Patients who suffered a sudden blockage of the coronary arteries that supply blood to the heart muscle may not need to keep taking beta blockers once stent procedures and other treatments have restored heart function and their condition has stabilized, according to a new study.
Samsung Medical Center said on the 4th that a team led by Han Joo-yong and Choi Ki-hong of the Division of Cardiology and Kang Dan-bee of the Center for Clinical Epidemiology confirmed the possibility of discontinuing beta blockers in heart attack patients, in a joint study with a team led by Professor Johanne Silvain at Pitie-Salpetriere Hospital of Sorbonne University, part of the Assistance Publique-Hopitaux de Paris (AP-HP).
A heart attack is an emergency condition in which the coronary arteries supplying blood to the heart muscle become suddenly blocked by a blood clot or spasm, causing the heart muscle to die. In clinical practice, patients who have had a heart attack have long been assumed to need beta blockers for life. The drugs, used to treat high blood pressure, selectively block beta receptors of the sympathetic nervous system to slow the heart and lower blood pressure, ultimately easing the burden on the heart. But as reperfusion treatments such as percutaneous coronary intervention (PCI) have advanced, questions have been raised about whether long-term use is necessary for patients who have taken beta blockers for more than a year after a heart attack and remain relatively stable, without left ventricular systolic dysfunction or heart failure. Long-term use of beta blockers can also cause fatigue and dizziness or slow the pulse excessively, a point of long-standing debate in the field.
The researchers conducted a pooled analysis of the SMART-DECISION study previously carried out in Korea and France's ABYSS study. The subjects were 6,238 patients who were at least six months past a heart attack, had no problems with heart function such as heart failure, and had no other reason, such as high blood pressure, to take beta blockers.
The team divided them into a group that discontinued beta blocker treatment (3,092 patients) and a group that continued treatment (3,146 patients), and followed them for three years. Events such as death, a diagnosis of heart attack or stroke, or hospitalization for cardiovascular disease occurred in 17.2% of the discontinuation group and 15.9% of the continuation group, a difference that was not statistically significant. The share of patients who died or were hospitalized for a heart attack or heart failure was also similar, at 6.5% in the discontinuation group and 6.4% in the continuation group. That means heart attack patients whose heart function has recovered and who have entered a stable phase faced no greater risk of serious cardiovascular disease even after stopping the drugs.
Choi, the first author of the study, said treatment options for heart attacks were once limited, which is why beta blockers had to be taken for life. "Recently, as treatments such as stent procedures have advanced, more patients have recovered heart function after a heart attack and remain stable," he said. "Discontinuing unnecessary medication will help reduce the burden on patients, including side effects from long-term use."
In March, the Samsung Medical Center team had already published findings in the New England Journal of Medicine (NEJM) showing that patients whose heart function is stable after treatment for a heart attack see no difference in outcomes if they stop taking beta blockers. That randomized controlled trial, involving 25 hospitals in Korea, prompted discussion in the field that prescribing standards for beta blockers, followed as convention for decades, should be reviewed. The latest study, conducted jointly with France, was selected as the most notable clinical study at the recent annual meeting of the European Society of Cardiology in Munich, Germany, and was published in The Lancet. The findings are seen as further raising the likelihood that global guidelines for treating heart attacks will be revised on beta blocker use.
Han said the large-scale international joint study brought the field a step closer to establishing a treatment standard under which patients can stop taking beta blockers if they are stable after a heart attack. "I hope this becomes an opportunity to build a culture of using drugs only for patients who truly need them, based on reasonable and scientific standards," he said.
