Images in cardiology. Delayed appearance of coronary aneurysms in Kawasaki disease

Late Coronary Aneurysm Formation after Kawasaki Disease: a Review of Mechanistic and Clinical Aspects

Evolution of coronary artery aneurysms (CAAs) has been an ominous clinical finding in patients with Kawasaki disease (KD). CAAs generally emerge within the first few weeks in patients with KD, and appear to be strongly associated with the failure to timely initiate specific management strategies. CAA formation might occasionally arise as a late-onset phenomenon long after the index KD episode. Late CAAs in the setting of KD have particular mechanistic and clinical characteristics. Late CAAs in the setting of KD may be confused with other CAA types (atherosclerotic, etc.), and are possibly underdiagnosed in clinical practice.

In patients with Kawasaki disease (KD), evolution of coronary artery aneurysms (CAAs) generally emerges within the first few weeks after disease onset. However, CAA formation in these patients might occasionally arise as a late-onset phenomenon after a long latent period. Characteristically, late CAAs manifest as new-onset vascular pathologies or expansion of long-stable CAAs on coronary imaging modalities, and might have diverse mechanistic and clinical implications. Accordingly, the present paper aims to focus on late CAA formation and its implications in the setting of KD.

Vascular health late after Kawasaki disease: implications for accelerated atherosclerosis

Kawasaki disease (KD), an acute vasculitis that primarily affects young children, is the most common acquired paediatric cardiovascular disease in developed countries. While sequelae of arterial inflammation in the acute phase of KD are well documented, its late effects on vascular health are increasingly unveiled. Late vascular dysfunction is characterized by structural alterations and functional impairment in term of arterial stiffening and endothelial dysfunction and shown to involve both coronary and systemic arteries. Further evidence suggests that continuous low grade inflammation and ongoing active remodeling of coronary arterial lesions occur late after acute illness and may play a role in structural and functional alterations of the arteries. Potential importance of genetic modulation on vascular health late after KD is implicated by associations between mannose binding lectin and inflammatory gene polymorphisms with severity of peripheral arterial stiffening and carotid intima-media thickening. The changes in cholesterol and lipoproteins levels late after KD further appear similar to those proposed to be atherogenic. While data on adverse vascular health are less controversial in patients with persistent or regressed coronary arterial aneurysms, data appear conflicting in individuals with no coronary arterial involvements or only transient coronary ectasia. Notwithstanding, concerns have been raised with regard to predisposition of KD in childhood to accelerated atherosclerosis in adulthood. Until further evidence-based data are available, however, it remains important to assess and monitor cardiovascular risk factors and to promote cardiovascular health in children with a history of KD in the long term.

Two cases of new coronary aneurysms that developed in the late period after Kawasaki disease

Two cases of coronary aneurysm developed in the late period after Kawasaki disease (KD). Case 1 involved a 13-year-old boy who had aneurysms develop after a diagnosis of complete regression. Case 2 involved a 29-year-old man who had a new aneurysm develop after he was older than 20 years. Physicians need to be aware that coronary aneurysms can develop in patients with antecedent KD even after regression or in adulthood.

Coronary artery calcifications in the long-term follow-up of Kawasaki disease

BACKGROUND

To determine if detection of coronary artery calcifications in patients with Kawasaki disease may serve as a noninvasive predictor of future coronary artery events.

METHODS

A prospective, cohort pilot study that included 18 patients with Kawasaki disease > 1 year from the acute disease was performed including 9 patients with coronary abnormalities during the acute illness (Group 1) and 9 without coronary abnormalities (Group 2). Patients were classified by echocardiography as having none, resolved, or residual coronary artery abnormalities. Electron beam computed tomography (EBCT) scans were completed using the Agatson coronary calcium scoring system. Intermediate follow-up was performed 2.5 years after EBCT to determine if clinically significant coronary artery events (myocardial infarction or sudden death) had occurred.

RESULTS

Late echocardiographic abnormalities corresponded with the early echocardiographic abnormalities in 5 of 9 patients (P = .029) in Group 1. The late echocardiographic abnormalities significantly correlated with detection of calcifications by EBCT in 4 of 5 patients (95% CI 28%-99%). One patient with residual coronary abnormalities and coronary artery calcifications with the highest calcium score subsequently had a sudden death. Detection of coronary artery calcifications may be predictive of sudden death (P = .056). No residual echocardiographic abnormalities, coronary artery calcifications, or coronary artery events occurred in Group 2 patients.

CONCLUSIONS

Patients with Kawasaki disease with residual coronary abnormalities show EBCT evidence of coronary artery calcifications. Detection of coronary artery calcifications may be useful for risk stratification in the long-term management of patients with Kawasaki disease.

Dilated coronary arterial lesions in the late period after Kawasaki disease

OBJECTIVES

There are two types of late coronary dilated lesions after Kawasaki disease: new aneurysms and expanding aneurysms. The development of coronary dilated lesions late after Kawasaki disease was investigated.

METHODS

Between 1978 and 2003, 562 patients with coronary arterial lesions underwent selective coronary angiography on at least two occasions.

RESULTS

Of the 562 patients studied, 17 new dilated or expanding lesions were found in 15 patients (3%, 11 boys, four girls). The time of detection of new aneurysms after Kawasaki disease ranged from 1.9-19.2 years (median 11.4 years) and their diameters ranged from 2.0-6.5 mm (median 4.4 mm). Thirteen new aneurysms occurred in vessels in which previous aneurysms had regressed and all new aneurysms were associated with localised stenosis. A new aneurysm at the bifurcation or in the branches was seen in 14 (93%) and 13 were eccentric (87%). Of two expanding aneurysms, one involved the right coronary artery in one patient and the other the left anterior descending coronary artery. One expanding aneurysm increased from 4.4 mm to 19.5 mm over 17 years, and the other expanding aneurysm increased from 10 mm to 15 mm in one year.

CONCLUSIONS

Neither new nor expanding aneurysms have caused cardiac events. New aneurysms often develop as a pre-stenotic or post-stenotic dilatation secondary to localised stenosis. New and expanding aneurysms may be caused by haemodynamic factors in addition to the abnormality of the coronary arterial wall after severe acute vasculitis. Coronary arterial wall abnormalities were stenosis as well as, rarely, dilatation of the vessels in the late period. It is important to recognise that the changes of the coronary arterial wall persist late after regression of a large aneurysm.