The Study Of The Clinical Value Of Performing S-ICD Pre-implantation Screening Twice At Different Time

Background: ICD(implantable cardioverter-defibrillator)is one of the most important therapeutic measures to prevent fatal arrhythmias.S-ICD(subcutaneous implantable cardioverter defibrillator)is an ICD system which can be implanted completely subcutaneously.Studies have shown that patients with a primary or secondary prevention ICD indication who do not need pacing or antitachycardia therapy could benefit from S-ICD.Since S-ICD collects surface ECG(electrocardiogram),pre-implantation screening is required to ensure the correct recognition and discharge of S-ICD after implantation.Screening is very important for the safety and efficacy of S-ICD,but no studies have been conducted to compare the screening results of S-ICD at different times.Objective: To explore if the S-ICD pre-implantation screening results for patients with a primary or secondary prevention ICD indication at different times are consistent.Method: From December 2017 to December 2019,80 patients with ICD indications were enrolled and followed-up using manual ECG screening or the S-ICD auto screening in the pacemaker programmer in both erect and supine position.56 patients completed two screening sessions at different times.ECG recordings with pacemaker programmer were achieved over the left and/or right parasternal regions using limb lead electrodes to simulate the S-ICD sensing vectors.Analyze the obtained QRS graphs under the three leads and determine whether each lead passes the screening.If there were at least one lead that satisfy the screening system in both positions,the patient could be a suitable candidate for S-ICD.After 3 months,these patients were rechecked by the same methods to make sure the eligibility for S-ICD.Results: We have studied 80 consecutive patients with ICD indications being recruited from our department of Nanjing First Hospital in this prospective study.75%patients had primary prevention of SCD and 25% of patients had secondary prevention of SCD.56 of them being completed the follow-up at 3 months later.Overall,the eligible patients at first time and at 3 months follow-up satisfied the complete consistency check(p=1.000,> 0.05).Furthermore,the consistency degree of eligible patients at first time and at 3 months follow-up(Kappa index)was 0.347(p=0.09,< 0.05).The results of 8 patients are inconsistent at two times,while the results of 48 patients are consistent at two screening times.The proportion of the patients with inconsistent results at different times of screening was 14.3%.Conclusion: 1.The results of 14.3 percent of patients with ICD implantation indications had inconsistent results from the two screenings,suggesting that the screening results may change.2.In 85.7% of patients,the results of two screening tests were consistent,the results of S-ICD screening could be considered trustworthy.3.We believe it is meaningful to multiple screening at different time points.Patients with long-term stable ECG morphology are more suitable for S-ICD.