RF & RHD Workshop 22 nd March 2016 MANAGEMENT of RHEUMATIC HEART DISEASE in PREGNANCY Dr Dorothy Radford
PREGNANCY PHYSIOLOGY Increased cardiac output 30%-50% Increased blood volume 30%-50% Increased heart rate 10-20 bpm at rest Increased red cell mass 20-30% Relative anaemia Decreased vascular resistance Decreased blood pressure
LABOUR & DELIVERY Uterine contractions cause an extra 300 to 500 mls of blood to enter circulation Increased BP Increased HR Increased CO (at delivery, up to 80% above pre-pregnancy level)
CLINICAL FINDINGS IN PREGNANCY Hyperdynamic circulation Systolic murmur > 90% Third heart sound > 80% Venous hum Mammary souffle Diastolic murmur of severe mitral stenosis can be missed.
PREGNANCY IN RHEUMATIC HEART DISEASE Circulatory load will exacerbate existing problems. Need to discuss and plan ahead with young women. Contraceptive advice. Appropriate intervention before pregnancy.
RISK FACTORS Predictors of increased maternal & foetal risk Stenotic lesions Mitral & Aortic stenosis (Regurgitant lesions better tolerated) Pulmonary hypertension Reduced LV function History of heart failure Symptoms before pregnancy Atrial fibrillation Mechanical valve- warfarin
PREGNANCY SCAN FOETAL ULTRASOUND ECHOCARDIOGRAM
MITRAL STENOSIS
MITRAL STENOSIS
RHEUMATIC MITRAL VALVE For MITRAL STENOSIS intervene when Symptomatic - dyspnoea Mitral Valve Area < 1.5 cm2 Pulmonary Artery Pressure > 50 mmshg
BALLOON MITRAL VALVOTOMY
SEVERE CALCIFIC MITRAL STENOSIS
AORTIC STENOSIS
AORTIC INCOMPETENCE
RHEUMATIC AORTIC INCOMPETENCE Indications for Surgery Symptoms LVEDD > 70 mms LVESD > 55 mms LVEF < 55%
RHEUMATIC MITRAL STENOSIS AND INCOMPETENCE Long axis view of MV. Patient QW of Mornington Is
Four chamber view of Mitral valve with Stenosis & Incompetence Patient QW
Four chamber colour Doppler view of Mitral valve Patient QW
MITRAL REGURGITATION - INDICATIONS FOR SURGERY SYMPTOMS ECHO- Reduced EF >60% Dilated LV LVESD >40mms PHT PAS > 50 mms Hg OPERATION of choice MV repair MVR if calcified leaflets etc Avoid mechanical MVR if likely future pregnancy or concern about warfarin adherence
Pre-op view of Mitral valve by 3D echo Patient QW
MITRAL VALVE REPAIR WITH ANNULOPLASTY RING
TISSUE MITRAL VALVE REPLACEMENT
MECHANICAL MITRAL VALVE REPLACEMENT
PREGNANCY & RHEUMATIC HEART DISEASE Stenotic lesions MS / AS a concern Regurgitant lesions are tolerated Reduced LV function/ prior heart failure/ symptomatic valve disease Prosthetic heart valves / Anticoagulants
PROSTHETIC VALVES BIOPROSTHETIC No anticoagulants Valve deterioration Re-operation risk MECHANICAL Require anticoagulant Risk to mother & foetus
TISSUE VALVES PIG COW HUMAN Porcine xenograft Bovine pericardial valve Homograft or Allograft
DOUBLE JEOPARDY ANTICOAGULATION in PREGNANCY WARFARIN Crosses the placenta embryopathy risk of miscarriage risk of foetal bleed neonatal cerebral haemorrhage HEPARIN Does not cross the placenta thrombocytopaenia osteoporosis alopecia risk of valve thrombosis
WARFARIN EMBRYOPATHY COAGUCHECK Nasal hypoplasia Stippled epiphyses Short fingers & neck Low birth weight Careful control of INR is essential Dose < 5mg warfarin daily is unlikely to cause embryopathy
ANTICOAGULANTS PREGNANCY IS A HYPERCOAGUABLE STATE Warfarin gives effective protection Higher risk with higher dose Need to change to heparin 2-4 weeks before delivery (Risk of fetal brain haemorrhage in birth canal) Heparin seems to offer inferior protection Fetal loss from placental haemorrhage Need frequent self injections Need stringent monitoring Increasing dose requirement
DRUGS in PREGNANCY Category A No known foetal risk B - No known human risk. Animal study + C - Pharmacological effect may harm D - Incidence of foetal malformations X - High risk of foetal damage Prescribing medicines in Pregnancy 4 th Edition 1999 Australian categorisation Therapeutic Goods Administration. Web
ARRHYTHMIAS IN PREGNANCY Pregnancy is arrhythmogenic Cardioversion can be used safely Antiarrhythmic drugs Adenosine B Digoxin A Flecainide B Beta-blockers C Verapamil C Amiodarone C
C.C.F. THERAPY in PREGNANCY Digoxin A Diuretics C Beta-blockers C ACE inhibitors D (Can cause in utero foetal death, neonatal anaemia & renal failure) N.B. Natural vasodilatation in pregnancy
INDICATIONS for CAESARIAN SECTION Obstetric reasons Obstructive lesions Pulmonary hypertension Anticoagulation with warfarin (failure to switch to heparin)
Endocarditis Prophylaxis at Delivery RECOMMENDED In the setting of possible bacteraemia Ampicillin + Gentamycin