Characterization of Influenza A(H1N1)pdm09 Viruses Isolated in the 2018-2019 and 2019-2020 Influenza Seasons in Japan

The influenza A(H1N1)pdm09 virus that emerged in 2009 causes seasonal epidemic worldwide. The virus acquired several amino acid substitutions that were responsible for antigenic drift until the 2018-2019 influenza season. Viruses possessing mutations in the NA and PA proteins that cause reduced susceptibility to NA inhibitors and baloxavir marboxil, respectively, have been detected after antiviral treatment, albeit infrequently. Here, we analyzed HA, NA, and PA sequences derived from A(H1N1)pdm09 viruses that were isolated during the 2018-2019 and 2019-2020 influenza seasons in Japan. We found that A(H1N1)pdm09 viruses possessing the D187A and Q189E substitutions in HA emerged and dominated during the 2019-2020 season; these substitutions in the antigenic site Sb, a high potency neutralizing antibody-eliciting site for humans, changed the antigenicity of A(H1N1)pdm09 viruses. Furthermore, we found that isolates possessing the N156K substitution, which was predicted to affect the antigenicity of A(H1N1)pdm09 virus at the laboratory level, were detected at a frequency of 1.0% in the 2018-2019 season but 10.1% in the 2019-2020 season. These findings indicate that two kinds of antigenically drifted viruses-N156K and D187A/Q189E viruses-co-circulated during the 2019-2020 influenza season in Japan.

Electrocardiographic Diagnosis of Hypertrophic Cardiomyopathy in the Pre- and Post-Diagnostic Phases in Children and Adolescents

BACKGROUND

The usefulness of electrocardiographic (ECG) voltage criteria for diagnosing hypertrophic cardiomyopathy (HCM) in pediatric patients is poorly defined.Methods and Results:ECGs at the 1st grade (mean [±SD] age 6.6±0.3 years) were available for 11 patients diagnosed with HCM at around the 7th grade (13.2±0.3 years). ECGs were available for another 64 patients diagnosed with HCM in the 1st (n=15), 7th (n=32), and 10th (n=17) grades. Fifty-one voltage criteria were developed by grade and sex using 62,841 ECGs from the general population. Voltage criteria were set at the 99.95th percentile (1/2,000) point based on the estimated prevalence of childhood HCM (2.9 per 100,000 [1/34,483]) to decrease false negatives. Conventional criteria were from guidelines for school-aged children in Japan. Of 11 patients before diagnosis, 2 satisfied conventional criteria in 1st grade; 5 (56%) of the remaining 9 patients fulfilled 2 voltage criteria (R wave in limb-lead I [RI]+S wave in lead V3 [SV3] and R wave in lead V3 [RV3]+SV3). Robustness analysis for sensitivity showed RV3+SV3 was superior to RI+SV3. For all patients after diagnosis, RI+SV4 was the main candidate. However, conventional criteria were more useful than voltage criteria.

CONCLUSIONS

Early HCM prediction was possible using RV3+SV3 in >50% of patients in 1st grade. Voltage criteria may help diagnose prediagnostic or early HCM, and prevent tragic accidents, although further prospective studies are required.

Antigenic variants of influenza B viruses isolated in Japan during the 2017-2018 and 2018-2019 influenza seasons

Background

Here, we genetically and antigenically analyzed influenza B viruses (IBVs) isolated in Japan during the 2017‐2018 and 2018‐2019 influenza seasons.

Methods

A total of 68 IBVs (61 B/Yamagata/16/88‐like [B/Yamagata]‐lineage and 7 B/Victoria/2/87‐like [B/Victoria]‐lineage) were antigenically and genetically characterized by using hemagglutination inhibition (HI) assays and phylogenetic analysis, respectively. The susceptibility of IBVs to neuraminidase (NA) inhibitors was assessed by using a fluorescence‐based NA inhibition assay.

Results

All 61 B/Yamagata‐lineage isolates were genetically closely related to B/Phuket/3073/2013, the vaccine strain for these two seasons. Eleven B/Yamagata‐lineage isolates tested were antigenically similar to B/Phuket/3073/2013 by the HI test. Seven B/Victoria‐lineage isolates were genetically closely related to B/Texas/02/2013, the WHO‐recommended vaccine strain for the 2017‐2018 season; however, they were antigenically distinct from B/Texas/02/2013 with an eightfold or 16‐fold difference in HI titer. Of these 7 isolates, 4 possessed a two‐amino‐acid deletion at positions 162 and 163 in hemagglutinin (HA) and the other 3 had a three‐amino‐acid deletion at positions 162‐164 in HA. Importantly, the variants with the three‐amino‐acid deletion appeared to be antigenically different from the B/Colorado/06/2017 virus with the two‐amino‐acid deletion, the vaccine strain for the 2018‐2019 season with a fourfold or eightfold difference in HI titer. One B/Yamagata‐lineage isolate carrying a G407S mutation in its NA showed a marked reduction in susceptibility to zanamivir, peramivir, and laninamivir.

Conclusions

These results highlight the need for continued monitoring for the prevalence of the antigenic variant with the three‐amino‐acid deletion and the variant with reduced NA inhibitor susceptibility.

Influenza A variants with reduced susceptibility to baloxavir isolated from Japanese patients are fit and transmit through respiratory droplets

Here we report the isolation of the influenza A/H1N1 2009 pandemic (A/H1N1pdm) and A/H3N2 viruses carrying an I38T mutation in the polymerase acidic protein-a mutation that confers reduced susceptibility to baloxavir marboxil-from patients before and after treatment with baloxavir marboxil in Japan. These variants showed replicative abilities and pathogenicity that is similar to those of wild-type isolates in hamsters; they also transmitted efficiently between ferrets by respiratory droplets.

P3468Tentative criteria of a combined RV3+SV3 voltage for early diagnosis of pediatric patients with hypertrophic cardiomyopathy

Background

A high voltage in midprecordial leads, termed the Katz-Wachtel sign, is a surrogate marker of left- or bi-ventricular hypertrophy. Asymmetrical interventricular hypertrophy is a characteristic feature of hypertrophic cardiomyopathy (HCM). In Japan, a school-based electrocardiographic (ECG) screening program was developed for all 1st, 7th, and 10th graders. Our hypothesis is that a combined voltage of RV3+SV3 {V3(R+S)} is a marker to screen pediatric HCM.

Purpose

[1] To develop V3(R+S) voltage criteria in 1st, 7th, and 10th graders at the screening program and [2] to determine whether the criteria are useful for the early diagnosis of HCM.

Methods

[1] Overall, 48,401 digitally stored ECGs from 16,773 1st graders (6-year-olds), 18,126 7th graders (12-year-olds), and 13,502 10th graders (15-year-olds) were obtained after excluding ECGs of subjects with underlying diseases, arrhythmias, and ST/T changes. The prevalence of HCM in children is estimated at 2.9 per 100,000 (1/34,000). The screening points were assumed to be between 1/2,000 and 1/5,000 to exclude the possibility of false negatives. [2] In 12 HCM patients (males/females=10/2) who were diagnosed after 12 years of age (one case was diagnosed at 9 years of age), the ECGs at the screening program of their first grade (at 6 years of age) were retrospectively examined.

Results

[1] The V3(R+S) criteria were 6.0 mV, 6.0 mV, and 5.5 mV for 1st, 7th, and 10th grader males, and 5.0 mV, 4.5 mV, and 4.0 mV for 1st, 7th, and 10th grade females, respectively. The number of subjects (and prevalence in parentheses) selected by the criteria were 2 (1/4175), 3 (1/2981), and 1 (1/6477) for 1st, 7th, and 10th grade males, and 2 (1/4212), 3 (1/3061), and 1 (1/3513) for 1st, 7th, and 10th grade females, respectively. [2] Four of 12 cases fulfilled the criteria. Of these, one suddenly died at 18 years of age, one experienced out-of-hospital cardiac arrest at 16 years of age, and one already had an interventricular thickness of 19 mm at 12 years of age.

Conclusions

These tentative V3(R+S) voltage criteria may be useful for the early diagnosis of pediatric HCM patients, particularly severe patients. The children and adolescents who were screened can be followed at 2–3-year intervals with ECGs and echocardiography. Early diagnosis and intervention including lifestyle modification and medication may prevent them expiring from out-of-hospital cardiac arrest or sudden death. Finally, the criteria should be validated in clinical settings.

Acknowledgement/Funding

A Health and Labour Sciences Grant from the Ministry of Health, Labour and Welfare of Japan (H27-019)

Standard Values and Characteristics of Electrocardiographic Findings in Children and Adolescents

BACKGROUND

Reference values and the characteristics of the electrocardiographic (ECG) findings using a large number of subjects are lacking for children and adolescents.Methods and Results:A total of 56,753 digitally stored ECGs of participants in a school-based ECG screening system were obtained between 2006 and 2009 in Kagoshima, Japan. Each ECG was manually reviewed by 2 pediatric cardiologists and only ECGs with sinus rhythm were included. A final total of 48,401 ECGs from 16,773 1st (6 years old, 50% girls), 18,126 7th (12 years old, 51% girls), and 13,502 10th graders (15 years old, 52% girls) were selected. ECG variables showed differences in age and sex. However, the effects of age and sex on ECG variables such as the PQ interval, QRS voltage, and STJ segment were also different. The 98th percentile values of well-known surrogate parameters for ventricular hypertrophy in the present study were much higher than the conventional criteria.

CONCLUSIONS

The present study of a large number of pediatric subjects showed that the effects of age and sex on ECG parameters are different, and that criteria for ventricular hypertrophy should be newly determined by age and sex. We have developed reference data for STJ segment elevation for children and adolescents. These findings are useful for creating guidelines and recommendations for interpretation of pediatric ECG.

Resolution of Abnormal Body Surface Maps in Children with Atrial Septal Defect after Intracardiac Repair

INTRODUCTION

The genesis of repolarization abnormalities of ECG waveforms in atrial septal defect (ASD), which typically is characterized by right ventricular (RV) volume overload, has not been explored, particularly in association with postoperative hemodynamic improvement. The aim of this study was to evaluate the effects of reduced RV overload after ASD closure on depolarization and repolarization abnormalities on body surface maps (BSMs).

METHODS AND RESULTS

BSMs of 14 children with ASD were recorded preoperatively and at early postoperative (1-6 months) and late postoperative (>9 months) stages. BSMs of 31 age-matched healthy children were studied as normal controls. Before intracardiac repair, QRS isopotential maps of children with ASD showed delayed RV breakthrough and subsequent rightward enlargement of the positive area with a maximum shifting to the right. Delayed conduction of the RV, particularly at the outflow tract area, was noted. The preoperative QRST isointegral maps exhibited the two-maximum pattern reflecting repolarization abnormality. The delayed appearance of breakthrough and delayed RV conduction on the QRS isopotential maps persisted from the preoperative to the late postoperative stage, whereas the two-maximum pattern on the QRST isointegral maps normalized to the one-dipole pattern at an early stage after repair.

CONCLUSION

Abnormal repolarization parameters in ASD patients showed rapid improvement postoperatively, despite the persistence of depolarization abnormalities. Therefore, the two-maximum pattern on the QRST isointegral maps indicates a primary T wave change due to hemodynamic RV volume overload.

Changes in body surface potential distributions induced by isoproterenol and Na channel blockers in patients with the Brugada syndrome

BACKGROUND

The characteristics of unique ECG findings in the Brugada syndrome have not been well explained.

METHODS

To clarify their characteristics and mechanisms, body surface maps (BSM) were recorded from patients with the Brugada syndrome (13 cases; a mean age of 48 years) before and after administration of isoproterenol (ISP) or Na channel blockers (12 cases).

RESULTS

ST elevation in V1-V3 was decreased by 0.1 mV or more after ISP infusion in 8 of 11 cases and elevated after Na channel blockers in 8 of 12. In ventricular activation time (VAT) isochronal map, delayed conduction was noted on upper anterior chest in 11 and on anterior left chest in two. Delayed conduction areas were decreased by ISP and expanded by Na channel blockers. QRST isointegral map showed normal findings in baseline with minimal changes after ISP or Na channel blockers. Activation recovery interval (ARI) isochronal map showed prolonged area on upper anterior chest in baseline, being reduced by ISP and expanded by Na channel blockers. ARI dispersion (ARI-d), defined as difference between the maximum and minimum value of ARI, was larger in Brugada patients than that of normal subjects in baseline, and decreased after ISP and increased after Na channel blockers.

CONCLUSION

ST elevation in the Brugada syndrome is primarily caused by abnormality in depolarization rather than in repolarization. BSM can provide better information to clarify a mechanism of ECG changes adding its diagnostic value for this unique syndrome.

Who Is at Risk for Cardiac Events in Young Patients With Long QT Syndrome?

The objective of this study was to determine who is at risk for cardiac events among young patients with long QT syndrome (LQTS) with or without a past history of LQTS-related cardiac events. The subjects were young patients with LQTS who had visited one of 36 hospitals from January 1997 to August 2000 in Japan. To predict the risk factors for cardiac events, stepwise regression analyses were performed for a total of 197 cases. There were 7 of 129 cases (5%) without a past history and 32 of the 68 (47%) cases with a past history of LQTS-related cardiac events that experienced new events after diagnosis (p<0.0001). Patients with a family history showed a higher incidence of symptoms both before and after diagnosis than patients with sporadic occurrence. Analyses revealed that noncompliance with medication and a lower age at diagnosis were significant predictors for the group with a past history. A negative predictive value <4 points was 100% in the group without a past history. To prevent future cardiac events, compliance with medication must be improved in those with a past history. A total LQTS score <4 points was useful to predict the absence of cardiac events in the group without a past history.

Moving dipole analysis of normal and abnormal ventricular activation by magnetocardiography

The current source during ventricular excitation of the in situ heart has not been well characterized. We analyzed current dipoles of ventricular excitation by magnetocardiography (MCG) in 16 healthy subjects and 10 patients with the Wolff-Parkinson-White syndrome or premature ventricular contraction. Single current dipoles were estimated by MCG with the spatial position, direction, and strength in the initial 40 ms of QRS (moving dipole analysis). In 12 of the 16 healthy subjects, the origin of current dipoles moved consecutively from the initial position with the increase in the peak strength at 30 ms of QRS. In the other 4 healthy subjects, dipoles moved discontinuously jumping to the right-anterior thorax at 17.8 ms (mean). In abnormal ventricular excitation, the dipoles remained in the initial position with little movement, smaller strength of dipole than that of normal with a delayed peak time. The moving dipole analysis can be applied to determine spatial distribution of normal and abnormal excitation sources at the initial phase of ventricular depolarization in the in situ heart.

Analysis of T wave changes by activation recovery interval in patients with atrial septal defect

We examined the distributions of the activation recovery interval (ARI), which is correlated with the local action potential duration (APD), to clarify the origin of the repolarization changes in ASD. The ECGs, QRST isointegral maps and ARI isochronal maps of 21 children with ASD from 3 to 5 years old in age were studied in comparison with 21 age-matched normal children. A conventional and 87 unipolar body surface ECG were simultaneously recorded. The ARIs were determined from the first derivatives of the ECG waveforms. Abnormal ST-T patterns were observed in 11 of 21 ASD, but only in two normal children. The QRST maps of a split positive area pattern were seen in 15 of ASD but none of the normal. In the ARI maps, all the normal children exhibited a short-ARI area on the left and a long-ARI area on the right side of the chest. In 19 of ASD, the ARI distribution revealed a leftward extension of the long-ARI area on the anterior chest, a relative shortening on the right anterior chest, and a localized prolonged ARI on the left anterior chest. The results suggest that right ventricular (RV) volume overload in ASD produces a localized prolongation of the APD on the RV epicardium.

Augmentation of QRS wave amplitudes in the precordial leads during narrow QRS tachycardia

INTRODUCTION

QRS morphology during narrow QRS supraventricular tachycardia in patients without ventricular preexcitation generally is considered the same as that seen during sinus rhythm. This study presents a new ECG observation that the QRS amplitude increased significantly in leads V2 through V5 during tachycardia.

METHODS AND RESULTS

Using the same ECG machine and the same electrode patches applied to the same electrode positions, 12-lead ECGs during sinus rhythm and narrow QRS tachycardia were analyzed comparatively in 23 patients without ventricular preexcitation. Precordial QRS amplitudes were measured as the vertical distance from the peak of the R to the nadir of the S wave. The amplitudes also were measured during atrial rapid pacing and extrastimulation. Furthermore, ventricular excitation during sinus rhythm and tachycardia was studied using body surface mapping. Body surface distributions of QRS potentials and ventricular activation time (VAT) were displayed as maps. Gross area of QRS (AQRS, equivalent to the QRS amplitude) was compared during sinus rhythm versus tachycardia. During tachycardia, QRS amplitude significantly increased in leads V2 through V5, without any noticeable change in the transitional zone or QRS wave duration. Increase of QRS amplitude also was noted during atrial rapid pacing and extrastimulation. Gross AQRS values during tachycardia significantly increased in the left parasternal area, whereas QRS isopotential and VAT isochronal maps were similar during sinus rhythm and tachycardia, suggesting a minimal role of conduction delay in the increase of QRS amplitude.

CONCLUSION

QRS wave amplitude significantly increased in leads V2 through V5 during narrow QRS tachycardia compared with QRS waves in sinus rhythm. Increase of QRS amplitude seemed unlikely due to a conduction delay within the ventricular myocardium.

Non-dipolarity of heart potentials estimated by magnetocardiography in normal subjects

We studied non-dipolarity characteristics during ventricular excitation in normal adults and children by magnetocardiography (MCG) by recording magnetic field on the thorax. The source and currents of the electrical dipole from the onset up to 60 ms of ventricular excitation were analyzed in 16 adults and 5 children. A single equivalent current dipole (ECD) was estimated by Sarvas' formula for the sphere model at 1 ms intervals. The non-dipole value (NDV) was calculated from the magnetic field strength at each recording point and theoretically estimated by ECD, representing an index for the non-dipolarity. At 32-34 ms from the beginning of QRS, the mean NDV was a minimum in all subjects suggesting at least a non-dipole component during this period. High NDV (over 5%) were present in most subjects in both the early and late phase compared to this period. Thirteen of 16 adults had a high NDV in the early phase (9.3 +/- 3.0%, mean +/- SD) and all 16 subjects had a high NDV in the late phase (21.5 +/- 10.5%). All 5 children had high NDV in both the early (10.5 +/- 5.4%) and late phases (16.8 +/- 7.9%). A single ECD estimation by MCG showed a relatively low non dipolar component and MCG could be applied to the clinical evaluation of cardiac excitation in both normal and pathological conditions.

Precordial leads QRST time integrals for evaluation of right ventricular overload in children with congenital heart diseases

It was previously shown that body surface QRST isointegral maps of the anterior chest were abnormal in patients with right ventricular overload and that the abnormalities varied with hemodynamic status. The QRST isointegral maps were first characterized by using a departure index map for normal controls. The study group consisted of 14 patients with pulmonary stenosis (PS), 20 with tetralogy of Fallot, (TOF) and 43 with atrial septal defect (ASD). The QRST isointegral maps of these three groups were compared with the data on 23 to 65 age-matched normal children. In mean departure index maps, the patients with right ventricular pressure overload (PS or TOF) showed an increase in departure index on the anterior midchest, while those of right ventricular volume overload (ASD) showed two maxima on the anterior and left lateral chest, with a trough-like negative area between them. Since the abnormal findings were seen on the anterior chest, we evaluated the diagnostic usefulness of QRST time integral values for precordial leads of the routine electrocardiogram (ECG) in a second part of this study. The precordial QRST time integral values from 9 patients with PS and 11 with TOF (0-2 years of age, mean 1.1 years) and 22 ASD patients (6-15 years, mean 10.1 years) were compared with those of the age-matched control children. The QRST time integral values of the precordial leads in right ventricular pressure overload were significantly increased in the right precordial leads (V1, V2). In right ventricular volume overload, the QRST time integral values of the V1, V2, V4, and V6 leads demonstrated a significant deviation from those of the control group. Therefore, a discrimination formula was constructed by using the values of these leads, and the criteria derived from this formula revealed good (98%) diagnostic accuracy. In detection of right ventricular overload, the QRST time integral values of the precordial lead ECG, if confirmed in a larger data set, may be useful as a simple screening method.

Bovine herpesvirus meningoencephalitis association with infectious bovine rhinotracheitis (IBR) vaccine

During 1992, on a farm in the Tokachi district of Hokkaido, Japan, approximately 20 Holstein-Friesian calves showed neuroparalysis and died within 7-10 days after routine vaccination. Six male calves, aged about 1.5 months, were submitted to our laboratory for pathological examination and diagnosed as acute or subacute necrotizing meningoencephalitis due to bovine herpes virus (BHV) infection. The main necropsy findings included a few hemorrhages or clots, and malacic lesions localized in the cortical to subcortical area of the cerebrum. Histopathological brain lesions were characterized by laminar or focal necrosis of neurons, accompanying macrophages, polymorphonuclear cell infiltration, severe astrogliosis, and perivascular cuffing in all six calves. Nuclear basophilic inclusion bodies, which showed positive reaction with immunocytochemical staining of BHV antigen, were observed in the necrotic neurons, astroglia and oligodendroglia in five affected calves. BHV antigens were also seen in the cell bodies and cell processes of the necrotic neurons, which was indicative of cell-to-cell propagation of infection. There was a general tendency for more severe lesions to be located at the cortex to subcortex of the cerebrum. Milder lesions were observed in the cerebellum and brain stem. These findings suggest that the infectious route to the cerebrum in the present cases was through the olfactory bulbs and/or along the meninges beginning from the ethmoid bone, rather than through the trigeminal ganglia route as had been emphasized in studies dealing with experimental infection.

Diagnosis of right ventricular overload by body surface QRST isointegral maps in children with postoperative right bundle branch block

The utility of body surface QRST isointegral maps (QRST-Imaps) for the detection of right ventricular (RV) overload was examined in children with postoperative development of right bundle branch block. In healthy children with no evidence of bundle branch block (n = 31), the QRST-Imap demonstrated a maximum at the left anterior chest and a minimum near the right shoulder with a single dipole distribution. The positive areas extended from the left anterior chest to the left back, and negative areas extended from the right anterior chest to the right back. Children with complete right bundle branch block but without heart disease demonstrated a QRST-Imap that was similar to that seen in normal children. In patients with RV overload (n = 15; 8 with ventricular septal defect and complicated anomaly and 7 with tetralogy of Fallot), the QRST-Imaps were abnormal and demonstrated double maxima, a rightward shift of the maximum, and extension of positive areas to the right chest. In the 10 patients who developed postoperative complete right bundle branch block, 4 had no evidence of RV overload by hemodynamic or echocardiographic assessment and demonstrated a normal QRST-Imap. In the six children who had residual RV overload during hemodynamic assessment, the QRST-Imap was abnormal. These results suggest that the QRST-Imap is a useful method for the detection of RV overload in pediatric patients complicated with conduction disturbances.

QRST isointegral map reflects the sudden reduction of right ventricular pressure after balloon pulmonary valvuloplasty

To elucidate the mechanism of electrocardiographic changes due to right ventricular pressure overload, serial changes on body surface maps recorded in two children with valvular pulmonary stenosis before and after successful reduction of right ventricular pressure by balloon valvuloplasty (BVP) were studied. Body surface maps and 12-lead electrocardiograms were simultaneously recorded before and 1-1.5 hours, 8 hours, and 5 days after BVP. Before BVP, QRST isointegral maps showed either two maxima or an expanded single maximum on the right anterior chest. These abnormal characteristics become normal or near normal 1-1.5 hours after BVP. Electrocardiographic waveforms and QRS and ST-T isointegral maps showed minimal changes. Changes in QRST isointegral maps were observed near the center of the midanterior chest. These results suggest that increased right ventricular pressure caused a primary repolarization abnormality in the mid-anterior chest that was easily detected by body surface QRST isointegral maps.

The body surface QRST isointegral maps in infants with right ventricular overload

Electrocardiographic criteria for right ventricular (RV) hypertrophy in infants generally exhibit low sensitivity in terms of diagnostic accuracy. We studied the QRST isointegral map (QRST-Imap) of body surface potential distribution for the diagnosis of RV overload in patients less than 2 years old. Patients with atrial septal defect (ASD), pulmonary stenosis (PS) and tetralogy of Fallot (TOF) were examined (RV overload group) and the findings of their QRST-Imaps were compared to those of age-matched healthy infants (NOR). QRST-Imaps in RV overload showed abnormal findings, with two maxima or a rightward shift of the maximum with increased amplitude, in contrast to one maximum at the left anterior chest with a single dipole pattern in the NOR group. ASD patients had two maxima with a decreased integral value between them. In PS, two maxima were also observed, with increased integral values of the right maximum as the RV systolic pressure was elevated. TOF patients showed a single maximum shifted to the anterior median line with increased amplitude. These results indicate that the findings of QRST-Imaps are of value in detecting the presence and pattern of RV overload in infants.

Criterion for early prediction of coronary artery involvement by clinical manifestations in patients with Kawasaki disease

One hundred and thirty patients with Kawasaki disease were examined by the clinical symptoms and findings in order to predict the coronary artery involvement in the early stage. These patients were tested by the two-dimensional echocardiography iteratively from the acute stage and categorized into the following three groups: Normal coronary artery, transient dilatation of the coronary artery and aneurysm of the coronary artery persisting eight weeks or more after the onset of the illness. Eighteen clinical symptoms and findings within the 14th, 21st and 35th day of the illness were studied. As a result of analysis, a criterion for the early prediction of the coronary artery involvement by clinical manifestations was established as follows: The patients who satisfy the following or are highly suspectable of having a coronary artery involvement: Fever persisting for 14 days or more. Fever persisting for 10 to 13 days, and when two or more out of the following four conditions are satisfied: The age at the onset of the illness is under one year. The lowest value of hemoglobin is 10.0 g/dl or less. The highest white blood cell count is 14000/cmm or more. The lowest value of serum albumin is 3.5 g/dl or less. Two false negative cases (6.5%) were recognized in 31 of the high risk group. Twenty-two false positive cases (22.2%) were observed in 99 of the normal group. One hundred and six cases out of the 130 cases (81.5%) satisfied this criterion. Therefore, this criterion was concluded to be useful to predict the coronary artery involvement in the earlier stage of the illness.

Detection of coronary arterial lesions by two dimensional echocardiography in patients with Kawasaki disease

A two-dimensional echocardiographic examination was conducted on 184 patients with Kawasaki disease iteratively from the acute phase to the convalescent phase. Aneurysms or dilatation of the coronary arteries were observed in 37 patients (20.1%). Among these 37 patients, 22 had persistent abnormality even after eight weeks from the onset. In the remaining 15 patients, abnormal findings disappeared within eight weeks. Coronary angiography was performed on all of these 37 patients and compared with the findings of echocardiography. In consequence, echocardiographic findings were concordant with those of the angiography in 35 patients. Therefore, the two-dimensional echocardiographic examination is thought to be a reliable noninvasive method for evaluating the coronary arterial lesions of Kawasaki disease in the acute phase.