Inducibility of ventricular arrhythmias in Chronic Chagas disease
predicted by clinical scores.
Abstract
BACKGROUND Electrophysiologic Study (EPS) is a diagnostic tool that can
further evaluate patients prone to arrhythmic death.OBJECTIVE To shed
light on the causes of death in Chagas disease, specially on regards of
importance of the VT induction and chances of death, as evaluated by
Rassi clinical score. METHODS We evaluated data from 153 patients with
Chagas disease from the electrophysiology laboratory from a tertiary
center between January of 2011 and January 2013. All patients were
evaluated with 1, 2, 3 or 4 ventricular extra-stimuli followed by runs
of 10 beats fast ventricular stimulation. If VT or VF is inducible the
patients are referred to ICD implant or VT ablation. RESULTS Of a total
of 153 patients, 48% were male, mean age 58 ±12 years (24 - 84 years).
As for risk of death according to the clinical score, 32% were
evaluated as low risk, 35,4% intermediate, 32,6% high risk. NSVT on 24
hour Holter (p=0,009), stimulation on EPS (p<0,001), lower
VEFE (p<0,01), cardiomegaly (p<0,001) and high risk
on Rassi score (p<0,001) where the more associated variables
to ventricular tachyarrithmias. CONCLUSIONS Clinical score is an
interesting tool to further stratify patients in higher risk for VT
induction during EPS, which is also a marker of higher risk of sudden
cardiac death. Some characteristics as Non sustained VT, Pulmonary
congestion, cardiomegaly and low voltage QRS were the most relevant
determinants for inducible VT on EPS. The duration of NSVT is also
important for VT induction in EPS.