Exercise stress echocardiography using supine bicycle was performed and a variety of Doppler parameters were measured at baseline,

at each stage of exercise, and during recovery. There was a significant difference in E/E’ parameter, that is an index of LV filling pressure, in MetS Imatinib clinical trial patients at resting state. The increased E/E’ value was maintained during dynamic exercise test, which is similar to the result of a prior study.9) A unique result to this study is that LV longitudinal functional reserve, defined as the change Inhibitors,research,lifescience,medical in tissue Doppler imaging (TDI), S’ (longitudinal tissue velocity) from baseline to peak exercise was significantly lower in MetS patients even though there was no significant difference in baseline TDI S’ velocity between the Inhibitors,research,lifescience,medical two. After adjusting for known CV risk factors, an independent relationship between the presence of MetS and LV systolic functional reserve was observed. The recent use of TDI, strain, and strain rate at resting state allows Inhibitors,research,lifescience,medical detecting earlier subclinical dysfunction and providing essential mechanisms in understanding the development of heart failure. In addition, TDI parameters such as S’, E’, A’, and E/E’ have been known to have independent prognostic values in various cardiac diseases,10) even in low risk population.11) However, there is a study showing that resting LV TDI parameter did

not add any incremental prognostic impact over the clinical data in patients with type 2 Inhibitors,research,lifescience,medical DM.12) Thus, even though exercise capacity is already recognized as a significant predictor of CV diseases, the LV TDI measurements acquired by stress echocardiography seem to be more reliable and stronger in detecting the presence of subclinical CV disease13) and predicting clinical outcome,12) Inhibitors,research,lifescience,medical compared with resting TDI values. Nevertheless, measuring Doppler parameters

including TDI during exercise stress echocardiography for the evaluation of longitudinal diastolic functional reserve is still challenging, especially at peak stress, because the mitral velocities summate as the heart rate increases. In this study, no differences in longitudinal diastolic functional reserve may be due to these limitations in addition to a small sample size. Although the exact mechanism related to abnormal contractile reserve in patients with MetS is still unknown, it seems that multiple Carfilzomib factors including sympathetic nervous system, renin-angiotensin-aldosterone system, myocardial metabolism, and coronary flow reserve contribute to subclinical dysfunction of longitudinal myocardial contraction during exercise. In summary, MetS is associated with LV systolic and diastolic dysfunction at resting state and decreased LV longitudinal contractile reserve during exercise despite of similar values at baseline examination.