Empiric Trial

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1 Introduction
2 Empiric Arm Programming
3 Results
4 Conclusions
5 References

Introduction

The hypothesis of the Empiric Trial was that a empiric set of VT/VF programmable settings is at least as effective as physician tailored choices as measured by the shock related morbidity of ICD therapy. The endpoints were the proportion of true VT/VF episodes that were shocked and the Proportion of true SVT episodes that were inappropriately shocked. The settings programmed in the Empiric arm are listed below

Empiric Arm Programming

Zone	Detection	Interval/Rate	Beats to Detect	Therapies
VF	On	300 ms (>200 bpm)	18 of 24	30J x 6
FVT	Via VF	240ms (201 - 250 bpm)	NA	Burst³, 30 J x 5
VT	On	>400ms (<150-200 bpm)	16	Burst¹, Burst², Ramp¹, 20J, 30 J x 3

PR Logic® Detection On: AF/Afl
Sinus Tach (1:1 VT-ST = 66%)
SVT Limit = 300 ms
Burst¹, ATP: 8 intervals, R-S1 = 88%, 20 ms decrement
Burst², ATP: 8 intervals, R-S1 = 88%, 20 ms decrement
Ramp¹, ATP: 8 intervals, R-S1 = 81%, 10 ms decrement
Burst³, ATP: 8 intervals, R-S1 = 88%, 10 ms decrement

Results

The adjusted percentages of VT/VF that were shocked was 22.3% in the Empiric Group and 28.7% in the physician tailored group. The percentage of supraventricular tachycardia or other non-VT/VF event episodes that resulted in a shock were was 11.9% vs. 26.1% in the Empiric arm compared to the Tailored arm. There were no significant differences in total mortality, syncope, emergency room visits, or unscheduled outpatient visits. Unscheduled hospitalizations occurred significantly less often (p = 0.001) in the Empiric arm.

Conclusions

Standardized empiric ICD programming for VT/VF settings is at least as effective as patient-specific, physician-tailored programming, as measured by many clinical outcomes.