Arrhythmic Storm

Clinical Case

Saverio Iacopino, MD, FACC, FESC

ü ICD have become the main therapeutic tool for patients with life-threatening VE arrhythmias

ü Some patients receive multiple appropriate shocks during a short period due to arrhythmic storm

ü The arrhythmic episodes was successfully controlled in the majority of patients with antiarrhythmic drug therapy

Background

ü Men, 51 years old with single chamber PM for paroxistical AV block

ü Syncope and sustained VT with RBBB morphology and superior axis deviation at a rate of 150 bpm

Case History

ü Coronary risk factors ü Family history of early CAD ü Hypercholesterolemia ü Continued heavy smoking

ü ECHO: dilated cardiomyopathy (EF=45%)

ü No angiographic coronary artery stenosis

Case History

ü EP study

ü Easily inducible symptomatic sustained monomorphic VT with RBBB, superior axis, CL 350 msec, terminated by overdrive pacing

ü Patient then underwent implantation of an single chamber ICD

Case History

ü  Tachycardia zone ü  For rates between 150-200 bpm

ü  ATP

ü  Low energy cardioversion

ICD Therapy

ü VF zone ü  For rates exceeding 200 bpm

ü Beta-blockers ü ACE-Inhibitor ü Diuretics ü Amiodarone

Drug Therapy

ü At first month ü  6 episodes of VT were recorded and were ü  terminated by ATP schemes

Follow-up

ATP Therapy

ü At six month ü  Patient was admitted to our hospital in a state of

panic because of multiple shocks deliveries by the device

Follow-up

ü Myocardial ischemia, electrolyte disturbances or other triggering factors as an etiology of the arrhythmic storm could not be supported

ü  Intravenous amiodarone and mexiletine were initiated

ü The arrhythmic storm subsided two days after

Follow-up

ü  58 tachyarrhythmic episodes were recorded in the tachycardia zone

ü  41 were terminated by ATP schemes

ü  3 episodes were accelerated by ATP and entered in VF zone and terminated by low energy shock

ü  10 fast VT episodes were detected in VF zone and terminated by low energy shocks

ü  3 episodes exhibited immediate reinitiation and thus required maximal energy shocks

ICD Therapy

ü  The patient reported dizziness but not syncope just before shock delivery

…. and we proposed RFA of the slow VT with the probability of modification or even elimination of the fast VT

Basal EKG

Inducible VT

VT Induced

Conventional LV Mapping

Lateral Postero-Lateral

Posterior Postero-Septal

Lateral

Left Lateral Region Mapping Early Activation During VT

Concealed entrainment from ablation site Inducible VT

Concealed entrainment from ablation site Inducible VT

450 mS

VT termination during RF

RF on

VT termination during RF

stimulation protocol with up to three extra stimuli from the right

ventricle apex

in basal conditions

and after isoprenaline infusion

ü RF current (7 applications) was applied for 60 seconds at maximum power output of 50 W and temperature limit of 50 °C with the 4-mm closed Cooled-tip catheter

ü The targets considered are the following:

ü discontinuation of VT

ü persistency of this result for 30 minutes in basal conditions and with the infusion of the isoprenaline

Methods

Follow-up

ü During a follow-up of 12 months without any antiarrhythmic drug, no VT relapse has been documented

ü Holter ECG executed at one, three and six months later, no NSVT has been documented

Conclusion ü Patients who experience multiple ICD shock

therapies require urgent evaluation and management

ü Antiarrhythmic drugs, alone or in combination, may be effective in decreasing the frequency of recurrences of VE arrhythmias or ICD shocks

ü RFA may be a curative approach