Microcirculation in Ischaemic and Non-Ischaemic Heart Disease

2018 Health Professional Scholarship

Years funded: 2019-2021

The proposed projects examine two contentious topics in cardiology, reperfusion injury and
chest pain syndromes. The first project will focus on utilising doxycycline, a commonly
used antibiotic, to reduce the damage caused by heart attacks. The second project will
investigate chest pain in patients without obstructive coronary disease measuring
resistance in the small vessels of the heart.

The modern treatment of heart attacks with urgent angioplasty and stents aims to save as
much heart muscle as possible by restoring blood flow to the heart when the coronary
artery becomes occluded. Despite rapidly restoring blood flow, heart muscle cells can
continue to die once blood flow is restored due to the toxicity of the oxygen molecules and
waste products on the injured cells (so-called reperfusion injury). Project 1 is a randomised,
placebo-controlled study investigating the effect of doxycycline on reducing heart muscle
injury when given before opening the occluded artery. Doxycycline has numerous beneficial
effects that might make it a useful, cost-effective additional therapy for heart attacks.

Chest pain is a common symptom among patients who often do not have evidence of
significant coronary disease. This chest pain conundrum could be related to abnormalities
in blood flow in the small vessels of the heart muscle. In Project 2, we will utilise an
invasive measure of small blood vessel function (the index of microcirculatory resistance)
to investigate blood flow changes.