Background: Chronological changes in ablation lesions after cryoballoon ablation (CBA) and hot balloon ablation (HBA) of atrial fibrillation (AF) remain unclear. Methods: Of 90 patients who underwent ...initial balloon-based catheter ablation of AF and cardiac magnetic resonance imaging (cMRI) 3 months after ablation, data from 48 propensity score-matched patients (24 per group; 34 males; age 62±10 years) were analyzed. High-density pulmonary vein-left antrum (PV-LA) voltage mapping was performed after PV isolation, and low voltage areas around the PV ostia were defined as the total acute ablation lesion area (cm2). cMRI-derived dense fibrotic tissue localized around PVs was defined as the total chronic ablation lesion area (cm2). The percentage of total ablation lesion areas to total PV-LA surface area (%ablation lesion) was calculated during each phase, and %acute ablation lesion and %chronic ablation lesion areas were compared in patients who had undergone CBA and HBA. Results: The %acute ablation lesion area was larger for the CBA group than for the HBA group (30.8±5.8% vs. 23.0±5.5%, p < 0.001). There was no difference in %chronic cMRI-derived ablation lesion area (24.8±10.8% vs. 21.1±11.6%, p = 0.26) between groups. The rates of chronic AF recurrence were 12.5% and 8.3%, respectively (p = 0.45; log-rank test). LA volume and LA surface area were strongly associated with AF recurrence, but %chronic ablation lesion area was not (27±8% vs. 23±12%, p = 0.39). Conclusion: Large acute ablation lesions after CBA were smaller during the chronic phase. The size of chronic ablation lesions and the rate of AF recurrence were both similar for CBA and HBA.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Abstract
Atrial fibrillation (AF) is a progressive disease that starts with structural or functional changes in the left atrium and left ventricle, and evolves from paroxysmal toward sustained forms. ...Early detection of structural or functional changes in the left atrium and left ventricle in the paroxysmal stage could be useful for identifying a higher risk of progression to persistent AF and future cardio-cerebrovascular events. The aim of this study was to test the hypothesis that the feature tracking (FT) left atrial (LA) strain and left ventricular (LV) extracellular volume fraction (ECV) derived from cardiovascular magnetic resonance (CMR) could detect early changes in remodeling of the left atrium and ventricle in the paroxysmal AF (PAF) stage. The participants were comprised of 106 PAF patients (age, 66.1 ± 10.7 years; 66% male) who underwent clinical CMR before pulmonary vein isolation and 20 control subjects (age, 68.3 ± 8.6 years; 55% male). The CMR-FT LA strain/phasic function and LV-ECV were compared between the PAF and control groups. The total and passive LA empty fraction (LAEF) and LA strain (corresponding to LA reservoir and conduit function) were decreased in the PAF group as compared to the control group. However, active LAEF (corresponding to the LA booster pump function) did not differ significantly between the PAF group (33.9 ± 10.9%) and control group (37.9 ± 13.3%, p = 0.15), while the active LA strain (corresponding to the LA booster pump function) was significantly decreased in the PAF group (11.4 ± 4.3 vs. 15.2 ± 5.6%, p = 0.002). The LV-ECV was significantly greater in the PAF group (28.7 ± 2.8%) than control group (26.6 ± 2.0%, p = 0.002). In the PAF group, the LV-ECV correlated significantly with the E/e′ and LA volume index. Regarding the LA strain, correlations were seen between the LV-ECV and both the reservoir function and conduit function. CMR-FT LA strain in combination with the LV-ECV in a single clinical study offers a potential imaging marker that identifies LA/LV remodeling including subtle LA booster pump dysfunction undetectable by the conventional booster pump LAEF in the PAF stage.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Abstract
Low-temperature growth, as well as the transfer free growth on substrates, is the major concern of graphene research for its practical applications. Here we propose a simple method to ...achieve the transfer free graphene growth on SiO
2
covered Si (SiO
2
/Si) substrate at 250 °C based on a solid-liquid-solid reaction. The key to this approach is the catalyst metal, which is not popular for graphene growth by chemical vapor deposition. A catalyst metal film of 500 nm thick was deposited onto an amorphous C (50 nm thick) coated SiO
2
/Si substrate. The sample was then annealed at 250 °C under vacuum condition. Raman spectra measured after the removal of the catalyst by chemical etching showed intense G and 2D peaks together with a small D and intense SiO
2
related peaks, confirming the transfer free growth of multilayer graphene on SiO
2
/Si. The domain size of the graphene confirmed by optical microscope and atomic force microscope was about 5 μm in an average. Thus, this approach will open up a new route for transfer free graphene growth at low temperatures.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Despite emerging recognition of interactions between heart failure (HF) and liver dysfunction, the impact of cardiac hepatopathy on patients with HF undergoing cardiac resynchronization therapy (CRT) ...has not been fully elucidated. Albumin–bilirubin (ALBI) score is a new assessment of liver function. The relationship between liver dysfunction severity based on ALBI score and clinical outcomes of patients with HF receiving CRT is unclear. Clinical records of 274 patients who underwent CRT device implantation between March 2003 and October 2020 were retrospectively investigated. ALBI score was calculated based on serum albumin and total bilirubin levels obtained before CRT device implantation. Patients were divided into three groups based on ALBI score: first tertile (ALBI ≤ − 2.62,
n
= 91)), second tertile (− 2.62 < ALBI < − 2.13,
n
= 92), and third tertile (ALBI ≥ − 2.13,
n
= 91). The study endpoint was all-cause mortality. The third tertile group had more advanced NYHA functional class, lower hemoglobin levels, and higher total bilirubin, aspartate aminotransferase, γ-glutamyl transferase, and N-terminal Pro-B-type natriuretic peptide levels (all
p
< 0.05). The third tertile group also had a higher prevalence of moderate or severe tricuspid regurgitation and higher tricuspid regurgitation pressure gradient (all
p
< 0.05). CRT response rates were significantly lower in the third tertile group. During a median (interquartile range) follow-up of 30 (9–60) months, 104 (37.9%) patients died. The third tertile group had significantly higher rates of all-cause mortality (log-rank
p
< 0.001). Higher ALBI score was significantly associated with all-cause mortality, even after adjusting for clinically relevant factors, a conventional validated risk score, and echocardiographic parameters related to right HF (all
p
< 0.01). Higher ALBI score before CRT device implantation is associated with HF severity, hepatic congestion and impairment due to right HF, lower CRT response, and higher all-cause mortality in CRT recipients.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The intracardiac electrograms are shown during scanned single premature ventricular extrastimuli with a decreasing coupling interval in a very short RP tachycardia. What is the diagnosis and is the ...fast pathway essential for sustaining the tachycardia?
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK, VSZLJ
The fractionated potential area with a fractionation threshold of ≥8, highlighted in white, was seen in the mid-septal region (Figure 2), and cryomapping at −30°C with a 6 mm tip cryoablation ...catheter (Freezor Xtra, Medtronic) successfully terminated the tachycardia within 14 s in that area (Figure 3). ...we delivered two cryothermal applications at −70°C for 240 s twice at that site, which successfully rendered the AVNRT noninducible. In this case, the Advisor™ HD Grid catheter and fractionation map in the EnSite™ X EP system with relatively high-sensitive settings of the width (5 ms), refractory time (6 ms), and roving sensitivity (0.01 mV) were also useful for detecting the target SP area. 3 The EnSite™ X EP system has improved the suppression of the noise level and acquired 18 532 points during this procedure, which allowed the creation of a reliable fractionation map. A fractionation Map during sinus rhythm was also created, but the successful ablation site did not correspond to the fractionated area (Figure 4). ...it appeared that the fractionated potentials were exclusively acquired during the tachycardia.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK, VSZLJ
Introduction
A new hot balloon system that registers balloon surface temperature (BST) during energy delivery is now available for clinical use in Japan. This study sought to investigate the utility ...of BST measurement for achievement of pulmonary vein isolation (PVI) by a single‐shot energy delivery strategy during hot balloon ablation (HBA).
Methods
We applied and tested the system in 30 consecutive patients undergoing HBA for paroxysmal or early‐persistent atrial fibrillation (AF). We also performed real‐time PV potential monitoring using a circular catheter.
Results
Acute PVI was achieved with single hot balloon shots in 88% (106/120) of the PVs. Real‐time BSTs and PV potentials were recorded in all cases. Mean BST at documentation of PVI was 49.4°C, and acute reconnections were observed in most cases (86%, 12/14) in which the single‐shot technique was ineffective. Time‐to‐isolation (TTI) (23.1 ± 8.7 s vs. 36.3 ± 9.3 s, p < .01) and median BST (59.9 ± 2.6°C vs. 55.7 ± 1.9°C, p < .01) differed significantly between cases in which PVI was achieved (vs. those in which PVI was not achieved). Multivariable analysis revealed strong association between both TTI and median BST and acute PVI. The best median BST cutoff value for achieving PVI with a single shot was >58.7°C (sensitivity 67.0%, specificity 100%).
Conclusion
Our data suggest that real‐time BST monitoring during energy applications is useful for predicting achievement of acute PVI by a single shot during HBA.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK, VSZLJ
Background
Although pulmonary vein isolation (PVI) for atrial fibrillation (AF) utilizing radiofrequency (RF) applications with a very high‐power and short‐duration (vHPSD) has shortened the ...procedure time, the determinants of pulmonary vein (PV) gaps in the first‐pass PVI and acute PV reconnections are unclear.
Methods
An extensive encircling PVI was performed with the QDOT MICRO catheter with a vHPSD (90 W–4 s) in 30 patients with AF (19 men, 64 ± 10 years). The association of the PV gap sites (first‐pass PVI failure, acute PV reconnections spontaneous reconnections or dormant conduction provoked by adenosine triphosphate or both) with the left atrial (LA) wall thickness and LA bipolar voltage on the PVI line and ablation‐related parameters were assessed.
Results
PV gaps were observed in 29 (6%) of 480 segments (16 segments per patient) in 17 patients (56%). The PV gaps were associated with the LA wall thickness, bipolar voltage, and the number of RF points (LA wall thickness, 2.5 ± 0.5 vs. 1.9 ± 0.4 mm, p < .001; bipolar voltage, 2.59 ± 1.62 vs. 1.34 ± 1.14 mV, p < .001; RF points, 6 ± 2 vs. 4 ± 2, p = .008) but were not with the other ablation‐related parameters. Receiver operating characteristic curves yielded that an LA wall thickness ≥2.3 mm and bipolar voltage ≥2.40 mV were determinants of PV gaps with an area under the curve of 0.82 and 0.73, respectively.
Conclusions
The LA voltage and wall thickness on the PV‐encircling ablation line were highly associated with PV gaps using the 90 W/4 s‐vHPSD ablation.
The left atrial (LA) voltage and wall thickness on the pulmonary vein (PV)‐encircling ablation line were highly associated with PV gaps when using the 90 W/4 s‐vHPSD ablation. The determined cut‐off values for predicting PV gaps were 2.40 mV for LA voltage and 2.3 mm for wall thickness, respectively. These findings provide valuable clinical insights into enhancing first‐pass PV isolation with the 90 W/4 s‐vHPSD ablation technique.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK, VSZLJ