My father's echo test shows his heart function only 18%, we always know he has weak valve due to last attack more than 10 years ago. But for the past 2 years, his condition got worse. He is currently not able to walk due to swollen legs. He consumes diuretic pill (Lasix) but seems it's not helping. Is there any medication that need to be changed? Does he have options for other medical actions beside stem cell?