Surgery is no better than drugs to prevent serious complications of atrial fibrillation

Press release

Friday, March 15, 2019

The cardiac procedure has improved the quality of life and the symptoms of the patients.

Catheter ablation, a common cardiovascular procedure, does not seem more effective than drugs in preventing stroke, death, and other complications in patients with atrial fibrillation. However, patients who undergo the intervention experience much greater relief from symptoms and a long-term improvement in quality of life, including fewer recurrences and fewer hospitalizations than those who receive only medications . The results come from two new studies published in the March 15 issue of Journal of the American Medical Association.

The articles report the results of the CABANA (Catheter Ablation, Anti-Arrhythmic and Anti-Arrhythmic Drug Therapy) Trial, funded in part by the National Institutes of Cardiovascular and Pulmonary Health (NHLBI), part of the National Institutes of Health. This was a randomized trial comparing advanced drug treatments for atrial fibrillation – an irregular heartbeat – to ablation, a procedure in which a doctor inserts a catheter into the blood vessels of the patient to heal or destroy heart tissue at the origin of irregularities. .

"Given that current drug therapies often have limited effectiveness in controlling atrial fibrillation, it is very important to understand if ablation, an invasive procedure, gives better results," said David Goff, MD, Ph.D., Director of the Division of Cardiovascular Sciences. at NHLBI. "As these two documents show, CABANA has provided a wealth of information that physicians can use to better manage patients and improve their quality of life."

Atrial fibrillation, the most common cardiac arrhythmia, affects at least 2.7 million Americans and contributes significantly to strokes, congestive heart failure and even late cognitive impairment. Symptoms include rapid palpitations, in which the heart tips or jumps; tired; shortness of breath; and difficulty with physical exertion. While some patients have no symptoms, others suffer from a severely degraded quality of life. Some become extremely anxious and even handicapped by both the current symptoms and their unpredictability.

The CABANA trial researchers wanted to know which action plan – ablation or pharmacotherapy – would be best able to reduce the rates of death, disabling stroke, severe bleeding or cardiac arrest in these patients.

Since its launch in November 2009 until April 2016, CABANA has recruited more than 2,200 patients at 126 sites in the United States, Canada, Europe and Asia.

About half of the patients were randomly assigned to the ablation procedure. The other half was assigned to pharmacotherapy; but they could choose to undergo ablation if their symptoms could not be controlled. About 27% of patients in the drug treatment group were also ablated. The median follow-up period was 48.5 months.

"Although the trial data did not show that ablation was superior to drug therapy to reduce death and stroke rates, it showed a reduction in recurrence rates." atrial fibrillation, as well as a reduction in the number of hospitalizations, "said Yves Rosenberg, MD, program manager. the study and head of the atherothrombosis and coronary artery branch of NHLBI.

The overall rate of death and stroke was lower than expected; and about 9% of the people assigned to the ablation were not able to undergo the procedure. This could have affected the results of the study, according to Douglas L. Packer, MD, a cardiologist and professor of medicine at Mayo Clinic in Rochester, Minnesota, and the study's lead investigator.

"Most often, we look at clinical trial data by comparing results by randomly assigned group, but patients and physicians do not always follow the treatment assigned. When we examined the data according to the treatment actually received, the ablation group had significantly lower death rates as well as a combination of death, disabling stroke, severe bleeding or cardiac arrest compared to patients who received only medication, "said Packer. .

The data also showed a significant long-term improvement in quality of life, as well as a reduction in atrial fibrillation symptoms in patients in the catheter ablation treatment group. This was a key secondary objective of the CABANA research program. It had previously been shown that ablation of atrial fibrillation improved the quality of life compared to pharmacotherapy, but these preliminary studies had a limited sample size and a follow-up of a year or so. less.

"CABANA, because of its size and duration, provides extraordinarily new data from the patient's point of view," said Rosenberg.

Only 12 months after the start of treatment, the quality of life for patients in both groups improved significantly. However, those treated with ablation saw a greater decrease in atrial fibrillation symptoms, such as fatigue and shortness of breath, and these improvements in quality of life were sustained over the five years of follow-up.

Initially, 86% of patients in the ablated group and 84% on drug therapy reported atrial fibrillation symptoms in the previous month. At the end of the study, however, there had been a significant decrease in symptoms – with only 25% of patients with ablation arm reporting symptoms, compared with 35% of patients treated with only drug therapy.

The researchers also noted that patients with the most severe quality of life alterations at the time of enrollment in the study exhibited a significantly greater improvement after catheter ablation than patients with initially mild symptoms.

Study: Packer et al. Effect of catheter ablation versus antiarrhythmic therapy on 2 deaths, stroke, bleeding and cardiac arrest in patients with atrial fibrillation 3: CABANA randomized clinical trial. DOI: 10.1001 / jama.2019.0693

Study: Mark et al. Effect of catheter ablation or medical treatment on the quality of life of patients with atrial fibrillation: CABANA randomized clinical trial. DOI: 10.1001 / jama.2019.0692

About National Heart, Lung and Blood Institute (NHLBI): NHLBI is the world leader in leading and supporting research on heart, lung and blood diseases and sleep disorders that advances scientific knowledge, improves public health and saves lives. For more information, visit https://www.nhlbi.nih.gov.

About the National Institutes of Health (NIH):
The NIH, the country's medical research agency, has 27 institutes and centers and is part of the US Department of Health and Human Services. NIH is the lead federal agency that conducts and supports basic, clinical and translational medical research. She studies causes, treatments and cures for common and rare diseases. For more information on NIH and its programs, visit www.nih.gov.

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