1. Non-ischemic cardiac disease during pregnancy
Ruben J. Azocar, MD
Assistant Professor of Anesthesiology
Boston University Medical Center

2. Introduction
Although the prevalence of clinically significant maternal heart disease during pregnancy is probably less than 1% its presence increases the risk of adverse maternal, fetal, and neonatal outcomes

3. CV Physiology of Pregnancy
Blood volume increases 30 to 50%
Plasma volume increase more than RBC mass leading to physiologic anemia
An estrogen mediated stimulation of the renin-angiotensin system results in retention of NA and water
HR increases 10 to 20 bpm

4. CV Physiology of Pregnancy
CO increase up to 45% by 24 wks
These increases begin during the 1st trimester
Peak by wks and are sustained until term
In early pregnancy an increase in SV (20-30%) is responsible to the increase in CO
Later in pregnancy, the increase in HR is responsible since SV decreased due to IVC compression
Concurrently there is a substantial reduction in SVR by 21% with decreases in BP and decreases in PVR by 34%

5. CV Physiology of Pregnancy
Symptoms and PE of normal pregnancy mimic cardiac disease
Exertional dyspnea and orthopnea
Fatigue and Presyncope
Lower extremity edema
a and v waves may be pronounced in CVP tracing
Maximal apical impulse is displaced
1st Heart sound the pulmonary component of 2nd might are accentuated
3rd HS is heard in 80% of pregnant women

6. CV Physiology of Pregnancy
Murmurs frequently develop during pregnancy
Soft, mid-systolic, and heard along the left sternal border is heard in 90% women
Anemia might accentuate it
Intensity may increase as CO increases
Cervical venous hums and a continuous murmur due to increased mammary blood flow may also be heard
Echocardiography is warranted if:
Diastolic, continuous, or loud systolic murmurs (>2/6)
A fixed split 2nd sound
Associated with symptoms or an abnormal EKG

7. CV Physiology of Pregnancy
In normal pregnant women, echocardiography demonstrates:
Minor increases in the left and right ventricular diastolic dimensions (within the normal range)
A slight decrease in the LVES dimension and a minimal increase in the size of the left atrium
Increased transvalvular flow velocities due to the increased BV
Minor degrees of atrioventricular valve regurgitation

8. CV Physiology of Pregnancy
During labor:
CO increases 45% above pre-labor values
Uterine contraction “boluses” the patient
It might increase CO up to 65% of pre-labor values
The BP increases with uterine contractions/pain

9. CV Physiology of Pregnancy
Immediately after delivery
The cardiac filling pressure increase dramatically due to the decompression of the vena cava and the return of uterine blood into the systemic circulation
CO might increase to 80% of pre-labor values
The cardiovascular adaptations associated with pregnancy regress by approximately 6 weeks after delivery

10. Physiology of Pregnancy
Pregnancy is also a hypercoagulable state
Decreased in Protein S activity
Stasis
Venous hypertension

11. The problem
A Canadian analyses of the outcomes of pregnancy identified predictors of adverse maternal and fetal outcomes in a group of women with congenital or acquired heart disease (546 women and 599 pregnancies)
Approximately 40% of the women had a primary valve disorder
Adverse maternal outcomes included: pulmonary edema, sustained brady or tachyarrhythmias, stroke, cardiac arrest, or death
Adverse fetal outcomes included: premature birth, intrauterine growth retardation, respiratory distress syndrome, intraventricular hemorrhage, and death

12. Maternal outcomes 13% of completed pregnancies More likely if:
Incidence of adverse maternal cardiac events
13% of completed pregnancies
More likely if:
EF below 40%
Left heart obstruction (AS with a valve area of less than 1.5 cm2 or MS with a valve area of less than 2.0 cm2)
Previous cardiovascular events (heart failure, tia, or stroke)
NYHA class II or higher
These events occurred in:
4% of the women with none of these risk factors
27 % of those with one risk factor
62 % of those with two or more risk factors
The 3 women that died had two or more risk factors

13. Fetal outcomes The use of anticoagulant drugs throughout pregnancy
Abnormal functional capacity (NYHA class II or higher) and left heart obstruction were also predictors of neonatal complications
Other predictors of adverse fetal outcomes included:
The use of anticoagulant drugs throughout pregnancy
Smoking during pregnancy
Multiple gestation
Mother’s age (> 35 yrs or < 20 yrs)
Fetal mortality was:
4 % among pregnancies in women with one or more of these risk factors,
2% among those with none of these risk factors

14. Evaluation
The evaluation of a woman with clinically significant valvular heart disease should occur before conception and entail a full cardiac assessment
The history should focus on the patient's exercise capacity, current or past evidence of heart failure, and associated arrhythmias
Cardiac hemodynamics, including PAP and the severity of valve dysfunction, should be assessed by echo
Exercise testing may be useful if the history is inadequate to allow an assessment of functional capacity
During pregnancy evaluation each trimester and whenever there is a change in symptoms, in order to assess any deterioration in maternal cardiac status is the rule

15. Mitral Stenosis
Rheumatic MS is the most common valvular abnormality in pregnant women (60%)
Associated with pulmonary congestion, edema, and atrial arrhythmias during pregnancy or soon after delivery
The increased BV load and CO associated with pregnancy lead to an increase in left atrial volume and pressure, elevated pulmonary venous filling pressures, dyspnea, and decreased exercise tolerance
Increases in the maternal HR decrease the diastolic filling period, further increasing left atrial pressure and decreasing CO
The increased atrial pressure may cause arrhythmias

16. Mitral Stenosis
Mortality among pregnant women with minimal symptoms is less than 1%
Predictors of adverse maternal outcomes
Mitral valve area less than 1.5 cm2
Abnormal functional class before pregnancy
Fetal mortality increases with deteriorating maternal functional capacity
30 % when the mother has NYHA class IV

17. Mitral Stenosis For women with mild or moderate symptoms
Medical therapy is directed to the treatment of volume overload
Diuretic therapy but avoiding hypotension and tachycardia
NA+ restriction
Reduction of physical activity
Beta-blockers decrease HR and prolong the diastolic filling period which provides symptomatic benefit

18. Mitral Stenosis
Development of AF requires prompt treatment, including cardioversion.
Beta-blockers and digoxin for rate control
Procainamide and quinidine are frequently used if suppressive antiarrhythmic therapy is needed
Due to the increased risk of systemic embolism in patients with MS and AF anticoagulant therapy is indicated

19. Mitral Stenosis
NYHA class III / IV or a valve area of less than 1.0 cm2
Percutaneous balloon mitral valvuloplasty (PBMV) or valve surgery BEFORE conceiving appear to allow pregnancy with fewer complications than women treated medically
PBMV, during the 2nd trimester, has been associated with normal deliveries and excellent fetal outcomes
Fetal risks associated with exposure to radiation may be reduced by avoiding exposure during the first half of pregnancy
The uterus must be shielded and the patient should be informed about the possible risks
Mitral valvuloplasty has also been performed under TEE guidance

20. Mitral Stenosis
Open cardiac surgery has been performed during pregnancy for severe MS
Maternal outcomes are similar to the non-pregnant
Fetal loss in 10 to 30 % of cases

21. MS: Anesthesia management
Careful clinical evaluation early on in conjunction with the OB team to have a clear plan
ICU consultation
Vaginal delivery is the usual approach
Hemodynamic goals:
Avoidance of tachycardia and fluid overload
Preservation sinus rhythm
Increase of BV, CO and HR during pregnancy and labor may result in pulmonary congestion, tachycardia and atrial fibrillation

22. MS: Anesthesia management
Monitoring:
A-LINE and probably PAC
Labor and delivery is associated with an increase of 8 to 10 mm Hg in the left atrial and pulmonary wedge pressures
PAC used before and during delivery facilitates the management of hemodynamics in women with advanced disease

23. MS: Anesthesia management
Epidural anesthesia to achieve effective pain control
A mixture of LA and opioids is ideal
Pain control and minimization of BV/CO increase after delivery
Assisted-delivery devices during the second stage of delivery eliminate hemodynamic effects of valsalva maneuver during “pushing”
Cesarean section should be performed when there are obstetrical indications for it

24. Mitral Regurgitation
Most commonly due to mitral-valve prolapse and is usually well tolerated during pregnancy because of the reduction in SVR
Women with symptomatic MR may benefit from mitral-valve surgery (preferably repair )before becoming pregnant.
However, LV dysfunction associated with MR is unlikely to improve after surgery and will increase maternal risk during pregnancy
Diuretics and vasodilators may be indicated
Outcome data that would help to guide clinical decision making in this area are lacking.

25. Aortic Stenosis
Congenital valvular abnormalities are usually the cause of AS in young women in the US
Severe AS is poorly tolerated during pregnancy
Maternal and perinatal mortality of 17% and 32% have been reported
The pressure gradient is responsible for the HD changes seen in AS
The increased LVSP needed to maintain systemic arterial blood pressure increases stress in the ventricular wall
Lt ventricular hypertrophy develops leading to diastolic dysfunction, fibrosis, diminish coronary blood flow reserve and late systolic failure

26. Aortic Stenosis
Patients who are symptomatic or who have a peak outflow gradient of more than 50 mm Hg are advised to delay conception until after surgical correction
Termination of pregnancy should be strongly considered if the patient is symptomatic before the end of the 1st trimester
Aortic-valve replacement and palliative aortic balloon valvuloplasty have been performed during pregnancy with associated maternal and fetal risk

27. Aortic Stenosis Hemodynamic goals: Maintain normovolemia NSR
Tachycardia decrease dyastolic filling time
Atrial “kick” is responsible for up to 40% of ventricular filling in this patients
Baseline SVR

28. Aortic Stenosis
The normal physiological changes of pregnancy can precipitate heart failure in patient with severe AS
The further increase of CO and BV during labor in face of the fixed CO of AS patients may precipitate:
Tachycardia which decreased diastolic time (and coronary perfusion time) and increases O2 consumption
Increases LVEDP
Ischemia might result

29. Aortic Stenosis Vaginal delivery is preferred Monitoring:
Instrumental delivery to avoid hemodynamic changes of the valsalva manuver
Oxytocin may decrease SVR an increase PAP
Monitoring:
A-line
?CVP ?PAC

30. Aortic Stenosis Epidural analgesia
Pain control and also minimizes BV/CO increase after delivery
Avoid epinephrine “test dose”
Careful titration to avoid sudden decrease of SVR
Dilute LA with opioids to minimize sympathectomy

31. Aortic Stenosis Cesarean section
GA has traditionally being advocated to avoid sudden decreases of SVR
Opiod based induction
Fetal depression. Pediatric team must be aware
Case reports of epidural anesthesia with positive outcomes
Careful titration of LA and fluid replacement/vasopressors to counteract sympathectomy
Phenylephrine possible a better choice over ephedrine

32. Aortic Regurgitation
AI may be due to a dilated Ao annulus (as in Marfan's syndrome), a bicuspid Ao valve, or previous endocarditis
The reduced SVR of pregnancy reduces the volume of regurgitated blood
Women with an abnormal functional capacity or left ventricular dysfunction are predicted to have a high risk of abnormal maternal outcomes, but few data concerning this population are available

33. Aortic Insufficiency
Isolated AI can usually be managed with vasodilators and diuretics
ACE inhibitors should be discontinued during pregnancy, and other agents, such as hydralazine or nifedipine, should be substituted
Clinical and echo assessment should be performed before conception in women with AI due to Marfan's syndrome
Even in the absence of overt cardiac abnormalities, this syndrome predisposes women to unpredictable, but increased, risk during pregnancy.

34. Pulmonary hypertension
PHTN is associated with high maternal mortality (33 to 40 %), as well as with an increased rate of adverse neonatal events
Secondary PHTN due to valvular disease is associated with an increased rate of adverse maternal events, but the absolute risk of such events is unclear.
A systolic pulmonary-artery pressure that is more than 75 % as high as the systemic pressure places the woman at high risk.

35. Pulmonary hypertension
Hemodynamic objectives
Maintain the PAP as low as possible and the systemic pressure within the 15% above and below the basal level (the systemic pressure should always be higher than pulmonary pressure)
Avoid dysrhythmias and tachycardia, and maintain sinus rhythm

36. Pulmonary hypertension
Pregnancy and labor CV changes against goals:
Uterine contraction after delivery returns a large bolus of blood to the circulation. This can be poorly tolerated in patients with severe PHTN
The sudden hypervolemia can be treated with vasodilators, such as nitroglycerine, and diuretics.
A BP cuff inflated between the arterial and venous pressures around the thighs, can suddenly and reversibly decrease RV filling by reducing venous return
Air or amniotic fluid embolism could acutely increase pulmonary pressure

37. Pulmonary hypertension
Monitoring:
a-line and CVP or PAC should be used for monitoring or for drug administration
Vaginal delivery
Pain control with a mixture of local anesthetics in a low concentration and opioids via epidural
Forceps delivery, which decreases patient effort and hemodynamic consequences, is the technique of choice.

38. Pulmonary Hypertension
Cesarean Delivery
Both general and epidural anesthesia have been used for cesarean delivery in patients with pulmonary hypertension.
The surgical procedure can lead to excessive bleeding and hypovolemia

39. Pulmonary hypertension
Induction of general anesthesia
Based on opioids
Lidocaine (1 mg/kg) reduces pulmonary and hemodynamic reactions during intubation
Induction can be complemented with pentothal, propofol, or etomidate
Succinylcholine can be used for intubation
Anesthesia could be maintained with use of short acting narcotic infusion, volatile anesthetics and/or propofol infusion

40. Prosthetic Heart Valves
Bioprostheses are not as durable as mechanical prostheses, but eliminate the need for anticoagulant therapy
Women with mechanical valves have a higher rate of thromboembolism and higher 10-year mortality, despite a lower rate of valve loss
Pregnancy does not appear to increase the rate of failure of mechanical prostheses or homograft nor accelerates the deterioration of bioprosthetic valves
Pregnancy in a woman with a mechanical valve is associated with an estimated maternal mortality of 1 to 4% with death usually resulting from complications of prosthetic-valve thrombosis.

41. Anticoagulation
There are no results of clinical trials to guide the choice of anticoagulant therapy during pregnancy
Monitoring is required in order to assess whether the antithrombotic effect is adequate
The effective doses of these drugs change during pregnancy because of changes in intravascular volume and body weight
In a series of 976 women with a total of 1234 pregnancies the use of any anticoagulant therapy resulted in major bleeding in 2.5 % of the pregnancies, with bleeding usually occurring at the time of delivery

42. Warfarin
In women with mechanical valves the use of warfarin throughout pregnancy was associated with the greatest maternal protection
Risk of thromboembolism, 3.9%, risk of death, 1.8%
Warfarin crosses the placenta
Fetal deformities and CNS abnormalities
High rate of fetal loss (30%) including spontaneous abortions, stillbirths, and neonatal deaths
Exposure to warfarin between wks of gestation was associated with a rate of fetal loss that was twice that associated with the use of unfractionated heparin
Fetopathic effects of warfarin use (nasal hypoplasia and bone stippling) occurred in approximately 6 % of cases,

43. Heparin
If heparin rather than warfarin was used during the 1st trimester, the risks of maternal thromboembolism and maternal death more than doubled (9.2% and 4.2% respectively)
The use of adjusted-dose heparin (titrated to a therapeutic activated PTT) throughout pregnancy was associated with the highest risks of maternal thromboembolism and maternal death (25% and 7 % respectively)
A large proportion of the women had ball-and-cage valves or older single-tilting-disk valves that are known to carry a high risk of thromboembolism
Long-term use of heparin is associated with maternal risks of HIT and osteopenia.

44. LMWH
Low-molecular-weight heparins have been used successfully to treat DVT during pregnancy
Lower risks of thrombocytopenia and osteopenia than unfractionated heparin
Probably safe for the fetus
There are insufficient data from studies of women with prosthetic heart valves to support the efficacy of this therapy or the use of any type of heparin throughout pregnancy
Nor has the use of low-molecular-weight heparin been studied in women with AF associated with valvular disease during pregnancy.

45. Anticoagulation Guidelines
Although definitive data are lacking authors recommend
Encourage education of the prospective parents and their involvement in the decision-making process
Warfarin to achieve a target INR of 2.0 to 3.0 throughout most of the pregnancy.
The only exceptions are the periods between 6 and 12 weeks of pregnancy and after 36 weeks of pregnancy, when they would opt for the closely monitored use of unfractionated heparin
This option was suggested because of medicolegal concern relating to the "off-label" use of warfarin and the risk of embryopathy.

46. Peripartum cardiomyopathy
Unknown etiology
Incidence 25-75/ in some series
Diagnosis:
Biventricular dilated cardiomyopathy in 3rd trimester or in puerperium
Absence of prior cardiac disease
50% good prognosis if early reversion of symptoms but % mortality
Treatment: Supportive

47. Questions?
Thank you