This study evaluated the first year's experience of a large interventional centre in the UK after a primary percutaneous coronary intervention (PCI) programme that runs 24 hours a day and seven days a week was started. Workload, patient outcome, length of stay, and effect on the remainder of the interventional service were analysed. The primary PCI service for a mainly urban population of 800,000 was started in April 2005. All relevant characteristics, details of procedures, outcome, and other data on quality of care were collected and entered prospectively onto a computerised database. Data were analysed with SPSS (version 13.0). Over a 12-month period, 305 patients were diagnosed with ST elevation myocardial infarction (STEMI), of whom 259 (85%) were accepted for primary PCI. Median door-to-balloon time was 98 minutes, which decreased from 106 minutes in the first six months to 93 minutes in the second six months (p<0.005). In-hospital mortality was 4.5% and 30-day mortality was 4.9%. Median length of stay was three days, which was reduced from the six days previously reported after thrombolysis. Waiting times for other acute and elective PCI procedures did not increase after initiation of the primary PCI programme. Primary PCI can be delivered successfully in a setting in the UK with low mortality and reduced length of stay and without a negative impact on other interventional services.