![]() The system reported an average sensitivity of 0.62 to detect a change during an episode of acute decompensation and an average specificity of 0.67 on the blind validation set, when the frequency of alert was four weeks. The system generates an alert when there is a change in the underlying probability distribution of the time series which can be regarded as a surrogate marker of patient stability.The system's performance is evaluated using dual-site longitudinal data collected from 104 HF patients over 12-24 months. To reduce hospitalization, this paper proposes a novel home telemonitoring system for an early warning of acute decompensation in patients with chronic stable New York Heart Association class II-IV HF.It is based on deriving nocturnal respiratory related time series using a noncontact radio-wave bio-motion sensor. Hospitalization due to heart failure (HF) continues to be a major clinical and economic challenge. Our findings could have an important implication in future studies of RF cardiac ablation, in particular, in choosing the most suitable method to model the thermal effect of circulating blood. Considering the aspects of lesion size and maximum temperature reached in blood and tissue, Method 2 seems to be the most suitable alternative to Method 4 in order to reduce the computational complexity. The other three methods predicted lesion depth values similar to those of the reference method (differences smaller than 1 mm), regardless of ablation mode and blood flow conditions. Only Method 4 provided a realistic blood temperature distribution. Method 4) included blood motion and was considered to be a reference method for comparison purposes. Three of them considered convective coefficients at the electrode-blood and tissue-blood interfaces to model blood flow: 1) without including blood as a part of the domain 2) constant electrical conductivity of blood and 3) temperature-dependent electrical conductivity of blood (+2%/☌). ![]() Four methods of modeling the effect of circulating blood flow on lesion dimensions and temperature distribution were compared. Computational models were built to study the temperature distributions and lesion dimensions created by a nonirrigated electrode by two RF energy delivery protocols (constant voltage and constant temperature) under high and low blood flow conditions. Our aim was to compare the different methods of modeling the effect of circulating blood flow on the thermal lesion dimensions created by radio frequency (RF) cardiac ablation and on the maximum blood temperature.
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