Mode of initiation and ablation of ventricular fibrillation storms in patients with ischemic cardiomyopathy.
OBJECTIVE
We report on the initiation of ventricular fibrillation (VF) storm in patients with ischemic cardiomyopathy (ICM) and the results of targeted ablation to treat VF storm.


BACKGROUND
Monomorphic premature ventricular contractions (PVCs) have been shown to initiate VF in patients without structural heart disease.


METHODS
A total of 29 patients with ICM and documented VF initiation were identified. In 21 patients, VF storm was controlled with antiarrhythmic drugs and/or treatment of heart failure. Eight patients with VF (mean 52 +/- 25 episodes) refractory to medical management required ablation. All patients underwent three-dimensional electroanatomical mapping using CARTO (Biosense-Webster Inc., Diamond Bar, California), and PVCs were mapped when present. Scarred areas were identified using voltage mapping.


RESULTS
Monomorphic PVCs initiated VF in all 29 identified patients. Five of eight patients requiring ablation had frequent PVCs that allowed PVC mapping. The earliest activation site was consistently located in the scar border zone. The PVCs were always preceded by a Purkinje-like potential (PLP). Ablation was successfully performed at these sites. In three patients, infrequent PVCs prevented mapping, but PLPs were recorded around the scar border. Ablation targeting these potentials along the scar border was successfully performed. During follow-up (10 +/- 6 months), one patient had a single VF episode and another developed sustained, monomorphic ventricular tachycardia. There was no recurrence of VF storm.


CONCLUSIONS
Ventricular fibrillation in ICM is triggered by monomorphic PVCs originating from the scar border zone with preceding PLPs; targeting these PVCs may prevent VF recurrence. In the absence of PVCs, both substrate mapping and ablation appear to be equally effective.
Marrouche
Nassir F
NF
Section of Cardiovascular Electrophysiology, Department of Cardiology, Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA.
Verma
Atul
A
Wazni
Oussama
O
Schweikert
Robert
R
Martin
David O
DO
Saliba
Walid
W
Kilicaslan
Fethi
F
Cummings
Jennifer
J
Burkhardt
J David
JD
Bhargava
Mandeep
M
Bash
Dianna
D
Brachmann
Johannes
J
Guenther
Jens
J
Hao
Steven
S
Beheiry
Salwa
S
Rossillo
Antonio
A
Raviele
Antonio
A
Themistoclakis
Sakis
S
Natale
Andrea
A
D000368:Aged; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D018780:Body Surface Potential Mapping; D009202:Cardiomyopathies / Q000503:physiopathology / Q000628:therapy*; D017115:Catheter Ablation; D017147:Defibrillators, Implantable; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D005500:Follow-Up Studies; D006329:Heart Conduction System / Q000503:physiopathology / Q000601:surgery; D006333:Heart Failure / Q000503:physiopathology / Q000628:therapy; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000502:physiology; D017202:Myocardial Ischemia / Q000503:physiopathology / Q000628:therapy*; D013318:Stroke Volume / Q000502:physiology; D016896:Treatment Outcome; D014693:Ventricular Fibrillation / Q000503:physiopathology / Q000628:therapy*
D000889:Anti-Arrhythmia Agents