Evidence map›Paper›PMID 26404298›Full record

Trial reportSensors (Basel, Switzerland)2015

Towards Low Energy Atrial Defibrillation.

Philip Walsh, Vivek Kodoth, David McEneaney, Paola Rodrigues, Jose Velasquez, Niall Waterman, Omar Escalona

Open access · goldAbstract readRandomized Controlled Trial
In one paragraph

Trial report in Sensors (Basel, Switzerland), 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
0.6field-weighted citation impact, top 27% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed, 5 citations in OpenAlex.

  1. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

7 authors at 3 institutions in 1 country.

Philip WalshCentre for Advanced Cardiovascular Research, Ulster University, BT37 0QB, UK. Walsh-P3@email.ulster.ac.uk.
Vivek KodothThe Heart Centre, Royal Victoria Hospital, Belfast, BT12 6BA, UK. Vivek.kodoth@rbch.nhs.uk.
David McEneaneyCraigavon Area Hospital, Craigavon, BT63 5QQ, UK. David.McEneaney@southerntrust.hscni.net.
Paola RodriguesCentre for Advanced Cardiovascular Research, Ulster University, BT37 0QB, UK. Rodrigues-P@email.ulster.ac.uk.
Jose VelasquezCentre for Advanced Cardiovascular Research, Ulster University, BT37 0QB, UK. Velasquez-J@email.ulster.ac.uk.
Niall WatermanCentre for Advanced Cardiovascular Research, Ulster University, BT37 0QB, UK. n.waterman@ulster.ac.uk.
Omar EscalonaCentre for Advanced Cardiovascular Research, Ulster University, BT37 0QB, UK. oj.escalona@ulster.ac.uk.
University of Ulster · GBCraigavon Area Hospital · GBRoyal Victoria Hospital · GB

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

A wireless powered implantable atrial defibrillator consisting of a battery driven hand-held radio frequency (RF) power transmitter (ex vivo) and a passive (battery free) implantable power receiver (in vivo) that enables measurement of the intracardiac impedance (ICI) during internal atrial defibrillation is reported. The architecture is designed to operate in two modes: Cardiac sense mode (power-up, measure the impedance of the cardiac substrate and communicate data to the ex vivo power transmitter) and cardiac shock mode (delivery of a synchronised very low tilt rectilinear electrical shock waveform). An initial prototype was implemented and tested. In low-power (sense) mode, >5 W was delivered across a 2.5 cm air-skin gap to facilitate measurement of the impedance of the cardiac substrate. In high-power (shock) mode, >180 W (delivered as a 12 ms monophasic very-low-tilt-rectilinear (M-VLTR) or as a 12 ms biphasic very-low-tilt-rectilinear (B-VLTR) chronosymmetric (6ms/6ms) amplitude asymmetric (negative phase at 50% magnitude) shock was reliably and repeatedly delivered across the same interface; with >47% DC-to-DC (direct current to direct current) power transfer efficiency at a switching frequency of 185 kHz achieved. In an initial trial of the RF architecture developed, 30 patients with AF were randomised to therapy with an RF generated M-VLTR or B-VLTR shock using a step-up voltage protocol (50-300 V). Mean energy for successful cardioversion was 8.51 J ± 3.16 J. Subsequent analysis revealed that all patients who cardioverted exhibited a significant decrease in ICI between the first and third shocks (5.00 Ω (SD(σ) = 1.62 Ω), p < 0.01) while spectral analysis across frequency also revealed a significant variation in the impedance-amplitude-spectrum-area (IAMSA) within the same patient group (|∆(IAMSAS1-IAMSAS3)[1 Hz - 20 kHz] = 20.82 Ω-Hz (SD(σ) = 10.77 Ω-Hz), p < 0.01); both trends being absent in all patients that failed to cardiovert. Efficient transcutaneous power transfer and sensing of ICI during cardioversion are evidenced as key to the advancement of low-energy atrial defibrillation.

Indexed as

Defibrillators, ImplantableElectric Power SuppliesComputer SimulationCoronary SinusFourier AnalysisHeart AtriaHumansRadio WavesTime FactorsWavelet Analysisbattery-freedefibrillatorimpedanceimplantableRFwireless

Identifiers

PMID26404298
PMCPMC4610542
OpenAlexW2170095098

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.