Navigation Links
Double duty for blood pressure drugs: how they could revolutionize how we treat valve disease
Date:10/24/2011

Vancouver A type of medication known as angiotensin-receptor blockers could reduce risk of mortality in people with a heart disease called calcific aortic stenosis (AS) by 30 per cent over an eight-year period, Heart and Stroke Foundation researcher Dr. Philippe Pibarot told delegates at the Canadian Cardiovascular Congress. The condition is currently managed with open heart surgery.

"Our discovery shifts how we think about AS by looking at a new pathway which both prevents and reverses calcification," says Dr. Pibarot, a professor at Laval University and Canada Research Chair in Valvular Heart Diseases, Qubec Heart & Lung Institute. "It broadens how we can approach therapies, opening up new avenues of research, and has tremendous potential to lead to a major discovery."

From a health economics point of view, drug treatment is also far less expensive than replacing a valve through surgery, which Dr. Pibarot says costs at least $30,000.

Every year, AS is responsible for 10,000 to 15,000 deaths in North America, and upwards of 80,000 heart surgeries. Now, this promising research suggests the first possible drug therapy to treat AS.

"AS is one of the most common types of heart disease, yet the only option to save lives has been open heart surgery. And valve replacement surgery is the second most frequent heart surgery after coronary artery bypass," says Dr. Pibarot. "We may be able to slow the progress of AS to the point that most people won't need surgery."

Picture a normal heart valve as soft and thin, like a slice of tomato, Dr. Pibarot says. Compare that to a valve that has hardened and narrowed more like a cauliflower. That's calcific AS, the most common type of AS, where deposits of calcium form in the valve, which prevents it from opening properly and creates a dangerous 'pressure overload' within the heart.

For years, he notes, the assumption was that AS was a degenerative disease related to aging and the cumulative wear and tear on a heart valve. But more recent studies have indicated that AS development also has some genetic and lifestyle factors (such as obesity).

As a result, several trials have looked at whether statins (a class of drugs used to lower cholesterol levels) could also be effective against AS. Those results have not been promising. Dr. Pibarot and colleagues took another approach, examining medication that is typically used to treat high blood pressure (hypertension).

The renin-angiotensin system (RAS), specifically a molecule called angiotensin II, is a major target for drugs that lower blood pressure. Some hypertension drugs block the production of angiotensin II itself they are known as angiotensin-converting enzyme inhibitors (ACE inhibitors). Other drugs focus on the receptors of angiotensin II angiotensin-receptor blockers (ARBs).

Over three-and-a-half years, Dr. Pibarot's study followed 340 patients who had AS, 73 per cent of whom also had some degree of hypertension. Among the patients, 34 per cent were on ACE inhibitors, 16 per cent were on ARBs, and 50 per cent were on no RAS medication.

The follow-up involved measuring the velocity of the blood across the affected valve. As Dr. Pibarot explains, just as water flows faster when a river narrows, creating rapids, a narrowing valve raises pressure too. "A quicker blood velocity means the stenosis is progressing faster," he says.

Compared to the individuals who were on no medication, those who were on ACE inhibitors had less rapid narrowing of their valve. But the biggest difference was seen in patients on ARBs, where the receptors of angiotensin II are blocked. In those patients, the progress of the disease was slowed considerably three times slower than in the individuals who weren't taking any medication, reports Dr. Pibarot.

In effect, he says that with ARBs the current is slower, like on a calmer river.

In the absence of a drug treatment for AS, Dr. Pibarot's findings are potentially very significant, says Heart and Stroke Foundation spokesperson Dr. Beth Abramson.

"Open heart surgery can be effective, but is risky for many patients because of their age," says Dr. Abramson. "ARBs have the potential of slowing aortic stenosis significantly, so that we can prolong life without surgery."

She says that the need to find a medication solution is even more urgent when you consider that with the aging population the prevalence of valvular heart disease is expected to double within 15 years.


'/>"/>

Contact: Amanda Bates
amanda@curvecommunications.com
604-306-0027
Heart and Stroke Foundation of Canada
Source:Eurekalert

Related medicine news :

1. Pot Smoking May More Than Double Crash Risk
2. Marijuana use may double the risk of accidents for drivers
3. Capacity to diagnose osteoporosis doubles in Armenia
4. Smoking May Double Risk for Stroke
5. Study examining large-scale data of double balloon enteroscopy shows it is safe and effective
6. ADHD Doubles a Childs Risk of Injury: Study
7. Double damage: Partner violence impacts mental health of over half-million Californians
8. C-Sections Linked to Doubled Risk for Blood Clots
9. Infections Among Those With Heart Devices Has Doubled: Study
10. Bone marrow transplant survival more than doubles for young high-risk leukemia patients
11. Too Much Sitting May Double Womens Risk of Blood Clots
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/25/2016)... ... June 25, 2016 , ... First Choice Emergency Room , ... Sesan Ogunleye, as the Medical Director of its new Mesquite-Samuell Farm facility. , ... our new Mesquite location,” said Dr. James M. Muzzarelli, Executive Medical Director of First ...
(Date:6/25/2016)... ... 25, 2016 , ... Dr. Calvin Johnson has dedicated his ... implemented orthobiologic procedures as a method for treating his patients. The procedure is ... to perform the treatment. Orthobiologics are substances that orthopaedic surgeons use to help ...
(Date:6/25/2016)... , ... June 25, 2016 , ... Conventional wisdom preaches ... success. In terms of the latter, setting the bar too high can result in ... than just slow progress toward their goal. , Research from PsychTests.com ...
(Date:6/24/2016)... , ... June 24, 2016 , ... Those who have ... these feelings, many turn to unhealthy avenues, such as drug or alcohol abuse, as ... Michigan, has released tools for healthy coping following a traumatic event. , Trauma sufferers ...
(Date:6/24/2016)... ... , ... Marcy was in a crisis. Her son James, eight, was out of control. Prone ... physically. , “When something upset him, he couldn’t control his emotions,” remembers Marcy. “If ... at my other children and say he was going to kill them. If we ...
Breaking Medicine News(10 mins):
(Date:6/26/2016)... LAS VEGAS , June 26, 2016 ... movement to value-based care operating models within the health ... that enable greater financial efficiency , Deloitte offers ... address the key business issues impacting efficient cost optimization: ... alignment , These services facilitate better outcomes and ...
(Date:6/24/2016)... June 24, 2016 ... announced the addition of the " Global Markets ... This report focuses ... an updated review, including its applications in various applications. ... market, which includes three main industries: pharmaceutical and biotechnology, ...
(Date:6/24/2016)... 24, 2016 Research and Markets has ... Companion Diagnostic Tests" report to their offering. ... Diagnostics The World Market for Companion Diagnostics ... diagnostics. Market analysis in the report includes the following: ... Vitro Diagnostic Kits) by Region (N. America, EU, ROW), 2015-2020 ...
Breaking Medicine Technology: