The influence of the menstrual cycle on diagnostic results of cardiovascular diseases - The Cycle Study II

The menstrual cycle plays a significant role in women*s health and disease.
Exacerbation of various different medical conditions such as migraine,
epilepsy, asthma and rheumatoid arthritis at specific menstrual cycle phases is
a well-recognized phenomenon (1).
However the knowledge about menstrual cycle-related cardiovascular disease is
scarce. This is remarkable because other forms of cyclicity such as diurnal and
seasonal patterns have been linked to the occurrence of many cardiac symptoms
such as several arrhythmias including paroxysmal tachycardia and atrial
fibrillation (2, 3). Although case series and case reports have implicated a
relationship between cardiac symptoms and the menstrual period (4-6) no
systematic research has been performed on this topic and the association
between specific phases of the menstrual cycle and cardiac complains is not
routinely examined by health care professionals.
Moreover, previous research has shown that plasma lipids and lipoproteins in
healthy regularly menstruating women are lower in the luteal phase compared to
the follicular phase(7). These changing lipid levels could cause under or
overtreatment of women on lipid lowering therapy when lipid levels are only
measured in one menstrual phase. However, until now these cyclic lipid
fluctuations have not yet been determined in women with hyperlipidemia.

To investigate whether the menstrual cycle influences diagnostics in patients
with cardiovascular disease

We will perform three pilot studies.
Pilot study 1: 32 women with diagnosed arrhythmia(s) with a regular menstrual
cycle.
Pilot study 2: 221 women who are performing an exercise test for medical
reasons.
Pilot study 3: 71 women with familial hypercholesterolemia and 71 healthy
controls.
The goal is to investigate whether the menstrual cycle influences diagnostic
results in cardiac symptoms and lipids.


1.Participants are eligible if they have diagnosed arrhythmia(s) ) and have a
regular menstrual cycle (21-35 days).
2.Participants are eligible if they are performing an exercise test for medical
reasons in the Erasmus MC and have a regular menstrual cycle (21-35 days)
3.Participants are eligible if they are diagnosed with either heterozygous or
homozygous FH based on DNA tests or according to the Dutch Lipid Network
Criteria.


Menstrual phase will be determined by asking the participants to report their
first day of vaginal bleeding of their last menstruation to the investigators
and will be confirmed by female hormone blood levels 4 times in the menstrual
cycle. For study 2, blood samples will be collected one-time only at the same
day of the exercise test.
For study 1, blood samples will be collected with at-home finger prick
self-tests and for study 3 with venapunctions. The participants are asked to
perform the finger prick self-test/venapunction four times in one menstrual
cycle:
- the follicular phase (day 3-5)
- during ovulation* (around day 14)
- the luteal phase: mid-luteal (8 days after ovulation) and late-luteal (2 days
before expected menstruation)
* determined by the participant to which we provide self-administrable tools to
estimate ovulation

Interventions:
Pilot study 1: participants will be connected to the AEM for ±4 weeks (1
menstrual cycle). They will keep an electronic diary to report their symptoms
of palpitations. Blood will be collected four times with finger prick
self-tests to determine the endogenous female hormone levels. A short digital
survey on intake of specific food/drinks/drugs survey will be send on the same
days as their finger prick self-tests and they will be asked to weigh
themselves that morning.
Pilot study 2: One-time only blood collection (4 EDTA tubes of 7 mL) to
determine endogenous female hormone levels and lipids.
Pilot study 3: Blood lipid levels will be determined with venapunction in the
participants in 4 different phases of the menstrual cycle. On the same day as
the finger prick self-tests, the participants will receive 24 hour recall
dietary survey Compl-eat and are asked to report their weight in the morning of
that day.

The AEM connection, replacement and removal will take place at the Vascular
medicine outpatient clinic of the Erasmus MC. Blood samples from pilot study 2
will be collected at the central place for blood collection of the Erasmus MC.
Finger prick self-tests for pilot study 1 and 3 will be carried out at home.

Inclusion will start after METC approval of the study protocol. The total
duration of the study is expected to be 1 year.

1. Patients with palpitations (appendix 1a)
Step 1: Arrhythmia diagnostics and symptoms
AEM
The AEM will be connected to the participating woman at the Vascular Medicine
outpatient clinic in the Erasmus MC. After two weeks, the AEM will be
disconnected and a new one will be connected. This will be repeated during
until two menstrual cycles of the women have passed.

Diary
All subjective experiences of palpitations will be recorded with an electronic
diary during the time of AEM connection.

Step 2: Blood sampling
Blood samples required
4 EDTA tubes (7 mL, plasma)
- 2 to confirm menstrual phase (LH, FSH, estrogen and progesterone)
- 2 for lipid profile (TC, LDL-C, HDL-C, TG, apoB and Lp(a))

Assessing the menstrual phase:
Blood samples of will be collected three times per menstrual cycle to measure
levels of LH, FSH, estrogen and progesterone.

Timing:
- First blood sample: 3 to 5 days after start of the menstruation (menstruation
or early follicular phase).

- Second blood sample: directly during (same day or day after) the LH-peak
(determined by the patient by a self-administrable tool to estimate ovulation).

- Third blood sample: 21 to 28 days after the first day of menstruation (luteal
phase).



When the patient uses the contraceptive pill:
- First blood sample: at the first day of a new pack with instructions to take
the first pill after blood is drawn.

- Second blood sample: around day 10 of the pack.

- Third blood sample: around day 21 of the pack


2. Patients with chest pain
Step 1: Cardiac ischemia diagnostics and symptoms
Symptom limited exercise testing
The symptom limited exercise testing will be performed at the same days as the
blood sample collections (same as in palpitations population).

Step 2: Blood sampling
Same as in palpitations population.

3. Patients with FH
Blood sampling
Same as in palpitations population.

4. Controls
Step 1: Cardiac ischemia/arrhythmia diagnostics and symptoms
Same as in palpitations/chest pain population

Step 2: Blood sampling
Same as in palpitations population.

We expect a minimim burden and a negligible risk for the participators.