Following a period as a locum Consultant in Monklands Hospital, Lanarkshire, he was appointed as a Consultant in Cardiovascular & General Medicine at the Ayr Hospital, South Ayrshire in 2007. Dr McGowan also holds an Honorary Consultant Interventional Cardiologist post at Hairmyres Hospital, Lanarkshire. In his NHS practice, he currently undertakes over 300 cardiac catheterisation procedures annually, half of which are coronary intervention.
He is one of eight interventional consultants based at Hairmyres Hospital delivering the Optimal Reperfusion Service to the population of Lanarkshire, Ayrshire and South Glasgow. He holds adult accreditation with the British Society of Echocardiography and undertakes transoesophageal studies. Together with two other consultants in Ayrshire he implants around 200 pacemakers annually including implantable cardioverter defibrillators. He has also maintained a strong clinical interest in the management heart failure and lead the local Heart Failure MCN.
He is a member of the West of Scotland Cardiovascular and Metabolic Research Group.