Among patients with suspected ACS and a flat cardiac troponin curve (∆<20%), 22.6% (110/485) were ultimately diagnosed with ACS, demonstrating that a flat curve does not exclude the diagnosis.
Cohort (n=485)
Does a cardiac troponin flat curve exclude acute coronary syndrome in patients with suspected ACS?
A flat cardiac troponin curve (∆<20% at 0/3 hours) does not safely rule out acute coronary syndrome, which was still diagnosed in over 20% of such patients.
Abstract Introduction and Objectives Acute myocardial injury is defined by elevated cardiac troponin (cTn) above the 99th percentile with a dynamic change (∆20%). When associated with a compatible clinical history, this suggests acute coronary syndrome (ACS). Some patients present with chest pain and initially elevated cTn but with ∆20% (flat curve). This study analyzes their clinical characteristics. Patients and Methods We prospectively analyzed patients with suspected ACS and a cTn-flat curve (∆20% in two serial high-sensitivity cTn-T determinations at 0/3 hours) from May 2023 to January 2025. Results 485 patients were included, mean age 75.6±12.3 years, 60.8% male. Their clinical characteristics are summarized in Table 1; 139 (28.6%) patients were admitted to Cardiology, 104 (21.4%) to other departments, and 242 (49.9%) were discharged directly from the emergency department. Coronary angiography was performed in 128 of the 243 patients admitted to hospitalization, revealing significant lesions in 96 (75%). Additionally, 14 patients were diagnosed with ACS through non-invasive tests. Conclusions in this group of patients cTn-flat curve did not exclude ACS; 110 cases (22.6%) had an ACS diagnosis. These patients had more males, higher cTn-T levels, more ST-T changes, wall motion abnormalities and ischemic symptoms but less atrial fibrillation.Table 1
Garcia et al. (Sat,) conducted a cohort in Suspected acute coronary syndrome with a flat cardiac troponin curve (n=485). cTn-flat curve (∆<20%) was evaluated on ACS diagnosis. Among patients with suspected ACS and a flat cardiac troponin curve (∆<20%), 22.6% (110/485) were ultimately diagnosed with ACS, demonstrating that a flat curve does not exclude the diagnosis.