Using computed tomogram atrial myocardial thickness maps in high-power short-duration radiofrequency pulmonary vein isolation: UTMOST AF.

Background: High-power short-duration (HPSD) ablation creates wide, shallow lesions using radiofrequency (RF) heating. It is uncertain if adjusting RF energy based on atrial wall thickness provides extra benefits. We studied the safety and effectiveness of tailored HPSD energy based on left atrial (LA) wall thickness (LAWT) for circumferential pulmonary vein isolation (CPVI) in patients with paroxysmal atrial fibrillation (PAF). Methods: We enrolled 212 patients (68.4% male, mean age: 59.5 ± 11.0 years) and randomly assigned them to two groups: LAWT-guided CPVI (WT, n = 108) and conventional CPVI (control, n = 104). Both groups used an open irrigated-tip deflectable catheter to apply 50 W for 10 s to the posterior LA, while controls used 60 W for 15 s on other LA regions. RF delivery time in WT was titrated (15 s at LAWT > 2.1 mm, 13 s at 1.4-2.1 mm, and 11 s at <1.4 mm) according to the computed tomogram-myocardial thickness color map. Results: After a mean follow-up of 13.4 ± 7.0 months, the WT and control groups showed no significant difference regarding clinical recurrence rate (13.9% vs. 5.8%, respectively; p = .061) and major complication rate (4.6% vs. 3.8%, respectively; p > .999). The total procedure time, cardioversion rate, and post-procedural AAD prescription rates did not significantly differ between the groups. Conclusions: The LAWT-guided energy titration strategy did not result in improved procedural safety and efficacy compared to the conventional 50-60 W-HPSD CPVI in patients with PAF.

Association of extra-pulmonary vein triggers with low-voltage area and clinical recurrence in patients with atrial fibrillation undergoing catheter ablation.

Background and Objectives: Although extra-pulmonary vein (PV) triggers (ExPVTs) play a role in atrial fibrillation (AF) recurrence after catheter ablation (AFCA), the mechanism is unknown. We explored whether the locations of ExPVTs were associated with low-voltage scar areas (LVAs). Methods: Among 2255 consecutive patients who underwent a de novo AFCA, 1696 (male 72.1%, median 60 years old, paroxysmal 64.7%) were included who underwent isoproterenol provocation and voltage mapping of the left atrium (LA) during their procedures. We investigated the associations between ExPVTs and their mean LA voltage and colocalization of ExPVTs within LVAs (<0.2 mV). Results: We observed ExPVTs in 181 (10.7%) patients (60 in the LA, 99 in the right atrium [RA], 16 biatrial, and 6 unmappable). A lower mean LA voltage was independently associated with the existence of ExPVTs (OR 0.77 per 1 SD mV increase, 95% CI 0.60-0.99, p = .039). Among 76 patients who had ExPVTs[LA], 43 (56.6%) had ExPVTs within LVAs. During a median of a 42-month follow-up, patients with ExPVTs had a higher AF recurrence than those without (HR 1.87, 95% CI 1.48-2.37, Log-rank p < .001), but colocalization of ExPVTs and LVAs (Log-rank p = .544) and the anatomical location of ExPVTs (Log-rank p = .084) did not affect the rhythm outcome. Conclusions: The presence of ExPVTs was associated with low LA voltage and poor rhythm outcome post-AFCA, but the colocalization of ExPVTs and LVA in LA did not affect rhythm outcome.

Clinical Characteristics and Rhythm Outcomes in Patients With Atrial Myopathy After Successful Catheter Ablation of Atrial Fibrillation.

BACKGROUND: Although successful atrial fibrillation (AF) ablation can maintain sinus rhythm and reduce the left atrial (LA) dimension, blunted LA reverse remodeling can be observed in patients with atrial myopathy. We explored the potential mechanisms and long-term outcomes in patients with blunted LA reverse remodeling after successful AF catheter ablation. METHODS AND RESULTS: We included 1685 patients who underwent baseline and 1-year follow-up echocardiograms, had a baseline LA dimension ≥40 mm, and did not have a recurrence of AF within a year. The patients were divided into tertile groups according to the delta value of the change in LA dimension on the preprocedure and 1-year postprocedure echocardiography. After propensity score matching for age, sex, AF type, and LA dimension, 1272 patients were finally included in the analyses (424 in each group; the least/blunted, moderate, and the most reverse remodeling group). The patients in the T1 group (blunted LA reverse remodeling) were independently associated with higher left ventricular mass index (odds ratio [OR], 1.014 [95% CI, 1.005-1.022], P=0.001), change in ΔH2FPEF score (heavy, hypertensive, atrial fibrillation, pulmonary hypertension, elder, filling pressure) score (OR, 1.445 [95% CI, 1.121-1.861], P=0.004), ventricular epicardial adipose tissue volume (OR, 1.010 [95% CI, 1.003-1.017], P=0.003), thinner LA wall thickness (OR, 0.461 [95% CI, 0.271-0.785], P=0.004), lower LA voltage (OR, 0.670 [95% CI, 0.499-0.899], P=0.008), and showed higher long-term AF recurrence (log-rank P<0.001) than other groups. CONCLUSIONS: Blunted LA reverse remodeling after AF catheter ablation, which is suggestive of atrial myopathy, was independently associated with a larger ventricular epicardial adipose tissue volume and worsening of H2FPEF score. Blunted LA reverse remodeling after AF catheter ablation was also an independent predictor for higher recurrences of AF post-1-year AF catheter ablation.

Comparison of pulmonary vein isolation using cryoballoon, high-power short-duration, and conventional radiofrequency ablation for atrial fibrillation: a propensity score-weighted study.

Background: The comparative efficacy, saftey, and heart rate variability (HRV) parameters after pulmonary vein isolation using cryoballoon (Cryo-PVI), high-power short-duration (HPSD-PVI), and conventional radiofrequency ablation (conventional-PVI) for atrial fibrillation (AF) is unclear. Materials and methods: In this propensity score-weighted, retrospective analysis of a single-center cohort, we analyzed 3,395 patients (26.2% female, 74.5% paroxysmal AF) who underwent AF catheter ablation without an empirical left atrial ablation. Procedural factors, recurrence rates, complication rates, and the post-procedural HRV parameters were compared across the Cryo-PVI (n = 625), HPSD-PVI (n = 748), and conventional-PVI (n = 2,022) groups. Results: Despite the shortest procedural time in the Cryo-PVI group (74 min for Cryo-PVI vs. 104 min for HPSD-PVI vs. 153 min for conventional-PVI, p < 0.001), the major complication (p = 0.906) and clinical recurrence rates were similar across the three ablation groups (weighted log-rank, p = 0.824). However, the Cryo-PVI group was associated with a significantly lower risk of recurrent AF in patients with paroxysmal AF [weighted hazard ratio (WHR) 0.57, 95% confidence interval (CI) 0.37-0.86], whereas it was associated with a higher risk of recurrent AF in patients with persistent AF (WHR 1.41, 95% CI 1.06-1.89, p for interaction of <0.001) compared with the conventional-PVI group. In the subgroup analysis for the HRV, the Cryo-PVI group had the highest low-frequency-to-high-frequency ratio at 1-year post-procedure, whereas the HPSD-PVI group had the lowest low-frequency-to-high-frequency ratio at 1-year post-procedure (p < 0.001). Conclusions: The Cryo-PVI group had better rhythm outcomes in patients with paroxysmal AF but worse rhythm outcomes in patients with persistent AF and a higher long-term post-procedural sympathetic nervous activity and sympatho-vagal balance compared with the conventional-PVI group.

Late recurrence of atrial fibrillation 5 years after catheter ablation: predictors and outcome.

AIMS: Atrial fibrillation (AF) is a chronic progressive disease that continuously recurs even after successful AF catheter ablation (AFCA). We explored the mechanism of long-term recurrence by comparing patient characteristics and redo-ablation findings. METHODS AND RESULTS: Among the 4248 patients who underwent a de novo AFCA and protocol-based rhythm follow-up at a single centre, we enrolled 1417 patients [71.7% male, aged 60.0 (52.0-67.0) years, 57.9% paroxysmal AF] who experienced clinical recurrences (CRs), and divided them according to the period of recurrence: within one year (n = 645), 1-2 years (n = 339), 2-5 years (n = 308), and after 5 years (CR>5 yr, n = 125). We also compared the redo-mapping and ablation outcomes of 198 patients. In patients with CR>5 yr, the proportion of paroxysmal AF was higher (P = 0.031); however, the left atrial (LA) volume (quantified by computed tomography, P = 0.003), LA voltage (P = 0.003), frequency of early recurrence (P < 0.001), and use of post-procedure anti-arrhythmic drugs (P < 0.001) were lower. A CR>5 yr was independently associated with a low LA volume [odds ratio (OR) 0.99 (0.98-1.00), P = 0.035], low LA voltage [OR 0.61 (0.38-0.94), P = 0.032], and lower early recurrence [OR 0.40 (0.23-0.67), P < 0.001]. Extra-pulmonary vein triggers during repeat procedures were significantly greater in patients with a CR>5 yr, despite no difference in the de novo protocol (P for trend 0.003). The rhythm outcomes of repeat ablation procedures did not differ according to the timing of the CR (log-rank P = 0.330). CONCLUSIONS: Patients with a later CR exhibited a smaller LA volume, lower LA voltage, and higher extra-pulmonary vein triggers during the repeat procedure, suggesting AF progression.

The Value of Programmed Ventricular Extrastimuli From the Right Ventricular Basal Septum During Supraventricular Tachycardia.

BACKGROUND: The difference between the right ventricular (RV) apical stimulus-atrial electrogram (SA) interval during resetting of supraventricular tachycardia (SVT) versus the ventriculoatrial (VA) interval during SVT (ΔSA-VAapex) is an established technique for discerning SVT mechanisms but is limited by a significant diagnostic overlap. OBJECTIVES: This study hypothesized that the difference between the RV SA interval during resetting of SVTs versus the VA interval during SVTs (ΔSA-VA) would yield a more robust differentiation of atrioventricular nodal re-entrant tachycardia (AVNRT) from atrioventricular reciprocating tachycardia (AVRT) when using the RV basal septal stimulation (ΔSA-VAbase) as compared to the RV apical stimulation (ΔSA-VAapex). Moreover, it was predicted that the ΔSA-VAbase might distinguish septal from free wall accessory pathways (APs) effectively. METHODS: In this prospective study, 105 patients with AVNRTs (age 48 ± 20 years, 44% male) and 130 with AVRTs (age 26 ± 18 years, 54% male) underwent programmed ventricular extrastimuli delivered from both the RV basal septum and RV apex. The ΔSA-VA values were compared between the 2 sites. RESULTS: The ΔSA-VAbase was shorter than the ΔSA-VAapex during AVRT (44 ± 30 ms vs 58 ± 29 ms; P < 0.001), and the opposite occurred during AVNRT (133 ± 31 ms vs 125 ± 25 ms; P = 0.03). A ΔSA-VAbase of ≧85 milliseconds had a sensitivity of 97% and specificity of 96% for identifying AVNRT. Furthermore, a ΔSA-VAbase of 45-85 milliseconds identified AVRT with left free wall APs (sensitivity 86%, specificity 95%), 20-45 milliseconds for posterior septal APs (sensitivity 72%, specificity 96%), and <20 milliseconds for right free wall or anterior/mid septal APs (sensitivity 86%, specificity 98%). CONCLUSIONS: The ΔSA-VAbase during programmed ventricular extrastimuli produced a robust differentiation between AVNRT and AVRT regardless of the AP location with ≧85 milliseconds as an excellent cutoff point. This straightforward technique further allowed localizing 4 general AP sites.

Machine learning for emerging infectious disease field responses.

Emerging infectious diseases (EIDs), including the latest COVID-19 pandemic, have emerged and raised global public health crises in recent decades. Without existing protective immunity, an EID may spread rapidly and cause mass casualties in a very short time. Therefore, it is imperative to identify cases with risk of disease progression for the optimized allocation of medical resources in case medical facilities are overwhelmed with a flood of patients. This study has aimed to cope with this challenge from the aspect of preventive medicine by exploiting machine learning technologies. The study has been based on 83,227 hospital admissions with influenza-like illness and we analysed the risk effects of 19 comorbidities along with age and gender for severe illness or mortality risk. The experimental results revealed that the decision rules derived from the machine learning based prediction models can provide valuable guidelines for the healthcare policy makers to develop an effective vaccination strategy. Furthermore, in case the healthcare facilities are overwhelmed by patients with EID, which frequently occurred in the recent COVID-19 pandemic, the frontline physicians can incorporate the proposed prediction models to triage patients suffering minor symptoms without laboratory tests, which may become scarce during an EID disaster. In conclusion, our study has demonstrated an effective approach to exploit machine learning technologies to cope with the challenges faced during the outbreak of an EID.

High density mapping guided partial antral ablation for a pulmonary vein isolation.

The muscular discontinuities at the pulmonary vein (PV)-left atrial (LA) junction are known. The high-density mapping may help to find the muscular discontinuity. This study evaluated the efficacy of a partial antral ablation for a pulmonary vein (PV) isolation using high density (HD) mapping. A total of 60 drug-refractory atrial fibrillation (AF) patients undergoing catheter ablation were enrolled. The detailed activation mapping of each PV and LA junction was performed using an HD mapping system, and each PV segment's activation pattern was classified into a "directly-activated from the LA" or "passively-activated from an adjacent PV segment" pattern. The antral ablations were performed at the directly-activated PV segments only when the PV had "passively-activated segments". If the PV did not contain passively-activated segments, a circumferential antral ablation was performed on those PVs. A "successful partial antral ablation" was designated if the electrical isolation of targeted PV was achieved by ablation at the directly-activated segments only. If the isolation was not achieved even though all directly-activated segments were ablated, a "failed partial antral ablation" was designated, and then a circumferential ablation was performed. Among 240 PVs, passively-activated segments were observed in 140 (58.3%) PVs. Both inferior PVs had more passively-activated segments than superior PVs, and the posteroinferior segments had the highest proportion of passive activation. The overall rate of successful partial antral ablation was 85%. The atrial tachyarrhythmia recurrence was observed in 10 patients (16.7%) at 1-year. HD mapping allowed the evaluation of the detailed activation patterns of the PVs, and passively-activated segments may represent muscular discontinuity. Partial antral ablation of directly-activated antral segments only was feasible and effective for a PVI.

Combinatorial discovery of thermoresponsive cycloammonium ionic liquids.

This work demonstrated, for the first time, the combinatorial discovery and rational identification of small-molecule cycloammonium-based thermoresponsive ionic liquids that exhibit LCST phase transition and carry attractive Tc values in water.

Long-Term Outcome of Additional Superior Vena Cava to Septal Linear Ablation in Catheter Ablation of Atrial Fibrillation.

Background We previously reported the benefit of linear ablation from the superior vena cava to the right atrial septum (SVC-L) within a year after circumferential pulmonary vein isolation (CPVI) in patients with paroxysmal atrial fibrillation (AF). We explored the long-term effects of SVC-L and its potential related mechanisms. Methods and Results Among 2140 consecutive patients with AF ablation, we included 614 patients (73.3% male, aged 57.8±10.7 years, 13.7% with persistent AF) who did not undergo an extra-pulmonary vein left atrial ablation after propensity score matching; of those, 307 had additional SVC-L and 307 had CPVI alone. We evaluated the heart rate variability and computational modeling study to explore mechanisms. Although the procedure time was longer in the SVC-L group than the CPVI group (P<0.001), the complication rates did not differ (P=0.560). During 40.5±24.4 months of follow-up, the rhythm outcome was significantly better in the SVC-L group than the CPVI group (log rank, P<0.001). At 2-year follow-up of heart rate variability, a significantly higher mean heart rate (P=0.018) and a lower ratio of low/high-frequency components (P=0.011) were found with SVC-L than CPVI alone. In realistic in silico biatrial modeling, which reflected the electroanatomies of 10 patients, SVC-L significantly reduced biatrial dominant frequency compared with CPVI alone (P<0.001) and increased AF termination and defragmentation rates (P=0.033). Conclusions SVC-L ablation in addition to CPVI significantly improved the long-term rhythm outcome over 2 years after AF catheter ablation by mechanisms involving autonomic modulation and AF organization.

Impact of persistent left superior vena cava on radiofrequency catheter ablation in patients with atrial fibrillation.

AIMS: The impact of persistent left superior vena cava (PLSVC) in atrial fibrillation (AF) patients undergoing radiofrequency catheter ablation (RFCA) is not well known. We performed this analysis to evaluate the electrophysiological characteristics of PLSVC and its role in triggering and maintaining AF. METHODS AND RESULTS: Patients with AF referred to two tertiary hospitals were screened and patients with PLSVC in pre-RFCA imaging studies were enrolled. Among 3967 patients, PLSVC was present in 36 patients (0.9%). There were four morphological types of PLSVC: type 1, atresia of the right superior vena cava (SVC) (n = 2); type 2A, dual SVCs with an anastomosis between right and left SVCs (n = 15); type 2B, dual SVCs without an anastomosis (n = 16); type 3, PLSVC draining into the left atrium (LA; n = 2); and unclassified in one patient. Thirty-two patients underwent RFCA and electrophysiology study focusing on PLSVC: PLSVC was the trigger of AF in 48.4% of patients and the driver of AF in 46.9% of patients. Cumulatively, PLSVC was a trigger or driver of AF in 22 patients (68.8%). Whether to ablate PLSVC was determined by the results of electrophysiology study, and no significant difference in the late recurrence rate was observed between patients who did and did not have either trigger or driver from PLSVC. CONCLUSION: Pre-RFCA cardiac imaging revealed PLSVC in 0.9% of AF patients. This study demonstrated that PLSVC has an important role in initiating and maintaining AF in substantial proportion of patients. Electrophysiology study focusing on PLSVC can help to decide whether to ablate PLSVC.

Radiofrequency catheter ablation of accessory pathways at the site of prior valve surgery.

BACKGROUND: Radiofrequency catheter ablation (RFCA) for accessory pathways (APs) at the site of prior valve surgery (VS) remains challenging. We aimed to clarify the factors associated with successful RFCA for such APs. METHODS: Upon reviewing a RFCA registry and previous case reports, we included nine patients who underwent RFCA of APs at the site of prior VS (total-VS group; age, 34.0 [24.5-45.0] years; men, 4/9) and 196 patients who underwent RFCA of APs with no history of VS (no-VS group; age, 40.5 [23.0-54.0] years; men, 114/196). Electrophysiological features, procedural details, and outcomes were examined. RESULTS: Accessory pathway exhibited decremental conduction in four of nine patients in the total-VS group. The number of RFCA attempts was significantly higher in the total-VS group than in the no-VS group (10.0 [4.5-14.5] vs 2.0 [1.0-3.0]; P < 0.001). In four patients who underwent mitral VS, successful RFCA was achieved using the transaortic approach, coronary sinus (CS) approach, or bipolar ablation. In three patients who underwent tricuspid VS, successful RFCA was achieved using the above-prosthetics or trans-prosthetics approach. In two patients, RFCA failed. The trans-prosthetics approach and bipolar ablation technique were effective. The transaortic and CS approaches were occasionally effective. The transseptal approach was ineffective. CONCLUSIONS: Successful RFCA of APs at the site of prior VS can be achieved by detailed mapping of the areas both above and below the prosthetic valve, as well as by ensuring effective radiofrequency energy delivery using various catheter approaches and RFCA techniques.

Atrial Fibrillation Catheter Ablation Increases the Left Atrial Pressure.

BACKGROUND: We previously reported that a high left atrial (LA) pressure is associated with LA stiffness and poor rhythm outcomes after de novo catheter ablation of atrial fibrillation. Herein, we investigated whether radiofrequency catheter ablation generally changes the LA pressure among patients undergoing repeat procedures. METHODS: Among 1848 patients who underwent atrial fibrillation catheter ablation, we measured the LA pressure during sinus rhythm in 1687 patients before the de novo ablation (59±11 years, 72.4% men, 72.8% paroxysmal atrial fibrillation) and in 142 with second procedures. We measured the LA pressure immediately after the transseptal puncture at the beginning of the procedure. RESULTS: In the same 142 patients, the degree of LA stiffness, reflected by the LA pulse pressure (LApp), was significantly higher in the second procedure than in the de novo procedure ( P<0.001). The degree of the LApp increase (ΔLApp) was significantly higher in patients who underwent additional extrapulmonary vein LA ablation than in those who underwent circumferential pulmonary vein isolation alone ( P=0.010). Extrapulmonary vein LA ablation was independently associated with the ΔLApp (ß=5.70 [0.12-11.27]; P=0.045). An increased LApp during repeat procedures was independently associated with a reduced diastolic function (ß=2.01 [0.08-3.93]; P=0.041) without a worsening symptoms (EuroQol-five dimensions) score, 22.2±17.9 months after the de novo ablation. CONCLUSIONS: Atrial fibrillation catheter ablation, especially extrapulmonary vein LA ablation, increased the LA stiffness and was associated with a worsening postablation diastolic function. However, the symptom score did not significantly change. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov . Unique identifier: NCT02138695.

Novel method for the prediction of para-Hisian premature ventricular complexes from the electrocardiogram.

BACKGROUND: Catheter ablation of para-Hisian (PH) premature ventricular complexes (PVCs) has a high risk of heart block. This study aimed to find the electrocardiographic (ECG) predictors of PH-PVCs. METHODS: We enrolled 47 patients who underwent an electrophysiologic study for catheter ablation of PVCs and analyzed the ECG characteristics, retrospectively. RESULTS: The PVC locations were the PH in 14, right ventricular (RV) outflow tract (OT) in 11, left ventricular (LV) OT in 16, LV septum in 5, and LV summit in 1. The QRS width of the PH-PVCs was significantly narrower than that of the rest of PVCs (140.9 ± 17.1 ms vs. 158.9 ± 19.4 ms, P = 0.004). Precordial transition of the PH-PVCs related to sinus rhythm was not helpful in predicting the location. Lead I had monophasic R waves in 100% and lead aVR QS waves in 100%. In aVL, 13 of 14 patients had monophasic R waves, and 1 had biphasic (rS) waves with an initial positive polarity. Among the study cohort, 15 patients had a QS in aVR and R in aVL, including 13 PH-PVCs and 2 PVCs coming from the RVOT septum and LVOT septum, respectively. The QS in aVR and monophasic R in aVL had a sensitivity of 92.8%, specificity of 93.9%, positive predictive value of 86.7%, and negative predictive value of 96.9% for localizing PH-PVCs. CONCLUSIONS: A PVC morphology with a QS in aVR and monophasic R in aVL and QRS width <143 msec, could be used as a reliable parameter for predicting the PH location.

Efficacy and Safety of X-incision with Inversed Morcellation in Holmium Laser Enucleation of the Prostate: Comparison to Conventional Morcellation.

BACKGROUND: Three-quarters of aged men experience lower urinary tract symptoms with benign prostate hypertrophy (BPH). Transurethral resection of the prostate (TURP) and holmium laser enucleation of the prostate (HoLEP) are standard endosurgical procedures in patients with BPH. Previous studies reported better results in patients undergoing HoLEP than in those undergoing TURP. METHODS: This study compared the efficiency and safety of conventional morcellation and morcellation performed after X-incision during enucleation, a newly added technique in HoLEP. Overall, 174 patients were selected as the final study population. The populations were stratified with respect to resected volumes. A t-test were used to compare the conventional morcellation and X-incision procedure groups. RESULTS: In morcellation times and rates, there were significant differences in stratified resected mass (g) between the groups. The results also showed a decreased incidence of bladder injury as a surgical complication. CONCLUSION: We believe morcellation performed after X-incision procedure during enucleation is efficient and safe for older adults with BPH.

Influence of Sex on the Association Between Epicardial Adipose Tissue and Left Atrial Transport Function in Patients With Atrial Fibrillation: A Multislice Computed Tomography Study.

BACKGROUND: Epicardial adipose tissue (EAT) is known to play an important role in atrial fibrillation substrate remodeling; however, the influence of sex on the association between EAT and left atrial (LA) transport function has not been elucidated. METHODS AND RESULTS: Of the 514 patients who underwent an index atrial fibrillation ablation procedure, 123 postmenopausal women with no history of hormone replacement therapy and 123 men who were matched for age, body mass index, type of atrial fibrillation, and CHADS2 score were enrolled. Before the procedure, LA volume, LA emptying fraction, and EAT volume were assessed using multislice computed tomography. Blood samples were obtained from a coronary sinus for analysis of serum adiponectin level before the ablation procedure. There were no differences in baseline demographics and laboratory findings between sexes. Compared with men, women had significantly less total EAT (P<0.001) and higher serum adiponectin levels (P=0.022) but higher proportions of periatrial EAT to total EAT volume (P/T EAT ratio, P<0.001), lower LA emptying fraction (P=0.042), and lower LA voltage (P=0.034). The ratio of periatrial to total EAT volume correlated significantly with LA emptying fraction and LA voltage in both sexes, whereas total EAT volume and serum adiponectin level did not. On multivariate analysis, increased LA volume and higher periatrial:total EAT volume ratio were independent predictors of decreased LA emptying fraction in both sexes. CONCLUSIONS: Compared with matched men, postmenopausal women with atrial fibrillation had higher periatrial adiposity, which was independently correlated with decreased LA voltage and LA transport function.

Changes in Left Atrial Transport Function in Patients Who Maintained Sinus Rhythm After Successful Radiofrequency Catheter Ablation for Atrial Fibrillation: A 1-Year Follow-Up Multislice Computed Tomography Study.

BACKGROUND: Functional remodeling of left atrium (LA) after radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF) has not been fully elucidated. This study aimed to determine the impact of RFCA on LA transport function in patients who maintained sinus rhythm (SR) after AF ablation. METHODS AND RESULTS: A total of 96 patients (paroxysmal AF [PAF] = 52) who maintained SR during 1 year after AF ablation were enrolled. Multislice computed tomography was performed to determine LA volume (LAV) and LA emptying fraction (LAEF) at pre-RFCA and 1-year post-RFCA. Creatine kinase-MB (CK-MB) and troponin-T levels were analyzed 1-day post-RFCA. At 1-year post-RFCA, mean LAV and LAEF decreased in overall patients. Based on LAEF change (ΔLAEF) cutoff of 5.0%, LAEF reduced in 41 patients (worsened group) and improved or showed no change in 55 patients (preserved group). Compared with preserved group, worsened group had a higher proportion of PAF, higher levels of CK-MB and troponin-T, and additional LA ablation. ΔLAEF was inversely correlated with CK-MB and troponin-T levels. Subgroup analysis showed that LAEF significantly decreased in PAF patients who underwent additional LA ablation. Multivariate analysis revealed that high baseline LAEF and additional LA ablation were independent predictors for worsened LAEF. CONCLUSIONS: Although SR was maintained for 1 year after AF ablation, LAEF as well as LAV decreased. The extent of LAEF deterioration was significantly associated with the amount of iatrogenic myocardial damage. Our data indicate that extensive atrial ablation may lead to LA functional deterioration, especially in patients with PAF.

Safe Finger Tourniquet--Ideas.

Tourniquets are often needed for optimized phalangeal surgeries. However, few surgeons forget to remove them and caused ischemic injuries. We have a modified method to create a safe finger tourniquet for short duration finger surgeries, which can avoid such tragedy. It is done by donning a glove, cutting the tip of the glove over the finger of interest, and rolling the glove finger to the base. From 2010 to 2013, approximately 54 patients underwent digital surgical procedures with our safe finger tourniquet. Because the glove cannot be forgotten to be removed, the tourniquet must be released and removed. This is a simple and efficient way to apply a safe finger tourniquet by using hand rubber glove for a short-term bloodless finger surgery and can achieve an excellent surgical result.

Low Left Atrial Compliance Contributes to the Clinical Recurrence of Atrial Fibrillation after Catheter Ablation in Patients with Structurally and Functionally Normal Heart.

Stiff left atrial (LA) syndrome was initially reported in post-cardiac surgery patients and known to be associated with low LA compliance. We investigated the physiological and clinical implications of LA compliance by estimating LA pulse pressure (LApp) among patients with atrial fibrillation (AF) and structurally and functionally normal heart. Among 1038 consecutive patients with LA pressure measurements before AF ablation, we included 334 patients with structurally and functionally normal heart (81.7% male, 54.1±10.6 years, 77.0% paroxysmal AF) after excluding those with hypertension, diabetes, and previous ablation or cardiac surgery. We measured LApp (peak-nadir LA pressure) at the beginning of the ablation procedure and compared the values with clinical parameters and the AF recurrence rate. AF patients with normal heart were younger and more frequently male and had paroxysmal AF, a lower body mass index, and a lower LApp compared to others (all p<0.05). Based on the median value, the low LA compliance group (LApp≥13 mmHg) had a smaller LA volume index and lower LA voltage (all p<0.05) compared to the high LA compliance group. During a mean follow-up of 16.7±11.8 months, low LA compliance was independently associated with two fold-higher risk of clinical AF recurrence (HR:2.202; 95%CI:1.077-4.503; p = 0.031). Low LA compliance, as determined by an elevated LApp, was associated with a smaller LA volume index and lower LA voltage and independently associated with higher clinical recurrence after catheter ablation in AF patients with structurally and functionally normal heart.

Interatrial septal thickness as a marker of structural and functional remodeling of the left atrium in patients with atrial fibrillation.

BACKGROUND/AIMS: There have been reports that interatrial septal (IAS) thickness is increased in patients with atrial fibrillation (AF). This study was performed to investigate whether IAS thickness determined by transthoracic echocardiography (TTE) represents the amount of left atrium (LA) structural and functional remodeling. METHODS: The study population consisted of 104 consecutive patients who underwent catheter ablation (CA) for AF (paroxysmal atrial fibrillation [PAF], 82; persistent atrial fibrillation [PeAF], 22). IAS thickness and left atrium volume (LAV) using TTE, and LA voltage (LA(VOL)) using 3-dimensional electroanatomical mapping system were assessed during sinus rhythm. RESULTS: IAS thickness was significantly correlated with maximal LAV (LAV(max)) (r = 0.288, p = 0.003), mean LA(VOL) (r = -0.537, p < 0.001), total left atrium emptying fraction (LAEF(total); r = -0.213, p = 0.030), and active LAEF (LAEF(active); r = -0.249, p = 0.014). IAS thickness was greater in the high-risk group (≥ 2) compared to other groups according to CHA2DS2-VASc score (p = 0.019). During a follow-up of 19.6 months, 23 subjects (22.1%; PAF, 17; PeAF, 6) had recurrence of arrhythmia. Univariate analysis showed that LAV(max), minimal LAV, mean LA(VOL), LVEF(total), LVEF(active), and IAS thickness were associated with recurrence of arrhythmia. However, on multivariate analysis, only mean LA(VOL) and LAEF(active) were independent risk factors for recurrence. CONCLUSIONS: Although IAS thickness showed significant correlations with parameters for LA structural and functional remodeling, this parameter alone could not independently predict recurrence of arrhythmia after CA for AF.