CONGENITAL HEART DISEASE IN PREGNANCY


I. General principles

  1. If mild or non-cyanotic, us. no probs with preg
  2. IUGR is common, esp. with cyanotic HD
  3. Maternal mortality: Marfan's 50%, Eisenmenger's 30-35%, uncorr. Tet 10-15%, coarc 10%
  4. Death us. from CHF, SBE (with septal defects/PDA), aortic dissection/rupture (with coarc)
  5. Other lesions us. ok unless limited "cardiac reserve"
  6. Preg. safer if defect has been surgically corrected
  7. Try for vag delivery except with severe coarc (risk of rupture)

II. ASD

  1. Most common congenital lesion seen in preg
  2. Usually asymptomatic and without complication in or out of preg
  3. Arrythmias (Afib, rarely SVT/AFlutter)--tx'd c dig, propanolol, quinidine, cardioversion
  4. Characterized by increased pulm flow but nl PA pressure
  5. Sometimes hypervolemia causes strain on RV from more l-r shunt
  6. In labor: lat recumb, O2, good anesthesia, fluid restriction, SBE prophyl

III. VSD

  1. Us. no prob in preg, l & d if small and/or uncomplicated
  2. If big can cause: CHF, arrhyths, PULM HTN (Einsenmenger's!!)
  3. In labor: same as ASD. Invasive hemodynamic monitoring unnecessary
  4. May be associated with tetralogy, xposition of greats, coarc

III. Eisenmenger's syndrome

  1. Reversal or bidirectionality of cong l-r shunt due to PULM HTN
  2. Seen with VSD and PDA; rarely, with ASD
  3. Grave prognosis (matmort 30-50%)--the fear is of crash, as follows:
  1. During pregnancy, fall in SVR causes shunt reversal
  2. Acute fall in systemic BP (hemorrhage, anesthesia, etc) precipitates
  3. Sudden fall in pulm perf press, leading to
  4. Profound sytemic hypoxia and possibly SUDDEN DEATH
  1. So, try to avoid anything causing hypotension in these patients
  2. Risk reverts to nonpreg 4-6wk pp
  3. Thromboemboli assoc'd c 45% matmort, but prophylactic anticoagulation also risky
  4. 30% IUGR rate (from chronic hypoxia?); overall fetal wastage 75%
  5. Management:
  1. If pt won't have Ab, hospitalize for duration of preg,
  2. Continuous O2 (pulm vasodilator)
  3. Labor:monitor with S-G, ABGs
  4. Goal is to avoid hypotn, so keep them on the wet side
  5. Avoid hypotensive anesthesia, e.g. conduction; epidural good
  6. During contractions, pulm/systemic flow decreases
  7. Delivery: c/s matmort is 75%!

IV. PDA

  1. Very common, but usually repaired in infancy
  2. Us. no prob in preg, l & d if corrected
  3. If large and uncorrected can get PULM HTN from l-r shunt--BAD

V. Coarctation of the aorta

  1. 9% of cong HD
  2. Us. no prob if uncomplicated, but
  3. If uncorrected and uncompl, 3-4% matmort
  4. Often ass'd c other aortic/heart abns: VSD, PDA, COW aneurysms
  5. If so, or if NYHA III/IV, matmort approaches 17%
  6. Mort is from CHF but also from rupture/dissection
  7. Primips are at greatest risk

VI. Tetralogy of Fallot

  1. Cyanotic: = VSD, overriding aorta, pulm sten, RVH
  2. Us. no prob in preg, l & d if corrected in childhood (most cases)
  3. If uncorrected, 4-15% matmort; fetmort 30% (hypoxia)
  4. Similar process to Eisenmenger's--low BP, r-l shunt,
  5. Can get real hypoxic from sudden fall in systemic BP
  6. Poor prog ass'd c HCT > 65%, h/o syncope, CHF, cmegaly

VII. Pulmonary stenosis

  1. Common
  2. Degree of obstruction (>80mmHg gradient), rather than location, indicates surgery
  3. Us. no prob in preg; can get mild r-sided HF

VIII. Marfan syndrome

  1. Associated with increased maternal mortality-5% with abnormal aortic valve or dilated aorta (>40mm)
  2. Management: Assess by echocardiogram for aortic root diameter and aortic valve function
  3. In labor, control cardiac output by low exertion (beta-blockers sometimes used?)