Anaerobic Threshold (AT) has been commonly used for an exercise prescription in the health and clinical fields, and it is based on the underlying physiological mechanism of chemical energy supply and the O₂ transport system. Critical Power (CP) was recently proposed in sports science and is primarily used to estimate performance (i.e., power output). In this review, the detailed nature of CP, as derived from the power-duration hyperbolic curve, is introduced and discussed in terms of physiological responses during step exercise. The CP is distinctly higher than AT and plays an important role in dividing two categories of supra-AT exercise domains: “moderate” to sub-AT, “heavy” to between AT and CP, and “severe” to supra-CP. In addition, some interesting and clinically relevant topics about CP are discussed.

　Japan has become a super-aged society, and the number of patients with heart failure and many other cardiovascular diseases is rapidly increasing. Although the treatment of cardiovascular diseases is constantly evolving, most of them are symptomatic and not based on the cause of the disease, and therefore, they cannot be “cured”. Cardiovascular diseases are caused by a complex interplay of many environmental and genetic factors, and the pathogenesis of these diseases has not been fully elucidated. In addition, there are many modalities for diagnosing cardiovascular diseases, and the information obtained from these modalities is so vast that it has been difficult to analyze them fully. However, with the recent development of genomic and omics analysis technology, computers, and AI, it has become possible to analyze such complex and enormous information. In the future, it is expected that the pathophysiology of ultra-complex cardiovascular diseases will be elucidated, and molecular targeted therapy and precision medicine for each patient will be implemented based on the cause of the disease.

　Background: Subclinical leaflet thrombosis (SLT) has been reported after transcatheter aortic valve replacement (TAVR) in patients with severe aortic stenosis (AS). The details of the evaluation methods used are unclear, however.

　Objectives: This study evaluated post-TAVR SLT using multidetector row computed tomography (MDCT) and transthoracic echocardiography (TTE).

　Methods: The TAVR was performed in patients with severe AS at our hospital between September 2016 and October 2019. The 80 patients who were eligible for MDCT and TTE during early-period post-TAVR were evaluated for SLT.

　Results: Among the 80 patients eligible, MDCT performed during early post-TAVR revealed hypo-attenuated leaflet thickening (HALT) in 19 (24％), which was also observed with moderately or severely reduced leaflet motion (RELM) in 9 (11％). With TTE, however, prosthetic leaflet thrombosis could be detected in only 2 patients. The TTE findings in the HALT (＋) group were peak flow velocity, 2.25 ± 0.47 m/sec; mean pressure gradient, 10.9 ± 4.4 mmHg; effective orifice area (EOA), 1.47 ± 0.47 cm²; and an EOA index score of 1.01 ± 0.30 cm²/m². These findings were not significantly different between the HALT (＋) and HALT (−) groups.

　Conclusion: In the early post-TAVR period, 24％ of patients had HALT and 11％ had HALT with moderate or severe RELM on MDCT, indicating that additional MDCT in addition to TTE in the early post-TAVR period is more likely to detect SLT.

　Cardiac amyloidosis is often diagnosed following a physiologic examination. Some such cases are not diagnosed preoperatively, however. This report describes some such cases: an 84-year-old man in whom the diagnosis was made following a pathological examination of myocardium resected during surgery for severe aortic stenosis; a 78-year-old woman with a history of congestive heart failure where the diagnosis was made after a pathological examination of the left atrial appendage resected during surgery for severe mitral regurgitation; a 75-year-old man with a history of congestive heart failure in whom it was made after pathological examination of the left atrial appendage resected during surgery for deteriorated bioprosthetic mitral valve; and a 76-year-old man with a history of nephrotic syndrome in whom the diagnosis was made following pathological examination of the aortic wall resected during surgery for severe aortic stenosis and an ascending aortic aneurysm. All were subsequently referred for treatment of amyloidosis. Patients with a history of congestive heart failure often die of low output syndrome. The mortality rate in cases of heart failure accompanied by cardiac amyloidosis is very poor. Attention should be paid to the possibility of cardiac amyloidosis in differential diagnosis.