A drug could replace surgery and reduce risk of mortality in people with the heart disease calcific aortic stenosis, Canadian researchers say. Dr. Philippe Pibarot -- a professor at Laval University and Canada research chair in valvular heart diseases, at Quebec Heart & Lung Institute -- told delegates at the Canadian Cardiovascular Congress the condition is responsible for 10,000 to 15,000 deaths in North America and about 80,000 heart surgeries each year. Pibarot said a normal heart valve is soft and thin, like a slice of tomato, but with the disease the valve becomes hardened and narrowed -- more like cauliflower -- because deposits of calcium form in the valve. This prevents it from opening properly creating a dangerous \"pressure overload\" within the heart, Pibarot said. The assumption was that aortic stenosis was a degenerative disease related to aging and the cumulative wear and tear on a heart valve. But recent studies indicated aortic stenosis had some genetic and lifestyle factors such as obesity, Pibarot said. Pibarot and colleagues tracked 340 patients with aortic stenosis, 73 percent of whom also had some degree of hypertension. Thirty-four percent were on ACE inhibitors, a hypertension drug, 16 percent were on angiotensin-receptor blockers, another hypertension drug, and 50 percent were on no hypertension medication. Compared to the individuals who were on no medication, those who were on ACE inhibitors had less rapid narrowing of their valve. Among patients on angiotensin-receptor blockers, disease was slowed considerably – three times slower than in the individuals who weren\'t taking any medication, Pibarot said.