Objectives: The aim of this analysis was to compare troponin-positive patients presenting to a chest pain unit (CPU) and undergoing coronary angiography with or without subsequent revascularization. Leading diagnosis, disease distribution, and short-term outcomes were evaluated.
Background: Chest pain units are increasingly implemented to promptly clarify acute chest pain of uncertain origin, including patients with suspected acute coronary syndrome (ACS).
Methods: A total of 11,753 patients were prospectively enrolled into the German CPU-Registry of the German Cardiac Society between December 2008 and April 2011. All patients with elevated troponin undergoing a coronary angiography were selected. Three months after discharge a follow-up was performed.
Results: A total of 2,218 patients were included. 1,613 troponin-positive patients (72.7 %) underwent a coronary angiography with subsequent PCI or CABG and had an ACS in 96.0 %. In contrast, 605 patients (27.3 %) underwent a coronary angiography without revascularization and had an ACS in 79.8 %. The most frequent non-coronary diagnoses in non-revascularized patients were acute arrhythmias (13.4 %), pericarditis/myocarditis (4.5 %), decompensated congestive heart failure (3.7 %), Takotsubo cardiomyopathy (2.7 %), hypertensive crisis (2.4 %), and pulmonary embolism (0.3 %). During the 3-month followup, patients without revascularization had a higher mortality (12.1 vs. 4.5 %, p<0.0001) representing the major contributor to the higher rate of MACCE (15.1 vs. 8.1 %, p<0.001). These data were confirmed in a subgroup analysis of ACS patients with or without revascularization.
Conclusions: Patients presenting to a CPU with elevated troponin levels mostly suffer from ACS and in a smaller proportion a variety of different diseases are responsible. The short-term outcome in troponin-positive patients with or without an ACS not undergoing a revascularization was worse, indicating that these patients were more seriously ill than patients with revascularization of the culprit lesion. Therefore, an adequate diagnostic evaluation and improved treatment strategies are warranted.