What is the next best step in management for a 28‑week‑plus pregnant woman presenting with shortness of breath and cardiology follow‑up?

Management of Shortness of Breath in a 28-Week Pregnant Woman with Cardiology Follow-Up

This patient requires immediate comprehensive cardiovascular evaluation with echocardiography and ECG to exclude life-threatening cardiac conditions, as shortness of breath in pregnancy can represent dangerous underlying pathology including mitral stenosis, pulmonary hypertension, peripartum cardiomyopathy, or pulmonary embolism—conditions that carry significant maternal and fetal mortality risk. 1

Immediate Assessment and Risk Stratification

Critical First Steps

• Obtain oxygen saturation immediately and maintain SpO2 >95% with supplemental oxygen as needed, as pregnant patients have lower oxygen reserves and higher metabolic demands 2, 3
• Position the patient in left lateral tilt to optimize venous return and cardiac output 2
• Perform focused cardiovascular examination looking specifically for signs of heart failure (elevated JVP, pulmonary crackles, peripheral edema beyond normal pregnancy), murmurs suggesting valvular disease, and signs of pulmonary hypertension 1

Red Flag Symptoms Requiring Emergency Evaluation

The following symptoms indicate potentially life-threatening conditions and require immediate escalation 4:

• Severe dyspnea at rest (not just exertional)
• Pleuritic chest pain
• Syncope or presyncope
• Hemoptysis
• Palpitations with hypotension

Diagnostic Workup

Essential Cardiac Evaluation

Modern echocardiography along with ECG provides the primary means for completing the clinical diagnosis and should be performed urgently 1. This evaluation must assess:

• Left ventricular systolic and diastolic function
• Valvular pathology (particularly mitral stenosis, which can be missed and wrongly ascribed to pregnancy itself or asthma) 1
• Right ventricular function and pulmonary artery pressures
• Presence of structural abnormalities 1

High-Risk Cardiac Conditions to Exclude

The dangerous conditions that can present with shortness of breath at 28 weeks include 1:

• Pulmonary vascular disease/pulmonary hypertension (carries highest maternal mortality risk)
• Mitral or aortic stenosis (can cause trouble even when previously asymptomatic)
• Peripartum cardiomyopathy (can present in third trimester)
• Left ventricular dysfunction (dilated, poorly functioning ventricles)

Pulmonary Embolism Evaluation

Pulmonary embolism is the leading cause of pregnancy-related maternal death in developed countries, occurring in 1 per 1000 to 1 per 3000 deliveries 2, 4. The diagnostic approach should include:

• Bilateral lower extremity compression ultrasound first—if positive for DVT, this confirms venous thromboembolism and treatment can begin without further imaging 2
• Do NOT rely on D-dimer to exclude PE in pregnancy—it has inadequate sensitivity (73%) and poor specificity (15%) 2
• If DVT ultrasound is negative and clinical suspicion remains high, proceed to CT pulmonary angiography or ventilation-perfusion scan (radiation concerns should not prevent indicated imaging—fetal doses are well below harmful thresholds) 2

Respiratory Causes to Consider

• Asthma exacerbation (obtain peak flow measurements, assess for wheezing)
• Pneumonia (check temperature, auscultate for focal findings)
• Physiologic dyspnea of pregnancy (diagnosis of exclusion after serious pathology ruled out) 2, 4

Management Based on Findings

If Cardiac Disease Identified

Refer immediately to a specialist cardio-obstetrics center for multidisciplinary team management involving experienced cardiologists, obstetricians, maternal-fetal medicine specialists, anaesthetists, and neonatologists 1. Shared care can then be organized with the local hospital.

NYHA Functional Class Assessment

• Any patient reaching NYHA class III or IV is at high risk regardless of underlying condition, as this indicates no remaining cardiovascular reserve 1
• Most patients in NYHA classes I and II will have successful outcomes, but some conditions (mitral stenosis, aortic stenosis) can deteriorate even from asymptomatic states 1

Specific Cardiac Conditions Management

For Mitral Stenosis:

• Medical management with beta-blockers for rate control 1
• Diuretics for pulmonary congestion 1
• In severe symptomatic stenosis not responding to medical therapy and bed rest, percutaneous valvuloplasty can be undertaken during pregnancy 1

For Heart Failure/Cardiomyopathy:

• Close maternal monitoring for heart failure signs by cardiology and obstetric teams 1
• Echocardiography for any significant changes in symptoms during pregnancy 1
• BNP or NT-proBNP monitoring may have value for predicting cardiovascular events 1
• Modified heart failure regimen: continue beta-blocker (metoprolol preferred), hydralazine, and nitrates; adjust diuretics to avoid placental hypoperfusion 1
• ACE inhibitors, ARBs, ARNIs, MRAs, and SGLT2 inhibitors are contraindicated in pregnancy 1

For Pulmonary Hypertension:

• This represents the highest-risk condition in pregnancy 1
• Requires intensive monitoring and early delivery planning
• Multidisciplinary team approach essential for timing and mode of delivery 1

If Pulmonary Embolism Confirmed

• Initiate therapeutic-dose low molecular weight heparin immediately 2
• Continue anticoagulation throughout pregnancy and for at least 6 weeks postpartum 2

If Asthma Exacerbation Identified

Never discontinue asthma medications during pregnancy—poorly controlled asthma causes more fetal harm than the medications 2, 3.

Acute Management:

• Albuterol nebulizer 2.5-5mg every 20 minutes for up to 3 treatments 3
• Consider adding ipratropium bromide 0.5mg to albuterol for severe exacerbations 3
• Maintain oxygen saturation >95% 3

Ongoing Controller Therapy:

• Budesonide is the preferred inhaled corticosteroid with most extensive pregnancy safety data 3
• Dosing: 200-600 mcg daily (low dose), 600-1200 mcg daily (moderate), >1200 mcg daily (high dose) 3

Surveillance and Follow-Up

Frequency of Monitoring

• Monthly or bimonthly cardiac evaluations including echocardiography for patients with significant cardiac disease 1
• Monthly assessment of symptoms and functional status 3
• Routine echocardiographic screening in third trimester for reassessment before labor 1

Delivery Planning

• Do not transport a pregnant patient with cardiac disease for cesarean delivery—management should occur at the site where full resources are available 1
• Mode and timing of delivery should be determined by multidisciplinary team based on maternal cardiac status and fetal well-being 1
• Vaginal delivery is preferred in most cases unless obstetric indications for cesarean exist 1

Critical Pitfalls to Avoid

• Never attribute shortness of breath to "normal pregnancy" without excluding serious cardiac and pulmonary pathology first—mitral stenosis and pulmonary hypertension are commonly missed because symptoms are wrongly ascribed to pregnancy 1
• Do not rely on D-dimer to exclude pulmonary embolism in pregnancy 2
• Never discontinue cardiac or asthma medications due to pregnancy concerns—uncontrolled disease poses far greater fetal risk than medications 1, 3
• Maintain vigilance for 24-48 hours postpartum, as this represents a second critical high-risk window for cardiorespiratory decompensation 2, 3
• Do not delay indicated imaging studies due to radiation concerns—fetal radiation doses from chest X-ray and CT are well below harmful thresholds 2