- Addition of valsartan to an angiotensin-converting enzyme inhibitor improves cardiac sympathetic nerve activity and left ventricular function in patients with congestive heart failure. Kasama, S., Toyama, T., Kumakura, H., Takayama, Y., Ichikawa, S., Suzuki, T., Kurabayashi, M. J. Nucl. Med. (2003)