, randomised clinical trial data on its use in Asian-Pacific patients is limited. Hence, the Asian Pacific Society of Cardiology convened an expert panel to review the available literature on MitraClip and to develop consensus recommendations to guide clinicians in the region. The panel developed statements on the use of MitraClip for the management of degenerative MR, functional MR, and other less common indications, such as acute MR, dynamic MR, hypertrophic obstructive cardiomyopathy, and MR after failed surgical repair. Each statement was voted on by each panel member and consensus was reached when 80% of experts voted ‘agree’ or ‘neutral’. This consensus-building process resulted in 10 consensus recommendations to guide general cardiologists in the evaluation and management of patients in whom MitraClip treatment is being contemplated.

Outcomes of optical coherence tomography compared with intravascular ultrasound and with angiography to guide coronary stent implantation: one-year results from the ILUMIEN III: OPTIMIZE PCI trial

AIMS

In the ILUMIEN III trial, among 450 randomised patients with non-complex lesions undergoing percutaneous coronary intervention (PCI), optical coherence tomography (OCT) guidance led to greater stent expansion than angiography guidance, similar minimal stent area compared to both intravascular ultrasound (IVUS) guidance and angiography guidance, and lower rates of uncorrected dissection and malapposition than both IVUS guidance and angiography guidance. Whether these differences impact on clinical outcomes is unknown. The aim of the present study was to report the 12-month clinical follow-up data from the ILUMIEN III study.

METHODS AND RESULTS

OCT-guided PCI, using an external elastic lamina-based protocol, was compared to operator-directed IVUS-guided or angiography-guided PCI. Target lesion failure (TLF) and major adverse cardiovascular events (MACE) at 12 months were adjudicated by a blinded clinical events committee. There were no significant differences in the rates of TLF (2.0% OCT, 3.7% IVUS, 1.4% angiography), MACE (9.8% OCT, 9.1% IVUS, 7.9% angiography), or any of the individual components of these outcomes among the groups. No independent predictors of 12-month stent-related clinical events were identified from final OCT.

CONCLUSIONS

In this underpowered study, OCT-guided PCI of non-complex lesions did not show a statistical difference in clinical outcomes at 12 months compared with IVUS or angiography guidance. An appropriately powered trial, including only complex patients and lesions, is underway to substantiate the potential clinical benefit of OCT-guided PCI.

TRIAL REGISTRATION

NCT02471586.

Optical coherence tomography-guided coronary stent implantation compared to angiography: a multicentre randomised trial in PCI - design and rationale of ILUMIEN IV: OPTIMAL PCI

AIMS

Randomised trials have demonstrated improvement in clinical outcomes with intravascular ultrasound (IVUS)-guided percutaneous coronary intervention (PCI) compared with angiography-guided PCI. The ILUMIEN III trial demonstrated non-inferiority of an optical coherence tomography (OCT)- versus IVUS-guided PCI strategy in achieving similar post-PCI lumen dimensions. ILUMIEN IV is a large-scale, multicentre, randomised trial designed to demonstrate the superiority of OCT- versus angiography-guided stent implantation in patients with high-risk clinical characteristics (diabetes) and/or complex angiographic lesions in achieving larger post-PCI lumen dimensions and improving clinical outcomes.

METHODS AND RESULTS

ILUMIEN IV is a prospective, single-blind clinical investigation that will randomise between 2,490 and 3,656 patients using an adaptive design to OCT-guided versus angiography-guided coronary stent implantation in a 1:1 ratio. The primary endpoints are: (1) post-PCI minimal stent area assessed by OCT in each randomised arm, and (2) target vessel failure, the composite of cardiac death, target vessel myocardial infarction, or ischaemia-driven target vessel revascularisation. Clinical follow-up will continue for up to two years. The trial is currently enrolling, and the principal results are expected in 2022.

CONCLUSIONS

The large-scale ILUMIEN IV randomised controlled trial will evaluate the effectiveness of OCT-guided versus angiography-guided PCI in improving post-PCI lumen dimensions and clinical outcomes in patients with diabetes and/or with complex coronary lesions.

TRIAL REGISTRATION

NCT03507777.

Queensland’s multi-year Wet and Dry periods: implications for grazing enterprises and pasture resources

Year-to-year variability in rainfall has long been recognised as a major issue in managing livestock enterprises across Australia’s grazing lands. Extension products documenting rainfall variability have been developed over the last 30 years and have been keenly sought by producers and their advisors. This paper describes multi-year rainfall variability from 1889 to 2020 and provides the basis for classifying the 131 years of rainfall into 18 discrete Wet (7), Average (2) and Dry (9) periods as presented in the ‘Queensland’s Extended Wet and Dry Periods’ poster. The classification was consistent with: analysis of fluctuations and trends in the long-term time series of reported livestock numbers; drought declarations for government assistance; and documented periods of pasture resource degradation and recovery. Rainfall during the nine Wet and Average periods was +18% above the long-term average annual rainfall (LTAAR), in contrast to the Dry periods with −17% below LTAAR. Wet periods (including Average) were on average 7 years in duration, ranging from 5 to 9 years. Dry periods were on average 8 years in duration and ranged from 5 to 13 years. Detailed analysis of the effects of the El Niño Southern Oscillation (ENSO) phenomenon indicated that: (a) the Wet/Dry periods were dominated by different frequencies and amounts of rainfall in La Niña/El Niño years; (b) rainfall in ENSO neutral years was generally above and below average rainfall for the Wet or Dry periods respectively; (c) the frequency of ENSO year-types was less important than the overall rainfall surplus (or deficit) in La Niña (or El Niño) years within the Wet (or Dry) periods respectively; and (d) the timing of Wet and Dry periods was correlated with indices of quasi-decadal and inter-decadal variability in components (sea surface temperatures and atmospheric pressures) of the global climate system. Climatic risk assessment systems for grazing management at multi-year timescales are yet to be developed.

An online system for calculating and delivering long-term carrying capacity information for Queensland grazing properties. Part 1: background and development

This paper (Part 1) describes the development of a new online system that estimates long-term carrying capacity (LTCC) for grazing properties across Queensland, Australia. High year-to-year and multi-year rainfall variability is a dominating feature of the climate of Queensland’s grazing lands, and poses major challenges for extensive livestock production. The use of LTCC is one approach used by graziers to reduce the impact of rainfall variability on land condition and financial performance. Over the past 30 years, scientists, graziers and their advisors have developed a simple approach to calculating LTCC ((average annual pasture growth × safe pasture utilisation) ÷ annual animal intake). This approach has been successful at a property scale (regional south-west Queensland) and in a wider application through Grazing Land Management (GLM) regional workshops. We have built on these experiences to develop an online system (as described in detail in Part 2; Zhang et al. 2021; this issue) that incorporates the simple LTCC approach with advances in technology and grazing science to provide LTCC information for Queensland grazing properties. Features of the LTCC system are: (1) assimilation of spatial datasets (cadastral data, grazing land types, climate data, remotely-sensed woody vegetation cover); (2) a pasture growth simulation model; (3) land type parameter sets of biophysical attributes; and (4) estimates of safe pasture utilisation. The ‘FORAGE LTCC report’ is a major product of the system, describing individual property information that allows detailed analysis and explanation of the components of the LTCC calculation by land type and land condition. The online system rapidly analyses property spatial data and calculates paddock/property LTCC information. For the 10 months between November 2020 and August 2021, over 4000 grazing property reports have been requested in Queensland, and has proven to be a sound basis for ‘discussion support’ with grazier managers and their advisors.

An online system for calculating and delivering long-term carrying capacity information for Queensland grazing properties. Part 2: modelling and outputs

A combination of field data and models have been used to estimate long-term carrying capacity (LTCC) of domestic livestock in Queensland grazing lands. These methods have been synthesised and coupled with recent developments in science and information technology to provide a fully-automated approach of modelling LTCC through the FORAGE online system. In this study, the GRASP model was used to simulate pasture growth with parameter sets and safe pasture utilisation rates defined for 225 land types across Queensland. Distance to water points was used to assess the accessibility of pastures to livestock. Spatial analysis classified the property into unique areas based on paddock, land type and distance to water points, which estimated pasture growth, pasture utilisation and accessibility at a sub-paddock scale. Thirteen foliage projective cover (FPC) classes were used in modelling the pasture system to deal with the non-linear relationship between tree and grass interactions. As ‘proof of concept’, remotely-sensed individual-date green ground cover data were used to optimise the GRASP model parameters to improve the model performance, and a Monte Carlo analysis provided uncertainty estimates for model outcomes. The framework provides an efficient and standardised method for estimating LTCC. To test the system, LTCCs from 43 ‘benchmark’ properties were compared with simulated LTCCs, and 65% of the modelled LTCCs were within ± 25% of the benchmark LTCCs. Due to uncertainties in model inputs at the property scale and in model simulation, the modelled LTCC should be used as a starting point for further refinement of actual property LTCC.

Side branch FFR after provisional stenting: simplified approach based on OCT frame count

Background/Introduction

Treatment of bifurcation coronary artery lesions remains a major challenge in interventional cardiology. Side branch (SB) stenoses are frequently observed after stent implantation in bifurcation lesions, although angiographically narrowed SBs may not be functionally significant. Fractional flow reserve (FFR), a pressure-derived index of the hemodynamic significance of a coronary artery stenosis, may be useful in determining whether additional intervention is required in jailed SBs. Angiography and intravascular ultrasound (IVUS) derived parameters have showed poor diagnostic accuracy in predicting the functional significance of jailed SBs.

Purpose

The aim of the present study was to use high resolution optical coherence tomography (OCT) imaging to predict functionally significant SB stenoses after provisional stenting defined as SB FFR ≤0.80.

Methods

Seventy-one patients with 71 calcified bifurcation lesions with angiographically intermediate SB stenoses undergoing provisional stenting were enrolled in the prospective study. OCT pullbacks were performed before and after stent placement, and SB FFR was measured after main vessel stenting. SB ostium area (SBOA) was assessed using three-dimensional OCT cut-plane analysis off-line. In addition, we developed a simplified approach to SB ostium assessment based on SB ostium frame count using two-dimensional OCT pullback not requiring off-line 3D reconstruction. For the analysis, consecutive frames were counted between the most distal and most proximal take-off of the SB frames.

Results

Similar to previous studies, quantitative coronary angiography findings were not associated with the functional significance of SBs after main vessel stenting. In contrast, SBOA assessed by 3D-OCT after provisional stenting strongly correlated with post-procedure SB FFR. The optimal cut-off value for the SBOA area to predict a SB FFR ≤0.80 was 0.76 mm2 (sensitivity 82%, specificity 89% and area under the curve of 0.92 (95% CI: 0.84–0.99). A simplified approach to SB ostium assessment using OCT frame count yielded a sensitivity of 82%, specificity 89% and area under the curve 0.92 (95% CI: 0.84 to 0.99) with a cut-off of 4.5 frames allowing detection of functionally significant SB stenoses during the procedure in real time. Figure 1 shows a receiver-operating characteristic curve for SB FFR ≤0.8 and a representative case with SB FFR = 0.66 after provisional stenting and SB ostium frame count equal 3 (Frame 1 to 3)

Conclusion(s)

Assessment of SB using either 3D OCT off-line reconstruction or a simplified approach based on OCT frame count can detect SB branches with FFR ≤0.80 with high sensitivity and specificity. The developed approaches may represent a useful tool to assess provisional stent outcomes.

Figure 1

Funding Acknowledgement

Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): Boston Scientific; St. Jude Medical