Unstable Angina Pectoris With Myocardial Injury Versus Myocardial Infarction in the Era of High-Sensitivity Cardiac...

Area of Science:

• Cardiology
• Clinical Medicine
• Biomarkers

Background:

• Unstable angina pectoris (UAP) and non-ST-segment myocardial infarction (NSTEMI) are critical cardiovascular conditions.
• The prognostic implications of myocardial injury in UAP versus NSTEMI with varying peak high-sensitivity cardiac troponin T (hs-cTnT) levels remain unclear.

Purpose of the Study:

• To compare the long-term prognosis of patients diagnosed with UAP and myocardial injury against patients with NSTEMI.
• To analyze outcomes based on different peak hs-cTnT concentrations in NSTEMI patients.

Main Methods:

• Retrospective cohort study utilizing data from 7 Swedish emergency departments (2009-2016).
• Inclusion criteria: hospitalized patients with hs-cTnT >14 ng/L and diagnoses of UAP or NSTEMI, with at least two hs-cTnT measurements.
• Outcomes assessed: all-cause mortality, cardiovascular events, recurrent myocardial infarction, and heart failure hospitalization, analyzed using hazard ratios (HRs).

Main Results:

• A total of 11,944 patients were included (1,253 with UAP).
• No significant difference in long-term cardiovascular mortality between UAP patients and NSTEMI patients with peak hs-cTnT of 15-49 ng/L (HR 1.15; 95% CI, 0.85-1.56).
• NSTEMI patients had a higher risk of recurrent myocardial infarction (HR 1.61; 95% CI, 1.29-2.00) and a lower risk of heart failure hospitalization (HR 0.80; 95% CI, 0.64-0.99) compared to UAP patients.

Conclusions:

• Patients with UAP and myocardial injury exhibit comparable long-term mortality rates to NSTEMI patients with moderately elevated hs-cTnT.
• UAP patients demonstrate a reduced risk of recurrent myocardial infarction but a slightly increased risk of heart failure hospitalization post-discharge.
• These findings highlight distinct prognostic trajectories for UAP and NSTEMI, informing clinical management strategies.