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.

Prognostic Implications of Door-to-Balloon Time and Onset-to-Door Time on Mortality in Patients With ST -Segment-Elevation Myocardial Infarction Treated With Primary Percutaneous Coronary Intervention

Background In patients with ST-segment-elevation myocardial infarction, timely reperfusion therapy with door-to-balloon (D2B) time <90 minutes is recommended by the current guidelines. However, whether further shortening of symptom onset-to-door (O2D) time or D2B time would enhance survival of patients with ST-segment-elevation myocardial infarction remains unclear. Therefore, the current study aimed to evaluate the prognostic impact of O2D or D2B time in patients with ST-segment-elevation myocardial infarction who underwent primary percutaneous coronary intervention. Methods and Results We analyzed 5243 patients with ST-segment-elevation myocardial infarction were treated at 20 tertiary hospitals capable of primary percutaneous coronary intervention in Korea. The association between O2D or D2B time with all-cause mortality at 1 year was evaluated. The median O2D time was 2.0 hours, and the median D2B time was 59 minutes. A total of 92.2% of the total population showed D2B time ≤90 minutes. In univariable analysis, 1-hour delay of D2B time was associated with a 55% increased 1-year mortality, whereas 1-hour delay of O2D time was associated with a 4% increased 1-year mortality. In multivariable analysis, D2B time showed an independent association with mortality (adjusted hazard ratio, 1.90; 95% CI , 1.51-2.39; P<0.001). Reducing D2B time within 45 minutes showed further decreased risk of mortality compared with D2B time >90 minutes (adjusted hazard ratio, 0.30; 95% CI , 0.19-0.42; P<0.001). Every reduction of D2B time by 30 minutes showed continuous reduction of 1-year mortality (90 to 60 minutes: absolute risk reduction, 2.4%; number needed to treat, 41.9; 60 to 30 minutes: absolute risk reduction, 2.0%; number needed to treat, 49.2). Conclusions Shortening D2B time was significantly associated with survival benefit, and the survival benefit of shortening D2B time was consistently observed, even <60 to 90 minutes.

Yentl's Bikini: Sex Differences in STEMI

See Article Stehli et al

Racial Difference in Symptom Onset to Door Time in ST Elevation Myocardial Infarction

BACKGROUND

There are poorer outcomes following ST elevation myocardial infarction in blacks compared to white patients despite comparable door-to-reperfusion time. We hypothesized that delays to hospital presentation may be contributory.

METHODS AND RESULTS

We conducted a retrospective analysis of the 1144 patients admitted for STEMI in our institution from 2008 to 2013. The door-to-balloon time (D2BT) and symptom-onset-to-door time (SODT) were compared by race. Bivariate analysis was done comparing the median D2BT and SODT. Stratified analyses were done to evaluate the effect of race on D2BT and SODT, accounting for insurance status, age, sex and comorbidities. The mean age was 59±13 years; 56% of this population was black and 41% was white. Males accounted for 66% of this population. The median D2BT was 60 minutes (interquartile range [IQR] 42-82), and median SODT was 120 minutes (IQR 60-720). There was no significant difference in D2BT by race (P=0.86). Black patients presented to the emergency room (ER) later than whites (SODT=180 [IQR 60-1400] vs 120 [IQR 60-560] minutes, P<0.01) and were more likely to be uninsured (P<0.01). After controlling for comorbidities, insurance, and socioeconomic status, blacks were 60% more likely to present late after a STEMI (OR 1.6, P<0.01). A subset analysis excluding transferred patients showed similar results.

CONCLUSIONS

Black patients present later to the ER after STEMI with no difference in D2BT compared to whites. This difference in time to presentation may be one of the factors accounting for poor outcomes in this population.