Optimising outcomes in end-stage heart failure: differences in therapeutic responses between diverse ethnic groups.

Clinical and pathophysiological differences between Japanese and Caucasian patients are observed in many aspects of heart disease. Indeed, data derived from studies in one population cannot be automatically extrapolated to the other. The therapeutic goal of heart failure has recently been aimed at improving mortality in Western societies. The long-term use of an inotropic agent in the energy-starved failing heart has been expected to increase myocardial energy use and accelerate the disease process. However, this may not be the case in the Japanese population in whom mortality is relatively low. Therefore, vesnarinone therapy could be justified, since it allows optimal care in terms of an improved quality of life. Nevertheless, re-analysis of the findings of the Vesnarinone Trial (VEST) emphasised again the reasons for the precautions relating to vesnarinone use: (i) vesnarinone was associated with increased death, usually occurring within 7 months of initiation of the drug; (ii) the mortality rate was higher in patients receiving concomitant digoxin, which necessitated close monitoring of renal function; (iii) the mortality rate also increased in patients with severe bradycardia, indicating the importance of regular ECG monitoring; and (iv) improvements in cardiac function and symptoms by the drug may result in sudden death, particularly in patients with severe heart failure. Such patients should be closely monitored by a physician.