1. Department of cardiology, Teaching University Hospital of Brazzaville, PO Box 32, Brazzaville, Congo
2. Department of doctoral studies, Faculty of Health Sciences, Marien Ngouabi University, PO Box 2672, Brazzaville, Congo
3. Congolese Heart Society, Teaching University University of Brazzaville, 13 Bd Auxence Ikonga, Po Box 32, Brazzaville, Congo
4. WHO-Congo, Avenue du Charles de Gaulle, Centre ville, Po Box 2465, Brazzaville, Congo
5. Imperial Clinical Trials Unit, Imperial College London, Stadium House, 68 Wood Lane, London W12 7RH, UK