Largest International Registry of Stable Coronary Artery Disease Shows That Many Patients Have too High Baseline Resting Heart Rate

PARIS, August 29, 2011 /PRNewswire/ --

Results from CLARIFY, the largest international registry ever carried out in stable coronary artery disease (CAD) outpatients, show that despite the widespread use of β-blockers, one third of CAD patients had a resting heart rate (HR) of 70 bpm,^[1] a rate that has previously been shown to be linked with higher prevalence and severity of angina and heart attacks.^[2] The CLARIFY results, representing more than 30 000 patients from 45 countries worldwide, are presented today at the European Society of Cardiology congress.

CAD remains the leading cause of death worldwide.^[3] Improved understanding of the management and outcomes of these patients is paramount to reducing the disease burden.

The CLARIFY (ProspeCtive observational LongitudinAl RegIstry oF patients with stable coronary arterY disease) registry was designed to increase our knowledge and understanding of CAD, including an assessment of the role that HR plays in the prognosis of CAD patients. It aims to improve disease management by identifying gaps between existing evidence and actual practice.

CLARIFY enrolled 33 649 patients worldwide between November 2009 and July 2010. The mean age of patients, 77.5% of whom were men, was 64±11 years. The average pulse HR was 68.3±10.6 bpm, while the ECG-derived HR was 67.2±11.5 bpm. 44% of the patients had a resting HR ≥ 70 bpm. In addition, in adjusted analyses, HR >70 bpm was independently associated with a higher prevalence and severity of angina, and with more frequent evidence of ischemia.

"We have known for some years that heart rate is a potentially important risk factor in CAD, but until now, there was relatively little information regarding heart rate among CAD patients outside of hospital," says CLARIFY chairman Professor Gabriel Steg from the Hôpital Bichat in Paris, France. "For the first time, we can see that many patients with CAD have too high resting heart rate levels, and combined internal evidence from CLARIFY and external evidence from prior sources indicate that this is associated with worse symptoms and worse clinical outcomes.These findings suggest tighter control of baseline heart rate with heart-rate-lowering medications may benefit CAD patients by improving symptom control and outcomes."

Aspirin and statins were taken by more than 90% of patients and β-blockers by 75%, indicating widespread uptake of evidence-based medication for secondary prevention. "It is encouraging to see that the majority of CAD patients receive treatments in line with management guidelines," says Professor Steg. "The results presented today are just the beginning-CLARIFY has a prospective five-year follow-up planned and every year we will gather important information."

The CLARIFY registry is funded by an educational grant from Servier. Data is being collected and analysed at the Robertson Centre for Biostatistics in Glasgow, UK, under the guidance of Prof Ian Ford, and the study is being led by an academic executive steering committee chaired by Prof P. G. Steg.

Notes to Editors

Coronary artery disease (CAD)

Coronary artery disease, also known as ischemic heart disease, is the most common type of heart disease. CAD is the leading cause of death worldwide and is predicted to remain so for the next 20 years.^[3] Approximately 3.8 million men and 3.4 million women die from CAD each year,^[4] and in 2020, it is estimated that this disease will be responsible for a total of 11.1 million deaths globally.^[3]

CAD can remain undetected for years and manifest suddenly as an acute heart attack. Although CAD can be a silent disease, in the majority of patients it is symptomatic. It causes angina-chest pain evoked by exercise and other factors-and may lead to heart failure, which has a huge impact on quality of life. Despite lifestyle modifications and advances in medical management, CAD remains a global health problem and there is a need for new and effective preventative treatments.

Cardiovascular disease patient registries

Access to data (on modes of therapy, types of intervention, treatment regimens and outcomes across as large a patient population as possible) is a valuable asset in working towards defining gold standard treatment for cardiovascular disease management. Patient registries (prospective health surveys) are one of the key sources of these data.

References

^[1] Steg G. Heart rate, anginal symptoms, and the use of beta-blockers in stable coronary artery disease outpatients. The CLARIFY registry. ESC 2011, Abstract number 2092.

^[2] Fox K, Ford I, Steg PG, Tendera M, Robertson M, Ferrari R; BEAUTIFUL Investigators. Heart rate as a prognostic risk factor in patients with coronary artery disease and left-ventricular systolic dysfunction (BEAUTIFUL): a subgroup analysis of a randomised controlled trial. Lancet. 2008;372:817-821.

^[3] Mathers CD, Loncar D. Projections of global mortality and burden of disease from 2002 to 2030. PLoS Med. 2006;3:e442.

^[4] WHO. The global burden of disease: 2004 update. Available at: http://www.who.int/healthinfo/global_burden_disease/2004_report_update/en/index.html.