Usefulness of patient’s history and non-invasive electrocardiographic parameters in prediction of ajmaline test results in patients with suspected Brugada syndrome

Abstract

IntroductionThe aim of the work was to assess the usefulness of patient's history and non-invasive electrocardiographic parameters in the prediction of ajmaline test results in patients with suspected Brugada syndrome.Material and methodsThe study involved a group of 59 patients (37 men) at average age of 31.6 ±12.2 years with suspected concealed form of Brugada syndrome. Pharmacological provocation with intravenous ajmaline administration was performed. The patients were divided into two groups depending on ajmaline test results. Individual and total predictive value for ajmaline test was based on the analysis of medical anamnesis and non-invasive electrocardiographic examination.ResultsThe analysis carried out within the work indicated a special predictive value of 2 parameters which constituted the study inclusion criteria – family history of Brugada syndrome (28.6% vs. 3.8%; p = 0.0477) and occurrence of saddleback electrocardiographic changes in ECG curve (42.9% vs. 0.0%; p = 0.0002). Non-invasive electrocardiographic parameters which showed significant predictive value for ajmaline test were as follows: dispersion of QTc interval (prior to the provocation test 54.43 ±24.77 ms vs. 32.70 ±12.98 ms; p = 0.0005 and during daytime activity 46.81 ±27.16 ms vs. 32.07 ±13.19 ms; p = 0.0198), corrected QT intervals, Tpeak-Tend intervals in particular leads, QTpeak intervals, dispersion of Tpeak-Tend interval assessed from precordial leads (V1–V6) (42.86 ±13.80 ms vs. 26.54 ±11.70 ms; p = 0.001) and J-point elevation in V2 and V3 leads.ConclusionsBoth interview and non-invasive electrocardiographic parameters which reflect cardiomyocyte repolarization disorders are of high predictive value in anticipating ajmaline pharmacological provocation results in patients with suspected Brugada syndrome.

ST-segment changes in high-resolution body surface potential maps measured during exercise to assess myocardial ischemia: a pilot study

“…It is estimated that in European countries heart diseases are responsible for around 40% of cases of death before age 74 years [ 1 , 2 ]. The high mortality rate among men and women [ 3 – 5 ] justifies the need to search for new diagnostic methods which ensure high sensitivity and specificity in detection of myocardial ischemia.…”

Some Clinical Advances on Brugada Syndrome

“…The commonly used drugs are Ajmaline and Flecainide in foreign countries and Propafenone in the domestic [5]. Now brief introductions are as follows: (A)Ajmaline: Considering the research results so far, Uzieblo-Zyczkowsk, et al [6] applied Ajmaline because of its highest sensitivity and specificity as well as the drastical reduce of complications in the same time test. Another reason to choose Ajmaline was its short half-life (near 10min), which was convenient for a short time post-test observation on patients in hospital not more than 1 day.…”

“…Recording for a long time (10~90min), the rate of type 1 ECG pattern has a progressive increases. However, there are some inadequacies in drug provocation test using class 1 antiarrhythmic specific drugs [6], for example, they can cause fatal arrhythmias induced by their arrhythmogenic effects, meanwhile, we should obtain the consent of patients of concealed BrS before the test. The indications about ending drug test [4] are: ①the appearance type 1 Brugada ECG; ② ST segment increase≥2mm in type 2 ECG pattern; ③the occurrence of ventricular premature beats or other arrhythmia; ④QRS widening ≥ 130% of the baseline.…”