Effect of beta-blockers and exercise restriction on the prevention of sudden cardiac death in pediatric hypertrophic cardiomyopathy

BACKGROUND

Risk assessment tools and effective prevention strategies for sudden cardiac death (SCD) in pediatric patients with hypertrophic cardiomyopathy (HCM) have not been established. This study aimed to evaluate the efficacy of beta-blockers and exercise restriction for SCD prevention in this population.

METHODS

We retrospectively reviewed the medical records of patients aged <18 years who were diagnosed with HCM at our center between January 1996 and December 2021. SCD and aborted SCD were defined as SCD equivalents. We divided patients based on whether they were prescribed beta-blockers or exercise restriction and compared the outcomes among the groups. The primary outcome was the overall survival (OS), and the secondary outcome was the cumulative SCD equivalent rate. Outcomes were analyzed using Kaplan-Meier curves and Cox proportional hazard analysis. We also compared patients according to the occurrence of SCD equivalents to identify SCD risk predictors.

RESULTS

Among the 43 included patients [mean age, 7.7 (1.6-12.1) years; 23 male individuals], SCD equivalents occurred in 13 patients over 11.2 (4.5-15.6) years of follow-up, among whom 12 were resuscitated and 1 died. The OS rate was significantly higher in the beta-blocker and exercise restriction groups than in the non-beta-blocker and non-exercise restriction groups (81.3 % vs. 19.1 %, p < 0.01 and 57.4 % vs. 12.7 %, p < 0.01, respectively). Among the 13 patients with SCD equivalents, 5 had 9 recurrent SCD equivalents. A significant difference was observed between the SCD equivalent and non-SCD equivalent groups in the history of suspected arrhythmogenic syncope (p < 0.01) in the univariable but not in the multivariable analysis.

CONCLUSIONS

Beta-blockers and exercise restriction may decrease the risk of SCD in pediatric patients with HCM and should be considered for SCD prevention in this population, particularly because predicting SCD in these patients remains challenging.

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.

Initial intravenous immunoglobulin therapy without aspirin for acute Kawasaki disease: a retrospective cohort study with a Bayesian inference

OBJECTIVE

To clarify the necessity of acetylsalicylic acid (ASA) administration combined with intravenous immunoglobulin (IVIG) therapy in the treatment of acute Kawasaki disease.

DESIGN

Retrospective cohort study.

SETTING

Multicentre.

PARTICIPANTS

This study included 735 patients with Kawasaki disease aged ≤10 years and hospitalised between 4 and 10 days of illness in eight Japanese hospitals from January 2016 to December 2020.

EXPOSURES

High-dose (HD) ASA was administered with initial IVIG to 333 patients in 6 hospitals (HD group). ASA was not administered routinely to 402 patients in the other two hospitals, and low-dose ASA was only administered when patients developed coronary artery lesions or pericardial effusion (non-HD group).

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome was the presence of coronary artery lesions, defined as a coronary artery diameter >+2.5 SD of body surface area within 1 month of onset. The secondary outcome was responsiveness to the initial IVIG therapy. Adjusted risk ratios for the outcomes were calculated using modified Poisson regression models. Bayesian analysis was conducted to estimate the posterior probability of the treatment effect of HD ASA under several prior distributions.

RESULTS

The incidence of coronary artery lesions was not significantly higher in the HD group than in the non-HD group (12/333 (3.6%) vs 15/402 (4.0%)). The proportion of non-responders to initial IVIG was similar between the two groups (HD group: 78/333 (23%); non-HD group: 83/402 (22%)). In the Bayesian analysis, considering a difference of ≤2% to be of no clinical importance, there was only a 9.3% chance of reduced risk of coronary artery lesions in the HD group compared with the non-HD group even with a strongly enthusiastic prior for HD treatment.

CONCLUSIONS

Compared with HD ASA treatment, treatment without ASA in the acute phase of Kawasaki disease was not associated with increased complications from Kawasaki disease.

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.

Thirty-year outcome in children with hypertrophic cardiomyopathy based on the type

BACKGROUND

We reviewed the long-term outcome of children with hypertrophic cardiomyopathy (HCM) based on the type.

METHODS

We reviewed the medical records of 100 patients (male 54 female 46) with HCM at our hospital between 1977 and 2015. The survival and cardiac event-free survival rates were calculated by the Kaplan-Meier method.

RESULTS

The age at the time of the diagnosis ranged from 0 to 15 years with a median of 8 years. The number of patients with Noonan syndrome and hypertrophic obstructive cardiomyopathy (HOCM), idiopathic HCM (i-HCM), and secondary HCM (s-HCM) was 13, 13, 65, and 9 respectively. A dilated phase of HCM occurred in 24 patients. Nineteen (79 %) of the 24 patients died of heart failure, and two underwent a heart transplantation. Eight (33 %) of the 24 patients had s-HCM. The median age when a dilated phase occurred was 15 years old, and the median interval from the initial diagnosis to the dilated phase was 8 years. The median time from the diagnosis of a dilated phase to death was 1.6 years. Sudden death and implantable cardioverter defibrillator implantations occurred in 6 and 11 patients at around 15 years old, respectively. The 20-year survival rates were as follows: Noonan syndrome 84 %; HOCM 82 %; i-HCM 71 %; and s-HCM 17 %. Overall, the survival rates at 10, 20, and 30 years were 83 % (95 % confidence interval 73-89), 69 % (58-78), and 63 % (50-74), respectively. The overall cardiac event-free survival rates at 10, 20, and 30 years were 57 % (47-67), 39 % (31-50), and 32 % (21-44), respectively.

CONCLUSION

The long-term outcome in children with HCM was poor, and the outcome of s-HCM was very poor. The occurrence of a dilated phase worsened the outcome in HCM patients. Sudden death and d-HCM often occurred at around 15 years old.

Coronary artery aneurysms of unknown origin in a 14-year-old girl

The case of a 14-year-old girl with acute myocardial infarction due to coronary artery aneurysms (CAAs) of unknown origin, which resembled coronary artery lesions caused by Kawasaki disease, is reported. She was transferred to our hospital due to chest pain with ST-T elevation. She had no history of Kawasaki disease. On the first admission, she was misdiagnosed with acute myocarditis. Then, 54 days later, she experienced chest pain with exertional dyspnea. Her electrocardiogram showed negative T waves in the chest leads. A CAA of the left coronary artery was suspected on two-dimensional echocardiography. Coronary angiograms showed 90% stenosis and multiple CAAs of the left anterior descending artery and the bifurcation of the left coronary artery. Both the right coronary artery and left circumflex artery were occluded. A left ventriculogram showed dyskinesis and an aneurysm at the apex. She underwent triple-vessel coronary artery bypass grafting, and her symptoms improved. In addition, an intracranial aneurysm was also found on cerebral angiography. There were no specific laboratory findings other than SS-A antibodies. It was suspected that the weakness of the vessels was related to the disease. It may have been a different disease that was never previously detected, but her CAAs were Kawasaki-like CAAs. <Learning objective: A timely precise diagnosis of acute myocardial infarction is unlikely to be made in children because they are rare. The present patient was initially misdiagnosed as having acute myocarditis, because the coronary arteries could not be detected by two-dimensional echocardiography. Either computed tomographic angiography or magnetic resonance angiography is recommended in patients with ST-T abnormalities on the electrocardiogram if it is difficult to identify the coronary arteries. In this case, the patient had a rare coronary artery disease in which the cause of the coronary artery aneurysms was unknown.

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.

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.

Bilateral internal thoracic artery grafting in children under 5 years of age with Kawasaki disease: a case series

Background

Although persistent coronary artery aneurysm of Kawasaki disease (KD) is rare, some patients develop a life-threatening myocardial infarction. In paediatric coronary artery bypass surgery (PCABS), the internal thoracic artery (ITA) graft is a reliable graft with favourable coronary outcomes. However, few studies have reported the outcomes and technical considerations of PCABS using bilateral ITAs in small children who have multivessel disease.

Case summary

We present the cases of three children under 5 years of age who underwent PCABS utilizing bilateral ITAs. All three patients had known bilateral giant coronary aneurysms associated with KD. Paediatric coronary artery bypass surgery was indicated after confirming multiple coronary lesions with myocardial ischaemia. One child underwent emergency PCABS because of circulatory collapse. The arterial anastomoses were performed under cardioplegic arrest. The left ITA was anastomosed to the left anterior descending artery (LAD) or the circumflex artery. The right ITA was anastomosed to the right coronary artery or the LAD. Post-operative coronary angiography revealed patent bilateral ITA grafts with an excellent run-off in all patients, and none of them have suffered any subsequent coronary event.

Discussion

Bilateral ITA grafting is a feasible procedure with favourable coronary outcomes for treating small children with multivessel disease, even in the setting of circulatory collapse.

Etiology of atrial fibrillation in patients with complex congenital heart disease - for a better treatment strategy

BACKGROUND

The demographics of patients with congenital heart disease (CHD) and atrial fibrillation (AF) differ significantly from the general population. The etiology and treatment strategy for AF in CHD patients have been investigated but are to date inconclusive.

METHODS

To determine the etiology of AF in CHD and to seek a better treatment strategy, we retrospectively evaluated the atrial overload in 42 complex CHD cases with normal atrial arrangements and AF (age 25; range, 9-66 years) and the impact of a reduction in the atrial overload on the atrial rhythm.

RESULTS

Cardiac defect diagnoses varied, with 17% of the patients having a persistent left superior vena cava (PLSVC). In regard to the volume overload, the frequencies of an overload in the right atrium (RA), left atrium (LA), or both, were 50 %, 23%, and 10%, respectively (p = 0.015). Other sustained supraventricular tachycardias were observed in 29 patients (69%) before and after the onset of AF. Among these 29 patients, 26 had intra-atrial reentrant tachycardia. Fifteen patients (36%), 10 of whom had chronic AF, died during the follow-up including 3 with arrhythmias and 10 because of heart failure. Fourteen (33%) patients had no AF at the last follow-up due to medical interventions, 8 of which underwent solely an RA-sided catheter ablation and/or surgical RA overload reduction.

CONCLUSIONS

AF in complex CHD with a normal atrial arrangement correlates with a higher RA-sided overload than an LA-sided and exhibits a high incidence of PLSVCs, high comorbidity of intra-atrial reentrant tachycardias, and high mortality rate. In a substantial number of patients, RA-sided interventions were effective in controlling AF. To effectively manage AF in complex CHD it is essential to understand each individual's hemodynamics and consider hemodynamic interventions.

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.

Electrocardiographic changes and long-term prognosis of children diagnosed with hypertrophic cardiomyopathy by the school screening program for heart disease in Japan

BACKGROUND

In Japan, the school screening program for heart disease (SS) has been performed since 1973. However, little has been reported on the electrocardiogram (ECG) changes and long-term prognosis in patients with hypertrophic cardiomyopathy (HCM) detected by the SS.

METHODS

All 44 consecutive pediatric HCM patients (10.1 ± 3.0 years old), who had been originally consulted by the SS before the diagnosis of HCM from April 1981 to April 2017, were reviewed retrospectively.

RESULTS

At the SS, all patients showed mild or no symptoms. All patients showed ECG abnormalities, and 75 % had a high proposed ECG risk score (≧6). However, 30 % of them had no echocardiogram finding of myocardial hypertrophy. During the follow-up period (14.8 ± 10.0 years), life-threatening events (LTE) occurred in 11 (25 %) patients, and the first LTE occurred during exercise in 8 (18 %). The estimated LTE and heart failure death-free survival rate at 10 years was 64.9 %. The LTE-free survival rate was lower in patients without than in those with myocardial hypertrophy at the SS.

CONCLUSIONS

The SS was useful in detecting patients with HCM with mild or no symptoms at the early stage. However, our study indicated that early detection of HCM is not associated with improvement in the prognosis of the patients. Further studies are needed.

Significance of Coronary Revascularization for Coronary-Artery Obstructive Lesions Due to Kawasaki Disease

As an acquired ischemic heart disease in childhood, coronary-artery disease caused by Kawasaki disease (KD) has been known worldwide since the mid-1970s. KD patients who develop coronary-artery obstructive disease often need revascularization some time in their life. Coronary-artery revascularization for KD coronary lesions can be done with the surgical coronary-artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) procedures. However, the characteristics of coronary-arterial lesions caused by KD significantly differ from atherosclerotic coronary disease in adults. Therefore, it is much more difficult to determine the optimal time and selection of a coronary-artery revascularization procedure for KD sequelae. CABG using the internal thoracic artery has been accepted as a very useful and beneficial procedure since the mid-1980s, even in small children. Although the use of PCI in the late period can be effective in some adolescent and adult patients, the small vessel size and severe coronary-artery calcification are often limiting factors for its use in children. Therefore, CABG is a better approach for severe leftanterior descending artery and multiple-vessel disease in children and adolescents with KD coronary sequelae. Good coronary revascularization can improve the long-term outcomes of patients with severe KD complications.

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.

The TNNI3 Arg192His mutation in a 13-year-old girl with left ventricular noncompaction

Left ventricular noncompaction (LVNC) is a distinct cardiomyopathy that is morphologically characterized by a two-layered myocardium, numerous prominent trabeculations, and deep intertrabecular recesses communicating with the left ventricular cavity. We present a case report regarding the identification of a new mutation in TNNI3 in a patient with LVNC using next-generation sequencing. A 13-year-old girl who had no family history of cardiac disease was hospitalized with dyspnea after exercise and electrocardiographic abnormalities during a school screening. Based on her clinical features, she was diagnosed with LVNC. Via genetic analysis, a TNNI3 heterozygous missense variant was identified in the proband. Although mutations in TNNI3 have been reported in patients with hypertrophic cardiomyopathy and restrictive cardiomyopathy, this is the first report of a mutation in this gene in a patient with LVNC. <Learning objective: We identified a variant in TNNI3 in a patient with isolated left ventricular noncompaction using next-generation sequencing (NGS). Mutations in TNNI3 have been reported in patients with hypertrophic cardiomyopathy and restrictive cardiomyopathy. The use of NGS also results in the identification of multiple genetic variants of unknown significance to the investigated disease.>.

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.

Coronary Artery Ectasia Predicts Future Cardiac Events in Patients With Acute Myocardial Infarction

Objective—

Coronary artery ectasia (CAE) is an infrequently observed vascular phenotype characterized by abnormal vessel dilatation and disturbed coronary flow, which potentially promote thrombogenicity and inflammatory reactions. However, whether or not CAE influences cardiovascular outcomes remains unknown.

Approach and Results—

We investigated major adverse cardiac events (MACE; defined as cardiac death and nonfatal myocardial infarction [MI]) in 1698 patients with acute MI. The occurrence of MACE was compared in patients with and without CAE. CAE was identified in 3.0% of study subjects. During the 49-month observation period, CAE was associated with 3.25-, 2.71-, and 4.92-fold greater likelihoods of experiencing MACE (95% confidence interval [CI], 1.88–5.66; P <0.001), cardiac death (95% CI, 1.37–5.37; P =0.004), and nonfatal MI (95% CI, 2.20–11.0; P <0.001), respectively. These cardiac risks of CAE were consistently observed in a multivariate Cox proportional hazards model (MACE: hazard ratio, 4.94; 95% CI, 2.36–10.4; P <0.001) and in a propensity score–matched cohort (MACE: hazard ratio, 8.98; 95% CI, 1.14–71.0; P =0.03). Despite having a higher risk of CAE-related cardiac events, patients with CAE receiving anticoagulation therapy who achieved an optimal percent time in target therapeutic range, defined as ≥60%, did not experience the occurrence of MACE ( P =0.03 versus patients with percent time in target therapeutic range <60% or without anticoagulation therapy).

Conclusions—

The presence of CAE predicted future cardiac events in patients with acute MI. Our findings suggest that acute MI patients with CAE are a high-risk subset who might benefit from a pharmacological approach to controlling the coagulation cascade.

Role of imaging studies in Kawasaki disease

Kawasaki disease is a medium vessel vasculitis which may be associated with coronary artery abnormalities. Recognition of these abnormalities depends upon various imaging modalities. While two-dimensional echocardiography remains the first line modality to identify coronary artery abnormalities, it is subject to several fallacies and is operator dependent. Computed tomography coronary angiography is rapidly emerging as a useful imaging modality for better characterization of dilatations, ectasia and aneurysms in the mid- and distal segments of coronary arteries. It provides precise details in terms of aneurysm size and morphology. In this review we here described the importance of computed tomography coronary angiography and have also given a brief description of magnetic resonance coronary angiography.

Nationwide Survey of Patients With Giant Coronary Aneurysm Secondary to Kawasaki Disease 1999-2010 in Japan

BACKGROUND

Giant coronary aneurysm is the most severe sequela in Kawasaki disease, occurring in approximately 0.2% of patients in Japan. Regression is rare, while myocardial infarction (MI) and sudden death are relatively common. Herein, we reviewed patients with giant coronary aneurysm in a 10-year period.Methods and Results:A nationwide questionnaire survey was conducted based on a national epidemiological database from 1999 to 2010. We identified 355 giant coronary aneurysm patients, of whom 209 were analyzed. The 5- and 10-year total cardiac event-free rates were 0.72 and 0.68, respectively. Twelve patients died, and MI was observed in 32 patients (18.1%). Five and 6 deaths were due to coronary rupture and MI, respectively. All ruptures occurred within 1 month of onset, while most MI occurred within 18 months. There was no death beyond 2 years. Aneurysm size was significantly related to the occurrence of MI in both the right and left coronary arteries. At the time of writing, 55% of patients had no exercise limitations. And including patients who cannot perform strenuous exercises, 81% of patients were leading ordinary lives.

CONCLUSIONS

Severe cardiac events are likely to occur within 2 years from onset of Kawasaki disease, while no deaths occurred beyond this time. Hence, careful monitoring is needed especially for the first 2 years. Most patients with giant coronary aneurysms can lead ordinary lives with appropriate management.

Distribution of Kawasaki Disease Coronary Artery Aneurysms and the Relationship to Coronary Artery Diameter

We investigated how the diameter of coronary artery aneurysm (CAA) relates to the distribution immediately after Kawasaki disease (KD). Two hundred and four pts (155 males and 49 females) who had undergone selective coronary angiography (CAGs) less than 100 days after the onset of KD were studied. We measured the maximum diameter of each artery segment in the initial CAGs. We analyzed the relationship between the maximum diameters and the distribution of CAA. We divided the patients into four groups based on the maximum CAA diameter in each patient (large(L) ≥8 mm, medium(M) ≥6 and <8 mm, small(S) ≥4 and <6 mm, very small(VS) <4 mm) and counted the affected segments. There were 87, 61, 36, and 20 patients in groups L, M, S, VS, respectively. The number of segments with CAA in each group was L 6 ± 2, M 4 ± 2, S 2 ± 2, VS 2 ± 1. The number of affected segments in L was significantly more than M, and a large value for L indicated that involvement was significantly more likely to be bilateral. The larger the maximum diameter of CAA, the more extensive disease involvement and the more likely to be bilateral. A large maximum CAA can also indicate coronary involvement in the longitudinal directions. It is an important charcteristic in distribution of CAA caused by KD vasculitis.

Mid-Term Follow-up of School-Aged Children With Borderline Long QT Interval

BACKGROUND

There are no definitive diagnostic criteria or follow-up strategies for long QT syndrome (LQTS) in children with a borderline long QT interval (b-LQT).Methods and Results:We retrospectively evaluated the clinical course, genetic testing results, corrected QT interval (QTc), and LQTS score of 59 school-aged children (5-18 years old) with a b-LQT (400≤QTc<500 ms). Syncope, but neither aborted cardiac arrest nor sudden cardiac death, occurred in 2 patients during the follow-up (6±3.4 years) with LQTS scores ≥4.5 points. The genetic testing results were positive in 92%, 57%, and 67% of patients with high, intermediate, and low probabilities of LQTS, respectively. The maximum and mean QTc during the follow-up significantly differed among the categories with a probability of LQTS, but not the minimum QTc. However, the QTc at rest and at the recovery point after exercise stress testing dramatically changed at the last follow-up. Consequently, the probability of LQTS changed in half of the patients.

CONCLUSIONS

The LQTS score is a reasonable indicator for evaluating school-aged children with a b-LQT, and patients with a low LQTS score appear to be at low risk for cardiac events. However, the LQTS score can change during follow-up. Therefore, when there is doubt or concern for patients with a b-LQT, it is preferable to continue following them. Guidelines on follow-up strategies are desired for b-LQT.

Late Wall Thickening and Calcification in Patients After Kawasaki Disease

OBJECTIVES

To evaluate the relationship between the initial diameters of the coronary arteries immediately after the onset of Kawasaki disease (KD) and late increased coronary wall thickening/coronary artery calcification (CAC).

STUDY DESIGN

Sixty-five patients (50 males and 15 females) who had undergone selective coronary angiography (CAG) <100 days after the onset of KD were studied late in disease by dual-source computed tomography (DSCT). The maximum diameters of each segment were measured in the initial CAGs, and the relationship between the maximum diameters and the appearance of increased wall thickening/CAC was analyzed. The study cohort was divided into 2 groups: the branches group (BG) and bifurcation at the left coronary artery (LCA) group. The cutoff point of acute coronary artery dilatation for increased wall thickening/CAC was calculated for each group. Risk factors for the appearance of CAC in each group were investigated, as was the sex difference related to the prevalence of CAC in coronary artery lesions (CALs) of the initial CAGs.

RESULTS

The cutoff points of acute coronary dilatation for increased wall thickening were 4.8 mm in the BG (n = 344; area under the curve [AUC], 0.89; P < .001) and 5.3 mm in the LCA group (n = 65; AUC, 0.87; P < .001). The interval from the onset of KD (P < .0001) and sex (P = .0084) were also related to the appearance of CAC in the BG.

CONCLUSION

Acute coronary dilatation of exceeding ~5.0 mm can lead to late abnormalities of the coronary artery wall. The prevalence of CAC increases with age. There was a sex-based difference in the late incidence of CAC in the CALs.

Early Single Institutional Experience of Berlin Heart EXCOR® Pediatric Ventricular Assist Device in Japan

BACKGROUND

Since August 2015, the pediatric ventricular assist device (VAD), Berlin Heart EXCOR^®, has been accepted for use in Japan.Methods and Results:Between August 2015 and July 2016, 4 pediatric patients with endstage heart failure underwent LVAD implantation with the EXCOR^®device. The median age and body weight at operation were 8 months and 4.8 kg. During a median follow-up of 7.3 months (range, 5.0-10.3), all patients survived. Two patients went on to heart transplantation and the remaining 2 are on a waiting list with stable hemodynamics.

CONCLUSIONS

The early outcomes of the Berlin Heart EXCOR^®pediatric VAD were satisfactory. (Circ J 2016; 80: 2552-2554).

Usefulness of Percutaneous Transluminal Coronary Balloon Angioplasty for the Left Coronary Artery Stenosis 10 Years More Than After Arterial Switch Operation

Proximal stenosis adjacent to the orifice of one or both coronary arteries may occur after the arterial switch operation (ASO) for d-transposition of the great arteries (d-TGA). Coronary artery stenosis (CAS) often progresses within the first 6 months postoperatively and may result in myocardial ischemia and infarction. Although percutaneous transluminal coronary balloon angioplasty (PCBA) for CAS within 15 months after ASO for d-TGA has been reported, there is no report of PCBA for CAS in the late period after ASO. We present the results of PCBA for CAS of the left coronary artery performed more than 10 years after ASO in an 11-year-old boy and a 14-year-old boy without complication. The stenosis degree improved in both patients from 81 to 45 and 80 to 54 %, respectively. Restenosis did not occur, and the stenosis degree improved to about 25 % late after PCBA. Although the initial effect of PCBA may not be dramatic, it can improve late after PCBA. It was considered that the optimal balloon-reference vessel ratio was about 1.0, to obtain the minimal effective lumen diameter. PCBA for CAS even if performed many years after ASO is feasible without complication. PCBA can also provide delayed improvement late after the procedure.

Characteristics and Fate of Systemic Artery Aneurysm after Kawasaki Disease

OBJECTIVE

To determine the long-term outcome of systemic artery aneurysms (SAAs) after Kawasaki disease (KD).

STUDY DESIGN

We investigated the characteristics and the fate of SAAs in 20 patients using medical records and angiograms. The age of onset of KD ranged from 1 month to 20 months. The interval from the onset of KD to the latest angiogram ranged from 16 months to 24 years. The regression rate of peripheral artery aneurysm and the frequency of stenotic lesions were analyzed by the Kaplan-Meier method in 11 patients who had undergone initial angiography within 4 months.

RESULTS

The mean duration of fever was 24 ± 12 days. All 20 patients had at least 1 symmetric pair of aneurysms in bilateral peripheral arteries, and 16 patients had multiple SAAs. The distributions of SAAs was as follows: brachial artery, 30; common iliac artery, 20; internal iliac artery, 21; abdominal aortic aneurysm, 7; and others, 29. The frequencies of regression of SAA and of the occurrence of stenotic lesions at 20 years after the onset of KD were 51% and 25%, respectively (n = 42). The diameter of all SAAs in the acute phase leading to stenotic lesions in the late period was >10 mm.

CONCLUSION

SAAs occurred symmetrically and were multiple in younger infants and those with severe acute vasculitis. The fate of SAAs resembles that of coronary artery aneurysms, and depends on the diameter during the acute phase. Larger SAAs can lead to stenotic lesions in the late period.

Active cardiac sarcoidosis in a patient with adult-onset Kawasaki disease

Adult-onset Kawasaki disease is a rare condition. Cardiac sarcoidosis is an uncommon cardiomyopathy which is characterized by progressive cardiac dysfunction, and abnormality on electrocardiography and morphological aberration of the heart. We report a first case of a combination of these rare conditions. The patient was initially diagnosed with Kawasaki disease based on the coronary artery aneurysms and a past medical history at the age of 20 years which was typical of Kawasaki disease. Decades later, he developed progressive cardiac dysfunction and a sudden-onset atrioventricular block. Laboratory and imaging results revealed severe myocardial damage and inflammation which were unexplainable by coronary artery ischemia. We diagnosed him with cardiac sarcoidosis based on a Japanese guideline to diagnose cardiac sarcoidosis. A cardiac resynchronization therapy defibrillator was implanted and he received oral steroid therapy. This rare combination of adult-onset Kawasaki disease and cardiac sarcoidosis may suggest the causative association of these conditions. <Learning objective: This is the first report of a rare combination of adult-onset Kawasaki disease and cardiac sarcoidosis. Kawasaki disease is not just a disease of children. Physicians should include Kawasaki disease in the list of differentials for unknown fever or eruptions. In patients with progressive heart failure and atrioventricular block, the possibility of cardiac sarcoidosis should be examined using various imaging modalities even if they had a known cause of cardiac dysfunction.>.

[Management for pregnancy and delivery in patients with a history of Kawasaki disease]

We report the results of pregnancy and delivery in patients with coronary artery lesions caused by Kawasaki disease. The mode of delivery should be primarily determined by obstetrical considerations, rather than the coronary arterial lesions caused by Kawasaki disease. An assisted second stage of labor using epidural anesthesia is recommended in patients with a low left ventricular ejection fraction and significant localized stenosis of a coronary artery. However, if the patients are symptomatic or they have ischemic sign, Caesarean section should be recommended based on their general condition. A holter electrocardiogram at the third trimester is useful for decision of the mode of delivery. Aspirin at low doses is considered to be safe during pregnancy and delivery.

Emergency coronary artery bypass grafting for cardiogenic shock due to left main coronary artery obstruction caused by Kawasaki disease in a 4-year-old boy

We describe the case of a 4-year-old boy whose clinical course after Kawasaki disease resulted in coronary artery bypass grafting (CABG) due to acute myocardial infarction (AMI) causing cardiogenic shock. He had developed an ischemic cardiomyopathy due to severe localized stenosis of the left main coronary artery (LCA) and went into cardiogenic shock due to AMI on the day before a scheduled operation. He underwent successful emergency CABG within 4 h of MI. Postoperatively his neurological status was intact. This is the first report of a successful emergency CABG in a small child with cardiogenic shock due to LCA occlusion. CABG should be undertaken in small patients when appropriate indications exist, if bodyweight is >10 kg.

A survey of the 3-decade outcome for patients with giant aneurysms caused by Kawasaki disease

BACKGROUND

Our purpose was to determine the outcome in patients with a more-than-20-year history of giant coronary aneurysms (GAs) caused by Kawasaki disease (KD).

METHODS

Between 2010 and 2011, the incidence and outcome of cardiac events (CEs) in patients with GA was surveyed by questionnaire by the Kinki area Society of KD research. Death, acute myocardial infarction (AMI), coronary artery bypass grafting (CABG), percutaneous coronary catheter intervention, syncope, and ventricular tachycardia were considered as CEs. Survival rate and CE-free rate were analyzed by the Kaplan-Meier method.

RESULTS

We enrolled 245 patients (187 were male, 58 were female), 141 with bilateral GA and 104 with unilateral GA. The interval between the onset of acute KD to the time of survey ranged from 0.2 to 51 years, and the median was 20 years. Death, AMI, and CABG occurred in 15 (6%), 57 (23%), and 90 patients (37%), respectively. The CE-free rate and the survival rate at 30 years after KD were 36% (95% CI 28-45) and 90% (95% CI 84-94), respectively. The 30-year survival rate for bilateral GA was 87% (95% CI 78-93), and for unilateral GA, it was 96% (95% CI 85-96; hazard ratio 4.60, 95% CI 1.27-29.4, P = .027). The 30-year survival rate in patients with AMI was 49% (95% CI 27-71), and the 25-year survival rate in patients undergoing CABG was 92% (95% CI 81-98).

CONCLUSIONS

The outcome differed significantly between bilateral GA and unilateral GA. The results focus attention on the need to preserve myocardial perfusion, especially in high-risk patients with bilateral GA. An understanding of the optimal CABG would be useful in bilateral GA.

Follow-up in a patient with previous coronary artery bypass grafting with clipping for moderate stenosis of the native artery due to Kawasaki disease

We report the beneficial outcome of coronary artery bypass grafting (CABG) with aneurysm clipping for Kawasaki disease (KD)-related moderate stenosis of the native coronary artery. A 13-year-old boy developed 90% stenosis of the left anterior descending artery (LAD) and an aneurysm with 50% stenosis of the right coronary artery (RCA) seven years after KD. We grafted the RCA with the right internal thoracic artery (RITA) and clipped the proximal RCA, in addition to conventional grafting of the LAD with the left internal thoracic artery, because we were concerned that competition in flow between the native RCA and the graft might lead to graft occlusion. Significant ischemic change developing during the operation was not detected. Postoperative coronary angiograms showed complete occlusion of the proximal RCA and LAD and good bilateral ITA graft flow. A postoperative electrocardiogram revealed an abnormal Q wave in lead III. No perfusion defects were detected in ^99mTc myocardial perfusion imaging. He stopped warfarin immediately after his operation, and aspirin one year later. He has been in good condition for 4 years after CABG. This report demonstrates, one of the graft procedures for moderate coronary stenosis, although the indication is limited. <Learning objective: When patients requiring at least one graft for severe stenosis and associated myocardial ischemia have moderate stenosis in another vessel, to graft or not to graft the second vessel, is a most difficult decision with its potential influence on future mortality and morbidity. We decided in favor of grafting with clipping the native artery for the moderate stenosis to avoid occlusion of the graft due to competition with the native flow. Complete coronary revascularization by coronary artery bypass grafting might make it safe to discontinue long-term anticoagulant therapy.>.

Haemodynamic characteristics before and after the onset of protein losing enteropathy in patients after the Fontan operation

OBJECTIVES

Determinant risk factors for developing protein losing enteropathy (PLE), including haemodynamics, remain unclear in patients after the Fontan operation.

METHODS

Our purpose was to characterize the serial PLE haemodynamics before and after the onset and to determine the risk factors based on the cardiac catheterization-based analysis.

RESULTS

Of 354 Fontan survivors who had undergone postoperative cardiac catheterizations, we experienced 26 PLE patients during the follow-up. Non-left ventricular morphology systemic ventricle, functional one-lung pulmonary circulation and an early postoperative high central venous pressure (CVP) were associated with the PLE onset and the high CVP (odds ratio (OR) = 1.19 per 1 mmHg, 95% confidence interval (CI) 1.04-1.37, especially ≥12 mmHg, OR = 3.09, 95% CI 1.25-7.64, P < 0.05 for both) and one-lung pulmonary circulation (OR = 10.0-10.5, P < 0.001) independently predicted the onset. At the time of the PLE onset, a Fontan route stenosis/obstruction, arrhythmias, ventricular dysfunction/heart failure and pulmonary arterio-venous fistulae were demonstrated in 10 (38%), 8 (31%), 4 (15%) and 3 (12%) patients, respectively. When compared with 56 excellent Fontan survivors, the high CVP, ventricular end-diastolic pressure, and pulmonary artery resistance, and the low arterial oxygen saturation, systemic artery pressure, and ventricular ejection fraction characterized the pre-PLE Fontan haemodynamics (P < 0.05-0.0001). However, the following intensive treatments reduced the CVP, systemic artery pressure and cardiac output (P < 0.05-0.01), resulting in haemodynamics no different from those of the excellent survivors, except for the low systemic pressure (P < 0.0001).

CONCLUSIONS

The pre-PLE haemodynamics was characterized by several impaired haemodynamics, while those after PLE only by a low systemic pressure. A high early postoperative CVP was the only haemodynamic predictor for a new onset of PLE. Strict selective criteria for the operation and strategies to eliminate CVP-raising factors are mandatory to prevent a new onset of PLE.