Left Atrial Functional Response after a Marathon

Background: Middle-aged marathon runners have an increased risk of developing atrial fibrillation (AF). A previous study described that repetitive marathon running was associated with left atrial (LA) dysfunction. However, whether this change is common in marathon runners and which runners are at risk of LA dysfunction remain unknown. The purpose of this study was to determine which factors could predict LA dysfunction. Methods and results: We prospectively examined 12 healthy amateur volunteers (9 males, 31±8 years old) who participated in a full marathon. All echocardiographic measurements and speckle-tracking echocardiography were performed before and after the marathon. The endpoint was defined as reduced LA reservoir strain one day after the marathon (non-responder group). Seven participants were in the non-responder group. Age (35±9 vs. 26±2 yrs., p=0.020), augmentation index (76±12 vs. 55±8, p=0.002), and diastolic blood pressures (83±11 vs. 70±7 mmHg, p=0.021) in the non-responder group were significantly higher compared with the responder group. In multivariate linear regression analysis, only the augmentation index was an independent predictor of reduced LA reservoir function after the marathon (β=-0.646, p=0.023). Conclusion: The augmentation index was a predictive marker for reduction in LA reservoir function after a marathon in healthy amateur volunteers

RV Strain in PH due to Left Heart Disease

Background: Recent studies showed that the combined pre- and post-capillary pulmonary hypertension (CpcPH) had worse outcomes compared with isolated post-capillary (Ipc) PH. However, the prognostic factors including right ventricular (RV) function have not been well documented. The aim of this study was to assess the differentiation of PH phenotypes using echocardiography, and the association between RV longitudinal strain and cardiac events. Methods and Results: We prospectively recruited consecutive patients who had undergone right heart catheterization. The primary endpoint was cardiovascular death or readmission due to heart failure. One hundred thirty-seven patients with Group 2 PH were included. A RV longitudinal strain of 17% was sensitive (85%) and specific (70%) to determine the CpcPH. During a median period of 31 months, 43 patients had the primary endpoint during follow-up. In a multivariate analysis, RV longitudinal strain was associated with the primary endpoint in both CpcPH and IpcPH (hazard ratio: HR: 0.84, p =0.003 and HR: 0.86, p =0.001). Conclusions: Lower RV longitudinal strain was independently associated with worse outcomes in CpcPH and IpcPH. RV longitudinal strain may play a prognostic role among PH phenotypes

RV Function in Cardiac Rehabilitation

Cardiac rehabilitation had an important role in the management of heart failure. The predictors of exercise capacity improvement after cardiac rehabilitation are required in the management of heart failure. We demonstrated that patients with higher right ventricular strain during preload augmentation seem to have a benefit more from cardiac rehabilitation. The simple, but novel application of preload stress echocardiography is a noninvasive technique that can be used to find a beneficial group with cardiac rehabilitation.Background: It has been recognized that a comprehensive cardiac rehabilitation (CR) program improves mortality in patients with chronic heart failure (HF). On the other hand, the magnitude of the improvement in exercise capacity after CR differs among individuals. The aim of this study was to assess the echocardiographic determinants of responders to CR using preload stress echocardiography. Methods: We prospectively enrolled 58 chronic HF patients with reduced left ventricular ejection fraction (LVEF) (age 62±11 years; 69% male; LVEF 43±7 %) who had received optimized medical treatment in a CR program for 5 months. We performed preload echocardiographic studies using leg positive pressure (LPP) to assess the echocardiographic parameters during preload augmentation. We defined 41 patients as a development cohort to assess the predictive value of echocardiographic variables. Next, we validated results in the remaining 17 patients as a validation cohort. Results: In the development cohort, significant improvement in peak VO2 (>10%) after CR was observed in 58% patients. In a multivariable logistic regression model, the significant predictor of improvement in exercise capacity was right ventricular (RV) strain during LPP (odds ratio: 3.96 per 1 SD; p =0.01). A RV strain value of –16% during LPP had good sensitivity of 0.79 and specificity of 0.71 to identify patients with improvement in peak VO2. In the validation cohort, an optimal cut off value of RV strain value was the same (AUC: 0.77, sensitivity: 0.78, specificity: 0.65). Conclusion: RV strain during LPP may be an echocardiographic parameter for assessing beneficial effects of CR

更新された左室拡張機能評価勧告と心不全入院患者における心血管イベント

Background: Evaluation of diastolic dysfunction is crucial in determining elevated left atrial pressure. However, a validation of the long-term prognostic value of the newly proposed algorithm updated in 2016 has not been performed. The aim of the present study was to investigate the relative value of the updated 2016 diastolic dysfunction grading system for the incidence of readmission in patients with heart failure (HF) with reduced ejection fraction (HFrEF) and HF with preserved ejection fraction (HFpEF). Methods: Two hundred thirty-two patients hospitalized with HF were retrospectively evaluated. Subjects were divided into two subgroups: those with HFrEF (n = 127) and those with HFpEF (n = 105). Readmission risk scores were calculated using the Yale Center for Outcomes Research and Evaluation HF, LACE index, and HOSPITAL scores. The primary end point was readmission following HF and cardiac death. Results: Over a period of 24 months, 86 patients were either readmitted or died. Multivariate Cox analysis was performed on both the HFrEF and HFpEF groups. In the HFrEF group, both the 2009 and 2016 algorithms had superior incremental value for the association of the primary end point to several readmission risk scores. In the HFpEF group, only the 2016 algorithm led to significant improvement in association with the primary end point. The 2016 algorithm had incremental value over several readmission risk scores alone. Conclusions: The recommendations of the 2016 algorithm can be useful for readmission and cardiac mortality risk assessment in patients with HFrEF and HFpEF. The use of echocardiography to estimate elevated left atrial pressure appears to identify a higher risk group and may allow a more tailored approach to therapy

Detection of the thermal component in GRB 160107A

We present the detection of a blackbody component in gamma-ray burst GRB 160107A emission by using the combined spectral data of the CALET Gamma-ray Burst Monitor (CGBM) and the MAXI Gas Slit Camera (GSC). MAXI/GSC detected the emission ∼45 s prior to the main burst episode observed by the CGBM. The MAXI/GSC and the CGBM spectrum of this prior emission period is fitted well by a blackbody with temperature 1.0 +0.3-0.2 keV plus a power law with a photon index of -1.6 ± 0.3. We discuss the radius of the photospheric emission and the main burst emission based on the observational properties. We stress the importance of coordinated observations via various instruments collecting high-quality data over a broad energy coverage in order to understand the GRB prompt emission mechanism