Targeting an Ischemic Time <120 Minutes in ST-Segment-Elevation Myocardial Infarction

Influence of time-to-diagnosis on time-to-percutaneous coronary intervention for emergency department ST-elevation myocardial infarction patients: Time-to-electrocardiogram matters

Objectives

Earlier electrocardiogram (ECG) acquisition for ST-elevation myocardial infarction (STEMI) is associated with earlier percutaneous coronary intervention (PCI) and better patient outcomes. However, the exact relationship between timely ECG and timely PCI is unclear.

Methods

We quantified the influence of door-to-ECG (D2E) time on ECG-to-PCI balloon (E2B) intervention in this three-year retrospective cohort study, including patients from 10 geographically diverse emergency departments (EDs) co-located with a PCI center. The study included 576 STEMI patients excluding those with a screening ECG before ED arrival or non-diagnostic initial ED ECG. We used a linear mixed-effects model to evaluate D2E's influence on E2B with piecewise linear terms for D2E times associated with time intervals designated as ED intake (0-10 min), triage (11-30 min), and main ED (>30 min). We adjusted for demographic and visit characteristics, past medical history, and included ED location as a random effect.

Results

The median E2B interval was longer (76 vs 68 min, p < 0.001) in patients with D2E >10 min than in those with timely D2E. The proportion of patients identified at the intake, triage, and main ED intervals was 65.8%, 24.9%, and 9.7%, respectively. The D2E and E2B association was statistically significant in the triage phase, where a 1-minute change in D2E was associated with a 1.24-minute change in E2B (95% confidence interval [CI]: 0.44-2.05, p = 0.003).

Conclusion

Reducing D2E is associated with a shorter E2B. Targeting D2E reduction in patients currently diagnosed during triage (11-30 min) may be the greatest opportunity to improve D2B and could enable 24.9% more ED STEMI patients to achieve timely D2E.

Variations and Associated Factors in Symptom-to-Balloon (STB) Time and Door-to-Balloon (DTB) Time Before and After the COVID-19 Lockdown: A Hospital-Based Cross-Sectional Study

INTRODUCTION

During the COVID-19 lockdown, India saw a major restriction in the movement of people. Patients with acute myocardial infarction (MI) required early interventions and follow-up of independent predictors like symptom-to-balloon (STB) time and door-to-balloon (DTB) time. This study aimed to determine changes in STB and DTB time before and after the COVID-19 lockdown and its associated risk factors.

METHODS

A hospital-based cross-sectional study of 105 patients admitted to the cardiac care units (CCU) of two tertiary care centers in a district of Southern India for six months was conducted to compare the changes in STB and DTB time before and after the COVID-19 lockdown (three months before March 2020 and three months after March 2020), and data was collected from medical records. The data collected was then entered into Microsoft Excel (Microsoft Corporation, Washington, USA), numerically coded, and analyzed using SPSS Statistics version 21 (IBM Corp. Released 2012. IBM SPSS Statistics for Windows, Version 21.0. Armonk, NY: IBM Corp.). The Chi-square and Mann-Whitney U tests assessed the association between the dependent and independent variables. The STB/DTB time (before and after the COVID-19 lockdown) was the dependent variable, while the age, gender, co-morbidities, smoking status, and date of admission of patients (before and after the COVID-19 lockdown) were taken as the independent variables. A p-value of <0.05 was considered statistically significant. The predictor variables were identified using the regression method, where all variables with a significance of <0.2 were taken.

RESULTS

The overall mean (±SD) STB time was 408.7 (±307.1) minutes, and the mean (±SD) DTB time was 161.7 (±261.6) minutes. The pre-lockdown mean STB time was 404.6 minutes, and the mean DTB time was 153 minutes, whereas the post-lockdown mean STB and DTB time were higher at 413.3 minutes and 171.6 minutes, respectively. Out of the total 105 patients, 95 (90.5%) had an STB time of ≥120 minutes, and 77 (73.3%) had an ideal DTB time of <90 minutes. There was no statistically significant variation in the STB and DTB time before and after the lockdown. Only the age group >60 years (38 (97.4%)) was found to be statistically significant with an STB time of ≥120 minutes after the lockdown (p-value=0.040), and patients referred from primary and secondary care centers (AOR (95% CI)=4.669 (1.129-19.298)) were found to be an independent factor in reducing DTB time before and after the COVID-19 lockdown.

CONCLUSION

The efficiency of the health system, irrespective of the COVID-19 lockdown, was observed; nevertheless, a delay in the overall recognition of symptoms of MI was perceived. The importance of time factors in identifying the symptoms of non-communicable diseases (NCDs), especially MI and stroke, has to be ascertained among the general population.

Contemporary Implications of ECG to Activation Time on Long-term Outcomes in Patients With ST-Segment Elevation Myocardial Infarction Treated With Primary Percutaneous Coronary Intervention

PURPOSE

The prognosis of door to balloon time (DBT) after primary percutaneous coronary intervention (PPCI) in ST-segment elevation myocardial infarction (STEMI) has been extensively studied. However, the clinical implications of the ECG to activation time (EAT), as a component of DBT, on long-term outcomes are less well established. This study evaluates the association of EAT with major adverse cardiovascular events (MACEs) in more contemporary patients undergoing PPCI and investigates factors that influence EAT.

METHODS

A total of 1082 consecutive patients with STEMI who underwent PPCI from 2013 to 2019 were classified into 3 groups according to EAT: EAT ≤30 minutes, EAT of 30 to 60 minutes, and EAT >60 minutes. We analyzed the incidence of MACEs, including all-cause death, nonfatal recurrence of MI, or nonfatal stroke during a median follow-up of 37 months.

FINDINGS

The median EAT was 58 minutes (interquartile range, 44-80 minutes), which explained 90% of the variability in DBT and had the strongest correlation with DBT (r = 0.95, P < 0.001). Achieving an EAT of ≤30 minutes resulted in a 94.1% chance of achieving a DBT ≤90 minutes. The incidence of MACEs had a concurrent increase with increased EAT (10.2% for EAT ≤30 minutes, 14.3% for EAT of 30-60 minutes, and 17.3% for EAT >60 minutes; P = 0.027) that was driven by more mortality (4.2% for EAT ≤30 minutes, 6.9% for EAT of 30-60 minutes, and 9.8% for EAT >60 minutes; P = 0.020). An EAT >30 minutes was independently associated with risk-adjusted long-term MACEs (hazard ratio = 1.99; 95% CI, 1.07-3.69; P = 0.030). Critically ill status in emergency department (P = 0.001) and time required for consent of revascularization (P < 0.001) were significantly associated with delayed EAT.

IMPLICATIONS

Achieving an EAT ≤30 minutes was key to achieving the guideline-recommended target time of DBT in contemporary practice. As a strong driver of overall DBT, EAT >30 minutes was associated with worse clinical outcome in patients with STEMI undergoing PPCI. These data suggest that efforts to minimize EAT are needed to reduce long-term MACEs in contemporary population. (Clin Ther. 2021;XX:XXX-XXX) © 2021 Elsevier HS Journals, Inc.