Practicality, safety and accuracy of computed tomography coronary angiography in the evaluation of low TIMI-risk score chest pain patients: a pilot study.

OBJECTIVES: The present pilot study aimed to assess the practicality, safety and accuracy of performing CT coronary angiography (CT-CA) in the evaluation of acute chest pain of patients with low thrombolysis in myocardial infarction (TIMI) risk scores.
METHODS: The present prospective observational study was undertaken in a university teaching hospital between November 2004 and December 2005. Participants were a convenience sample of patients admitted to hospital for investigation of chest pain with TIMI risk scores <3. Consenting patients underwent CT-CA within 48 h of presentation. Outcomes of interest were practicality (proportion of diagnostic quality scans obtained and preparation time for CT-CA), rate of serious adverse events, and accuracy at the patient level using selective coronary angiography as the reference standard.
RESULTS: Thirty-four patients were recruited. Diagnostic quality scans were obtained in 26/34 or 76% of patients (four failed CT-CA and four non-diagnostic scans). The median CT preparation time was 1.9 h (range 0.17-4.0). No serious adverse events were found. Fourteen of those 26 patients with diagnostic CT-CA subsequently had selective coronary angiography, of which nine were positive. The sensitivity and specificity of CT-CA in identifying patients with significant coronary artery disease were 9/9 (100%; 95% confidence interval 72-100%) and 4/5 (80%; 95% confidence interval 28-100%), respectively.
CONCLUSIONS: The majority of acute chest pain patients with low TIMI risk scores were successfully scanned with a 16-slice CT to produce CT-CA studies with good diagnostic quality and accuracy. No major adverse events were found. The place of CT-CA in diagnostic workup for chest pain remains to be defined.