Dr Constantinos O’Mahony

Dr Constantinos (Costas) O’Mahony

Consultant Cardiologist

QualificationsBSc (Hons), MBBS (Lond), FRCP (UK), MD (Res)

Main NHS base:

  • St Bartholomew’s & Whipps Cross Hospitals

GMC number:


Clinical interests:

Dr O’Mahony has expertise in the prevention, diagnosis and treatment of heart disease. He consults in all areas of adult cardiology, with a special interest in coronary artery disease and cardiomyopathy (heart muscle disease).

Patients with symptoms of chest pain (angina), shortness of breath, ankle swelling, palpitation, dizzy spells or fainting are evaluated, and investigations are promptly organised to allow accurate diagnosis and treatment.

Individuals without symptoms who are risk of developing heart problems in the future (e.g. those with diabetes, high blood pressure, high cholesterol, close relatives with heart disease) are assessed and provided with a personalised management plan to reduce risk and improve long term health. Those with relatives suffering from cardiomyopathy (dilated, hypertrophic, restrictive or arrhythmogenic) are screened to determine if they are affected.

A clinic consultation is typically followed by investigations to gain a better understanding of the problem. Common first-line, non-invasive investigations include blood tests, ECG (electrocardiogram), Echocardiogram (cardiac ultrasound), 24 hour Holter (ECG monitor), 24 hour blood pressure monitor, CT coronary angiogram and cardiac MRI. If required, invasive procedures (e.g. right and left heart catheterisation, coronary angiography) are undertaken and treatment with percutaneous coronary intervention (stents) delivered.

Training and Background

Dr O’Mahony is a Consultant Cardiologist based at St Bartholomew’s Hospital (Centre for Inherited Cardiovascular Disease Unit and Department of Interventional Cardiology) and Whipps Cross Hospital (General Cardiology).

He studied medicine at Imperial College London and graduated with a first class BSc (Hons) in Immunology in 1998 and with distinction in Medicine in 2001. He is a Fellow of the Royal College of Physicians. Dr O’Mahony conducts a specialist cardiomyopathy clinic and general cardiology clinic. He performs invasive haemodynamic assessments, cardiac biopsies, alcohol septal ablation and percutaneous coronary intervention.

Dr O’Mahony was awarded an MD (Res) by University College London for research into sudden cardiac death in hypertrophic cardiomyopathy (HCM). He contributed to the 2014 European Society of Cardiology (ESC) guidelines on the diagnosis and management of HCM and the development of a risk prediction model for sudden cardiac death (HCM Risk-SCD). He is an honorary associate professor at the Institute of Cardiovascular Science at University College London and his current research is focused on clinical outcomes in cardiomyopathies and novel treatments. He frequently lectures to national and international meetings.

Member of:

European Association of Percutaneous Coronary Intervention, British Cardiovascular Intervention Society, Association for Inherited Cardiac Conditions (UK), European Society of Cardiology Working Group on Myocardial diseases, European Society of Cardiology.

Clinic Times

Please note these are regular clinics, other times may be available by appointment

Mon Tue Wed Thu Fri Sat

Schedule Key

M: Monthly sessions       A: Consulting alternative weeks       A/H: Ad Hoc

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020 8936 1201
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