Comparison of initial detection and redetection of ventricular fibrillation in a transvenous defibrillator system with automatic gain control
Key result
Postshock redetection of ventricular fibrillation took a mean of 4.5 seconds compared to 5.5 seconds for initial detection (p=NS), though abnormal delays occurred in 18% of patients.
Why the study?
Does the time required for redetection of ventricular fibrillation after an unsuccessful shock differ from initial detection time in patients with transvenous ICD systems?
Population
n=22 patients undergoing induced ventricular fibrillation testing with an implantable…
Comparison
Postshock redetection of ventricular fibrillation vs Initial detection of ventricular fibrillation
Design
Cohort
Authors
Discussion
Loading...
Member takes
Implication
Delayed postshock VF redetection occurs in 18% of patients; leaves open whether routine subthreshold testing improves safety with transvenous ICDs.
Study Design
Type
Observational (n=22)
Structured PICO
Does the time required for redetection of ventricular fibrillation after an unsuccessful shock differ from initial detection time in patients with transvenous ICD systems?
P
Population
22 patients undergoing induced ventricular fibrillation to evaluate postshock redetection times.
E
Exposure
Postshock redetection of ventricular fibrillation (after an unsuccessful/subthreshold first shock)
C
Comparator
Initial detection of ventricular fibrillation
O
Outcome
Time required for detection and redetection of ventricular fibrillation (estimated by subtracting capacitor charge time from total event time)surrogate
Main Result
Absolute Event Rate: 4.5% vs 5.5%
p-value: p=NS
Redetection of ventricular fibrillation after a subthreshold shock can be significantly delayed in a subset of patients, suggesting that routine device testing with intentional subthreshold shocks is necessary to verify postshock sensing.
Cite This Study
Berul et al. (1995) conducted an observational in Ventricular fibrillation (n=22). Postshock redetection of ventricular fibrillation vs. Initial detection was evaluated on Time required for detection of ventricular fibrillation (seconds) (p=NS). Postshock redetection of ventricular fibrillation took a mean of 4.5 seconds compared to 5.5 seconds for initial detection (p=NS), though abnormal delays occurred in 18% of patients.