Effects of the location of myocardial infarction on the spectral characteristics of ventricular fibrillation.
BACKGROUND
The location of the myocardial infarction (MI) might modify the spectral characteristics of ventricular fibrillation (VF) in humans.


OBJECTIVE
To evaluate the effect of the location of the infarcted area on the spectral parameters of VF.


METHODS
Patients with chronic MI (29 anterior, 32 inferior) and induced VF during cardioverter defibrillator implant were retrospectively studied. Dominant frequency (f(d)), organization index (OI), and power of the harmonic peaks were calculated in the device-stored electrograms (EGM) during sinus rhythm (SR) and VF.


RESULTS
The f(d) of the VF was not affected by the left ventricular ejection fraction (LVEF) or the MI location (anterior: 4.54 +/- 0.74 Hz, inferior: 4.77 +/- 0.48 Hz, n.s.). The OI was also similar in both groups. However, in patients with inferior MIs, normalized peak power at f(d) was higher (118.3 +/- 18.5 vs 100.6 +/- 28.2, P < 0.01) and the normalized peak power of the harmonics was lower than in the anterior MI group. The analysis of EGM during SR showed similar results. The size of the necrotic area and its distance to the recording electrode might partially explain these results.


CONCLUSIONS
In our series, the spectral characteristics of the EGMs during VF showed significant differences depending on the MI localization. A higher fraction of energy (in the low-frequency region) was seen in inferior MIs, whereas the peak power at the harmonics increased in anterior MIs. A similar effect was seen during SR and VF, suggesting that it is caused by local electrophysiology abnormalities induced by the MI rather than by different intrinsic characteristics of the VF.
Arrhythmia Unit, Hospital Universitario Virgen de la Arrixaca de Murcia, Murcia, Spain.
Juan J
JJ
Sánchez-Muñoz
José L
JL
Rojo-Alvarez
Arcadio
A
García-Alberola
Estrella
E
Everss
Jesús
J
Requena-Carrión
Mercedes
M
Ortiz
Felipe
F
Alonso-Atienza
Mariano
M
Valdés-Chavarri
D000368:Aged; D018780:Body Surface Potential Mapping / Q000379:methods*; D003198:Computer Simulation; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008955:Models, Cardiovascular; D009203:Myocardial Infarction / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology*; D014693:Ventricular Fibrillation / Q000150:complications / Q000503:physiopathology*