title: Rotor stability separates sustained ventricular fibrillation from self-terminating episodes in humans.
abstract: OBJECTIVE
  This study mapped human ventricular fibrillation (VF) to define mechanistic differences between episodes requiring defibrillation versus those that spontaneously terminate.
  
  
  BACKGROUND
  VF is a leading cause of mortality; yet, episodes may also self-terminate. We hypothesized that the initial maintenance of human VF is dependent upon the formation and stability of VF rotors.
  
  
  METHODS
  We enrolled 26 consecutive patients (age 64 ± 10 years, n = 13 with left ventricular dysfunction) during ablation procedures for ventricular arrhythmias, using 64-electrode basket catheters in both ventricles to map VF prior to prompt defibrillation per the institutional review board-approved protocol. A total of 52 inductions were attempted, and 36 VF episodes were observed. Phase analysis was applied to identify biventricular rotors in the first 10 s or until VF terminated, whichever came first (11.4 ± 2.9 s to defibrillator charging).
  
  
  RESULTS
  Rotors were present in 16 of 19 patients with VF and in all patients with sustained VF. Sustained, but not self-limiting VF, was characterized by greater rotor stability: 1) rotors were present in 68 ± 17% of cycles in sustained VF versus 11 ± 18% of cycles in self-limiting VF (p < 0.001); and 2) maximum continuous rotations were greater in sustained (17 ± 11, range 7 to 48) versus self-limiting VF (1.1 ± 1.4, range 0 to 4, p < 0.001). Additionally, biventricular rotor locations in sustained VF were conserved across multiple inductions (7 of 7 patients, p = 0.025).
  
  
  CONCLUSIONS
  In patients with and without structural heart disease, the formation of stable rotors identifies individuals whose VF requires defibrillation from those in whom VF spontaneously self-terminates. Future work should define the mechanisms that stabilize rotors and evaluate whether rotor modulation may reduce subsequent VF risk.
authors.affiliation: University of California San Diego, San Diego, California; Veterans Affairs San Diego Healthcare System, San Diego, California. Electronic address: dkrummen@ucsd.edu.
authors.forename: David E
authors.initials: DE
authors.lastname: Krummen
authors.affiliation: University of California San Diego, San Diego, California; Veterans Affairs San Diego Healthcare System, San Diego, California.
authors.forename: Justin
authors.initials: J
authors.lastname: Hayase
authors.affiliation: University of California San Diego, San Diego, California; Veterans Affairs San Diego Healthcare System, San Diego, California.
authors.forename: David J
authors.initials: DJ
authors.lastname: Morris
authors.affiliation: University of California San Diego, San Diego, California; Veterans Affairs San Diego Healthcare System, San Diego, California.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Ho
authors.affiliation: Veterans Affairs San Diego Healthcare System, San Diego, California.
authors.forename: Miriam R
authors.initials: MR
authors.lastname: Smetak
authors.affiliation: Veterans Affairs San Diego Healthcare System, San Diego, California.
authors.forename: Paul
authors.initials: P
authors.lastname: Clopton
authors.affiliation: University of California San Diego, San Diego, California.
authors.forename: Wouter-Jan
authors.initials: WJ
authors.lastname: Rappel
authors.affiliation: University of California San Diego, San Diego, California; Veterans Affairs San Diego Healthcare System, San Diego, California.
authors.forename: Sanjiv M
authors.initials: SM
authors.lastname: Narayan
mesh_terms: D000368:Aged; D018780:Body Surface Potential Mapping / Q000379:methods / Q000592:standards*; D006328:Cardiac Catheterization / Q000379:methods / Q000592:standards*; D022062:Electrophysiologic Techniques, Cardiac / Q000379:methods / Q000592:standards*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D013997:Time Factors; D014693:Ventricular Fibrillation / Q000175:diagnosis* / Q000503:physiopathology*
keywords: arrhythmia mechanisms; electrical rotors; electrophysiology; ventricular fibrillation