Prevalence of arrhythmias on 24-h ambulatory Holter electrocardiogram monitoring in LASUTH: A report on 414 patients

Background: The 24-h ambulatory holter electrocardiogram (ECG) monitor is particularly able to document bradyarrhythmic or tachyarrhythmic episodes which might be missed on normal 12-lead resting ECG recordings. It is, therefore, particularly useful in evaluating patients with symptomatic or asymptomatic paroxysmal tachy/bradyarrhythmias and is also useful in monitoring patients on antiarrhythmic therapy. The present study was aimed at presenting our findings on the prevalence of arrhythmias on the 24-h Holter ECG of a relatively large cohort of patients referred to our cardiac facility, over the last few years. Methods: This was a retrospective audit of prevalence of cardiac arrhythmias among 414 patients consisting of 184 males and 230 females who were referred for 24-h Holter ambulatory ECG monitoring in LASUTH, Ikeja, Nigeria, between January 2014 and June 2019. Their age ranged from 13 to 95 years with a mean age of 50.42 ± 16.29. Results: The most common single indications for Holter monitoring in these patients were unexplained palpitation and presyncope/syncope. Ventricular extrasystole was the most common arrhythmias found on Holter ECG. Only 14 out of the 414 patients had Holter ECG evidence of nonsustained ventricular tachycardia (VT). There was no significant difference in the prevalence of cardiac arrhythmias in males compared to their female counterparts. However, elderly patients of 65 years and above had significantly higher prevalence of cardiac arrhythmias when compared to their younger counterparts (χ2 = 54.46, P < 0.01). Conclusion: The study suggests that palpitation is the most common reason for referral of patients for 24-h ambulatory Holter ECG test. It also showed that ventricular extrasystoles are the most common arrhythmias on the 24-h Holter ECG. In addition, it reinforces the fact that nonsustained VT is uncommon among the Nigerian patients and that elderly patients were more likely to have cardiac arrhythmias compared to their younger counterparts.