Multi-slice computed tomography coronary angiography: anatomic vs functional assessment in clinical practice.

Non-invasive imaging plays an increasingly important role in the diagnosis and risk stratification of coronary artery disease (CAD). Several techniques such as stress echocardiography and myocardial perfusion imaging have become available to assess cardiac function and myocardial perfusion. With the arrival of multi-slice computed tomography coronary angiography (CTA), non-invasive imaging of coronary anatomy has also become possible. Studies concerning the diagnostic accuracy have demonstrated a good agreement with conventional coronary angiography resulting in a sensitivity and specificity of approximately 86% and 96%, respectively. The high negative predictive value of 97% renders it particularly useful to rule out the presence of CAD in patients with an intermediate pretest likelihood. Moreover, comparative studies have demonstrated that anatomic imaging with CTA may provide information complementary to the traditionally used techniques for functional assessment. From these studies can be derived that only approximately 50% of significant stenoses on CTA are functionally relevant; a large proportion of significant (>50%) lesions on CTA does not result in perfusion abnormalities. Alternatively, many patients with a normal perfusion CTA show considerable atherosclerosis on CTA. Therefore, the combined use of these techniques may enhance the assessment of the presence and extent of CAD. In the future diagnostic algorithms, combining non-invasive anatomic and functional imaging need to be evaluated in large patient populations to establish their efficacy, safety, and cost effectiveness. Importantly, these investigations should result in the development of comprehensive guidelines on the use of CTA in clinical practice as well.

Multislice computed tomography coronary angiography for risk stratification in patients with an intermediate pretest likelihood.

OBJECTIVES: To assess whether multislice computed tomography coronary angiography (MSCTA) may be useful for risk stratification of patients with suspected coronary artery disease (CAD) at intermediate pretest likelihood according to Diamond and Forrester. DESIGN AND PATIENTS: MSCTA images were evaluated for the presence of significant CAD in 316 patients with suspected CAD (60% male, average (SD) age 57 (11) years) and an intermediate pretest likelihood according to Diamond and Forrester. Patients were followed up to determine the occurrence of an event. MAIN OUTCOME MEASURES: A combined end point of all-cause mortality, non-fatal infarction and unstable angina requiring revascularisation. RESULTS: Significant CAD was seen in 89 patients (28%), whereas normal MSCTA or non-significant CAD was seen in the remaining 227 (72%) patients. During follow-up (median 621 days (25-75th centile 408-835) an event occurred in 13 patients (4.8%). The annualised event rate was 0.8% in patients with normal MSCT, 2.2% in patients with non-significant CAD and 6.5% in patients with significant CAD. Moreover, MSCTA remained a significant predictor (p<0.05) of events after multivariate correction (hazard ratio = 3.460 (95% CI 1.142 to 10.480). CONCLUSIONS: The results suggest that in patients with an intermediate pretest likelihood, MSCTA is highly effective in re-stratifying patients into either a low or high post-test risk group. These results further emphasise the usefulness of non-invasive imaging with MSCTA in this patient population.

Gender influence on the diagnostic accuracy of 64-slice multislice computed tomography coronary angiography for detection of obstructive coronary artery disease.

OBJECTIVE: To compare the diagnostic accuracy of 64-slice multislice computed tomography (MSCT) coronary angiography between female and male patients using conventional coronary angiography as the reference standard. DESIGN: Diagnostic accuracy study. SETTING: University hospital. PATIENTS: 103 consecutive patients (51 men, 52 women, mean (SD) age 60 (10) years) with known and suspected coronary artery disease underwent 64-slice MSCT. MAIN OUTCOME MEASURES: Diagnostic accuracy of 64-slice MSCT to detect obstructive (>or=50% luminal narrowing) stenoses in men and women. RESULTS: One male and two female patients were excluded from the analysis owing to non-diagnostic MSCT scans as a result of increased heart rate and breathing during the scan. Accordingly, on segmental level, 728/762 coronary segments were of sufficient quality in women (96% (95% CI 95% to 97%)) and 704/723 segments were interpretable in men (97% (95% CI 96% to 98%)). In the remaining 100 patients included in the further analyses, the sensitivity and specificity on a segmental level in women and men were 85% (95% CI 75% to 95%) vs 85% (95% CI 78% to 92%) and 99% (95% CI 98% to 100%) vs 99% (95% CI 98% to 100%), respectively. On a patient level, the sensitivity in women and men was 95% (95% CI 87% to 100%) vs 100%, specificity 93% (95% CI 83% to 100%) vs 89% (95% CI 74% to 100%), positive predictive value 91% (95% CI 79% to 100%) vs 94% (95% CI 86% to 100%), and negative predictive value 96% (95% CI 89% to 100%) vs 100%, respectively. CONCLUSION: The findings confirm the high diagnostic accuracy of 64-slice MSCT coronary angiography in both male and female patients.