Published online Dec 26, 2021. doi: 10.4330/wjc.v13.i12.745
Peer-review started: August 26, 2021
First decision: October 17, 2021
Revised: October 23, 2021
Accepted: December 3, 2021
Article in press: December 3, 2021
Published online: December 26, 2021
In the United Kingdom rapid access chest pain clinics (RACPC) have been set up in hospital centers to address the problem of non-acute chest pain of uncertain origin. The early detection of coronary artery disease (CAD) in these patients can lead to effective treatment. In this study we looked at the value of a highly sensitive troponin I assay in the rule out of functionally relevant CAD in patients referred for further assessment and investigation in a RACPC. To our knowledge this is the first study to be carried out in a non-teaching hospital in patients who presented with several clinical co-morbidities.
While functional studies and imaging techniques are valuable in the evaluation of patients with suspected CAD, highly sensitive troponin I which detects even minute concentrations of troponin I in the serum may provide further information on cardiac injury that may be associated with CAD.
The aim was to assess the role of troponin in assisting clinical decision making in the setting of a RACPC in a non-teaching hospital. This has not been explored previously.
One hundred and seventy two patients admitted to the rapid access clinic were studied. Unlike previous studies, patients with a previous history of CAD were included in the study. Following clinical assessment the patients with suspected stable CAD were assigned to 24 h monitoring electrocardiogram, exercise tolerance test, echocardiogram, exercise or pharmacological stress echo, coronary computed tomography angiography, coronary angiogram and percutaneous coronary intervention, medical treatment for angina, or were discharged as clinical assessment suggested non-cardiac chest pain. More complex patients were designated for review by specialist cardiologists.
Receiver operating characteristic curves suggest that patients with troponin I ≤ 0.52 ng/L were less likely to present with CAD and values > 11.6 ng/L required further evaluation. In the range > 0.52-11.6 ng/L troponin I was not a standalone test. In all cases troponin was best used in conjunction with clinical assessment. In patients assigned and preselected for coronary computed tomography angiography and coronary angiogram troponin I was an indicator of the severity of CAD. Cut-off levels of troponin I were determined by the patient population cohort.
The study suggests that in unselected patients presenting with suspected stable angina to a rapid access clinic troponin I is best used in conjunction with clinical evaluation of the patient. Diagnostic cut-off levels are dependent on patient population.
What is now required is further work with different population groups.