Feb 18 2014

Cardiac diseases in pregnancy

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  • 1. Cardiac Diseases in Pregnancy Dr. Harris N Suharjono 2013
  • 2. Content of lecture:  Significance of heart disease in pregnancy?  Physiology adaptation  Preconception care.  Antenatal care with cardiac problem  Specific heart problems  Anticoagulation therapy  General advice for Medical Officers
  • 3. How significant is heart disease in pregnancy?  Accounts for 12% of maternal death in 1996.  Commonest cause of indirect maternal death in Malaysia  In Sarawak there were a total of 9 maternal deaths from heart diseases in the 3 years period between 2010-2012
  • 4. How common? •Coronary artery disease is uncommon in pre- menopausal women of child-bearing age. •Majority of cardiac conditions encountered during pregnancy will be either congenital heart disease or rheumatic valvular heart disease. •Cardiac complications result from hemodynamic changes that occur during pregnancy.
  • 5. CVS adaptation to pregnancy Cardiac output Increased by 45% Stroke volume increased Heart rate Increase by10-20 bpm Blood pressure Reduced in the 1st & 2nd trimester. CVP static SVR & PVR Reduced 25-30% sr,.colloid oncotic pressure Reduced 10-15%
  • 6. FIGURE1Plasmavolumeandredbloodcell(RBC)increaseduringthetrimestersof pregnancy.Theplasmavolumeincreasestoapproximately50%abovebaselinebythesecond trimesterandthenvirtuallyplateausuntildelivery.
  • 7. FIGURE2Hemodynamicchangesduringpregnancyrelatetoincreasedcardiacoutputanda fallinperipheralresistance.Bloodpressureinmostpatientsremainsthesameorfalls slightly.Venouspressureinthelegsincreases,causingpedal edemainmanypatients.
  • 8. Misleading features during pregnancy: Dyspnoea and tachycardia Displacement of apex beat Bounding/collapsing pulse Third heart sound, ejection systolic murrmur, ectopics,
  • 9. Misleading features during pregnancy: ECG: Ectopics Q-wave and inverted T , ST-depression, QRS axis left shift. CXR: Increased pulmonary vascular marking Slight cardiomegaly
  • 10. Preconception counselling:  Counseling plays an important role!!!  Should be referred by cardiologist or physician to the PPC Clinic, if the patient is keen to embark on a pregnancy  Estimate the risk during pregnancy  Any optimization needed?  Contraception necessary if advised not to conceive
  • 11. Contraception: Surgical: vasectomy BTL -Best, low failure rate (LFR) -Laparoscopic/minilap Barrier method: condom, spermicides Compliance issues, High failure rate (HFR). COCP: POP: /Implanon NXT Avoid in IHD, valvular heart disease and Pulmonary hypertension Very useful IUCD/LNG-IUS (Mirena) LFR, contraindicated in prosthatic valve, endocarditis.
  • 12. High Risk Heart Diseases Women with the following conditions are usually advised to avoid pregnancy. Pulmonary hypertension (>60% systemic pressure) Dilated cardiomyopathy, ejection fraction <40% Symptomatic obstructive lesions (delay pregnancy until the obstruction has been corrected)  Aortic stenosis  Mitral stenosis  Pulmonary stenosis  Coarctation of the aorta Marfan syndrome with aortic root >40 mm diameter Cyanotic lesions
  • 13. Indicators of heart disease: Symptoms:  Dypsnoea  Orthopnea  PND  Haemoptysis  Syncope  Chest pain Signs: Cyanosis Clubbing Persistent neck vein distension Loud diastolic murmur Cardiomegaly Arrythmia
  • 14. Consider termination if:  Pulmonary hypertension  Eisenmenger syndrome.  Cyanotic heart disease.  LVEF <40%  Marfan Syndrome with aortic root more than 4cm.
  • 15. Risk categorisation: Low Risk: ASD VSD PDA MS Mod-High Risk: MS with AF Artificial valve COA Previous MI
  • 16. Antenatal care:  Combined clinic  Precipitating factor of heart failure  Watch out for dangerous periods  Dental care  Rest/ diet/ smoke  Contraception  Planning of delivery (mode) always get anesthetic review/opinion  Multidisciplinary Team approach maybe necessary in high risk patients  COMPLIANCE to follow up is important
  • 17. CVS drugs safety profile in pregnancy: Beta-blockers safe Digoxin safe Diuretics Use judiciously Ace-i unsafe Calcium antagonist Use judiciously Adenosine safe Lidocaine safe Procainamide safe Quinidine Safe Amiodarone unsafe
  • 18. Mode of Delivery • Formostpatients,vaginaldeliveryfeasibleandpreferable. • Caesareansectionindicatedonlyforobstetricreasons,exceptthefollowing. o Patientanticoagulatedwithwarfarin o Patientwithdilatedunstableaorta(e.g.,Marfansyndrome) o Severepulmonaryhypertension o Severeobstructivelesionsuchasaorticstenosis • High-riskpatientsshouldbedeliveredincenterwithexpertisetomonitor hemodynamicchangesandintervenewhennecessary. • Noconsensusregardingantibioticprophylaxisattimeofdelivery,butmany institutionsroutinelygive.
  • 19. Hemodynamic changes during labour and delivery • Hemodynamic changes often abrupt. • With uterine contraction, up to 500 mL of blood may be released into circulation, causing rapid increase in cardiac output and blood pressure. • Cardiac output often 50% above baseline during 2nd stage of labour and may be even higher at time of delivery. • During normal vaginal delivery, about 400 ml of blood is lost. • With caesarean section, about 800 ml of blood is lost. • After delivery of baby, abrupt increase in venous return (autotransfusion from uterus & baby no longer compresses inferior vena cava). • Autotransfusion of blood continues for up to 24 to 72 hours after delivery, and this is when pulmonary oedema may occur.
  • 20. Intra-partum:  Delivery in specialist hospitals  Fluid management important  Lateral position if symptmatic  Ensure good analgesia  Oxygen maybe necessary  CCU maybe required post delivery  Use syntocinon and avoid syntometrine  Shortened second stage in some cases
  • 21. Intra-partum:  IOL and Mode of delivery generally follow obstetric indication  SBE prophylaxis: IV Ampicillin 1 g & gentamicin 1.5 mg/Kg (max 120mg) followed by ampicillin 500mg 6 hourly till delivery.  If allergic to penicillin: IV vancomycin1g over 2 hours.  SBE prophylaxis only necessary in some cases
  • 22. Postpartum:  HIGH RISK period!!!!  CCU care  Counseling for contraception needs  Encourage to limit number of pregnancy and BTL  Breast feeding not contraindicated.  High Risk E-discharge and home visits compulsory  PPC clinic appointment if still keen on future pregnancy  Family planning clinic appointment (encourage BTL)
  • 23. Specific conditions:  Atrial fibrillation (AF)  Valvular heart disease  Mitral stenosis  Mitral regurgitation  Aortic stenosis  Aortic regurgitation
  • 24. Atrial Fibrillation  Usually associated with another underlying cause, such as mitral stenosis, congenital heart disease, or hyperthyroidism.  Antithrombotic therapy recommended.  Use heparin in 1st trimester and last month of pregnancy. Subcutaneous unfractionated heparin 10,000 to 20,000 units every 12 hours, adjusted to achieve APTT 1.5-2.0 times control.  Use oral anticoagulant during 2nd trimester. Target INR 2.0-3.0.  Control ventricular rate with digoxin, calcium channel antagonist, or beta blocker.
  • 25. Valvular heart Disease  Most can be managed with conservative medical measures.  Symptomatic or severe valvular lesions should be rectified before conception and pregnancy whenever possible.  Drugs should be avoided when possible.
  • 26. Mitral Stenosis  Mild to moderate mitral stenosis can be managed with diuretics and cardio selective beta blockers.  Severe mitral stenosis should undergo PTMC before conception, if possible.  PTMC recommended if develop severe symptoms during pregnancy.
  • 27. Mitral Regurgitation  Can usually be managed medically with diuretics.  If surgery is required, repair is preferred.
  • 28. Aortic Stenosis  Mild stenosis and normal left ventricular systolic function can be managed conservatively.  Moderate to severe stenosis or symptomatic, delay conception until aortic stenosis is corrected.  Pregnant women with severe aortic stenosis who develop symptoms may require either early delivery or percutaneous balloon valvotomy or surgery before delivery.
  • 29. Aortic Regurgitation  Isolated aortic regurgitation can be managed with diuretics and vasodilator therapy.  Surgery during pregnancy only for control of refractory symptoms.
  • 30. Anticoagulation therapy  Low molecular weight heparin (LMWH) and Factor Xa inhibitors should not be used in pregnancy unless Factor Xa activity can be measured  The anticoagulation therapy for patients with mechanical valves is of critically important and should be managed by Cardiologists
  • 31. Anticoagulation: 1st trimester  If warfarin maintenance dose is ≥5 mg/day, risk of teratogenicity is 8-10%. Convert warfarin to subcutaneous unfractionated heparin (UFH) b.d. Maintain APTT 1.5-2X control.  If warfarin dose is <5 mg/day, risk of teratogenicity is 2%. Discuss risks with patient and the options of changing to UFH or continuing warfarin.
  • 32. Anticoagulation: 2nd & 3rd trimester  Use warfarin. Maintain INR 2.0-3.0.  At 36 weeks, admit patient and convert to i.v. UFH. Plan for delivery once INR <1.5.  Stop i.v. UFH 6 hours before delivery and restart 6 hours after delivery if no bleeding.  First dose of warfarin can be given Day 1 post-partum. Stop i.v. heparin once INR >1.8.
  • 33. Shared care:  It’s important to maintain good communication between the Cardiologists/Physicians and the Obstetrician  These patients should be f/up in a combine clinic setting but shared care with health clinics is possible depending on the severity of cases
  • 34. General Advice for MOs 1. If a pregnant woman is suspected or known to have heart disease, she should be referred to a physician or cardiologist as soon as she is found to be pregnant. In the referral letter, request the specialist to state clearly in his/her reply letter: a. The cardiac diagnosis b. Whether the pregnancy is allowed to continue or whether termination is recommended c. The type of antenatal follow up required – polyclinic, district hospital, hospital with specialist or cardiac centre 2. If unsure, always check the drug formulary (MIMS, MOH “blue book”, internet resources, etc) to confirm that whatever medication prescribed is safe to use during pregnancy. 3. The best guide to how well a patient with heart disease is tolerating pregnancy is her functional status. If the patient is asymptomatic and able to do moderate or heavy work without any difficulty, then most likely she will also tolerate the pregnancy. 4. Physical examination should be geared towards looking for signs of heart failure – basal lung crackles, raised JVP, peripheral edema. Multiple repeat echocardiograms usually not necessary as the cardiac lesions are “fixed” and unlikely to change during the course of the pregnancy
  • 35. Think: What can you do to reduce the morbidity and mortality of pregnant mothers with heart diseases?