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Peak oxygen uptake (VO 2 ), evaluated as exercise tolerance, is a strong predictor of life prognosis regardless of health condition. Several previous studies have reported that peak VO 2 is higher in those with a greater decrease in muscle oxygen saturation (SmO 2 ) in the active muscles during incremental exercise. However, the skeletal muscle characteristics of individuals exhibiting a greater decrease in SmO 2 during active muscle engagement in incremental exercise remain unclear. This study aimed to clarify the relationship among muscle strength, muscle endurance, and skeletal muscle oxygenation dynamics in active leg muscles during incremental exercise. Twenty-four healthy young men were included and categorized into the non-moderate-to-high muscular strength and endurance group (those with low leg muscle strength, endurance, or both; n = 11) and the moderate-to-high muscular strength and endurance group (those with both moderate-to-high leg muscle strength and endurance; n = 13). All participants underwent cardiopulmonary exercise testing combined with near-infrared spectroscopy to assess whole-body peak VO 2 and the change in SmO 2 at the lateral vastus lateralis from rest to each exercise stage as skeletal muscle oxygenation dynamics. A linear mixed-effects model, with the change in SmO 2 from rest to each stage as the dependent variable, individual participants as random effects, and group and exercise load as fixed effects, revealed significant main effects for both group (P = 0.001) and exercise load (P < 0.001) as well as a significant interaction between the two factors (P < 0.001). Furthermore, multiple-comparison test results showed that the change in SmO 2 from rest to 40%-100% peak VO 2 was significantly higher in the moderate-to-high muscular strength and endurance group than in the non-moderate-to-high muscular strength and endurance group. Maintaining both muscle strength and endurance at moderate or higher levels contributes to high skeletal muscle oxygenation dynamics (i.e., greater decrease in SmO 2 ) during moderate- or high-intensity exercise., (© 2024. The Author(s).)

It has been reported that a single-dose cardioplegia interval is useful, but the safe interval doses are not clear. We aimed to investigate the impact of the cardioplegia interval on myocardial protection using the modified St. Thomas solution. We included consecutive isolated minimally invasive mitral valvuloplasty procedures ( n = 229) performed at a hospital and medical center from January 2014 to December 2020. We compared postoperative peak creatine kinase MB and creatine kinase levels and other indicators between the short (Group S, n = 135; maximum myocardial protection interval <60 minutes) and long (Group L, n = 94; maximum myocardial protection interval ≥60 minutes) interval groups. Propensity score matching was used to adjust for confounders between the two groups. After propensity score matching, Groups S and L contained 47 patients each. Groups S and L did not differ significantly in peak creatine kinase MB (45.8 ± 26.3 IU/L and 41.5 ± 27.9 IU/L, respectively; p = .441) and creatine kinase levels (1,133 ± 567 IU/L and 1,100 ± 916 IU/L, respectively; p = .837) after admission to the intensive care unit on the day of surgery based on propensity score matching. In multivariate analysis, a cardioplegia dosing interval ≥60 minutes was not significantly associated with the maximum creatine kinase MB level after admission to the intensive care unit on the day of surgery ( p = .354; 95% confidence interval: -1.67 to 4.65). Using the antegrade modified St. Thomas solution, the long interval dose method is useful and safe in minimally invasive mitral valvuloplasty., (© Copyright 2022 AMSECT.)

Objective: Preoperative performance status is an important factor in thoracic surgery, but little is known about the effect of preoperative physical activity (PA) on the postoperative course. This study investigated the associations between preoperative PA and postoperative complications and clinical outcomes of lung cancer surgery., Methods: This prospective observational study included patients who underwent surgery for lung cancer at a single institution. PA was measured before hospitalization for 5 consecutive days and then after surgery until hospital discharge. The daily step count and time spent performing moderate intensity activity (> 3 metabolic equivalents) were measured with an accelerometer. We examined the correlations between PA and preoperative pulmonary function and physical fitness, and examined the relationship between postoperative complication and PA. Finally, a multivariate analysis was performed with pre-hospital PA as the dependent variable., Results: Forty-two patients were analyzed. Univariate analysis found no correlation between pre-hospital PA and preoperative pulmonary function, but found significant positive correlations between pre-hospital PA and time spent performing moderate intensity activity, in-hospital PA, preoperative 6-minute walk distance, and maximum gait speed (r > 0.5, p < 0.01). The nine patients who developed postoperative complications had significantly lower pre-hospital and postoperative step count than the patients with no complication (p = 0.04). Multiple regression analysis showed that pre-hospital PA was significantly associated with time spent performing moderate intensity activity, maximum gait speed, and postoperative complication., Conclusions: Evaluation of pre-hospital PA is useful in predicting the postoperative course after lung cancer surgery., Competing Interests: The authors have no conflicts of interest to declare., (2021, JAPANESE PHYSICAL THERAPY ASSOCIATION.)

Objectives: In the field of exercise physiology, there has been great interest in exploring circulating microRNAs (miRs) as potential biomarkers. However, it remains to be determined whether circulating miRs reflect cardiorespiratory fitness. The aim of this study was to investigate the association between circulating levels of specific miRs and cardiorespiratory fitness evaluated by cardiopulmonary exercise testing (CPET) after acute myocardial infarction (MI)., Methods: Twenty patients who had had an acute MI were included. All patients underwent CPET in the convalescent phase. Quantitative real-time polymerase chain reaction analyses for miR-181 members (a/b/c) and miR-484 were performed to determine the expression levels in the peripheral blood of the included patients and healthy control subjects (n=5)., Results: Post-MI patients showed impaired exercise tolerance and ventilatory efficiency in CPET analysis. Compared with controls, circulating levels of miR-181a and 181c were gradually and significantly elevated through the 1st to 7th days after acute MI, whereas miR-181b and miR-484 were not. Circulating miR levels did not correlate with clinical or echocardiographic parameters. However, circulating levels of miR-181c and miR-484 on the 7th day showed significant positive correlations with the anaerobic threshold and peak oxygen consumption from CPET analysis. Moreover, miR-181c levels were inversely associated with the ventilatory inefficiency index. Patients with high exercise capacity after MI showed significantly higher expressions of circulating miR-181c and miR-484 than those with low exercise capacity., Conclusions: The results of this pilot study suggest that circulating levels of miR-181c and miR-484 after acute MI may be predictive biomarkers of post-MI cardiorespiratory fitness., Competing Interests: CONFLICTS OF INTEREST: The authors have no conflicts of interest to declare., (©2021 The Japanese Association of Rehabilitation Medicine.)

Background: This prospective randomized multicenter open-label trial evaluated whether sodium-glucose cotransporter-2 inhibitor (SGLT2-i) improves left ventricular (LV) pump function and suppresses elevation of LV filling pressure (LVFP) and right ventricular systolic pressure (RVSP) during exercise in type 2 diabetes mellitus (T2DM) patients., Methods and results: Based on HbA1c and LV ejection fraction, 78 patients with poorly controlled T2DM were randomly assigned to D-group (dapagliflozin 5 mg/day add-on) or C-group (conventional therapy add-on). Physical examination, home and office blood pressure examination, blood tests, and echocardiography at rest and during ergometer exercise were performed at baseline and at 1.5 and 6 months after treatment. The primary endpoint was defined as the change in RVSP (mmHg) between baseline and 6-month follow up. The secondary endpoints were changes in LVFP (ratio), stroke volume index (SVi; mL/m 2 ), and cardiac index (CI; L/min/m 2 ). Both RVSP and LVFP during exercise significantly decreased from baseline to 6 months after starting treatment in the D-group (P<0.001). No changes to either parameter was observed in the C-group. The SVi and CI did not improve in either group. Both home and office blood pressure significantly decreased in the D-group. Decreases in HbA1c were somewhat greater in the C-group., Conclusions: Dapagliflozin significantly improved RVSP and LVFP during exercise in patients with T2DM and cardiovascular risk, which may contribute to favorable effects on heart failure.

Sleep disordered breathing (SDB) was more prevalent in adolescent athletes than expected, and several potential warning signs related to autonomic nerve activity appeared in SDB athletes. SDB screening may prevent associated downstream risks in the future. http://ow.ly/GQqK30nGm8r., Competing Interests: Conflict of interest: Y. Iso has nothing to disclose. Conflict of interest: H. Kitai has nothing to disclose. Conflict of interest: E. Kyuno has nothing to disclose. Conflict of interest: F. Tsunoda has nothing to disclose. Conflict of interest: N. Nishinaka has nothing to disclose. Conflict of interest: M. Funato has nothing to disclose. Conflict of interest: E. Nishimura has nothing to disclose. Conflict of interest: S. Akihiro has nothing to disclose. Conflict of interest: H. Tanuma has nothing to disclose. Conflict of interest: T. Yonechi has nothing to disclose. Conflict of interest: E. Geshi has nothing to disclose. Conflict of interest: T. Sambe has nothing to disclose. Conflict of interest: H. Suzuki has nothing to disclose.

This study was conducted to determine the effects of depression and/or insomnia on masked hypertension (MHT) compared with other types of HT and on variability in home-measured blood pressure (HBP) and clinic BP (CBP). Three hundred and twenty-eight hypertensives (132 women) aged 68±10 years were classified into four BP types: controlled HT (CHT), white-coat HT, MHT and sustained HT (SHT), based on CBP (140/90 mm Hg) and morning HBP (135/85 mm Hg) measurements. A score of ⩾16 on the Center for Epidemiologic Studies Depression Scale (CES-D) was defined as depression. The mean values and s.d. of BP were calculated from measurements taken during the 14 consecutive days just before the CES-D evaluation. Compared with the CHT group, the risk of depression was 2.77-fold higher in the SHT group and even higher in the MHT group (7.02-fold). The association between depression and MHT was augmented in the presence of insomnia and was somewhat stronger in women. A HBP variability index defined as s.d./mean BPs in both morning and night time was significantly higher in MHT than in the other BP types, whereas that of CBP was not. Both morning and night-time HBP variability were significantly higher in depressive patients than in non-depressives. These suggest that depression is associated with MHT and that increases both morning and night-time HBP variability but not CBP variability. Physicians should be mindful of mental stresses such as depression in their hypertensive patients when forming strategies to control BP over the diurnal cycle.

Aim: Among the many factors related to bone marrow cell mobilization, local inflammation induced by cytokines may drive bone marrow cells to the vascular wall, resulting in a thickened neointima. However, the relationship between inflammatory reactions and bone marrow cell invasion has not yet been fully clarified., Methods: We inserted a large wire into the femoral artery in male balb/c(WT), interleukin (IL)-6-knockout (KO) and bone marrow-transplanted (BMT) mice that had received bone marrow cells from KO mice. Immunohistochemistry was performed to evaluate the degree of intimal hyperplasia and inflammation following vascular injury., Results: Three days after the vascular injury, the number of CD34/Sca-1-positive cells in the blood was higher in the KO mice. The numbers of apoptotic cells in the neointima was lower in the KO and BMT mice at two hours after injury. The morphometric analysis performed at one and four weeks after injury showed that the intima/media ratio was significantly lower in the KO and BMT mice, while CD34-positive cells were much more frequent in the WT mice. Furthermore, re-endothelialization appeared earlier in the KO and BMT mice than in the WT mice. No differences in the levels of vascular endothelial growth factor or hepatocyte growth factor were observed in the mice sera between the WT, KO and BMT mice after injury. The in vitro culture of bone marrow cells showed more differentiated smooth muscle-like cells in the WT mice than in the KO mice., Conclusions: IL-6 is involved in neointimal formation following vascular injury, possibly acting through inflammatory effects inducing the production of bone marrow cells.

Background: Nocturnal and early morning hypertension are both significant risk factors for cardiovascular events. It remains unclear whether anxiety disorder affects nocturnal blood pressure (BP), early morning BP, or BP pattern in hypertensive patients., Methods and Results: One hundred and twenty consecutive hypertensive outpatients (77 men and 43 women; mean age, 66±11 years) were divided into 2 groups based on Hospital Anxiety and Depression Scale (HADS) score: a control group (n=78; HADS ≤10) and an anxiety group (42 patients; HADS ≥11). Nocturnal BP, early morning BP, morning BP surge (defined as BP rise ≥50 mmHg), and BP pattern (extreme-dipper/dipper/non-dipper/riser) were measured on ambulatory BP monitoring. Clinical characteristics and BP were also evaluated at physician check-up. There was no significant difference between the 2 groups for BP check-up, but nocturnal and early morning BP were significantly higher in the anxiety group (142±16 mmHg and 152±21 mmHg) than in the control group (126±14 mmHg and 141±18 mmHg). With regard to patients with morning BP surge, nocturnal and early morning BP were also significantly higher in the anxiety group. The relative risk of existing anxiety disorders in riser-type hypertension was 4.48-fold higher (95% confidence interval: 1.58-12.74; P<0.005) than in dipper-type hypertension., Conclusions: Anxiety disorder is associated with nocturnal and early morning hypertension, and may be a risk factor for cardiovascular events.

Background: Angiotensin-converting enzyme inhibitors (ACEI) reduce the mortality in the chronic phase of myocardial infarction (MI), and similar effects of angiotensin receptor blockers (ARB) have been reported. However, these effects of ARB have not yet been established in Japanese patients. A multicenter randomized study was designed for the present study to examine the effect of valsartan as compared to that of ACEI against left ventricular dysfunction after MI., Methods and Results: Patients with acute MI were randomly allocated to either the valsartan group (n=120; mean age 63 +/-1.0) or the ACEI group (n=121; mean age 62.9 +/-1.0) and followed up until 6 months. Left ventriculography was performed during hospital admission and at 6 months. The blood pressure was similar in the 2 groups throughout the study. The incidences of cardiovascular events and target vessel revascularization were similar, although that of adverse events was significantly higher in the ACEI (12.4%) than in the valsartan group (3.3%; P<0.05). There were no differences in left ventricular ejection fraction and left ventricular end-diastolic volume index between the groups., Conclusions: Valsartan exhibits similar efficacy effective to that of ACEI in preventing left ventricular dysfunction in Japanese patients with acute MI, and is, in addition, better tolerated than ACEI.

Background: Granulocyte-colony stimulating factor (G-CSF) affects injured arteries through early endothelialization. Some reports, however, have cautioned that the restenosis rate may increase after G-CSF injection. In the present study, high-dose G-CSF was administered to mice with vascular injury to clarify its effect., Methods and Results: Mice were received daily subcutaneous injections of saline or a high dose (300 microg/kg) of G-CSF for 5 days after vascular injury. In the FACS analysis, CD34-/Sca-1-positive progenitor cells were more abundant in the G-CSF group (p<0.05). Neointimal hyperplasia was more evident in the G-CSF group at 1 week (p<0.05), whereas at 4 weeks it was more evident in the control group (p<0.01). TUNEL-positive cells in the arterial wall were more numerous in the G-CSF group at day 1 (p<0.01). CD34-positive cells were observed in the G-CSF group at 1 week. Re-endothelialization appeared earlier in the G-CSF group (at 4 weeks; p<0.01). An increased number of 1A4-positive smooth muscle cells were found in bone marrow cell culture treated with G-CSF., Conclusion: High-dose G-CSF induced neointimal proliferation through excessive inflammation and bone marrow cell mobilization in the early phase. In the late phase, however, it induced early re-endothelialization and thereby inhibited neointimal hyperplasia.

Aim: Recent evidence suggests that small dense low-density lipoprotein (sd-LDL) particles are more atherogenic than large-LDL in spite of their lower cholesterol content. This study aimed to determine whether sd-LDL-cholesterol (sd-LDL-C) is superior to LDL-C as a biomarker of coronary heart disease (CHD)., Methods: LDL particle size determined by gradient gel electrophoresis and sd-LDL-C concentrations quantified by heparin-magnesium precipitation were compared between 482 stable CHD patients and 389 non-diabetic subjects without CHD who were not receiving any lipid-lowering drugs., Results: Both male and female CHD patients had significantly smaller LDL particles and lower large-LDL-C concentrations (estimated by subtracting the sd-LDL-C concentration from the LDL-C concentration), and significantly higher sd-LDL-C concentrations than the control subjects. LDL-C concentrations were modestly higher and sd-LDL-C concentrations were significantly higher in 258 patients with angiographically documented severe CHD than in the patients with mild CHD irrespective of treatment by LDL-lowering drugs and history of myocardial infarction and/or coronary revascularization. Large-LDL-C concentrations, in contrast, were similar between the two groups. Multivariate logistic regression analysis revealed that sd-LDL-C levels were significantly associated with severe CHD independently of LDL-C., Conclusion: sd-LDL-C levels are more powerful than LDL-C levels for the determination of severe stable CHD.

Objective: Recent studies have suggested that granulocyte colony-stimulating factor (G-CSF) may improve cardiac function after acute myocardial infarction (AMI) by accelerating angiogenesis or cardiomyogenesis, but negative results and side effect of G-CSF have also been reported. However, no previous studies have used large animal models of ischemia/reperfusion to investigate the effect and side effect of G-CSF after AMI., Methods: The diagonal branch of the left anterior descending coronary artery of swine was balloon-occluded for 1 h and then reperfused. The animals of the G-CSF group were injected with G-CSF subcutaneously (5.0 microg/kg/day) for 6 days after MI and then sacrificed after 4 weeks. The control group received the same volume of saline., Results: There were no differences between the groups in the rate of thrombotic obstruction or progression of stenosis lesion in coronary angiography. The ejection fraction and end-diastolic volume in the G-CSF group were not significantly improved over the control values. The fibrotic area was significantly smaller in the G-CSF group than in the controls (P<0.05), and the numbers of vessels counted in anti-von Willebrand factor and anti-alpha-smooth muscle actin-stained sections were significantly larger (P<0.005 and P<0.05, respectively). The expression of collagen III mRNA was significantly lower in the G-CSF group than in the control in the infarct (P<0.0005) and border areas (P<0.005), and TGF-beta mRNA was significantly lower in the G-CSF group in the border area (P<0.05)., Conclusions: G-CSF could modify the healing process after AMI by accelerating angiogenesis in a swine ischemia/reperfusion model. At the dose administered, however, G-CSF did not seem to improve the global cardiac function.