Cardiac ischemia due to physical or mental stress in women with suspected coronary microvascular dysfunction (CMD)

Coronary microvascular dysfunction (CMD) is now acknowledged as a distinct type
of ischemic heart disease. Numerous patients, particularly middle aged women,
suffer from this chronic, disabling disorder. Unfortunately, the diagnosis is
still often missed leading to unnecessary health care utilization with
associated costs, diminished quality of life, reduced work participation and,
last but not least, a worse cardiovascular prognosis. Several reasons play a
role in the under-diagnosis of CMD. Firstly, symptoms are not that typical for
angina. They can occur at varying levels of exertion, not during, but after
exertion, at rest, or at mental stress. The simplest clue to CMD is to
demonstrate cardiac ischemia in the absence of obstructive CAD. Unfortunately,
standard ischemia detection tests like an exercise ECG do not perform well in
patients with CMD. One possible explanation is that ischemia occurs not during
but after the exertion. Another issue is that CMD patients often have symptoms
after mental stress which is usually not mimicked in a clinical setting.
Our hypothesis is that 24 hour holter monitoring after physical or mental
stress testing can enhance ischemia detection in CMD patients. We thus expect
it to facilitate more widespread diagnosis of MCD and prevent a substantial
part of patients from having to undergo a more costly and burdensome functional
test.

to facilitate diagnosis of CMD with the detection of ischemia after stress with
24 hour holter monitoring

cross-sectional cross-over study

The physical and mental stress tests are both stress tests which can be
compared with the stress in daily life. During each stress test, participants
will get a venous infusion needle and have collect several cortisol
measurements with cotton swabs. The Holter monitor, which they have to wear for
24 hours, is small, and comes with a comfortable thin-wire *Leadform* cable
that makes monitoring with 10 electrodes practical and without hindering normal
daily functioning.The risk of serious adverse events is extremely low, as
explained in section 9.2.2. The benefit of the availability of a more facile
way to diagnose CMD is substantial. The only way to enhance identification of
patients with CMD and distinguish those at increased cardiovascular risk who
might benefit from medical therapy, is to enable widespread diagnosis by
relatively easy and save tests to detect CMD in daily clinical practice. These
tests are not only essential for widespread diagnosis, but also crucial to
evaluate novel treatment options.