Transcript Approach to Cardiac Disease in Pregnancy Mehul Bhatt, MD Athens Heart Center March 13, 2009

Approach to Cardiac
Disease in Pregnancy
Mehul Bhatt, MD
Athens Heart Center
March 13, 2009
Approach to Cardiac Disease in
Pregnancy
Physiological changes in pregnancy
Systematic approach to cardiac lesions
Principal of monitoring and treatment
Individualizing treatment to each patient
Normal Physiological Changes
in Pregnancy
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Framework to understand effects of cardiac
pathology
Tremendous cardiocirculatory changes in
normal pregnancy:
• SV (increase 40-50%)
• CO (increase 30-50%)
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Examine changes at various points of
pregnancy
Normal changes in physical exam, EKG,
CXR, Echo, PA catheter
Normal Physiological Changes
in Pregnancy
Braunwald E et al. Heart Disease. 2001. pg. 2173.
Normal Physiological Changes
in Pregnancy
Braunwald E et al. Heart Disease. 2001. pg. 2173.
Normal Physiological Changes
in Pregnancy
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Changes in blood volume start by 6 weeks
Most hemodynamic changes completed by 22-25
weeks
(major underlying cardiac disease should present by
this point)
Mechanisms of cardiovascular hyperactivity:
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Estrogen levels
Elevated renin-aldosterone levels
Elevated chorionic somatomammotropin
Elevated prolactin
Fetus not necessary for changes to occur
(as evidenced from hydatidiform moles)
Normal Physiological Changes
in Pregnancy
Braunwald E et al. Heart Disease. 2001. pg. 2172.
Normal Physiological Changes
in Pregnancy
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Symptoms:
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Decreased exercise tolerance / Tiredness – increased body
weight and physiological anemia
Orthopnea – pressure of uterus on diaphragm
Palpitations – usually sinus tachycardia
Lightheadness / Syncope – compression IVC, decrease CO
Dyspnea – 76% of women at 34th week
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Physical Exam: Hyperventilation, peripheral edema, capillary
pulsations, brisk PMI, palpable RV + PA impulse, bibasilar rales
(from atelectasis), distended neck veins (promient a,v waves,
brisk x,y descents)
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May be similar changes from cardiac pathology in pregnancy
Normal Physiological Changes
in Pregnancy
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3rd heart sound in upto 90%
Systolic ejection murmur – from hyperkinetic flow
Most auscultatory changes resolved 1-2 weeks postpartum
Cutforth R et al. Heart sounds and mumurs in pregnancy. Am Heart J. 1966;71:741-747.
Normal Physiological Changes
in Pregnancy
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EKG changes
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QRS axis deviation
Small Q wave and inverted P wave in lead III
Sinus tachycardia
Increase R/S ratio in V1 and V2
CXR changes
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Straightening of left upper cardiac border
Horizontal positioning of heart
Increased lung marking
Small pleural effusion at early postpartum
Echocardiogram
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Slightly increased EDdV and ESdV
Slightly improved LV function
Enlargment of ventricular dimensions
Slight enlargement of left atrial size
Small pericardial effusion
Increased tricuspid annulus diameter
Functional tricuspid regurgiation
Elkayam U et al. Cardiac Problems in Pregnancy. 1990.34-7.
Normal Physiological Changes
in Pregnancy
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Effect of position on IVC return
Positioning in cardiac pathology
may be beneficial or detrimental
Braunwald E et al. Heart Disease. 2001. pg. 2172.
Normal Physiological Changes
in Pregnancy

Labor and Delivery:
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Pain / Anxiety – can increase CO by 50-61%
Uterine contraction – 300-500 mL infusion into central venous
system
Cardiocirculatory effects of uterine contraction:
Parameter
Change
Comments
Blood Volume
Increase
300-500 mL
Cardiac Output
Increase
30-60% increase
Heart Rate
Increase or Decrease
Blood Pressure
Increase
Peripheral Resistance
Unchanged
O2 Consumption
Increase
Elkayam U et al. Cardiac Problems in Pregnancy. 1990. 16.
SBP and DBP
100% increase
Normal Physiological Changes
in Pregnancy
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Labor and Delivery:
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Hemodynamic changes of
pregnancy less dramatic in
lateral position
Maneuvers in delivery
position depending on
cardiac pathology
Normal Physiological Changes
in Pregnancy
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Labor and Delivery
• Epidural anesthesia – systemic vasodilation
that can reduce SV
• Poorly tolerated in patient who cannot increase SV,
fixed CO
• Cesarean section – with GETA
• Reduced maternal metabolic needs and
stabilization of blood volumes
Normal Physiological Changes
in Pregnancy
Hemodynamic Changes Postpartum
Parameter
Change
Comment
Blood Volume
Decrease
Blood loss
CO
Increase
60-80% immediate
increase followed by rapid
decrease, returns to normal
levels in few weeks
SV
Increase
HR
Decrease
BP
Unchanged
SVR
Increase
Loss of low resistance
placenta
Cardiac Diseases in Pregnancy:
Basics
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Cardiac disease hinders physiological
reserves
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Increasing incidence congenital heart
disease
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Decreasing incidence of rheumatic heart
disease
Cardiac Disease in Pregnancy:
Basics
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Non-cyanotic cardiac disease
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NYHA Functional Class
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Maternal mortality
• Class I and II: 0.4%
• Class III and IV: 6.8%
Fetal mortality
• Class I: negligible
• Class IV: 30%
Cyanotic cardiac disease
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45% rate of fetal death
Low birth weight and immaturity
Cardiac Disease in Pregnancy:
Congenital Heart Disease
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Increased CO and blood volume on already stressed
hemodynamic system
Lesions with volume
overload
Atrial
septal defect
Ventricular septal defect
Patent ductus arteriosus
Lesions with
obstruction
Aortic
stenosis
Coarctation of the aorta
Pulmonary stenosis
Tetrology of Fallot
Cardiac Disease in Pregnancy:
Cardiac Lesions
Pregnancy well tolerated
(except if progress to Eisenmenger’s
syndrome)
(able to tolerate increased volume)
Pregnancy poorly tolerated
Mitral
Obstructive
regurgitation
Aortic regurgitation
Atrial septal defect
Patent ductus arteriosis
Pulmonary stenosis
Hypertrophic obstructive cardiomyopathy
(may even benefit from increased preload)
(Fixed CO)
•Mitral stenosis
•Aortic stenosis
•Coarctation of aorta
Cyanotic
•Any lesion with Eisenmenger’s syndrome
•Primary pulmonary hypertension
•Tetralogy of Fallot
Volume
limited
•Marfan’s with aortic root involvement
•Aortic dissection
Active
rheumatic carditis
Any lesion with Class III or IV symptoms
Cardiac Disease in Pregnancy:
Cardiac Lesions
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Factors that increase risk of CHF with
pregnancy:
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Age > 30 YO
Gestational age > 20 weeks
Cardiac enlargement > 55% lung space on CXR
Atrial tachycardia
Physical effort
Toxemia
Infection
Emboli
Cardiac Disease in Pregnancy:
Monitoring and Treatment
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In perfect world:
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Diagnosis of cardiac disease prior to pregnancy
Pre-pregnancy counseling of patient and partner with
obstetrics, cardiology, and anesthesia involved
Pre-pregnancy treatment
• Medical therapy
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CHF treatment
Arrhythmia management
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Valve replacement
Congenital heart disease repair
• Surgical therapy
Cardiac Disease in Pregnancy:
Monitoring and Treatment
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General objectives of treatment
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Shunts: avoid favoring R to L shunting, lower PA
pressures, avoid hypoxemia, avoid prolonged Valsalva
Obstructive Lesions: β-blockers, avoid volume
depletion, maintain preload
CHF: diuretics (only with pulmonary edema), reduce
afterload
Arrhythmias: rate and rhythm control, anticoagulation
as necessary, higher dose digoxin
Tenuous aorta (Marfan’s, aortic dissection):
β-blockers (reduce dp/dt)
Cardiac Disease in Pregnancy:
Monitoring and Treatment
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Indications for considering PA catheter:
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NYHA Functional Class II, III, IV
Mitral stenosis
Aortic stenosis
Pulmonary hypertension
Pulmonary edema
Hypoxemia
Ischemic heart disease
Intractable hypertension
Oliguria unresponsive to fluids
Risk of PA catheter:
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Increased procedural fear and pain leading to increased CO
Cardiac Disease in Pregnancy:
Monitoring and Treatment
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Labor and Delivery:
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Epidural anesthesia:
• Systemic vasodilation
• Decrease CO 25-45% even in normal patients
• Well tolerated (often beneficial):
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AR, MR, L to R shunts
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Limited ability to increase SV
R to L shunts
AS, MS
Hypertrophic CM
Pulmonary hypertension without ASD
• Poorly tolerated:
Cardiac Disease in Pregnancy:
Monitoring and Treatment
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Labor and Delivery
• Caesarian section recommended:
• Obstetrical reasons
• Anticoagulation with coumadin
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Avoid forceps, use vacuum/suction devices
• Severe fixed obstructive cardiac lesions
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Avoid vasodilation (reduced preload) with epidural
anesthesia
• Severe pulmonary HTN
• Marfan’s with dilated aorta or aortic dissection
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Avoid increased blood volume, aortic stress with
contractions
Cardiac Disease in Pregnancy:
Monitoring and Treatment
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Labor and Delivery
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Shorten stage II labor
• Prolonged valsalva
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Increase PA pressures, Increases R to L shunting
Shunts: ASD, VSD, Tetralogy of Fallot, Eisenmenger’s
Maternal Position:
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Supine versus lateral decubitus
• Consider lateral decubitus with obstructive lesions
• Consider supine with CHF
Post-delivery:
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Continue monitoring
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Increased CO (returns to normal after several weeks)
Increased SVR (with loss of placenta)
Hemorrhage risk
Cardiac Disease in Pregnancy:
Highest-Risk Cardiac Lesions
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Suprasystemic pulmonary vascular resistance
(Eisenmenger’s syndrome)
Marfan’s syndrome with dilation of the aortic
root
Peripartum cardiomyopathy with persistent
cardiac enlargement
Cardiac Disease in Pregnancy:
Peripartum Cardiomyopathy
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Incidence: 1 in 4000 pregnancies
More common after age 30
Can result in severe CHF
Clinically present by 3rd trimester
Close hemodynamic monitoring and early delivery
maybe necessary
Cardiomyopathy may persist even after delivery
High rate of recurrence so birth control
recommended
Cardiac Disease in Pregnancy:
Acute Myocardial Infarction
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Rare in pregnancy
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1 in 10,000 to 30,000 pregnancies
Coronary dissections
Thrombolytic therapy relatively contraindicated
Primary angioplasty safe after 1st trimester
with lead shielding over fetus
Cardiac Disease in Pregnancy:
Anticoagulation
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Increased thrombogenicity in pregnancy
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Increased fibrinogen
Increased factors II, VII-X
Increased von Willebrand factor
Increased endothelial cell inhibitor of tPA
Increased placental inhibitor of tPA
Decreased protein S
Same indication as in non-pregnant
Mechanical valves still particularly challenging
Cardiac Disease in Pregnancy:
Anticoagulation
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Anticoagulants:
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Warfarin
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1st trimester teratogenicity – due to low levels of Vit. K clotting
factors in early fetus
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“Coumadin embryopathy”: Facial abnormalities, optic atrophy,
mental impairment (5-25% risk)
Possibly dose related effects (one study)
Higher rates of spontaneous abortion
Unfractionated Heparin
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Used during 1st trimester to avoid coumadin embryopathy
Subcutaneous unfractionated heparin still see fatal valve
thrombosis
Cardiac Disease in Pregnancy:
Anticoagulation
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Anticoagulants
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Low molecular weight heparin (LMWH)
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Seemed easy, cost-effective, non-teratogenic
Effective in DVT, antiphospholipid syndrome in pregnancy
Safe in peri-procedural bridging in non-pregnant patient with
mechanical valve replacements
Randomized trial of LMWH in prosthetic heart valves
terminated after 12 patients enrolled secondary due to 2
deaths from prosthetic valve thrombosis
Cardiac Disease in Pregnancy:
Prosthetic Valves
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Treatment dilemma:
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Warfarin best for prevention of thromboembolic events, but fetal
safety issues
Heparin reduces fetal complications, but dosing issues increase
risk of thromboembolic events
Consider bioprosthetic valves in women of childbearing age or
planning pregnancy
Anticoagulation with mechanical valves
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Very high risk patients
Limited data
ACC / AHA Guidelines
Cardiac Disease in Pregnancy:
Prosthetic Valves
Braunwald E et al. Heart Disease. 2001. pg. 2186.
Cardiac Disease in
Pregnancy
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Framework for evaluation and
treatment
Individualized management
Anticoagulation with mechanical
valves remains challenge