[Radioisotopic mapping of the arrhythmogenic focus in patients with chronic chagasic cardiomyopathy and sustained ventricular tachycardia].
OBJECTIVE
To localize the site of the origin of sustained ventricular tachycardia in chronic chagasic cardiomyopathy patients refractory to antiarrhythmic therapy by radionuclide angiography techniques.


METHODS
Five patients underwent radionuclide angiography by intravenous administration of 25mCi 99mTc. The images were obtained in sinus rhythm and during sustained ventricular tachycardia induced in the electrophysiologic laboratory for endocardial mapping. Amplitude and phase images were obtained resulting in a contraction wave synchronic to ventricular dispolarization.


RESULTS
All patients had haemodynamic stability during the arrhythmia. One patient had incessant ventricular tachycardia. Mean ejection fraction was 0.38. In 4 patients the site of the origin of ventricular tachycardia was posterior and in one it was localized in the interventricular septum. There was identity in the site of the origin of ventricular tachycardia obtained by endocardial mapping or radionuclide angiography in all patients. The therapy was chemical ablation in 3 patients, surgical aneurysmectomy in one and pharmacologic therapy in the last patient.


CONCLUSIONS
The site of the origin of ventricular tachycardia can be estimated by analyzing the contraction wave obtained by radionuclide angiography techniques in patients with hemodynamic stable sustained ventricular tachycardia.
de Paola
A A
AA
Escola Paulista de Medicina, São Paulo.
Balbão
C E
CE
Castiglioni
M L
ML
Barbieri
A
A
Mendonça
A
A
Netto
O S
OS
Guiguer Júnior
N
N
Vattimo
A C
AC
Souza
I A
IA
Portugal
O P
OP
D000328:Adult; D000368:Aged; D002598:Chagas Cardiomyopathy / Q000000981:diagnostic imaging*; D002908:Chronic Disease; D004594:Electrophysiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011875:Radionuclide Angiography; D017180:Tachycardia, Ventricular / Q000000981:diagnostic imaging*
Mapeamento radioisotópico do foco arritmogênico em portadores de cardiopatia chagásica crônica e taquicardia ventricular sustentada.