Obstetrics - Pregnancy Flashcards
Percentage of pregnancies with cardiac disease
0.2 to 4%
Types of cardiac disease that cause of maternal death
Sudden Adult Death Syndrome (31%)
Ischaemia 22%
Cardiomyopathy 18%
Dissection 14%
Valves 7%
Essential Hypertension 4%
Other 5%
Are patients who die in pregnancy usual known to have cardiac disease?
No - on 17% had pre-exisiting cardiac disease
Cardiovascular changes in pregnancy
Blood volume rises by 50%
Red cell mass rises but more slowly (dilution all anaemia)
CO increases by 50% (increased SV, in HR in 3rd tri)
SVR and BP falls in first trimester, rising to term
Factors that increase CO/DO2 etc during labour
Anxiety, pain, contractions
Post delivery - increased intra cardiac pressure as caval pressure released (auto transfusion)
WHO Risk Classification for cardiac disease in pregnancy
Classes 1 to 4
Low, medium, high
Class 4 - DO NOT GET PREGNANT
European Society Class 1 (modified WHO)
No detectable increase in mortality
Uncomplicated: pulmonary stenosis PDA MV prolapse
Successfully repaired lesions (ASD, VSD, PDA)
Isolated ectopic
European society class 2
Small increase in mortality
Operated ASD/VSD
Repaired TOF
Arrhythmia
European Society Class 2-3
Mild LV impairment
HOCM
Marfans without dilatation
ESC Class 3
SIgnificant risk of severe mortality
Mechanical valve
Fontan Systemic RV
Unprepared cyanotic disease
ESC Class 4
Extremely high risk of death
PAH (any cause)
LVEF <30% NYHA 3-4
Severe mitral stenosis
Aortic root >45mm
Antenatal approach
Joint cardiac, obs and anaesthetic clinic
Routine antenatal appts
Deliver at 32-34/40
Plan for VTE
Intrapartum principles
Have appropriate cardiology support
Aim vaginal delivery (less fluid shifts, less thrombosis)
Planned CS if condition worsening
Goals:
Reduce CVS stress
- early epidural
- Limit the length of the second stage
- Consider ECG, IABP and CVP monitoring
Problems is mitral disease and management
Stenosis is poorly tolerated
Risk of pulmonary oedema, AF (LA enlarges)
Tx- Anticoag (high risk of thrombus) Dieretics Beta block - sinus rhythm
Delivery - IABP, treat drops in SVR with vasoconstrictors/volume
Problems and management with aortic disease
Do not tolerate blood loss, tachycardia or caval compression
Avoid fluid depletion
Strict BP control in dissection (B-blockers, methyldopa)
Serial echos (use valve areas and not flows, altered in pregnancy)
Issues with the fontan circ
Palliates a singles ventricle circulation that cannot be repaired into two ventricle circ.
Decompensation - arrhythmia, failure, chest pain, hypoxia
Maintain pre-load and forward flow through pulmonary vessels
Issues with IHD in pregnancy
3-4x risk of MI in pregnancy
Mortality 45%
Look out for any patient with chest pain
DD - aortic dissection, PE
Treat as per non-preg: Angio + PCI
Aspirin, clopoidogrel and b blockers safe in pregnancy
Commonest cause of MI post parturition
Coronary artery dissection 80% of pts have no risk factors
Use of ergometrine - RISK OF CORONARY VASOSPASM
Considerations in ventricular dysfunction
May be unmasked by pregnancy
Pricipitates a peripartum cardiomyopathy
Tx: In failure:
Bed rest
Dieuretics
Anti coag
Early delivery
Inotropic support (This may be a bridge to transplant)
Peripartum Cardiomyopathy definition:
Rare idiopathic heart failure that presents in the last month of pregnancy
OR
Within 5 months of delivery.
Diagnosis of exclusion
LVEF almost always <45%
Risk factors for peripartum cardiomyopathy
Multip
Twins
Extremes of age
Symptoms of peripartum cardiomyopathy
SOB
Peripheral oedema
Fatigue
May mimiic normal pregnancy or pre-eclampsia
Treatment of peri-partum cardiomyopathy
Salt restriction
Dieurtetics
Beta blockers
Peripheral vasodilator
Risk of thrombotic complications
If in shock - IABP ECMO ?Bromocriptine
