Introduction: There is a need to study the level of percutaneous coronary intervention (PCI) care in the UK to promote improvements in care for all patients with cardiovascular disease. The aim of this thesis was to utilise contemporary population-based data to perform a number of investigations and answer several important questions regarding the level of care provided to patients who have undergone PCI in the UK on the basis of outcomes including survival. Methods: A linked population-based study using the prospectively collected British Cardiovascular Intervention Society (BCIS) registry of patients who have undergone PCI in the UK since January 2005. Three main analyses were performed and for each part; a literature review, analysis (descriptive statistics, comparisons, adjusted associations and survival), multi-level modelling and fit for purpose imputation were conducted. Results: In the first analysis, 5,065 patients with unprotected left main stem disease (UPLMS) were studied. More than half of patients treated with PCI to the UPLMS presented acutely, their early and late mortality were significantly worse than that for elective patients. Cardiogenic shock was common in ST elevation myocardial infarction (STEMI) and associated with a 1 in 2 risk of early mortality. In acute patients, radial access was associated with improved early outcomes. In the second analysis, 10,827 patients with UPLMS were studied. The number of acute patients with UPLMS PCI increased over the years with stable early and late mortality rates. In the third analysis, 98,637 patients with STEMI were studied. The survival of primary PCI patients was worse than that of facilitated and rescue mainly because majority of the procedures were performed after more than two hours from the onset of symptoms. Old age, cardiogenic shock, more than two hours delay before intervention, inter-hospital transfer and being already in a cardiac centre were independent predictors of worse survival in primary interventions. Conclusions: The novel prospective data used in this thesis have provided the opportunity to gain more knowledge and understanding of the quality of care provided to patients following PCI which represents a step forward in the assessment and improvement of cardiovascular health services in the UK.