The frequency of rhythm and conduction abnormalities and benefits of 24-hour Holter electrocardiogram on detecting these abnormalities in patients with acute rheumatic fever.

INTRODUCTION: During the acute phase of acute rheumatic fever (ARF), cardiac arrhythmias and conduction disorders may occur. Standard electrocardiogram (ECG) may be insufficient in the cases of possible paroxysmal rhythm or conduction abnormalities. The aim of this study is to evaluate arrhythmias and conduction disorders and benefits of 24-hour Holter ECG on detecting these disorders in children with ARF.
METHODS: Two hundred and ten patients who were diagnosed with ARF during a four-year period, were retrospectively analyzed. Demographic characteristics, clinical, laboratory, and echocardiographic findings of the patients were evaluated. Standard ECG and 24-hour Holter analysis were revealed.
RESULTS: First (47.8%), second (6.9%) and third degree (4.3%) atrioventricular (AV) blocks, bundle branch blocks (9.8%), intermittent pre-excitation (1.1%), accelerated nodal rhythm (15.2%), supraventricular (10.9%) and ventricular premature contractions (8.7%), as well as supraventricular (3.3%) and ventricular tachycardia (1.1%) were detected with 24-hour Holter ECG. Frequency of both rhythm and conduction abnormalities were detected higher with Holter ECG than 12-lead ECG, and this was statistically significant (p<0.05). Second degree type II AV block and non-sustained supraventricular tachycardia as well as intermittent complete AV block were detected on 24-hour Holter analysis in patients with normal initial standard ECG.
DISCUSSION AND CONCLUSION: The incidence of rhythm and conduction abnormalities are higher than traditionally known. 24-hour Holter ECG is very helpful to detect especially paroxysmal abnormalities and to determine the more exact incidence of rhythm and conduction abnormalities in patients with ARF. For this reason, we suggest a routine 24-hour Holter ECG analysis in tertiary pediatric heart centers for patients with ARF.