Prognostic evaluation of a group of patients with chest pain and cardiac troponin flat curve

Acute myocardial injury is defined by cardiac troponin (cTn) levels exceeding the 99th percentile upper reference limit, with dynamic rise/fall pattern (Δ), often suggesting acute coronary syndrome (ACS). However, some patients present with chest pain and elevated cTn but with a Δ<20% (flat curve). Aim of this study is to analyze the prognosis of these patients based on their management: admission to Cardiology, other departments, or discharge from the Emergency Department.

We prospectively analyzed data of patients with suspected ACS and a cTn-flat curve (Δ<20% in two high-sensitivity cTn-T determinations at 0/3 hours) from May 2023 to October 2024. A six-month follow-up was completed in 245 patients, with a median follow-up of 186 days. Prognosis was based on major cardiovascular events (MACE: mortality, infarction, revascularization, stroke, or vascular surgery) and non-cardiovascular events.

In this group of patients mean age was 75.6±11.9 years, 61.4% males. Sixty-five patients were admitted to Cardiology, 50 to other departments, and 130 were discharged directly from the emergency department. Fifty-two patients (21%) were diagnosed with ACS. Patients admitted to other departments had more MACE and more non-cardiovascular events. Mortality in all groups was mostly due to non-cardiac causes. These results are shown in Table 1. Cardiac mortality was mainly due to heart failure in all three groups: congestive heart failure was responsible for 87% of cardiovascular deaths. Differences in survival were also compared by grouping patients into two different groups: admission (Cardiology and other departments) vs. non-admission. The Kaplan-Meier curves are shown in this case in Figure 1. No significant differences were found between these two groups regarding the time to first MACE appearance.