What are the symptoms and diagnostic criteria to suspect pulmonary hypertension?

How to Suspect Pulmonary Hypertension

Clinical Presentation That Should Trigger Suspicion

Suspect pulmonary hypertension in any patient with unexplained breathlessness without overt signs of specific heart or lung disease, or when dyspnea is disproportionate to the severity of known underlying cardiac or pulmonary conditions. 1

Cardinal Symptoms

• Dyspnea on exertion is the most common presenting symptom and warrants evaluation when it occurs without clear explanation from existing heart or lung disease 1, 2
• Syncope, particularly with exertion, is a critical warning sign indicating severely compromised cardiac output and demands urgent referral 2
• Rapidly progressive symptoms including fatigue, weakness, angina, and abdominal distension should prompt immediate cardiology or respiratory evaluation 1, 2
• Symptoms at rest indicate very advanced disease and represent a late, ominous finding 1, 2

Physical Examination Findings

The following physical signs require clinical experience to appreciate but are highly suggestive of pulmonary hypertension: 1

• Accentuated pulmonary component of S2 (loud P2) is the most consistently associated sign with PAH, though sensitivity is only 55-70% 1, 2
• Left parasternal lift (right ventricular heave) indicating right ventricular hypertrophy and pressure overload 1, 2
• Pansystolic murmur of tricuspid regurgitation reflecting elevated right ventricular pressures 1, 2
• Diastolic murmur of pulmonary insufficiency from pulmonary valve incompetence 1, 2
• Right ventricular S3 gallop 1

Signs of Advanced Disease with Right Ventricular Failure

• Jugular vein distension with prominent V waves 1
• Hepatomegaly (often pulsatile) 1
• Peripheral edema 1
• Ascites 1
• Cool extremities from low cardiac output 1
• Central cyanosis (and sometimes peripheral cyanosis) 1
• Lung sounds are usually normal, which is an important distinguishing feature 1

High-Risk Populations Requiring Heightened Suspicion

Clinical suspicion should be particularly elevated when symptoms and signs occur in patients with the following predisposing conditions: 1

• Connective tissue diseases (CTD) 1, 2
• Portal hypertension 1, 2
• HIV infection 1, 2
• Congenital heart diseases with systemic-to-pulmonary shunts 1, 2
• Family history of pulmonary hypertension 2
• History of drugs and toxins associated with PH (particularly anorexigens) 1
• Chronic thromboembolic disease 1

In patients with these predisposing conditions, periodic screening assessments are supported even when asymptomatic to identify early-stage PH. 1, 2

Initial Diagnostic Investigations

Chest Radiograph

Chest radiography is often the first imaging test performed and is appropriate in initial evaluation, though a normal chest X-ray does not exclude PH. 1

• Central pulmonary arterial dilatation with rapid tapering ("pruning") of peripheral vessels 1
• Right interlobar artery >15 mm in women (>16 mm in men) at the hilum is suggestive 1
• Right atrial and ventricular enlargement 1
• Abnormal in 90% of IPAH patients at diagnosis, but insensitive for mild PH 1

Electrocardiogram

ECG may provide suggestive evidence but has inadequate sensitivity (55%) and specificity (70%) to serve as a screening tool. 1

• Right ventricular hypertrophy (present in 87% of IPAH patients) 1
• Right axis deviation (present in 79% of IPAH patients) 1
• Right atrial dilation 1
• A normal ECG does not exclude severe PH 1

Transthoracic Doppler Echocardiography

Transthoracic Doppler echocardiography should always be performed when PH is suspected and has sensitivity of 79-100% and specificity of 68-98% for detecting moderate PH. 1, 2

• Continuous-wave Doppler measurement of peak tricuspid regurgitation velocity is the primary screening parameter 1
• Additional parameters include right and left ventricular dimensions and function, valve abnormalities, and pericardial effusion 1
• Detection of mild PH is more limited with echocardiography 1
• False negative results are possible, so maintain high clinical suspicion despite negative findings 1

Critical Pitfall to Avoid

PH can be suspected when abnormal electrocardiographic, chest radiograph, or echocardiographic findings are detected incidentally during procedures performed for other clinical reasons. 1 Do not dismiss these findings even in the absence of classic symptoms, as patients may not report or recognize early symptoms.

When to Refer Urgently

Immediate referral to cardiology/respiratory or a PH center is indicated for: 2

• Syncope, especially with exertion
• Rapidly progressing symptoms
• Signs of right heart failure at rest
• Clinical or echocardiographic signs of severe PH and/or severe right ventricular dysfunction