Diagnosis of coronary microvascular dysfunction in the clinic

The clinical importance of coronary microcirculation is still often underestimated or even neglected. Patients with angina pectoris represent a particular diagnostic challenge. The cardiologist must decide which assessments to perform regarding coronary microvascular dysfunction (CMD) depending on the clinical presentation of the patient, the co-existing comorbidities, local availability, methodical expertise and costs.
This article by P. Ong et al is interesting as it gives an overview of the available techniques for the assessment of CMD in the clinic. These techniques can be either non-invasive (e.g. transthoracic Doppler-echocardiography assessing coronary flow velocity reserve, cardiac magnetic resonance imaging, positron emission tomography) or invasive (e.g. assessment of coronary flow reserve and microvascular resistance using adenosine, microvascular coronary spasm with acetylcholine).
It is now possible to have a combined approach by an interventional diagnostic procedure (IDP) including acetylcholine provocation testing as well as assessment of CFR with adenosine using a dedicated wire.
Take-home message: In clinical practice, it is important to assess coronary microvascular function. A single diagnostic method will often not be enough to establish a diagnosis regarding CMD. The combined invasive assessment of coronary vasoconstrictor as well as vasodilator abnormalities called interventional diagnostic procedure (IDP) represents the most comprehensive coronary vasomotor assessment.