Obstetric cardiology COPY Flashcards
How do the following change in pregnancy:
- blood volume
- cardiac output
- stroke volume
- blood volume -> increase 35%
- cardiac output -> increase 40%
- stroke volume -> increase 30%
How do the following change in pregnancy:
- heart rate
- systemic vascular resistance
- mean arterial pressure
- heart rate -> increases 15%
- systemic vascular resistance -> decreases 15-20%
- mean arterial pressure -> no significant change
How do the following change in pregnancy:
- systolic BP
- diastolic BP
- Central venous pressure
- systolic BP -> decreases 3-5 mmHg
- diastolic BP -> decreases 5-10 mmHg
- Central venous pressure -> no significant change
How do the following change in the pregnancy:
- serum colloid osmotic pressure
- haemoglobin
- serum colloid osmotic pressure -> decreases 14%
- haemoglobin -> decreases 2%
Why does a pregnant woman may seem to be anaemic?
Drop in serum colloid osmotic pressure (due to vasodilatation) -> drop in haemoglobin -> pregnant women may therefore seem to be anaemic
- Define hypertension in the pregnancy
- how many times do you need to measure and when to establish the diagnosis of hypertension?
Hypertension is still defined as 140/90 taken on two separate occasions and at least 4 hours apart
What may be a characteristic and why of ‘booking BP’ in the first trimester of pregnancy?
Booking BP -> at the beginning of pregnancy may be ‘artificially’ low due to peripheral vasodilatation (therefore it’s not unusual to see BPs of 90/60) - normal in 1st trimester of pregnancy
What are the three types of hypertension in pregnancy?
Three types of hypertension in pregnancy:
A. Hypertension BEFORE pregnancy (chronic hypertension)
B. Hypertension that develops DURING pregnancy with NO proteinuria (gestational
hypertension)
C. Hypertension that develops DURING pregnancy with proteinuria (pre-eclampsia)
What’s gestational hypertension?
- hypertension that is new and develops after 20th week of pregnancy
- not associated with proteinuria
- normal biochemistry
- normal foetal growth
- Should gestational hypertension be treated?
- What’s the risk of gestational hypertension?
Gestational hypertension should not be treated- > antihypertensive
drugs would cross the placenta and affect foetus
- Risk of developing pre-eclampsia (30%) -> there is no way of screening who with gestational hypertension will develop it -> so need to monitor women at risk (with hypertension)
Definition of pre-eclampsia
Pre- eclampsia : Hypertension + proteinuria arising after 20th week of gestation
What are possible complications for babies surviving maternal pre-eclampsia?
risk of long-term complications of:
- intrauterine hypoxia
- pre-maturity,
- heart disease
- diabetes
What are the elements of ‘moderate risk’ of pre-eclampsia?
Moderate Risk:
-nulliparity
- age >40 years old
- maternal BMI >35
- FHx of pre-eclampsia
- pregnancy interval >10 years
- multiple pregnancy
What are the elements of ‘high risk’ of pre-eclampsia?
High Risk:
- chronic hypertension (before pregnancy)
- Past Hx (HTN, pre-eclampsia, eclampsia in previous pregnancy)
- pre-existing CKD, DM, autoimmune disease (SLE, anti-phospholipid
syndrome)
Pathophysiology of pre-eclampsia
Pathology of pre-eclampsia:
• sort of graft vs host disease
- spiral artery will not become modified (high resistance, low capacity; normally there will be modifications in SM) -> spiral artery is not remodelle
- dysregulation of maternal vascular endothelial cells -> multisystem disorder
What is the classical characteristic of eclampsia?
What effects does it have on the foetus?
- eclampsia: a new onset of tonic- clonicseizurein presence ofpre-eclampsia (hypertension + proteinuria in 20 weeks gestation)
- maternal convulsion -> foetal distress and bradycardia
Signs and symptoms of eclampsia and pre-eclampsia (similar)
Signs and symptoms related to end-organ dysfunction e.g. papilloedema
- headache -> usually frontal
- hyper-reflexia
- nausea and vomiting
- generalised oedema (angioedema, peripheral) -> as endothelial injury -> capillary fluid leaks out
- RUQ pain +/- jaundice
- visual disturbance (flushing lights, blurred/ double vision)
- change in mental status
- clotting factors abnormalities -> due to vascular endothelium in the liver being destroyed
- Proteinuria -> due to endothelium being destroyed -> protein leak out
What is the pathological process behind increased BP in pre-eclampsia/eclampsia?
*hypertension is due to the fact that endothelium is broken, stops producing NO and controlling BP
Possible maternal complications of eclampsia
Materna complicationsl:
- HEELP syndrome (haemolysis, elevated liver enzymes, low platelets)
- DIC
- AKI
- Adult Respiratory Distress Syndrome,
- Cerebrovascular haemorrhage
- CNS damage
- death
Possible foetal complications of pre-eclampsia/ eclampsia
Foetal:
- IUGR -> as the placenta is hypoperfused
- pre-mature birth
- RDS
- death
- placental abruption
- excess skin - decreased adipose tissue
- ‘head sparing effect’ - head is larger than other parts of the body - as all of the limited nutrient and oxygen are driven there in order to preserve
brain
-small body
Differentials for eclampsia
Differentials: hypoglycaemia, pre-existing epilepsy, head injury, hemorrhagic stroke, meningitis, medication-induced, brain tumour, cerebral aneurysm, septic shock, ischaemic stroke
Investigations and rationale in eclampsia
- FBC -> decreased Hb, decreased platelets
- U&Es -> assess for kidney damage (elevated: urea, creatinine) and decreased urine output
- Clotting studies
- Blood glucose
- Abdominal USS -> to role out placental abruption
- CTG monitoring -> foetal distress and bradycardia
Management of eclampsia
Management:
-
Resuscitation
- ABCDE
- patient should lie on L lateral position, secured airway and oxygen therapy
- Fluid restriction (max 80ml per hour) -> as we want to avoid pulmonary oedema *even if renal failure -> as pulmonary oedema is more likely to kill -
Cessation of Seizures
- Magnesium sulphate (we do not know how it works, but it does work, probably stabilises cellular membrane)
*Assess for signs of hyper-magnesia (respiratory depression, hyper-reflexia), monitor foetus by CTG
3. Control BP
- IV anti-hypertensives -> Labetalol and Hydralazine (target MAP <120 mmHg)
*labetalol is an old-fashioned drug, only used nowadays in pre-eclampsia (newer drugs may harm baby)
*rapid decrease in maternal BP -> foetal HR abnormalities -> need for continuous CTG for 30 minutes after IV anti-hypertensives
4. Delivery of baby and placenta
- to treat eclampsia definitely
*But mum must be stable before delivery - seizures controlled, severe hypertension treated and hypoxia corrected -> this all is regardless of any foetal compromise
- what’s the preferred mode of delivery in eclampsia?
- what happens to mum after delivery?
- what do we need to remember about (baby wise)
- CS is recommended mode of delivery
* after delivery, patient required HDU care until stable (well controlled BP, adequate urine output, discontinuation of magnesium sulphate -> usually minimum 24 hours)
- Post-natal follow up and monitoring are required
What is better tolerated in pregnancy: mitral regurgitation or stenosis? Why?
Regurgitation is better tolerated than stenosis -> decreased peripheral vascular resistance (in pregnancy) will reduce the degree of regurgitation
* Mitral stenosis is a problem
What’s the most frequent valvular lesion associated with Rheumatic Heart Disease?
Mitral stenosis
- Possible complications of mitral stenosis in pregnancy
- What’s the current advice on management of pregnant woman with mitral stenosis
What’s the prognosis for women with cyanotic and acyanotic CHD in terms of pregnancy?
- Women with acyanotic heart diseases -> should be OK with pregnancy
- Women with cyanotic heart disease -> poor prognosis, increased risk of
complications
What possible complications are there for a pregnant woman with CHD?
- pulmonary hypertension
- cyanosis
- severe LV outflow obstruction
*Moreover the baby will be at increased risk (2-10%) of CHD -> therefore need to monitor them closely (to have management plan to be implemented straight after delivery)
ASD in a pregnant woman - do we do anything about that?
- We tend not to close ASD while during pregnancy
- if there is significant L- R shunt or large hole we will close, as this will lead to a significant compromise in oxygen delivery to a baby and mum (as O2 demands are increased)
What do we do in VSD in pregnancy?
Endocarditis could be more common in pregnancy as there is slight immunosuppression -> give endocarditis prophylaxis
- What’s the most common CHD valve disease among pregnant women?
- what’s the prognosis for that in relation to pregnancy?
- what’s possible advice to avoid
- what to do if symptomatic
- bicuspid aortic valve -> aortic stenosis
- most will be well tolerated and asymptomatic
- Advice to avoid: lying flat. epidural. nifedipine (CCB)
- If symptomatic: bed rest, B-blocker, balloon valvotomy
Hypertrophic Cardiomyopathy
- inheritance pattern
- diagnosis
- risk
- 70% Autosomal dominant -> screen baby
- diagnosis: ECHO, symptoms, murmur
- Risks: sudden death, endstage HF, fatal CVA,
Hypertrophic cardiomyopathy in mum and pregnancy
- what’s the prognosis
- what we should avoid/ be cautious about
- Pregnancy may exacerbate the condition -> risk of severe and rapid HF or even death of mum
- avoid regional anaesthesia - as vasodilation is poorly tolerated
What’s prognosis for the pregnancy in women with cyanotic heart disease?
(women and baby wise)
- poor prognosis (due to significant R-L shunting and decreased peripheral vascular resistance)
- cyanotic HD is very poorly tolerated by the baby = IUGR
*Women who grew up with cyanotic HD may be used to low sats, but developing foetus would not be
What do we advice a woman who has Eisnmengers and becomes pregnant? Why?
EISENMENGERS -> strong advice to avoid pregnancy due to high mortality rate -> offer TOP
This is because pregnancy can exacerbate R-L shunt (due to fall in peripheral resistance) -> 40% of risk of maternal death (during delivery or 1 week post-partum) due to thromboembolism, PE, hypovolemia
When prophylaxis for bacterial endocarditis is recommended in pregnant women?
Ischaemic heart disease in pregnancy
- why is it more common?
- what’s prognosis?
- IHD in pregnant women is increasing due to increase in IVF and
maternal age -> older women get pregnant, there is therefore increase in mums with IHD
- strain on the heart during later pregnancy and delivery means poor prognosis
Possible management of Ischaemic Heart Disease in a pregnant woman
aspirin, B-blocker, Heparin, nitrates, angiography, stenting, possible thrombolysis
What’s the incidence of cardiac arrest in pregnancy?
- what’s the prognosis
- what are the possible causes
- incidence: 1 in 30, 000 women in late pregnancy
- prognosis: poor chance of maternal survival
- causes: haemorrhage, placental abruption, PE, eclampsia, drug toxicity
Management of cardiac arrest in pregnancy
- L lateral positions -> t decrease strain on vena cava
- If resuscitation not effective in 4 minutes -> Empty the uterus (delivering baby as it will release vena cava and thoracic compression , improves ventilation - does not matter what stage of gestation is it - needs to save mum’s life)
- What’s Peripartum cardiomyopathy?
- what are its risk factors?
What’s clinical presentation of Peripartum Cardiomyopathy?
Diagnostic criteria for Peripartum Cardiomyopathy
Prognosis for the outcome of Peripartum Cardiomyopathy
Cardiomyopathy in pregnancy: mixed outcomes -> 10% may die, some will get heart transplant, 60% may recover and have fairly normal heart function, 40% may never recover in terms of cardiac function
Anti-coagulant use in pregnancy
- which one are safe
- which one are not
WARFARIN not to be used in pregnancy! -> teratogenic:*chondroplasia punctata -
abnormality of bone and cartilage, optic atrophy, neurodevelopmental delay
Heparin and LMWH
- are safe for a baby as do not cross
placenta (but not as effective for mum as warfarin)
*factor Xa inhibitors (e.g. Fondaparinux, Apixaban) -> unknown safety in pregnancy (although some studies suggest they do not cross the placenta so perhaps safe)
Use of these drugs in pregnancy: recommended or not:
- antihypertensives
- B blockers
- CCBs
- ACE inhibitors and Angiotensin Receptor Blockers
- diuretics
