Evaluation of coronary artery stent patency by using 64-slice multi-detector computed tomography and conventional coronary angiography: A comparison with intravascular ultrasonography

Multislice computed tomography assessment of everolimus-eluting Absorb bioresorbable scaffolds in comparison with metallic drug-eluting stents from the ABSORB Japan randomised trial

AIMS

Blooming artefacts limit accurate coronary assessment by multislice computed tomography (MSCT) in metallic stents. We sought to investigate whether bioresorbable vascular scaffolds (BVS) could be better assessed by MSCT.

METHODS AND RESULTS

Among 400 patients in the randomised ABSORB Japan trial, a pre-specified MSCT substudy was performed in 98 patients (103 lesions) in the BVS arm and 49 patients (49 lesions) in the cobalt-chromium everolimus-eluting stent (CoCr-EES) arm at 13 months prior to follow-up angiography. The assessability of BVS by MSCT was superior to that of CoCr-EES (94% versus 67%, p<0.001). Blooming artefacts were the main reason CoCr-EES could not be analysed (29%), while marker artefacts precluded analysis in 1.1% of BVS. In the CoCr-EES arm, non-assessable lesions were more prevalent in segments with 2.5 mm stents compared to 3.0 or 3.5 mm stents (75.0% versus 23.5%, p=0.01), while in the BVS arm image quality was good regardless of the diameter. The in-device minimal lumen diameter by MSCT was smaller than that by QCA with a difference of 0.61 mm in the CoCr-EES arm, vs. only 0.026 mm in the BVS arm.

CONCLUSIONS

The feasibility of MSCT assessment of BVS-treated lesions was greater than that for lesions with CoCr-EES.

Multidetector computed tomography angiography to evaluate the subscapular arterial tree

OBJECTIVE

The subscapular artery has an important place in reconstructive surgery. The major pedicles of several different flaps used widely in reconstructive surgery take their roots from this arterial tree. This study aimed to provide anatomical data relating to these vessels through the use of multidetector computed tomography angiography (MDCTA) and to evaluate the clinical utility of MDCTA tool prior to surgery.

METHODS AND MATERIALS

A radiological evaluation using a MDCTA was made of the bilateral subscapular arteries and branches measuring >0.5 mm in diameter that could be sufficiently identified as vascular structures in 92 patients (44 men and 48 women) with pneumonia, pleural effusion, lung masses, or nodules for which a thoracic MDCTA was requested for the purpose of diagnosis.

RESULTS

The mean diameter of the subscapular artery origin was 3.86 ± 0.60 mm on the left and 3.93 ± 0.62 mm on the right. The mean diameter of the circumflex scapular artery origin was 2.41 ± 0.37 mm on the left and 2.44 ± 0.39 mm on the right. The mean diameter of the thoracodorsal artery origin was 2.29 ± 0.27 mm on the left and 2.31 ± 0.29 mm on the right. Mean length of the circumflex scapular artery was 46.34 ± 9.41 mm on the left and 46.10 ± 8.81 mm on the right. Mean length of the latissimus dorsi branch of the thoracodorsal artery from the origin of the subscapular artery was 110.11 ± 17.42 mm on the left and 112.21 ± 14.60 mm on the right. Mean length of the serratus anterior branch was 124.25 ± 19.00 mm on the left and 120.84 ± 15.67 mm on the right. No differences were detected between the left and right sides or between sexes. Doubled circumflex scapular arteries were found in 4.3% of patients, and the circumflex scapular artery branched directly off the axillary artery in 3.2% of patients.

CONCLUSION

This study showed that MDCTA is a highly valuable, non-invasive imaging tool for studying vascular anatomy and detecting variations in vascular structure during preoperative planning, thus enhancing surgical safety.

Computed tomography imaging of early coronary artery lesions in stable individuals with multiple cardiovascular risk factors

OBJECTIVES

To investigate the prevalence, extent, severity, and features of coronary artery lesions in stable patients with multiple cardiovascular risk factors.

METHODS

Seventy-seven patients with more than 3 cardiovascular risk factors were suspected of having coronary artery disease. Patients with high-risk factors and 39 controls with no risk factors were enrolled in the study. The related risk factors included hypertension, impaired glucose tolerance, dyslipidemia, smoking history, and overweight. The characteristics of coronary lesions were identified and evaluated by 64-slice coronary computed tomography angiography.

RESULTS

The incidence of coronary atherosclerosis was higher in the high-risk group than in the no-risk group. The involved branches of the coronary artery, the diffusivity of the lesion, the degree of stenosis, and the nature of the plaques were significantly more severe in the high-risk group compared with the no-risk group (all p < 0.05).

CONCLUSION

Among stable individuals with high-risk factors, early coronary artery lesions are common and severe. Computed tomography has promising value for the early screening of coronary lesions.

Association of cardiac events with coronary artery disease detected by 64-slice or greater coronary CT angiography: a systematic review and meta-analysis

BACKGROUND

The value of ≥64-slice coronary CT angiography (CCTA) to determine odds of cardiac death or non-fatal myocardial infarction (MI) needs further clarification.

METHODS

We performed a systematic review and meta-analysis using publications reporting events/severity of coronary artery disease (CAD) in patients with suspected CAD undergoing CCTA. Patients were divided into: no CAD, non-obstructive CAD (maximal stenosis <50%), and obstructive CAD (≥50% stenosis). Odds ratios with 95% confidence intervals were calculated using a fixed or random effects model. Heterogeneity was assessed using the I(2) index.

RESULTS

We included thirty-two studies comprising 41,960 patients with 363 all-cause deaths (15.0%), 114 cardiac deaths (4.7%), 342 MI (14.2%), 69 unstable angina (2.8%), and 1527 late revascularizations (63.2%) over 1.96 (SD 0.77) years of follow-up. Cardiac death or MI occurred in 0.04% without, 1.29% with non-obstructive, and 6.53% with obstructive CAD. OR for cardiac death or MI was: 14.92 (95% CI, 6.78 to 32.85) for obstructive CAD, 6.41 (95% CI, 2.44 to 16.84) for non-obstructive CAD versus no CAD, and 3.19 (95% CI, 2.29 to 4.45) for non-obstructive versus obstructive CAD and 6.56 (95% CI, 3.07 to 14.02) for no versus any CAD. Similar trends were noted for all-cause mortality and composite major adverse cardiovascular events.

CONCLUSIONS

Increasing CAD severity detected by CCTA is associated with cardiac death or MI, all-cause mortality, and composite major adverse cardiovascular events. Absence of CAD is associated with very low odds of major adverse events, but non-obstructive disease significantly increases odds of cardiac adverse events in this follow-up period.

Coronary pressure-derived fractional flow reserve in the assessment of coronary artery stenoses

OBJECTIVES

Catheter-based angiography is the reference-standard to establish coronary anatomy. While routinely employed clinically, lumen assessment correlates poorly with physiological measures of ischaemia. Moreover, functional studies to identify and localise ischaemia before elective angiography are often not available. This article reviews fractional flow reserve (FFR) and its role in guiding patient management for patients with a potentially haemodynamic significant coronary lesion.

METHODS

This review discusses the theory, evidence, indications, and limitations of FFR. Also included are emerging non-invasive imaging FFR surrogates currently under evaluation for accuracy with respect to standard FFR.

RESULTS

Coronary pressure-derived fractional flow reserve (FFR) rapidly assesses the haemodynamic significance of individual coronary artery lesions and can readily be performed in the catheterisation laboratory. The use of FFR has been shown to effectively guide coronary revascularization procedures leading to improved patient outcomes.

CONCLUSIONS

FFR is an invaluable modality in guiding coronary disease treatment decisions. It is safe, cost-effective and leads to improved patient outcomes. Non-invasive imaging modalities to assess the physiologic significance of CAD are currently being  developed and evaluated.