QT Dispersion predicting acute rheumatic carditis

Parameters indicative of persistence of valvular pathology at initial diagnosis in acute rheumatic carditis: the role of albumin and CD19 expression

OBJECTIVE

The aim of this study is to define the predictors of chronic carditis in patients with acute rheumatic carditis (ARC).

METHODS

Patients diagnosed with ARC between May 2010 and May 2011 were included in the study. Echocardiography, electrocardiography, lymphocyte subset analysis, acute phase reactants, plasma albumin levels, and antistreptolysin-O (ASO) tests were performed at initial presentation. The echocardiographic assessments were repeated at the sixth month of follow-up. The patients were divided into two groups according to persistence of valvular pathology at 6th month as Group 1 and Group 2, and all clinical and laboratory parameters at admission were compared between two groups of valvular involvement.

RESULTS

During the one-year study period, 22 patients had valvular disease. Seventeen (77.2%) patients showed regression in valvular pathology. An initial mild regurgitation disappeared in eight patients (36.3%). Among seven (31.8%) patients with moderate regurgitation initially, the regurgitation disappeared in three, and four patients improved to mild regurgitation. Two patients with a severe regurgitation initially improved to moderate regurgitation (9.1%). In five (22.8%) patients, the grade of regurgitation [moderate regurgitation in one (4.6%), and severe regurgitation in 4 (18.2%)] remained unchanged. The albumin level was significantly lower at diagnosis in Group 2 (2.6±0.48g/dL). Lymphocyte subset analysis showed a significant decrease in the CD8 percentage and a significant increase in CD19 percentage at diagnosis in Group 2 compared to Group 1.

CONCLUSION

The blood albumin level and the percentage of CD8 and CD19 (+) lymphocytes at diagnosis may help to predict chronic valvular disease risk in patients with acute rheumatic carditis.

QT and P-wave dispersions in rheumatic heart disease: prospective long-term follow up

BACKGROUND

Simple electrocardiogram (ECG) markers have been used to evaluate conduction times. Acute rheumatic fever (ARF) is an autoimmune disease that affects these conduction times. The aim of this prospective long-term follow-up study was to evaluate QT, QTc and P-wave dispersions in children with ARF and chronic rheumatic heart disease (CRHD).

METHODS

Sixty-four patients with ARF, 33 patients with CRHD and 41 healthy, age- and sex-matched control subjects were included in the study. The ARF patients were divided into two subgroups: carditis and arthritis. Echocardiographic and ECG measurements at the onset of diagnosis and final evaluation were included.

RESULTS

QT, QTc and P-wave dispersions were significantly greater in both the ARF carditis and CRHD groups than the ARF arthritis and control subjects during the initial and final analysis (for all, P < 0.001). There was no significant statistical difference in QT, QTc and P-wave dispersion between the initial and final analysis in each groups. Severity of mitral regurgitation and left atrial enlargement were found to be positively correlated with P-wave dispersion (r = 0.438, P < 0.001; r = 0.127, P < 0.001, respectively). QT, QTc and P-wave dispersion greater than 52, 60 and 57 ms, respectively, had higher sensitivity and specificity for predicting ARF carditis.

CONCLUSION

These ECG measurements can be used in the diagnosis of ARF carditis as minor criteria with modified Jones criteria. In contrast, this increase in the dispersions is permanent in patients with ARF carditis.

Prevalence of electrocardiogram use in infants with apparent life-threatening events: a multicenter database study

OBJECTIVE

An apparent life-threatening event (ALTE) is a common diagnosis in pediatrics, but there is no standardized method to evaluate these patients. We sought to determine the prevalence of electrocardiogram (ECG) use in patients presenting to children's hospitals with an ALTE.

METHODS

The data from the Pediatric Health Information System database from 43 children's hospitals were collected during a 15-month period between October 2009 and December 2010. Patients were included if they were younger than 1 year at the time of presentation. Demographic data, including age, length of hospital stay, second ALTE, and survival, were recorded, along with the prevalence of ECGs and International Classification of Diseases, Ninth Revision, cardiac diagnoses.

RESULTS

There were 2179 patients with an ALTE, with a mean age of 65.7 days old and length of stay of 3.4 days. A total of 947 (43%) of these patients received an ECG. The prevalence of ECG use and cardiac diagnoses were variable among the participating hospitals. Depending on the institution, 0% to 93% of patients had an ECG, and 4% to 39% of patients had an International Classification of Diseases, Ninth Revision, cardiac diagnosis.

CONCLUSIONS

Electrocardiograms are performed in fewer than half of patients with ALTE presenting to children's hospitals. There is wide variation in the prevalence of ECG use as a diagnostic tool for infants presenting with an ALTE.

Dispersion durations of P-wave and QT interval in children with congenital heart disease and pulmonary arterial hypertension

This study aimed to investigate homogeneity disorders of ventricular repolarization and atrial conduction via QT dispersion and P-wave dispersion in children with congenital heart disease (CHD) and pulmonary arterial hypertension (PAH). Three groups of 20 each were generated and involved in this study. The first group included 20 children with both CHD and PAH. The second group consisted of 20 children with CHD but no PAH, and the third group was composed of 20 age- and sex-matched healthy children. Electrocardiographic records were used to determine P-wave, QT, and corrected QT (QTc) dispersions. The pulmonary hypertension group compared with the group having no pulmonary hypertension and the control group showed a significantly longer P-wave dispersion duration (39.10 ± 9.54 vs. 26.30 ± 4.99 ms, p < 0.001; and 24.80 ± 6.94 ms, p < 0.001, respectively) and QT dispersion duration (52.80 ± 15.11 vs. 37.60 ± 6.00 ms, p < 0.001; and 35.00 ± 7.77 ms, p < 0.001, respectively). In addition, the durations of maximum QTc and QTc dispersion were significantly longer in pulmonary hypertension group than in the other two groups. The risk of atrial and ventricular arrhythmia was found to be increased in the patients with both CHD and PAH. Physicians should pay close attention to possible atrial and ventricular arrhythmias during the treatment and follow-up evaluation of these patients.

Rhythm and conduction analysis of patients with acute rheumatic fever

Various rhythm and conduction abnormalities can develop in acute rheumatic fever. This study investigated rhythm and conduction abnormalities in children with acute rheumatic fever using a standard 12-lead electrocardiogram and 24-h rhythm Holter recordings. This multicenter retrospective study, performed between August 2011 and March 2012, enrolled 73 consecutive children with acute rheumatic fever. Standard electrocardiography was used to measure PR and corrected QT intervals. Holter recordings were evaluated for all the patients, and 52 of the patients (71.2 %) had carditis that was either isolated or together with other major criteria. A positive correlation was detected between carditis and the mean PR interval on standard electrocardiography, but this was not significant (p > 0.05). Standard electrocardiography showed a significant positive correlation between PR and corrected QT intervals (p = 0.03; r = 0.55). Standard electrocardiography showed only three patients (4.2 %) with premature contractions, whereas 24-h electrocardiography showed 26 patients (35.6 %) with premature contractions. Carditis was positively correlated with premature contractions (p < 0.01; r = 0.57). One patient with junctional rhythm and one patient with left bundle block were detected by standard electrocardiography. Whereas some patients with carditis exhibited no arrhythmic evidence on standard electrocardiograms, complete atrioventricular block, supraventricular tachycardia, and Mobitz type 1 block were observed on 24-h Holter recordings. A positive correlation also was observed between the presence of premature contractions and serum levels of acute-phase reactants (p = 0.03; r = 0.62). These findings led to the conclusion that rhythm and conduction disorders in acute rheumatic fever are more common than previously thought.

Ventricular repolarisation during exercise challenge occurring late after Kawasaki disease

Exercise testing can highlight repolarisation abnormalities in adults with coronary artery disease. Late after Kawasaki disease (KD), increased QT dispersion (QTd) has been reported on resting ECG in children, but there are no reported studies of QTd during exercise. Our objective was to determine the pattern of QTd response to exercise testing in children late after KD. Twenty-five KD patients without coronary complications, 28 with coronary dilation, and 18 with severe complications were compared with 28 controls. KD patients were 11.6 ± 3.0 years old versus 12.8 ± 2.9 for controls [p = not significant (NS)], and these patients were studied 7.5 ± 3.4 years after the onset of the disease. QT was measured from the onset of QRS to the apex (QTa) and the end (QTe) of T wave. Resting QTd was significantly increased in KD subjects (p < 0.05). The proportion of abnormal QTd was evenly distributed across the three KD groups (29-36%; p = NS). QTd response to exercise was significantly altered in KD, irrespective of resting QTd or coronary sequelae. Abnormal resting- and exercise-induced repolarisation are detectible after KD irrespective of the severity of coronary sequelae.