Independent relationship of left atrial size and mortality in patients with heart failure: an individual patient meta-analysis of longitudinal data (MeRGE Heart Failure)
1 Section of Cardiology, Department of Surgical and Biomedical Sciences, University of Verona, Ospedale Maggiore, Ple Stefani 1, 37126 Verona, Italy
2 Divisione di Cardiologia, Fondazione Salvatore Maugeri, IRCCS, Veruno, Italy
3 Department of Cardiology, The Karoliska Institute, Hospital de Torrevieja, Spain
4 Unità Malattie Cardiovascolari 2, Ospedale Santa Chiara, Pisa, Italy
5 Divisione di Cardiologia, Fondazione IRCCS Policlinico S. Matteo, Pavia, Italy
6 The George Institute, University of Sydney, Sydney, Australia
7 Cleveland Clinic Foundation, Cleveland, OH, USA
8 Cardiac Investigation Unit, St Vincent's Hospital Melbourne, Melbourne, Australia
9 Division of Cardiology, Department of Medicine and Therapeutics, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China
10 Department of Medicine, FMHS, The University of Auckland, Auckland, New Zealand
* Corresponding author. Tel: +39 045 812 3706, Fax: +39 04 591 4727, Email: andrea9rossi{at}hotmail.it
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Abstract |
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Aims: Left atrial (LA) size is considered a marker of poor prognosis in heart failure (HF) patients. Prior studies have recruited relatively few subjects limiting their power to adequately analyse the interaction between LA size, left ventricular (LV) systolic and diastolic function, and prognosis.
Method and results: The MeRGE collaboration combines prospective data from 18 studies in HF patients. In this analysis of data from 1157 patients, the primary endpoint was death or hospitalization for worsening HF. In multivariate analysis (Cox proportion hazard model), LA area was associated with prognosis (HR 1.03 per cm2, 95% CI 1.02, 1.05; P < 0.0001) independently of age, NYHA class, LV ejection fraction, and restrictive filling pattern (RFP). When LA area was used as a categorical variable, the HR associated with larger LA area (above median) was 1.4 (95% CI 1.13, 1.74) and when LA area index was used, the HR was 2.36 (95% CI 1.80, 3.08). When the patients with and without RFP were divided on the basis of either LA area or LA area index, significantly higher event rates were observed in those with larger LA area.
Conclusion: Left atrial area is a powerful predictor of outcome among HF patients with predominantly impaired systolic function, and is independent of, and provides additional prognostic information beyond LV systolic and diastolic function.
Key Words: Left atrium • Heart failure • Diastolic function • Prognosis
Received February 16, 2009; Revised May 30, 2009; Accepted June 25, 2009
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