Audrey Dionne

Coronary Wall Structural Changes in Patients With Kawasaki Disease: New Insights From Optical Coherence Tomography (OCT).

Background Coronary artery aneurysms (CAA) are serious complications of Kawasaki disease (KD). Optical coherence tomography (OCT) is a high-resolution intracoronary imaging modality that characterizes coronary artery wall structure. The purpose of this work was to describe CAA wall sequelae after KD. Methods and Results KD patients scheduled for routine coronary angiography underwent OCT imaging between March 2013 and August 2014. Subjects’ clinical courses, echocardiography, and coronary angiography examinations were reviewed retrospectively. OCT was performed in 18 patients aged 12.4±5.5 years, 9.0±5.1 years following onset of KD. Of those, 14 patients (77.7%) had a history of CAA (7 with giant CAA and 7 with regressed CAA at time of OCT). Intracoronary nitroglycerin was given to all patients (88.4±45.5 μg/m2). Mean radiation dose was 10.9±5.2 mGy/kg. One patient suffered from a transitory uneventful vasospasm at the site of a regressed CAA; otherwise no major procedural complications occurred. The most frequent abnormality observed on OCT was intimal hyperplasia (15 patients, 83.3%) seen at both aneurysmal sites and angiographically normal segments amounting to 390.8±166.0 μm for affected segments compared to 61.7±17 μm for unaffected segments (P<0.001). Disappearance of the media, and presence of fibrosis, calcifications, macrophage accumulation, neovascularization, and white thrombi were seen in 72.2%, 77.8%, 27.8%, 44.4%, and 33.3% of patients. Conclusions In this study, OCT proved safe and insightful in the setting of KD, with the potential to add diagnostic value in the assessment of coronary abnormalities in KD. The depicted coronary structural changes correspond to histological findings previously described in KD.

Aspirin Dose and Prevention of Coronary Abnormalities in Kawasaki Disease

This study suggests that low-dose ASA in KD is not inferior to higher doses in reducing the risk of CA abnormalities. BACKGROUND: Acetylsalicylic acid (ASA) is part of the recommended treatment of Kawasaki disease (KD). Controversies remain regarding the optimal dose of ASA to be used. We aimed to evaluate the noninferiority of ASA at an antiplatelet dose in acute KD in preventing coronary artery (CA) abnormalities. METHODS: This is a multicenter, retrospective, nonrandomized cohort study including children 0 to 10 years of age with acute KD between 2004 and 2015 from 5 institutions, of which 2 routinely use low-dose ASA (3–5 mg/kg per day) and 3 use high-dose ASA (80 mg/kg per day). Outcomes were CA abnormalities defined as a CA diameter with a z score ≥2.5. We assessed the risk difference of CA abnormalities according to ASA dose. All subjects received ASA and intravenous immunoglobulin within 10 days of fever onset. RESULTS: There were 1213 subjects included, 848 in the high-dose and 365 in the low-dose ASA group. There was no difference in the risk of CA abnormalities in the low-dose compared with the high-dose ASA group (22.2% vs 20.5%). The risk difference adjusted for potential confounders was 0.3% (95% confidence interval [CI]: −4.5% to 5.0%). The adjusted risk difference for CA abnormalities persisting at the 6-week follow-up was −1.9% (95% CI: −5.3% to 1.5%). The 95% CI of the risk difference of CA abnormalities adjusted for confounders was within the prespecified 5% margin considered to be noninferior. CONCLUSIONS: In conjunction with intravenous immunoglobulin, low-dose ASA in acute KD is not inferior to high-dose ASA for reducing the risk of CA abnormalities.

Fatal Kawasaki disease with incomplete criteria: Correlation between optical coherence tomography and pathology

Coronary artery aneurysm is a serious complication of Kawasaki disease (KD). A 3‐month‐old infant presented with severe KD 27 days after onset of fever. The patient presented with shock, inferolateral ischemia on electrocardiogram and high troponin. Echocardiography showed severe myocardial dysfunction with diffuse coronary dilation and right coronary artery aneurysm. Arterial Doppler demonstrated thrombosis of aneurysmal axillary and iliac arteries. Withdrawal of support was implemented due to multi‐organ failure. Post‐mortem optical coherence tomography correlated with pathology. The pulmonary artery was normal on OCT and histology. Coronary arteries showed aneurysmal dilatation, with intimal hyperplasia and preserved media on OCT. Pathology confirmed these findings, with destruction of the internal elastic lamina, luminal myofibroblastic proliferation, neovascularization, and partial disappearance of the media. This is the first report of pathologic correlation in KD with OCT at the subacute stage, which adequately identified structural wall changes.

Myocarditis and Kawasaki disease

Kawasaki disease (KD) is the most common vasculitis of childhood. Coronary artery aneurysms and myocarditis are common cardiovascular complications of KD. While evidence of myocarditis can be found in all patients with KD on histology specimens, only a minority of patients are clinically symptomatic. Occasionally children can present with KD shock syndrome and hemodynamic instability as a result of decreased systolic function and vasoplegia. Several children with KD have depressed shortening fraction on echocardiography. Increased end‐systolic and end‐diastolic dimensions, strain abnormalities and diastolic dysfunction are also found in a significant proportion of patients. Echocardiographic signs of myocarditis improve after the acute phase and do so more quickly in patients who have received intravenous immunoglobulins, as opposed to those given only aspirin. Normalization of systolic function is typically observed over long‐term follow‐up; however, more subtle abnormalities (strain, diastolic function) may persist. It is noteworthy that myocarditis associated with KD can occur in absence of coronary artery abnormalities. KD myocarditis can result in long‐term sequelae.

Importance of anatomical dominance in the evaluation of coronary dilatation in Kawasaki disease

Introduction In Kawasaki disease, although coronary dilatation is attributed to vasculitis, the effect of myocardial inflammation is underestimated. Coronary dilatations are determined by Z-scores, which do not take into account dominance. The aim of the present study was to describe the impact of coronary dominance on dilatation in Kawasaki disease. METHODS We performed a retrospective analysis of coronary dilatations according to angiography categorisation of dominance. RESULTS Of 28 patients (2.6 [0.2-10.1] years), right dominance was present in 15 patients and left in 13. Early dilatation was present in all patients, of whom 11 were ipsilateral to the dominant segment and 17 contralateral. Ipsilateral dilatations were present at diagnosis (9/11 versus 6/17, p=0.02) compared with contralateral dilatations, which developed 2 weeks after diagnosis (9/11 versus 16/17, p=0.29). Coronary artery Z-scores of patients with contralateral dilatation increased at 2 weeks, before returning to baseline values (2.0±2.2 at diagnosis, 4.1±1.8 at 2 weeks, 1.8±1.2 at 3-6 months, p=0.001), compared with patients with ipsilateral dilatation in whom Z-scores were maximal at diagnosis and remained stable (3.0±0.9, 2.7±1.1 and 2.6±1.5, respectively, p=0.13). Dominant coronary artery Z-scores were higher compared with non-dominant segments at diagnosis (3.0±0.9 versus 1.0±0.8, p<0.001) and at late follow-up (2.6±1.5 versus 0.4±1.4, p=0.002) in patients with ipsilateral dilatation. CONCLUSION Progression of coronary dilatation after diagnosis may be a sign of dilatation secondary to vasculitis, as opposed to regression of Z-scores in ipsilateral dilatations, probably related to physiological vasodilatation in response to carditis. This needs to be validated in larger studies against vasculitic and myocardial inflammatory markers.

N-terminal pro-B-type natriuretic peptide diagnostic algorithm versus American Heart Association algorithm for Kawasaki disease

Diagnosis of Kawasaki disease (KD) can be challenging in the absence of a confirmatory test or pathognomonic finding, especially when clinical criteria are incomplete. We recently proposed serum N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP) as an adjunctive diagnostic test.

Profile of resistance to IVIG treatment in patients with Kawasaki disease and concomitant infection

Introduction Kawasaki disease (KD) can be associated with concomitant viral or bacterial infections. Children with persistent or recurrent fever 36 hours after the end of intravenous immunoglobulin (IVIG) are considered to be resistant to treatment and are at increased risk for coronary complications. Although concomitant infection does not affect coronary outcome, it is unknown how it influences the response to IVIG treatment. Methodology Retrospective cohort study between 2008 and 2016 in a tertiary pediatric university hospital, including 154 children, of which 59 (38%) had concomitant infection. Results Children with concomitant infection were more likely to have fever 48 hours after initial IVIG treatment (36% vs 20%, p = 0.05) and to be treated with a second dose (33% vs 18%, p = 0.04). Children with infection had higher C-reactive protein at the time of diagnosis (148 vs 112 mg/L, p = 0.04), and 48 hours after IVIG administration (111 vs 59 mg/L, p = 0.003). Nevertheless, there was no statistically significant difference in the prevalence of coronary complications (Z-score > 2.5) between children with and without concomitant infection (36% vs 39%, p = 0.68). Conclusion Children with KD and concomitant infection are more likely to have persistent fever and elevated inflammatory markers after treatment. This association increases the likelihood of receiving a second dose of IVIG but not the risk of coronary complication. Accordingly, prospective studies to distinguish true IVIG resistance from infection induced persistent fever is warranted.

A Decade of NT-proBNP in Acute Kawasaki Disease, from Physiological Response to Clinical Relevance

Kawasaki disease (KD) is an inflammatory febrile illness of early childhood and the primary cause of acquired heart disease during childhood. Coronary artery aneurysms (CAA) are a serious complication of KD, leading to ischemic heart disease, myocardial infarction, and sudden cardiac death. Timely diagnosis in the first ten days of fever is crucial to reduce the risk of coronary artery complications. Nitrogen-terminal B-type natriuretic peptide (NT-proBNP), originally used for the management of adults with heart disease, was shown to be useful in the diagnosis and management of patients with KD. NT-proBNP is released by cardiomyocytes in response to mechanical factors such as the dilation of cardiac chambers, and to pro-inflammatory cytokines. The utility of NT-proBNP as a biological marker in KD is based on the universal myocardial inflammatory component early in the course of the disease. Patients with KD have higher NT-proBNP at the time of diagnosis than febrile controls, with a pooled sensitivity of 89% (95% confidence interval 78⁻95), and a specificity of 72% (95% confidence interval 58⁻82). The positive likelihood ratio is 3.2:1 (95% confidence interval 2.1⁻4.8). Moreover, patients with resistance to intravenous immunoglobulin treatment and CAA were found to have higher levels of NT-proBNP, suggesting a prognostic role. Nevertheless, the non-specificity of NT-proBNP to KD limits its use as a stand-alone test. In this light, a tentative associative retrospective diagnostic algorithm was highly reliable for including all cases at risk of CAA, which warrants further prospective studies for a better diagnostic index of suspicion and risk stratification of patients.