Background and aim: It is recommended that medicines for the secondary prevention of coronary heart disease (CHD) are prescribed to patients after coronary intervention and healthcare professionals should support patients to take these medicines, usually for the rest of their life. This study aimed to explore patients’ adherence to secondary prevention medication after elective percutaneous coronary intervention (PCI).

Methods: This mixed methods study used an explanatory, sequential design. In phase one quantitative data were collected from a convenience sample (n=93) approximately three months after elective PCI using a validated self-administered survey tool. Quantitative data were subject to univariate and bivariate analysis. Phase one findings were used to purposively select ten participants from the original sample for interview in phase two of the study. Thematic analysis was used to analyse qualitative data.

Results: Participants had a mean age of 66.25 years (SE±10.56), were mostly male (n=70/75.3%) and Caucasian (n=80/86%). After PCI, 91.4% (n=85) of participants reported that they took their medications as prescribed and were confident that they knew how to take them. Further exploration though revealed that non-adherence was an issue and this was categorised as either unintentional or intentional. Participants often did not know why they were taking the medicines. Many perceived medication to be of little benefit or even detrimental to health.

Conclusion: Adherence to secondary prevention medicines after elective PCI is sub-optimal. A co-production model should be used to encourage, educate and support patients’ adherence to medicines to reduce their risk of CHD progression.