While increased arterial stiffness is a known risk of cardiovascular disease, pulse wave velocity (PWV) is a conventionally adopted index of arterial stiffness. However, the relationship between PWV and left ventricular functions are not thoroughly evaluated. This cross-sectional study investigated whether PWV measurement is an early indicator of left ventricular (LV) dysfunction. A noninvasive, volume-plethysmographic apparatus was used to determine blood pressure, electrocardiogram, heart sounds, and PWV in 42 consecutively diagnosed subjects with hypertension, and 42 sex- and age-matched nonhypertension subjects were studied. Arterial stiffness and aortic stiffness were evaluated by brachial-ankle (b-a) PWV, heart-carotid (h-c) PWV, heart-femoral (h-f) PWV, carotid-femoral (c-f) PWV, and femoral-ankle (f-a) PWV. Function of LV was estimated by tissue Doppler imaging (TDI) echocardiography. Hypertension subjects exhibited higher b-a PWV and late diastolic mitral flow velocity values than those of nonhypertensive subjects. Pearson correlation analysis revealed that LV diastolic function (Em(av)) negatively correlated with c-f PWV and b-a PWV. Multiple linear regression analysis indicated that b-a PWV was independently and negatively associated with LV diastolic function (Em(av)). Further analysis by stratified hypertensive status, the b-a PWV were independently and negatively associated with Em(av) in hypertensive subjects (p = 0.004) only. In conclusion, the b-a PWV, but not c-f PWV, h-c PWV, h-f PWV, or f-a PWV, is significantly correlated with LV diastolic function in hypertensive subjects, indicating that b-a PWV involving both central and peripheral components of arterial stiffness may be an early indicator of LV dysfunction.

Level V.

It is important for Taiwanese policy makers to understand how economic factors affect US tourists' decision to travel to Taiwan. For the long-run analysis, Johansen's cointegration test reveals that three cointegration vectors exist among the model variables, indicating a long-run relationship. To conduct a short-run analysis, this paper employs vector auto regression (VAR) to estimate the responses of US tourists in Taiwan to the shocks of changes to personal disposable income, cost of living, and substitute price. The short-run equilibrium adjustment processes are discussed in terms of generalized impulse response. The results show an immediate and signifi cant response of changes in tourist arrivals to their own impacts, changes in the cost of living, and changes in the substitute price. In addition, the price, income, and cross-elasticity of tourism demand are all positive at the beginning of the responses, implying that the tourism products can be attributed to normal and substitute goods.