May Increase Early Detection and Treatment of CHF
Jan 3, 2006
An electrocardiogram (ECG) is an effective tool for detecting risk of congestive heart failure (CHF) in patients with hypertension, according to a new study by physician-scientists at NewYork-Presbyterian Hospital/Weill Cornell Medical Center published in today's journal Circulation: Journal of the American Heart Association. The findings may help increase early detection and treatment of CHF.
An analysis of 8,696 hypertensive patients with no history of CHF found that a unique and well-known ECG wave pattern called strain was present in 923 patients (10.6 percent). These patients had a greater than threefold increased risk of developing CHF, with a five-year rate of 8.8 percent, compared with only 2.7 percent for those without ECG strain. Additionally, patients with strain had an exactly fourfold increased risk of CHF mortality, with a five-year CHF mortality of 1.2 percent, compared with only 0.3 percent in patients without strain.
"These findings suggest that more aggressive therapy may be warranted in hypertensive patients with ECG strain to reduce the risk of CHF and CHF mortality," says Dr. Peter Okin, the study's lead investigator, and professor of medicine and director of clinical affairs in the Greenberg Division of Cardiology at Weill Medical College of Cornell University. Dr. Okin is an attending physician at NewYork-Presbyterian/Weill Cornell.
The ECG strain pattern was first identified in 1949. The pattern has previously been strongly associated with left ventricle hypertrophy (LVH) independently of coronary heart disease and with an increased risk of cardiovascular morbidity and mortality in heart patients.
Compared with patients who did not develop CHF, patients who developed CHF were older; more likely to be black; more likely to have diabetes and a prior history of ischemic heart disease, heart attack, stroke, and peripheral vascular disease; more overweight; and more likely to be current smokers. The study found that after adjusting for these factors, presence of strain was still associated with increased risk of CHF.
Hypertensive patients routinely have ECGs performed, typically as part of an initial evaluation and then yearly to look for new abnormalities.
About five million Americans live with CHF, a condition in which the heart can't pump enough blood to the body's other organs. A healthy heart pumps 50 percent or more of the blood it receives in one beat; a failing heart pumps less. As blood flow out of the heart decreases, blood returning to the heart through the veins can back up, causing congestion in the tissues and/or lungs. Often, swelling (edema) results. If not successfully controlled, heart failure can cause serious disability and death.
About 50 million Americans live with hypertension, or high blood pressure. Hypertension is controllable with treatment. It requires lifelong monitoring, and the treatment may require adjustments periodically. In addition to CHF, complications from hypertension include heart attacks, blood vessel damage (arteriosclerosis), aortic dissection, kidney damage, kidney failure, and stroke.
The study's co-authors include NewYork-Presbyterian/Weill Cornell's Dr. Richard B. Devereux. Other participating study sites include Helsinki University Central Hospital (Finland), Sahlgrenska University Hospital (Göteborg, Sweden), Ullevaal University Hospital (Oslo, Norway), and University of Michigan Medical Center (Ann Arbor).
The study was funded in part by a grant from Merck of West Point, Pa.