Cardiovascular disease

Question 1

Pulmonary hypertension is an increase in blood pressure by an average of …….. mmHg at rest or ……… mmHg on exercise

Answer 1

25

30

Question 2

What is the effect on the chambers of the heart in pulmonary hypertension?

Answer 2

RV failure due to increased RV afterload.
Pulmonary artery vessel narrowing leads to increased load on the right ventricle. The right ventricle will adapt by increasing muscle contractility and wall thickness. To maintain cardiac output, RV dilates and HR increases. Ultimately resulting in increase in wall stress, pushing the septum (between the R and L ventricle) to the left and impinging on the LV space. The decrease in left ventricle output leads to an increase in vasporessin/RAAS release which leads to an increase in renal sodium and water retention, therefore increasing the extracellular fluid. This increases cardiac filling pressure, resulting in RV dilation and remodelling. This leads to increase myocardial wall stress and ischemia

Question 3

What is pulmonary hypertension?

Answer 3

A constriction of the pulmonary artery (therefore reduction in the amount of deoxygenated blood that can pass to the lungs)

Question 4

What is the maternal mortality of PHT?

Answer 4

25%

Question 5

How does fixed PVR in PHTN affect the CVS of pregnant women?

Answer 5

PVR in PHTN is fixed (compared to decreased as normally seen in pregnancy) and therefore women are unable to increase pulmonary blood flood to meet the demands of increased CO

Question 6

What advice should be given to women with PHTN in pregnancy?

Answer 6

Avoid pregnancy
if pregnant, consider TOP
if ongoing pregnancy, advise the following:
- limit activity
- avoid supine position
- symptomatic treatment with o2, diuretics, vasodilators (sildenefil)

Question 7

What advice should be given to women with PHTN intrapartum?

Answer 7

avoid hypotension

maintain preload

Question 8

What advice should be given to women with PHTN postpartum?

Answer 8

avoid blood loss, thromboprophylaxis

Question 9

What effect does patent ductus arteriosis have on the heart?

Answer 9

Patent ductus arteriosis is a connection between the aorta and the pulmonary artery that has failed to close at birth. It means blood from the aorta can flow back into the pulmonary artery and therefore lead to LV hypertrophy, LV failure, MR

Question 10

What effect does patent ductus arteriosis have in pregnancy?

Answer 10

• Corrected patent ductus arteriosis poses no threat and does not need prophylaxtic abx.
• Uncorrected also poses little risk but increased chance of CCF

Question 11

What is the most common congential heart defect in women?

Answer 11

Atrial septal defect

Question 12

What are the risks associated with pregnancy in women with atrial septal defect?

Answer 12

Low risk condition in pregnancy, usually well tolerated. However, risks may include

• migraine
• paradoxical embolism (low risk)
• hypotension post PPH due to increased left-to-right shunt (drop in LV output and therefore coronary outflow)
• supraventricular tachycardia (very low risk in women under age of 40)

Question 13

what is a paradoximal embolism?

Answer 13

A clot passing from venous to artery. Usually the result of an atrial septal defect, which eventually travel to the lungs causing a pulmonary embolism.

Question 14

What effect does ventricular septal defect have in pregnancy?

Answer 14

Increased volume load of LV

Usually well tolerated in pregnancy unless associated with Eisenmengers syndrome

Question 15

What pressure gradient values defines congential aortic stenosis?

Answer 15

Significant obstruction will result if the valve area is <1cm3 or if the mean gradient is severe (>50mmHg in the non pregnant state)

Note: the gradient will increase as the CO increases in pregnancy, this is not an indication that the stenosis is increasing. If there is no change in gradient, this is cause for concern as the LV may be decompensating.

Question 16

What are the risks of moderate to severe congenital aortic stenosis in the pregnant woman?

Answer 16

angina, hypertension, CCF and sudden death.

This is because there is limited ability to increase CO during pregnancy secondary to the stenosis.

Question 17

How would you treat congential aortic stenosis in the pregnancy women?

Answer 17

If the LV function is good, severe aortic stenosis can be treated with B blockers.

Question 18

Where is the most common anatomical position where coarctation of the aorta affects?

Answer 18

Descending aorta, distal to the origin of the subclavian artery

Question 19

What are the risks of UNcorrected coarctation of the aorta?

Answer 19

Mild - HTN and CCF

severe - aortic rupture and dissection

Question 20

How can you reduce the risk of severe complications assocated with uncorrected coarctation of the aorta?

Answer 20

BP control and B blockers to decrease cardiac contractility.
Consider an MRI pre-pregnancy to diagnose any aneurysm (or post stenotic dilation around the site of repair if there has been a correction)

Question 21

What is the genetic link in marfans syndrome?

Answer 21

Autosomal dominant condition caused by a defect in the fibrillin 1 gene

Question 22

What are the common associated cardiac abnormalities in people with marfans syndrome?

Answer 22

MVP, MR, aortic root dilation

Question 23

what is the most serious cardiac complication in marfans syndrome and how can you determine the risk?

Answer 23

aortic dissection - 10% risk if root >4cm

Question 24

What is the management of marfans syndrome in pregnancy?

Answer 24

• pregnancy contraindicated if aortic root >4-4.5cm. If this is the case, patients should be offered aortic root replacement prior to pregnancy
• B blockers (reduce the risk of aortic dilation) should be started in pregnancy for any woman with aortic dilation or hypertension
• regular echocardiograms
• in women with arotic root >4.5cm, elective LUSCS is generally recommended.