approach to cardiac diseases in pregnancy
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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
Framework to understand effects of cardiac pathology
Tremendous cardiocirculatory changes in normal pregnancy:
• SV (increase 40-50%) • CO (increase 30-50%)
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
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:• 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
Symptoms: • 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
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)
May be similar changes from cardiac pathology in pregnancy
Normal Physiological Changes in Pregnancy
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
EKG changes• 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• Straightening of left upper cardiac border
• Horizontal positioning of heart
• Increased lung marking
• Small pleural effusion at early postpartum Echocardiogram
• 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
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:• 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 SBP and DBP
Peripheral Resistance Unchanged
O2 Consumption Increase 100% increase
Elkayam U et al. Cardiac Problems in Pregnancy. 1990. 16.
Normal Physiological Changes in Pregnancy
Labor and Delivery:
• Hemodynamic changes of pregnancy less dramatic in lateral position
• Maneuvers in delivery position depending on cardiac pathology
Normal Physiological Changes in Pregnancy
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
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
Hemodynamic Changes Postpartum
Cardiac Diseases in Pregnancy:Basics
Cardiac disease hinders physiological reserves
Increasing incidence congenital heart disease
Decreasing incidence of rheumatic heart disease
Cardiac Disease in Pregnancy:Basics
Non-cyanotic cardiac disease• NYHA Functional Class
• 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• 45% rate of fetal death
• Low birth weight and immaturity
Cardiac Disease in Pregnancy:Congenital Heart Disease
Increased CO and blood volume on already stressed hemodynamic system
Lesions with volume overload
Lesions with obstruction
Atrial septal defectVentricular septal defectPatent ductus arteriosus
Aortic stenosisCoarctation of the aortaPulmonary stenosisTetrology 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 regurgitationAortic regurgitationAtrial septal defectPatent ductus arteriosisPulmonary stenosisHypertrophic obstructive cardiomyopathy (may even benefit from increased preload)
Obstructive (Fixed CO)•Mitral stenosis
•Aortic stenosis
•Coarctation of aortaCyanotic
•Any lesion with Eisenmenger’s syndrome
•Primary pulmonary hypertension
•Tetralogy of FallotVolume limited
•Marfan’s with aortic root involvement
•Aortic dissectionActive rheumatic carditisAny lesion with Class III or IV symptoms
Cardiac Disease in Pregnancy:Cardiac Lesions
Factors that increase risk of CHF with pregnancy:• 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
In perfect world: • 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
• CHF treatment
• Arrhythmia management
• Surgical therapy• Valve replacement
• Congenital heart disease repair
Cardiac Disease in Pregnancy:Monitoring and Treatment
General objectives of treatment• 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
Indications for considering PA catheter:• 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:• Increased procedural fear and pain leading to increased CO
Cardiac Disease in Pregnancy:Monitoring and Treatment
Labor and Delivery:
• Epidural anesthesia:
• Systemic vasodilation
• Decrease CO 25-45% even in normal patients
• Well tolerated (often beneficial):
• AR, MR, L to R shunts
• Poorly tolerated:
• Limited ability to increase SV
• R to L shunts
• AS, MS
• Hypertrophic CM
• Pulmonary hypertension without ASD
Cardiac Disease in Pregnancy:Monitoring and Treatment
Labor and Delivery
• Caesarian section recommended:
• Obstetrical reasons
• Anticoagulation with coumadin• Avoid forceps, use vacuum/suction devices
• Severe fixed obstructive cardiac lesions• Avoid vasodilation (reduced preload) with epidural
anesthesia
• Severe pulmonary HTN
• Marfan’s with dilated aorta or aortic dissection• Avoid increased blood volume, aortic stress with
contractions
Cardiac Disease in Pregnancy:Monitoring and Treatment
Labor and Delivery• Shorten stage II labor
• Prolonged valsalva• Increase PA pressures, Increases R to L shunting• Shunts: ASD, VSD, Tetralogy of Fallot, Eisenmenger’s
• Maternal Position:• Supine versus lateral decubitus
• Consider lateral decubitus with obstructive lesions• Consider supine with CHF
• Post-delivery:• Continue monitoring
• Increased CO (returns to normal after several weeks)• Increased SVR (with loss of placenta)• Hemorrhage risk
Cardiac Disease in Pregnancy:Highest-Risk Cardiac Lesions
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
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
Rare in pregnancy• 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
Increased thrombogenicity in pregnancy• 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
Anticoagulants:• Warfarin
• 1st trimester teratogenicity – due to low levels of Vit. K clotting factors in early fetus
• “Coumadin embryopathy”: Facial abnormalities, optic atrophy, mental impairment (5-25% risk)
• Possibly dose related effects (one study)
• Higher rates of spontaneous abortion
• Unfractionated Heparin
• Used during 1st trimester to avoid coumadin embryopathy
• Subcutaneous unfractionated heparin still see fatal valve thrombosis
Cardiac Disease in Pregnancy:Anticoagulation
Anticoagulants• Low molecular weight heparin (LMWH)
• 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
Treatment dilemma:• 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• 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
Framework for evaluation and treatment
Individualized management
Anticoagulation with mechanical valves remains challenge
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