Relationship between Non-sustained Ventricular Tachycardia before Implantation and Appropriate Therapy in Patients with Implantable Cardioverter Defibrillator for Primary Prevention of Sudden Cardiac Death

  Objective  The aim of this study was to explore the relationship between non-sustained ventricular tachycardia (NSVT) recorded by Holter before implantation and appropriate therapy in patients with implantable cardioverter defibrillator (ICD) for primary prevention of sudden cardiac death.

  Methods  A single-center retrospective cohort study was conducted. Consecutive inpatients who received ICD for primary prevention and finished Holter examination from January 2006 to December 2017 in Peking Union Medical College Hospital were enrolled. According to the results of Holter, the patients were divided into the NSVT group and the non-NSVT group. Clinic or telephone follow-ups were conducted until August 2018; the follow-up events included all-cause death, shock therapy, and anti-tachycardia pacing (ATP).

  Results  Sixty patients meeting the inclusive and exclusive criteria were enrolled in this study. Median follow-up of all patients was 37 (14-61) months. Kaplan-Meier curve and Log-Rank test showed that there was no significant difference in mortality between the NSVT and the non-NSVT group (P=0.108), while the NSVT group had a significantly higher rate of appropriate therapy (P=0.033). Multivariate competitive risk regression analysis indicated that NSVT and left ventricular ejection fraction were independently correlated with the ICD appropriate therapy (NSVT: HR=5.099, 95% CI:1.399-18.588, P=0.014; left ventricular ejection fraction: HR=1.077, 95% CI:1.013-1.145, P=0.018).

  Conclusion  NSVT in patients with ICD implantation for primary prevention suggests an increased risk of receiving appropriate therapy.