New study on LVH
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 New York-Presbyterian Hospital/Weill Cornell Medical Center in New York City.
An estimated 20% 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 New York-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 New York-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%). Among these patients, a greater than average reduction of LVH was associated with a 43% reduced risk of heart failure, and remained associated with a 36% 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% of new heart failure cases in men and 59% 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.