Impact of Indoor Environment on Path Loss in Body Area Networks

In this paper the influence of an example indoor environment on narrowband radio channel path loss for body area networks operating around 2.4 GHz is investigated using computer simulations and on-site measurements. In contrast to other similar studies, the simulation model included both a numerical human body phantom and its environment—room walls, floor and ceiling. As an example, radio signal attenuation between two different configurations of transceivers with dipole antennas placed in a direct vicinity of a human body (on-body scenario) is analyzed by computer simulations for several types of reflecting environments. In the analyzed case the propagation environments comprised a human body and office room walls. As a reference environment for comparison, free space with only a conducting ground plane, modelling a steel mesh reinforced concrete floor, was chosen. The transmitting and receiving antennas were placed in two on-body configurations chest–back and chest–arm. Path loss vs. frequency simulation results obtained using Finite Difference Time Domain (FDTD) method and a multi-tissue anthropomorphic phantom were compared to results of measurements taken with a vector network analyzer with a human subject located in an average-size empty cuboidal office room. A comparison of path loss values in different environments variants gives some qualitative and quantitative insight into the adequacy of simplified indoor environment model for the indoor body area network channel representation

Wireless Capsule Endoscope Localization with Phase Detection Algorithm and Simplified Human Body Model

Wireless endoscopic capsules can visualize the inside of the digestive tract for the purpose of gastrointestinal diseases diagnose. In order to implement the appropriate treatment method, the transmitted picture should be followed by the information on the location of the endoscope. The article presents the method of localization of endoscopic capsules with wireless transmitter based on the detection of phase difference of signals in the receiver located on patients body. The proposed method uses simplified human body models that can change their dielectric properties to improve the location of the capsule endoscope

Inertial sensors integrated with clothing to localize people inside buildings

This article presents a wearable system that localizes people in the indoor environment, using data from inertial sensors. The sensors measure the parameters of human motion, tracking the movements of the torso and foot. For this purpose, they were integrated with shirt and the shoe insole. The values of acceleration measured by the sensors are sent via Bluetooth to a smartphone. The localization algorithm implemented on the smartphone, presented here, merges data from the shirt and the shoe to track the steps made by the user and filter out the artefacts caused by movements the shirt and torso. The experimental verification of the algorithm is also presented

Readmissions and repeat procedures after catheter ablation for atrial fibrillation

Background: The aim of this study was to assess the frequency of all-cause rehospitalization and due to atrial fibrillation/flutter (AF/AFl), repeat ablation of AF/AFl, mortality within 30 days and 1-year follow-up in patients after AF/AFl ablation procedure. Methods: Using data from the National Health Fund we identified a database comprising 2,022 patients who underwent AF/AFl ablation between January, 2012 and December, 2012 in Poland. The primary endpoint was readmission to hospital with discharge diagnosis AF/AFl. The secondary endpoints included: repeat AF/AFl ablation, cardiovascular hospitalization, all-cause hospitalization, all-cause mortality assessed in 30-day and 1-year time frame. Results: The mean age was 58.6 ± 10.9 years (66.8% male). The mean time of the index ablation hospitalization was 3.8 ± 2.6 days. After discharge, 123 (6.1%) and 540 (26.7%) patients were hospitalized because of AF/AFl within 30 days and 1 year, respectively. During 1-year follow-up, 192 (9.5%) patients underwent subsequent AF/AFl ablations. The patients that underwent the second ablation were younger (56.6 ± 11.0 vs. 59.1 ± 10.8; p = 0.019) and the time of the index hospitalization was shorter (3.75 ± 2.16 vs. 4.45 ± 3.26; p = 0.03). Within 30 days 194 (9.6%) patients were hospitalized and 747 (36.9%) in 1-year follow-up. All-cause mortality was 0.1% and 1.4% in 30-day and 1-year follow-up, respectively. In a 1-year follow-up patients hospitalized from AF/AFl recurrence were more frequently hospital­ized due to cardiovascular diseases other than AF/AFl (9.6% vs. 6.7%; p = 0.026), especially due to hypertension (2.9% vs. 0.7%; p < 0.001). Conclusions: Over 1 out of 4 patients who underwent AF/AFl ablation were hospitalized due to arrhythmia recurrence in 1 year

Sprint Fidelis implantable cardioverter-defibrillators lead patient management and survival: Single center study

Background: Over the last several years significant rises in the use of implanted cardioverter-defibrillators (ICD) have also resulted in a number of associated complications. This number includes lead failure. Sprint Fidelis (SF) ICD lead is regarded as a lead with elevated failure risk. Every center acting in accordance with the guidelines should observe patients more thoroughly especially with recalled leads and run a registry of their follow-up. The aim of this research was to present follow-up of the patients with SF leads (types 6948, 6949) from a single implantation center. Methods: There were 36 SF leads implanted in 36 patients. Mean follow-up period was 76 months (IQR 40.3–86.8). Patients were subjected to regular check-ups in 3 to 6 month intervals. Results: Patients were implanted at a median age of 66.5 years and majority of them had ischemic cardiomyopathy (72%). A majority of the studied population were men (72.2%). Predominantly dual-chamber ICD (ICD-DR) were implanted (50% ICD-DR vs. 47.2% ICD-VR). The guidelines for management of patients implanted with SF were fully implemented. During the follow-up 14 (38.9%) patients died. No deaths were noted that could be attributed to lead failure. In 5 cases lead failure was identified and of these 4 leads were replaced. Median time from implantation to the detection of lead dysfunction was 52 months (IQR 49; 83). The symptoms of failure consisted of: inappropriate shocks, alternating ventricular lead signal, or loss of ventricular stimulation. Conclusions: The follow-up of patients with recalled SF leads in a single center supports that implementation SF management guidelines could be effective in clinical practice

Major gaps in the information provided to patients before implantation of cardioverter defibrillators: a prospective patient European evaluation

AIMS: Information provided to patients prior to implantable cardioverter-defibrillator (ICD) insertion and their participation in the decision-making process are crucial for understanding ICD function and accepting this lifelong therapy. The aim of this study is to evaluate the extent to which different aspects related to ICD and quality of life were transmitted to patients prior to ICD implantation. METHODS AND RESULTS: Prospective, multicenter European study with an online questionnaire initiated by the European Heart Rhythm Association. The questionnaire was filled-in directly and personally by the ICD patients who were invited to participate. A total of 1809 patients (majority in their 40s-70s, with 624 women, 34.5%) from 10 European countries participated in the study. The median time from first ICD implantation was 5 years (interquartile range 2-10). Overall, 1155 patients (71.5%) felt optimally informed at the time of device implantation, however many respondents received no information about ICD-related complications (n = 801, 49.6%), driving restrictions (n = 718, 44.5%), and possibility of end-of-life ICD deactivation (n = 408, 25.4%). Of note, women were less frequently involved in the decision-making process than men (47.3% vs. 55.9%, P = 0.003) and reported to be less often optimally informed before ICD implantation than men (61.2% vs. 76.8%, P < 0.001). More women mentioned the desire to have learned more about ICD therapy and the benefit/risk balance (45.4% vs. 33.7% of men; P < 0.001). CONCLUSIONS: This patient-based evaluation provides alarming findings on the lack of information provided to patients prior ICD implantation, particularly for women

Apple Watch-assisted supraventricular tachycardia detection and qualification for electrophysiological study

Zaburzenia rytmu są częstą przyczyną odczuwanych kołatań serca. Najczęściej objawy występują jedynie okresowo, dlatego też postawienie prawidłowego rozpoznania niejednokrotnie może stanowić wyzwanie. Na rynku dostępnych jest obecnie szereg zakładanych na nadgarstek urządzeń monitorujących czynność rytmu serca. W przedstawionym przypadku, nowoczesna technologia — AppleWatch®, wykryła epizod AVNRT. Przyczyniło się to do szybszej kwalifikacji pacjentki do badania elektrofizjologicznego i wcześniejszego wykonania skutecznej ablacji. Dzięki temu nie dopuszczono do dalszego pogarszania się jakości życia pacjentki oraz rozwoju potencjalnych poważnych powikłań, w tym kardiomioptaii tachyarytmicznej. W przedstawionym przypadku zilustrowano przydatność kliniczną aplikacji mobilnych wykonujących badanie EKG w monitorowaniu rytmu serca pacjentów w codziennej praktyce. Możliwość wykorzystania AppleWatcha® w innych typach zaburzeń rytmu serca wymaga dalszych badań. Poszerzenie obecnych wytycznych, dotyczących wykorzystania nowoczesnych technologii w zaburzeniach rytmu serca, pozostaje tematem dalszych dyskusji.Cardiac arrhythmias are a common cause of heart palpitations. As symptoms usually occur only temporarily, diagnosis is often challenging. The current market offers a variety of wearable heart rhythm monitors. In the presented case, a novel technology, the AppleWatch®, detected an episode of AVNRT. It contributed to faster qualification for electrophysiological study and subsequent successful ablation. As a result, a further decrease in patients’ quality of life was halted. The development of potentially severe complications, including tachycardia-mediated cardiomyopathy, was prevented. This case exemplifies the clinical utility of ECG-based mobile applications in monitoring patients’ heart rhythms in everyday clinical practice. The feasibility of AppleWatch® in other types of arrhythmias remains underinvestigated. Broadening current guidelines for the use of digital health solutions in cardiac rhythm abnormalities should be further discussed

Initial experience with the subcutaneous implantable cardioverter-defibrillator with the real costs of hospitalization analysis in a single Polish center

Background: The recent introduction of an entirely subcutaneous implantable cardioverter-defibril­lator (S-ICD) represents an important progress in the defibrillation technology towards a less invasive approach. This is a single-center observational study of S-ICD implantations in Poland. Methods: The S-ICD was implanted in 11 patients with standard indications for an ICD. Patients in whom the device was implanted were evaluated for adverse events and device function at hospital discharge. All hospitalization costs were calculated and summed up for all patients. Costs were divided into following categories: medical materials, pharmaceuticals, operating theatre staff, cardiology depart­ment staff, laboratory tests, non-laboratory tests and additional non-medical costs. Results: The mean age of patients was 51.6 ± 16.4 years, 9 were men and 2 were women. Four pa­tients had atrial fibrillation as the basal rhythm, 1 patient had atrial flutter and 6 patients had sinus rhythm. All patients had at least one condition that precluded the use of a traditional ICD system or the S-ICD was preferred due to other conditions, i.e. a history complicated transvenous ICD therapy (18%), anticipated higher risk of infection (27%), lack or difficult vascular access (18%), young age and anticipated high cumulated risk of lifetime device therapy (36%). The mean duration of the im­plantation procedure was 2 h. One patient developed a postoperative pocket hematoma. Mean total time of hospitalization was 28 (6–92) days. Average cost of hospitalization per patient was 21,014.29 EUR (minimal = 19,332.71 EUR and maximal = 24,824.14 EUR). Conclusions: S-ICD implantation appears to provide a viable alternative to transvenous ICD, espe­cially for patients without pacing requirements