Remote dielectric sensing predicts elevated left atrial pressure in patients with atrial fibrillation.

Background: There are currently no established non-invasive indices of echocardiography for elevated left atrial pressure (LAP) especially in patients with atrial fibrillation (AF). Remote dielectric sensing (ReDS) is a novel non-invasive electromagnetic energy-based technology that quantifies total lung fluid, enabling the monitoring of volume status in patients with heart failure. The utility of ReDS for estimating LAP in patients with AF remains unknown. Methods: We prospectively investigated patients with AF in whom LAP was directly measured during catheter ablation for AF, and ReDS measurements were conducted the day before ablation. Elevated LAP was defined as LAP ≥ 15 mmHg. Results: A total of 61 patients were included (median age 66 years, 38 % female). Among them, 26 patients had elevated LAP. There was a positive correlation between ReDS and LAP (r = 0.363, P = 0.004). Receiver operating characteristic curve analysis for the prediction of elevated LAP demonstrated that the best cut-off value of ReDS was 30 %, with a sensitivity of 65 %, specificity of 69 %, and an area under the curve of 0.703 (95 % confidence interval 0.568-0.837). Multivariate logistic regression analysis revealed that ReDS was an independent predictor of elevated LAP, among covariates including left ventricular ejection fraction, the ratio of early transmitral flow velocity to septal mitral annular early diastolic velocity, and left atrial volume index. Conclusions: Our results suggest ReDS could be a valuable marker of elevated LAP even in patients with AF. Further studies are needed to elucidate the effectiveness of a ReDS-guided decongestive strategy in patients with heart failure.

Electric field envelope focality in superficial brain areas with linear alignment montage in temporal interference stimulation.

Temporal interference stimulation (TIS) uses two pairs of conventional transcranial alternating current stimulation (tACS) electrodes, each with a different frequency, to generate a time-varying electric field (EF) envelope (EFE). The EFE focality in primary somatosensory and motor cortex areas of a standard human brain was computed using newly defined linear alignment montages. Sixty head volume conductor models constructed from magnetic resonance images were considered to evaluate interindividual variability. Six TIS and two tACS electrode montages were considered, including linear and rectangular alignments. EFEs were computed using the scalar-potential finite-difference method. The computed EFE was projected onto the standard brain space for each montage. Computational results showed that TIS and tACS generated different EFE and EF distributions in postcentral and precentral gyri regions. For TIS, the EFE amplitude in the target areas had lower variability than the EF strength of tACS. However, bipolar tACS montages showed higher focality in the superficial postcentral and precentral gyri regions than in TIS. TIS generated greater EFE penetration than bipolar tACS at depths <5-10 mm below the brain surface. From group-level analysis, tACS with a bipolar montage was preferred for targets <5-10 mm in depth (gyral crowns) and TIS for deeper targets. TIS with a linear alignment montage could be an effective method for deep structures and sulcal walls. These findings provide valuable insights into the choice of TIS and tACS for stimulating specific brain regions.

Utility of RAND/UCLA appropriateness method in validating multiple-choice questions on ECG.

OBJECTIVES: This study aimed to investigate the utility of the RAND/UCLA appropriateness method (RAM) in validating expert consensus-based multiple-choice questions (MCQs) on electrocardiogram (ECG). METHODS: According to the RAM user's manual, nine panelists comprising various experts who routinely handle ECGs were asked to reach a consensus in three phases: a preparatory phase (round 0), an online test phase (round 1), and a face-to-face expert panel meeting (round 2). In round 0, the objectives and future timeline of the study were elucidated to the nine expert panelists with a summary of relevant literature. In round 1, 100 ECG questions prepared by two skilled cardiologists were answered, and the success rate was calculated by dividing the number of correct answers by 9. Furthermore, the questions were stratified into "Appropriate," "Discussion," or "Inappropriate" according to the median score and interquartile range (IQR) of appropriateness rating by nine panelists. In round 2, the validity of the 100 ECG questions was discussed in an expert panel meeting according to the results of round 1 and finally reassessed as "Appropriate," "Candidate," "Revision," and "Defer." RESULTS: In round 1 results, the average success rate of the nine experts was 0.89. Using the median score and IQR, 54 questions were classified as " Discussion." In the expert panel meeting in round 2, 23% of the original 100 questions was ultimately deemed inappropriate, although they had been prepared by two skilled cardiologists. Most of the 46 questions categorized as "Appropriate" using the median score and IQR in round 1 were considered "Appropriate" even after round 2 (44/46, 95.7%). CONCLUSIONS: The use of the median score and IQR allowed for a more objective determination of question validity. The RAM may help select appropriate questions, contributing to the preparation of higher-quality tests.

A cost-effectiveness analysis of remote monitoring after pacemaker implantation for bradycardia in Japan.

BACKGROUND: Although remote monitoring (RM) after pacemaker implantation is common, its cost-effectiveness has not been fully investigated. Therefore, we assessed the cost-effectiveness of RM compared with conventional follow-up (CFU) in Japanese patients with pacemakers. METHODS: A Markov model was constructed to analyze costs and quality-adjusted life years after pacemaker implantation. The target population was Japanese patients implanted with a dual-chamber pacemaker for bradycardia. Transition probabilities (e.g. atrial fibrillation, stroke, and device trouble) were obtained from literature and expert sources. Additionally, stroke risk was determined according to anticoagulation and CHADS2 scores. We used a 10-year horizon with sensitivity analyses for significant variables. RESULTS: Compared to CFU, RM was more effective; however, it was also more expensive. When the range of the Japanese willingness-to-pay threshold was considered to be ¥5,000,000, RM was at least cost-neutral relative to the CFU in all elderly patients with pacemakers for bradycardia. The cost-effectiveness of RM relative to CFU could be higher for patients with high CHADS2 scores, especially in patients with a CHADS2 score ≥ 3. Scenario analyses changing the interval between visits to an in-office evaluation in the CFU also demonstrated the same conclusions. In particular, when the interval between office visits was 1 year for the CFU, the RM could be more cost-effective. CONCLUSIONS: This study demonstrated that RM can be a cost-effective option for Japanese patients, especially those with high CHADS2 scores and long-term intervals between office visits.

Automated categorization of virtual reality studies in cardiology based on the device usage: a bibliometric analysis (2010-2022).

Aims: Currently, virtual reality (VR) constitutes a vital aspect of digital health, necessitating an overview of study trends. We classified type A studies as those in which health care providers utilized VR devices and type B studies as those in which patients employed the devices. This study aimed to analyse the characteristics of each type of studies using natural language processing (NLP) methods. Methods and results: Literature related to VR in cardiovascular research was searched in PubMed between 2010 and 2022. The characteristics of studies were analysed based on their classification as type A or type B. Abstracts of the studies were used as corpus for text mining. A binary logistic regression model was trained to automatically categorize the abstracts into the two study types. Classification performance was evaluated by accuracy, precision, recall, F-1 score, and c-statistics of the receiver operator curve (ROC) analysis. In total, 171 articles met the inclusion criteria, where 120 (70.2%) were type A studies and 51 (29.8%) were type B studies. Type A studies had a higher proportion of case reports than type B studies (18.3% vs. 3.9%, P = 0.01). As for abstract classification, the binary logistic regression model yielded 88% accuracy and an area under the ROC of 0.98. The words 'training', '3d', and 'simulation' were the most powerful determinants of type A studies, while the words 'patients', 'anxiety', and 'rehabilitation' were more indicative for type B studies. Conclusions: NLP methods revealed the characteristics of the two types of VR-related research in cardiology.

Premature atrial contraction immediately after catheter ablation was associated with late recurrence of atrial fibrillation.

BACKGROUND: Although premature atrial contractions (PACs) just after catheter ablation (CA) for atrial fibrillation (AF) are common, their clinical significance is uncertain. This study aimed to evaluate whether the PAC burden after an initial CA for AF was associated with late recurrence. METHODS: We enrolled 346 patients with AF (median age, 65 years; 30% female; 57% with paroxysmal AF) who underwent an initial radiofrequency CA and a 24-h Holter monitoring the day after the procedure. PAC was defined as supraventricular complexes occurring ≥30% earlier than expected compared with a previous RR interval, and the number of PAC/24 h during post-procedural Holter monitoring was analyzed. RESULTS: AF recurred in 106 patients (31%) during a median follow-up of 19 months. These patients had significantly more PAC/24 h than those without (median [interquartile range], 891 [316-4351] beats vs. 409 [162-1,303] beats; p < 0.01). The number of PACs was independently associated with AF recurrence after adjustment for clinical parameters and left atrial (LA) enlargement. Receiver operating characteristic (ROC) curve analysis revealed that 1431 PAC/24 h was the optimal cut-off value for predicting AF recurrence. Adding the PAC/24 h to the prediction model with LA diameter appeared to correctly reclassify patients who were thought to be at high risk for AF recurrence into the low-risk group and vice versa. CONCLUSIONS: The number of PACs was an independent risk factor for AF recurrence. A 24-h Holter recording the day after an initial CA is a simple and beneficial tool for the risk stratification of AF recurrence.

Is the QRS duration useful for determining the optimal timing of pulmonary valve replacement after tetralogy of Fallot repair?

OBJECTIVES: In pulmonary valve replacement (PVR) after tetralogy of Fallot (TOF) repair, the right ventricular end-diastolic and end-systolic volume index (RVEDVI and RVESVI) of cardiac magnetic resonance imaging (cMRI) are often used as indicators of the RV volume. We examined the utility of QRS duration, cardiothoracic ratio (CTR), and plasma brain natriuretic peptide (BNP) as indicators of the appropriate timing of cMRI to assess the RV volume and function before PVR. METHODS: We assessed the correlation of QRS duration, CTR, and BNP with RVEDVI and RVESVI on cMRI in 26 patients after TOF repair. Fifteen underwent PVR (age, 45.2 ± 11.4 years). Twelve underwent post-PVR cMRI. The RV volume change from before to after PVR was investigated. RESULTS: QRS duration, BNP, and CTR were positively correlated with RVEDVI and RVESVI after TOF repair. The post-PVR QRS duration was also positively correlated with post-PVR RVEDVI (p = 0.017) and RVESVI (p = 0.001). From before to after PVR, in 5 cases with QRS duration ≤ 160 ms, the QRS duration decreased from 110.4 ± 28.9 to 101.8 ± 30.5 ms (p = 0.063). Both RVEDVI and RVESVI decreased to the normal range in 4 of 5 cases. In contrast, in 7 cases with QRS duration > 160 ms, the QRS duration decreased from 183.0 ± 17.4 to 160.3 ± 23.8 ms (p = 0.013); however, RVESVI did not normalize in 6 of 7 cases. CONCLUSIONS: A prolonged QRS duration is a useful marker of RVEDVI and RVESVI enlargement after TOF repair. We recommend performing cMRI before the QRS duration reaches 160 ms due to normalization of the RV volume after PVR.

Status of adult outpatients with congenital heart disease in Japan: The Japanese Network of Cardiovascular Departments for Adult Congenital Heart Disease Registry.

BACKGROUND: The Japanese Network of Cardiovascular Departments for Adult Congenital Heart Disease (JNCVD-ACHD) was founded in 2011 for the lifelong care of adult patients with congenital heart disease (ACHD patients). This network maintains the first Japanese ACHD registry. METHODS AND RESULTS: From 2011 to 2019, the JNCVD-ACHD registered 54 institutions providing specialized care for ACHD patients in 32 of the 47 prefectures in Japan. The registry collected data on the disease profile for 24,048 patients from 50 institutions and the patient characteristics for 9743 patients from 24 institutions. The most common ACHDs were atrial septal defect (20.5 %), ventricular septal defect (20.5 %), tetralogy of Fallot (12.9 %), and univentricular heart (UVH)/single ventricle (SV; 6.6 %). ACHD patients without biventricular repair accounted for 37.0 % of the population. Also examined were the serious anatomical and/or pathophysiological disorders such as pulmonary arterial hypertension (3.0 %) including Eisenmenger syndrome (1.2 %), systemic right ventricle under biventricular circulation (sRV-2VC; 2.8 %), and Fontan physiology (6.0 %). The sRV-2VC cases comprised congenitally corrected transposition of the great arteries without anatomical repair (61.9 %) and transposition of the great arteries with atrial switching surgery (38.1 %). The primary etiology (86.4 %) for Fontan physiology was UVH/SV. In addition, developmental/chromosomal/genetic disorders were heterotaxy syndromes (asplenia, 0.9 %; polysplenia, 0.7 %), trisomy 21 (4.0 %), 22q11.2 deletion (0.9 %), Turner syndrome (0.2 %), and Marfan syndrome (1.1 %). CONCLUSIONS: Although the specific management of ACHD has systematically progressed in Japan, this approach is still evolving. For ideal ACHD care, the prospective goals for the JNCVD-ACHD are to create local networks and provide a resource for multicenter clinical trials to support evidence-based practice.

Transvenous pacing approach for atrioventricular block in fontan - Possibility of transvenous approach by electrophysiological assessment.

In extracardiac Fontan, an epicardial pacemaker implantation has many limitations, especially given that it is highly invasive and a high-risk procedure due to repeat thoracotomy. Herein we illustrate a case with the possibility of transvenous pacing in extracardiac Fontan being less invasive and lower risk transvenous dual-chamber pacemaker implantation by electrophysiological assessment. .

Echocardiographic Assessment of Atrial Function: From Basic Mechanics to Specific Cardiac Diseases.

The left and right atria serve as buffer chambers to control the flow of venous blood for ventricular filling. If an atrium is absent, blood does not flow effectively into the ventricle, leading to venous blood retention and low cardiac output. The importance of atrial function has become increasingly recognized, because left atrial (LA) function contributes to cardiac performance, and loss of LA function is associated with heart failure. LA volume change has been used for LA function assessment in experimental and clinical studies. In conjunction with LA pressure, the LA pressure-volume relationship provides a better understanding of LA mechanics. LA strain measurement by speckle tracking echocardiography was introduced to evaluate three components of LA function as a (booster) pump, reservoir and conduit. Furthermore, increasing evidence supports the theory that LA reservoir strain has prognostic utility in various cardiac diseases. In this review, we summarize LA contribution to maintain cardiac performance by evaluating LA function with echocardiography according to our experiences and previous reports. Furthermore, we discuss LA dysfunction in challenging cardiac diseases of cardiac amyloidosis and adult congenital heart disease.

Restricted left atrial dilatation can visually differentiate cardiac amyloidosis from hypertrophic cardiomyopathy.

AIMS: Cardiac amyloidosis (CA) is an infiltrative myocardial disease that occasionally mimics hypertrophic cardiomyopathy (HCM). The aim of this study is to investigate the discriminatory ability of visual assessment of left atrial (LA) function between CA and HCM on echocardiography. METHODS AND RESULTS: In total, 93 patients with cardiac magnetic resonance imaging (CMR)-confirmed HCM and 34 with cardiac biopsy-confirmed CA were retrospectively assessed. LA dilatation was assessed via echocardiography in an apical four-chamber view. Visual assessment was performed to identify LA dilatation grade (preserved = 1, abnormal = 2, and restricted = 3) based on the extent of outward expansion in the LA reservoir phase. Regarding the reproducibility of visually assessing LA dilatation grade, the kappa values between intra- and inter-observer measurements were 0.82 and 0.70, respectively. Of 127 participants, 57 (45%), 42 (33%), and 28 (22%) presented with LA dilatation Grades 1, 2, and 3, respectively. All 57 patients with preserved LA dilatation (Grade 1) had HCM, and 20 of 28 patients (71%) with restricted LA dilatation (Grade 3) presented with CA. Patients with CA had a higher LA dilatation grade than those with HCM (P < 0.01). LA emptying fraction and reservoir strain were also quantitatively evaluated. The area under the curves of LA dilatation grade (0.88) and LA emptying fraction (0.88) for differentiation of these two diseases were higher than that of LA reservoir strain (0.73) (P < 0.01, respectively). During follow-up, nine patients with HCM and 16 with CA experienced cardiac event (cardiac death or hospitalization due to heart failure). In Kaplan-Meier analysis including both groups of HCM and CA, the incidence of cardiac events was higher in patients with restricted LA dilatation than in those with preserved or abnormal LA dilatation (log-rank test, P < 0.01). CONCLUSIONS: Restricted LA dilatation is an indicator for the diagnosis of CA. Further, visual assessment of abnormal LA motion may facilitate diagnosis in patients with CA and high-risk patients with HCM.