Objective: To compare baseline cardiovascular risk management between people from two different health-care systems recruited to a research trial of an intervention to optimise secondary prevention.Design: Cross-sectional study.Setting: 16 randomly selected general practices in Northern Ireland (NI) (UK NHS, strong infrastructure, pay-for-performance) and 32 in the Republic of Ireland (RoI) (mixed healthcare economy, less infrastructure, no pay-for-performance).Patients: 903 (mean age 67.5 years; 69.9% male) randomly selected patients with known coronary heart disease.Main outcome measures: Blood pressure (BP), cholesterol, medications; validated questionnaires for diet (DINE), exercise (Godin) and quality of life (SF-12); healthcare usage.Results: More RoI than NI participants had systolic BP.140 mm Hg (37% vs 28%, p = 0.01) and cholesterol >5 mmol/l (24% vs 17%, p = 0.02). RoI mean systolic BP was higher (139 vs 132 mm Hg). More RoI participants reported a high fibre intake (35% vs 23%), higher levels of physical activity (62% vs 44%) and better physical and mental health (SF-12); they also had more GP (5.6 vs 4.4) and fewer nurse visits (1.6 vs 2.1) in the previous year. Fewer participants in the RoI (55% vs 70%) were prescribed beta blockers. ACE inhibitor prescribing was similar for both groups (41%; 48%); high proportions were prescribed statins (84%; 85%) and aspirin (83%; 77%).Conclusions: BP and cholesterol are better controlled among patients in a primary healthcare system with a strong infrastructure supporting computerisation and rewarding measured performance, but this is not associated with healthier lifestyle or better quality of life. Further exploration of differences in professionals' and patients' engagement in secondary prevention in different healthcare systems is needed.