Predictors of Water Turnover in Older Adults: A Doubly Labeled Water- and Triaxial Accelerometer-Based Study.

BACKGROUND: Water is one of the most essential nutrients for life. The water turnover (WT), total body water (TBW), and total energy expenditure (TEE) can be measured using the doubly labeled water (DLW) method. WT and TBW are lower in older adults than in young adults, and the former are susceptible to dehydration, necessitating to identify predictors of the WT in older adults. OBJECTIVES: The current study aimed to examine the association between WT and physical activity, physical function, and body composition in Japanese adults aged ≥65 y and identify predictors for WT in this population. METHODS: This study enrolled 133 older adults (women, n = 61; men, n = 72) aged 65-88 y. WT, TBW, TEE, fat-free mass (FFM), and percent body fat (%Fat) were determined using the DLW method. The fitness age score (FAS) was obtained from 5 physical fitness tests. Physical activity and the step count were assessed using a previously validated triaxial accelerometer. Multiple regression analyses were performed with WT as the dependent variable. RESULTS: WT was positively associated with weight, physical activity level (PAL), moderate-vigorous physical activity, and TEE, and negatively associated with sedentary behavior. We examined potential predictors for WT using age, sex, height, weight, FFM, %Fat, TEE, PAL, and FAS in older Japanese adults. CONCLUSIONS: Our results confirmed that age, sex, weight, FFM, TEE, and PAL are the potential predictors of WT in older Japanese adults aged ≥65 y.

Preoperative Prediction of Shock Impedance for Subcutaneous Implantable Cardioverter Defibrillator Using Chest Computed Tomography.

BACKGROUND: High shock impedance is associated with conversion failure among patients with subcutaneous implantable cardioverter defibrillators (S-ICD). Currently, there is no preoperative assessment method for predicting high shock impedance. This study examined the efficacy of chest computed tomography (CT) as a preoperative evaluation tool to assess the shock impedance of S-ICDs.Methods and Results: The amount of adipose tissue adjacent to the device and anteroposterior diameter at the basal heart region were measured preoperatively using chest CT. We examined the correlation between these measurements and shock impedance at the conversion test. We enrolled 43 patients with S-ICDs (mean [±SD] age 54±15 years; body mass index 23±4 kg/m2; PRAETORIAN score 30-270 points; amount of adipose tissue 1,250±716 cm3), who underwent intraoperative conversion tests by inducing ventricular fibrillation, which was terminated with a 65-J shock. A sufficient concordance correlation coefficient was observed between the shock impedance and the amount of adipose tissue (r=0.616, P<0.01) and anteroposterior diameter (r=0.645, P<0.01). In multiple regression analysis, the amount of adipose tissue (ß=0.439, P=0.009) and anteroposterior diameter (ß=0.344, P=0.038) were identified as independent predictive factors of shock impedance. CONCLUSIONS: The preoperative CT-measured amount of adipose tissue and basal heart anteroposterior diameter are independent predictors of shock impedance. These parameters may be more accurate in identifying higher shock impedance in patients with S-ICDs.

Effects of energy loads on energy and nutrient absorption rates and gut microbiome in humans: A randomized crossover trial.

OBJECTIVE: This study aimed to determine the effects of different energy loads on the gut microbiota composition and the rates of energy and nutrient excretion via feces and urine. METHODS: A randomized crossover dietary intervention study was conducted with three dietary conditions: overfeeding (OF), control (CON), and underfeeding (UF). Ten healthy men were subjected to each condition for 8 days (4 days and 3 nights in nonlaboratory and laboratory settings each). The effects of dietary conditions on energy excretion rates via feces and urine were assessed using a bomb calorimeter. RESULTS: Short-term energy loads dynamically altered the gut microbiota at the α-diversity (Shannon index), phylum, and genus levels (p < 0.05). Energy excretion rates via urine and urine plus feces decreased under OF more than under CON (urine -0.7%; p < 0.001, urine plus feces -1.9%; p = 0.049) and UF (urine -1.0%; p < 0.001, urine plus feces -2.1%; p = 0.031). However, energy excretion rates via feces did not differ between conditions. CONCLUSIONS: Although short-term overfeeding dynamically altered the gut microbiota composition, the energy excretion rate via feces was unaffected. Energy excretion rates via urine and urine plus feces were lower under OF than under CON and UF conditions.

Successful Epicardial Radiofrequency Ablation of Ventricular Tachycardia That Shared a Pathway with Bi-Directional Conduction in a Patient with Human Immunodeficiency Virus-Associated Cardiomyopathy.

A 59-year-old man who had been diagnosed with human immunodeficiency virus-associated cardiomyopathy was referred for catheter ablation of ventricular tachycardia (VT). An electrocardiogram (ECG) waveform revealed that the clinical VT originated from the epicardium. A deceleration zone (DZ) was identified on an isochronal late activation map. Moreover, 2 forms of monomorphic VT were induced by different cycle length burst pacings from near the DZ. The morphologies of the 2 VTs with an identical cycle length were very likely to use a shared common pathway with bi-directional conduction around the slow conduction area in the left ventricle posterolateral small epicardial surface area. After ablation of the DZ, the VT was uninducible.

Revisiting predictors of worse atrioventricular valve and left ventricular systolic function following pacemaker therapy.

BACKGROUND: Predictors of worsening atrioventricular valve regurgitation and left ventricular (LV) systolic function after implantation of a leadless pacemaker (LPM) remain unclear compared with those of a transvenous pacemaker (TPM). METHODS: We retrospectively analyzed 205 patients who were newly implanted with a permanent pacemaker (119 LPMs and 86 TPMs) and underwent transthoracic echocardiography before and 8 ± 5 months after implantation. We evaluated the worsening of tricuspid and mitral regurgitation (TR and MR), defined as at least one-grade aggravation in severity, and changes in LV ejection fraction (LVEF). RESULTS: Worsening TR occurred more frequently in the LPM group compared to the TPM group (33% vs. 20%, p = .04); however, there was no significant difference between the two groups regarding worsening MR (26% vs. 18%, p = .18) and LVEF change (-2 ± 10% vs. -3 ± 8%, p = .40). In multivariable analysis, independent predictors for worsening TR, MR, and LVEF after implantation were found to be (1) the change from sinus rhythm at baseline to atrioventricular asynchronous right ventricular (RV) pacing (odds ratio [OR]: 5.68, 95% confidence interval [CI]: 1.94-16.70, p < .01); (2) the change from non-pacing ventricular contraction at baseline to RV pacing (OR: 2.42, 95% CI: 1.12-5.24, p = .02); and (3) a higher RV pacing burden (ß: -0.05, 95% CI: -0.08--0.02, p < .01), respectively. CONCLUSION: Worsening TR, MR, and LVEF after pacemaker implantation were not associated with the type of pacing device but loss of atrioventricular synchrony or dependency on RV pacing.

Two-year Outcomes of Ventricular-demand Leadless Pacemaker Therapy for Heart Block After Transcatheter Aortic Valve Replacement.

Ventricular-demand leadless pacemakers (VVI-LPMs) have often been used as an alternative to atrioventricular (AV) synchronous transvenous pacemakers (DDD-TPMs) in patients with high-grade AV block following transcatheter aortic valve replacement (TAVR). However, the clinical outcomes of this unusual usage are not elucidated. Patients who received permanent pacemakers (PPMs) owing to new-onset high-grade AV block after TAVR from September 2017 to August 2020 at a high-volume center in Japan were included in the analysis, and the clinical courses of VVI-LPM and DDD-TPM implants through 2 years of follow-up were compared retrospectively. Out of 413 consecutive patients who underwent TAVR, 51 (12%) patients received a PPM. After excluding 8 patients with chronic atrial fibrillation (AF), 3 with sick sinus syndrome, and 1 with incomplete data, 17 VVI-LPMs and 22 DDD-TPMs were included in our final cohort. The VVI-LPM group had lower serum albumin levels (3.2 ± 0.5 vs. 3.9 ± 0.4 g/dL, P < .01) than the DDD-TPM group. Follow-up revealed no significant differences between the 2 groups in terms of the incidence of late device-related adverse events (0% vs. 5%, log-rank P = .38) and new-onset AF (6% vs. 9%, log-rank P = .75); however, there were increases in the rates of all-cause death (41% vs. 5%, log-rank P < .01) and heart failure rehospitalization (24% vs. 0%, log-rank P = .01) in the VVI-LPM group. This small retrospective study reveals favorable post-procedural complication rates but higher all-cause mortality with VVI-LPM compared to DDD-TPM therapy for high-grade AV block after TAVR at 2 years of follow-up.

Association between Intra- and Extra-Cellular Water Ratio Imbalance and Natriuretic Peptides in Patients Undergoing Hemodialysis.

Natriuretic peptides are associated with malnutrition and volume overload. Over-hydration cannot simply be explained by excess extracellular water in patients undergoing hemodialysis. We assessed the relationship between the extracellular and intracellular water (ECW/ICW) ratio, N-terminal pro-B-type natriuretic peptide (NT-proBNP), human atrial natriuretic peptide (hANP), and echocardiographic findings. Body composition was examined by segmental multi-frequency bioelectrical impedance analysis in 368 patients undergoing maintenance dialysis (261 men and 107 women; mean age, 65 ± 12 years). Patients with higher ECW/ICW ratio quartiles tended to be older, were on dialysis longer, and had higher post-dialysis blood pressure and lower body mass index, ultrafiltration volume, serum albumin, blood urea nitrogen, and creatinine levels (p < 0.05). The ECW/ICW ratio significantly increased with decreasing ICW, but not with ECW. Patients with a higher ECW/ICW ratio and lower percent fat had significantly higher natriuretic peptide levels. After adjusting for covariates, the ECW/ICW ratio remained an independent associated factor for natriuretic peptides (ß = 0.34, p < 0.001 for NT-proBNP and ß = 0.40, p < 0.001 for hANP) and the left ventricular mass index (ß = 0.20, p = 0.002). The ICW-ECW volume imbalance regulated by decreased cell mass may explain the reserve capacity for fluid accumulation in patients undergoing hemodialysis.

Regional Difference in the Impact of COVID-19 Pandemic on Domain-Specific Physical Activity, Sedentary Behavior, Sleeping Time, and Step Count: Web-Based Cross-sectional Nationwide Survey and Accelerometer-Based Observational Study.

BACKGROUND: Physical activity (PA) and sedentary behavior (SB) have been affected by the COVID-19 pandemic and its restrictive environments, such as social distancing and lockdown measures. However, regional differences in the changes in domain-specific PA and SB in response to the COVID-19 pandemic are not clearly understood. OBJECTIVE: This study aimed to examine regional differences in domain-specific PA and SB, as well as sleeping time in response to the COVID-19 pandemic in Japan. METHODS: A web-based cross-sectional nationwide survey and an accelerometer-based longitudinal observation were conducted. In the web-based survey, we recruited 150 Japanese men and 150 Japanese women for each of the following age groups: 20s, 30s, 40s, 50s, 60s, and 70s (n=1800). A total of 1627 adults provided valid responses to web-based surveillance from June to July 2020. Participants were recruited from urban (Greater Tokyo Area, n=1028), urban-rural (regional core cities, n=459), or rural (regional small and medium cities, n=140) areas. They answered sociodemographic and health-related questions and retrospectively registered the PA data of their average day before and during the COVID-19 pandemic in a web-based PA record system. In the accelerometer-based observation, PA and step count data were obtained using a triaxial accelerometer on people living in urban (n=370) and rural (n=308) areas. RESULTS: Before the COVID-19 pandemic, there were no significant differences between these 3 regions in the time spent sleeping, staying at home, working or studying, and exercising (P>.05). By contrast, people living in urban areas had a longer duration of SB and transportation and a shorter duration of moderate-to-vigorous PA and lying or napping time compared with people living in rural areas (P>.05). During the COVID-19 pandemic, a significant decrease was observed in transportation time in urban (-7.2 min/day, P<.001) and urban-rural (-2.0 min/day, P=.009) areas but not in rural (-0.4 min/day, P=.52) areas. The moderate-to-vigorous PA was decreased in urban (-31.3 min/day, P<.001) and urban-rural (-30.0 min/day, P<.001) areas but not in rural areas (-17.3 min/day, P=.08). A significant increase was observed in time spent sleeping in urban (+22.4 min/day, P<.001) and urban-rural (+24.2 min/day, P<.001) but not in rural areas (+3.9 min/day, P=.74). Lying or napping was increased in urban (+14.9 min/day, P<.001) but not in rural areas (-6.9 min/day, P=.68). PA and step count obtained using an accelerometer significantly decreased in urban (P<.05) but not in rural areas (P>.05). CONCLUSIONS: The effect of the COVID-19 pandemic on PA and SB was significantly dependent on living area, even in a single country. The effects of PA and SB were greater in the Greater Tokyo Area and regional core cities but were not observed in regional small and medium cities in Japan.

Clinical Outcomes of Non-Atrial Fibrillation Bradyarrhythmias Treated With a Ventricular Demand Leadless Pacemaker Compared With an Atrioventricular Synchronous Transvenous Pacemaker　- A Propensity Score-Matched Analysis.

BACKGROUND: Implanting a ventricular demand leadless pacemaker (VVI-LPM) for patients with non-atrial fibrillation (AF) bradyarrhythmias such as sick sinus syndrome (SSS) or high-grade (i.e., second- or third-degree) atrioventricular (AV) block is not recommended unless they have limited vascular access or a high infection risk; nevertheless, an unexpectedly high number of VVI-LPM implantations have been performed. This study investigated the clinical outcomes of these unusual uses.Methods and Results:This study retrospectively analyzed 193 patients who were newly implanted with a VVI-LPM or an atrioventricular synchronous transvenous pacemaker (DDD-TPM) for non-AF bradyarrhythmias at a high-volume center in Japan from September 2017 to September 2020. Propensity score-matching produced 2 comparable cohorts treated with a VVI-LPM or DDD-TPM (n=58 each). Each group had 20 (34%) patients with SSS and 38 (66%) patients with high-grade AV block. During a median follow up of 733 (interquartile range 395-997) days, there were no significant differences between the VVI-LPM and DDD-TPM groups regarding late device-related adverse events (0% vs. 4%, log-rank P=0.155), but the VVI-LPM group had a significantly increased readmission rate for heart failure (HF) (29% vs. 2%, log-rank P=0.001) and a tendency to have higher all-cause mortality (28% vs. 4%, log-rank P=0.059). CONCLUSIONS: The implantation of a VVI-LPM for non-AF bradyarrhythmias increased the incidence of HF-related rehospitalization at the mid-term follow up compared to the use of a DDD-TPM.

Evaluation of potential underuse of cardiac resynchronization therapy for heart failure with reduced ejection fraction.

BACKGROUND: The number of patients with chronic heart failure is increasing in Japan. However, the annual number of patients with heart failure who receive cardiac resynchronization therapy (CRT) has been constant in the last few years. In this study, we evaluated patients who did not receive CRT despite being eligible for this treatment to elucidate the clinical impact of CRT administration. METHODS: We assessed 214 patients with a left ventricular ejection fraction (LVEF) ≤ 50% (excluding patients treated with CRT) who underwent transthoracic echocardiography between January and May 2020 at our institution. The patients were stratified into two groups: Group A (n = 26; patients eligible for CRT) and Group B (n = 188; patients ineligible for CRT); however, all patients only received pharmacological therapy. We retrospectively analyzed the prognosis of these patients with respect to the cumulative number of hospitalizations for heart failure and cardiogenic deaths. RESULTS: We observed no significant between-group differences in age, sex, and severity/diagnosis of organic heart disease. Group A had a significantly higher number of hospitalizations for heart failure and cardiogenic deaths than Group B (log-rank test, P < .01; hazard ratio, 3.05; 95% confidence interval, 1.31-7.09; average follow-up period, 675 days). CONCLUSIONS: This study shows that 12% of patients were eligible for CRT. However, the implantation rate was low and no one was implanted. CRT is underutilized in patients who have heart failure with reduced LVEF. Therefore, we strongly recommend CRT for patients with indications for CRT.

Monomorphic ventricular tachycardia induced by tilt table testing in a patient with syncope and normal heart.

Ventricular tachycardia induced by tilt table testing.

Polymorphic Ventricular Tachycardia with QT Interval Prolongation Due to a Brain Tumor.

We herein report the case of a 20-year-old man with a history of epilepsy who presented with frequent transient loss of consciousness (T-LOC) and polymorphic ventricular tachycardia (VT) with QT interval prolongation. Blood investigations revealed panhypopituitarism. Following a biopsy, he was diagnosed with brain germinoma. During the biopsy, he had an episode of polymorphous VT with QT prolongation. There was no recurrence of T-LOC following chemotherapy and hormone replacement therapy. This case indicates the importance of checking the QT interval in patients with T-LOC, including those with seizures and brain tumors, to ensure appropriate treatment.

Feasibility of kissing balloon technique through guide extension catheters: an experimental bench test.

Previous reports showed that GuideLiner (GL) and Guidezilla (GZ) can accommodate bulky and multiple devices beyond the official profiles. However, feasibility of kissing balloon technique (KBT) through these devices is unknown. The tested devices included 7Fr-GL/GZ and respective three types of 2.5 mm semi-compliant (SC) and non-compliant (NC) balloons: conventional model (CM), tapered-tip model (TM) and latest model (LM). First, three experienced operators attempted to advance all 21 combinations of the 2 balloons through GL/GZ on the guidewires and assessed the crossability in 3 grades: easy, difficult and impossible. Second, the only balloon combinations graded as easy by all operators were tested in the polyurethane-made bifurcation model which required KBT following cross-over stenting. Within the total of 42 device combinations, only one balloon combination of double LM-NC balloons was classified as easy in both GL/GZ by consensus opinion of the operators. While two combinations of LM-SC and LM-SC/NC balloons were classified as difficult in both GL/GZ, all four combinations of LM-SC/NC and CM/TM-NC balloons were classified as difficult only in GL. Other 32 combinations were all classified as impossible. In the bifurcation model, the combination of double LM-NC balloons using GL achieved KBT while the same balloon combination with GZ failed. The feasibility of KBT using child-catheter is highly dependent on the device characteristics. The combination of latest small-profile NC balloons through GL could be clinically applicable.

Interference Between Pressure-Wire and Deployed Coronary Stents: Insights from a Bench Test.

BACKGROUND: While several complications related to pressure-wire (PW) have been reported, mechanistic justification has not always been offered. Furthermore, interference between a PW and a protruding side-branch stent has not been previously reported. The purpose of this study was to evaluate interference between PW-pullback from a main-branch with a protruded ostial stent deployed in a side-branch. METHODS: In a polyurethane bifurcation vessel model, PW-pullback was performed in a main-branch following protruded ostial stenting in a side-branch. Tested PWs included PressureWire X, Comet, OptoWire, and Verrata. For each PW, pullback was performed through the same proximal cell of the protruded stent 20 times. Interference during PW-pullback was objectively analyzed with a fiberscope placed at the distal main-branch and classified into 3 grades according to the interaction with stent strut. RESULTS: There were significant differences in the rate of interference between the PWs. No-interference, interference without strut traction, and interference with strut traction (i.e. stent deformation) were observed as follows: 17/20, 3/20, and 0/20 in PressureWire X; 19/20, 1/20, and 0/20 in Comet; 8/20, 10/20, and 2/20 in OptoWire; and 13/20, 2/20, and 5/20 in Verrata, respectively (p for any differences: <0.001). Visually identifiable major stent deformation was observed once in OptoWire due to the deep concave sensor window and twice in Verrata due to the proximal gap between the sensor and coiled-wire. CONCLUSIONS: PW-pullback in the main-branch after side-branch ostial stenting should be carefully performed to avoid stent deformation. Consideration on the specific mechanical features of the PW is also essential.

Novel Device-Based Algorithm Provides Optimal Hemodynamics During Exercise in Patients With Cardiac Resynchronization Therapy.

BACKGROUND: An adaptive cardiac resynchronization therapy (aCRT) algorithm has been described for synchronized left ventricular (LV) pacing and continuous optimization of cardiac resynchronization therapy (CRT). However, there are few algorithmic data on the effect of changes during exercise.Methods and Results:We enrolled 27 patients with availability of the aCRT algorithm. Eligible patients were manually programmed to optimal atrioventricular (AV) and interventricular (VV) delays by using echocardiograms at rest or during 2 stages of supine bicycle exercise. We compared the maximum cardiac output between manual echo-optimization and aCRT-on during each phase. After initiating exercise, the optimal AV delay progressively shortened (P<0.05) with incremental exercise levels. The manual-optimized settings and aCRT resulted in similar cardiac performance, as demonstrated by a high concordance correlation coefficient between the LV outflow tract velocity time integral (LVOT-VTI) during each exercise stage (Ex.1: r=0.94 P<0.0008, Ex.2: r=0.88 P<0.001, respectively). Synchronized LV-only pacing in patients with normal AV conduction could provide a higher LVOT-VTI as compared with manual-optimized conventional biventricular pacing at peak exercise (P<0.05). CONCLUSIONS: The aCRT algorithm was physiologically sound during exercise by patients.

Monitoring free flap venous congestion using continuous tissue glucose monitoring: A case report.

Blood glucose levels (BGLs) are a good indicator of postoperative venous congestion caused by a thrombus at the anastomotic site of a free flap. Tissue glucose levels (TGLs) are believed to be superior to BGLs for two reasons: TGLs are thought to represent a tissue's congestive status more directly than BGLs and are able to be measured by a continuous tissue glucose monitoring device (CTGMD), whereas BGLs must be measured manually by sampling the flap, hindering the patient's sleep and increasing the nurse's workload. A case is described in which a postoperative thrombus developed in a free flap vein three times. TGL in the flap was monitored by a CTGMD (Free Style Libre®, Abbott, U.S.A.), and BGL was monitored in parallel by conventional sampling of the flap. When venous congestion developed at the anastomotic site, TGLs decreased faster than BGLs; after the congestion was ameliorated by exsanguination, BGLs increased faster than TGLs, indicating that TGLs are a better indicator of venous thrombosis at the anastomotic site than BGLs.

Cerebrospinal Fluid Biomarkers for Kii Amyotrophic Lateral Sclerosis/Parkinsonism-Dementia Complex.

Objective. Amyotrophic lateral sclerosis/parkinsonism-dementia complex is classified as one of the tauopathies. Methods. The total tau, phosphorylated tau, and amyloid ß42 levels were assayed in cerebrospinal fluid from patients with Kii amyotrophic lateral sclerosis/parkinsonism-dementia complex (n = 12), Alzheimer's disease (n = 9), Parkinson's disease (n = 9), amyotrophic lateral sclerosis (n = 11), and controls (n = 5) using specific enzyme-linked immunosorbent assay methods. Results. Total tau and phosphorylated tau did not increase and amyloid ß42 was relatively reduced in Kii amyotrophic lateral sclerosis/parkinsonism-dementia complex. Relatively reduced amyloid ß42 might discriminate Kii amyotrophic lateral sclerosis/parkinsonism-dementia complex from amyotrophic lateral sclerosis and Parkinson's disease, and the ratios of phosphorylated-tau to amyloid ß42 could discriminate Kii amyotrophic lateral sclerosis/parkinsonism-dementia complex from Alzheimer's disease. Conclusions. Cerebrospinal fluid analysis may be useful to differentiate amyotrophic lateral sclerosis/parkinsonism-dementia complex from Alzheimer's disease, amyotrophic lateral sclerosis, and Parkinson's disease.