Safety and Feasibility Using a Fluid-Filled Wire to Avoid Hydrostatic Errors in Physiological Intracoronary Measurements

Background

Using a fluid-filled wire with a pressure sensor outside the patient compared to a conventional pressure wire may avoid the systematic error introduced by the hydrostatic pressure within the coronary circulation.

Aims

To assess the safety and effectiveness of the novel fluid-filled wire, Wirecath (Cavis Technologies, Uppsala, Sweden), as well as its ability to avoid the hydrostatic pressure error.

Methods and Results

The Wirecath pressure wire was used in 45 eligible patients who underwent invasive coronary angiography and had a clinical indication for invasive coronary pressure measurement at Sahlgrenska University Hospital, Gothenburg, Sweden. In 29 patients, a simultaneous measurement was performed with a conventional coronary pressure wire (PressureWire X, Abbott Medical, Plymouth, MN, USA), and in 19 patients, the vertical height difference between the tip of the guide catheter and the wire measure point was measured in a 90-degree lateral angiographic projection. No adverse events caused by the pressure wires were reported. The mean Pd/Pa and mean FFR using the fluid-filled wire and the sensor-tipped wire differed significantly; however, after correcting for the hydrostatic effect, the sensor-tipped wire pressure correlated well with the fluid-filled wire pressure (R = 0.74 vs. R = 0.89 at rest and R = 0.89 vs. R = 0.98 at hyperemia).

Conclusion

Hydrostatic errors in physiologic measurements can be avoided by using the fluid-filled Wirecath wire, which was safe to use in the present study. This trial is registered with NCT04776577 and NCT04802681.

OCT or Angiography Guidance for PCI in Complex Bifurcation Lesions

BACKGROUND

Imaging-guided percutaneous coronary intervention (PCI) is associated with better clinical outcomes than angiography-guided PCI. Whether routine optical coherence tomography (OCT) guidance in PCI of lesions involving coronary-artery branch points (bifurcations) improves clinical outcomes as compared with angiographic guidance is uncertain.

METHODS

We conducted a multicenter, randomized, open-label trial at 38 centers in Europe. Patients with a clinical indication for PCI and a complex bifurcation lesion identified by means of coronary angiography were randomly assigned in a 1:1 ratio to OCT-guided PCI or angiography-guided PCI. The primary end point was a composite of major adverse cardiac events (MACE), defined as death from a cardiac cause, target-lesion myocardial infarction, or ischemia-driven target-lesion revascularization at a median follow-up of 2 years.

RESULTS

We assigned 1201 patients to OCT-guided PCI (600 patients) or angiography-guided PCI (601 patients). A total of 111 patients (18.5%) in the OCT-guided PCI group and 116 (19.3%) in the angiography-guided PCI group had a bifurcation lesion involving the left main coronary artery. At 2 years, a primary end-point event had occurred in 59 patients (10.1%) in the OCT-guided PCI group and in 83 patients (14.1%) in the angiography-guided PCI group (hazard ratio, 0.70; 95% confidence interval, 0.50 to 0.98; P = 0.035). Procedure-related complications occurred in 41 patients (6.8%) in the OCT-guided PCI group and 34 patients (5.7%) in the angiography-guided PCI group.

CONCLUSIONS

Among patients with complex coronary-artery bifurcation lesions, OCT-guided PCI was associated with a lower incidence of MACE at 2 years than angiography-guided PCI. (Funded by Abbott Vascular and others; OCTOBER ClinicalTrials.gov number, NCT03171311.).

Impact of Computational Modeling on Transcatheter Left Atrial Appendage Closure Efficiency and Outcomes

BACKGROUND

When performing transcatheter left atrial appendage (LAA) closure, peridevice leaks and device-related thrombus (DRT) have been associated with worse clinical outcomes-hence, their risk should be mitigated.

OBJECTIVES

The authors sought to assess whether use of preprocedural computational modeling impacts procedural efficiency and outcomes of transcatheter LAA closure.

METHODS

The PREDICT-LAA trial (NCT04180605) is a prospective, multicenter, randomized trial in which 200 patients were 1:1 randomized to standard planning vs cardiac computed tomography (CT) simulation-based planning of LAA closure with Amplatzer Amulet. The artificial intelligence-enabled CT-based anatomical analyses and computer simulations were provided by FEops (Belgium).

RESULTS

All patients had a preprocedural cardiac CT, 197 patients underwent LAA closure, and 181 of these patients had a postprocedural CT scan (standard, n = 91; CT + simulation, n = 90). The composite primary endpoint, defined as contrast leakage distal of the Amulet lobe and/or presence of DRT, was observed in 41.8% in the standard group vs 28.9% in the CT + simulation group (relative risk [RR]: 0.69; 95% CI: 0.46-1.04; P = 0.08). Complete LAA closure with no residual leak and no disc retraction into the LAA was observed in 44.0% vs 61.1%, respectively (RR: 1.44; 95% CI: 1.05-1.98; P = 0.03). In addition, use of computer simulations resulted in improved procedural efficiency with use of fewer Amulet devices (103 vs 118; P < 0.001) and fewer device repositionings (104 vs 195; P < 0.001) in the CT + simulation group.

CONCLUSIONS

The PREDICT-LAA trial demonstrates the possible added value of artificial intelligence-enabled, CT-based computational modeling when planning for transcatheter LAA closure, leading to improved procedural efficiency and a trend toward better procedural outcomes.

Predicting risk of future acute coronary syndromes, 1-year survival and the need for coronary angiography in unstable angina: a nationwide machine learning study

Background

We developed machine learning models to predict the need for coronary angiography, recurrent acute coronary syndromes (ACS) and 1-year survival in patients with chest pain and normal high-sensitivity troponins. We also studied whether hs-troponin levels within the normal range convey predictive information on these outcomes.

Purpose

We studied whether machine learning could reliably predict survival, risk of future ACS and rule out unnecessary angiographies in patients with chest pain and normal hs-troponins. We aimed to deploy these models as open-sourced web applications, to provide clinicians with individualized predictions. We also studied whether normal hs-troponin levels may serve as predictors of these outcomes.

Methods

We used the SWEDEHEART registry to include patients admitted due to chest pain, with normal high-sensitivity troponin T or I (hs-TnI, hs-TnT), who underwent angiography and did not receive a final diagnosis of acute myocardial infarction. We studied angiographic findings on segmental level, developed machine learning models for future ACS and death (within 1-year, modelled separately) and unnecessary coronary angiography, which was defined as angiography that did not lead to any intervention. Models predicting future ACS and 1-year survival included 130 candidate predictors and models for unnecessary angiography included 110 predictors. We built approximately 50'000 models, using gradient boosting, extreme gradient boosting, random forest, artificial neural networks and logistic regression.

Results

We included 9'314 patients. The 1-year mortality rate was 0.9% (n=78), rate of future ACS was 2.7% (n=251), and rate of unnecessary angiography was 61.5% (n=5455). Up to 40% had normal angiography. There was a strong association between troponin levels (within normal range) and severity of coronary atherosclerosis; e.g 32.4% in patients with hs-TnI 26–35 ng/L had &gt;50% stenosis in segment 6, as compared with 12.6% in those with hs-TnI 0–5 ng/L. All segments displayed similar associations with troponin levels. Mortality increased at hs-TnI levels above 10 ng/L for men, but not women. Age and sex adjusted hazard ratios for hs-TnI 25–35 vs hs-TnI 0–5 was 5.73 (2.14–15.35) for 1-year mortality. The strongest predictors of 1-year mortality were C-reactive protein, body mass index, estimated glomerular filtration rate, age, time from symptom onset to CCU admission, systolic blood pressure and hs-TnI. Extreme gradient boosting was the best performing model for all prediction tasks; AUC ROC in the test data sets were 0.77 for 1-year mortality, 0.77 for future ACS and 0.78 for unnecessary angiography, with excellent calibration.

Conclusion

Machine learning models can reliably predict 1-year risk of death or ACS, as well as predict unnecessary angiographies. Troponin levels within normal range constitute a strong predictor of all these outcomes, questioning the definition of normal troponin.

Funding Acknowledgement

Type of funding sources: Public hospital(s). Main funding source(s): Sahlgrenska University hospital

Characteristics, survival and neurological outcome in out-of-hospital cardiac arrest: A nationwide study of 56,203 cases with emphasis on cardiovascular comorbidities

Background

We studied clinical characteristics, survival and neurological outcomes in patients with pre-existing cardiovascular (CV) conditions who experienced an out-of-hospital cardiac arrest (OHCA).

Methods

We studied all cases of OHCA in the Swedish Registry for Cardiopulmonary Resuscitation (2010–2020). Patients were grouped according to the following pre-existing CV conditions prior: hypertension (HT), heart failure (HF) with HT, HF with ischemic heart disease (IHD), HF without HT or IHD, IHD, myocardial infarction (MI) and diabetes mellitus (DM), with groups being mutually exclusive. We studied 30-day survival and neurological outcomes using logistic and Cox regression.

Results

A total of 56,203 patients were included. The lowest rates of shockable rhythm occurred in cases with HT (19%), HF and HT (18%) and DM (18%). Median time to OHCA from diagnosis of HT was 2.0 years in cases aged 0–40 years at diagnosis of HT, 4.4 years in those aged 41–60 at diagnosis, 5.0 years in those aged 61–70 years, 5.6 years in those aged 71–80 years and 6.0 years in those aged 81 years or older. The lowest survival was noted for patients with HF and HT. Age and sex adjusted OR for CPC score 1 did not differ in any group.

Conclusion

The combination of HT and HF has the lowest survival of all cardiovascular comorbidities. Early onset of hypertension is a predictor for early cardiac arrest.

Trends in Clinical Practice and Outcomes After Percutaneous Coronary Intervention of Unprotected Left Main Coronary Artery

Background

The use of percutaneous coronary intervention (PCI) to treat unprotected left main coronary artery disease has expanded rapidly in the past decade. We aimed to describe nationwide trends in clinical practice and outcomes after PCI for left main coronary artery disease.

Methods and Results

Patients (n=4085) enrolled in the SCAAR (Swedish Coronary Angiography and Angioplasty Registry) as undergoing PCI for left main coronary artery disease from 2005 to 2017 were included. A count regression model was used to analyze time‐related differences in procedural characteristics. The 3‐year major adverse cardiovascular and cerebrovascular event rate defined as death, myocardial infarction, stroke, and repeat revascularization was calculated with the Kaplan‐Meier estimator and Cox proportional hazard model. The number of annual PCI procedures grew from 121 in 2005 to 589 in 2017 (389%). The increase was greater for men (479%) and individuals with diabetes (500%). Periprocedural complications occurred in 7.9%, decreasing from 10% to 6% during the study period. A major adverse cardiovascular and cerebrovascular event occurred in 35.7% of patients, falling from 45.6% to 23.9% (hazard ratio, 0.56; 95% CI, 0.41–0.78; P=0.001). Radial artery access rose from 21.5% to 74.2% and intracoronary diagnostic procedures from 14.0% to 53.3%. Use of bare‐metal stents and first‐generation drug‐eluting stents fell from 19.0% and 71.9%, respectively, to 0, with use of new‐generation drug‐eluting stents increasing to 95.2%.

Conclusions

Recent changes in clinical practice relating to PCI for left main coronary artery disease are characterized by a 4‐fold rise in procedures conducted, increased use of evidence‐based adjunctive treatment strategies, intracoronary diagnostics, newer stents, and more favorable outcomes.

Left atrial appendage occlusion vs novel oral anticoagulation for stroke prevention in atrial fibrillation: rationale and design of the multicenter randomized occlusion-AF trial

BACKGROUND

The prevalence of atrial fibrillation (AF) is increasing globally, which is a major clinical and public health concern due to the 5-fold increased risk of stroke. Oral anticoagulation with novel oral anticoagulants (NOACs) is the current primary option for stroke prevention in patients with AF, although it increases the risk of major bleeding. Patients with prior ischemic cerebrovascular events are at particularly high risk of both recurrent ischemic events and major bleeding. Left atrial appendage occlusion (LAAO) provides an alternative option for stroke prevention in high-risk patients, however, with currently limited evidence. Thus, randomized trials comparing LAAO to NOACs are needed.

OBJECTIVE

The Occlusion-AF trial is designed to assess whether LAAO is non-inferior to NOAC therapy for reduction of the combined endpoint of stroke, systemic embolism, major bleeding (Bleeding Academic Research Consortium ≥ 3) and all-cause mortality in patients with AF and a recent ischemic stroke or transient ischemic attack (TIA).

METHODS AND ANALYSIS

Investigator-initiated multicenter, multinational, randomized open-label non-inferiority trial with blinded outcome evaluation (PROBE design). Patients with documented AF, and an ischemic stroke or TIA within 6 months will be eligible for enrollment. Major exclusion criteria are modified Rankin Scale > 3 at enrollment, glomerular filtration rate < 15 ml/min, and life-expectancy less than 2 years. A total of 750 patients will be randomized 1:1 to receive either a NOAC or LAAO using the Amplatzer Amulet (Abbott, MN, USA) or Watchman FLX (Boston Scientific, MN, USA) with subsequent life-long aspirin 75 mg daily. Follow-up will be based on in-office and telephone follow-up in combination with long-term follow-up (10 years) through national hospital discharge registries in the individual Nordic countries. The primary outcome will be a composite endpoint of stroke, systemic embolism, major bleeding (BARC ≥ 3) and all-cause mortality at 2-year follow-up.

CONCLUSIONS

The Occlusion-AF trial is designed to compare LAAO to NOAC therapy for secondary stroke prevention in AF patients with a high risk of recurrent thromboembolic events, i.e. with previous ischemic stroke or TIA, and otherwise eligible for anticoagulation. The results are expected to contribute significantly to the understanding of the effects of LAAO compared to the standard contemporary pharmacological treatment in these patients.

Long-term mortality in patients with ischaemic heart failure revascularized with coronary artery bypass grafting or percutaneous coronary intervention: insights from the Swedish Coronary Angiography and Angioplasty Registry (SCAAR)

Aims 

To compare coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) for treatment of patients with heart failure due to ischaemic heart disease.

Methods and results 

We analysed all-cause mortality following CABG or PCI in patients with heart failure with reduced ejection fraction and multivessel disease (coronary artery stenosis >50% in ≥2 vessels or left main) who underwent coronary angiography between 2000 and 2018 in Sweden. We used a propensity score-adjusted logistic and Cox proportional-hazards regressions and instrumental variable model to adjust for known and unknown confounders. Multilevel modelling was used to adjust for the clustering of observations in a hierarchical database. In total, 2509 patients (82.9% men) were included; 35.8% had diabetes and 34.7% had a previous myocardial infarction. The mean age was 68.1 ± 9.4 years (47.8% were >70 years old), and 64.9% had three-vessel or left main disease. Primary designated therapy was PCI in 56.2% and CABG in 43.8%. Median follow-up time was 3.9 years (range 1 day to 10 years). There were 1010 deaths. Risk of death was lower after CABG than after PCI [odds ratio (OR) 0.62; 95% confidence interval (CI) 0.41–0.96; P = 0.031]. The risk of death increased linearly with quintiles of hospitals in which PCI was the preferred method for revascularization (OR 1.27, 95% CI 1.17–1.38, P  _trend < 0.001).

Conclusion 

In patients with ischaemic heart failure, long-term survival was greater after CABG than after PCI.

Intracardiac echocardiography for guidance of transcatheter left atrial appendage occlusion: An expert consensus document

Transcatheter left atrial appendage occlusion (LAAO) is an increasingly used alternative to oral anticoagulation in selected patients with atrial fibrillation. Intraprocedural imaging is a crucial for a successful intervention, with transesophageal echocardiography (TEE) as the current gold standard. Since some important limitations may affect TEE use, intracardiac echocardiography (ICE) is increasingly used as an alternative to TEE for guiding LAAO. The lack of a standardized imaging protocol has slowed the adoption of ICE into clinical practice. On the basis of current research and expert consensus, this paper provides a protocol for ICE support of left atrial appendage occlusion.

Radial artery access is associated with lower mortality in patients undergoing primary PCI: a report from the SWEDEHEART registry

OBJECTIVES

The purpose of this observational study was to evaluate the effects of radial artery access versus femoral artery access on the risk of 30-day mortality, inhospital bleeding and cardiogenic shock in patients with ST-elevation myocardial infarction undergoing primary percutaneous coronary intervention.

METHODS

We used data from the SWEDEHEART registry and included all patients who were treated with primary percutaneous coronary intervention in Sweden between 2005 and 2016. We compared patients who had percutaneous coronary intervention by radial access versus femoral access with regard to the primary endpoint of all-cause death within 30 days, using a multilevel propensity score adjusted logistic regression which included hospital as a random effect.

RESULTS

During the study period, 44,804 patients underwent primary percutaneous coronary intervention of whom 24,299 (54.2%) had radial access and 20,505 (45.8%) femoral access. There were 2487 (5.5%) deaths within 30 days, of which 920 (3.8%) occurred in the radial access and 1567 (7.6%) in the femoral access group. After propensity score adjustment, radial access was associated with a lower risk of death (adjusted odds ratio (OR) 0.70, 95% confidence interval (CI) 0.55-0.88, P = 0.025). We found no interaction between access site and age, gender and cardiogenic shock regarding 30-day mortality. Radial access was also associated with a lower adjusted risk of bleeding (adjusted OR 0.45, 95% CI 0.25-0.79, P = 0.006) and cardiogenic shock (adjusted OR 0.41, 95% CI 0.24-0.73, P = 0.002).

CONCLUSIONS

In patients with ST-elevation myocardial infarction, primary percutaneous coronary intervention by radial access rather than femoral access was associated with an adjusted lower risk of death, bleeding and cardiogenic shock. Our findings are consistent with, and add external validity to, recent randomised trials.

Value of FEops HEARTguide patient-specific computational simulations in the planning of left atrial appendage closure with the Amplatzer Amulet closure device: rationale and design of the PREDICT-LAA study

BACKGROUND

Optimal preprocedural planning is essential to ensure successful device closure of the left atrial appendage (LAA).

DESIGN

The PREDICT-LAA study is a prospective, international, multicentre, randomised controlled trial (ClinicalTrials.gov NCT04180605). Two hundred patients eligible for LAA closure with an Amplatzer Amulet device (Abbott, USA) will be enrolled in the study. Patients will be allocated to a computational simulation arm (experimental) or standard treatment arm (control) using a 1:1 randomisation. For patients randomised to the computational simulation arm, preprocedural planning will be based on the analysis of cardiac computed tomography (CCT)-based patient-specific computational simulations (FEops HEARTguide, Ghent, Belgium) in order to predict optimal device size and position. For patients in the control arm, preprocedural planning will be based on local practice including CCT analysis. The LAA closure procedure and postprocedural antithrombotic therapy will follow local practice in both arms. The primary endpoint of the study is incomplete LAA closure and device-related thrombus as assessed at 3 months postprocedural CCT. Secondary endpoints encompass procedural efficiency (number of devices used, number of repositioning, procedural time, radiation exposure, contrast dye), procedure-related complications within 7 days postprocedure and a composite of all-cause death and thromboembolic events at 12 months.

CONCLUSION

The objective of the PREDICT-LAA study is to test the hypothesis that a preprocedural planning for LAA closure with the Amplatzer Amulet device based on patient-specific computational simulations can result in a more efficient procedure, optimised procedural outcomes and better clinical outcomes as compared with a standard preprocedural planning.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Registry (NCT04180605).

Comparative Effectiveness of CABG versus PCI in Patients with Ischemic Heart Disease: insights from SWEDEHEART Registry

Background

Several studies have compared CABG to PCI as revascularization treatment in patients with ischemic heart disease (IHD). However, it remains unclear which revascularization strategy carries survival benefits in the long-term.

Methods

We used data from the SWEDEHEART (Swedish Web-System for Enhancement and Development of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies) registry for all hospital admissions at 13 cardiac care centers within Västra Götaland County in Sweden (∼20% of all SWEDEHEART data). The database contains &gt;1000 clinical variables documenting the entire process of acute coronary hospital care. All patients hospitalized for stable angina or NSTE-ACS during the period 2000–2018 were included in the analysis. We used a propensity score-adjusted Cox proportional-hazards regression with hospitals as random-effect variables. We adjusted for patients' demographics, socio-economic status, traditional risk factors, comorbidities, the severity of coronary artery disease, left ventricular function, calendar year and medication at discharge. For sensitivity analysis, we used the instrumental variable estimator for the Cox proportional-hazards model (with treating hospital as a treatment-preference instrument) to simultaneously deal with the problems of unmeasured confounding and censoring of the outcome. The primary outcome was all-cause mortality.

Results

In total, 11,896 patients were included in the study. Of these, 3,129 (26.3%) were women. 20.4% had diabetes and 10.4% had a previous myocardial infarction. The mean age was 66.7±10.7, and 42.9% were &gt;70 years old. 61.5% had three-vessel and/or left main disease. Median follow-up time was 5.7 years (range 1 day-18.2 years). Revascularization therapy after coronary angiography was PCI in 9449 (79.4%) and CABG in 2,447 (20.6%) patients. CABG patients were more likely to have diabetes, left main/multivessel disease and heart failure. The number of revascularized patients with PCI increased by 6.4% per calendar year (P&lt;0.001). There were 2,481 (20.9%) deaths. CABG was associated with a lower risk of death compared to PCI (HR 0.81; 95% CI 0.69–0.95; P=0.011. We found no evidence for treatment heterogeneity between the revascularization strategy and age, gender, diabetes, heart failure and indication for revascularization (all P-interaction &gt;0.05). Results from the sensitivity analysis support the conclusions from the primary model.

Conclusions

In hospitalized patients due to IHD, revascularization with CABG was associated with superior long-term survival compared to PCI.

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): Heart and Lung Foundation, ALF Västra Götaland, Swedish Scientific Council

Association of Pretreatment With P2Y12 Receptor Antagonists Preceding Percutaneous Coronary Intervention in Non-ST-Segment Elevation Acute Coronary Syndromes With Outcomes

IMPORTANCE

Pretreatment of patients with non-ST-segment elevation acute coronary syndrome (NSTE-ACS) with P2Y12 receptor antagonists is a common practice despite the lack of definite evidence for its benefit.

OBJECTIVE

To investigate the association of P2Y12 receptor antagonist pretreatment vs no pretreatment with mortality, stent thrombosis, and in-hospital bleeding in patients with NSTE-ACS undergoing percutaneous coronary intervention (PCI).

DESIGN, SETTING, AND PARTICIPANTS

This cohort study used prospective data from the Swedish Coronary Angiography and Angioplasty Registry of 64 857 patients who underwent procedures between 2010 and 2018. All patients who underwent PCI owing to NSTE-ACS in Sweden were stratified by whether they were pretreated with P2Y12 receptor antagonists. Associations of pretreatment with P2Y12 receptor antagonists with the risks of adverse outcomes were investigated using instrumental variable analysis and propensity score matching. Data were analyzed from March to June 2019.

EXPOSURES

Pretreatment with P2Y12 receptor antagonists.

MAIN OUTCOMES AND MEASURES

The primary end point was all-cause mortality within 30 days. Secondary end points were 1-year mortality, stent thrombosis within 30 days, and in-hospital bleeding.

RESULTS

In total, 64 857 patients (mean [SD] age, 64.7 [10.9] years; 46 809 [72.2%] men) were included. A total of 59 894 patients (92.4%) were pretreated with a P2Y12 receptor antagonist, including 27 867 (43.7%) pretreated with clopidogrel, 34 785 (54.5%) pretreated with ticagrelor, and 1148 (1.8%) pretreated with prasugrel. At 30 days, there were 971 deaths (1.5%) and 101 definite stent thromboses (0.2%) in the full cohort. Pretreatment was not associated with better survival at 30 days (odds ratio [OR], 1.17; 95% CI, 0.66-2.11; P = .58), survival at 1 year (OR, 1.34; 95% CI, 0.77-2.34; P = .30), or decreased stent thrombosis (OR, 0.81; 95% CI, 0.42-1.55; P = .52). However, pretreatment was associated with increased risk of in-hospital bleeding (OR, 1.49; 95% CI, 1.06-2.12; P = .02).

CONCLUSIONS AND RELEVANCE

This cohort study found that pretreatment of patients with NSTE-ACS with P2Y12 receptor antagonists was not associated with improved clinical outcomes but was associated with increased risk of bleeding. These findings support the argument that pretreatment with P2Y12 receptor antagonists should not be routinely used in patients with NSTE-ACS.

Ticagrelor is Not Superior to Clopidogrel in Patients With Acute Coronary Syndromes Undergoing PCI: A Report from Swedish Coronary Angiography and Angioplasty Registry

Background

Ticagrelor reduces ischaemic end points in acute coronary syndromes. However, outcomes of ticagrelor versus clopidogrel in real‐world patients with acute coronary syndromes treated with percutaneous coronary intervention (PCI) remain unclear. We sought to examine whether treatment with ticagrelor is superior to clopidogrel in unselected patients with acute coronary syndromes treated with PCI.

Methods and Results

We used data from SCAAR (Swedish Coronary Angiography and Angioplasty Registry) for PCI performed in Västra Götaland County, Sweden. The database contains information about all PCI performed at 5 hospitals (∼20% of all data in SCAAR). All procedures between January 2005 and January 2015 for unstable angina/non‒ST‐segment‒elevation myocardial infarction and ST‐segment‒elevation myocardial infarction were included. We used instrumental variable 2‐stage least squares regression to adjust for confounders. The primary combined end point was mortality or stent thrombosis at 30 days, secondary end points were mortality at 30 days and 1‐year, stent thrombosis at 30 days, in‐hospital bleeding, in‐hospital neurologic complications and long‐term mortality. A total of 15 097 patients were included in the study of which 2929 (19.4%) were treated with ticagrelor. Treatment with ticagrelor was not associated with a lower risk for the primary end point (adjusted odds ratio [aOR], 1.20; 95% CI, 0.87–1.61; P=0.250). Estimated risk of death at 30 days (aOR, 1.18; 95% CI, 0.88–1.64; P=0.287) and at 1‐year (aOR, 1.28; 95% CI, 0.86–1.64; P=0.556) was not different between the groups. The risk of in‐hospital bleeding was higher with ticagrelor (aOR, 2.88; 95% CI, 1.53–5.44; P=0.001).

Conclusions

In this observational study, treatment with ticagrelor was not superior to clopidogrel in patients with acute coronary syndromes treated with PCI.

Prognostic impact of percutaneous coronary intervention in octogenarians with non-ST elevation myocardial infarction: A report from SWEDEHEART

AIMS

Percutaneous coronary intervention (PCI) improves outcomes in non-ST elevation acute coronary syndromes (NSTE-ACSs). Octogenarians, however, were underrepresented in the pivotal trials. This study aimed to assess the effect of PCI in patients ≥80 years old.

METHODS AND RESULTS

We used data from the SWEDEHEART registry for all hospital admissions at eight cardiac care centres within Västra Götaland County. Consecutive patients ≥80 years old admitted for NSTE-ACS between January 2000 and December 2011 were included. We performed instrumental variable analysis with propensity score. The primary endpoint was all-cause mortality at 30 days and one year after index hospitalization. During the study period 5200 patients fulfilled the inclusion criteria. In total, 586 (11.2%) patients underwent PCI, the remaining 4613 patients were treated conservatively. Total mortality at 30 days was 19.4% (1007 events) and 39.4% (1876 events) at one year. Thirty-day mortality was 20.7% in conservatively treated patients and 8.5% in the PCI group (adjusted odds ratio 0.34; 95% confidence interval 0.12-0.97, p = 0.044). One-year mortality was 42.1% in the conservatively treated group and 16.3% in the PCI group (adjusted odds ratio 0.97; 95% confidence interval 0.36-2.51, p = 0.847).

CONCLUSIONS

PCI in octogenarians with NSTE-ACS was associated with a lower risk of mortality at 30 days. However, this survival benefit was not sustained during the entire study-period of one-year.

PROspective evaluation of coronary FLOW reserve and molecular biomarkers in patients with established coronary artery disease the PROFLOW-trial: cross-sectional evaluation of coronary flow reserve

Background

Survivors of myocardial infarction (MI) are at high risk of new major adverse cardiovascular events (MACE). Coronary flow reserve (CFR) is a strong and independent predictor of MACE. Understanding the prevalence of impaired CFR in this patient group and identifying risk markers for impaired CFR are important steps in the development of personalized and targeted treatment for high-risk individuals with prior MI.

Methods

PROFLOW is a prospective, exploratory, cross-sectional open study. We used information from the SCAAR (Swedish Coronary Angiography and Angioplasty Registry) to identify high-risk patients with a history of type-1 MI. We measured CFR non-invasively in a left anterior descending artery (LAD) using transthoracic Doppler echocardiography. Coronary flow velocity was measured at rest and at maximal flow after induction of hyperemia by intravenous infusion of adenosine (140 μg/kg/min). Independent predictors of CFR were assessed with multiple linear regression.

Results

We included 619 patients. The median age was 69 (IQR 65–73), and 114 (18.4%) were women. Almost one-half of the patients, 285 (46.0%) had the multi-vessel disease, and 147 (23.7%) were incompletely revascularized. The majority were on optimal standard treatment eg ASA (93.1%), statins (90.0%), ACEI/ARB (82.6%) and beta-blockers (80.8%). The majority, 547 (88.4%) had no angina pectoris, and 572 (92.2%) were in NYHA class I. Evaluation of CFR was possible in 611 (98.7%) patients. Mean CFR was 2.74 (±0.79 (mean ± SD)). A substantial number of patients (39.7%) had CFR ≤2.5. In a multiple linear regression model age, dyslipidemia, smoking, hypertension, body mass index, incomplete revascularization, and treatment with angiotensin receptor blockers were independent predictors of CFR.

Conclusion

In this high-risk group of patients with prior MI, the prevalence of impaired CFR was high. Further risk stratification with CFR in addition to traditional cardiovascular risk factors may improve predictive accuracy for future MACE in this patient population.

Left atrial appendage occlusion versus standard medical care in patients with atrial fibrillation and intracerebral haemorrhage: a propensity score-matched follow-up study

AIMS

The aim of this study was to investigate the prognosis in patients with atrial fibrillation (AF) and intracerebral haemorrhage (ICH) having a left atrial appendage occlusion (LAAO) versus patients receiving standard medical therapy.

METHODS AND RESULTS

A total of 151 patients from the Nordic countries with AF and previous ICH who underwent LAAO using the AMPLATZER Cardiac Plug or the AMPLATZER AMULET were compared to a propensity score-matched group of 151 patients receiving standard medical therapy. The two groups were matched so that their risks for stroke and bleeding were similar (CHA2DS2-VASc and HAS-BLED scores). The standard care patients were identified from the Danish Stroke Registry among 787 patients with AF and ICH. The primary endpoint was a composite of all-cause mortality, ischaemic stroke and major bleeding. Patients with AF and a prior ICH treated with LAAO had a lower risk of the composite outcome as compared to patients treated with standard medical care (events/1,000 years [95% confidence interval]: 53.3 [44.3-64.1] vs. 366.7 [298.2-450.9]; hazard ratio 0.16 [0.07-0.37]).

CONCLUSIONS

LAAO is suggested to be of major clinical benefit in AF patients having sustained an ICH. These results have to be confirmed in a randomised clinical trial.

Impact of Thrombus Aspiration on Mortality, Stent Thrombosis, and Stroke in Patients With ST-Segment-Elevation Myocardial Infarction: A Report From the Swedish Coronary Angiography and Angioplasty Registry

Background

Thrombus aspiration is still being used in a substantial number of patients despite 2 large randomized clinical trials showing no favorable effect of routine thrombus aspiration during primary percutaneous coronary intervention in patients with ST‐segment–elevation myocardial infarction. The aim of this observational study was to evaluate the impact of thrombus aspiration on mortality, stent thrombosis, and stroke using all available data from the Swedish Coronary Angiography and Angioplasty Registry (SCAAR).

Methods and Results

We identified 42 829 consecutive patients registered in SCAAR between January 2005 and September 2014 who underwent percutaneous coronary intervention for ST‐segment–elevation myocardial infarction. Thrombus aspiration was used in 25% of the procedures. We used instrumental variable analysis with administrative healthcare region as the treatment‐preference instrumental variable to evaluate the effect of thrombus aspiration on mortality, stent thrombosis, and stroke. Thrombus aspiration was not associated with mortality at 30 days (risk reduction: −1.2; 95% confidence interval [CI], −5.4 to 3.0; P=0.57) and 1 year (risk reduction: −2.4; 95% CI, −7.6 to 3.0; P=0.37). Thrombus aspiration was associated with a lower risk of stent thrombosis both at 30 days (risk reduction: −2.7; 95% CI, −4.1 to −1.4; P<0.001) and 1 year (risk reduction: −3.5; 95% CI, −5.3 to −1.7; P<0.001). In‐hospital stroke and neurologic complications did not differ between groups (risk reduction: 0.1; 95% CI, −0.8 to 1.1; P=0.76).

Conclusions

Mortality was not different between the groups. Thrombus aspiration was associated with decreased risk of stent thrombosis. Our study provides important evidence for the external validity of previous randomized studies regarding mortality.

Prognostic Impact of Chronic Total Occlusions: A Report From SCAAR (Swedish Coronary Angiography and Angioplasty Registry)

OBJECTIVES

The aim of this study was to determine the prognostic impact of chronic total occlusion (CTO) on long-term mortality in a large prospective cohort.

BACKGROUND

CTO is present in many patients with coronary artery disease and is difficult to treat with percutaneous coronary intervention.

METHODS

The study population consisted of all consecutive patients who underwent coronary angiography in Sweden between January 1, 2005 and January 1, 2012, who were registered in SCAAR (Swedish Coronary Angiography and Angioplasty Registry). The patient population was heterogeneous with regard to indication for angiography (stable angina, ST-segment elevation myocardial infarction [STEMI], unstable angina or non-STEMI, and other) and treatment options. The long-term mortality rates of patients with and without CTO were compared by using shared frailty Cox proportional hazards regression adjusted for confounders. Tests were conducted for interactions between CTO and several pre-specified characteristics: indication for angiography and percutaneous coronary intervention (stable angina, STEMI, unstable angina or non-STEMI, and other), severity of coronary artery disease (1-, 2-, and 3-vessel and/or left main coronary artery disease), age, sex, and diabetes.

RESULTS

During the study period, 14,441 patients with CTO and 75,431 patients without CTO were registered in SCAAR. CTO was associated with higher mortality (hazard ratio: 1.29; 95% confidence interval: 1.22 to 1.37; p < 0.001). In subgroup analyses, the risk attributable to CTO was lowest in patients with stable angina and highest in those with STEMI. In addition, CTO was associated with highest risk in patients under 60 years of age and with lowest risk in octogenarians. There was no interaction between CTO and either diabetes or sex, suggesting an equally adverse effect in both groups.

CONCLUSIONS

In this large prospective observational study of patients with coronary artery disease, CTO was associated with increased mortality. This association was most prominent in younger patients and in those with acute coronary syndromes.

Hypertension is associated with increased mortality in patients with ischaemic heart disease after revascularization with percutaneous coronary intervention - a report from SCAAR

BACKGROUND

The prognostic role of hypertension on long-term survival after percutaneous coronary intervention (PCI) is limited and inconsistent. We hypothesize that hypertension increases long-term mortality after PCI.

METHODS

We analyzed data from SCAAR (Swedish Coronary Angiography and Angioplasty Registry) for all consecutive patients admitted coronary care units in Sweden between January 1995 and May 2013 and who underwent PCI due to ST-elevation myocardial infarction (STEMI), non-ST-elevation myocardial infarction (NSTEMI)/unstable angina (UA) or stable angina pectoris. We used Cox proportional-hazards regression for statistical modelling on complete-case data as well as on imputed data sets. We used interaction test to evaluate possible effect-modulation of hypertension on risk estimates in several pre-specified subgroups: age categories, gender, diabetes, smoking and indication for PCI (STEMI, NSTEMI/UA and stable angina).

RESULTS

During the study period, 175,892 consecutive patients underwent coronary angiography due to STEMI, NSTEMI/UA or stable angina. 78,100 (44%) of these had hypertension. Median follow-up was 5.5 years. After adjustment for differences in patient's characteristics, hypertension was associated with increased risk for mortality (HR 1.12, 95% CI 1.09-1.15, p < .001). In subgroup analysis, risk was highest in patients less than 65 years, in smokers and in patients with STEMI. The risk was lowest in patients with stable angina (p < .001 for interaction test).

CONCLUSION

Hypertension is associated with higher mortality in patients with STEMI, NSTEMI/UA or stable angina who are treated with PCI.

Trends in Gender Differences in Cardiac Care and Outcome After Acute Myocardial Infarction in Western Sweden: A Report From the Swedish Web System for Enhancement of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies (SWEDEHEART)

BACKGROUND

Cardiovascular disease is the most common cause of death for both genders. Debates are ongoing as to whether gender-specific differences in clinical course, diagnosis, and management of acute myocardial infarction (MI) exist.

METHODS AND RESULTS

We compared all men and women who were treated for acute MI at cardiac care units in Västra Götaland, Sweden, between January 1995 and October 2014 by obtaining data from the prospective SWEDEHEART (Swedish Web-System for Enhancement of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies) registry. We performed unadjusted and adjusted Cox proportional hazards and logistic regression analyses on complete case data and on imputed data sets. Overall, 48 118 patients (35.4% women) were diagnosed with acute MI. Women as a group had better age-adjusted prognosis than men, but this survival benefit was absent for younger women (aged <60 years) and for women with ST-segment elevation MI. Compared with men, younger women and women with ST-segment elevation MI were more likely to develop prehospital cardiogenic shock (adjusted odds ratio 1.67, 95% CI 1.30 to 2.16, P<0.001 and adjusted odds ratio 1.31, 95% CI 1.16 to 1.48, P<0.001) and were less likely to be prescribed evidence-based treatment at discharge (P<0.001 for β-blockers, angiotensin-converting enzyme inhibitors or angiotensin receptor blockers, statins, and P2Y12 antagonists). Differences in treatment between the genders did not decrease over the study period (P>0.1 for all treatments).

CONCLUSIONS

Women on average have better adjusted prognosis than men after acute MI; however, younger women and women with ST-segment elevation MI have disproportionately poor prognosis and are less likely to be prescribed evidence-based treatment.

Outcomes 1 year after thrombus aspiration for myocardial infarction

BACKGROUND

Routine intracoronary thrombus aspiration before primary percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction (STEMI) has not been proved to reduce short-term mortality. We evaluated clinical outcomes at 1 year after thrombus aspiration.

METHODS

We randomly assigned 7244 patients with STEMI to undergo manual thrombus aspiration followed by PCI or to undergo PCI alone, in a registry-based, randomized clinical trial. The primary end point of all-cause mortality at 30 days has been reported previously. Death from any cause at 1 year was a prespecified secondary end point of the trial.

RESULTS

No patients were lost to follow-up. Death from any cause occurred in 5.3% of the patients (191 of 3621 patients) in the thrombus-aspiration group, as compared with 5.6% (202 of 3623) in the PCI-only group (hazard ratio, 0.94; 95% confidence interval [CI], 0.78 to 1.15; P=0.57). Rehospitalization for myocardial infarction at 1 year occurred in 2.7% and 2.7% of the patients, respectively (hazard ratio, 0.97; 95% CI, 0.73 to 1.28; P=0.81), and stent thrombosis in 0.7% and 0.9%, respectively (hazard ratio, 0.84; 95% CI, 0.50 to 1.40; P=0.51). The composite of death from any cause, rehospitalization for myocardial infarction, or stent thrombosis occurred in 8.0% and 8.5% of the patients, respectively (hazard ratio, 0.94; 95% CI, 0.80 to 1.11; P=0.48). The results were consistent across all the major subgroups, including grade of thrombus burden and coronary flow before PCI.

CONCLUSIONS

Routine thrombus aspiration before PCI in patients with STEMI did not reduce the rate of death from any cause or the composite of death from any cause, rehospitalization for myocardial infarction, or stent thrombosis at 1 year. (Funded by the Swedish Research Council and others; TASTE ClinicalTrials.gov number, NCT01093404.).

Chronic total occlusions in Sweden--a report from the Swedish Coronary Angiography and Angioplasty Registry (SCAAR)

INTRODUCTION

Evidence for the current guidelines for the treatment of patients with chronic total occlusions (CTO) in coronary arteries is limited. In this study we identified all CTO patients registered in the Swedish Coronary Angiography and Angioplasty Registry (SCAAR) and studied the prevalence, patient characteristics and treatment decisions for CTO in Sweden.

METHODS AND RESULTS

Between January 2005 and January 2012, 276,931 procedures (coronary angiography or percutaneous coronary intervention) were performed in 215,836 patients registered in SCAAR. We identified all patients who had 100% luminal diameter stenosis known or assumed to be ≥ 3 months old. After exclusion of patients with previous coronary artery bypass graft (CABG) surgery or coronary occlusions due to acute coronary syndrome, we identified 16,818 CTO patients. A CTO was present in 10.9% of all coronary angiographies and in 16.0% of patients with coronary artery disease. The majority of CTO patients were treated conservatively and PCI of CTO accounted for only 5.8% of all PCI procedures. CTO patients with diabetes and multivessel disease were more likely to be referred to CABG.

CONCLUSION

CTO is a common finding in Swedish patients undergoing coronary angiography but the number of CTO procedures in Sweden is low. Patients with CTO are a high-risk subgroup of patients with coronary artery disease. SCAAR has the largest register of CTO patients and therefore may be valuable for studies of clinical importance of CTO and optimal treatment for CTO patients.

Does the timing of treatment with intra-aortic balloon counterpulsation in cardiogenic shock due to ST-elevation myocardial infarction affect survival?

BACKGROUND

Intra-aortic balloon pump (IABP) counterpulsation and primary percutaneous coronary intervention (PCI) are standard treatment modalities in cardiogenic shock (CS) complicating acute myocardial infarction. The aim of this study was to investigate the impact of the timing of IABP treatment start in relation to PCI procedure.

METHODS

Data were obtained from the SCAAR registry (Swedish Coronary Angiography and Angioplasty Registry) about 139 consecutive patients with CS due to ST-elevation myocardial infarction (STEMI) who received IABP treatment. The patients were hospitalized at Sahlgrenska University Hospital, Gothenburg, during 2004-2008. The cohort was divided into the two groups: group (A) in whom IABP treatment started before start of PCI (n = 72) and group (B) in whom IABP treatment started after PCI treatment (n = 67). The primary endpoint was 30-day mortality. Propensity score (PS) adjusted Cox proportional hazards regression was used to analyze predictors of 30-day mortality.

RESULTS

Mean age was 66.5 ± 12 and 28% were women. All patients have received IABP treatment 30 min before or 30 min after primary PCI. 63% had diabetes and 28% had hypertension. 16% were active tobacco smokers. The mortality rate at 30 days was 38%. IABP treatment commenced before or after PCI was not an independent predictor of mortality (P = 0.72).

CONCLUSION

In this non-randomized trial the treatment with insertion of IABP before primary PCI in patients with CS due to STEMI is not associated with a more favorable outcome as compared with IABP started after primary PCI.

Evaluation of dosage, safety and effects of methylphenidate on post-traumatic brain injury symptoms with a focus on mental fatigue and pain

OBJECTIVE

The neurobehavioural symptoms and pain following traumatic brain injury (TBI) can be long-lasting. The condition impairs the persons' ability to function in their work, studies and gatherings with family and friends. The aim of this study was to investigate dosage, safety and effects of methylphenidate on mental fatigue and pain.

METHODS

Twenty-nine physically-well rehabilitated TBI victims, 28 with a mild TBI and one with TBI and also with pain in the neck, shoulders and head were included in the study. Methylphenidate was tested in each patient using three treatment strategies: no medication, low dose (5 mg × 3) and normal dose (20 mg × 3) for 4 weeks using a randomized cross-over design.

RESULTS

Twenty-four patients completed the three treatment periods. Five participants discontinued, four females due to adverse reactions and one male due to attenuated motivation. Only minor adverse events were reported. Methylphenidate significantly decreased mental fatigue, as evaluated by the Mental Fatigue Scale (p < 0.001), and the effects on mental fatigue were dose-dependent. No effect on pain was detected.

CONCLUSIONS

Methylphenidate decreased mental fatigue for subjects suffering a traumatic brain injury, the treatment is considered to be safe and is recommended, starting with a low dose.

Vectorcardiography analysis of the repolarization response to pharmacologically induced autonomic nervous system modulation in healthy subjects

Autonomic nervous system activity is essential for regulation of ventricular repolarization (VR) and plays an important role in several arrhythmogenic conditions. This study in 31 healthy adult subjects (16 men, 15 women) evaluated the VR response to pharmacologically modulated autonomic nervous system activity applying vectorcardiography (VCG) analysis. During continuous VCG recording, 0.01-0.1 μg·kg(-1)·min(-1) isoprenaline (Iso) was infused at an increasing flow rate until three targeted heart rates (HR) were reached. After Iso washout, one intravenous bolus of 0.04 mg/kg atropine was given followed by an intravenous bolus of 0.2 mg/kg propranolol. A 5-min steady-state VCG recording was analyzed for each of the seven phases (including baseline 1 and 2). Furthermore, during the first 4 min following atropine, six periods of 10-s VCG were selected for subanalysis to evaluate the time course of change. The analysis included QRS, QT, and T-peak to T-end intervals, measures of the QRS and T vectors and their relation, as well as T-loop morphology parameters. By increasing HR, Iso infusion decreased HR dependent parameters reflecting total heterogeneity of VR (T area) and action potential morphology (ventricular gradient). In contrast, Iso prolonged QT HR corrected according to Bazett and increased the T-peak to T-end-to-QT ratio to levels observed in arrhythmogenic conditions. HR acceleration after atropine was accompanied by a transient paradoxical QT prolongation and delayed HR adaptation of T area and ventricular gradient. In addition to the expected HR adaptation, the VR response to β-adrenoceptor stimulation with Iso and to muscarinic receptor blockade with atropine thus included alterations previously observed in congenital and acquired long QT syndromes, demonstrating substantial overlap between physiological and pathophysiological electrophysiology.

Failure to demonstrate myocardial protective effects of the ultra short-acting calcium antagonist clevidipine in a closed-chest reperfusion porcine model

Restoration of myocardial perfusion is essential in acute myocardial infarction for the salvaging of myocardial tissue. However, reperfusion per se can provoke myocardial necrosis within the jeopardized tissue. Yet, no intervention has been successfully applied to the clinical situation in this matter. Clevidipine, an ultra-short acting calcium antagonist, has, in open-chest animal models, shown to reduce the extent of reperfusion injury. In the present study we intended to reproduce those findings in a closed-chest porcine model with a clinically applicable set up. Pigs were subjected to balloon occlusion of the left anterior descending coronary artery (LAD) for 45 minutes. During 25 minutes, starting 1 minute prior to reperfusion, clevidipine, Intralipid, or saline was infused antegradely into the endangered myocardium. As no significant effects on infarct size were achieved, the model was modified. In a second phase, different anesthesias were evaluated addressing the same issue. Nonetheless no significant effects on infarct size were observed. Different techniques of occluding LAD, in an open-chest model, were investigated in a third phase, and revealed no significant differences between the techniques. However, when comparing all the closed- versus open-chest models, significant reduction in infarct size by the use of clevidipine was only obtained in the open-chest models. We could not demonstrate any significant myocardial protective effect with clevidipine in our porcine, closed-chest, acute infarct, and reperfusion model. However, in a modified open-chest model we obtained significant reduction in infarct size. Further studies are required to explain the discrepancies.

Endocardial electromechanical mapping in a porcine acute infarct and reperfusion model evaluating the extent of myocardial ischemia

OBJECTIVE

Catheter-based, left ventricular, electromechanical mapping (EMM) has evolved as a diagnostic tool to characterize ischemic and injured myocardium. In the acute setting, diagnostic criteria for ischemic or infarcted myocardium are not well defined. In the present study, the capacity of separating myocardium with evolving necrosis from viable myocardium was investigated.

METHODS AND RESULTS

Pigs were subjected to balloon occlusion of the left anterior descending coronary artery for 45 minutes. Using the NOGATM cardiac mapping system, EMM was performed at the baseline and after two hours of reperfusion. EMMs were evaluated regarding unipolar voltage (UPV), bipolar voltage (BPV) and local linear shortening (LLS). The pigs were sacrificed four hours after reperfusion and morphological estimation of infarct size and localization was performed. Baseline UPV activity was significantly lower in the anterior, lateral and posterior basal segments as compared to the septal and posterior midventricular segments. After reperfusion, UPV, but not BPV, was significantly decreased in the apical, midventricular septal and basal segments. LLS demonstrated significant impairment of mobility in the septal midventricular segment. The thresholds for separating electromechanical activity at baseline from after infarction differed between the myocardial regions. The ability of EMM to correctly detect infarcted myocardium showed a sensitivity and specificity in the order of 50 85%, as compared to the morphological standard.

CONCLUSION

In a porcine acute infarct and reperfusion model, electromechanical activity thresholds, for infarct detection, could be established, but there was significant intersegmental threshold variability at baseline and after infarction. Accordingly, applying general thresholds demonstrated a poor correlation between infarct extension evaluated by EMM and morphology.