Baseline information of all eligible candidates, including age, gender, body mass index (BMI), and disease duration were recorded. Serum low-density lipoprotein (LDL), creatinine (Cre), high sensitivity C-reactive protein (hs-CRP), glycohemoglobin (Hba1c), and b-type natriuretic peptide (BNP) were evaluated during the follow-up. Each blood sampling for BNP analysis and short form-36 health survey (SF-36) of physical component score (PCS) and mental component score (MCS) for qualities of life were performed just before each cardiopulmonary exercise test and echocardiographic examination.