Preventing enlarged heart reduces heart failure

Sep 11 2007

For high-blood-pressure patients, preventing or reducing enlarged heart (left ventricular hypertrophy or LVH) reduces risk of heart failure. The study is published in the Sept. 4 Annals of Internal Medicine and led by physician-scientists at NewYork-Presbyterian Hospital/Weill Cornell Medical Center in New York City.

An estimated 20 percent of all high-blood-pressure patients, or 12 million Americans, have LVH and are at increased risk of developing heart failure.

While the direct relationship between levels of LVH in patients with high blood pressure and risk of cardiac complications -- including death, heart attack, stroke and atrial fibrillation -- has previously been demonstrated by NewYork-Presbyterian/Weill Cornell researchers (JAMA, 2004 and 2006), the new study is the first to demonstrate that prevention or regression of LVH reduces risk of being hospitalized for heart failure -- and that this relationship exists independent of therapy type and the benefits of blood pressure reduction. The study uses data from the Losartan Intervention for Endpoint Reduction in Hypertension (LIFE) study conducted between 1995 and 2001.

"The message for high-blood-pressure patients is that by preventing or reversing enlarged heart, there is an added benefit, over and above any reduction in blood pressure, of lowering risk for heart failure," says the study's principal investigator, Dr. Peter Okin, director of clinical affairs and professor of medicine in the Greenberg Division of Cardiology at Weill Cornell Medical College and a cardiologist at NewYork-Presbyterian/Weill Cornell.

"And, from a public health perspective, our findings suggest that blood-pressure therapy targeted at regression or prevention of LVH may help to blunt the increasing incidence of heart failure," continues Dr. Okin.

Of the 8,479 high-blood-pressure patients without heart failure followed in the new study, 214 were hospitalized for heart failure (2.5 percent). Among these patients, a greater than average reduction of LVH was associated with a 43-percent reduced risk of heart failure, and remained associated with a 36-percent reduced risk after adjusting for other risk factors. Levels of LVH were determined by electrocardiograph (ECG) using Cornell voltage-duration product criteria. (Cornell voltage-duration product, an ECG pattern associated with presence of LVH, was developed at Weill Cornell Medical College in 1992 and is currently in use worldwide.)

Previous studies have shown that hypertension doubles the lifetime risk for developing heart failure in men and triples the risk in women, accounting for 39 percent of new heart failure cases in men and 59 percent of incident cases in women.

All patients in the LIFE study received Losartan- or atenolol-based therapies. In a previous LIFE study paper (Circulation, 2003), Weill Cornell researchers found the angiotensin receptor antagonist drug Losartan had a decided advantage over another anti-hypertensive drug, the beta-blocker atenolol, in reducing LVH.

Co-authors of the new study include Dr. Richard Devereux (professor of medicine at Weill Cornell Medical College and director of the NewYork-Presbyterian/Weill Cornell Echocardiography Laboratory and Non-Invasive Cardiac Imaging Program) and physician-scientists from Amgen Inc. (San Francisco); Merck Research Laboratories (West Point, Pa.); Sahlgrenska University Hospital/Östra (Sweden); University of Oslo (Norway); Ullevål University Hospital (Norway); and University of Michigan Medical Center (Ann Arbor).

Dr. Devereux is a member of a cardio-renal advisory board for Merck and as such receives income for lectures and consulting.

The study was supported, in part, by a grant from Merck & Co. Inc., West Point, Pa.

Left Ventricle Hypertrophy

Chronic high blood pressure can lead to left ventricular hypertrophy (LVH), a dangerous enlargement of muscle surrounding the heart's main pumping chamber. The condition can be monitored via electrocardiograph -- an inexpensive, widely available heart test that measures the nature and speed of electrical impulses within cardiac muscle.

Heart Failure

Heart failure is a progressive disorder in which damage to the heart causes weakening of the cardiovascular system. It manifests by fluid congestion or inadequate blood flow to tissues. Heart failure progresses by underlying heart injury or inappropriate responses of the body to heart impairment. It is estimated that nearly 5-million Americans have heart failure. The prevalence of the disease approximately doubles with each decade of life. Men and women have a one-in-five chance of developing heart failure in their lifetime.

NewYork-Presbyterian Hospital/Weill Cornell Medical Center

NewYork-Presbyterian Hospital/Weill Cornell Medical Center, located in New York City, is one of the leading academic medical centers in the world, comprising the teaching hospital NewYork-Presbyterian and its academic partner, Weill Cornell Medical College. NewYork-Presbyterian/Weill Cornell provides state-of-the-art inpatient, ambulatory and preventive care in all areas of medicine, and is committed to excellence in patient care, research, education and community service. NewYork-Presbyterian, which is ranked sixth on the U.S.News & World Report's list of top hospitals, also comprises NewYork-Presbyterian Hospital/Columbia University Medical Center.