TWA Identifier for Cardiac Risk Self-Monitoring during Hemodialysis: A Case Report

Abstract

Rate of sudden cardiac death (SCD) is increased in hemodialysis (HD) patients. Cardiac risk can be evaluated in terms of electrocardiographic (ECG) T-wave alternans (TWA). Aim of the present study was to propose TWA Identifier as a software application for cardiac risk self-monitoring based on the TWA index, and to test it on a patient while performing a HD session. TWA Identifier can be installed on any portable device and may analyze real-time ECG data acquired by wearable sensors. Core of TWA Identifier is the well-established heart-rate adaptive match filter method for TWA identification. TWA Identifier quantified TWA from a continuous 24-hours ECG acquired using a wearable Holter ECG recorder in a HD patient during a HD day. The recording was divided into macro-time periods, one prior, one contemporary and two following the HD session. On average, TWA values were higher than normal, ranged from 35 µV to 78 µV, and were particularly high during the HD session, while decreased afterwards. Thus, the HD patient was at increased SCD risk, especially during the treatment. In conclusion, TWA Identifier represents a useful tool for real-time cardiac risk self-monitoring during HD.