Cardiac Myosin-Binding Protein C to Diagnose Acute Myocardial Infarction in the Pre-Hospital Setting

Background Early triage is essential to improve outcomes in patients with suspected acute myocardial infarction (AMI). This study investigated whether cMyC (cardiac myosin-binding protein), a novel biomarker of myocardial necrosis, can aid early diagnosis of AMI and risk stratification. Methods and Results cMyC and high-sensitivity cardiac troponin T were retrospectively quantified in blood samples obtained by ambulance-based paramedics in a prospective, diagnostic cohort study. Patients with ongoing or prolonged periods of chest discomfort, acute dyspnoea in the absence of known pulmonary disease, or clinical suspicion of AMI were recruited. Discrimination power was evaluated by calculating the area under the receiver operating characteristics curve; diagnostic performance was assessed at predefined thresholds. Diagnostic nomograms were derived and validated using bootstrap resampling in logistic regression models. Seven hundred seventy-six patients with median age 68 [58;78] were recruited. AMI was the final adjudicated diagnosis in 22%. Median symptom to sampling time was 70 minutes. cMyC concentration in patients with AMI was significantly higher than with other diagnoses: 98 [43;855] versus 17 [9;42] ng/L. Discrimination power for AMI was better with cMyC than with high-sensitivity cardiac troponin T (area under the curve, 0.839 versus 0.813; P=0.005). At a previously published rule-out threshold (10 ng/L), cMyC reaches 100% sensitivity and negative predictive value in patients after 2 hours of symptoms. In logistic regression analysis, cMyC is superior to high-sensitivity cardiac troponin T and was used to derive diagnostic and prognostic nomograms to evaluate risk of AMI and death. Conclusions In patients undergoing blood draws very early after symptom onset, cMyC demonstrates improved diagnostic discrimination of AMI and could significantly improve the early triage of patients with suspected AMI.

Rationale and design of DanGer shock: Danish-German cardiogenic shock trial

OBJECTIVE

The DanGer Shock trial test the hypothesis that left ventricular (LV) mechanical circulatory support with Impella CP transvalvular microaxial flow pump improves survival in patients with ST segment elevation acute myocardial infarction complicated by cardiogenic shock (AMICS) compared to conventional guideline-driven treatment. This paper describes the rationale and design of the randomized trial, in addition to the baseline characteristics of the population screened and enrolled so far.

METHODS

The DanGer Shock study is a prospective, multicenter, open-label trial in patients with AMICS randomized 1:1 to Impella CP or current guideline-driven therapy with planned enrollment of 360 patients. Patients comatose after out of hospital cardiac arrest are excluded. Eligible patients are randomized immediately following shock diagnosis. Among patients randomized to receive Impella CP, the device is placed prior to angioplasty. The primary endpoint is all-cause mortality at 180 days. Baseline characteristics of patients screened and randomized in the DanGer Shock as of June 2018 are compared with 2 contemporary AMICS studies.

RESULTS

As of end of June 2018, 314 patients were screened and 100 patients were randomized. Patients had median arterial lactate of 5.5 mmol/L (interquartile range 3.7-8.8 mmol/L), median systolic blood pressure of 76 mmHg (interquartile range 70-88 mmHg), and median LV ejection fraction of 20% (interquartile range 10%-30%).

CONCLUSION

The DanGer Shock trial will be the first adequately powered randomized trial to address whether mechanical circulatory LV support with Impella CP can improve survival in AMICS. Baseline characteristics of the first 100 randomized patients indicate a population in profound cardiogenic shock.

Interaction of ischaemic postconditioning and thrombectomy in patients with ST-elevation myocardial infarction

OBJECTIVE

The Third Danish Study of Optimal Acute Treatment of Patients with ST-segment Elevation Myocardial Infarction - Ischaemic Postconditioning (DANAMI-3-iPOST) did not show improved clinical outcome in patients with ST-segment elevation myocardial infarction (STEMI) treated with ischaemic postconditioning. However, the use of thrombectomy was frequent and thrombectomy may in itself diminish the effect of ischaemic postconditioning. We evaluated the effect of ischaemic postconditioning in patients included in DANAMI-3-iPOST stratified by the use of thrombectomy.

METHODS

Patients with STEMI were randomised to conventional primary percutaneous coronary intervention (PCI) or ischaemic postconditioning plus primary PCI. The primary endpoint was a combination of all-cause mortality and hospitalisation for heart failure.

RESULTS

From March 2011 until February 2014, 1234 patients were included with a median follow-up period of 35 (interquartile range 28 to 42) months. There was a significant interaction between ischaemic postconditioning and thrombectomy on the primary endpoint (p=0.004). In patients not treated with thrombectomy (n=520), the primary endpoint occurred in 33 patients (10%) who underwent ischaemic postconditioning (n=326) and in 35 patients (18%) who underwent conventional treatment (n=194) (adjusted hazard ratio (HR) 0.55 (95%confidence interval (CI) 0.34 to 0.89), p=0.016). In patients treated with thrombectomy (n=714), there was no significant difference between patients treated with ischaemic postconditioning (n=291) and conventional PCI (n=423) on the primary endpoint (adjusted HR 1.18 (95% CI 0.62 to 2.28), p=0.62).

CONCLUSIONS

In this post-hoc study of DANAMI-3-iPOST, ischaemic postconditioning, in addition to primary PCI, was associated with reduced risk of all-cause mortality and hospitalisation for heart failure in patients with STEMI not treated with thrombectomy.

TRIAL REGISTRATION NUMBER

NCT01435408.

Computed tomography derived fractional flow reserve testing in stable patients with typical angina pectoris: influence on downstream rate of invasive coronary angiography

Aims

To assess the use of downstream coronary angiography (ICA) and short-term safety of frontline coronary CT angiography (CTA) with selective CT-derived fractional flow reserve (FFR_CT) testing in stable patients with typical angina pectoris.

Methods and results

Between 1 January 2016 and 30 June 2016 all patients (N = 774) referred to non-emergent ICA or coronary CTA at Aarhus University Hospital on a suspicion of CAD had frontline CTA performed. Downstream testing and treatment within 3 months and adverse events ≥90 days were registered. Patients were divided into two groups according to the presence of typical angina pectoris, which according to local practice would have resulted in referral to ICA, (low-intermediate-risk, n = 593 [76%]; high-risk, n = 181 [24%]) with mean pre-test probability of CAD of 31 ± 16% and 67 ± 16%, respectively. Coronary CTA was performed in 745 (96%) patients in whom FFR_CT was prescribed in 212 (28%) patients. In the high- vs. low-intermediate-risk group, ICA was cancelled in 75% vs. 91%. Coronary revascularization was performed more frequently in high-risk than in low-intermediate-risk patients, 76% vs. 52% (P = 0.03). Mean follow-up time was 157 ± 50 days. Serious clinical events occurred in four patients, but not in any patients with cancelled ICA by coronary CTA with selective FFR_CT testing.

Conclusion

Frontline coronary CTA with selective FFR_CT testing in stable patients with typical angina pectoris in real-world practice is associated with a high rate of safe cancellation of planned ICAs.

[Transcatheter aortic valve implantation in Denmark]

During the latest decade, transcatheter aortic valve implantation (TAVI) has evolved from being indicated only in patients with severe aortic stenosis and prohibitive or high surgical risk, to be an alternative to surgical aortic valve replacement in patients with intermediate surgical risk. Improvements of the peri-procedural management have resulted in marked reduction of complications and an increasing number of patients treated with TAVI every year in Denmark. By a minimalist approach, TAVI can be performed in local anesthaesia, with same day mobilisation and discharge within few days, without affecting the safety.

Distance to invasive heart centre, performance of acute coronary angiography, and angioplasty and associated outcome in out-of-hospital cardiac arrest: a nationwide study

Aims

To evaluate whether the distance from the site of event to an invasive heart centre, acute coronary angiography (CAG)/percutaneous coronary intervention (PCI) and hospital-level of care (invasive heart centre vs. local hospital) is associated with survival in out-of-hospital cardiac arrest (OHCA) patients.

Methods and results

Nationwide historical follow-up study of 41 186 unselected OHCA patients, in whom resuscitation was attempted between 2001 and 2013, identified through the Danish Cardiac Arrest Registry. We observed an increase in the proportion of patients receiving bystander CPR (18% in 2001, 60% in 2013, P < 0.001), achieving return of spontaneous circulation (ROSC) (10% in 2001, 29% in 2013, P < 0.001) and being admitted directly to an invasive centre (26% in 2001, 45% in 2013, P < 0.001). Simultaneously, 30-day survival rose from 5% in 2001 to 12% in 2013, P < 0.001. Among patients achieving ROSC, a larger proportion underwent acute CAG/PCI (5% in 2001, 27% in 2013, P < 0.001). The proportion of patients undergoing acute CAG/PCI annually in each region was defined as the CAG/PCI index. The following variables were associated with lower mortality in multivariable analyses: direct admission to invasive heart centre (HR 0.91, 95% CI: 0.89-0.93), CAG/PCI index (HR 0.33, 95% CI: 0.25-0.45), population density above 2000 per square kilometre (HR 0.94, 95% CI: 0.89-0.98), bystander CPR (HR 0.97, 95% CI: 0.95-0.99) and witnessed OHCA (HR 0.87, 95% CI: 0.85-0.89), whereas distance to the nearest invasive centre was not associated with survival.

Conclusion

Admission to an invasive heart centre and regional performance of acute CAG/PCI were associated with improved survival in OHCA patients, whereas distance to the invasive centre was not. These results support a centralized strategy for immediate post-resuscitation care in OHCA patients.

Evaluation of Coronary Artery Stenosis by Quantitative Flow Ratio During Invasive Coronary Angiography: The WIFI II Study (Wire-Free Functional Imaging II)

BACKGROUND

Quantitative flow ratio (QFR) is a novel diagnostic modality for functional testing of coronary artery stenosis without the use of pressure wires and induction of hyperemia. QFR is based on computation of standard invasive coronary angiographic imaging. The purpose of WIFI II (Wire-Free Functional Imaging II) was to evaluate the feasibility and diagnostic performance of QFR in unselected consecutive patients.

METHODS AND RESULTS

WIFI II was a predefined substudy to the Dan-NICAD study (Danish Study of Non-Invasive Diagnostic Testing in Coronary Artery Disease), referring 362 consecutive patients with suspected coronary artery disease on coronary computed tomographic angiography for diagnostic invasive coronary angiography. Fractional flow reserve (FFR) was measured in all segments with 30% to 90% diameter stenosis. Blinded observers calculated QFR (Medis Medical Imaging bv, The Netherlands) for comparison with FFR. FFR was measured in 292 lesions from 191 patients. Ten (5%) and 9 patients (5%) were excluded because of FFR and angiographic core laboratory criteria, respectively. QFR was successfully computed in 240 out of 255 lesions (94%) with a mean diameter stenosis of 50±12%. Mean difference between FFR and QFR was 0.01±0.08. QFR correctly classified 83% of the lesions using FFR with cutoff at 0.80 as reference standard. The area under the receiver operating characteristic curve was 0.86 (95% confidence interval, 0.81-0.91) with a sensitivity, specificity, negative predictive value, and positive predictive value of 77%, 86%, 75%, and 87%, respectively. A QFR-FFR hybrid approach based on the present results enables wire-free and adenosine-free procedures in 68% of cases.

CONCLUSIONS

Functional lesion evaluation by QFR assessment showed good agreement and diagnostic accuracy compared with FFR. Studies comparing clinical outcome after QFR- and FFR-based diagnostic strategies are required.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT02264717.

Association of common genetic variants related to atrial fibrillation and the risk of ventricular fibrillation in the setting of first ST-elevation myocardial infarction

Background

Cohort studies have revealed an increased risk for ventricular fibrillation (VF) and sudden cardiac death (SCD) in patients with atrial fibrillation (AF). In this study, we hypothesized that single nucleotide polymorphisms (SNP) previously associated with AF may be associated with the risk of VF caused by first ST-segment elevation myocardial infarction (STEMI).

Methods

We investigated association of 24 AF-associated SNPs with VF in the prospectively assembled case–control study among first STEMI-patients of Danish ancestry.

Results

We included 257 cases (STEMI with VF) and 537 controls (STEMI without VF). The median age at index infarction was 60 years for the cases and 61 years for the controls (p = 0.100). Compared to the control group, the case group was more likely to be male (86% vs. 75%, p = 0.001), have a history of AF (7% vs. 2%, p = 0.006) or hypercholesterolemia (39% vs. 31%, p = 0.023), and a family history of sudden death (40% vs. 25%, p < 0.001). All 24 selected SNPs have previously been associated with AF. None of the 24 SNPs were associated with the risk of VF after adjustment for age and sex under additive genetic model of inheritance in the logistic regression model.

Conclusion

In this study, we found that the 24 AF-associated SNPs may not be involved in increasing the risk of VF. Larger VF cohorts and use of new next generation sequencing and epigenetic may in future identify additional AF and VF risk loci and improve our understanding of genetic pathways behind the two arrhythmias.

Randomized Comparison of a Biodegradable Polymer Ultrathin Strut Sirolimus-Eluting Stent With a Biodegradable Polymer Biolimus-Eluting Stent in Patients Treated With Percutaneous Coronary Intervention: The SORT OUT VII Trial

BACKGROUND

Coronary drug-eluting stents with biodegradable polymers have been designed to improve safety and efficacy.

METHODS AND RESULTS

The Scandinavian Organization for Randomized Trials With Clinical Outcome (SORT OUT) VII trial-a large-scale registry-based randomized, multicenter, single-blind, 2-arm, noninferiority trial-compared 2 biodegradable polymer drug-eluting stents: the thin-strut cobalt-chromium sirolimus-eluting Orsiro stent and the stainless steel biolimus-eluting Nobori stent in an all-comer patient population. The primary end point target lesion failure was a composite of cardiac death, myocardial infarction (not related to other than index lesion), or target lesion revascularization within 1 year, analyzed by intention to treat (noninferiority margin of 3.0%). Clinically driven event detection based on Danish registries was used. A total of 1261 patients were assigned to receive the sirolimus-eluting stent (1590 lesions) and 1264 patients to the biolimus-eluting stent (1588 lesions). At 1 year, the composite end point target lesion failure occurred in 48 patients (3.8%) in the sirolimus-eluting group and in 58 patients (4.6%) in the biolimus-eluting group (absolute risk difference, -0.78% [upper limit of 1-sided 95% confidence interval, 0.61%]; P<0.0001). Rates of definite stent thrombosis occurred in 5 (0.4%) of the sirolimus-eluting group compared with 15 (1.2%) biolimus-eluting stent-treated patients (rate ratio, 0.33; 95% confidence interval, 0.12-0.92; P=0.034), which largely was attributable to a lower risk of subacute definite stent thrombosis: 0.1% versus 0.6% (rate ratio, 0.12; 95% confidence interval, 0.02-1.00; P=0.05).

CONCLUSIONS

The thin-strut sirolimus-eluting Orsiro stent was noninferior to the biolimus-eluting Nobori stent in unselected patients for target lesion failure at 1 year.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01879358.

Randomized Comparison of a Biodegradable Polymer Ultrathin Strut Sirolimus-Eluting Stent With a Biodegradable Polymer Biolimus-Eluting Stent in Patients Treated With Percutaneous Coronary Intervention: The SORT OUT VII Trial

BACKGROUND

Coronary drug-eluting stents with biodegradable polymers have been designed to improve safety and efficacy.

METHODS AND RESULTS

The Scandinavian Organization for Randomized Trials With Clinical Outcome (SORT OUT) VII trial-a large-scale registry-based randomized, multicenter, single-blind, 2-arm, noninferiority trial-compared 2 biodegradable polymer drug-eluting stents: the thin-strut cobalt-chromium sirolimus-eluting Orsiro stent and the stainless steel biolimus-eluting Nobori stent in an all-comer patient population. The primary end point target lesion failure was a composite of cardiac death, myocardial infarction (not related to other than index lesion), or target lesion revascularization within 1 year, analyzed by intention to treat (noninferiority margin of 3.0%). Clinically driven event detection based on Danish registries was used. A total of 1261 patients were assigned to receive the sirolimus-eluting stent (1590 lesions) and 1264 patients to the biolimus-eluting stent (1588 lesions). At 1 year, the composite end point target lesion failure occurred in 48 patients (3.8%) in the sirolimus-eluting group and in 58 patients (4.6%) in the biolimus-eluting group (absolute risk difference, -0.78% [upper limit of 1-sided 95% confidence interval, 0.61%]; P<0.0001). Rates of definite stent thrombosis occurred in 5 (0.4%) of the sirolimus-eluting group compared with 15 (1.2%) biolimus-eluting stent-treated patients (rate ratio, 0.33; 95% confidence interval, 0.12-0.92; P=0.034), which largely was attributable to a lower risk of subacute definite stent thrombosis: 0.1% versus 0.6% (rate ratio, 0.12; 95% confidence interval, 0.02-1.00; P=0.05).

CONCLUSIONS

The thin-strut sirolimus-eluting Orsiro stent was noninferior to the biolimus-eluting Nobori stent in unselected patients for target lesion failure at 1 year.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01879358.

[Extracorporeal cardiopulmonary resuscitation for patients with out-of-hospital refractory cardiac arrest]

Out-of-hospital cardiac arrest is associated with high mortality and morbidity. Treatment options remain few in refractory cases, but extracorporeal cardiopulmonary resuscitation (eCPR) is increasingly applied to improve the outcome. This article summarizes the use, experience and outcome of eCPR focussing on current knowledge of criteria for selection of relevant patients for treatment.

A Common Variant in SCN5A and the Risk of Ventricular Fibrillation Caused by First ST-Segment Elevation Myocardial Infarction

BACKGROUND

Several common genetic variants have been associated with either ventricular fibrillation (VF) or sudden cardiac death (SCD). However, replication efforts have been limited. Therefore, we aimed to analyze whether such variants may contribute to VF caused by first ST-elevation myocardial infarction (STEMI).

METHODS

We analyzed 27 single nucleotide polymorphisms (SNP) previously associated with SCD/VF in other cohorts, and examined whether these SNPs were associated with VF caused by first STEMI in the GEnetic causes of Ventricular Arrhythmias in patients with first ST-elevation Myocardial Infarction (GEVAMI) study on ethnical Danes. The GEVAMI study is a prospective case-control study involving 257 cases (STEMI with VF) and 537 controls (STEMI without VF).

RESULTS

Of the 27 candidate SNPs, one SNP (rs11720524) located in intron 1 of SCN5A which was previously associated with SCD was significantly associated with VF caused by first STEMI. The major C-allele of rs11720524 was present in 64% of the cases and the C/C genotype was significantly associated with VF with an odds ratio (OR) of 1.87 (95% CI: 1.12-3.12; P = 0.017). After controlling for clinical differences between cases and controls such as age, sex, family history of sudden death, alcohol consumption, previous atrial fibrillation, statin use, angina, culprit artery, and thrombolysis in myocardial infarction (TIMI) flow, the C/C genotype of rs11720524 was still significantly associated with VF with an OR of 1.9 (95% CI: 1.05-3.43; P = 0.032). Marginal associations with VF were also found for rs9388451 in HEY2 gene. The CC genotype showed an insignificant risk for VF with OR = 1.50 (95% CI: 0.96-2.40; P = 0.070).

CONCLUSION

One common intronic variant in SCN5A suggested an association with VF caused by first STEMI. Further studies into the functional abnormalities associated with the noncoding variant in SCN5A may lead to important insights into predisposition to VF during STEMI.