What are the next steps for a patient with elevated Right Ventricular Systolic Pressure (RVSP) on echocardiogram (echo) suggestive of severe Pulmonary Hypertension (PH)?

Next Steps for Elevated RVSP Suggestive of Severe Pulmonary Hypertension

Proceed immediately to right heart catheterization (RHC) for definitive diagnosis, as echocardiography alone cannot confirm pulmonary arterial hypertension or guide treatment decisions. 1, 2

Immediate Diagnostic Workup

Confirm Need for Right Heart Catheterization

• An RVSP >40 mmHg warrants further evaluation in patients with unexplained dyspnea, and severe elevation (≥60 mmHg or tricuspid regurgitation velocity >3.4 m/s) indicates high probability of PH requiring RHC. 1, 2
• RHC is the gold standard and mandatory for confirming PH diagnosis before initiating any PAH-specific therapy. 2, 3
• Echocardiography may underestimate pulmonary artery pressure by a mean of 11 mmHg, with underestimation of ≥20 mmHg in up to 31% of patients. 4
• In 10% of patients with invasively confirmed PH, tricuspid regurgitation may be absent or inadequate for RVSP estimation, potentially missing the diagnosis. 3

Comprehensive Evaluation Before RHC

Complete the following tests to identify underlying etiology and assess disease severity: 1, 2

Laboratory studies:

• Complete blood count, comprehensive metabolic panel, liver function tests 1
• Thyroid function testing 1
• N-terminal pro-BNP (NT-proBNP) for prognostic assessment 1
• HIV serology 1
• Antinuclear antibody (ANA); if positive, obtain full autoimmune panel including anti-Scl-70, anti-centromere, anti-RNP, anti-SSA, anti-SSB 1
• Hepatitis serologies 1
• Hypercoagulable panel if clinically indicated 1

Imaging and functional studies:

• Chest X-ray and electrocardiogram to identify coexistent cardiopulmonary disease 1
• Pulmonary function tests with diffusing capacity to assess for underlying lung disease 1, 2
• Ventilation/perfusion (V/Q) scan as the preferred screening method for chronic thromboembolic pulmonary hypertension (CTEPH) due to higher sensitivity 1, 2
• High-resolution CT chest (non-contrast or CT angiogram if thromboembolic disease suspected) to evaluate parenchymal lung disease 1, 2
• Six-minute walk test to establish baseline functional capacity 1, 2
• Sleep study evaluation for sleep-disordered breathing 1, 2

Enhanced echocardiographic assessment:

• Review for additional signs of PH beyond RVSP: right atrial enlargement, right ventricular enlargement, interventricular septal flattening, dilated inferior vena cava (>21 mm with decreased inspiratory collapse), pulmonary artery diameter >25 mm 1
• If tricuspid regurgitation signal is weak, enhance with intravenous agitated saline contrast or encapsulated microbubble contrast agents (use cautiously in severe pulmonary vascular disease) 1, 4
• Assess for left heart disease, valvular abnormalities, or congenital heart disease that may contribute to PH 1, 2
• If intracardiac shunt suspected (history of childhood murmurs, cyanosis, clubbing), perform bubble study; consider transesophageal echocardiography if sinus venosus defect or anomalous pulmonary venous return suspected 1

Right Heart Catheterization Protocol

RHC provides definitive hemodynamic diagnosis and guides treatment decisions: 2

• Confirm PH: mean pulmonary artery pressure >20 mmHg (updated threshold from previous ≥25 mmHg) 1
• Distinguish PAH from other PH types: pulmonary artery wedge pressure ≤15 mmHg and pulmonary vascular resistance ≥3 Wood units for PAH diagnosis 1, 2
• Perform vasoreactivity testing during catheterization to identify patients who may respond to calcium channel blockers 2
• Assess cardiac output and pulmonary vascular resistance to determine disease severity and prognosis 2, 5

Common Pitfalls to Avoid

• Do not initiate PAH-specific therapies based on echocardiography alone, as treatment decisions require hemodynamic confirmation by RHC. 1, 4
• Do not rely solely on RVSP value; approximately 10-25% of PH patients have insufficient tricuspid regurgitation for accurate measurement. 1, 3
• Do not use exercise echocardiography findings to make treatment decisions, as no consensus exists for exercise-induced PH management. 1, 4
• Do not overlook severe tricuspid regurgitation, which may significantly underestimate TRV and cannot exclude PH. 1
• Do not skip V/Q scanning; it remains superior to CT angiography for CTEPH screening despite advances in CT technology. 1

Risk Stratification and Prognosis

• Elevated RVSP correlates with poor outcomes, with mortality risk increasing approximately 40% for every 10 mmHg increase in pulmonary artery systolic pressure. 2
• Right ventricular function is a critical determinant of outcomes and should be carefully assessed during diagnostic workup. 2
• Patients with confirmed PAH have 67% three-year survival despite modern therapies, emphasizing the importance of early diagnosis and specialist referral. 1

Specialist Referral

Refer to a pulmonary hypertension specialist immediately for patients with confirmed severe PH on echocardiography, as management requires expertise in hemodynamic assessment, vasoreactivity testing, and PAH-specific therapies. 1, 2