Electroacupuncture Ameliorates Acute Myocardial Ischemic Injury and Long QT Interval in Mice through the α1A-Adrenergic Receptor: Electrophysiological, Morphological, and Molecular Evidence

Acute myocardial ischemia (AMI) is a condition caused by a decrease in blood flow to the heart that can sometimes predispose to acquired long QT syndrome (LQTS), thereby resulting in sudden cardiac death. Recent evidence indicates that electroacupuncture (EA) can alleviate MI injury, but its specific mechanism remains unclear. This study was aimed at investigating the efficacy of EA, which utilizes α_1A-adrenergic receptors (α_1A-AR) in alleviating MI injury as well as the resulting LQTS. The AMI model was established by ligating the left anterior descending arteries (LAD) of both the wild-type and α_1A gene-knockout mice and treating them with EA for three consecutive days. A PowerLab 16 physiological recorder was used to collect the electrocardiogram (ECG) while the serum creatine kinase isoenzymes (CK-MB), lactate dehydrogenase (LDH), and norepinephrine (NE) levels in myocardial tissue were determined by using the enzyme-linked immunosorbent assay (ELISA) kit. Moreover, TTC staining was used to observe the myocardial ischemic area, while H&E and TUNEL staining determined the pathological morphology of the myocardium. Quantitative real-time PCR (qRT-PCR) was used to detect the α_1A mRNA, and Western blot was used to detect the specific proteins, such as α_1A, cleaved caspase-3, Gq, PLC, p-PKCα, and p-hERG. Our results showed that EA could effectively reduce elevated ST-segment, shorten the extended QT interval, and reduce the serum myocardial enzyme content and the degree of pathological injury in wild mice with MI. EA can also decrease the expression of α_1A-AR, PLC, p-PKCα, and NE content in myocardial tissues of wild mice, while those of p-hERG increased in ischemic myocardial tissue. These findings suggested that α_1A-AR is involved in the development of MI as well as LQTS. Additionally, EA treatment improves the cardiac function and ischemic long QT interval and plays an important role in reducing the hERG inhibition through the α_1A-AR-mediated Gq/PLC/PKCα pathway and myocardial apoptosis. Hence, it is suggested that α_1A-AR might become a potential target for EA in treating AMI treatment of myocardial ischemia injury and acquired long QT intervals caused by MI.

Impaired left ventricular systolic synchrony in patients with lupus Nephritis: A speckle tracking echocardiography study

OBJECTIVES

We aimed to explore the value of two-dimensional speckle tracking echocardiography measurements of the global longitudinal strain (GLS) and left ventricular mechanical dispersion (LVMD) in the assessment of early stage left ventricular systolic dysfunction and heterogeneity of myocardial contraction in patients with lupus nephritis (LN).

METHODS

Patients with LN and extra-renal systemic lupus erythematosus (SLE) and healthy participants in the control group underwent echocardiography for the traditional measurement of the left ventricular systolic and diastolic function and speckle tracking measurements of the GLS and LVMD. GLS was defined as the average value of the peak strain during systole of the left ventricular 17 segments, and LVMD was defined as the standard deviation. The demographic characteristics including age, sex, and body mass index (BMI) of all the participants were collected. The clinical and laboratory characteristics of the patients with LN were collected.

RESULTS

We included 41 healthy control, 37 patients with extra-renal SLE, and 73 patients with LN. There were statistically significant differences in the GLS and LVMD between the extra-renal SLE and LN groups (GLS -19.36% vs. -17.61%, p < 0.001; LVMD 35.62 ms vs 42.96 ms, p<0.001). There was a statistically significant difference in the LVMD between the extral-renal SLE and control groups (35.62ms vs 25.51ms, p<0.001), but not in GLS (-19.36% vs -19.52%, p > 0.05). Multiple regression analyses were conducted in a subset of patients, and 24-hour proteinuria was independently associated with LVMD (β [SE], 0.793 [0.302], p < .05).

CONCLUSIONS

Patients with LN have more severe myocardial involvement than patients with extra-renal SLE. The asynchrony in myocardial contraction represented by the LVMD can be recognized earlier than that of the overall contractile functional impairment represented by GLS. In patients with LN, the 24-hour proteinuria was associated with LVMD. This indicates that the heterogeneity in the contractile function may be associated with the severity of renal damage.

Myocardial electrophysiological and mechanical changes caused by moderate hypothermia-A clinical study

Moderate hypothermia has been used to improve outcomes in comatose out-of-hospital cardiac arrest survivors during the past two decades, although the effects remain controversial. We have recently shown in an experimental study that myocardial electrophysiological and mechanical relationships were altered during moderate hypothermia. Electromechanical window positivity increased, and electrical dispersion of repolarization decreased, both of which are changes associated with decreased arrhythmogenicity in clinical conditions. Mechanical dispersion, a parameter also linked to arrhythmic risk, remained unaltered. Whether corresponding electrophysiological and mechanical changes occur in humans during moderate hypothermia, has not been previously explored. Twenty patients with normal left ventricular function were included. Measurements were obtained at 36 and 32°C prior to ascending aortic repair while on partial cardiopulmonary bypass and at 36°C after repair. Registrations were performed in the presence of both spontaneous and comparable paced heart rate during standardized loading conditions. The following electrical and mechanical parameters were explored: (1) Electromechanical window, measured as time difference between mechanical and electrical systole, (2) dispersion of repolarization from ECG T-wave, and (3) mechanical dispersion, measured as segmental variation in time to peak echocardiographic strain. At moderate hypothermia, mechanical systolic prolongation (425 ± 43-588 ± 67 ms, p < 0.001) exceeded electrical systolic prolongation (397 ± 49-497 ± 79 ms, p < 0.001), whereby, electromechanical window positivity increased (29 ± 30-86 ± 50 ms, p < 0.001). Dispersion of repolarization and mechanical dispersion remained unchanged. Corresponding electrophysiological and mechanical relationships were present at comparable paced heart rates. After rewarming, the increased electromechanical window was reversed in the presence of both spontaneous and paced heart rates. Moderate hypothermia increased electromechanical window positivity, while dispersion of repolarization and mechanical dispersion remained unchanged. This impact of hypothermia may be clinically relevant for selected groups of patients after cardiac arrest.

Left ventricular mechanical dispersion in a general population: Data from the Akershus Cardiac Examination 1950 study

AIMS

Increased left ventricular mechanical dispersion by 2D speckle tracking echocardiography predicts ventricular arrhythmias in ischaemic heart disease and heart failure. However, little is known about mechanical dispersion in the general population. We aimed to study mechanical dispersion in the general population and in diseases associated with increased risk of cardiovascular disease.

METHODS AND RESULTS

The present cross-sectional study consists of 2529 subjects born in 1950 included in the Akershus Cardiac Examination (ACE) 1950 study. Global longitudinal strain (GLS) was assessed from 17 strain segments, and mechanical dispersion calculated as the standard deviation of contraction duration of all segments. The cohort was divided according to the median value of mechanical dispersion, and multivariable linear regression models were performed with mechanical dispersion as the dependent variable. The prevalence of coronary artery disease (CAD), hypertension, obesity, and diabetes (P < 0.01 for all) was significantly higher in subjects with supra-median mechanical dispersion. In a multivariable clinical model, CAD (B = 7.05), hypertension (B = 4.15; both P < 0.001), diabetes (B = 3.39), and obesity (B = 1.89; both P < 0.05) were independently associated with increasing mechanical dispersion. When echocardiographic indices were added to the multivariable model, CAD (B = 4.38; P < 0.01) and hypertension (B = 2.86; P < 0.001) remained significant in addition to peak early diastolic tissue velocity e' (B = -2.00), GLS (B = 1.68), and ejection fraction (B = 0.22; P < 0.001 for all).

CONCLUSION

In a general middle-aged population, prevalent CAD and hypertension were associated with increasing mechanical dispersion, possibly indicating elevated risk of fatal arrhythmias and sudden cardiac death. Albeit weaker, systolic and diastolic dysfunction, were also associated with increasing mechanical dispersion.

Left ventricular mechanical dispersion in ischaemic cardiomyopathy: association with myocardial scar burden and prognostic implications

AIMS

Left ventricular (LV) mechanical dispersion (MD) may result from heterogeneous electrical conduction and is associated with adverse events. The present study investigated (i) the association between LV MD and the extent of LV scar as assessed with contrast-enhanced cardiac magnetic resonance (CMR) and (ii) the prognostic implications of LV MD in patients after ST-segment elevation myocardial infarction.

METHODS AND RESULTS

LV MD was calculated by echocardiography and myocardial scar was analysed on CMR data retrospectively. Infarct core and border zone were defined as ≥50% and 35-50% of maximal signal intensity, respectively. Patients were followed for the occurrence of the combined endpoint (all-cause mortality and appropriate implantable cardioverter-defibrillator therapy). In total, 96 patients (87% male, 57 ± 10 years) were included. Median LV MD was 53.5 ms [interquartile range (IQR) 43.4-62.8]. On CMR, total scar burden was 11.4% (IQR 3.8-17.1%), infarct core tissue 6.2% (IQR 2.0-12.7%), and border zone was 3.5% (IQR 1.5-5.7%). Correlations were observed between LV MD and infarct core (r = 0.517, P < 0.001), total scar burden (r = 0.497, P < 0.001), and border zone (r = 0.298, P = 0.003). In total, 14 patients (15%) reached the combined endpoint. Patients with LV MD >53.5 ms showed higher event rates as compared to their counterparts. Finally, LV MD showed the highest area under the curve for the prediction of the combined endpoint.

CONCLUSION

LV MD is correlated with LV scar burden. In addition, patients with prolonged LV MD showed higher event rates. Finally, LV MD provided the highest predictive value for the combined endpoint when compared with other parameters.

Incremental value of QT interval for the prediction of obstructive coronary artery disease in patients with chest pain

Identification of obstructive coronary artery disease (OCAD) in patients with chest pain is a clinical challenge. The value of corrected QT interval (QTc) for the prediction of OCAD has yet to be established. We consecutively enrolled 1741 patients with suspected angina. The presence of obstructive OCAD was defined as ≥ 50% diameter stenosis by coronary angiography. The pre-test probability was evaluated by combining QTc prolongation with the CAD Consortium clinical score (CAD2) and the updated Diamond-Forrester (UDF) score. OCAD was detected in 661 patients (38.0%). QTc was longer in patients with OCAD compared with those without OCAD (444 ± 34 vs. 429 ± 28 ms, p < 0.001). QTc was increased by the severity of OCAD (P < 0.001). QTc prolongation was associated with OCAD (odds ratio (OR), 2.27; 95% confidence interval (CI), 1.81–2.85). With QTc, the C-statistics increased significantly from 0.68 (95% CI 0.66–0.71) to 0.76 (95% CI 0.74–0.78) in the CAD2 and from 0.64 (95% CI 0.62–0.67) to 0.74 (95% CI 0.72–0.77) in the UDF score, respectively. QT prolongation predicted the presence of OCAD and the QTc improved model performance to predict OCAD compared with CAD2 or UDF scores in patients with suspected angina.

Evaluation of left ventricular systolic synchrony by peak strain dispersion in patients with rheumatoid arthritis

Objective

To investigate the clinical value of the peak strain dispersion (PSD) in evaluating left ventricular (LV) systolic synchrony in patients with rheumatoid arthritis (RA).

Methods

One hundred eleven patients with RA were divided into two groups according to their disease duration: <5 years (Group I, n = 60) and ≥5 years (Group II, n = 51). The control group comprised 57 healthy subjects without RA. All three groups were examined by transthoracic two-dimensional echocardiography. Traditional parameters were measured by conventional echocardiography. Two-dimensional speckle tracking imaging was used to analyze the PSD and LV global longitudinal strain (LVGLS). Related ultrasound and blood test results were analyzed and compared.

Results

The PSD gradually increased in the order of the control group, Group I, and Group II, and the difference among the groups was statistically significant. The LVGLS gradually decreased in the order of the control group, Group I, and Group II, and the difference among the groups was statistically significant. The PSD was negatively correlated with the LVGLS.

Conclusions

LV systolic synchrony in patients with RA gradually decreases as the disease course progresses. The PSD can be used as a new reliable index to evaluate LV systolic synchrony.

Rapidly and Accurately Detecting Significant Coronary Artery Stenosis in Patients with Suspected Stable Coronary Artery Disease and Normal Segmental Wall Motion by Speckle Tracking Automated Functional Imaging

This study was performed to explore the value of a machine with built-in speckle tracking automated functional imaging (AFI) in predicting the severity of coronary artery lesions in patients with suspected stable coronary artery disease (SCAD) with normal wall motion. One hundred forty-three consecutive patients with clinically suspected SCAD with normal wall motion were included. Multiple parameters, including global longitudinal peak strain, post-systolic index (PSI) and peak strain dispersion, were automatically analyzed with AFI. Territorial longitudinal strain (TLS) and territorial PSI (TPSI) were also calculated. Receiver operating characteristic curve analyses revealed that global longitudinal peak strain and PSI were superior to other parameters in detecting left main or three-vessel SCAD. A combination of TLS and TPSI could improve diagnostic performance in identifying significant stenotic left anterior descending and right coronary arteries. In conclusion, 2-dimensional speckle tracking AFI can rapidly provide multiple parameters for detecting significant coronary artery stenosis with high accuracy in patients suspected of having SCAD with normal wall motion.

Changes in left ventricular electromechanical relations during targeted hypothermia

Background

Targeted hypothermia, as used after cardiac arrest, increases electrical and mechanical systolic duration. Differences in duration of electrical and mechanical systole are correlated to ventricular arrhythmias. The electromechanical window (EMW) becomes negative when the electrical systole outlasts the mechanical systole. Prolonged electrical systole corresponds to prolonged QT interval, and is associated with increased dispersion of repolarization and mechanical dispersion. These three factors predispose for arrhythmias. The electromechanical relations during targeted hypothermia are unknown.

We wanted to explore the electromechanical relations during hypothermia at 33 °C. We hypothesized that targeted hypothermia would increase electrical and mechanical systolic duration without more profound EMW negativity, nor an increase in dispersion of repolarization and mechanical dispersion.

Methods

In a porcine model (n = 14), we registered electrocardiogram (ECG) and echocardiographic recordings during 38 °C and 33 °C, at spontaneous and atrial paced heart rate 100 beats/min. EMW was calculated by subtracting electrical systole; QT interval, from the corresponding mechanical systole; QRS onset to aortic valve closure. Dispersion of repolarization was measured as time from peak to end of the ECG T wave. Mechanical dispersion was calculated by strain echocardiography as standard deviation of time to peak strain.

Results

Electrical systole increased during hypothermia at spontaneous heart rate (p < 0.001) and heart rate 100 beats/min (p = 0.005). Mechanical systolic duration was prolonged and outlasted electrical systole independently of heart rate (p < 0.001). EMW changed from negative to positive value (− 20 ± 19 to 27 ± 34 ms, p = 0.001). The positivity was even more pronounced at heart rate 100 beats/min (− 25 ± 26 to 41 ± 18 ms, p < 0.001). Dispersion of repolarization decreased (p = 0.027 and p = 0.003), while mechanical dispersion did not differ (p = 0.078 and p = 0.297).

Conclusion

Targeted hypothermia increased electrical and mechanical systolic duration, the electromechanical window became positive, dispersion of repolarization was slightly reduced and mechanical dispersion was unchanged. These alterations may have clinical importance. Further clinical studies are required to clarify whether corresponding electromechanical alterations are accommodating in humans.

Correlates and Long-Term Implications of Left Ventricular Mechanical Dispersion by Two-Dimensional Speckle-Tracking Echocardiography in Patients with ST-Segment Elevation Myocardial Infarction

BACKGROUND

Left ventricular (LV) mechanical dispersion (LVMD), measured with speckle-tracking echocardiography (STE) after ST-segment elevation myocardial infarction (STEMI), has been proposed as a measurement of regional heterogeneity of myocardial contraction and may reflect changes in the myocardial structure (e.g., fibrosis or edema). Further insight into this parameter may aid in the risk stratification of STEMI patients.

METHODS

A total of 1,000 STEMI patients (77% male, 60 ± 12 years) treated with primary percutaneous coronary intervention were retrospectively analyzed. The LVMD was assessed with two-dimensional STE within 48 hours following the index infarction. Patients were followed for the occurrence of all-cause mortality.

RESULTS

After a median follow-up of 117 months, 229 (23%) patients died. Nonsurvivors showed worse LV ejection fraction (43% ± 10% vs 48% ± 9%; P < .001) and global longitudinal strain (-12.0% ± 3.5% vs -14.2% ± 3.5%; P = .001) and prolonged LVMD (63 [interquartile range, 50-85] msec vs 52 [interquartile range, 42-63] msec; P < .001) compared with survivors. Increasing age, systolic blood pressure, and heart rate at discharge as well as diabetes mellitus, anterior STEMI, TIMI flow < 2, less usage of angiotensin converter enzyme inhibitors or angiotensin receptor blockers, and impaired LV global longitudinal strain were independently associated with more prolonged LVMD. On multivariable analysis, prolonged LVMD was independently associated with increased risk of all-cause mortality (hazard ratio = 1.012; 95% CI, 1.005-1.018; P = .001) and had incremental value for all-cause mortality over clinical and echocardiographic parameters.

CONCLUSIONS

In contemporary STEMI patients, prolonged LVMD was associated with various clinical and echocardiographic parameters. Prolonged LVMD was associated with worse long-term outcome.

Prognostic importance of mechanical dyssynchrony in predicting heart failure development after ST-segment elevation myocardial infarction

The aim of this study is to assess the prognostic value of mechanical dyssynchrony defined as the standard deviation of the time to peak longitudinal strain (SD T2P LS) in predicting the development of heart failure (HF) after an ST-segment elevation myocardial infarction (STEMI). Three hundred and seventy-three patients were admitted with STEMI and treated with primary percutaneous coronary intervention. Left ventricular (LV) mechanical dyssynchrony was examined through speckle tracking echocardiography and defined as SD T2P LS. The association with the outcome of HF hospitalization was assessed using Cox proportional hazard models. During a median follow-up of 5.12 years, 144 patients (38.6%) were admitted due to HF. Worse dyssynchrony was associated with the outcome in unadjusted and multivariable analysis (multivariable hazard ratio 1.05, 95% confidence interval 1.00-1.10, p-value 0.039, per 10 ms increase), but not after further adjustment for LV ejection fraction (LVEF), E/e' and global longitudinal strain (GLS) (hazard ratio 1.01, 95% confidence interval 1.00-1.07, p-value 0.71, per 10 ms increase), nor in a model only adjusting for GLS (hazard ratio 1.01, 95% confidence interval 1.00-1.06, p-value 0.61, per 10 ms increase). These findings were reproduced in a competing risk analysis treating all-cause mortality as a competing risk. LV mechanical dyssynchrony, as assessed by SD T2P LS is not an independent predictor of post-STEMI HF development and mechanical dyssynchrony does not provide independent prognostic information regarding HF when GLS is known.

Rhythm and orthopedics: The effect of music therapy in cast room procedures, a prospective clinical trial

INTRODUCTION

Cast room procedures generally cause anxiety in patients. Anxiety complicates the procedure as well as increases the risk of a complication. Listening to music was found to be the safest and most common non-drug treatment method. The aim of this study is to evaluate the effect of listening to music on adult patients in cast room procedures. This study points out the relation between anxiety and anxiety relevant cardiac arrhythmia.

MATERIALS AND METHODS

The study was performed on 199 patients with stable general condition, aged above 18. The patients were divided into two groups. Randomization method used in the study was coin flip. The first group (Group 1) listened to music during cast room procedures whereby the second group (Group 2) did not listen to music. Length of the procedure, complication, blood pressure and heart rate evaluations before and after the procedure, Visual Analogue Scale (VAS scores for pain), State-Trait Anxiety Inventory (STAI) anxiety score, patient satisfaction, willingness of the patient to repeat the procedure, P wave dispersion (Pd) and corrected QT interval dispersion (QTcd) as electrocardiographic arrhythmia predictors were evaluated. The Clinical Research Ethics Committee approval was obtained for this study.

RESULTS

Significant difference was shown between the two groups for the following criteria: VAS scores (p = 0.005), anxiety scores (p = 0.032), processing time (p = 0.027), and QTcd values (p = 0.031). Patient satisfaction (p < 0.001) and willingness to repeat the procedure (p < 0.001) were higher for the group who listened to music. No significant difference in Pd values, blood pressure and heart rate was reported within the groups.

CONCLUSION

Music therapy is a non-invasive, safe, nonpharmacologic, anxiolytic, and analgesic treatment. Music therapy should become standard protocol in cast room procedures. One of the most important achievements of this study was the fact that music decreases anxiety and anxiety-related cardiac arrhythmia. Therefore, conducting further prospective studies including high cardiac risk patients especially with arrhythmia is crucial.

Mechanical dispersion is associated with poor outcome in heart failure with a severely depressed left ventricular function and bundle branch blocks

OBJECTIVES

Bundle branch blocks (BBB)-related mechanical dyssynchrony and dispersion may improve patient selection for device therapy, but their effect on the natural history of this patient population is unknown.

METHODS

A total of 155 patients with LVEF ≤ 35% and BBB, not treated with device therapy, were included. Mechanical dyssynchrony was defined as the presence of either septal flash or apical rocking. Contraction duration was assessed as time interval from the electrocardiographic R-(Q-)wave to peak longitudinal strain in each of 17 left ventricular segments. Mechanical dispersion was defined as either the standard deviation of all time intervals (dispersion_SD) or as the difference between the longest and shortest time intervals (dispersion_delta). Patients were followed for cardiac mortality during a median period of 33 months.

RESULTS

Mechanical dyssynchrony was not associated with survival. More pronounced mechanical dispersion_delta was found in patients with dyssynchrony than in those without. In the multivariate regression analysis, patients' functional class, diabetes mellitus and dispersion_delta were independently associated with mortality.

CONCLUSIONS

Mechanical dispersion, but not dyssynchrony, was independently associated with mortality and it may be useful for risk stratification of patients with heart failure (HF) and BBB. Key Messages Mechanical dispersion, measured by strain echocardiography, is associated with poor outcome in heart failure with a severely depressed left ventricular function and bundle branch blocks. Mechanical dispersion may be useful for risk stratification of patients with heart failure and bundle branch blocks.

T-wave changes in patients with Wellens syndrome are associated with increased myocardial mechanical and electrical dispersion

Some patients with unstable angina and critical stenosis of the left anterior descending coronary artery (LAD) present with Wellens syndrome (WS), i.e., inverted or biphasic T-waves in the anterior precordial leads. We assessed clinical, angiographic, electro- and echocardiographic characteristic of patients with WS. In this retrospective study, clinical, angiographic, electro- and echocardiographic characteristic of 35 patients with WS were compared to 57 patients with critical LAD stenosis and normal resting electrocardiogram (ECG), and 45 subjects with normal coronary angiogram. QTc dispersion was measured from the 12-lead ECG as the difference between longest and shortest QTc intervals. Mechanical dispersion was defined as the time difference between the longest and shortest contraction durations which were measured as the time from the first deflection of the QRS complex to maximum myocardial shortening of each 18 segmental longitudinal strain curves derived by speckle tracking echocardiography. There were no significant differences in the complexity and location of the LAD lesion, anterograde and collateral flow in LAD and coronary artery dominance between patients with WS and normal ECG (P > 0.05, for all). Patients with WS had lower global longitudinal strain (GLS) and more pronounced both QTc and myocardial mechanical dispersion than patients with critical LAD stenosis and normal ECG, and control subjects (P < 0.05). T-wave changes in patients with WS are associated with more profound regional myocardial dysfunction and increased QTc and myocardial mechanical dispersion. Similar angiographic characteristics of the LAD lesion were seen in patients with WS and normal ECG.

Prognostic Significance of QT Interval Dispersion in the Response to Intravenous Immunoglobulin Therapy in Kawasaki Disease

BACKGROUND

Kawasaki disease (KD) is classified as a systemic vasculitis syndrome and QT interval dispersion (QTD) has been associated with cardiac involvement and disease activity in patients with cardiovasculitis. We examined whether baseline QTD could predict a response to intravenous immunoglobulin (IVIG) in KD.Methods and Results:QTD was recorded in 86 patients with KD before IVIG, who were separated into IVIG responders (R group; n=62) and nonresponders (N group; n=24). The association between baseline QTD and response to IVIG was investigated, and the predictive response value was compared with conventional risk scores from Gunma and Kurume universities. Baseline-corrected QTDs with Bazett's (QTbcD) and Fridericia's (QTfcD) formulae were significantly increased in the N group (R group vs. N group: 31.6 [28.3, 44.0] ms vs. 66.6 [50.5, 76.3] ms and 27.4 [25.2, 39.1] ms vs. 55.2 [42.4, 66.3] ms, respectively, both P<0.001). Multiple logistic regression analysis revealed QTfcD as an independent predictor of a response to IVIG after adjustment for conventional scores (odds ratio: 1.133, 95% confidence interval: 1.061-1.210, P<0.001). Moreover, QTfcD provided incremental predictive value for IVIG nonresponders over Gunma score (increment in global χ²=25.46, P<0.001).

CONCLUSIONS

QTD was significantly associated with a response to IVIG in KD patients and may represent a useful identifier of IVIG nonresponders with high risk of coronary aneurysm.