Premature ventricular contraction burden measured by an insertable cardiac monitor and the incidence of ventricular tachycardia and fibrillation

Abstract Background Insertable cardiac monitors (ICM) have the capability to continuously monitor premature ventricular contraction (PVC) burden over time [1] as well as detect ventricular tachycardia and fibrillation (VT/VF). Objective We investigated the association of PVC burden with incidence of VT/VF in a large real-world cohort of patients implanted with ICMs. Methods Patients implanted with an ICM for various reasons for monitoring and PVC detection turned on were included from the ICM manufacturer's de-identified data warehouse. Patients were included if they had at least 90 days of PVC burden follow-up. Tachycardia episodes that were detected by the ICM were first classified as VT/VF, SVT, or oversensing using an artificial intelligence (AI) model that was pre-trained using over 60,000 manually adjudicated ICM detected tachycardia episodes. If the AI model output probability for VT/VF was greater than 0.2, then those episodes were manually adjudicated for incidence of non-induced spontaneous VT/VF. The PVC burden trends recorded by the device were divided into 4 mutually exclusive patient groups: (1) 0% PVC burden on all days, (2) 1-4% PVC burden on ≥1 day, (3) 5-9% PVC burden on ≥1 day, and (4) >10% PVC on ≥1 day. The incidence rate of spontaneous VT/VF was compared between the PVC burden patient groups using a Generalized Estimating Equations model with negative binomial distribution. Time to first spontaneous VT/VF occurrence after the first day of occurrence of PVC burden for the respective PVC burden groups were estimated using Kaplan-Meier analysis and the groups were compared using the Cox proportional hazards model. Results A total of 5,521 patients were included in the analysis. Patients had an average age of 69±15 years and 49.8% being males. There was a total of 33,393 tachycardia episodes from 2,641 patients that were detected by the ICM. After AI model probability-based adjudications, 691 spontaneous VT/VF episodes were identified from 277 patients. Patients with ≥1 day of PVC burden of 1-4%, 5-9%, and ≥10% were associated with 2.9, 7.3, and 7.8 times increased incidence rate of VT/VF episodes during follow-up period relative to patients with 0% PVC burden on all days of follow-up (Figure A). Kaplan Meier curves for incidence of first spontaneous VT/VF episode for the four groups following occurrence of the first day of qualifying PVC burden for the respective groups are shown in figure B. Patients with a day of PVC burden ≥10% were 3.5 times more likely to develop VT/VF in the future compared to patients with 0% PVC burden on all days. Conclusion Days with high PVC burden, as detected by an ICM with continuous PVC detection capability, were associated with increased risk of VT/VF events in a group of real-world patients implanted with ICMs. PVC burden measured by ICMs may be a risk stratification tool for further investigation to prevent sudden cardiac arrest.