Recurrent events of acute coronary syndrome in young adult patients after Kawasaki disease.

OBJECTIVE: I encountered three adult patients with major coronary artery occlusion after Kawasaki disease in childhood, who had developed again acute coronary syndrome of adults in the peripheral branches, such as the 4th segments, the atrioventricular node artery, and the posterior descending artery, of the right coronary artery. METHODS: I reviewed their clinical course and coronary angiograms. RESULTS: Their age at onset of acute coronary syndrome ranged from 29 to 33 years. The male patient with a previous anteroseptal myocardial infarction in children had a symptomatic occlusion of the branch of the 4th posterior descending artery at 32 years of age. Acute coronary syndrome occurred in the area of 4th atrioventricular node artery in two female patients. The collateral arteries from the circumflex artery to the 4th atrioventricular node arteries were not clearly injected. It was suspected that they had developed bilateral giant aneurysms after acute Kawasaki disease. Two patients had an acute myocardial infarction due to thrombotic occlusion in a giant aneurysm of the right coronary artery or the left anterior descending artery, and one patient had an asymptomatic coronary occlusion of the right coronary artery and left anterior descending artery in children. CONCLUSION: Occlusion of peripheral coronary arteries in adulthood can occur in patients with multi-vessel disease caused by Kawasaki disease. Recurrent events of acute coronary syndrome can occur in adults, although its prevalence may be low. Careful follow-up in adults is also needed in this population.

Clinical Course and Outcomes in Patients with Left Ventricular Dysfunction Due to Myocardial Infarction After Kawasaki Disease.

Long-term outcomes of patients with left ventricular dysfunction after Kawasaki disease (KD) remain unknown. The clinical course of 37 patients (29 males 8 females) with left ventricular ejection function (LVEF) less than 45% after KD since 1978 was retrospectively investigated. Cardiac events in this study were defined as admissions because of heart failure, fatal ventricular arrhythmias, heart transplantation, and death. Their ages when evaluated ranged from 1 to 70 years (median 35 years). The onset of KD ranged from 2 months to 20 years (median 21 months). All patients had bilateral coronary artery lesions, and multi-vessel occlusion occurred in 31 patients (84%). Previous myocardial infarction (MI) was found in 28 patients (76%). The interval from the onset of acute KD to the initial MI ranged from 15 days to 25 years (median 3 months). Reperfusion therapy was successful in 6 patients (30%), and coronary artery bypass grafting was performed in 23 patients (62%). Non-sustained ventricular tachycardia and fatal ventricular arrhythmias were detected in 11 patients and 22 patients, respectively. There were 15 deaths (41%). The 20-year and 50-year survival rates after KD were 84% (95% CI 67-92) and 54% (34-73), respectively (n = 37). The 30-year cardiac event-free rate after the detection of low LVEF was 42% (95% CI 27-59). The cutoff point of the left ventricular end-diastolic dimension for cardiac events was 65 mm. Patients with low LVEF had fatal ventricular arrhythmias and a worsening of their ischemic cardiomyopathy after 30 years of age and their outcomes were poor.

Long-term results of large common iliac artery aneurysms caused by Kawasaki disease in four patients.

Among Kawasaki disease patients with systemic artery aneurysms, the brachial and internal iliac arteries are the most commonly affected, and occlusions of both arteries are often found. However, the long-term fate of large common iliac artery aneurysms remains unknown, because their prevalence is very low. The long-term outcomes of common iliac artery aneurysms caused by Kawasaki disease in four patients (three females, one male) were investigated retrospectively based on their medical records and angiograms. Their ages ranged from 30 to 36 years-old. The onset age of Kawasaki disease ranged from 4 to 8 months, and the interval from the onset of Kawasaki disease to the latest angiogram ranged from 17 to 21 years. All patients had bilateral large coronary aneurysms and common iliac artery aneurysms with maximal diameters greater than 10 mm. Although all patients had multi-vessel coronary artery stenotic lesions and systemic artery aneurysms, they were asymptomatic. The three female patients underwent coronary artery bypass grafting, and the male patient underwent replacement of artificial vessels for large bilateral common iliac artery aneurysms at 3 years old of age. Over the long-term, common iliac artery aneurysms greater than 10 mm persisted as calcified aneurysms. However, they had no symptoms due to their common iliac artery aneurysms, and their ankle brachial pressure index was preserved, even if the stenosis of the common iliac artery developed as a late outcome, because the collateral arteries were well developed. The progression of stenosis of the common iliac artery after Kawasaki disease was slower.

Characteristics and long-term outcome for congenital left main coronary artery atresia.

The prevalence of congenital left main coronary artery atresia is very low. We report the characteristics and long-term outcomes of four children with left main coronary artery atresia. Three patients had heart murmurs due to mitral regurgitation at less than 1 year old. Their myocardial ischaemia worsened on exercise with aging. In the fourth patient, hypertrophic cardiomyopathy and Noonan syndrome were suspected at 1 year old. The development of communicating arteries between the conus branch and the left anterior descending artery was detected at 7 years old. The left main coronary artery atresia was confirmed by a selective coronary angiogram at 15 years old. Congenital left main coronary artery atresia could not be diagnosed by two-dimensional echocardiography; however, the left coronary arteries were small. Two patients underwent coronary artery bypass grafting of the left anterior descending artery using the left internal thoracic artery at 3 years and 6 years old, respectively. Two patients had an angioplasty with a cut back at the orifice of the left coronary artery at 2 years old and 17 years old, respectively. Two patients had no cardiac events without medication for more than 30 years after the operation. We must differentiate the diagnosis of left main coronary artery atresia in the small left coronary arteries with mitral regurgitation during the first year. Coronary artery revascularisation and mitral annuloplasty are needed. The long-term outcome of both coronary artery bypass grafting and angioplasty were good. The degree of mitral regurgitation after surgery may affect the prognosis.

Long-term results of percutaneous transluminal coronary rotational atherectomy for localised stenosis caused by Kawasaki disease.

Thirteen boys and one girl, 5-30 years (median 13 years), underwent percutaneous transluminal coronary rotational atherectomy. The interval from the onset of Kawasaki disease to PTCRA ranged from 5 to 29 years (median 12 years). The follow-up period was 1-22 years (median 13 years). The target vessels were the right coronary artery (7), left anterior descending artery (3), left circumflex (2), and left main trunk (2). The maximum burr size used was 1.75 mm in four, 2.00 mm in four, and 2.15 mm in six. The immediate results of rotational atherectomy were successful in all patients, and the mean stenosis degree improved from 86 ± 15% (mean ± standard deviation) to 37 ± 14% (p < 0.001). Cardiac events in the late period were found in four patients (29%). Acute myocardial infarction occurred in two, and syncope and ventricular fibrillation in one each. The cardiac event-free rate at 10 and 20 years was 79% (95% confidence interval 50-92) and 39% (6-87), respectively, (n = 14). The overall 20-year patency rate was 54% (95% CI 28-78). That in patients more than 10 years old was 77% (95% CI 42-94, n = 10). PTCRA alone is suitable for severe localised stenosis with calcification caused by KD in young adults except for small children. Re-stenosis within the first year after PTCRA often develops because of reactive intimal thickening after the procedure. If a target vessel is a patent 1 year after the procedure, long-term patency may be expected in patients more than 10 years old.

Long-term results of percutaneous transluminal coronary balloon angioplasty in Kawasaki disease.

We report the long-term results of percutaneous transluminal coronary balloon angioplasty for early appearing localised stenosis of the left anterior descending artery caused by Kawasaki disease in two 2-year-olds. One patient had 50% restenosis and newly appearing aneurysm at 21-year-old, and the other had no restenosis at 16-year-old. They had no symptoms or cardiac events for 20 years. It is useful in the early localised stenosis without aneurysm.

Time Course of Coronary Artery Aneurysms in Kawasaki Disease.

OBJECTIVES: To determine the timeframe in which coronary artery aneurysms (CAAs) caused by Kawasaki disease reach their maximum diameter, the timeframe in which they regress to normal size, and the cutoff point of the diameter for CAA regression. STUDY DESIGN: We reviewed 195 CAAs of the right coronary artery, left anterior descending artery, and left coronary artery measured by 2-dimensional echocardiography ≥5 times for 1 year after Kawasaki disease in 84 patients using medical records from 1995. The maximum diameters of CAAs were investigated retrospectively. The time to CAA regression using both absolute diameter and Z score were investigated. The cutoff points of the diameter of CAA regression in the 2 classifications were identified using receiver operator characteristic curve analysis. One year after Kawasaki disease, a CAA of <3.0 mm in absolute diameter and a Z score of <2.5 were defined as CAA regression. RESULTS: The time when CAAs reached their maximum diameter ranged from 11 days to 87 days, with a median of 35 days (n = 195). The time to CAA regression ranged from 41 to 386 days, with a median of 136 days in the absolute diameter classification (n = 92); 78% of CAA regression regressed by 200 days. The cutoff point for CAA regression at one year was 5.7 mm for the absolute diameter (area under the curve, 0.887; P < .0001; n = 190) and 9.5 for the Z score (area under the curve, 0.815; P < .0001; n = 195). CONCLUSIONS: CAAs with a smaller diameter regressed earlier, and most CAAs of <6 mm regressed by 6 months after Kawasaki disease.

Changes in Coronary Aneurysm Diameters After Acute Kawasaki Disease from Infancy to Adolescence.

We clarified the changes in coronary artery diameters based on the degree of coronary artery involvement immediately after acute Kawasaki disease (KD). Two hundred sixteen coronary arteries in 85 patients after KD examined by two-dimensional echocardiography were reviewed from 1995. The maximal internal diameters were measured at 2 months, 1 year, 3 years, 10 years and 15 years after KD. The coronary arteries were divided into five groups based on the absolute diameter at 2 months, as well as six groups based on the Z score at 2 months. The maximum diameters were compared at 2 months with those during follow-up in each group. The numbers of right coronary, left anterior descending, left coronary, and left circumflex arteries were 84, 73, 55 and 4, respectively. There was a significant relationship between the maximum internal diameter at 2 months and subsequent changes in the maximum diameters after KD in the late period in both groups (p < 0.0001). The maximum diameters of coronary artery aneurysms (CAAs) ≥ 8.0 mm at 2 months did not change significantly after 1 year, however, the maximum diameter of CAAs < 8.0 mm was significantly smaller in the late period (p < 0.05). Coronary arteries without dilatation at 2 months after KD grew normally. CAAs with a maximum diameter ≥ 6.0 mm and Z score ≥ 7.5 at 2 months after KD persisted in adolescents, whereas coronary arteries with diameters < 6.0 mm and Z score < 7.5 could be within normal ranges in the late period.

Characteristics of coronary flow velocity reserve on transthoracic Doppler echocardiography in patients with a history of Kawasaki disease.

Whether the acute inflammation caused by Kawasaki disease will have an effect on the endothelial function of coronary arteries in the future is unknown. METHODS: The coronary flow velocity reserve of the left anterior descending artery was examined by transthoracic Doppler echocardiography in 189 patients (male 125, female 64) with a history of Kawasaki disease and 10 volunteers (control). Their ages ranged from 6 to 40 years (median 22 years). The patients were divided into nine groups based on the left anterior descending artery lesions. The coronary flow velocity reserve was measured by intravenous administration of adenosine triphosphate (0.15 mg/kg/minute) while fasting. The coronary flow velocity reserve was calculated as the ratio of hyperaemic to basal mean diastolic flow velocities. The respective groups were as follows: control, no coronary artery lesions (n = 39), no coronary artery lesions in the right coronary artery (n = 29), regression (n = 11), aneurysm at the bifurcation of the left coronary artery (n = 26), aneurysm of the left anterior descending artery (n = 15), localised stenosis <75% (n = 12), localised stenosis ≥75% (n = 17), segmental stenosis (n = 5) and coronary artery bypass grafting (n = 36). One-factor ANOVA followed by Tukey's test was used to compare the coronary flow velocity reserve among the groups. RESULTS: The coronary flow velocity reserve was significantly lower in the localised stenosis ≥75%, segmental stenosis and coronary artery grafting groups than in the other groups (p < 0.05). CONCLUSIONS: The endothelial function in the epicoronary artery was preserved in patients with a history of Kawasaki disease and dilated coronary artery lesions.

Cardiac Valvular Lesions due to Kawasaki Disease: A Japanese Nationwide Survey.

OBJECTIVES: To clarify the characteristics of valvular lesions after Kawasaki disease with a Japanese nationwide survey. STUDY DESIGN: Among 137 026 patients in the nationwide Japanese surveys between 2007 and 2016, 290 (0.2%) with valvular sequelae were investigated by questionnaires. RESULTS: Among the 290 patients with valvular sequelae, mitral regurgitation (MR), tricuspid regurgitation, aortic regurgitation, and pulmonary regurgitation were present 1 month after the development of Kawasaki disease in 183 (63%), 112 (39%), 39 (13%), and 49 (17%) patients, respectively. The numbers of patients with MR during the acute phase and 1 year after developing Kawasaki disease were 208 (72%) and 95 (33%), respectively. MR improved significantly during the late period (P < .0001). Although aortic regurgitation and tricuspid regurgitation also improved significantly (P < .001), pulmonary regurgitation did not change. Ruptured mitral valves chordae tendineae occurred in 6 infants by 6 months of age, within 4 months after the onset of Kawasaki disease. Three patients needed mitral valve plasty, and 1 patient died of acute heart failure. Another 4-month-old girl died of an acute myocardial infarction with MR. In the acute phase, there was a significant difference in the MR severity between the intravenous immunoglobulin-responder group and the intravenous immunoglobulin-resistant group (P < .05). CONCLUSIONS: The inflammation caused by acute Kawasaki disease affects the function of the mitral valves. Most cases of MR improve with the alleviation of inflammation. Severe MR may have decreased with the development of treatment for acute vasculitis. However, ruptured mitral valves chordae tendineae rarely occurs in infants younger than 6 months old, within 4 months after Kawasaki disease.

Cardiac Function by Magnetic Resonance Imaging in Coronary Artery Occlusions After Kawasaki Disease.

BACKGROUND: To clarify ventricular function in patients with asymptomatic coronary artery occlusion (ACAO) after Kawasaki disease (KD).Methods and Results:We enrolled 65 patients with coronary artery lesions who had undergone cardiac magnetic resonance (CMR). Median age at CMR was 29 years. CMR was performed to evaluate only the transmural extent of late gadolinium enhancement (LGE) and ejection fraction (EF). Based on the depth of LGE, it was classified into 5 groups: 0% (G0), 1-25% (G1), 26-50% (G2), 51-75% (G3), and 76-100% (G4). We investigated the relationship of the degree of LGE and EF. Further, we also evaluated the EF among 3 groups [ACAO, myocardial infarction (MI), and noncoronary artery occlusion (Non-CO)]. The grade of LGE and the LVEF (mean±SD, %) were as follows: G0 (n=24, 52.6±4.8), G1 (n=13, 50.8±4.4), G2 (n=15, 49.1±5.6), G3 (n=9, 30.9±9.1), and G4 (n=9, 27.7±6.8). LVEF in patients with G3 and G4 was significantly low (P<0.05). LVEF (%) in patients with ACAO, MI, and Non-CO were 50.5±4.8 (n=38), 33.6±10.8 (n=17), and 53.0±5.7 (n=10), respectively. LVEF in the MI group was significantly low (P<0.0001). CONCLUSIONS: LGE >50% can lead to LV dysfunction. The transmural extent of LGE in most of the study patients with ACAO was ≤50% and they had subendocardial infarction, with preserved LV function.

Insights into stent implantation for coronary artery lesions caused by Kawasaki disease.

Fifty years have passed since the first report of Kawasaki disease in 1967, and the prevalence of acute coronary syndrome in Kawasaki disease patients with coronary artery lesions exceeding 40 years old has increased. Primary coronary stent implantation is currently an acceptable method in ischaemic coronary heart disease in adults. However, it is unknown whether the stent implantation is effective or not in this population. As the clue to answer this question, I reviewed the references on Kawasaki disease patients who underwent the stent implantations between 1997 and 2019. Thirty-three patients underwent stent implantations for 34 coronary arteries. Adverse effects in the late period were found in 19 (68%) of 28 vessels with follow-up angiograms. There were complete occlusion 9, restenosis 8, and migration 2. A new aneurysm formation was found in 7 (37%) among the 19 vessels, and 6 (86%) of the 7 vessels were drug-eluting stent and 5 were found after the procedure for chronic total occlusion. The adverse effects free-rate at 1 year and 3 years were 57 and 25%, respectively. At present, the usefulness of stent implantation in the long-term results was scarce. Even if primary percutaneous coronary intervention without a stent implantation is performed for acute coronary syndrome, it can be expected to maintain the patency of the culprit lesion for several years. It is better to avoid a stent implantation as long as possible in this population. Knowing the long-term efficacy and complications of stent implantations is important for deciding the procedure.

Two females with coronary artery occlusion caused by presumed Kawasaki disease would have delivered without recognition of ischaemic heart disease.

We report two females with coronary artery occlusion caused by presumed Kawasaki disease that delivered children without any special treatment. After a 58-year-old female had ventricular tachycardia, a giant coronary artery aneurysm with calcification at the bifurcation of the left coronary artery and segmental stenosis of the right coronary artery were pointed out by CT angiography. She had an episode of sepsis when 3 years old. Further, she remembered chest pain during sleep after that episode. She had delivered twice without any complication during her 20s. Her diagnosis was undiagnosed coronary artery lesions caused by presumed Kawasaki disease and a previous myocardial infarction, and she underwent radiofrequency catheter ablation and implantable cardioverter defibrillator implantation. The other 48-year-old female was accidentally discovered to have coronary artery calcification on CT, while experiencing pneumonia. Her CT angiograms revealed a right coronary artery occlusion and coronary artery calcification at segments 1, 6, and 11. She had a history of "scarlet fever" before 12 months. Premature ventricular contractions were detected, while delivering her first child when 31 years old. However, she was not diagnosed as ischaemic heart disease and delivered twice by a vaginal delivery without any complication. Current guidelines recommend systemic anti-coagulation and anti-platelet therapy for all patients with giant aneurysms resulting from Kawasaki disease in childhood. The two women reported here were fortunate not to have had complications during pregnancy and delivery despite their severe coronary artery aneurysms, which were unrecognised clinically until later in life. They were lucky cases.

Cardiac events in Patients in their forties with Kawasaki disease and regression of coronary artery aneurysms.

Over a 50-year period from the first description of Kawasaki disease, we encountered three male patients with a history of Kawasaki disease, who had their first cardiac events in their forties. They were considered to have almost normal coronary arteries in the coronary angiograms when they were children and adolescents. They had no follow-up examinations after 20 years old. The 1st patient had an acute myocardial infarction, and the 2nd was a new appearance of coronary aneurysm and stenotic lesions with coronary artery calcification. The 3rd patient had unexpected sudden death. The interval from the onset of Kawasaki disease to the cardiac events ranged from 37 to 38 years. In the former two patients, coronary artery lesions could not be evaluated immediately after Kawasaki disease. Although the 3rd patient had bilateral medium-sized coronary artery aneurysms, his coronary aneurysms regressed 1 year after acute Kawasaki disease. The intimal thickening at a previous coronary aneurysm at the age of 19 was mild. The patients with regressed coronary aneurysms were asymptomatic for about 40 years after Kawasaki disease, prior to their cardiac events. Coronary artery calcification of the proximal portion of the major coronary arteries was a predictable marker in such patients. To prevent serious cardiac events in middle-aged adult patients, reevaluation of coronary artery lesions and restarting of anti-thrombotic therapy are needed. We must be aware that there are some differences in the clinical course and time of cardiac events between patients with giant aneurysms and those with medium aneurysms.

Magnetocardiographic recognition of abnormal depolarization and repolarization in patients with coronary artery lesions caused by Kawasaki disease.

Myocardial ischemia changes the electrophysiological properties of the myocardium, but it is difficult to detect the abnormalities of depolarization and repolarization noninvasively in patients with coronary artery disease. Depolarization and repolarization abnormalities were retrospectively investigated in 61 patients (48 males and 13 females) with coronary artery lesions (CALs) caused by Kawasaki disease (KD) from 2007 to 2014 using magnetocardiography (MCG). CAL had been diagnosed by selective coronary angiography. Current arrow maps (CAMs) were constructed during depolarization and repolarization [corrected]. The MCG findings were compared between the stenotic lesions group (SL group) and the non-stenotic lesions group (non-SL group). The incidence of MCG abnormalities was significantly higher in the SL group than in the non-SL group (p < 0.0001). The incidence of abnormal repolarization was significantly higher than that of abnormal depolarization (p < 0.0001). The number of coronary artery occlusions significantly affected the severity of abnormal repolarization (p = 0.02). Six (75%) of the patients with abnormal depolarization had a previous anteroseptal myocardial infarction. The transmural myocardial infarction affects on abnormalities of depolarization, and the non-transmural myocardial infarction might relate on abnormalities of repolarization. The myocardial electrical properties were preserved in patients except very severe coronary stenosis. MCG is possible to detect electrical myocardial abnormalities noninvasively in patients with CALs caused by KD.

Correction to: Magnetocardiographic recognition of abnormal depolarization and repolarization in patients with coronary artery lesions caused by Kawasaki disease.

In the original publication of the article, the sentence "The integral value was computed for each channel, and isointegral maps were constructed during depolarization and repolarization." was published incorrectly under the abstract section.

Ruptured mitral valves chordae tendineae around a convalescent infant with acute Kawasaki disease.

Severe valvulitis owing to acute Kawasaki disease leading to severe mitral regurgitation is a rare event in infants. Further, there is less information about underlying ruptured mitral chordae tendineae causing severe mitral regurgitation. We encountered ruptured mitral chordae tendineae in three female patients after Kawasaki disease. The age at the onset of Kawasaki disease ranged from 3 to 8 months, and detection of ruptured mitral chordae tendineae was from 24 to 90 days. Two patients had acute heart failure, and one was asymptomatic. One patient underwent mitral annuloplasty, and the others responded to medication. These ruptured mitral chordae tendineae occurred after the remission of the initial acute Kawasaki disease, in the early course and the convalescent of acute Kawasaki disease. Further, the recurrent fever was also detected in them. The ruptured mitral chordae tendineae in an infant within 6 months can be detected by systolic heart murmur around the convalescent stage of acute Kawasaki disease, although the prevalence is very low.

Cellular fraction analysis of pericardial effusion helps the diagnosis of eosinophilic myocarditis.

Eosinophilic myocarditis is rare in children, and consequently, it is difficult to diagnose eosinophilic myocarditis rapidly. We report the clinical course of acute eosinophilic myocarditis with pericarditis in two adolescent boys and their associated electrocardiograms. The two patients, 13- and 14-year-old boys, developed cardiomegaly and chest pain with vomiting. On examination by two-dimensional echocardiography, thickening of the ventricular septum and a pericardial effusion were detected. The eosinophil count had increased by the pericardial effusion. Acute eosinophilic myocarditis often complicates a moderate to severe pericardial effusion owing to acute pericarditis. A cellular fraction analysis of the pericardial effusion is easy and useful for the diagnosis of eosinophilic myocarditis. Some serial changes in the electrocardiogram occur during each stage of acute eosinophilic myocarditis. They are induced by eosinophilic granules, which are capable of inducing tissue damage and dysfunction, and those changes in the electrocardiogram resemble the changes after an acute myocardial infarction. It is important to know the characteristics of eosinophilic myocarditis in order to prevent lethal complications.

Stenotic Lesions and the Maximum Diameter of Coronary Artery Aneurysms in Kawasaki Disease.

OBJECTIVES: To determine the prevalence of subsequent stenotic lesions based on the maximum diameter of the largest coronary artery aneurysm in patients with Kawasaki disease and the threshold value of coronary artery diameter associated with risk of developing stenotic lesion. STUDY DESIGN: There were 214 patients (160 males) who had at least 1 aneurysm in a selective coronary angiogram (CAG) done <100 days after the onset of Kawasaki disease were studied. We measured the maximal coronary artery aneurysm diameter in 3 major branches in the initial CAGs. Branches were classified into 3 groups according to their maximal coronary artery aneurysm diameter: large, ≥8.0 mm; medium, ≥6.0 mm but <8.0 mm; and small, <6.0 mm. Subsequent CAGs were performed in the late follow-up period. We investigated the stenotic lesion in the follow-up CAGs, and evaluated the prevalence of stenotic lesion in each group based on body surface area (BSA) by the Kaplan-Meier method. Localized stenosis of ≥25% and complete occlusion were included as stenotic lesion in this study. We also determined the cutoff point for stenotic lesion. RESULTS: The median interval from the initial CAGs to the latest CAG was 8 years, with a maximum of 32 years. For a BSA of <0.50 m2, the 20-year prevalence of large and medium stenotic lesions was 78% (n = 62; 95% CI, 63-89) and 81% (n = 40; 95% CI, 63-89), respectively. For a BSA of ≥0.50 m2, large and medium stenotic lesions were 82% (n = 75; 95% CI, 67-91) and 40% (n = 56; 95% CI, 20-64), respectively (P < .0001). CONCLUSION: The cutoff points of the coronary artery diameter within the first 100 days after the onset of Kawasaki disease leading to a stenotic lesion in the late period, were a diameter of ≥6.1 mm with a BSA of <0.50 m2 and a diameter of ≥8.0 mm with a BSA of ≥0.50 m2. Those cutoff points would have corresponded with a Z score of at least 10 on 2-dimensional echocardiography. Careful follow-up and antithrombotic therapy should be provided to patients who meet these criteria.

Genetic background of Japanese patients with pediatric hypertrophic and restrictive cardiomyopathy.

Hypertrophic cardiomyopathy (HCM) and restrictive cardiomyopathy (RCM) present a high risk for sudden cardiac death in pediatric patients. The aim of this study was to identify disease-associated genetic variants in Japanese patients with pediatric HCM and RCM. We analyzed 67 cardiomyopathy-associated genes in 46 HCM and 7 RCM patients diagnosed before 16 years of age using a next-generation sequencing system. We found that 78% of HCM and 71% of RCM patients carried disease-associated genetic variants. Disease-associated genetic variants were identified in 80% of HCM patients with a family history and in 77% of HCM patients with no apparent family history (NFH). MYH7 and/or MYBPC3 variants comprised 76% of HCM-associated variants, whereas troponin complex-encoding genes comprised 75% of the RCM-associated variants. In addition, 91% of HCM patients with implantable cardioverter-defibrillators and infant cases had NFH, and the 88% of HCM patients carrying disease-associated genetic variants were males who carried MYH7 or MYBPC3 variants. Moreover, two disease-associated LAMP2, one DES and one FHOD3 variants, were identified in HCM patients. In this study, pediatric HCM and RCM patients were found to carry disease-associated genetic variants at a high rate. Most of the variants were in MYH7 or MYPBC3 for HCM and TNNT2 or TNNI3 for RCM.