Scar border zone mass and presence of border zone channels assessed with cardiac magnetic resonance imaging are associated with ventricular arrhythmia in patients with ST-segment elevation myocardial infarction.

AIMS: Late gadolinium enhancement cardiac magnetic resonance (CMR) permits characterization of left ventricular ischaemic scars. We aimed to evaluate if scar core mass, border zone (BZ) mass, and BZ channels are risk markers for subsequent ventricular arrhythmia (VA) in ST-segment elevation myocardial infarction (STEMI). METHODS AND RESULTS: A sub-study of the DANish Acute Myocardial Infarction-3 multi-centre trial and Danegaptide phase II proof-of-concept clinical trial in which a total of 843 STEMI patients had a 3-month follow-up CMR. Of these, 21 patients subsequently experienced VA during 100 months of follow-up and were randomly matched 1:5 with 105 controls. A VA event was defined as: ventricular tachycardia, ventricular fibrillation, or sudden cardiac death. Ischaemic scar characteristics were automatically detected by specialized software. We included 126 patients with a median left ventricular ejection fraction of 51.0 ± 11.6% in cases with VA vs. 55.5 ± 8.5% in controls (P = 0.10). Cases had a larger mean BZ mass and more often BZ channels compared to controls [BZ mass: 17.2 ± 10.3 g vs. 10.3 ± 6.0 g; P = 0.0002; BZ channels: 17 (80%) vs. 44 (42%); P = 0.001]. A combination of ≥17.2 g BZ mass and the presence of BZ channels was five times more prevalent in cases vs. controls (P ≤ 0.00001) with an odds ratio of 9.40 (95% confidence interval 3.26-27.13; P ≤ 0.0001) for VA. This identified cases with 52% sensitivity and 90% specificity. CONCLUSION(S): Scar characterization with CMR indicates that a combination of ≥17.2 g BZ mass and the presence of BZ channels had the strongest association with subsequent VA in STEMI patients. CLINICALTRIALS.GOV: Unique identifier: NCT01435408 (DANAMI 3-iPOST and DANAMI 3-DEFER), NCT01960933 (DANAMI 3-PRIMULTI), and NCT01977755 (Danegaptide).

The Incidence and Impact of Permanent Right Ventricular Infarction on Left Ventricular Infarct Size in Patients With Inferior ST-Segment Elevation Myocardial Infarction.

Mounting evidence shows that right ventricle (RV) function carries independent prognostic influence in various disease states. This study aimed to investigate the incidence and impact of permanent RV infarction in patients with inferior ST-segment elevation myocardial infarction (STEMI) and culprit lesion in the right coronary artery (RCA). In this substudy of the DANAMI-3 (DANish Study of Optimal Acute Treatment of Patients with ST-segment Elevation Myocardial Infarction) trial, cardiac magnetic resonance was performed in 291 patients at day 1 and follow-up 3 months after primary percutaneous coronary intervention of 674 patients with STEMI with the culprit lesion in the RCA. Final infarct was assessed using late gadolinium enhancement on cardiac magnetic resonance at 3 months. Patients with permanent RV infarction (20%) had lower ventricular function at follow-up; RV ejection fraction (EF) 47% ±6 versus 50% ± 5 (p <0.005) and left ventricular (LV) EF 56% ± 8 versus 60% ± 9 (p <0.006). Furthermore, patients with permanent RV infarction had a higher incidence of microvascular obstruction 39 (67%) versus 81 (39%) (p <0.001), larger final LV infarct size 16% ±8 versus 10% ± 8 (p <0.001) and larger LV area at risk 33% ± 10 versus 29% ± 9 (p <0.001). Permanent RV infarction was an independent predictor of final LV infarct size (p <0.001) but was not associated with LVEF (ß = -0.0; p = 0.13) in multivariable analyses. In conclusion, permanent RV infarction was seen in 20% of patients with inferior STEMI and culprit lesion in RCA and independently predicted final LV infarct size. However, permanent RV infarction did not predict overall LV function. LGE was used to detect infarct location and quantify infarct size.17 LGE in RV free wall on follow-up CMR was considered as permanent infarction. LGE images were obtained 10 minutes after intravenous injection of 0.1-mmol/kg body weight of gadolinium-based contrast (Gadovist; Bayer Schering, Berlin, Germany) using an electrocardiogram (ECG)-triggered inversion-recovery sequence. The inversion time was adjusted to null the signal from the normal myocardium. Short-axis images were acquired from the atrioventricular plane to the apex with adjacent 8-mm slices. The remaining protocol has been described previously.16.

Cardiovascular magnetic resonance characteristics and clinical outcomes of patients with ST-elevation myocardial infarction and no standard modifiable risk factors-A DANAMI-3 substudy.

Introduction: A higher 30-day mortality has been observed in patients with first-presentation ST elevation myocardial infarction (STEMI) who have no standard modifiable cardiovascular risk factors (SMuRFs), i. e., diabetes, hypertension, hyperlipidemia, and current smoker. In this study, we evaluate the clinical outcomes and CMR imaging characteristics of patients with and without SMuRFs who presented with first-presentation STEMI. Methods: Patients from the Third DANish Study of Acute Treatment of Patients With ST-Segment Elevation Myocardial Infarction (DANAMI-3) with first-presentation STEMI were classified into those with no SMuRFs vs. those with at least one SMuRF. Results: We identified 2,046 patients; 283 (14%) SMuRFless and 1,763 (86%) had >0 SMuRF. SMuRFless patients were older (66 vs. 61 years, p < 0.001) with more males (84 vs. 74%, p < 0.001), more likely to have left anterior descending artery (LAD) as the culprit artery (50 vs. 42%, p = 0.009), and poor pre-PCI (percutaneous coronary intervention) TIMI (thrombolysis in myocardial infarction) flow ≤1 (78 vs. 64%; p < 0.001). There was no difference in all-cause mortality, non-fatal reinfarction, or hospitalization for heart failure at 30 days or at long-term follow-up. CMR imaging was performed on 726 patients. SMuRFless patients had larger acute infarct size (17 vs. 13%, p = 0.04) and a smaller myocardial salvage index (42 vs. 50%, p = 0.02). These differences were attenuated when the higher LAD predominance and/or TIMI 0-1 flow were included in the model. Conclusion: Despite no difference in 30-day mortality, SMuRFless patients had a larger infarct size and a smaller myocardial salvage index following first-presentation STEMI. This association was mediated by a larger proportion of LAD culprits and poor TIMI flow pre-PCI. Clinical trial registration: clinicaltrials.gov, unique identifier: NCT01435408 (DANAMI 3-iPOST and DANAMI 3-DEFER) and NCT01960933 (DANAMI 3-PRIMULTI).

Angiographic outcome in patients treated with deferred stenting after ST-segment elevation myocardial infarction-results from DANAMI-3-DEFER.

AIMS: Stent implantation during primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI) occasionally results in flow disturbances and distal embolization, which may cause adverse clinical outcomes. Deferred stent implantation seems to reduce the impairment on myocardial function, although the mechanisms have not been clarified. We sought to evaluate whether deferred stenting could reduce flow disturbance in patients treated with primary PCI. METHODS AND RESULTS: Patients with STEMI included in the DANAMI-3-DEFER trial were randomized to deferred versus immediate stent implantation. The primary and secondary outcomes of this substudy were the incidences of slow/no reflow and distal embolization. A total of 1205 patients were included. Deferred stenting (n = 594) resulted in lower incidences of distal embolization [odds ratio (OR) 0.67, 95% confidence interval (CI) 0.46-0.98, P = 0.040] and slow/no reflow (OR 0.60, 95%CI 0.37-0.97, P = 0.039). In high-risk subgroups, the protective effect was greatest in patients >65 years of age (slow/no reflow: OR 0.36, 95% CI 0.17-0.72, P = 0.004 and distal embolization: OR 0.34, 95% CI 0.18-0.63, P = 0.001), in patients presenting with occluded culprit artery at admission (slow/no reflow: OR 0.33, 95% CI 0.16-0.65, P = 0.001 and distal embolization: OR 0.54, 95% CI 0.31-0.96, P = 0.036) and in patients with thrombus grade >3 (slow/no reflow: OR 0.37, 95% CI 0.20-0.67, P = 0.001 and distal embolization: OR 0.39, 95% CI 0.24-0.64, P < 0.001) with a significant P for interaction for all. CONCLUSION: Deferred stent implantation reduces the incidences of slow/no reflow and distal embolization, especially in older patients and in those with total coronary occlusion or high level of thrombus burden.

Clinical outcomes of no stenting in patients with ST-segment elevation myocardial infarction undergoing deferred primary percutaneous coronary intervention.

BACKGROUND: ST-segment elevation myocardial infarction (STEMI) is treated with stenting, but the underlying stenosis is often not severe, and stenting may potentially be omitted. AIMS: The aim of the study was to investigate outcomes of patients with STEMI treated with percutaneous coronary intervention (PCI) without stenting. METHODS: Patients were identified through the DANAMI-3-DEFER study. Stenting was omitted in the patients with stable flow after initial PCI and no significant residual stenosis on the deferral procedure, who were randomised to deferred stenting. These patients were compared to patients randomised to conventional PCI treated with immediate stenting. The primary endpoint was a composite of all-cause mortality, recurrent myocardial infarction (MI), and target vessel revascularisation (TVR). RESULTS: Of 603 patients randomised to deferred stenting, 84 were treated without stenting, and in patients randomised to conventional PCI (n=612), 590 were treated with immediate stenting. Patients treated with no stenting had a median stenosis of 40%, median vessel diameter of 2.9 mm, and median lesion length of 11.4 mm. During a median follow-up of 3.4 years, the composite endpoint occurred in 14% and 16% in the no and immediate stenting groups, respectively (unadjusted hazard ratio [HR] 0.87, 95% confidence interval [CI]: 0.48-1.60; p=0.66). The association remained non-significant after adjusting for confounders (adjusted HR 0.53, 95% CI: 0.22-1.24; p=0.14). The rates of TVR and recurrent MI were 2% vs 4% (p=0.70) and 4% vs 6% (p=0.43), respectively. CONCLUSIONS: Patients with STEMI, with no significant residual stenosis and stable flow after initial PCI, treated without stenting, had comparable event rates to patients treated with immediate stenting.

Comparison of Effect of Ischemic Postconditioning on Cardiovascular Mortality in Patients With ST-Segment Elevation Myocardial Infarction Treated With Primary Percutaneous Coronary Intervention With Versus Without Thrombectomy.

In patients with ST-segment elevation myocardial infarction (STEMI), ischemic postconditioning (iPOST) have shown ambiguous results in minimizing reperfusion injury. Previous findings show beneficial effects of iPOST in patients with STEMI treated without thrombectomy. However, it remains unknown whether the cardioprotective effect of iPOST in these patients persist on long term. In the current study, all patients were identified through the DANAMI-3-iPOST database. Patients were randomized to conventional primary percutaneous coronary intervention (PCI) or iPOST in addition to PCI. Cumulative incidence rates were calculated, and multivariable analyses stratified according to thrombectomy use were performed. The primary end point was a combination of cardiovascular mortality and hospitalization for heart failure. From 2011 to 2014, 1,234 patients with STEMI were included with a median follow-up of 4.8 years. In patients treated without thrombectomy (n = 520), the primary end point occurred in 15% (48/326) in the iPOST group and in 22% (42/194) in the conventional group (unadjusted hazard ratio [HR] 0.62, 95% confidence interval [CI] 0.41 to 0.94, p = 0.023). In adjusted Cox analysis, iPOST remained associated with reduced long-term risk of cardiovascular mortality (HR 0.53, 95% CI 0.29 to 0.97, p = 0.039). In patients treated with thrombectomy (n = 714), there was no significant difference between iPOST (17%, 49/291) and conventional treatment (17%, 72/423) on the primary end point (unadjusted HR 1.01, 95% CI 0.70 to 1.45, p = 0.95). During a follow-up of nearly 5 years, iPOST reduced long-term occurrence of cardiovascular mortality and hospitalization for heart failure in patients with STEMI treated with PCI but without thrombectomy.

Ischemia From Nonculprit Stenoses Is Not Associated With Reduced Culprit Infarct Size in Patients with ST-Segment-Elevation Myocardial Infarction.

BACKGROUND: In patients with ST-segment-elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention, reperfusion injury accounts for a significant fraction of the final infarct size, which is directly related to patient prognosis. In animal studies, brief periods of ischemia in noninfarct-related (nonculprit) coronary arteries protect the culprit myocardium via remote ischemic preconditioning. Positive fractional flow reserve (FFR) documents functional significant coronary nonculprit stenosis, which may offer remote ischemic preconditioning of the culprit myocardium. The aim of the study was to investigate the association between functional significant, multivessel disease (MVD) and reduced culprit final infarct size or increased myocardial salvage (myocardial salvage index [MSI]) in a large contemporary cohort of STEMI patients. METHODS: Cardiac magnetic resonance was performed in 610 patients with STEMI at day 1 and 3 months after primary percutaneous coronary intervention. Patients were stratified into 3 groups according to FFR measurements in nonculprit stenosis (if any): angiographic single vessel disease (SVD), FFR nonsignificant MVD (functional SVD), or FFR-significant, functional MVD. RESULTS: A total of 431 (71%) patients had SVD, 35 (6%) had functional SVD, and 144 (23%) had functional MVD. There was no difference in final infarct size (mean infarct size [%left ventricular mass] SVD, 9±3%; functional SVD, 9±3%; and functional MVD, 9±3% [P=0.82]) or in MSI between groups (mean MSI [%left] SVD, 66±23%; functional SVD, 68±19%; and functional MVD, 69±19% [P=0.62]). In multivariable analyses, functional MVD was not associated with larger MSI (P=0.56) or smaller infarct size (P=0.55). CONCLUSIONS: Functional MVD in nonculprit myocardium was not associated with reduced culprit final infarct size or increased MSI following STEMI. This is important knowledge for future studies examining a cardioprotective treatment in patients with STEMI, as a possible confounding effect of FFR-significant, functional MVD can be discarded. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01435408 (DANAMI 3-iPOST and DANAMI 3-DEFER) and NCT01960933 (DANAMI 3-PRIMULTI).

Impact of age on reperfusion success and long-term prognosis in ST-segment elevation myocardial infarction - A cardiac magnetic resonance imaging study.

BACKGROUND: Coronary collateral circulation and conditioning from remote ischemic coronary territories may protect culprit myocardium in the elderly, and younger STEMI patients could suffer from larger infarcts. We evaluated the impact of age on myocardial salvage and long-term prognosis in a contemporary STEMI cohort. METHODS: Of 1603 included STEMI patients 807 underwent cardiac magnetic resonance. To assess the impact of age on infarct size and left ventricular ejection fraction (LVEF) as well as the composite endpoint of death and re-hospitalization for heart failure we stratified the patients by an age cut-off of 60 years. RESULTS: Younger STEMI patients had smaller final infarcts (10% vs. 12%, P = 0.012) and higher final LVEF (60% vs. 58%, P = 0.042). After adjusting for multiple potential confounders age did not remain significantly associated with infarct size and LVEF. During 4-year follow-up, the composite endpoint occurred less often in the young (3.2% vs. 17.2%; P < 0.001) with a univariate hazard ratio of 5.77 (95% CI, 3.75-8.89; p < 0.001). Event estimates of 4 subgroups (young vs. elderly and infarct size beyond vs. below median) showed a gradual increase in the occurrence of the composite endpoint depending on both age and acute infarct size (log-rank p < 0.001). CONCLUSION: Having a STEMI after entering the seventh decade of life more than quadrupled the risk of future death or re-hospitalization for heart failure. Risk of death and re-hospitalization depended on both advanced age and infarct size, albeit no substantial difference was found in infarct size, LVEF and salvage potential between younger and elderly patients with STEMI.

Degree of ST-segment elevation in patients with STEMI reflects the acute ischemic burden and the salvage potential.

BACKGROUND: ST-segment elevation myocardial infarction (STEMI) is clinically diagnosed by significant ST-segment elevation (STE) in the electrocardiogram (ECG). The importance of the sum of significant ST-segment elevation (∑STE) before primary percutaneous coronary intervention (PPCI) - considered an indicator of the degree of ischemia - is sparse. We evaluated the association of ∑STE before PPCI with respect to area at risk, infarct size and myocardial salvage. METHODS: A total of 503 patients with STEMI and available cardiac magnetic resonance (CMR) were included. CMR was performed at day 1 (interquartile range [IQR], 1-1) and at follow-up at day 92 (IQR, 88-96). The ECG before PPCI with the most prominent STE was used for analysis. RESULTS: ∑STE divided into quartiles were progressive linearly associated with area at risk (p < 0.001), final infarct size (p < 0.001) and extent of microvascular obstruction (p < 0.001) and inverse linearly associated with final myocardial salvage (p < 0.001). Similar results were found for linear regression analyses. However, ∑STE was not associated with final myocardial salvage in patients with pre-PCI TIMI (thrombolysis in myocardial infarction) flow 0/1 (p = 0.24) in contrast to patients with pre-PCI TIMI flow 2/3 (p ≤ 0.001). CONCLUSION: In patients with STEMI presenting within 12 h of symptom onset, the degree of STE in the ECG before PPCI is a marker of the extent of myocardium at risk that in turn affects the infarct size in patients with pre-PCI TIMI flow 0/1, whereas the degree of STE in patients with pre-PCI TIMI flow 2/3 is a marker of the extent of the myocardium at risk as well as myocardial salvage - both affecting the myocardial damage.

Usefulness of High Sensitivity Troponin T to Predict Long-Term Left Ventricular Dysfunction After ST-Elevation Myocardial Infarction.

Guidelines recommend the use of transthoracic echocardiography (TTE) and clinical scores to risk stratify patients after ST-elevation myocardial infarction (STEMI). High sensitivity troponin T (hs-cTnT) is predictive of outcome after STEMI but the predictive value of hs-cTnT relative to other risk assessment tools has not been established. We aimed to compare the predictive value of hs-cTnT to other risk assessment tools in patients with STEMI. A subset of 578 patients with STEMI were included in this post-hoc study from the Third DANish Study of Optimal Acute Treatment of Patients with ST-segment Elevation Myocardial Infarction trial. Patients underwent cardiac magnetic resonance imaging (CMR) during index hospitalization as well as TTE at 1 year after their STEMI. The predictive value of hs-cTnT was compared with CKMB, infarct size (IS)/left ventricular ejection fraction (LVEF) assessed with CMR, LVEF assessed at discharge with TTE and the Global Registry of Acute Coronary Events (GRACE) and Thrombolysis in Myocardial Infarction (TIMI) risk-scores. The primary outcome was LV systolic dysfunction defined as LVEF ≤40% after 1 year on TTE. The area under the receiver operating characteristic curve analyses showed no significant difference between hs-cTnT and early CMR-assessed IS or LVEF in predicting subsequent LVEF ≤40%. Area under the curve for hs-cTnT was 0.82, 0.85 for IS (p = 0.22), and 0.87 for LVEF (p = 0.23). For predischarge TTE-assessed LVEF, the value was 0.85 (p = 0.45), 0.63 for creatine kinase-MB (p <0.001), 0.61 for the GRACE score (p <0.001), and 0.70 for the TIMI score (p = 0.02). A peak hs-cTnT value <3,500 ng/L ruled out LVEF ≤40% with probability of 98%. In conclusion, in patients presenting with STEMI undergoing PCI, hs-cTnT level strongly predicted long-term LV dysfunction and could be used as a clinical risk stratification tool to identify patients at high risk of progressing to LV dysfunction due to its general availability and high-predictive accuracy.

Infarct size following loading with Ticagrelor/Prasugrel versus Clopidogrel in ST-segment elevation myocardial infarction.

BACKGROUND: Treatment with newer direct-acting anti-platelet drugs (Ticagrelor and Prasugrel) prior to primary percutaneous coronary intervention (PCI) is associated with improved outcome in patients with ST-segment elevation myocardial infarction (STEMI) when compared with Clopidogrel. We compared infarct size following treatment with Ticagrelor/Prasugrel versus Clopidogrel in the DANish trial in Acute Myocardial Infarction (DANAMI-3) population of STEMI patients treated with primary PCI. METHODS AND RESULTS: Patients were loaded with Clopidogrel, Ticagrelor or Prasugrel in the ambulance before primary PCI. Infarct size and myocardial salvage index were calculated using cardiac magnetic resonance (CMR) during index admission and at three-month follow-up. Six-hundred-and-ninety-three patients were included in this analysis. Clopidogrel was given to 351 patients and Ticagrelor/Prasugrel to 342 patients. The groups were generally comparable in terms of baseline and procedural characteristics. Median infarct size at three-month follow-up was 12.9% vs 10.0%, in patients treated with Clopidogrel and Ticagrelor/ Prasugrel respectively (p < 0.001), and myocardial salvage index was 66% vs 71% (p < 0.001). Results remained significant in a multiple regression model (p < 0.001). CONCLUSIONS: Pre-hospital loading with Ticagrelor or Prasugrel compared to Clopidogrel, was associated with smaller infarct size and larger myocardial salvage index at three-month follow-up in patients with STEMI treated with primary PCI.

Clinical outcome following late reperfusion with percutaneous coronary intervention in patients with ST-segment elevation myocardial infarction.

BACKGROUND: Up to 40% of patients with ST-segment elevation myocardial infarction (STEMI) present later than 12 hours after symptom onset. However, data on clinical outcomes in STEMI patients treated with primary percutaneous coronary intervention 12 or more hours after symptom onset are non-existent. We evaluated the association between primary percutaneous coronary intervention performed later than 12 hours after symptom onset and clinical outcomes in a large all-comer contemporary STEMI cohort. METHODS: All STEMI patients treated with primary percutaneous coronary intervention in eastern Denmark from November 2009 to November 2016 were included and stratified by timing of the percutaneous coronary intervention. The combined clinical endpoint of all-cause mortality and hospitalisation for heart failure was identified from nationwide Danish registries. RESULTS: We included 6674 patients: 6108 (92%) were treated less than 12 hours and 566 (8%) were treated 12 or more hours after symptom onset. During a median follow-up period of 3.8 (interquartile range 2.3-5.6) years, 30-day, one-year and long-term cumulative rates of the combined endpoint were 11%, 17% and 25% in patients treated 12 or fewer hours and 21%, 29% and 37% in patients treated more than 12 hours (P<0.001 for all) after symptom onset. Late presentation was independently associated with an increased risk of an adverse clinical outcome (hazard ratio 1.42, 95% confidence interval 1.22-1.66; P<0.001). CONCLUSIONS: Increasing duration from symptom onset to primary percutaneous coronary intervention was associated with an increased risk of an adverse clinical outcome in patients with STEMI, especially when the delay exceeded 12 hours.

Electrocardiogram to predict reperfusion success in late presenters with ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention.

BACKGROUND: Clinical decision-making in patients with ST-segment elevation myocardial infarction (STEMI) presenting beyond 12 h of symptom onset (late presenters) is challenging. However, the electrocardiogram (ECG) may provide helpful information. We investigated the association between three ECG-scores and myocardial salvage and infarct size in late presenters treated with primary percutaneous coronary intervention (primary PCI). METHODS: Sixty-six patients with STEMI and ongoing symptoms presenting 12-72 h after symptom onset were included. Cardiac magnetic resonance was performed at day 1 (interquartile range [IQR], 1-1) and at follow-up at day 93 (IQR, 90-98). The pre-PCI ECG was analyzed for the presence of pathological QW (early QW) as well as Anderson-Wilkins acuteness score (AW-score), the classic Sclarovsky-Birnbaum Ischemia Grading System (classic SB-IG-score) and a modified SB-IG-score including any T-wave morphologies. RESULTS: Early QW was associated with a larger myocardium at risk (39 ± 12 versus 33 ± 12; p = 0.030) and final infarct size (20 ± 11 versus 14 ± 9; p = 0.021) as well as a numerical lower final myocardial salvage (0.52 ± 0.19 versus 0.61 ± 0.23; p = 0.09). The association with final infarct size disappeared after adjusting for myocardium at risk. An AW-score < 3 showed a trend towards a larger final infarct size (18 ± 11 versus 11 ± 11; p = 0.08) and was not associated with salvage index (0.55 ± 0.20 versus 0.65 ± 0.30; p = 0.23). The classic and modified SB-IG-score were not associated with final infarct size (modified SB-IG-score, 17 ± 10 versus 21 ± 13; p = 0.28) or final myocardial salvage (0.53 ± 0.20 versus 0.53 ± 0.26; p = 0.96). CONCLUSION: Of three well-established ECG-scores only early QW and AW-score < 3 showed association with myocardium at risk and infarct size to some extent, but the association with myocardial salvage was weak. Hence, neither of the three investigated ECG-scores are sufficient to guide clinical decision-making in patients with STEMI and ongoing symptoms presenting beyond 12 h of symptom onset.

Clinical outcome following late reperfusion with percutaneous coronary intervention in patients with ST-segment elevation myocardial infarction.

BACKGROUND: Up to 40% of patients with ST-segment elevation myocardial infarction (STEMI) present later than 12 hours after symptom onset. However, data on clinical outcomes in STEMI patients treated with primary percutaneous coronary intervention 12 or more hours after symptom onset are non-existent. We evaluated the association between primary percutaneous coronary intervention performed later than 12 hours after symptom onset and clinical outcomes in a large all-comer contemporary STEMI cohort. METHODS: All STEMI patients treated with primary percutaneous coronary intervention in eastern Denmark from November 2009 to November 2016 were included and stratified by timing of the percutaneous coronary intervention. The combined clinical endpoint of all-cause mortality and hospitalisation for heart failure was identified from nationwide Danish registries. RESULTS: We included 6674 patients: 6108 (92%) were treated less than 12 hours and 566 (8%) were treated 12 or more hours after symptom onset. During a median follow-up period of 3.8 (interquartile range 2.3-5.6) years, 30-day, one-year and long-term cumulative rates of the combined endpoint were 11%, 17% and 25% in patients treated 12 or fewer hours and 21%, 29% and 37% in patients treated more than 12 hours (P<0.001 for all) after symptom onset. Late presentation was independently associated with an increased risk of an adverse clinical outcome (hazard ratio 1.42, 95% confidence interval 1.22-1.66; P<0.001). CONCLUSIONS: Increasing duration from symptom onset to primary percutaneous coronary intervention was associated with an increased risk of an adverse clinical outcome in patients with STEMI, especially when the delay exceeded 12 hours.

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.

Early Q-wave morphology in prediction of reperfusion success in patients with ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention - A cardiac magnetic resonance imaging study.

BACKGROUND: Pathological Q-wave (QW) in the electrocardiogram (ECG) before primary percutaneous coronary intervention (primary PCI) is a strong prognostic marker in patients with ST-segment elevation myocardial infarction (STEMI). However, current binary QW criteria are either not clinically applicable or have a lack of diagnostic performance. Accordingly, we evaluated the association between duration, depth and area of QW and markers of the effect of reperfusion (reperfusion success). METHODS: A total of 516 patients with their first STEMI had obtained an ECG before primary PCI and an acute cardiac magnetic resonance imaging (CMR) at day 1 (interquartile range [IQR], 1-1) and at follow-up at day 92 (IQR, 89-96). The largest measurable QW in ECG was used for analysis of duration, depth and area of QW (QW morphology). The QW morphology was evaluated as a continuous variable in linear regression models and as a variable divided in four equally large groups. RESULTS: The QW morphology as four equally large groups was significantly associated with all CMR endpoints (p ≤ 0.001) and showed a linear relationship (p ≤ 0.001) with final infarct size (for QW duration, ß = 0.47; QW depth, ß = 0.41 and QW area, ß = 0.39), final infarct transmurality (for QW duration, ß = 0.36; QW depth, ß = 0.26 and QW area, ß = 0.23) and final myocardial salvage index (for QW duration, ß = -0.34; QW depth, ß = -0.26 and QW area, ß = -0.24). CONCLUSION: Although modest, the QW morphology in STEMI patients showed significant linear association with markers of reperfusion success. Hence, it is suggested that the term pathological is not used as a dichotomous parameter in patients with STEMI but rather evaluated on the basis of extent.

Fractional flow reserve-guided PCI in patients with and without left ventricular hypertrophy: a DANAMI-3-PRIMULTI substudy.

AIMS: The aim of this substudy was to investigate the correlation between fractional flow reserve (FFR) and diameter stenosis in patients with STEMI with and without left ventricular hypertrophy (LVH), and the influence of LVH on complete FFR-guided revascularisation versus culprit only, in terms of risk of clinical outcome. METHODS AND RESULTS: In this DANAMI-3-PRIMULTI substudy, 279 patients with STEMI had cardiac magnetic resonance (CMR) imaging for assessment of left ventricular mass index. Ninety-six patients had FFR evaluation of a non-culprit lesion. Diameter stenosis of the non-culprit lesion was determined with two-dimensional quantitative coronary analysis. The diameter stenosis (56.9% vs 54.3%, p=0.38) and FFR value (0.83 vs 0.85, p=0.34) were significantly correlated in both groups (Spearman's ρ=-0.40 and -0.41 without LVH and with LVH, respectively; p<0.001) but were not different between patients without and with LVH (p for interaction=0.87). FFR-guided complete revascularisation was associated with reduced risk of death, myocardial infarction or ischaemia-driven revascularisation both for patients without LVH (HR 0.42, 95% CI: 0.20-0.85) and for patients with LVH (HR 0.50, 95% CI: 0.17-1.47), with no interaction between the FFR-guided complete revascularisation and LVH (p for interaction=0.82). CONCLUSIONS: LVH did not interact with the correlation between diameter stenosis and FFR and did not modify the impact of complete revascularisation on the occurrence of subsequent clinical events.