What is already known on this topic

• There is an increasing awareness of the prevalence of ischaemia with non-obstructive coronary arteries (INOCA) and ongoing work to improve its diagnosis. However, very little is known about the lived experience of people with these conditions, and therefore, how they could or should be supported.

What this study adds

• This study provides a richer understanding of the lived experiences of people with INOCA. It highlights the significant impact on quality of life and challenges associated with everyday living and navigating the healthcare system. It illustrates an urgent need to improve awareness, treatment and support.

How this study might affect research, practice or policy

• The study provides a rationale for improvements in education and training for first-line staff including paramedics, accident and emergency and cardiology professionals to improve the experiences of people with INOCA who present with acute symptoms. It highlights the value of shared decision-making and multidisciplinary care for people living with INOCA and the importance of involving people with lived experience in the design and delivery of care pathways and support.

Background

Coronary artery disease is traditionally characterised by obstructive atherosclerosis. However, up to two in five people experience symptoms of myocardial ischaemia without obstructive coronary artery disease. This condition can be caused by a range of underlying pathologies including coronary endothelial dysfunction, microvascular remodelling, microvascular and epicardial spasm and vasomotor abnormalities. A range of medical terms is used to describe distinct aspects of these conditions, including microvascular angina, coronary microvascular dysfunction, vasospastic angina, coronary vasospasms, coronary artery spasms, prinzmetal/variant angina and angina/ischaemia with no obstructive coronary arteries (ANOCA/INOCA). Women are disproportionately affected, particularly over the age of 40 years.

While the prevalence of INOCA is increasingly described, the nature of this condition is not. To date, the primary focus has been to develop a diagnostic consensus. However, the relationships between symptoms, mechanisms, diagnosis and treatment responses are incompletely understood.

Increasing investment in understanding diagnosis and treatment is a welcome development given the significant implications for the health and well-being of those affected. Self-reported survey data highlight a substantial adverse impact on quality of life including physical, social and mental health. However, there is a paucity of qualitative evidence about patients’ experiences of living with these conditions. This is important for understanding what is needed to improve support, long-term management of the condition and to optimise quality of life. This study investigated the lived experience of people with INOCA to gather qualitative evidence which will later inform the design and implementation of care pathways and surrounding support.

Aims

We carried out a qualitative investigation to (1) explore the lived experiences and (2) understand the support and rehabilitation needs of people living with a confirmed or presumed diagnosis of INOCA. Our analysis generated two sets of themes which are presented in two separate manuscripts. This manuscript presents findings relating to the first aim, that is, peoples’ lived experiences of INOCA conditions.

Methods

Interviews were conducted with English-speaking adults aged >18 years who self-identified as having INOCA. This was defined as microvascular angina, coronary microvascular dysfunction/disease, vasospastic angina, coronary vasospasms, coronary artery spasms, prinzmetal or variant angina, ANOCA/INOCA. Considering previous research detailing the challenges of diagnosis and advice from a patient with lived experience of INOCA, we did not ask participants to provide objective evidence of a definitive diagnosis but to self-identify based on their current medical advice. Information about the study was shared by patient representatives via online patient support groups, personal social media accounts and included in a British Heart Foundation ‘Heart Voices’ newsletter.

People expressing an interest in the study were provided with details about the research and invited to an informal telephone discussion with the interviewer (HH) to discuss the research aims and procedures. Those wishing to proceed completed a written consent form returned via email or post prior to interview. Recruitment ceased after interviewing 17 participants, when thematic saturation was reached.

Patient and public involvement

Study materials including the protocol, participant information sheet and consent forms and interview guides were developed under the guidance of a person with lived experience of INOCA. Discussions highlighted the importance of monitoring participants for signs of stress caused by the interview and ensuring that participation did not trigger chest pain. This prompted the inclusion of a specific distress protocol to guide the interviewer. Other improvements included the refinement of language to ensure that a range of terms used by patients to describe their condition were included.

Interview procedures

An interview guide taking the form of a workbook (online supplemental material 1) was sent to participants prior to their interview. This provided participants with space to reflect and make notes on their lived experience prior to the interview, although it was stressed that doing so was entirely optional. The workbook included broad open questions about current health concerns and the impact of INOCA symptoms and/or diagnosis. It was followed by more specific questions about managing lifestyle, medications and psychological health. The workbook was subsequently used as a semistructured interview guide.

Interviews were conducted via Zoom or Microsoft Teams, with three interviews carried out by telephone to suit participants’ preferences or connectivity requirements. All interviews were conducted by HH, an experienced female qualitative psychology researcher. Interviews were audiorecorded and limited to a maximum of 1 hour to limit cognitive or emotional burden for participants.

Data analysis

Recordings were transcribed verbatim by a professional transcription service. Transcripts were sent to participants for review; one participant responded with minor clarifications which were included in our analysis.

Reflexive thematic analysis with inductive, semantic coding was used to analyse the data. Consistent with recommendations, we did not set out to achieve intercoder reliability. Instead, two researchers coded the transcripts separately to encourage reflexivity and ensure our analysis considered different possible interpretations. Two researchers (HH and DP, both with postgraduate psychology qualifications and experience in qualitative analysis) reviewed 50% of the transcripts each. DP and HH independently developed preliminary coding frameworks presenting initial themes, which they compared, merged and refined. Further discussion with a third researcher (AC) supported the sense-checking of candidate themes. Preliminary themes were also shared with all interview participants at this point, who were encouraged to feed back any questions or views. Four participants responded, advising that the themes presented gave a fair reflection of their experiences. Final themes are presented below along with illustrative participant quotes.