Newer Concepts Regarding Adults With Coronary Artery Aneurysms: Are They All Kawasaki? Does It Make a Difference?

Emergence and Characterization of Acute Coronary Syndrome in Adults After Confirmed or Missed History of Kawasaki Disease in Japan: A Japanese Nationwide Survey

Background: Acute coronary syndrome (ACS), which is emerging in adults long after confirmed (followed-up or lost-to-follow), or missed Kawasaki disease (KD), is poorly characterized. Methods and Results: A Japanese retrospective nationwide hospital-based questionnaire survey of ACS during 2000-09 was conducted to characterize such patients. Among a total of 67 patients (median age 35, male 76%) recruited, low conventional coronary risks (≤1/6) was noted in 75%, a diagnosis of ST-elevation and myocardial infarction or cardiac arrest in 66%, medication before ACS in 22% (warfarin in 4%), and no prior history of acute myocardial infarction in 94%. One-month mortality was 19%. KD diagnosis was made in 32 during acute illness (Group A), in which 17 were lost to follow, and retrospectively in the other 35 from coronary imaging at ACS (Group B). Group A developed ACS at lower coronary risks (≤2/5 in 87 vs. 65% in group B, p = 0.043) at a younger age (26.5 vs. 40 yo, p < 0.001). In group A, followed-up patients developed ACS under medication before ACS (87 vs. 0% in lost-to-follow patients, p < 0.001) for giant aneurysm in culprit lesions (69 vs. 29%, p = 0.030). One-month mortality was comparable between groups A and B, and between patients followed-up and lost-to-follow in group A. The culprit lesion in group A was characterized by the association of an aneurysm ≥6 mm in acute KD (100%), lack of significant stenosis (61%) or giant aneurysm (50%) in the long-term (median interval 16 y), and the presence of intravascular ultrasound-derived calcification at ACS (86%). Conclusions: The present retrospective nationwide questionnaire survey demonstrated nationwide emergence of initial ACS in young adults at low coronary risks, who are followed-up or lost-to-follow after confirmed KD and initial coronary aneurysms ≥6 mm.

Embryology of coronary arteries and anatomy/pathophysiology of coronary anomalies. A comprehensive update

OBJECTIVES

This paper reviews new findings in both embryology of coronary arteries and in clinical observations of coronary artery anomalies.

FOCUS

Our presentation emphasizes studies based on: 1) newer methods of coronary development in animals and humans, and 2) intravascular ultrasonography to interpret pathophysiology and guide treatment of coronary anomalies.

CONCLUSIONS

New data reveal the roles of many cellular interactions and signaling pathways involved in the normal and abnormal formation of the coronary arterial system and the consequences of their defective formation. Pathogenetic developmental mechanisms include dysfunction of the Notch and Hypo signaling pathways, angiogenic and arteriogenic molecules, and neural crest cells. We addressed numerous clinically significant coronary anomalies and their prevalence in a general population (especially those characterized by an ectopic origin with aortic intramural course), and point out the critical relevance of understanding the variable mechanisms of coronary dysfunction, especially, fixed versus phasic stenoses or intermittent spasm, and individual severity of clinical presentations.

Association between ascending aortic diameter and coronary artery dilation: a demographic data analysis

Objective

Coronary artery dilations (CDs), a subgroup of coronary artery anomalies (CAAs), are relatively rare but important cardiac pathologies. They are considered to be linked to coronary atherosclerosis in most cases.

Methods

The demographic data, multi-slice computed tomographic coronary angiography data, coronary calcium score, and ascending aortic diameter (AAD) of 1538 patients were reviewed. In total, 197 (12.8%) patients (166 men, 31 women; age 15 – 84 years; mean 55.78 ± 12.32 years) with CAAs were identified, and 81 (5.3%) patients (70 men, 11 women; age 27 – 80 years; mean 56.63 ± 12.06 years) had CDs. Multiple regression and correlation analyses were performed in all 1538 patients to predict the association between the AAD and the presence of CD and thus their correlation with atherosclerosis.

Results

The AAD was significantly larger in patients with than without CAAs and CDs. Male sex was significantly more prevalent in patients with CAAs and CDs. According to the multiple logistic regression model, male sex increased the risk of CD by 2.650 and the risk of CAA by 2.017, while hyperlipidaemia decreased the risk of CAA by 0.681. While a moderately weak correlation between the AAD and age was observed in patients with CDs, no correlation was found between the AAD and coronary calcium score.

Conclusion

Although the natural history and physiopathology of CDs is not yet fully understood, the present study shows an association between the AAD and the presence of CDs but a lack of association between atherosclerosis and CDs.

Cardiac Complications in 38 Cases of Kawasaki Disease with Coronary Artery Aneurysm Diagnosed by Echocardiography

BACKGROUND

The long-term prognosis of patients with Kawasaki disease (KD) complicated by coronary artery aneurysm (CAA) is unclear. The aim of this study was to evaluate the complications of KD with CAAs.

METHOD

We retrospectively analyzed the clinical data and complications of 38 KD patients with CAAs who were treated and underwent regular follow-up with echocardiography between January 1989 and May 2013.

RESULTS

During a period of 29 days to 19 years after disease onset, complications seen included coronary stenosis and occlusion (six patients), thrombosis (17 patients), myocardial infarction (six patients), and calcification of CAAs (seven patients). Rupture of giant CAAs occurred in two patients and caused sudden death in one of these patients at 29 days and in the other patient at 5 months after disease onset. A total of seven deaths occurred, with five deaths caused by myocardial infarction. Three of these had undiagnosed incomplete KD or had not received regular treatment, while two experienced sudden death after several asymptomatic myocardial infarctions.

CONCLUSION

Cardiac complications of KD with CAAs include thrombosis, coronary stenosis, myocardial infarction, sudden death, and calcification. Although rare, rupture of giant CAAs is fatal and might occur earlier after the onset of disease. Mortality occurred primarily in the earlier cases when anticoagulant therapy was insufficient and in patients who did not receive regular treatment. Echocardiography can provide reliable information for assessing the progression and prognosis of this condition.

Long-term management of Kawasaki disease: implications for the adult patient

Coronary artery complications from Kawasaki disease (KD) range from no involvement to giant coronary artery aneurysms (CAA). Current long-term management protocols are calibrated to the degree of maximal and current coronary artery involvement reflecting the known likelihood of severe long-term cardiac complications. It has recently been suggested that all KD patients may be at potential risk of severe long-term cardiac complications. If this assertion was to be confirmed, current follow-up protocols would need to be extensively modified, with important implications both for the growing adult population with a previous history of KD and for the healthcare system. Based on the available evidence, patients with multiple large and/or giant CAA are at substantial risk of severe long-term cardiac complications and should have regular specialized follow-up. Patients with transient or no CAA have not been reported to be at risk of severe long-term cardiac complications. The influence of KD on the atherosclerotic process remains suboptimally defined, and should be the focus of future studies. Heightened cardiovascular risk factor surveillance and management is recommended regardless of coronary artery involvement. Based on the currently available evidence, existing long-term management protocols seem to be appropriately calibrated to the level of risk. Revised long-term management protocols should incorporate newer, noninvasive imaging methods and intensive management of atherosclerotic risk. There is insufficient evidence at this time to mandate long-term specialized follow-up and invasive testing for patients who have not had CAA.