Faster heart rate linked to increased heart attack risk

Sep 1 2008

A long-term study has revealed a link between a faster heart rate and the risk of a heart attack and the researchers say that heart disease patients with a pulse of more than 70 beats a minute are most at risk.

In a four year study involving 11,000 patients in 33 countries, all with coronary disease, cardiologists have found that a faster than normal heartbeat significantly increases the risk of dying from a heart attack, heart failure, admission to hospital for heart attack, and coronary revascularisation.

The patients were taking regular cardiovascular medicine, and for the research 5,479 patients were also given ivabradine while 5,438 received a placebo.

Ivabradine inhibits the electrical currents which control the heart rate, but does not affect other aspects of cardiac function.

The researchers suspect that an increased heart rate possibly places the plaques, the narrowings that occur in coronary arteries at an increased risk by making it more likely for them to break open.

The study showed that lowering the heart rate with the drug ivabradine reduced the incidence of cardiovascular disease and death in such patients by more than a third.

The researchers say by just lowering the heart rate the risk of a heart attack was reduced in patients with heart disease, which points to the need for research into the importance of the heart rate.

They believe this could have wider implications for a much broader population and could be significant as coronary heart disease remains one of the largest single causes of death and the most common cause of sudden death, in many countries.

The researchers found though heart patients are subjected to multiple investigations, all too often the simple heartbeat is not even measured yet it is clearly highly significant.

They say an elevated heart rate is a strong independent risk factor in patients with coronary artery disease and heart rate should be assessed in order that the best medical treatment can be provided to heart patients with a high heart rate.

They say reducing the heart rate with ivabradine could be used to reduce the incidence of coronary artery disease outcomes in patients who have heart rates of 70 bpm or greater.

The research was presented at a medical congress in Germany and is published in the British medical journal, the Lancet.