Cardiac syndrome X in Ireland: incidence and phenotype
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.
We aimed to determine the incidence of CSX in Cork University Hospital (CUH) and to establish the phenotype of the typical Irish CSX patient.
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.
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.
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.
KeywordsAngina pectoris Normal coronary arteries Microvascular angina Epidemiology
JD is in receipt of an academic training fellowship award from the Health Research Board, an agency sponsored by the Irish government. The authors are supported, in part, by Science Foundation Ireland in the form of a centre grant (Alimentary Pharmabiotic Centre) under Grant Number SFI/12/RC/2273.
Compliance with ethical standards
This study was not directly funded. The main author, JD, is in receipt of a government sponsored academic research training award.
Conflict of interest
The authors report no conflicts of interest in this case.
The study was approved by the clinical research ethics committee for the Cork teaching hospitals and complied with the 1964 declaration of Helsinki and its later amendments and all participants gave full informed consent.