291.1 🎓 醫孞生版

291.1.0.1 📌 䞀頁重點

291.1.0.1.1 Pregnancy CV Physiology
291.1.0.1.1.1 Hemodynamic Changes
  • Plasma volume ↑ 40-50% (peak 28-32 weeks)
  • Red cell mass ↑ 20-30% → “physiologic anemia of pregnancy” (dilutional)
  • Cardiac output ↑ 30-50% (HR ↑ 10-20 + SV ↑)
  • Heart rate ↑ 10-20 bpm
  • SVR ↓ 20% (progesterone, vasodilation, placental shunt)
  • SBP ↓ slightly mid-pregnancy, returns to baseline near term
  • DBP ↓ 5-10 mmHg mid-pregnancy
  • Pulmonary capillary wedge unchanged or slightly elevated
291.1.0.1.1.2 Timing of Peak Stress
  • 28-32 weeks: maximal blood volume + CO
  • Labor & delivery: massive hemodynamic swings (CO ↑ 30-50% with each contraction)
  • Immediate postpartum (1-2 weeks): “auto-transfusion” + diuresis → also high risk
291.1.0.1.1.3 ECG Changes in Pregnancy
  • Sinus tachycardia
  • Mild Q in lead III (rotation)
  • T wave inversions (positional)
  • Premature beats common
291.1.0.1.1.4 CV Symptoms vs Disease (Distinguishing)
  • Dyspnea, fatigue, peripheral edema: usually physiologic
  • Pre-syncope: can be normal
  • Pathologic: dyspnea at rest, orthopnea, paroxysmal nocturnal dyspnea, hemoptysis, chest pain at rest, syncope
291.1.0.1.2 Risk Stratification — mWHO
291.1.0.1.2.1 Modified WHO Classification
Class Risk Examples
I No increase Uncomplicated, repaired/small CHD; mitral valve prolapse without sig MR; pulmonic stenosis mild; SVT
II Small increase Unrepaired ASD/VSD; repaired TOF; SVT untreated
II-III Intermediate Mild LV impairment; HCM; mod MS; native or tissue valve; uncomplicated coarctation; Marfan without aortic dilation; aorta < 45 mm
III Significantly increased Moderate LV dysfunction; previous PPCM without LV recovery; mechanical valve (anticoag risk!); systemic RV; Fontan; cyanotic CHD; complex valve disease; Marfan with aorta 40-45 mm
IV AVOID PREGNANCY Pulmonary HTN (any cause); Eisenmenger; severe PAH; severe systemic LV dysfunction (EF < 30%); previous PPCM with persistent LV dysfunction; severe MS; severe symptomatic AS; native severe AS regardless of symptoms; coarctation severe; Marfan with aorta > 45 mm; aortic dilation > 50 mm with BAV
291.1.0.1.3 Pre-Pregnancy Counseling
  • Risk assessment with mWHO
  • Maternal + fetal risk discussion
  • Optimize cardiac status BEFORE pregnancy
  • Medication review (substitute teratogens)
  • Genetic counseling for heritable CHD
  • Vaccinations (flu, pneumococcal, COVID, RSV, Tdap)
  • Contraception options:
    • Avoid combined OCP in many CV diseases (clotting risk)
    • LARC (IUD, implant) preferred
    • Barrier methods
    • Sterilization in mWHO IV
291.1.0.1.4 Pregnancy-Associated CV Conditions
291.1.0.1.4.1 Preeclampsia / Eclampsia
  • Hypertensive disorder after 20 weeks gestation
  • Definition: BP ≥ 140/90 + proteinuria (or end-organ damage)
  • Severe: SBP ≥ 160 or DBP ≥ 110 + symptoms (HA, vision changes, RUQ pain, low platelets, AKI, LFTs)
  • Eclampsia: seizures
  • HELLP: Hemolysis, ↑ LFT, ↓ Platelets
  • Risk factors: 1st pregnancy, age extremes, obesity, DM, multiple gestation, prior preeclampsia, autoimmune (APS, SLE)
  • Treatment:
    • Magnesium sulfate for seizure prophylaxis (4-6 g IV → 1-2 g/h)
    • BP control: labetalol IV / nifedipine PO / hydralazine IV (target SBP < 160, DBP < 110)
    • Delivery is definitive
  • Future CV risk: 2-4x ↑ for CVD later in life
291.1.0.1.4.2 Peripartum Cardiomyopathy (PPCM)
  • Definition: HF developing late pregnancy (last month) to 5 months postpartum
  • Normal heart pre-pregnancy, LVEF < 45%
  • Incidence: 1 in 1,000-4,000 deliveries
  • Risk factors: African American (4-10x higher), multiparity, age > 30, multiple gestation, HTN, preeclampsia
  • Pathophysiology: prolactin fragment + sFlt-1 + angiogenic imbalance → endothelial injury, myocyte damage
  • Treatment:
    • Standard HF therapy + adjustments for pregnancy/postpartum:
      • Loop diuretics (PO/IV; avoid spironolactone/eplerenone during pregnancy)
      • β-blocker (carvedilol, bisoprolol post-delivery; metoprolol during)
      • Hydralazine + isosorbide nitrate (instead of ACEi/ARB during pregnancy)
      • Post-delivery: ACEi/ARB safe
      • Bromocriptine (prolactin inhibitor): controversial; some trials show benefit (BOARDER 2017, Hilfiker-Kleiner)
    • Anticoagulation: LV thrombus risk, especially if EF < 35% — LMWH/UFH first trimester, warfarin OK 2nd-3rd
    • Cardiac MRI for LV function, fibrosis
  • Outcomes: 50% recover LV function; 50% don’t; mortality 6-25%
  • Future pregnancy: contraindicated if persistent LV dysfunction; possible if full recovery (still risk of recurrence 30-50%)
291.1.0.1.4.3 Aortic Dissection
  • Pregnancy ↑ risk (estrogen, ↑ CO, hormone-related aortic wall changes)
  • Marfan, BAV, vEDS, prior dissection
  • Aortic dilation > 4.5 mm risk
  • 50% in 3rd trimester / postpartum
  • Treatment: same as non-pregnant (esmolol, surgery)
  • Prevent: pre-pregnancy aortic repair if root > 4.5 mm + Marfan
291.1.0.1.4.4 Spontaneous Coronary Artery Dissection (SCAD)
  • 1-4% of all MI in pregnancy
  • Most often peripartum / postpartum
  • LAD / circumflex common
  • Conservative management preferred (do NOT routinely PCI; high re-dissection risk)
  • Avoid stress testing during recovery
  • AC/AP cautious
291.1.0.1.4.5 Pulmonary Embolism
  • Pregnancy 5-10x ↑ risk for VTE
  • Treatment: LMWH preferred (no placental crossing); switch to UFH around delivery
  • DOACs NOT used in pregnancy
  • 6-week postpartum extension at minimum
291.1.0.1.4.6 Mechanical Valve Thrombosis
  • Pregnancy → highest risk during 1st trimester or post-warfarin switch
  • Warfarin teratogenic 1st trimester → LMWH (weight-adjusted) often used
  • Strict anti-Xa monitoring
  • Some protocols: warfarin in 2nd-3rd trimester then LMWH near delivery
  • High-risk: bridge to delivery
291.1.0.1.4.7 Arrhythmias in Pregnancy
  • SVT, PVC, AF can occur (LA stretch)
  • VT possible (esp with structural heart disease)
  • Treatment:
    • Vagal maneuvers + adenosine (SVT)
    • β-blocker (metoprolol) — first-line in pregnancy
    • Digoxin safe
    • Amiodarone AVOID (fetal thyroid, neurologic)
    • Cardioversion safe in unstable
    • Ablation deferred if possible; lead-shielded if needed
291.1.0.1.4.8 Valvular Heart Disease in Pregnancy
  • MS (rheumatic): poorly tolerated; LA dilation + AF + pulmonary edema
    • β-blocker for HR control
    • PMBV during pregnancy if severe symptoms (Wilkins ≀ 8)
  • AS (severe): poorly tolerated; pre-load dependent
    • Avoid pregnancy if severe / symptomatic
    • Avoid spinal/epidural (sudden afterload drop)
  • MR / AR: usually well-tolerated (afterload drop helps)
  • Bicuspid AV + aortic root: monitor with echo
291.1.0.1.4.9 Cyanotic CHD
  • Maternal hypoxia → fetal IUGR, miscarriage
  • Polycythemia + paradoxical embolism risks
  • IV filter for paradoxical embolism prevention
291.1.0.1.4.10 Pulmonary HTN
  • Maternal mortality 30-50% (any PAH; Eisenmenger highest)
  • Absolute contraindication to pregnancy (mWHO IV)
  • If pregnant: multidisciplinary; high mortality
  • Therapeutic abortion offered
  • Sotatercept, bosentan teratogenic — switch agents
291.1.0.1.5 Medications in Pregnancy
291.1.0.1.5.1 Safe / First-Line
  • β-blocker: labetalol, metoprolol (avoid atenolol — IUGR)
  • Methyldopa (HTN, especially mild)
  • Nifedipine ER (HTN, tocolysis)
  • Hydralazine (acute HTN, chronic add-on)
  • Digoxin (rate control)
  • Adenosine (SVT)
  • LMWH (anticoagulation)
  • Aspirin low-dose (preeclampsia prevention in high-risk)
  • Diuretics: loop diuretics OK if needed; avoid spironolactone
291.1.0.1.5.2 Contraindicated / Avoid
  • ACEi / ARB: fetal renal failure, oligohydramnios; teratogenic (esp 2nd-3rd trimester)
  • MRA (spironolactone, eplerenone): anti-androgen effects on fetus
  • Aliskiren: direct renin inhibitor — contraindicated
  • Warfarin 1st trimester: warfarin embryopathy (chondrodysplasia, nasal hypoplasia); use LMWH bridge
  • DOAC (apixaban, rivaroxaban, edoxaban, dabigatran): cross placenta — avoid
  • Statins: AVOID (CDC reversal 2021 — some say possibly OK in select; controversy)
  • Atenolol: IUGR risk
  • Amiodarone: fetal thyroid, neurologic
  • ETRs (bosentan, ambrisentan, macitentan): teratogenic — REMS program
  • Riociguat: contraindicated
  • Sotatercept: avoid
291.1.0.1.5.3 Antibiotics
  • Endocarditis prophylaxis: amoxicillin OK; if penicillin allergic, clindamycin OK
  • Avoid: tetracyclines (tooth, bone), fluoroquinolones (cartilage)
291.1.0.1.6 Labor and Delivery Considerations
291.1.0.1.6.1 General Principles
  • Vaginal delivery preferred for most cardiac patients (less hemodynamic stress)
  • Cesarean for obstetric indications or specific cardiac (aortic dissection risk, Marfan with severe dilation, severe pulmonary HTN)
  • Multidisciplinary planning: OB, cardiology, anesthesia, neonatology
  • Early epidural to reduce pain-induced catecholamine surge
291.1.0.1.6.2 Specific
  • Eisenmenger: cesarean elective at 32-34 weeks for maternal optimization; high mortality
  • Mechanical valve: AC management around delivery (UFH preferred peripartum)
  • AS severe: avoid hypotension; spinal/epidural carefully
  • Marfan: epidural OK; consider cesarean if aorta > 4.0-4.5 mm
  • PPCM: full HF management
291.1.0.1.6.3 Postpartum
  • 2-week + 6-week highest CV risk peripartum
  • Re-introduce ACEi/ARB after delivery (lactation OK for most)
  • Anticoagulation continuation
  • Cardiology follow-up

291.1.0.2 🩺 床邊速查

  • Pregnancy physiology: blood volume ↑ 40-50%, CO ↑ 30-50%, SVR ↓ 20%; peak stress 28-32 wk + L&D + first 2 wk postpartum
  • mWHO 4 (避孕): Eisenmenger, severe PAH, severe AS, single vent, Marfan aorta > 45 mm, EF < 30%, severe MS
  • PPCM: HF in last month preg to 5 mo postpartum; bromocriptine controversial; LMWH if EF < 35%
  • Hypertensive disorders: preeclampsia → magnesium for seizure prophylaxis; labetalol/nifedipine/hydralazine for BP; delivery definitive
  • Anticoag in mechanical valve: LMWH 1st trimester → warfarin 2nd-3rd → UFH/LMWH around delivery
  • Avoid: ACEi/ARB/MRA/aliskiren/atenolol/amiodarone/statins/ETAs/DOAC/warfarin 1st trimester