High resting heart rate signals increased CV, death risk in stable CVD
MedWire News: Stable cardiovascular (CV) disease patients on optimal medical therapy are at increased risk for all-cause mortality and future cardiovascular events if their resting heart rate is greater than 70 beats per minute (bpm), analysis of two large trials shows.
The findings were presented at the Canadian Cardiovascular Society Annual Congress in Montréal, Quebec, where lead researcher Eva Lonn (McMaster University, Hamilton, Ontario, Canada) said: "Heart rate is measured routinely at every medical encounter, it's easy to do, it's cheap to measure, and we have good medications that can lower heart rate, so it is something we can treat.
"We are always looking for new ways to define which patients are at higher risk for developing vascular events."
Lonn and colleagues assessed the findings of the ONgoing Telmisartan Alone and in combination with Ramipril Global Endpoint Trial (ONTARGET) and concurrent Telmisartan Randomized Assessment Study in ACE intolerant Subjects with Cardiovascular Disease (TRANSCEND) trials.
In both trials, the rates of all-cause mortality and major vascular events (MVEs), defined as composite CV death, myocardial infarction, stroke, and hospitalized heart failure, were observed among a combined total of 31,531 patients aged at least 55 years, over a median follow-up period of 4 years.
All patients had stable CV disease with optimal medical treatment.
Lonn and team assessed the resting heart rates of all patients at baseline, and categorized them as high (>70 bpm) or low (≤ 70 bpm).
After adjustment for confounding risk factors such as smoking status and beta-blocker use, the researchers found that patients with a high resting heart rate had a 23% higher risk for MVEs than those with a low resting heart rate (p<0.0001).
Lonn et al observed a positive correlation between MVE risk and resting heart rates above 50 bpm. Above 64 bpm, each additional 10-bpm increase led to a further increase in MVE risk by at least 10% (p<0.0001).
Patients with a high resting heart rate were also found to have a 38% and 40% higher risk for CV and all-cause mortality, respectively, compared with those with a low resting heart rate (p<0.0001 for both).
Speaking at the same conference, Beth Abramson from the Heart and Stroke Foundation of Canada in Ottawa, Ontario, said: "This study on heart rate is intriguing but it is important that we are reminded how to truly reduce our future risk.
"Eating a balanced diet, being physically active, managing stress, limiting caffeine intake, and being smoke-free can help improve your heart health, regardless of the effects on heart rate."
She added, however, that further study into the association noted by Lonn et al is warranted.
MedWire (www.medwire-news.md) is an independent clinical news service provided by Current Medicine Group, a trading division of Springer Healthcare Limited. © Springer Healthcare Ltd; 2010
By Lauretta Ihonor