Abstract
Funding Acknowledgements
Type of funding sources: None.
OnBehalf
The NIPS-ICD Investigators
Background
Implantable cardioverter-defibrillator (ICD) offers an opportunity to examine vulnerability to ventricular tachycardia (VT) or ventricular fibrillation (VF) by performing non-invasive programmed ventricular stimulation (NIPS). Whether NIPS can predict mortality in patients with primary prevention ICD, has not yet been examined.
Purpose
To examine a long-term predictive value of NIPS for identification of patients at increased risk of death during follow up.
Methods
The study group consisted of consecutive 41 patients with ICD implanted for primary prevention of sudden cardiac death, included in the prospective NIPS-ICD study (ClinicalTrials ID: NCT02373306) (34 males, age 64 ± 11 years). The patients underwent NIPS using the protocol up to three premature extrastimuli at 600, 500 and 400ms drive cycle lengths. The end-point of NIPS was induction of sustained VT or VF or completion of the protocol.
Results
At baseline NIPS, VT/VF was induced in 8 (20%) patients. After 5 year follow up mortality rate was significantly higher in patients who had VT/VF induced at NIPS vs no VT/VF at NIPS (38% vs 12%, p = 0.04). The difference in mortality was most remarkable at 3 (38% vs 3%, p = 0.001) and 4 years (38% vs 6%, p = 0.007). The NIPS-induced VT/VF had a sensitivity of 37.5%, specificity of 88%, positive predictive value of 43% and negative predictive value of 85% for occurrence of death during follow up. An occurrence of secondary composite endpoint consisting of VT/VF recurrence or death was also most frequent in NIPS-inducible group (75% vs 24%, p = 0.037). In a multivariate Cox-Proportional Hazard model induction of VT/VF at NIPS along with age≥65, and treatment with amiodarone was an independent predictor of the composite endpoint during follow-up
Conclusions
Inducibility of VF/VF during NIPS in patients with primary prevention ICD is associated with higher mortality and higher incidence of composite endpoint consisting of death or VT/VF during a long term observation. Abstract Figure. Kaplan-Meier survival curves