Mitral stenosis

Question 1

Outline specific history and examination findings you would elicit in a woman with or suspected of having mitral stenosis:

Answer 1

History:

• When was she diagnosed and how
• When was last ECHO and result
• Treatments including medications, surgery and compliance.
• Who is her cardiologist; does she get regular follow-up
• Functional status: SOB at rest and exertion; exercise tolerance; palpitations; orthopnoea; paroxysmal nocturnal dyspnoea.
• Concerning symptoms: pink frothy sputum, chest pain with exertion, progressive orthopnoea, PND.
• FamHx: heart disease, sudden cardiac death.

Exam findings:

• Observations particularly HR and BP.
• WOB, evidence of cyanosis
• Chest
• Heart
• Peripheral oedema

Question 2

Outline important baseline investigations to perform preconceptually or at booking in addition to usual investigations:

Answer 2

• ECG
• CXR
• ECHO
• Renal function

Question 3

Outline pre-conceptual counselling for a woman with mitral stenosis:

Answer 3

Cardiac risk to mother:

• Risk of arrhythmia: AF, flutter or SVT.
• Risk of left atrial thrombus
• Risk of congestive heart failure
• Risk of pulmonary HTN and pulmonary oedema.

Obstetric risk to mother:
- Increased risk of CS

Risk to fetus:

• FGR
• PTB
• Fetal death
• Low birthweight

Long-term effects of pregnancy/disease on heart

Modification of cardiac treatment:
- Metoprolol: slows HR and allows time for LA emptying.

Optimise cardiac status:

• Mitral valve balloon valvotomy or valve replacement prior to pregnancy if severe.
• Iron supplementation / prevent anaemia.

Thromboprophylaxis during pregnancy:
- Aspirin or clexane

Contraception

Question 4

You are seeing a pregnant woman with mitral stenosis at 32 weeks gestation; outline your plan for labour and delivery assuming no other complications arise:

Answer 4

Delivery in tertiary centre with cardiothoracic unit.

Arrhythmia:

• Telemetry
• Early epidural
• Beta-blocker e.g. metoprolol

Low CO/SV:

• IVL, FBC, G&H
• Active 3rd stage management to avoid PPH.

Risk of pulmonary oedema:

• Frusemide during 2nd stage
• Avoid carboprost and syntometrine which increase pulmonary pressure.

Postnatal:

• Breastfeeding
• Contraception
• Follow-up with cardiologist.
• Medication changes