Should a 28‑week pregnant patient with known heart disease be admitted to the hospital?

Hospital Admission at 28 Weeks for Pregnant Patients with Known Heart Disease

Admission at 28 weeks gestation should be individualized based on specific cardiac risk factors, but is generally NOT routinely indicated for all pregnant women with heart disease; instead, admission is reserved for those with high-risk features including NYHA class III-IV symptoms, severe valvular stenosis, pulmonary hypertension, cyanosis, or signs of decompensation. 1

Risk-Based Admission Criteria

Mandatory Admission Indications at 28 Weeks

The following conditions warrant hospital admission at or around 28 weeks gestation:

• NYHA functional class III-IV symptoms – These patients have no cardiovascular reserve and are at extremely high risk for decompensation during the peak hemodynamic stress period of 24-32 weeks. 1, 2

• Severe pulmonary hypertension – Maternal mortality risk reaches 30-50%, making close inpatient monitoring essential during the critical second-to-third trimester transition. 2

• Cyanotic heart disease with oxygen saturation <85% – Fetal growth monitoring becomes critical as growth typically slows and ceases before term in cyanosed women. 1

• Severe aortic stenosis (mean gradient ≥40 mmHg) with symptoms – The fixed obstruction cannot accommodate the 30-50% increase in cardiac output, risking acute hemodynamic collapse. 1, 2

• Severe mitral stenosis (valve area <1.0 cm²) with persistent symptoms despite medical therapy – The stenotic valve cannot accommodate increased stroke volume, causing sharp rises in transvalvular gradient and precipitating pulmonary edema. 3

• Aortic root diameter >4.5 cm in Marfan syndrome or >45 mm in other aortopathies – Risk of aortic dissection is 10% during pregnancy in these patients. 1

Outpatient Management with Frequent Monitoring

Lower-risk patients can be managed as outpatients with intensified surveillance:

• NYHA class I-II with well-controlled cardiac disease – These patients can be followed with monthly or bimonthly clinical and echocardiographic assessments. 4

• Mild-to-moderate valvular disease without symptoms – Close outpatient monitoring every 2-4 weeks during the peak hemodynamic period (24-32 weeks) is appropriate. 4

• Repaired congenital heart disease with good functional status – Outpatient management with regular cardiology follow-up is reasonable. 1

Critical Timing Considerations

The 28-week timepoint falls within the highest-risk hemodynamic window (24-32 weeks gestation) when cardiac output peaks at 40-50% above baseline and plasma volume reaches maximum expansion. 1, 2, 3

• Between 28-32 weeks represents a particularly difficult decision period where fetal viability improves dramatically (neonatal survival rises from <75% before 28 weeks to 95% after 32 weeks), but maternal cardiac stress remains maximal. 1

• Before 28 weeks, neonatal survival is low (<75%) with high risk of brain damage (10-14%), so cardiac interventions or procedures should be undertaken to postpone delivery if feasible rather than proceeding with early delivery. 1

Multidisciplinary Team Requirements

All high-risk pregnant cardiac patients require management by a specialized pregnancy heart team at a tertiary care center, regardless of admission status. 1, 2

This team must include:

• Cardiologists with expertise in pregnancy
• Maternal-fetal medicine specialists
• Cardiac anesthesiologists
• Cardiothoracic surgeons (available for emergencies)
• Neonatologists 1, 4

Common Pitfalls to Avoid

• Do not delay admission until overt decompensation occurs – Heart failure develops rapidly during the 24-32 week period, and 66% of serious cardiac events occur in the antepartum period. 5, 6

• Do not attribute new dyspnea or edema solely to "normal pregnancy changes" – These may represent early cardiac decompensation requiring urgent intervention. 4

• Do not continue ACE inhibitors or ARBs – These must be discontinued immediately due to fetal renal toxicity and teratogenicity. 1, 3

• Recognize that approximately 49% of serious cardiac events in pregnancy are preventable, with most preventable events (74%) secondary to provider management factors rather than disease progression. 6

Monitoring Protocol for Admitted Patients

For patients admitted at 28 weeks with high-risk cardiac disease:

• Daily clinical assessment for signs of heart failure (orthopnea, paroxysmal nocturnal dyspnea, peripheral edema, rales). 1

• Serial echocardiography every 4-8 weeks for those with aortic dilatation or every 2-4 weeks for severe mitral stenosis. 4

• Continuous fetal monitoring in cyanotic patients, as fetal growth typically slows and ceases before term. 1

• Optimization of medical therapy with beta-blockers for rate control in mitral stenosis and cautious diuretics for pulmonary congestion. 3