Comparison of Outcome of Patients With ST-Segment Elevation Myocardial Infarction and Complete Versus Incomplete ST-Resolution Before Primary Percutaneous Coronary Intervention

A comprehensive guide on the optimal timing of PCI in the setting of acute coronary syndrome: An updated meta-analysis

BACKGROUND

Invasive revascularization is recommended for cohorts of patients with ST-elevation myocardial infarction (STEMI) and non-ST-elevation acute coronary syndrome (NSTE-ACS). However, the optimal timing of invasive revascularization is still controversial and no defined consensus is established. We aim to give a comprehensive appraisal on the optimal timing of invasive strategy in the heterogenous population of ACS.

METHODS

Relevant studies were assessed through PubMed, Scopus, Web of science, and Cochrane Library from inception until April 2023. Major adverse cardiovascular events (MACE) and all-cause mortality were our primary outcomes of interest, other secondary outcomes were cardiac death, TVR, MI, repeat revascularization, recurrent ischemia, and major bleeding. The data was pooled as odds ratio (OR) with its 95% confidence interval (CI) in a random effect model using STATA 17 MP.

RESULTS

A total of 26 studies comprising 21,443 patients were included in the analysis. Early intervention was favor to decrease all-cause mortality (OR = 0.79, 95% CI: 0.64 to 0.98, p = 0.03), when compared to delayed intervention. Subgroup analysis showed that early intervention was significantly associated with all-cause mortality reduction in only NSTE-ACS (OR = 0.83, 95% CI [0.7 to 0.99], p = 0.04). However, there was no significant difference between early and delayed intervention in terms of MACE, cardiac death, TVR, MI, repeat revascularization, recurrent ischemia, and major bleeding.

CONCLUSION

An early intervention was associated with lower mortality rates compared to delayed intervention in NSTE-ACS with no significant difference in other clinical outcomes. PROSPERO registration: CRD42023415574.

Direct Stenting versus Conventional Stenting in Patients with ST-Segment Elevation Myocardial Infarction-A COMPARE CRUSH Sub-Study

BACKGROUND

Direct stenting (DS) compared with conventional stenting (CS) after balloon predilatation may reduce distal embolization during percutaneous coronary intervention (PCI), thereby improving tissue reperfusion. In contrast, DS may increase the risk of stent underexpansion and target lesion failure.

METHODS

In this sub-study of the randomized COMPARE CRUSH trial (NCT03296540), we reviewed the efficacy of DS versus CS in a cohort of contemporary, pretreated ST-segment elevation myocardial infarction (STEMI) patients undergoing primary PCI. We compared DS versus CS, assessing (1) stent diameter in the culprit lesion, (2) thrombolysis in myocardial infarction (TIMI) flow in the infarct-related artery post-PCI and complete ST-segment resolution (STR) one-hour post-PCI, and (3) target lesion failure at one year. For proportional variables, propensity score weighting was applied to account for potential treatment selection bias.

RESULTS

This prespecified sub-study included 446 patients, of whom 189 (42%) were treated with DS. Stent diameters were comparable between groups (3.2 ± 0.5 vs. 3.2 ± 0.5 mm, p = 0.17). Post-PCI TIMI 3 flow and complete STR post-PCI rates were similar between groups (DS 93% vs. CS 90%, adjusted OR 1.16 [95% CI, 0.56-2.39], p = 0.69, and DS 72% vs. CS 58%, adjusted OR 1.29 [95% CI 0.77-2.16], p = 0.34, respectively). Moreover, target lesion failure rates at one year were comparable (DS 2% vs. 1%, adjusted OR 2.93 [95% CI 0.52-16.49], p = 0.22).

CONCLUSION

In this contemporary pretreated STEMI cohort, we found no difference in early myocardial reperfusion outcomes between DS and CS. Moreover, DS seemed comparable to CS in terms of stent diameter and one-year vessel patency.

Left ventricular function, strain, and infarct characteristics in patients with transient ST-segment elevation myocardial infarction compared to ST-segment and non-ST-segment elevation myocardial infarctions

AIMS

This study aims to explore cardiovascular magnetic resonance (CMR)-derived left ventricular (LV) function, strain, and infarct size characteristics in patients with transient ST-segment elevation myocardial infarction (TSTEMI) compared to patients with ST-segment and non-ST-segment elevation myocardial infarctions (STEMI and NSTEMI, respectively).

METHODS AND RESULTS

In total, 407 patients were enrolled in this multicentre observational prospective cohort study. All patients underwent CMR examination 2-8 days after the index event. CMR cine imaging was performed for functional assessment and late gadolinium enhancement to determine infarct size and identify microvascular obstruction (MVO). TSTEMI patients demonstrated the highest LV ejection fraction and the most preserved global LV strain (longitudinal, circumferential, and radial) across the three groups (overall P ≤ 0.001). The CMR-defined infarction was less frequently observed in TSTEMI than in STEMI patients [77 (65%) vs. 124 (98%), P < 0.001] but was comparable with NSTEMI patients [77 (65%) vs. 66 (70%), P = 0.44]. A remarkably smaller infarct size was seen in TSTEMI compared to STEMI patients [1.4 g (0.0-3.9) vs. 13.5 g (5.3-26.8), P < 0.001], whereas infarct size was not significantly different from that in NSTEMI patients [1.4 g (0.0-3.9) vs. 2.1 g (0.0-8.6), P = 0.06]. Whilst the presence of MVO was less frequent in TSTEMI compared to STEMI patients [5 (4%) vs. 53 (31%), P < 0.001], no significant difference was seen compared to NSTEMI patients [5 (4%) vs. 5 (5%), P = 0.72].

CONCLUSION

TSTEMI yielded favourable cardiac LV function, strain, and infarct-related scar mass compared to STEMI and NSTEMI. LV function and infarct characteristics of TSTEMI tend to be more similar to NSTEMI than STEMI.

Transient ST-elevation myocardial infarction versus persistent ST-elevation myocardial infarction. An appraisal of patient characteristics and functional outcome

BACKGROUND

Up to 24% of patients presenting with ST-elevation myocardial infarction (STEMI) show resolution of ST-elevation and symptoms before revascularization. The mechanisms of spontaneous reperfusion are unclear. Given the more favorable outcome of transient STEMI, it is important to obtain further insights in differential aspects.

METHODS

We compared 251 patients who presented with transient STEMI (n = 141) or persistent STEMI (n = 110). Clinical angiographic and laboratory data were collected at admission and in subset of patients additional index hemostatic data and at steady-state follow-up. Cardiac magnetic resonance imaging (CMR) was performed at 2-8 days to assess myocardial injury.

RESULTS

Transient STEMI patients had more cardiovascular risk factors than STEMI patients, including more arterial disease and higher cholesterol values. Transient STEMI patients showed angiographically more often no intracoronary thrombus (41.1% vs. 2.7%, P < 0.001) and less often a high thrombus burden (9.2% vs. 40.0%, P < 0.001). CMR revealed microvascular obstruction less frequently (4.2% vs. 34.6%, P < 0.001) and smaller infarct size [1.4%; interquartile range (IQR), 0.0-3.7% vs. 8.8%; IQR, 3.9-17.1% of the left ventricle, P < 0.001] with a better preserved left ventricular ejection fraction (57.8 ± 6.7% vs. 52.5 ± 7.6%, P < 0.001). At steady state, fibrinolysis was higher in transient STEMI, as demonstrated with a reduced clot lysis time (89 ± 20% vs. 99 ± 25%, P = 0.03).

CONCLUSIONS

Transient STEMI is a syndrome with less angiographic thrombus burden and spontaneous infarct artery reperfusion, resulting in less myocardial injury than STEMI. The presence of a more effective fibrinolysis in transient STEMI patients may explain these differences and might provide clues for future treatment of STEMI.

NT-proBNP level before primary PCI and risk of poor myocardial reperfusion: Insight from the On-TIME II trial

BACKGROUND

N-terminal fragment of the brain natriuretic peptide prohormone (NT-proBNP), a marker for neurohumoral activation, has been associated with adverse outcome in patients with myocardial infarction. NT-proBNP levels may reflect extensive ischemia and microvascular damage, therefore we investigated the potential association between baseline NT-proBNP level and ST-resolution (STR), a marker of myocardial reperfusion, after primary percutaneous coronary intervention (pPCI).

METHODS

we performed a post-hoc analysis of the On-TIME II trial (which randomized ST-elevation myocardial infarction (STEMI) patients to pre-hospital tirofiban administration vs placebo). Patients with measured NT-proBNP before angiography were included. Multivariate logistic-regression analyses was performed to investigate the association between baseline NTproBNP level and STR one hour after pPCI.

RESULTS

Out of 984 STEMI patients, 918 (93.3%) had NT-proBNP values at baseline. Patients with STR <70% had higher NT-proBNP values compared to patients with complete STR (>70%) [Mean ±SD 375.2 ±1021.7 vs 1007.4 ±2842.3, Median (IQR) 111.7 (58.4-280.0) vs 168.0 (62.3-601.3), P <.001]. At multivariate logistic regression analysis, independent predictors associated with higher risk of poor myocardial reperfusion (STR <70%) were: NT-proBNP (OR 1.17, 95%CI 1.04-1.31, P = .009), diabetes mellitus (OR 1.87, 95%CI 1.14-3.07, P = .013), anterior infarct location (OR 2.74, 95% CI 2.00-3.77, P <.001), time to intervention (OR 1.06, 95%CI 1.01-1.11, P = .021), randomisation to placebo (OR 1.45, 95%CI 1.05-1.99, P = .022).

CONCLUSIONS

In STEMI patients, higher baseline NT-proBNP level was independently associate with higher risk of poor myocardial reperfusion, supporting the potential use of NT-proBNP as an early marker for risk stratification of myocardial reperfusion after pPCI in STEMI patients.

Primary percutaneous coronary intervention is appropriate in transient ST-elevation myocardial infarction

INTRODUCTION

Reperfusion therapy by primary percutaneous coronary intervention (PPCI) is generally indicated in patients suffering from acute myocardial infarction (MI) with ST-segment elevation (STEMI). Prior to hospital admission, full ST-segment resolution (fSTR) may occur. Optimal management of such patients with transient STEMI (TSTEMI) is potentially challenging. Our aim was to evaluate the hypothesis that in TSTEMI patients, patency of infarct related artery (IRA) is achieved before PPCI, and to compare the outcome of TSTEMI and STEMI patients during a prolonged follow-up.

MATERIAL AND METHODS

Three hundred consecutive adult STEMI patients were referred to catheterization laboratory. In all patients, standard 12 lead ECGs were obtained both at the time of the first medical contact, and on catheterization laboratory admission.

RESULTS

TSTEMI occurred in 20 patients (6.7%). Despite fSTR (isoelectric ST segment), occluded IRA was found in 5 of these patients (25%). Pre-PPCI TIMI flow grade 2 was found in 6 TSTEMI patients (30%). Troponin T value at 24 h after symptom onset was lower in the TSTEMI group (1.8±2.5 mg/L vs. 3.6±3.5 mg/L, P=0.008). These patients also had a lower value of brain natriuretic peptide (156.3±119.5 ng/L vs. 438.5±429.0 ng/L, P<0.001) and higher left ventricular ejection fraction (59.9±6.3% vs. 51.6±10.2%, P<0.001). All patients were followed for a median of 5.6 years during which the overall survival did not differ between the TSTEMI and STEMI groups.

CONCLUSION

Primary PCI is strongly recommended in TSTEMI patients because of a relatively high incidence of occluded infarct related arteries. The rate of patients with TSTEMI is relatively low.