Presentation on theme: "Non-ischemic cardiac disease during pregnancy"— Presentation transcript:
1 Non-ischemic cardiac disease during pregnancy Ruben J. Azocar, MDAssistant Professor of AnesthesiologyBoston University Medical Center
2 IntroductionAlthough 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 anemiaAn estrogen mediated stimulation of the renin-angiotensin system results in retention of NA and waterHR increases 10 to 20 bpm
4 CV Physiology of Pregnancy CO increase up to 45% by 24 wksThese increases begin during the 1st trimesterPeak by wks and are sustained until termIn early pregnancy an increase in SV (20-30%) is responsible to the increase in COLater in pregnancy, the increase in HR is responsible since SV decreased due to IVC compressionConcurrently 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 diseaseExertional dyspnea and orthopneaFatigue and PresyncopeLower extremity edemaa and v waves may be pronounced in CVP tracingMaximal apical impulse is displaced1st Heart sound the pulmonary component of 2nd might are accentuated3rd HS is heard in 80% of pregnant women
6 CV Physiology of Pregnancy Murmurs frequently develop during pregnancySoft, mid-systolic, and heard along the left sternal border is heard in 90% womenAnemia might accentuate itIntensity may increase as CO increasesCervical venous hums and a continuous murmur due to increased mammary blood flow may also be heardEchocardiography is warranted if:Diastolic, continuous, or loud systolic murmurs (>2/6)A fixed split 2nd soundAssociated 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 atriumIncreased transvalvular flow velocities due to the increased BVMinor degrees of atrioventricular valve regurgitation
8 CV Physiology of Pregnancy During labor:CO increases 45% above pre-labor valuesUterine contraction “boluses” the patientIt might increase CO up to 65% of pre-labor valuesThe BP increases with uterine contractions/pain
9 CV Physiology of Pregnancy Immediately after deliveryThe cardiac filling pressure increase dramatically due to the decompression of the vena cava and the return of uterine blood into the systemic circulationCO might increase to 80% of pre-labor valuesThe cardiovascular adaptations associated with pregnancy regress by approximately 6 weeks after delivery
10 Physiology of Pregnancy Pregnancy is also a hypercoagulable stateDecreased in Protein S activityStasisVenous hypertension
11 The problemA 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 disorderAdverse maternal outcomes included: pulmonary edema, sustained brady or tachyarrhythmias, stroke, cardiac arrest, or deathAdverse 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 events13% of completed pregnanciesMore 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 higherThese events occurred in:4% of the women with none of these risk factors27 % of those with one risk factor62 % of those with two or more risk factorsThe 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 complicationsOther predictors of adverse fetal outcomes included:The use of anticoagulant drugs throughout pregnancySmoking during pregnancyMultiple gestationMother’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 EvaluationThe evaluation of a woman with clinically significant valvular heart disease should occur before conception and entail a full cardiac assessmentThe history should focus on the patient's exercise capacity, current or past evidence of heart failure, and associated arrhythmiasCardiac hemodynamics, including PAP and the severity of valve dysfunction, should be assessed by echoExercise testing may be useful if the history is inadequate to allow an assessment of functional capacityDuring 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 StenosisRheumatic MS is the most common valvular abnormality in pregnant women (60%)Associated with pulmonary congestion, edema, and atrial arrhythmias during pregnancy or soon after deliveryThe 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 toleranceIncreases in the maternal HR decrease the diastolic filling period, further increasing left atrial pressure and decreasing COThe increased atrial pressure may cause arrhythmias
16 Mitral StenosisMortality among pregnant women with minimal symptoms is less than 1%Predictors of adverse maternal outcomesMitral valve area less than 1.5 cm2Abnormal functional class before pregnancyFetal mortality increases with deteriorating maternal functional capacity30 % 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 overloadDiuretic therapy but avoiding hypotension and tachycardiaNA+ restrictionReduction of physical activityBeta-blockers decrease HR and prolong the diastolic filling period which provides symptomatic benefit
18 Mitral StenosisDevelopment of AF requires prompt treatment, including cardioversion.Beta-blockers and digoxin for rate controlProcainamide and quinidine are frequently used if suppressive antiarrhythmic therapy is neededDue to the increased risk of systemic embolism in patients with MS and AF anticoagulant therapy is indicated
19 Mitral StenosisNYHA class III / IV or a valve area of less than 1.0 cm2Percutaneous balloon mitral valvuloplasty (PBMV) or valve surgery BEFORE conceiving appear to allow pregnancy with fewer complications than women treated medicallyPBMV, during the 2nd trimester, has been associated with normal deliveries and excellent fetal outcomesFetal risks associated with exposure to radiation may be reduced by avoiding exposure during the first half of pregnancyThe uterus must be shielded and the patient should be informed about the possible risksMitral valvuloplasty has also been performed under TEE guidance
20 Mitral StenosisOpen cardiac surgery has been performed during pregnancy for severe MSMaternal outcomes are similar to the non-pregnantFetal 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 planICU consultationVaginal delivery is the usual approachHemodynamic goals:Avoidance of tachycardia and fluid overloadPreservation sinus rhythmIncrease 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 PACLabor and delivery is associated with an increase of 8 to 10 mm Hg in the left atrial and pulmonary wedge pressuresPAC 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 controlA mixture of LA and opioids is idealPain control and minimization of BV/CO increase after deliveryAssisted-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 RegurgitationMost commonly due to mitral-valve prolapse and is usually well tolerated during pregnancy because of the reduction in SVRWomen 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 pregnancyDiuretics and vasodilators may be indicatedOutcome data that would help to guide clinical decision making in this area are lacking.
25 Aortic StenosisCongenital valvular abnormalities are usually the cause of AS in young women in the USSevere AS is poorly tolerated during pregnancyMaternal and perinatal mortality of 17% and 32% have been reportedThe pressure gradient is responsible for the HD changes seen in ASThe increased LVSP needed to maintain systemic arterial blood pressure increases stress in the ventricular wallLt ventricular hypertrophy develops leading to diastolic dysfunction, fibrosis, diminish coronary blood flow reserve and late systolic failure
26 Aortic StenosisPatients who are symptomatic or who have a peak outflow gradient of more than 50 mm Hg are advised to delay conception until after surgical correctionTermination of pregnancy should be strongly considered if the patient is symptomatic before the end of the 1st trimesterAortic-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 timeAtrial “kick” is responsible for up to 40% of ventricular filling in this patientsBaseline SVR
28 Aortic StenosisThe normal physiological changes of pregnancy can precipitate heart failure in patient with severe ASThe 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 consumptionIncreases LVEDPIschemia might result
29 Aortic Stenosis Vaginal delivery is preferred Monitoring: Instrumental delivery to avoid hemodynamic changes of the valsalva manuverOxytocin may decrease SVR an increase PAPMonitoring:A-line?CVP ?PAC
30 Aortic Stenosis Epidural analgesia Pain control and also minimizes BV/CO increase after deliveryAvoid epinephrine “test dose”Careful titration to avoid sudden decrease of SVRDilute LA with opioids to minimize sympathectomy
31 Aortic Stenosis Cesarean section GA has traditionally being advocated to avoid sudden decreases of SVROpiod based inductionFetal depression. Pediatric team must be awareCase reports of epidural anesthesia with positive outcomesCareful titration of LA and fluid replacement/vasopressors to counteract sympathectomyPhenylephrine possible a better choice over ephedrine
32 Aortic RegurgitationAI may be due to a dilated Ao annulus (as in Marfan's syndrome), a bicuspid Ao valve, or previous endocarditisThe reduced SVR of pregnancy reduces the volume of regurgitated bloodWomen 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 InsufficiencyIsolated AI can usually be managed with vasodilators and diureticsACE inhibitors should be discontinued during pregnancy, and other agents, such as hydralazine or nifedipine, should be substitutedClinical and echo assessment should be performed before conception in women with AI due to Marfan's syndromeEven 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 eventsSecondary 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 objectivesMaintain 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 PHTNThe 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 returnAir 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 administrationVaginal deliveryPain control with a mixture of local anesthetics in a low concentration and opioids via epiduralForceps delivery, which decreases patient effort and hemodynamic consequences, is the technique of choice.
38 Pulmonary Hypertension Cesarean DeliveryBoth 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 anesthesiaBased on opioidsLidocaine (1 mg/kg) reduces pulmonary and hemodynamic reactions during intubationInduction can be complemented with pentothal, propofol, or etomidateSuccinylcholine can be used for intubationAnesthesia 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 therapyWomen with mechanical valves have a higher rate of thromboembolism and higher 10-year mortality, despite a lower rate of valve lossPregnancy does not appear to increase the rate of failure of mechanical prostheses or homograft nor accelerates the deterioration of bioprosthetic valvesPregnancy 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 AnticoagulationThere are no results of clinical trials to guide the choice of anticoagulant therapy during pregnancyMonitoring is required in order to assess whether the antithrombotic effect is adequateThe effective doses of these drugs change during pregnancy because of changes in intravascular volume and body weightIn 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 WarfarinIn women with mechanical valves the use of warfarin throughout pregnancy was associated with the greatest maternal protectionRisk of thromboembolism, 3.9%, risk of death, 1.8%Warfarin crosses the placentaFetal deformities and CNS abnormalitiesHigh rate of fetal loss (30%) including spontaneous abortions, stillbirths, and neonatal deathsExposure to warfarin between wks of gestation was associated with a rate of fetal loss that was twice that associated with the use of unfractionated heparinFetopathic effects of warfarin use (nasal hypoplasia and bone stippling) occurred in approximately 6 % of cases,
43 HeparinIf 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 thromboembolismLong-term use of heparin is associated with maternal risks of HIT and osteopenia.
44 LMWHLow-molecular-weight heparins have been used successfully to treat DVT during pregnancyLower risks of thrombocytopenia and osteopenia than unfractionated heparinProbably safe for the fetusThere 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 pregnancyNor 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 recommendEncourage education of the prospective parents and their involvement in the decision-making processWarfarin 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 heparinThis option was suggested because of medicolegal concern relating to the "off-label" use of warfarin and the risk of embryopathy.
46 Peripartum cardiomyopathy Unknown etiologyIncidence 25-75/ in some seriesDiagnosis:Biventricular dilated cardiomyopathy in 3rd trimester or in puerperiumAbsence of prior cardiac disease50% good prognosis if early reversion of symptoms but % mortalityTreatment: Supportive