Diagnostic Pathways and Risk-Based Monitoring in Pulmonary Hypertension
May 26th, 2026
Pulmonary hypertension (PH) is a progressive condition that increases pressure in the pulmonary arteries, placing strain on the right side of the heart and limiting exercise capacity. To manage this complex condition, early diagnosis and accurate classification of PH subgroups are essential to ensure the timely initiation of treatment and improve patient outcomes. Ongoing and regular monitoring is equally important to track disease progression, guide therapy, and identify signs of deterioration.
This blog outlines how PH is diagnosed, the key investigations used to differentiate between subgroups, and the strategies used to monitor patients over time. It also highlights the importance of a structured, systematic approach and risk-based follow-up in optimising patient care.
Initial Assessment and Referral
The initial assessment of patients usually begins in primary care with a detailed medical history, a physical examination, and the measurement of vital signs such as blood pressure, heart rate, and oxygen saturation. Early investigations may also include blood biomarkers such as brain natriuretic peptide (BNP) or N-terminal pro-brain natriuretic peptide (NT-proBNP) to assess myocardial stress, alongside a resting electrocardiogram (ECG) to identify arrhythmias or structural abnormalities [1]. The most common presenting symptom of PH is exertional dyspnoea, but other symptoms may include fatigue, syncope, peripheral oedema, or jugular venous distension.
If this assessment indicates pulmonary arterial hypertension (PAH), chronic thromboembolic PH (CTEPH), or other severe forms of PH, an urgent referral to a specialist PH centre is recommended [1]. The presence of rapidly worsening symptoms, recurrent syncope, signs of right ventricular failure, arrhythmias, hypotension, or tachycardia indicates haemodynamic instability, which also requires immediate attention [1]. Recognising these high-risk features early is critical to preventing rapid clinical deterioration.
Confirming the Diagnosis and Identifying the Subgroup
If the initial assessment raises suspicion of cardiac or pulmonary disease, further investigations may be undertaken. These may include pulmonary function tests, arterial blood gases, chest imaging (X-ray or computed tomography (CT)), cardiopulmonary exercise testing, and echocardiography to evaluate the heart structure and function [1]. When an alternative cause, such as left heart disease or lung disease, is identified, PH management is directed towards the underlying condition [1]. However, if no alternative cause can be identified and PH remains likely, especially in patients with intermediate or high probability or relevant risk factors, the patient should be referred to a specialist centre [1].
Following referral, patients typically undergo more invasive testing, such as right heart catheterisation. Right heart catheterisation remains the gold standard for confirming PH as it can provide definitive haemodynamic measurements, distinguish between pre-capillary and post-capillary disease, and help classify patients into specific PH subgroups [1].
Each PH subgroup presents with characteristic features [1].
PAH (Group 1) often affects younger individuals, who may present with mild hypoxaemia, right heart enlargement on imaging, and pre-capillary haemodynamics on catheterisation.
PH due to left heart disease (Group 2) usually affects older patients and shows left-sided cardiac enlargement, diastolic dysfunction, and post-capillary haemodynamics.
PH associated with lung disease (Group 3) commonly presents with hypoxaemia, pulmonary function abnormalities and reduced diffusing capacity.
CTEPH (Group 4) is characterised by perfusion defects on lung scintigraphy and evidence of chronic vascular obstruction on imaging.
Ongoing Monitoring and Risk Assessment
PH patients should undergo regular follow-ups, typically every three to six months at a specialist centre, to assess disease progression, evaluate treatment response, and detect early signs of deterioration [1]. These follow-up assessments typically include a clinical review, ECG, echocardiography or cardiac MRI, oxygen saturation or arterial blood gases, 6-minute walk testing, cardiopulmonary exercise testing, and repeat BNP/NT-proBNP measurements [1]. Additionally, repeat right heart catheterisation may be performed when clinically indicated [1].
Based on the assessment results, patients are stratified using validated risk assessment tools [1]. The three-strata model classifies patients as low, intermediate, or high risk, while the four-strata model further refines the intermediate risk categories [1]. The assessment of risk status can guide treatment decisions, including the initiation, escalation, or modification of therapy. Any evidence of clinical worsening or transition to a higher-risk category should prompt urgent reassessment.
In select patients with co-existing heart failure or recurrent hospitalisations, a pulmonary artery pressure (PAP) sensor may also be used to provide continuous remote monitoring. These small devices, which are typically implanted via a large vein into a branch of the pulmonary artery, measure and transmit real-time PAP data to clinicians, enabling early detection of adverse trends and more proactive treatment adjustments. The use of PAP sensors has been shown to reduce hospitalisations in patients with heart failure; although its effect on mortality is less certain [2–5].
In conclusion, PH is a progressive condition requiring early diagnosis, accurate subgroup classification, and regular monitoring to guide treatment. Risk-based follow-up, clinical assessments, and, in select cases, implantable pulmonary artery sensors help detect deterioration early and enable timely, personalised care, improving long-term outcomes. There remains a clear need for the development of additional non-invasive monitoring methods to further improve PH patient management.
