Interventricular mechanical dyssynchrony: a novel marker of cardiac events in Brugada syndrome.
BACKGROUND
Risk stratification in Brugada syndrome is controversial, especially in asymptomatic individuals.


OBJECTIVE
The purpose of this study was to evaluate tissue Doppler echocardiography in risk stratification of Brugada syndrome.


METHODS
Patients with Brugada ECG pattern were enrolled in the study. Left ventricular (LV) preejection period was defined as the time interval between onset of the QRS complex and onset of LV lateral wall systolic wave. Right ventricular (RV) preejection period was defined as the time interval between onset of the QRS complex and onset of RV lateral wall systolic wave. Delay in onset of contraction between RV and LV was defined as RV preejection time - LV preejection time [PET((RV-LV))].


RESULTS
Type 1, 2, and 3 Brugada ECG pattern was found in 30, 56, and 31 patients, respectively. PET((RV-LV)) was significantly greater in type 1 Brugada patients (39.2 +/- 3.2 ms) compared with type 2 (5 +/- 0.3 ms) and 3 (5 +/- 0.4 ms) Brugada patients as well as controls (4.6 +/- 0.3 ms, P <.01 for all comparisons). Among type 1 Brugada patients, PET((RV-LV)) was significantly greater in patients who had previous cardiac events compared with asymptomatic subjects (48.2 +/- 4.3 ms vs 29.5 +/- 3.6 ms, P <.05). In the presence of type 1 Brugada ECG pattern, PET((RV-LV)) > or =40 ms identifies patients likely to have cardiac events, with 85.7% sensitivity and 93.7% specificity.


CONCLUSIONS
PET((RV-LV)) is an important risk indicator for Brugada syndrome.
Babaee Bigi
Mohamad Ali
MA
Cardiology Department, Shiraz University of Medical Sciences, Shiraz, Iran.
Moaref
Ali Reza
AR
Aslani
Amir
A
D000328:Adult; D015415:Biomarkers; D053840:Brugada Syndrome / Q000000981:diagnostic imaging / Q000503:physiopathology*; D016022:Case-Control Studies; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology; D006352:Heart Ventricles / Q000503:physiopathology; D006801:Humans; D008297:Male; D018570:Risk Assessment; D013318:Stroke Volume; D013599:Systole; D014463:Ultrasonography
D015415:Biomarkers