Abstract 4666: Anatomic Substrate as Determinant of Dominant Frequency Dynamics During Human Ventricular Fibrillation

Autor: Karthikeyan Umapathy, Stephane Masse, Elias Sevaptsidis, John Asta, Talha Farid, Elnaz Shokrollahi, Krishnakumar Nair, Heather Ross, Terry Yau, Robert Cusimano, Sridhar Krishnan, Kumaraswamy Nanthakumar
Rok vydání: 2008
Předmět:
Zdroj: Circulation. 118
ISSN: 1524-4539
0009-7322
DOI: 10.1161/circ.118.suppl_18.s_927-c
Popis: Background: Dominant frequency (DF) analysis is a common way of quantitatively studying the spatio-temporal variation of frequency during VF. Areas of high frequencies (e.g. rotors) and low frequencies (e.g. blocks) have been associated with the occurrence and maintenance of VF. However, the relation of these high or low frequency areas to anatomical or physiological substrate remains unclear. Objective: We tested the hypothesis that the Max-Min DF locations in the epicardium during VF are due to anatomical substrate. Methods and Results: We analyzed 33, 4 seconds VF episodes acquired from 6 isolated human hearts using a Langendorff setup. The hearts were received from the heart-transplanted patients with informed consent. Electrode array consisting 112 bipolar electrodes was used to acquire the surface unipolar and bipolar electrograms from the epicardium. DF was computed as the peak frequency of the VF segment from each of electrodes using Welch’s modified periodogram method. From the DF distribution, the regions of max and min frequencies were identified for LV and RV regions. Scar maps were computed for each of the 6 hearts using a previously published method by mapping the amplitude of bipolar electrograms ( shows the match between the max-min DF frequency locations and the scar locations. 50% of max-min DF frequencies locations match the scar locations and in 97% of the matched locations the max-min DF occur at the vicinity of the scar. Conclusion: During human VF, DF dynamics are only partially explained by the anatomical substrate. This suggests that ion channel heterogeneity and dynamic physiological factors may play an important role in determining fibrillation dynamics. Match Between Max-Min DF locations and Scar Locations
Databáze: OpenAIRE
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