Disease management using home-based cardiac rehabilitation for patients with heart failure.

Home-based cardiac rehabilitation (HBCR) is expected to address the low participation rate in cardiac rehabilitation; however, it is not covered by insurance in Japan, and the optimal method for monitoring a patient's condition during exercise has not been determined. Patients hospitalized for heart failure often deteriorate soon after discharge and require appropriate disease monitoring. In this report, we describe cases in which real-time monitoring of exercise intensity, electrocardiography, and video chat during HBCR was useful in the management of heart failure. Furthermore, the use of HBCR enabled frequent disease monitoring, even during the coronavirus disease 2019 pandemic, and timely medicine adjustment. Learning objective: Clinicians cannot perform radiography, blood tests, or physical examinations at home during home-based cardiac rehabilitation (HBCR). Therefore, it is particularly important to reconsider the appropriate monitoring indicators for HBCR and apply them to disease management. Our cases suggest that real-time monitoring of the following three indicators is useful for disease management using HBCR: (1) exercise intensity, (2) electrocardiography, and (3) shortness of breath.

Effect of Exercise Training in Heart Failure Patients Without Echocardiographic Response to Cardiac Resynchronization Therapy.

Background: Cardiac resynchronization therapy (CRT) is an effective treatment of heart failure (HF) with ventricular dyssynchrony, but not all patients respond to a similar extent. We investigated the efficacy and safety of exercise training (ET) in patients without response to CRT. Methods and Results: Thirty-four patients who participated in a 3-month ET program and underwent cardiopulmonary exercise testing at baseline and after the program were divided into 17 responders and 17 non-responders based on echocardiographic response criteria: either an increase in ejection fraction (EF) ≥10% or a reduction in left ventricular (LV) end-systolic volume ≥10%. Baseline characteristics including peak oxygen uptake (V̇O2) and isometric knee extensor muscle strength (IKEMS) were similar in both groups, but non-responders had lower EF and larger LV. During the ET program, neither group had exercise-related adverse event including life-threatening ventricular arrhythmia. Peak V̇O2 and IKEMS were significantly improved in both groups and there was no significant difference in change in peak V̇O2 or IKEMS between responders and non-responders. On multiple regression analysis, change in IKEMS was an independent predictor of change in peak V̇O2, whereas the response to CRT was not. Conclusions: In HF patients undergoing CRT implantation, ET safely improved exercise capacity regardless of response to CRT, suggesting that even advanced HF patients without response to CRT can possibly benefit from ET.

Predictors of improvements in exercise capacity during cardiac rehabilitation in the recovery phase after coronary artery bypass graft surgery versus acute myocardial infarction.

This study aimed to elucidate the predictors of improvements in exercise capacity during cardiac rehabilitation (CR) in the recovery phase after coronary artery bypass graft surgery (CABG) versus acute myocardial infarction (AMI). We studied 152 patients (91 after AMI and 61 after CABG) who participated in a 3-month CR program. All patients underwent a cardiopulmonary exercise test, blood tests, maximal quadriceps isometric strength (QIS) measurement, and bioelectrical impedance body composition measurement at the beginning and end of the 3-month CR program. At baseline, the percentage of predicted peak oxygen uptake (%pred-PVO2), maximal QIS, and hemoglobin (Hb) were significantly lower, while C-reactive protein (CRP) was significantly higher, in the CABG than the AMI group. After the 3-month CR, %change in PVO2 (%ΔPVO2) was significantly greater in the CABG than the AMI group (18 ± 15% vs 11 ± 12%, P < 0.01). At univariate analysis, baseline plasma brain natriuretic peptide (BNP), %change in maximal QIS after CR (%Δ maximal QIS), and change in plasma hemoglobin (ΔHb) significantly correlated with %ΔPVO2 in the CABG group, whereas only baseline %pred-PVO2 did so in the AMI group. Multiple regression analysis revealed that the same factors were independent and significant predictors of %ΔPVO2 in the CABG and AMI groups. The predictors of improvements in exercise capacity after CR differed between patients after CABG or AMI. Specifically, in CABG patients both enhancing QIS and correcting anemia may contribute to greater improvements in exercise capacity after CR, while a more effective CR program should be designed for CABG patients with high baseline BNP.

Cholinesterase levels predict exercise capacity in cardiac recipients early after transplantation.

PURPOSE: Although cardiac rehabilitation is recommended for patients early after heart transplantation (HTx), adequate exercise effect cannot always be obtained, partly because in patients with chronic heart failure, exercise capacity is reduced due to malnutrition while waiting for HTx. This study aimed to investigate the relationships between exercise capacity and clinical variables, including nutritional indicators, early after HTx. PATIENTS AND METHODS: Forty-three HTx recipients were studied. The mean age at HTx was 38 ± 14 years, and 86% were male. We assessed the relationships between peak oxygen uptake (VO2 ) and clinical variables, including plasma B-type natriuretic peptide (BNP), isometric knee extensor muscle strength (KEMS), and nutritional indicators within 1 week of their respective discharges. RESULTS: Peak VO2 correlated positively with isometric KEMS (r = .63, P < .0001) and negatively with BNP level (r = -.37, P = .015). Of the nutritional indicators, only cholinesterase levels had a significant relationship with peak VO2 (r = .34, P = .028), whereas the Geriatric Nutritional Risk Index and the Controlling Nutritional Status scores did not. In multiple linear regression analysis, cholinesterase levels and isometric KEMS were independent predictors of peak VO2 . CONCLUSION: Cholinesterase levels predicted exercise capacity early after HTx.

An automatic system using mobile-agent software to model the calculation process of a chemical vapor deposition film deposition simulator.

We have developed an automatic modeling system for calculation processes of the simulator to reproduce experimental results of chemical vapor deposition (CVD), in order to decrease the calculation cost of the simulator. Replacing the simulator by the mathematical models proposed by the system will contribute towards decreasing the calculation costs for predicting the experimental results. The system consists of a mobile agent and two software resources in computer networks, that is, generalized modeling software and a simulator reproducing cross-sections of the deposited films on the substrates with the micrometer- or nanometer-sized trenches. The mobile agent autonomously creates appropriate models by moving to and then operating the software resources. The models are calculated by partial least squares regression (PLS), quadratic PLS (QPLS) and error back propagation (BP) methods using artificial neural networks (ANN) and expresses by mathematical formulas to reproduce the calculated results of the simulator. The models show good reproducibility and predictability both for uniformity and filling properties of the films calculated by the simulator. The models using the BP method yield the best performance. The filling property data are more suitable to modeling than film uniformity.

Comparative hemodynamic effects of hypotension induced by diadenosine tetraphosphate (AP4A) and ATP in dogs.

ATP and diadenosine tetraphosphate (AP4A) have been shown to produce vasodilation mediated by P1- and P2-purinoceptor, respectively. The differing mechanisms involved in this vasodilating activity may induce different systemic hemodynamic changes. We compared the hemodynamic effects of AP4A-induced hypotension with those induced by ATP. Fourteen mongrel dogs were anesthetized with 0.87% halothane in oxygen (1 MAC). After the baseline period, mean arterial pressure was reduced to 60 mmHg for 60 min by the infusion of AP4A or ATP. The ATP- and AP4A-induced hypotension resulted in a maximum reduction in systemic vascular resistance of 43% and 46%, respectively (P<0.01), associated with a significant increase in stroke volume index. With ATP, a 20% of maximum increase (P<0.05) in cardiac index (CI) was observed during the induced hypotension. In contrast, AP4A-induced hypotension did not result in any changes in CI throughout the observation period. The varying results concerning CI during the ATP- and AP4A-induced hypotension were probably due to differences in ventricular filling pressure, since AP4A-induced hypotension was associated with decreases (P<0.01) in both right atrial and pulmonary capillary wedge pressures, whereas neither of these variables significantly changed with ATP. The hypotension induced by either ATP or AP4A was associated with a significant decrease in heart rate (HR). However, both the magnitude and duration of decreases in HR due to ATP-induced hypotension were more pronounced than those seen with AP4A. In conclusion, while both drugs were equally capable of inducing hypotension, our results suggest that AP4A was more suitable for induced hypotension because of its potent vasodilatory action with venodilation and less negative chronotropic action.