Contemporary management of ST-segment elevation myocardial infarction

Trends in ST-elevation myocardial infarction

AIMS

Despite recent progress in coronary artery disease treatment, ST-segment elevation myocardial infarction (STEMI) remains a very high-risk medical condition. Whether recent patients' outcomes, following implementation of the 2012 European Society of Cardiology (ESC) STEMI guidelines have improved, is yet unclear.

METHODS AND RESULTS

The study was based on a prospective detailed registry of 2004 consecutive patients with STEMI treated with primary percutaneous coronary intervention (pPCI). We compared trends during two different time periods (2006-2012 vs. 2012-2018). Endpoints included mortality and major adverse cardiac events (MACE: death, repeat myocardial infarction, target vessel revascularization and coronary artery bypass surgery) at 1 month, 1 and 2 years. Rates of transradial interventions have risen significantly (67.3 vs. 42.0%; P < 0.01), as have rates of prasugrel administration (69.8 vs. 4.5%; P < 0.01) and use of drug eluting stents (75.5 vs. 56.5%; P < 0.01). Both at 1 and at 2 years, MACE was significantly lower in the later period (11.6 vs. 20.9%; P < 0.01 and 18.9 vs. 25.4%; P < 0.01 respectively), whereas mortality was only significantly lower after 1 year (5.8 vs. 8.6%; P = 0.02). Cox regression identified the later period (2012-2018) to independently and favorably impact MACE (hazard ratio, -0.69; 95% CI, 0.56-0.85; P < 0.01) but not mortality (hazard ratio, -0.76; 95% CI, 0.54-1.05; P = 0.09).

CONCLUSION

Among patients treated with pPCI for STEMI, adoption of the contemporary evidence-based treatments is associated with better MACE derived outcomes, following the inception of the 2012 ESC guidelines. Nonetheless, the long-term mortality was marginally (but not significantly) lower, which indicates an unmet need for further improvement.

ST-segment elevation myocardial infarction with non-chest pain presentation at the Emergency Department: Insights from the Singapore Myocardial Infarction Registry

ST-segment elevation myocardial infarction (STEMI) often presents acutely at the Emergency Department (ED). Although chest pain is a classical symptom, a significant proportion of patients do not present with chest pain. The impact of a non-chest pain (NCP) presentation on ED processes-of-care and outcomes is not fully understood. We utilised a national registry to characterise predictors, processes-of-care, and outcomes of NCP STEMI presentations. Retrospective data for all STEMI cases occurring between 2010 and 2012 were analysed from the Singapore Myocardial Infarction Registry. Cases of inpatient onset, inter-facility transfers, and out-of-hospital cardiac arrests were excluded. Univariable analysis of demographic, clinical, processes-of-care, and outcome variables was conducted. Multivariable logistic regression ascertained independent predictors of a NCP presentation and 28-day mortality. Of 4667 STEMI cases, 12.9% presented without chest pain. Patients with NCP presentation were older (median, years = 74 vs. 58; p < 0.001), more likely to be female (39.1% vs. 15.7%; p < 0.001), of the Chinese race (72.5% vs. 62.7%; p < 0.001), and with diabetes (48.6% vs. 36.7%; p < 0.001). These patients were more likely to present with syncope (6.0% vs. 1.9%; p < 0.001) or epigastric pain (10.6% vs. 4.9%; p < 0.001). Patients with NCP presentation were less likely to receive percutaneous coronary intervention (27.0% vs. 75.6%; p < 0.001), had longer door-to-balloon time (median, minutes = 83 vs. 63; p < 0.001), and experienced greater mortality at 28 days (31.2% vs. 4.5%; p < 0.001). On multivariable logistic regression, independent predictors of a NCP presentation included age (adjusted odds ratio [aOR] = 1.05, 95% confidence interval [CI] 1.04-1.07), diabetes (aOR = 1.76, 95% CI 1.40-2.19), BMI (aOR = 0.93, 95% CI 0.91-0.96), and dyslipidemia (aOR = 0.73, 95% CI 0.58-0.91). Absence of chest pain was an independent predictor for 28-day mortality (aOR = 3.46, 95% CI 2.64-4.52). Patients who presented with a NCP STEMI had a distinct clinical profile and experienced poorer outcomes. Routine triage ECG could be considered for patients with high-risk factors and non-classical symptoms.

The Effects of Acute Atmospheric Pressure Changes on the Occurrence of ST-Elevation Myocardial Infarction: A Case-Crossover Study

BACKGROUND

Few studies have explored the influence of short-term exposure to atmospheric pressure changes on the abrupt onset of ST-elevation myocardial infarction (STEMI). We sought to evaluate the association between acute atmospheric pressure changes and the occurrence of STEMI.

METHODS

We studied STEMI patients from the Alberta Provincial Project for Outcomes Assessment in Coronary Heart Disease (APPROACH) from March 1, 2002 to December 31, 2016 in a case-crossover study design. Each case was matched with control intervals according to the same day of week, month, and year. All STEMI patients were linked with the nearest weather station within a 40-km radius according to residential postal code. The effect of exposure to air pressure changes, rate of air pressure changes, acute air pressure increase, and acute air pressure decrease 1 day to 7 days earlier on the onset of STEMI were analyzed with conditional logistic regression. All models were adjusted with daily average temperature, relative humidity, and average levels of 5 air pollutants.

RESULTS

In 11,379 STEMI patients, positive associations with the onset of STEMI were only found at 7 days after exposure to acute air pressure decrease (odds ratio, 1.12; 95% confidence interval, 1.03-1.21), which was consistent in sensitivity and subgroup analyses. All the other models showed no evidence of statistically significant associations.

CONCLUSIONS

Acute air pressure decrease is associated with higher odds of a STEMI event 7 days after exposure. Weather advisories might be issued when atmospheric pressure decrease occurs.