[Relationship between mitral valve prolapse and arrhythmogenic right ventricular disease].
OBJECTIVE
To evaluate some features of ventricular arrhythmias in patients with mitral valve prolapse.


METHODS
We studied 25 patients (female: 19; mean age: 37 +/- 13 years) with ventricular arrhythmias, mitral valve prolapse and normal ventricular function. All patients underwent a 24h Holter and high resolution ECG (HRECG). The Qtc intervals were measured in lead II (normal < 0.44 s). In order to define the possible origin of the ventricular focus, the morphology of the ectopic beats were analysed in leads I, II, aVF, V1 using the following criteria: 1) LBBB morphology with left axis deviation in the frontal plane (FP): origin at the inflow tract of the right ventricle (RV); 2) LBBB morphology with right axis deviation in the FP: origin at the outflow tract of the RV; 3) RBBB morphology with left axis deviation in the FP: origin at the posterior region of the left ventricle (LV). RBBB morphology with right axis deviation in the FP: origin at the anterior region of the LV.


RESULTS
Twenty three (92%) patients showed > 720 isolated ventricular ectopic beats/24 h. Paired ventricular response was detected in 18 (72%) patients and non-sustained VT in 15 (60%). HRECG was positive in six (24%) patients and Qtc interval was prolonged in 13 (52%). RV was the site of origin of the ventricular ectopic beats in 85% of the patients (outflow: 85%; inflow: 15%). Only five (20%) patients had arrhythmias from the LV.


CONCLUSIONS
There was a high incidence of ventricular arrhythmias with a low incidence of positive HRECG tests, suggesting that the mechanisms of the arrhythmias do not correlate with slow intramyocardial conduction. It was noted a strong association between mitral valve prolapse, arrhythmogenic right ventricular disease and Qtc prolongation. It is possible that in some of this patients the finding could represent a global myocardial disease.
Costa
A M
AM
Hospital Pró-Cardíaco/Pró-Ritmo-Rio de Janeiro.
Maia
I G
IG
Cruz Filho
F
F
Fagundes
M L
ML
Sá
R
R
Alves
P
P
D000293:Adolescent; D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D001145:Arrhythmias, Cardiac / Q000150:complications* / Q000000981:diagnostic imaging; D004562:Electrocardiography; D004594:Electrophysiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008945:Mitral Valve Prolapse / Q000150:complications* / Q000000981:diagnostic imaging; D011446:Prospective Studies; D014463:Ultrasonography; D018497:Ventricular Dysfunction, Right / Q000150:complications* / Q000000981:diagnostic imaging
Associação entre prolapso valvar mitral e doença ventricular direita arritmogênica.