Cardiac syndrome X in Ireland: incidence and phenotype

Background Cardiac syndrome X (CSX) is typical angina pectoris with objective signs of myocardial ischaemia despite a normal coronary angiogram and may be due to microvascular dysfunction. The incidence of CSX has not been greatly investigated worldwide and its incidence in Ireland is unknown. Aims We aimed to determine the incidence of CSX in Cork University Hospital (CUH) and to establish the phenotype of the typical Irish CSX patient. Methods All patients undergoing coronary angiography in CUH during regular working hours over a 3-month period were investigated. CSX was diagnosed using standard criteria. An extended recruitment period of 14 months allowed enrolment of a sufficient number of CSX patients to enable phenotyping. Results Only 5 of 372 (1.3 %) patients undergoing angiography to investigate chest pain met the diagnostic criteria for CSX. None were given a discharge diagnosis of CSX or received cardiology follow-up. Irish CSX patients were predominantly female (88 %) with a mean age of 59.2 ± 6.6 years. Although they were significantly less functionally limited than patients with obstructive CAD, they had an equally substantial impairment in quality of life. Conclusions CSX is relatively uncommon in Ireland and is most frequently seen in middle-aged women with hyperlipidaemia. It has significant impacts on patients’ quality of life. None of the CSX patients were diagnosed as such, highlighting the lack of awareness or acceptance of this condition in Ireland. These patients require diagnosis and active cardiology follow-up to effectively manage their symptoms.