Mode of hospital presentation in patients with non-ST-elevation myocardial infarction: implications for strategic management

Retrospective review of non-ST segment elevation acute coronary syndrome presenting to the emergency department of a major tertiary center in Saudi Arabia

BACKGROUND

Acute coronary syndrome (ACS) comprises a spectrum of diseases ranging from unstable angina (UA), non-ST elevation myocardial infarction (non-STEMI) and ST elevation myocardial infarction (STEMI). Treatment of ACS without STEMI (NSTEMI-ACS) can vary, depending on the severity of presentation and multiple other factors.

OBJECTIVE

Analyze the NSTEMI-ACS patients in our institution.

DESIGN

Retrospective observational.

SETTING

A tertiary care institution with accredited chest pain center.

PATIENTS AND METHODS

The travel time from ED booking to the final disposition for patients presenting with chest pain was retrieved over a period of 6 months. The duration of each phase of management was measured with a view to identify the factors that influence their management and time from the ED to their final destination. The data was analyzed using descriptive statistics.

MAIN OUTCOME MEASURES

Travel time from ED to final destination.

SAMPLE SIZE

300 patients.

RESULTS

The majority of patients were males (64%) between 61 and 80 years of age (45%). The median disposition time (from ED booking to admission order by the cardiology team) was 5 hours and 19 minutes. Cardiology admissions took 10 hours and 20 minutes from ED booking to the inpatient bed. UA was diagnosed in 153 (51%) patients and non-STEMI in 52 (17%). Coronary catheterization was required in 79 (26%) patients, 24 (8%) had coronary artery bypass grafting (CABG) and 8 (3%) had both catheterization and CABG.

CONCLUSION

The time from ED booking to final destination for NSTEMI-ACS patients is delayed due to multiple factors, which caused significant delays in overall management. Additional interventional steps can help improve the travel times, diagnosis, management and disposition of these patients.

LIMITATIONS

Single center study done in a tertiary care center so the results from this study may not be extrapolated to other centers.

Invasive and antiplatelet treatment of patients with non-ST-segment elevation myocardial infarction: Understanding and addressing the global risk-treatment paradox

Clinical guidelines for the treatment of patients with non-ST-segment elevation myocardial infarction (NSTEMI) recommend an invasive strategy with cardiac catheterization, revascularization when clinically appropriate, and initiation of dual antiplatelet therapy regardless of whether the patient receives revascularization. However, although patients with NSTEMI have a higher long-term mortality risk than patients with ST-segment elevation myocardial infarction (STEMI), they are often treated less aggressively; with those who have the highest ischemic risk often receiving the least aggressive treatment (the "treatment-risk paradox"). Here, using evidence gathered from across the world, we examine some reasons behind the suboptimal treatment of patients with NSTEMI, and recommend approaches to address this issue in order to improve the standard of healthcare for this group of patients. The challenges for the treatment of patients with NSTEMI can be categorized into four "P" factors that contribute to poor clinical outcomes: patient characteristics being heterogeneous; physicians underestimating the high ischemic risk compared with bleeding risk; procedure availability; and policy within the healthcare system. To address these challenges, potential approaches include: developing guidelines and protocols that incorporate rigorous definitions of NSTEMI; risk assessment and integrated quality assessment measures; providing education to physicians on the management of long-term cardiovascular risk in patients with NSTEMI; and making stents and antiplatelet therapies more accessible to patients.

Utilization and Costs of Noninvasive Cardiac Tests After Acute Coronary Syndromes: Insights From the Alberta COAPT Study

Background

Although appropriate noninvasive cardiac tests (NICTs) after an acute coronary syndrome (ACS) provide useful prognostic information, inappropriate use leads to inefficient expenditure of existing healthcare resources. By using the Alberta Contemporary Acute Coronary Syndrome Patient Invasive Treatment Strategies (COAPT) Registry, we evaluated the use and costs of NICTs among patients discharged within 1 year after ACS.

Methods

All patients discharged from the hospital with a primary diagnosis of ACS in Alberta between 2004/2005 and 2015/2016 were included. Frequency of NICTs (stress tests [± imaging] and nonstress imaging tests) was determined from linked provincial databases. Costs were obtained from the Alberta Health Care Insurance Plan Medical Procedure List.

Results

Of 55,516 patients with ACS, 30,760 had at least 1 NICT (55.4%), with 13,505 (24.3%) having > 1 NICT performed within 1 year. Temporal trends of NICT increased over time (stress tests: P trend < 0.001; nonstress imaging tests: P trend < 0.001). NICT most commonly occurred within the first 4 months after hospital discharge (stress tests at 2 months; nonstress imaging tests at 3-4 months). In 2015/2016, the total estimated costs of NICT were $1.35M, a 22.4% increase from 2004/2005 (1.10M) (P < 0.001), whereas a decrease in incidence of ACS over the same time period was noted (P = 0.008).

Conclusions

Rates of NICT 1 year after ACS are high and increasing over time. Estimated costs of NICT appear to be escalating out of proportion to the ACS growth. Further investigation is warranted because it is speculative whether the increase in NICT and costs results in clinical benefit after ACS.

Ambulance use, distance and outcomes in patients with suspected cardiovascular disease: a registry-based geographic information system study

BACKGROUND

Despite guideline recommendations, the majority of patients with symptoms suggestive of acute coronary syndrome do not use emergency medical services to reach the emergency department (ED). The aim of this study was to investigate the factors associated with EMS utilisation and subsequent patient outcomes.

METHODS

Using administrative data, all patients who presented to an ED in the metropolitan areas of Edmonton and Calgary in the years of 2007-2013 with main ED diagnosis of acute coronary syndrome, stable angina or chest pain were included. The travel distance was estimated using the geographic information system method to approximate the distance between the ED and patient home. The clinical endpoints were the 7-day and 30-day all-cause events (death, re-hospitalisation and repeat ED visit).

RESULTS

Of 50,881 patients, 30.5% presented by emergency medical services. Patients with older age, female sex, ED diagnosis of acute coronary syndrome, more comorbidities and lower household income were more likely to use emergency medical services to reach the hospital. Longer travel distance was associated with higher emergency medical services use (odds ratio 1.09, 95% confidence interval 1.09-1.10), but it was not a predictor of clinical events. After adjustment for covariates and inverse propensity score weighting, emergency medical services use was associated with a higher risk of 7-day and 30-day clinical events.

CONCLUSION

Several demographic and clinical features were associated with higher emergency medical services use including geographical variation. Although longer travel distance was shown to be linked to higher emergency medical services use, it was not an independent predictor of patient outcome. This has implications for the design of emergency medical services systems, triage and early diagnosis and treatment options.

Myocardial infarction: sex differences in symptoms reported to emergency dispatch

BACKGROUND

Emergency management of myocardial infarction (MI) is time-critical, because improved patient outcomes are associated with reduced time from symptom onset to definitive care. Previous studies have identified that women are less likely to present with chest pain.

OBJECTIVE

We sought to measure the effect of sex on symptoms reported to the ambulance dispatch and ambulance times for MI patients.

METHODS

The Western Australia Emergency Department Information System (EDIS) was used to identify patients with emergency department (ED) diagnoses of MI (ST-segment elevation MI and non-ST-segment elevation MI) who arrived by ambulance between January 1, 2008, and October 31, 2009. Their emergency telephone calls to the ambulance service were transcribed to identify presenting symptoms. Ambulance data were used to examine ambulance times. Sex differences were analyzed using descriptive and age-adjusted regression analysis.

RESULTS

Of 3,329 MI patients who presented to Perth EDs, 2,100 (63.1%) arrived by ambulance. After predefined exclusions, 1,681 emergency calls were analyzed. The women (n = 621; 36.9%) were older than the men (p < 0.001) and, even after age adjustment, were less likely to report chest pain (odds ratio [OR] = 0.70; 95% confidence interval [CI] 0.57, 0.88). After age adjustment, ambulance times did not differ between the male and female patients with chest pain. The women with chest pain were less likely than the men with chest pain to be allocated a "priority 1" (lights and sirens) ambulance response (men 98.3% vs. women 95.5%; OR = 0.39; 95% CI 0.18, 0.87).

CONCLUSION

Ambulance dispatch officers (and paramedics) need to be aware of potential sex differences in MI presentation in order to ensure appropriate ambulance response.