6 research outputs found
Non-invasive focus localization, right ventricular epicardial potential mapping in patients with an MRI-conditional pacemaker system â a pilot study
Abstract
Background With the advent of magnetic resonance imaging
(MRI) conditional pacemaker systems, the possibility of
performing MRI in pacemaker patients has been introduced.
Besides for the detailed evaluation of atrial and ventricular
volumes and function, MRI can be used in combination with
body surface potential mapping (BSPM) in a non-invasive
inverse potential mapping (IPM) strategy. In non-invasive
IPM, epicardial potentials are reconstructed from recorded
body surface potentials (BSP). In order to investigate whether
an IPM method with a limited number of electrodes could be
used for the purpose of non-invasive focus localization, it was
applied in patients with implanted pacing devices. Ventricular
paced beats were used to simulate ventricular ectopic foci.
Methods Ten patients with an MRI-conditional pacemaker
system and a structurally normal heart were studied. Patientspecific
3D thorax volume models were reconstructed from
the MRI images. BSP were recorded during ventricular pacing.
Epicardial potentials were inversely calculated from the
BSP. The site of epicardial breakthrough was compared to the
position of the ventricular lead tip on MRI and the distance
between these points was determined.
Results For all patients, the site of earliest epicardial depolarization
could be identified. When the tip of the pacing lead
was implanted in vicinity to the epicardium, i.e. right ventricular
(RV) apex or RV outflow tract, the distance between lead
tip position and epicardial breakthrough was 6.0±1.9 mm.
Conclusions In conclusion, the combined MRI and IPM
method is clinically applicable and can identify sites of earliest
depolarization with a clinically useful accuracy
[Diagnostic image (175). A man with fast and irregular palpitations. Atrial fibrillation and Wolff-Parkinson-White syndrome]
A 51-year-old man with palpitations had fast, broad and irregular QRS complexes on his ECG, due to atrial fibrillation and Wolff-Parkinson-White syndrome
Alterations in the peripheral circulation in patients with mild heart failure.
OBJECTIVE: In patients with severe heart failure, compensatory mechanisms fail to provide adequate blood supply to the peripheral circulation, especially when the metabolic need is increased. The aim of this study was to assess alterations in the peripheral circulation in patients with mild heart failure using ultrasound Doppler. METHODS: In 19 controls and in 11 patients with mild heart failure, Doppler spectra were recorded from the carotid, the brachial and the femoral artery at rest and, from the latter two arteries, during post-occlusive reactive hyperemia. Parameters derived from these Doppler spectra were used to make comparisons between both groups. RESULTS: At rest, the duration of the acceleration of blood was shorter in controls, the acceleration was steeper in controls and the deceleration duration was longer in controls as compared to the patients. Differences in the response to reactive hyperemia were only observed in the common femoral artery. CONCLUSIONS: In patients with mild heart failure, significant alterations in the peripheral circulation were observed especially for the femoral artery. These changes are caused by the impairment of the left ventricular function and by adjustments in the compensatory mechanism of the peripheral circulation
Catheter ablation of tachyarrhythmia substrates in children
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Persistent phrenic nerve palsy after atrial fibrillation ablation: Follow-up data from The Netherlands Heart Registration
Background Persistent phrenic nerve palsy (PNP) is an established complication of atrial fibrillation (AF) ablation, especially during cryoballoon and thoracoscopic ablation. Data on persistent PNP reversibility is limited because most patients recover <24 h. This study aims to investigate persistent PNP recovery, freedom of PNP-related symptoms after AF ablation and identify baseline variables associated with the occurrence and early PNP recovery in a large nationwide registry study. Methods In this study, we used data from the Netherlands Heart Registration, comprising data from 9549 catheter and thoracoscopic AF ablations performed in 2016 and 2017. PNP data was available of 7433 procedures, and additional follow-up data were collected for patients who developed persistent PNP. Results Overall, the mean age was 62 +/- 10 years, and 67.7% were male. Fifty-four (0.7%) patients developed persistent PNP and follow-up was available in 44 (81.5%) patients. PNP incidence was 0.07%, 0.29%, 1.41%, and 1.25%, respectively for patients treated with conventional-RF, phased-RF, cryoballoon, and thoracoscopic ablation respectively. Seventy-one percent of the patients fully recovered, and 86% were free of PNP-related symptoms after a median follow-up of 203 (113-351) and 184 (82-359) days, respectively. Female sex, cryoballoon, and thoracoscopic ablation were associated with a higher risk to develop PNP. Patients with PNP recovering <= 180 days had a larger left atrium volume index than those with late or no recovery. Conclusion After AF ablation, persistent PNP recovers in the majority of patients, and most are free of symptoms. Female patients and patients treated with cryoballoon or thoracoscopic ablation are more prone to develop PNP