COPERNICUS Proves Value of β-Blocker Carvedilol in Severe Heart Failure
The landmark Carvedilol Prospective Cumulative Survival (COPERNICUS) trial demonstrated the value of adding the β-blocker carvedilol to conventional treatment for patients with heart failure who also have symptoms with minimal exertion.
In the study, reported in this week’s issue of Circulation (Circulation. 2002;106:2194–2199), investigators led by Milton Packer, MD, from the College of Physicians and Surgeons at Columbia University in New York, NY, reported that carvedilol reduced the severity of heart failure, as well as the risk of clinical deterioration, hospitalization, and other serious clinical events. The study involved 2289 patients with severe heart failure and an ejection fraction of <25% who were randomized to receive either carvedilol or placebo for an average of 10.4 months. The double-blind, randomized, placebo-controlled trial had 1133 patients in the placebo group and 1156 in the carvedilol group.
Researchers found that patients who received carvedilol spent 27% fewer days in the hospital for any reason and 40% fewer days in the hospital for heart failure. The combined risk of death or hospitalization for a cardiovascular reason in the drug group was reduced by 27%, and the combined risk of death or hospitalization because of heart failure by 31%, compared with the placebo group. Patients in the treatment group were less likely to experience a serious adverse event, such as worsening heart failure, sudden death, cardiogenic shock, or ventricular tachycardia. The trial was stopped early because of the significantly beneficial effect of carvedilol on the patients’ health.
In an accompanying editorial (Circulation. 2002; 106:2164–2166), Kai C. Wollert, MD, and Helmut Drexler, MD, of the Hannover Medical School in Hannover, Germany, noted: “These data are impressive and indicate that, similar to patients in the earlier stages of the disease, patients with severe heart failure derive substantial benefit from anti-adrenergic therapy not only in terms of reduced mortality but also reduced morbidity.”
However, they said, “Not all β-blockers are created equal.” Some β-blockers differ in their abilities to block specific adrenergic receptors and some have ancillary properties, they wrote.
“Only direct head-to-head comparisons will answer the question of whether any particular β-blocker offers advantages over others,” they noted. “In the future, our most important goal may be to bridge the gap between the wealth of knowledge that has been derived from clinical heart failure trials and the less-than-perfect way many heart failure patients are still being treated in the community. The implementation of treatment strategies with proven efficacy in the medical community requires education of both healthcare providers and patients.”
Mutations in Two Genes Linked to Heart Failure
Polymorphisms in β1- and α2c-adrenergic receptors increase the risk of heart failure among black individuals. The marked increase in risk occurred when individuals had both variants, according to the authors of a report in the October 10, 2002 issue of the New England Journal of Medicine (N Engl J Med. 2002;347:1135–1142).
The researchers, led by Kersten M. Small, PhD, and Lynne E. Wagoner, MD, of the University of Cincinnati, in Cincinnati, Ohio, performed genotyping at the location of the β1-adrenergic receptor (β1Arg389) and α2cDel322-325 in 159 patients with heart failure and in 19 controls.
Among black subjects who were homozygous for α2cDel322-325 as compared with those with other α2c-adrenergic receptor genotypes, the increased risk was 5.65. There was no increased risk with β1Arg389 alone, but when subjects were homozygous for both variants, the odds ratio was 10:11. There were too few white patients who were homozygous for both polymorphisms to assess risk, according to the researchers.
The researchers concluded that the two variations of the genes act together synergistically to increase the risk of heart failure among blacks, a factor that might be useful in identifying individuals at risk.
Arthur M. Feldman, MD, Chairman of the Department of Medicine at the Jefferson Medical College in Philadelphia, Pa, told the New York Times in its October 10, 2002, issue, “This is the next era of care for heart failure patients.”
Automated External Defibrillators Save Lives in Untrained Hands
Automated external defibrillators (AED) at 3 US airports—O’Hare, Midway, and Meigs Field—were used to resuscitate 11 patients with ventricular fibrillation, including 8 who regained consciousness before they were admitted to the hospital, according to researchers from the city of Chicago, Ill, the Chicago Fire Department, The University of Texas Southwestern Medical Center in Dallas, Tex, and the Division of Emergency Medicine at the University of Chicago (N Engl J Med. 2002;347:1242–1247).
The researchers reported that 21 patients had nontraumatic cardiac arrests during the two-year study. Of these, 18 had ventricular fibrillation. Four patients suffered their arrest too far from the AED and none survived. Three remained in fibrillation and eventually died, even though the AED were used quickly. No shock was delivered in 4 cases of suspected cardiac arrest because the device correctly indicated that the patient was not in ventricular fibrillation.
Those who rescued 6 of the 11 patients who were successfully resuscitated had no training or experience with the AED, although 3 had medical degrees. Of the 18 patients with ventricular fibrillation, 10 were alive and neurologically intact at 1 year, the researchers reported.
Parents’ Stress Related to Behavioral Problems in Children With Corrected Heart Defects
The stress parents feel in caring for children who have undergone surgery to correct a congenital heart defect can result in behavioral problems in the youngsters, according to researchers from the Children’s Hospital and Harvard Medical School in Boston, Mass, in a report in the Journal of Developmental and Behavioral Pediatrics (J Dev Behav Pediatr. 2002;23:314–321).
Karen J. Visconti, PhD, and her colleagues monitored both 153 children born with transposition of the greater arteries and their parents for 4 years. The children had all had their heart defect corrected before the age of 3 months.
Parents responded to questionnaires about stress and social support when the children were 1 and 4 years of age. When they were age 4, their parents recorded all the behavioral and emotional problems in their children.
Dr Visconti said that the self-reported stress of the parents during the first 3 years of their children’s lives was the best predictor of behavioral problems in the youngsters by age 4. Those families with less social support reported more stress on their questionnaires.