Cardiac resynchronization therapy (CRT) is an established treatment for symptomatic chronic heart failure (HF) patients with cardiac dyssynchrony. Since CRT is considered as one of the treatments for HF, several endpoints about HF improvement are often used to assess the therapeutic effects of CRT. However, identification of the HF precipitating factor that CRT can attenuate is crucial because HF can be attributed to multiple predisposing factors. The precipitating factor targeted by CRT is cardiac dyssynchrony. Cardiac dyssynchrony can be classified into electrical cardiac dyssynchrony and mechanical cardiac dyssynchrony, but CRT directly affects electrical cardiac dyssynchrony. Mechanical cardiac dyssynchrony can be indirectly alleviated by CRT as a result of improvement of electrical cardiac dyssynchrony. Therefore, recent guidelines about cardiac pacing does not recommend pre-procedural echocardiographic assessment of cardiac dyssynchrony to indicate CRT or to predict CRT outcome. Because electrical cardiac dyssynchrony is an adequate index for CRT indication, CRT can be applicable not only for patients with left bundle branch block, but also patients with other electrical cardiac dyssynchrony beyond current guideline recommendations. Identifying the site of the latest activation site in left ventricle, subsequent placing a left ventricular lead at that site, and appropriate device programming, may significantly expand indications for CRT.

　Background: The current situation regarding dyslipidemia in the working-age population and its relationship to other cardiovascular risk factors remain unclear.

　Participants and Methods: Changes in cardiovascular risk factors observed in 3,580 employees attending regular health checkups in 2010 and 2020 were investigated. Risk factors were compared in patients not taking any medication for dyslipidemia (P－group, n ＝ 2, 929) and those who were taking such medication (P ＋ group, n ＝ 651) in 2020 and also among job categories. In addition, low-density lipoprotein cholesterol (LDL-C) values (mg/dL) in 2010 were divided into 5 categories (A: ＜ 120, B: 120‒139, C: 140−159, D: 160−179, and E: ≧ 180) and any change determined in 2020.

　Results: 1) Although there was no difference in LDL-C among job categories, body mass index (BMI) and HbA1c were high in the station worker group; age was low in the train operator group; and systolic blood pressure (SBP), diastolic blood pressure, and estimated glomerular filtration ratio (eGFR) were low in the office worker group. 2) With or without drug treatment, there was a significant increase in BMI, HbA1c, SBP, uric acid, and eGFR, but the rate of increase in BMI and HbA1c was only marked in the P ＋ group. 3) In 2020, the proportion of patients with HbA1c ≧ 6.5％ or being prescribed for diabetes mellitus was approximately four times higher in the P＋group than in the P－group. 4) LDL-C in the P＋group increased from 2010 to 2020 in category A, but decreased significantly in categories B, C, D, and E. Also, in the P − group, a significant increase in LDL-C was observed in category A, and significant decreases in categories C, D, and E.

　Conclusion: The present results highlight the current situation regarding dyslipidemia in working-age people and the usefulness and problems of medical treatment. We conclude that these results should be considered when discussing treatment strategies for dyslipidemia.