Background: The invasive microvascular function indices, coronary flow reserve (CFR) and the index of microcirculatory resistance (IMR), exhibit a dynamic pattern after ST-segment–elevation myocardial infarction. The effects of microvascular injury on the evolution of the microvascular function and the prognostic significance of the evolution of microvascular function are unknown. We investigated the relationship between the temporal changes of CFR and IMR, and cardiovascular magnetic resonance-derived microvascular injury characteristics in reperfused ST-segment–elevation myocardial infarction patients, and their association with 1-month left ventricular ejection fraction and infarct size (IS). Methods: In 109 ST-segment–elevation myocardial infarction patients who underwent angiography for primary percutaneous coronary intervention (PPCI) and at 1-month follow-up, invasive assessment of CFR and IMR were performed in the culprit artery during both procedures. Cardiovascular magnetic resonance was performed 2 to 7 days after PPCI and at 1 month and provided assessment of left ventricular ejection fraction, IS, microvascular obstruction, and intramyocardial hemorrhage. Results: CFR and IMR significantly changed over 1 month (both, P <0.001). The absolute IMR change over 1 month (ΔIMR) showed association with both microvascular obstruction and intramyocardial hemorrhage presence (both, P =0.01). ΔIMR differed between patients with/without microvascular obstruction ( P =0.02) and with/without intramyocardial hemorrhage ( P =0.04) but not ΔCFR for both. ΔIMR demonstrated association with both left ventricular ejection fraction and IS at 1 month ( P 50% and extensive IS (the highest quartile). Conclusions: In reperfused ST-segment–elevation myocardial infarction patients, CFR and IMR significantly improved 1 month after PPCI; the temporal change in IMR is closely related to the presence/absence of microvascular damage and IS. ΔIMR exhibits a stronger association for 1-month functional outcome than post-PPCI CFR, IMR, or ΔCFR.

The PRISON IV trial investigated the next-generation sirolimus-eluting stent (SES) with ultra-thin struts and biodegradable polymer against the second-generation everolimus-eluting stent (EES) with thin struts and durable polymer in patients with successfully recanalised chronic total occlusions (CTO). In this study, we examined the secondary optical coherence tomography endpoints. The main PRISON IV trial randomised 330 patients to either SES or EES. At nine months, 281 (85%) patients underwent repeat angiography. Of these, 60 consecutive patients received optical coherence tomography divided over both stent groups. The mean number of struts analysed was 750±337 and 633±358 in SES and EES patients, respectively (p=0.07). The minimal lumen area, minimal stent area, maximal neointima area and neointimal thickness were comparable between the groups (4.8±2.1 and 4.4±1.5 mm2; 5.3±1.8 and 5.3±1.4 mm2; 2.5±2.0 and 2.2±1.5 mm2; 0.7±1.7 and 0.4±0.2 mm). The percentage of uncovered struts was higher with EES (6.2±7.5% and 11.9±13.4%, p=0.04), whereas the percentage of malapposed struts and mean number of coronary evaginations were significantly higher with SES (2.9±4.0% and 1.2±2.4%, p=0.02; 18.5±17.7 and 5.3±3.1, p=0.004). The optical coherence tomography findings of this substudy demonstrated improved strut coverage with ultra-thin strut SES with bioresorbable polymer compared to thin-strut EES with durable polymer in CTO. On the other hand, SES showed a higher rate of stent strut malappositon and coronary evaginations. The clinical relevance of these findings remains to be demonstrate

The effect of immediate coronary angiography and percutaneous coronary intervention (PCI) in patients who are successfully resuscitated after cardiac arrest in the absence of ST-segment elevation myocardial infarction (STEMI) on left ventricular function is currently unknown. This prespecified sub-study of a multicentre trial evaluated 552 patients, successfully resuscitated from out-of-hospital cardiac arrest without signs of STEMI. Patients were randomized to either undergo immediate coronary angiography or delayed coronary angiography, after neurologic recovery. All patients underwent PCI if indicated. The main outcomes of this analysis were left ventricular ejection fraction and end-diastolic and systolic volumes assessed by cardiac magnetic resonance imaging or echocardiography. Data on left ventricular function was available for 397 patients. The mean (± standard deviation) left ventricular ejection fraction was 45.2% (±12.8) in the immediate angiography group and 48.4% (±13.2) in the delayed angiography group (mean difference: -3.19; 95% confidence interval [CI], -6.75 to 0.37). Median left ventricular end-diastolic volume was 177 ml in the immediate angiography group compared to 169 ml in the delayed angiography group (ratio of geometric means: 1.06; 95% CI, 0.95-1.19). In addition, mean left ventricular end-systolic volume was 90 ml in the immediate angiography group compared to 78 ml in the delayed angiography group (ratio of geometric means: 1.13; 95% CI 0.97-1.32). In patients successfully resuscitated after out-of-hospital cardiac arrest and without signs of STEMI, immediate coronary angiography was not found to improve left ventricular dimensions or function compared with a delayed angiography strategy. Netherlands Trial Register number, NTR4973.

Importance: Several randomized clinical trials (RCTs) assessed the effect of immediate vs delayed coronary angiography in patients with out-of-hospital cardiac arrest (OHCA) without ST-segment elevations and found no difference in short-term survival. However, the association of these strategies with long-term outcomes and the identification of patient subgroups that might benefit from tailored approaches remain unclear.Objective: To compare immediate vs delayed or selective coronary angiography treatment strategies for patients with OHCA without ST elevation and the effect on 1-year survival, and identify subgroups that may differ in treatment effect based on patient or clinical features.Data Sources: Ovid MEDLINE, Embase, and Clarivate/Web of Science Core Collection were searched for relevant literature from inception to September 8, 2022.Study Selection: RCTs investigating immediate vs delayed or selective coronary angiography after OHCA without ST-segment elevations and a minimum follow-up period of 1 year. Data were combined using the 1-stage individual participant data meta-analysis (IPDMA) approach.Data Extraction and Synthesis: Individual patient data were obtained from RCTs that met the eligibility criteria: COACT (Coronary Angiography After Cardiac Arrest) and TOMAHAWK (Immediate Unselected Coronary Angiography vs Delayed Triage in Survivors of Out-of-Hospital Cardiac Arrest Without ST-Segment Elevation).Main Outcomes and Measures: The primary end point was 1-year survival. Secondary outcomes included the identification of variations in treatment effect using subgroup analysis (based on age, sex, arrest rhythm, witnessed arrest, time to basic life support, time to return of spontaneous circulation, and history of coronary artery disease, diabetes, and hypertension) and clinical outcomes (eg, myocardial infarction and heart failure) at 1 year.Results: For the IPDMA, data were derived from 2 RCTs comprising a total of 1031 patients. In the immediate angiography group, 259 of 522 (49.6%) survived until 1 year vs 272 of 509 (53.4%) in the delayed or selective angiography group (stratified by randomized trial; hazard ratio, 1.15 [95% CI, 0.96-1.37). No treatment-by-subgroup interactions were identified that suggested heterogeneity between the 2 groups (P values for interaction ranged from P = .26 to P = .91 across subgroups).Conclusions and Relevance: In this IPDMA of 2 RCTs, there was no benefit of immediate coronary angiography compared with a delayed or selective strategy during 1-year follow-up in successfully resuscitated patients with OHCA without ST-segment elevations. No subgroup of patients was identified that showed a differential treatment effect.Trial Registration: PROSPERO Identifier: CRD42022346559; COACT Netherlands Trial Register Identifier: NTR4973; TOMAHAWK ClinicalTrials.gov Identifier: NCT02750462

ST-depression and T-wave inversion are frequently present on the post-resuscitation electrocardiogram (ECG). However, the prognostic value of ischaemic ECG patterns is unknown. In this post-hoc subgroup analysis of the Coronary Angiography after Cardiac arrest (COACT) trial, the first in-hospital post-resuscitation ECG in out-of-hospital cardiac arrest patients with a shockable rhythm was analysed for ischaemic ECG patterns. Ischaemia was defined as ST-depression of ≥0.1 mV, T-wave inversion in ≥2 contiguous leads, or both. The primary endpoint was 90-day survival. Secondary endpoints were rate of acute unstable lesions, levels of serum troponin-T, and left ventricular function. Of the 510 out-of-hospital cardiac arrest patients, 340 (66.7%) patients had ischaemic ECG patterns. Patients with ischaemic ECG patterns had a worse 90-day survival compared with those without [hazard ratio 1.51; 95% confidence interval (CI) 1.08–2.12; P = 0.02]. A higher sum of ST-depression was associated with lower survival (log-rank = 0.01). The rate of acute unstable lesions (14.5 vs. 15.8%; odds ratio 0.90; 95% CI 0.51–1.59) did not differ between the groups. In patients with ischaemic ECG patterns, maximum levels of serum troponin-T (μg/L) were higher [0.595 (interquartile range 0.243–1.430) vs. 0.359 (0.159–0.845); ratio of geometric means 1.58; 1.13–2.20] and left ventricular function (%) was worse (44.7 ± 12.5 vs. 49.9 ± 13.3; mean difference −5.13; 95% CI −8.84 to −1.42). Adjusted for age and time to return of spontaneous circulation, ischaemic ECG patterns were no longer associated with survival. Post-arrest ischaemic ECG patterns were associated with worse 90-day survival. A higher sum of ST-depression was associated with lower survival. Adjusted for age and time to return of spontaneous circulation, ischaemic ECG patterns were no longer associated with survival.