left ventricular dysfunction
"This is a tough med to start. But after a few weeks I got adjusted and titrated up to the right dose.  My EF was close to 35% when I started it. When I began taking this drug I would get dizzy which would instill panic episodes in me.  But I stuck with it and my EF is 55% now. I now don't even notice the Coreg unless I forget it. And when I do forget it, I get a little jittery. It's a miracle drug. Tough to start but worth the result."