Predictive value of early-phase heart rate reduction for subsequent recovery of left ventricular systolic function in heart failure with reduced ejection fraction.

INTRODUCTION: Predictors of heart failure with recovered ejection fraction (HFrecEF) remain to be fully elucidated. This study investigated the impact of heart rate and its change on the recovery of left ventricular ejection fraction (LVEF) in heart failure with reduced ejection fraction (HFrEF). MATERIAL AND METHODS: From 398 outpatients who had a history of hospitalisation for heart failure, 138 subjects diagnosed as HFrEF (LVEF < 40%) on heart failure hospitalisation were enrolled and longitudinally surveyed. During follow-up periods more than one year, 64 and 46 patients were identified as HFrecEF (improved LVEF to ≥ 40% and its increase of ≥ 10 points) and persistent HFrEF, respectively. RESULTS: In the overall subjects, the reduction of heart rate through the observation periods was closely correlated with the improvement of LVEF (r = -0.508, p < 0.001). Heart rate on hospital admission for heart failure was markedly higher in patients with HFrecEF (112 ± 26 bpm) than in those with persistent HFrEF (90±18 bpm). Whereas heart rate at the first outpatient visit after discharge was already lower in the HFrecEF group (80 ± 13 vs. 85 ± 13 bpm in the persistent HFrEF group). A multivariate logistic regression analysis revealed that the decrease in heart rate from admission to the first visit after discharge was a significant determinant of HFrecEF (p < 0.001), independently of confounding factors such as ischemic heart disease and baseline LVEF and left ventricular dimension. CONCLUSIONS: Our findings suggest that heart rate reduction in the early phase after heart failure onset is a powerful independent predictor of the subsequent recovery of LVEF in HFrEF patients.

Pharmacological Investigation of Hypoalbuminemia on the Prolonged and Potentiated Action of Midazolam in Rats.

Midazolam (MDZ) is clinically used for its sedative and anticonvulsant properties. However, its prolonged or potentiated effects are sometimes concerning. The main binding protein of MDZ is albumin, and reduced serum albumin levels could lead to MDZ accumulation, thereby potentiating or prolonging its effects. Previous investigations have not thoroughly examined these phenomena from a behavioral pharmacology standpoint. Consequently, this study aimed to evaluate both the prolonged and potentiated effects of MDZ, as well as the effects of serum albumin levels on the action of MDZ in low-albumin rats. Male Wistar rats were classified into control (20% protein diet), low-protein (5% protein), and non-protein groups (0% protein diet) and were fed the protein-controlled diets for 30 d to obtain low-albumin rats. The locomotor activity and muscle relaxant effects of MDZ were evaluated using the rotarod, grip strength, and open-field tests conducted 10, 60, and 120 min after MDZ administration. Serum albumin levels decreased significantly in the low-protein and non-protein diet groups compared with those in the control group. Compared with the control rats, low-albumin rats demonstrated a significantly shorter time to fall, decreased muscle strength, and a significant decrease in the distance traveled after MDZ administration in the rotarod, grip strength, and open-field tests, respectively. Decreased serum albumin levels potentiated and prolonged the effects of MDZ. Hence, serum albumin level is a critical parameter associated with MDZ administration, which should be monitored, and any side effects related to decreased albumin levels should be investigated.

The E/e' ratio on echocardiography as an independent predictor of the improvement of left ventricular contraction in patients with heart failure with reduced ejection fraction.

OBJECTIVE: Clinical feature of heart failure with improved ejection fraction (HFimpEF) remains to be fully elucidated. The present study investigated the association of clinical and echocardiographic parameters with the subsequent improvement of left ventricular ejection fraction (LVEF) in heart failure with reduced ejection fraction (HFrEF). METHODS: From outpatients with a history of hospitalized for heart failure, 128 subjects diagnosed as HFrEF (LVEF <40%) on heart failure hospitalization were enrolled and longitudinally surveyed. During follow-up periods more than 1 year, 58 and 42 patients were identified as HFimpEF (improved LVEF to ≥40% and its increase of ≥10 points) and persistent HFrEF, respectively. RESULTS: There was no difference in age or sex between the two groups with HFimpEF and persistent HFrEF. The rate of ischemic heart disease was lower and that of tachyarrhythmia was higher in the HFimpEF group than in the persistent HFrEF group. At baseline (i.e., on heart failure hospitalization), LVEF did not differ between the two groups, but left ventricular systolic and diastolic diameters were already smaller and the ratio of early diastolic transmitral velocity to early diastolic tissue velocity (E/e') was lower in the HFimpEF group. A multiple logistic regression analysis revealed that lower baseline E/e' was a significant determinant of HFimpEF, independently of confounding factors such as ischemic heart disease, tachyarrhythmia, and baseline left ventricular dimension. CONCLUSION: Our findings indicate that the lower ratio of E/e' in the acute phase of heart failure onset is an independent predictor of the subsequent improvement of LVEF in HFrEF patients.

Renoprotective effect of chronic treatment with sodium-glucose cotransporter 2 inhibitors and its associated factors in Japanese patients with chronic heart failure and diabetes.

Background: Recent clinical trials have shown that sodium-glucose cotransporter 2 (SGLT2) inhibitors have beneficial effects on renal function in heart failure patients. This study confirmed the renoprotective effect of treatment with SGLT2 inhibitors in Japanese patients with chronic heart failure and diabetes and further investigated what cardiac/hemodynamic and noncardiac factors are involved in its effect. Methods: Eligible 50 outpatients with chronic heart failure and type-2 diabetes mellitus chronically taking SGLT2 inhibitors were enrolled. Annual changing rates of estimated glomerular filtration rate (eGFR) were compered before and after treatment with SGLT2 inhibitors and the associations of the change in eGFR slope after SGLT2 inhibitor administration with changes in various clinical and echocardiographic parameters were evaluated. Results: The mean follow-up periods before and after SGLT2 inhibitor administration were 2.6 and 1.9 years, respectively. Changing rates of eGFR per year were significantly improved after treatment with SGLT2 inhibitors (-5.78 ± 7.67 to -0.43 ± 10.81 mL/min/1.73 m2/year, p = 0.006). The daily doses of loop diuretics were not altered after SGLT2 inhibitor administration. Neither decreased body weight nor increased hematocrit was associated with the change in eGFR slope before and after SGLT2 inhibitor administration. While, the decrease in inferior vena cava diameter and the increase in its respiratory collapsibility were significantly correlated with the improvement of eGFR decline slope after SGLT2 inhibitor administration. Conclusions: Our findings indicated that chronic treatment with SGLT2 inhibitors ameliorated annual decline in eGFR in Japanese patients with chronic heart failure, suggesting the possibility that the improvement of venous congestion was involved in its renoprotective effect.

Achilles tendon thickness is associated with coronary lesion severity in acute coronary syndrome patients without familial hypercholesterolemia.

BACKGROUND: Thickening of Achilles tendon (≥9 mm on radiography) is one of the diagnostic criteria for familial hypercholesterolemia (FH). Since FH is associated with premature coronary artery disease (CAD) including acute coronary syndrome (ACS), measurement of Achilles tendon thickness (ATT) is important for early diagnosis of FH. However, clinical significance of mild thickening of Achilles tendon in non-FH patients with CAD is unclear. The present study investigated the association of ATT with coronary lesion severity in early-onset ACS without clinically diagnosed FH. METHODS: From outpatients who had a history of ACS under 60 years old, 76 clinically non-FH subjects (71 men and 5 women; mean age at the onset of ACS, 50.5 years) with maximum ATT of <9 mm were enrolled in this study. The severity of coronary lesions was assessed by SYNTAX score derived from coronary angiography at the onset of ACS. RESULTS: ATT levels were not significantly different among patients with ST-elevation myocardial infarction (STEMI, n=47), non-STEMI (n=12), and unstable angina (n=17). Whereas, both average and maximum ATT were significantly larger in patients with multivessel lesions (n=25) than in those with single-vessel disease (n=51). Furthermore, SYNTAX score was positively correlated with average ATT (r=0.368, p=0.0011) and maximum ATT (r=0.388, p=0.0005). As for the relation to clinical parameters, maximum ATT had positive correlations with body mass index and C-reactive protein. A multiple regression analysis revealed that average and maximum ATT were significantly associated with SYNTAX score, independently of various confounding factors. CONCLUSIONS: Our findings demonstrated that ATT, even though its level was <9 mm, was associated with coronary lesion severity in clinically non-FH patients with early-onset ACS. Apart from diagnosing FH, ATT may be a predictor of the progression of CAD.

Long-term administration of tolvaptan ameliorates annual decline in estimated glomerular filtration rate in outpatients with chronic heart failure.

Protective effects of tolvaptan against worsening renal function in acute heart failure have been shown. However, long-term effects of its agent on renal function remain to be elucidated. The present study investigated retrospectively whether long-term treatment with tolvaptan exerts renoprotective effects in patients with chronic heart failure, by comparing serial changes in estimated glomerular filtration rate (eGFR) for years before and after tolvaptan administration. From 63 outpatients with chronic heart failure taking diuretics including tolvaptan, 34 patients whose eGFR levels were continuously measured for more than 6 months both before and after administration of tolvaptan (average dose, 7.8 mg/day at the end of the follow-up period) were selected as eligible for the present analyses. All eGFR values were separately plotted before and after the initiation of treatment with tolvaptan (except hospitalization periods) along the time course axis and the slope of the linear regression curve was calculated as an annual change in eGFR. The mean follow-up periods before and after tolvaptan administration were 1197 and 784 days (3.3 and 2.1 years), respectively. Changing rates of eGFR per year were significantly ameliorated after treatment with tolvaptan (mean ± SD, - 8.02 ± 9.35 to - 1.62 ± 5.09 mL/min/1.73m2 /year, P = 0.001). In echocardiographic parameters, inferior vena cava (IVC) diameter significantly decreased after tolvaptan administration, and the decrease in IVC diameter was correlated with the improvement of eGFR decline slope after administration of tolvaptan (P = 0.0075). This longitudinal observational study indicated that long-term treatment with tolvaptan ameliorated annual decline in eGFR in outpatients with chronic heart failure. Our findings suggest that tolvaptan has a protective effect against chronically worsening renal function in heart failure patients.

Inappropriate direct oral anticoagulant dosing in atrial fibrillation patients is associated with prescriptions for outpatients rather than inpatients: a single-center retrospective cohort study.

BACKGROUND: Inappropriate dosing of direct oral anticoagulants (DOACs) has been associated with clinical safety and efficacy; however, little is known about clinical data associated with an inappropriate DOAC dosing in Japan. In addition, there is no report in which the appropriateness of DOAC dosing between prescription for inpatients and for outpatients was examined. In this study, we aimed to investigate the prevalence and factors associated in the inappropriate dosing of DOACs in patients with atrial fibrillation (AF). METHODS: The retrospective cohort study was conducted at a single Japanese university hospital. Both inpatients and outpatients, who were diagnosed with AF and for whom treatment with either dabigatran, rivaroxaban, apixaban, or edoxaban was initiated between April 1, 2014 and March 31, 2018, were enrolled in the study. Appropriateness of DOAC dosing was assessed according to the manufacturer's labeling recommendations (dose reduction criteria) of each DOAC. Inappropriate reduced dose, namely, underdosing, was defined as prescription of a reduced dose of DOAC despite the patient not meeting the dose reduction criteria. Inappropriate standard dose, namely, overdosing, was defined as prescription of a standard dose of DOAC despite the patient meeting the dose reduction criteria. Inappropriate DOAC dosing was defined as a deviation of the recommended dose (both underdosing and overdosing). RESULTS: A total of 316 patients (dabigatran, 28; rivaroxaban, 107; apixaban, 116; and edoxaban, 65) were included, with a median (interquartile range) age of 75 (66-81) years and 62.3% male. DOACs were prescribed at an appropriate standard dose in 39.2% of patients, an appropriate reduced dose in 36.7%, an inappropriate standard dose in 2.5%, and an inappropriate reduced dose in 19.3%. Multivariate analysis revealed that the inappropriate dosing of DOACs was significantly associated with prescriptions for outpatients (vs. inpatients; odds ratio [OR] 2.87, 95% confidence interval [CI] 1.53-5.62, p < 0.001) and those with higher HAS-BLED scores (OR 1.87, 95% CI 1.42-2.51, p < 0.001). CONCLUSIONS: Our results demonstrated that the inappropriate dosing of DOACs occurred in approximately 20% of AF patients, and was more frequent in outpatients (vs. inpatients) and in those with a higher risk of bleeding. It is recommended that pharmacists play a greater role in assisting in the prescription process to help physicians make better decisions.

Association between medication adherence and illness perceptions in atrial fibrillation patients treated with direct oral anticoagulants: An observational cross-sectional pilot study.

OBJECTIVE: The aim of this study was to examine the association between medication adherence and illness perceptions, and to explore the factors associated with poor medication adherence in atrial fibrillation (AF) patients receiving direct oral anticoagulants (DOACs) in a real-world clinical setting. METHODS: An observational cross-sectional pilot study was conducted at a single Japanese university hospital. One hundred and twenty-nine patients who were diagnosed with AF and who were taking DOACs were recruited from outpatients between January 4th and April 25th, 2017. We evaluated medication adherence to DOACs using the Morisky Medication Adherence Scale-8 (MMAS-8) and illness perceptions using the Brief Illness Perception Questionnaire (BIPQ). The patients' characteristics and clinical data were collected from electronic medical records. RESULTS: Ninety-nine (76.7%) patients (male, n = 74; mean age, 71.4±9.8 years) participated in this study. According to the MMAS-8, 21 (21.2%) of the patients were classified into the poor adherence group (MMAS-8 score of <6), and 78 (78.8%) were classified into the good adherence group (MMAS-8 score of 6-8). A multivariate logistic regression analysis revealed that age (per year, odds ratio [OR] 0.912, 95% confidence interval [CI] 0.853-0.965, p = 0.001), a history of warfarin use (OR 0.181, 95% CI 0.033-0.764, p = 0.019), duration of DOAC exposure (per 100 days, OR 1.245, 95% CI 1.084-1.460, p = 0.001), and the BIPQ emotional response score (per 1 point, OR 1.235, 95% CI 1.015-1.527, p = 0.035) were significantly associated with poor medication adherence in AF patients receiving DOACs. CONCLUSION: Poor medication adherence to DOACs was strongly associated with a stronger emotional response (i.e. stronger feelings of anger, anxiety, and depression), as well as younger age, the absence of a history of warfarin treatment, and longer DOAC exposure. Further evaluation of the factors associated with medication adherence in AF patients and the development and execution of strategies for improving poor adherence are warranted in the real-world clinical setting.

Vancomycin induces reactive oxygen species-dependent apoptosis via mitochondrial cardiolipin peroxidation in renal tubular epithelial cells.

Vancomycin (VCM) is a first-line antibiotic for serious infections caused by methicillin-resistant Staphylococcus aureus. However, nephrotoxicity is one of the most complaint in VCM therapy. We previously reported that VCM induced apoptosis in a porcine proximal tubular epithelial cell line (LLC-PK1), in which mitochondrial complex I may generate superoxide, leading to cell death. In the present study, VCM caused production of mitochondrial reactive oxygen species and peroxidation of the mitochondrial phospholipid cardiolipin that was reversed by administration of the mitochondrial uncoupler carbonyl cyanide-4-(trifluoromethoxy) phenylhydrazone (FCCP). FCCP also significantly suppressed VCM-induced depolarization of the mitochondrial membrane and apoptosis. Moreover, the lipophilic antioxidant vitamin E and a mitochondria-targeted antioxidant, mitoTEMPO, also significantly suppressed VCM-induced depolarization of mitochondrial membrane and apoptosis, whereas vitamin C, n-acetyl cysteine, or glutathione did not provide significant protection. These findings suggest that peroxidation of the mitochondrial membrane cardiolipin mediated the VCM-induced production of intracellular reactive oxygen species and initiation of apoptosis in LLC-PK1 cells. Furthermore, regulation of mitochondrial function using a mitochondria-targeted antioxidant, such as mitoTEMPO, may constitute a potential strategy for mitigation of VCM-induced proximal tubular epithelial cell injury.

Filament perforation model for mouse subarachnoid hemorrhage: surgical-technical considerations.

OBJECTIVE: Mouse subarachnoid hemorrhage (SAH) models are becoming increasingly important. We aimed to report and discuss the detailed technical-surgical approach and difficulties associated with the circle of Willis perforation (cWp) model, with reference to the existing literature. METHODS: First, the cWp model was reproduced using ddY mice following scarification at 0 h, Days 1, 2, and 3 after SAH. Second, C57BL/6 mice were subjected to SAH with histological examination on Days 1, 2, and 3. Sham-operated mice were sacrificed on Day 2. Neurological performance, amount of subarachnoid blood, cerebral vasospasm (CVS), and neuronal injury were assessed. Relevant articles found in the MEDLINE database were reviewed. RESULTS: Induction of SAH was successfully reproduced. The volume of subarachnoid blood decreased with time due to resorption. Neurological performance was worse in SAH compared with sham. Signs of CVS could be confirmed on Days 2 and 3, but not Day 1. The cumulative number of microthrombi was significantly higher on Days 2 and 3, but not Day 1. Apoptotic and degenerative neurons were found in the cortex and hippocampal area. Our review of the literature revealed the cWp model to be the most frequently used. The present findings largely confirmed previously published results. However, detailed technical-surgical description and its discussion were sparse, which we provide here. CONCLUSIONS: The current study provides additional useful information characterizing the cWp model. This model may be of first choice at present, as important pathologies can be reproduced and most findings in the literature are based on it.

Mitochondrial superoxide production contributes to vancomycin-induced renal tubular cell apoptosis.

Vancomycin chloride (VCM), a glycopeptide antibiotic, is widely used for the therapy of infections caused by methicillin-resistant Staphylococcus aureus. However, nephrotoxicity is a major adverse effect in VCM therapy. In this study, we investigated the cellular mechanisms underlying VCM-induced renal tubular cell injury in cultured LLC-PK1 cells. VCM induced a concentration- and time-dependent cell injury in LLC-PK1 cells. VCM caused increases in the numbers of annexin V-positive/PI-negative cells and TUNEL-positive cells, indicating the involvement of apoptotic cell death in VCM-induced renal cell injury. The VCM-induced apoptosis was accompanied by the activation of caspase-9 and caspase-3/7 and reversed by inhibitors of these caspases. Moreover, VCM caused an increase in intracellular reactive oxygen species production and mitochondrial membrane depolarization, which were reversed by vitamin E. In addition, mitochondrial complex I activity was inhibited by VCM as well as by the complex I inhibitor rotenone, and rotenone mimicked the VCM-induced LLC-PK1 cell injury. These findings suggest that VCM causes apoptotic cell death in LLC-PK1 cells by enhancing mitochondrial superoxide production leading to mitochondrial membrane depolarization followed by the caspase activities. Moreover, mitochondrial complex I may play an important role in superoxide production and renal tubular cell apoptosis induced by VCM.

ADAMTS13 gene deletion enhances plasma high-mobility group box1 elevation and neuroinflammation in brain ischemia-reperfusion injury.

Highly adhesive glycoprotein von Willebrand factor (VWF) multimer induces platelet aggregation and leukocyte tethering or extravasation on the injured vascular wall, contributing to microvascular plugging and inflammation in brain ischemia-reperfusion. A disintegrin and metalloproteinase with thrombospondin type-1 motifs 13 (ADAMTS13) cleaves the VWF multimer strand and reduces its prothrombotic and proinflammatory functions. Although ADAMTS13 deficiency is known to amplify post-ischemic cerebral hypoperfusion, there is no report available on the effect of ADAMTS13 on inflammation after brain ischemia. We investigated if ADAMTS13 deficiency intensifies the increase of extracellular HMGB1, a hallmark of post-stroke inflammation, and exacerbates brain injury after ischemia-reperfusion. ADAMTS13 gene knockout (KO) and wild-type (WT) mice were subjected to 30-min middle cerebral artery occlusion (MCAO) and 23.5-h reperfusion under continuous monitoring of regional cerebral blood flow (rCBF). The infarct volume, plasma high-mobility group box1 (HMGB1) level, and immunoreactivity of the ischemic cerebral cortical tissue (double immunofluorescent labeling) against HMGB1/NeuN (neuron-specific nuclear protein) or HMGB1/MPO (myeloperoxidase) were estimated 24 h after MCAO. ADAMTS13KO mice had larger brain infarcts compared with WT 24 h after MCAO (p < 0.05). The rCBF during reperfusion decreased more in ADAMTS13KO mice. The plasma HMGB1 increased more in ADAMTS13KO mice than in WT after ischemia-reperfusion (p < 0.05). Brain ischemia induced more prominent activation of inflammatory cells co-expressing HMGB1 and MPO and more marked neuronal death in the cortical ischemic penumbra of ADAMTS13KO mice. ADAMTS13 deficiency may enhance systemic and brain inflammation associated with HMGB1 neurotoxicity, and aggravate brain damage in mice after brief focal ischemia. We hypothesize that ADAMTS13 protects brain from ischemia-reperfusion injury by regulating VWF-dependent inflammation as well as microvascular plugging.

Reducing acyl migration during purification of 2-arachidonoylglycerol from biological samples before gas chromatography mass spectrometry analysis.

Endocannabinoid 2-arachidonoylglycerol (2-AG) regulates several important physiological processes in the brain. 2-AG is commonly quantified by gas chromatography mass spectrometry after an initial purification step. The most precise and rapid purification utilizes C(18) solid-phase extraction, but quantification problems can arise with acyl migration from 2-AG to 1-arachidonoylglycerol. We found that extraction with methanol promoted this migration, but acetone and diethyl ether (Et(2)O) did not. Acetone and Et(2)O were used to develop a purification method for the direct determination of 2-AG.

Sex differences in the benefits of rehabilitative training during adolescence following neonatal hypoxia-ischemia in rats.

Much effort and many resources are being devoted to rehabilitative programs for children with disabilities caused by neonatal hypoxic-ischemic encephalopathy without clear evidence of the efficacy of such programs. We recently reported that rehabilitative training tasks during adolescence improve spatial learning impairment following neonatal hypoxic-ischemic injury in rats without histological improvement. In the present study we focused on sex differences. Wister rat pups were exposed to a unilateral hypoxic-ischemic insult at 7 days of age. Six weeks after hypoxia-ischemia, rehabilitative training tasks were started. The tasks consisted of the plus maze, the eight-arm radial maze, and the choice reaction time task. Sixteen weeks after the insult, the water maze task was performed to evaluate spatial learning ability. Afterwards, we morphologically examined brain injury. Our rehabilitative training significantly improved swimming time and length in females (P<0.01) but not in males. Likewise, the training ameliorated infarct areas in the injured cerebral hemisphere in females but not in males (P<0.01). These results suggest that it may be important to develop and evaluate cognitive rehabilitation programs for children with brain injury on the basis of gender.

Supervised adaptive downsampling for P300-based brain computer interface.

To realize Brain Computer Interface, a recording electroencephalogram (EEG) and determining whether or not P300 is evoked by the presented stimulus have become increasingly important. Using the machine learning method for this classification is effective, but constructing feature vectors with all data points might result in very high-dimensional data. Because such redundant features are undesirable from the viewpoint of computation and classification performance, EEG has been downsampled in several studies. In the present study, we propose a new downsampling method aiming at the improvement of P300 classification accuracy. In particular, each single trial EEG is segmented at non-uniform intervals and then averaged in each segment. The segmentation is decided in such a way that the degree of separating two classes from training data is increased by applying a time series segmentation algorithm. Our experiment using the BCI Competition III P300 Speller paradigm data set demonstrated that our method resulted in higher accuracy than traditional downsampling methods.