Echocardiography in Pulmonary Hypertension
Yes, transthoracic Doppler echocardiography should always be performed in patients with suspected or documented pulmonary hypertension as the essential first-line noninvasive screening and diagnostic tool. 1
Primary Screening Role
Doppler echocardiography must be performed as the initial noninvasive screening test in all patients with clinical suspicion of pulmonary arterial hypertension (PAH). 1 This represents a Grade A recommendation with substantial benefit, despite some imprecision in determining actual pressures compared to invasive evaluation. 1
Key Diagnostic Parameters to Assess
Estimate right ventricular systolic pressure (RVSP) using continuous-wave Doppler measurement of peak tricuspid regurgitation velocity, which has 79-100% sensitivity and 68-98% specificity for detecting moderate pulmonary hypertension. 1
Evaluate structural abnormalities including right atrial enlargement, right ventricular enlargement, and pericardial effusion—all critical markers of disease severity and prognosis. 1, 2
Assess right ventricular function through tricuspid annular plane systolic excursion (TAPSE), which provides essential prognostic information. 2, 3
Identifying Underlying Causes
In all patients with suspected or documented PH, echocardiography must be performed to identify secondary causes, particularly left heart disease. 1 This is a Grade A recommendation with substantial benefit. 1
Screen for left ventricular systolic and diastolic dysfunction, left-sided chamber enlargement, and valvular heart disease—the most common causes of pulmonary hypertension in clinical practice. 1
Perform contrast ("bubble") echocardiography to detect intracardiac shunting in patients with suspected or documented PH (Grade B recommendation). 1
Screening High-Risk Asymptomatic Patients
Doppler echocardiography should be performed in asymptomatic patients at high risk for developing PAH. 1 High-risk groups include:
- Patients with known genetic mutations predisposing to PH or first-degree relatives with familial PAH 1
- Patients with scleroderma spectrum disease 1
- Patients with congenital heart disease and systemic-to-pulmonary shunts 1
- Patients with portal hypertension prior to liver transplantation 1
Critical Limitations and Next Steps
Important caveat: Echocardiography cannot replace right heart catheterization for definitive diagnosis. 1, 4
Doppler echocardiography may underestimate systolic pulmonary artery pressure in severe PH and overestimate pressures in populations with mostly normal pressures. 1
Mild, asymptomatic PH is not reliably detected by Doppler echocardiography. 1
Right heart catheterization remains mandatory for confirming PH diagnosis in patients with intermediate or high echocardiographic probability before initiating specific PAH therapy. 1, 4
Additional limitations include acoustic window restrictions (especially in patients with underlying lung disease), body habitus constraints, and operator dependence. 1
Prognostic Value
Echocardiographic findings provide critical prognostic information beyond diagnosis. 2, 3
Mortality risk increases approximately 40% with every 10 mmHg increase in pulmonary artery systolic pressure. 2
Presence of pericardial effusion, reduced TAPSE, and right atrial enlargement are associated with poorer prognosis. 3
Right ventricular function assessed by echocardiography is a critical determinant of outcomes in PAH. 2
Follow-Up Monitoring
Serial echocardiography is essential for monitoring treatment response and disease progression, recommended every 3-6 months after therapy initiation or changes. 4, 3