The European Association of Percutaneous Cardiovascular Interventions (EAPCI) has published a consensus document on ischaemia with non-obstructive coronary arteries (INOCA), offering guidance on the diagnostic approach and management. Published simultaneously in European Heart Journal and EuroIntervention by a task force chaired by Vijay Kunadian (Translational and Clinical Research Institute, Newcastle University and Freeman Hospital, Newcastle upon Tyne NHS Foundation Trust, Newcastle upon Tyne, UK) and co-chaired by Alaide Chieffo (IRCCS San Raffaele Scientific Institute, Milan, Italy), it offers the views of an expert panel based on existing evidence from research and best available clinical practice, and notes gaps in knowledge and potential areas for further investigation.
The authors contend that “having a universal definition of INOCA and identifying gaps in knowledge will serve to encourage research to improve outcomes for this patient population”, and note: “INOCA patients present with a wide spectrum of symptoms and signs that are often misdiagnosed as non-cardiac, leading to underdiagnosis/investigation and under-treatment. INOCA can result from heterogeneous mechanisms, including coronary vasospasm and microvascular dysfunction and is not a benign condition. Compared to asymptomatic individuals, INOCA is associated with increased incidence of cardiovascular events, repeated hospital admissions, as well as impaired quality of life and associated increased health care costs.”
On clinical presentation, Kunadian and colleagues point out: “It is important to recognise that there is gender variation in the clinical manifestation of both obstructive and non-obstructive coronary artery disease (CAD). These differences in presentation are of particular relevance in young and middle-aged women and also men who do not present with classical anginal symptoms. With the same symptoms, women are much less likely to have obstructive CAD. Importantly, INOCA is associated with a wide variation in clinical presentation and symptom burden may vary over time. These symptoms should not be automatically classified as non-cardiac in origin, particularly given the fact that women have a much higher prevalence of INOCA than men.”
The document’s key messages are that a large proportion of patients undergoing coronary angiography because of angina and evidence of myocardial ischaemia do not have obstructive coronary arteries but have demonstrable ischaemia, defined as INOCA. It says non-invasive functional techniques—exercise treadmill test (ETT), transthoracic Doppler echocardiography (TTDE), myocardial contrast echocardiography (MCE), single photo emission computerised tomography (SPECT), magnetic resonance imaging (MRI), and positron emission tomography (PET)—are options to detect ischaemia in INOCA, and that invasive strategies using coronary angiography and interventional diagnostic procedures should be implemented to differentiate between vasospastic angina, microvascular angina, and non-cardiac pain. In addition, a stratified approach to the management of INOCA to address the short- and long-term well-being and prognosis is warranted and, given the lack of in-depth knowledge, further research is urgently needed to increase mechanistic understanding and to develop innovative therapies to better manage the condition.
Among the recommendations the paper makes are that INOCA should be recognised as a clinically important entity in daily clinical practice; a systematic approach to diagnose and treat these patients should be implemented by clinicians and interventional cardiologists dealing with these patients; national and international scientific societies, as well as the pharmaceutical and biomedical industries, need to support future research to address the incomplete understanding of the pathophysiology, the lack of targeted pharmacological treatment, and the evidence-based management of patients with INOCA; and awareness of this condition needs to be created through campaigns and media to ensure timely provision of care to patients.
The consensus document was put together in collaboration with the European Society of Cardiology Working Group on Coronary Pathophysiology & Microcirculation and endorsed by COVADIS (Coronary Vasomotor Disorders International Study) group, and was proposed by the EAPCI Women’s Committee and its members.
Kunadian emphasised to Cardiovascular News that “thus far patients, in particular women, with non-obstructive coronary arteries have perhaps been told ‘they have nothing wrong with them’ despite the fact they continue to have symptoms. We hope that our document will raise the much needed awareness of this condition both among patients and the treating clinicians so that these patients will now receive the right care. This is important given INOCA is not a benign condition, it is indeed associated with adverse outcomes for our patients”.