Coronary computed tomographic angiographic findings in patients with Kawasaki disease

Coronary artery aneurysms detected by computed tomography coronary angiography

Aims

Coronary artery aneurysms (CAAs) are incidentally revealed by coronary angiography and consist in a localized dilation of a coronary artery. Although invasive coronary angiography (ICA) is the gold standard imaging technique, it can lead to the underestimation of CAAs diameter in presence of parietal thrombi. Computed tomography coronary angiography (CTCA) is a very sensitive tool in CAAs detection and provides a clear visualization of coronary lumen highlighting intraluminal thrombi.

Methods and results

We retrospectively reviewed 390 CTCA performed at our institution, 9 patients (6 men, 3 women) resulted affected by CAAs and represented the aneurysmal group (A group). Matched controls were identified among the non-aneurysmal patients with healthy coronaries to CTCA (NAH group). Clinical variables and imaging findings were compared and correlated. CAAs prevalence in our population was 2.31%. 15 CAAs were detected, mainly on the right coronary artery (RCA) (9 aneurysms) followed by the left anterior descending coronary artery (LAD) (three aneurysms) and the left circumflex coronary artery (CX) (three aneurysms). In six patients (66.7%) CTCA displayed an aneurysmal thrombosis and in 5 patients (55.5%) CAAs were associated to coronary artery stenoses. A statistically significant difference was found between the diameters of coronary vessels measured in healthy segments in A and NAH group.

Conclusions

CTCA has led to a non-invasive estimation of CAAs prevalence and characterization of aneurysmal features and coronary anatomy. Overcoming ICA limitations, CTCA has provided a fine analysis of the aneurysms, also in presence of intraluminal thrombi.

The emergence of Kawasaki disease in India and China

Kawasaki disease (KD) is recognized as a leading cause of acquired heart disease in children in developed countries. Although global in distribution, Japan records the highest incidence of KD in the world. Epidemiological reports from the two most populous countries in the world, namely China and India, indicate that KD is now being increasingly recognized. Whether this increased reporting is due to increased ascertainment, or is due to a true increase in incidence, remains a matter of conjecture. The diagnosis and management of KD in developing countries is a challenging proposition. In this review we highlight some of the difficulties faced by physicians in managing children with KD in resource-constrained settings.

Assessment of Coronary Artery Aneurysms Caused by Kawasaki Disease Using Transluminal Attenuation Gradient Analysis of Computerized Tomography Angiograms

Patients with coronary artery aneurysms (CAAs) resulting from Kawasaki disease (KD) are at risk for thrombosis and myocardial infarction. Current guidelines recommend CAA diameter ≥8 mm as the criterion for initiating systemic anticoagulation. Transluminal attenuation gradient (TAG) analysis has been proposed as a noninvasive method for evaluating functional significance of coronary stenoses using computerized tomography angiography (CTA), but has not previously been used in CAA. We hypothesized that abnormal hemodynamics in CAA caused by KD could be quantified using TAG analysis. We studied 23 patients with a history of KD who had undergone clinically indicated CTA. We quantified TAG in the major coronary arteries and aneurysm geometry was characterized using maximum diameter, aneurysm shape index, and sphericity index. A total of 55 coronary arteries were analyzed, 25 of which had at least 1 aneurysmal region. TAG in aneurysmal arteries was significantly lower than in normal arteries (-23.5 ± 10.7 vs -10.5 ± 9.0, p = 0.00002). Aneurysm diameter, aneurysm shape index, and sphericity index were weakly correlated with TAG (r² = 0.01, p = 0.6; r² = 0.15, p = 0.06; r² = 0.16, p = 0.04). This is the first application of TAG analysis to CAA caused by KD, and demonstrates significantly different TAG values in aneurysmal versus normal arteries. Lack of correlation between TAG and CAA geometry suggests that TAG may provide hemodynamic information not available from anatomy alone. TAG represents a possible extension to standard CTA for KD patients who may improve thrombotic risk stratification and aid in clinical decision making.

Computed tomography predict regression of coronary artery aneurysm in patients with Kawasaki disease

BACKGROUND/PURPOSE

The study evaluated possible factors influencing the regression of coronary artery aneurysm (CAA) in patients with Kawasaki disease (KD) through electrocardiographically gated cardiac computed tomography (CT).

METHODS

18 patients with KD exhibited CAAs in at least 2 CT examinations conducted from December 2004 to September 2015, and 37 aneurysms were observed. Every aneurysm was corrected through the descending aorta at the origin level of the left main coronary artery under a normal distribution and measured under a fixed window level. These aneurysms were divided into 2 groups according to regression. Clinical symptoms, laboratory data, and imaging characteristics of both groups were analyzed.

RESULTS

All the aneurysms of 4 patients decreased in size, and totally, 14 aneurysms (37%) regressed. CAA regression tends to occur early after disease onset. No significant differences were observed in sex, aneurysm location, and the distance to the orifice between the 2 groups. The aneurysms with no calcification (p = 0.012), smaller diameter (p = 0.004), younger disease onset age (p = 0.048), and ectatic shape (p < 0.001) were more likely to regress according to univariate analysis. Receiver operating characteristic analysis revealed that the possible cut-off point of the maximal diameter to yield the highest sensitivity (91.3%) and specificity (92.9%) to predict CAA regression was 5.6 mm.

CONCLUSION

Calcified CAAs in patients with KD was less likely to regress. The aneurysm size and shape as well as disease onset age were possible factors influencing regression.

Imaging of acquired coronary diseases: From children to adults

Acquired coronary diseases include aneurysms, fistulae, dissections, and stenosis. Aneurysms may occur secondarily to Kawasaki disease, a childhood vasculitis, the prognosis of which depends on the coronary involvement, or they may be degenerative, infectious, inflammatory, or traumatic in origin. Fistulae develop between the coronary arterial system and a pulmonary or bronchial artery, or cardiac cavity. Dissections may occur spontaneously or may be post-traumatic. These coronary abnormalities may be found incidentally or may present as complications, infarction or rupture. The goals of this article are to understand acquired childhood and adult coronary diseases and their usual means of presentation, the ways of investigating them, and the principles of their treatment.