A 28-year-old woman reports gradually worsening shortness of breath over the past 10–12 months. She now needs to pause after walking short distances. Examination reveals a forceful right-ventricular heave, elevated JVP with a prominent ‘a’ wave, and a loud pulmonary component of S2 at the left upper sternal border. Lung fields are clear on chest X-ray. Which underlying condition best explains her presentation?

A. Calcific aortic valve narrowing
B. Long-standing systemic hypertension
C. Hypertrophic obstructive cardiomyopathy
D. Ventricular conduction delay
E. Elevated pulmonary arterial pressures

Table of Contents

Correct Answer: E. Elevated pulmonary arterial pressures (Pulmonary Hypertension)

DETAILED EXPLANATION

Why this is pulmonary hypertension (PH)

This patient has the classic triad of pulmonary hypertension:

Loud P2 → from forceful pulmonic valve closure due to high pulmonary artery pressure.
Right ventricular heave → RV hypertrophy from chronic pressure overload.
Progressive exertional dyspnoea → hallmark of PH; lungs remain clear as pathology is vascular, not parenchymal.

Normal chest X-ray lung fields argue against heart failure, aortic stenosis, or hypertrophic cardiomyopathy.

DEFINITION & CLASSIFICATION OF PULMONARY HYPERTENSION (PH)

Definition (2022 ESC/ERS updated):

Mean Pulmonary Artery Pressure (mPAP) > 20 mmHg at rest (via right-heart catheter).
And for pulmonary arterial hypertension (PAH):
- Pulmonary vascular resistance (PVR) > 2 Wood units
- Pulmonary artery wedge pressure ≤ 15 mmHg

WHO CLASSIFICATION OF PH (5 Groups)

Group	Cause	Examples
1 – PAH	Disease of pulmonary arteries	Idiopathic, heritable (BMPR2), connective tissue disease (SSc), HIV, portal HTN, drugs (methamphetamines), congenital heart disease
2 – PH due to left heart disease	High left-sided filling pressures	LV dysfunction, valvular disease
3 – PH due to lung disease/hypoxia	Chronic parenchymal disease	COPD, ILD, OSA
4 – Chronic thromboembolic PH (CTEPH)	Obstructive thrombi	Post-PE
5 – Miscellaneous	Multifactorial	Sarcoid, myeloproliferative disorders

TREATMENT OF PULMONARY HYPERTENSION (OVERVIEW)

1. PAH-specific therapy (Group 1 only)

Based on pathways:

Endothelin pathway:

Endothelin receptor antagonists (ERAs):
- Bosentan, Ambrisentan, Macitentan
  Effect: ↓ PVR → ↓ RV afterload → ↑ exercise capacity.

Nitric Oxide pathway:

PDE-5 inhibitors: Sildenafil, Tadalafil
sGC stimulators: Riociguat
Effect: Vasodilation of pulmonary arteries.

Prostacyclin pathway:

Epoprostenol (IV), Treprostinil (IV/SC/inhaled/oral), Iloprost (inhaled), Selexipag (oral)
Effect: Potent vasodilation + anti-proliferative effects.

General approach (ESC algorithm):

Perform Vasoreactivity testing during RHC.
- If positive: use high-dose calcium channel blockers (rare subset).
Otherwise start initial combination therapy (e.g., ERA + PDE-5 inhibitor).
Escalate to triple therapy including prostacyclin for advanced disease.

2. PH due to left heart disease (Group 2)

Treat underlying: ACEi/ARB/ARNI, beta-blockers, diuretics, valvular surgery.
PAH drugs NOT indicated.

3. PH due to lung disease (Group 3)

Treat primary lung disease: oxygen therapy, CPAP for OSA, stop smoking.

4. CTEPH (Group 4)

Pulmonary endarterectomy = CURATIVE.
If inoperable → Riociguat or Balloon Pulmonary Angioplasty.

5. Miscellaneous (Group 5)

Treat underlying cause.

WHY OTHER OPTIONS ARE WRONG

Aortic stenosis

Soft/absent A2, systolic murmur at right upper sternal border.

Hypertensive heart disease

LV changes, crackles if HF develops.

Hypertrophic cardiomyopathy

Harsh systolic murmur ↑ with Valsalva; lungs often normal but P2 not accentuated.

LBBB

Paradoxical splitting but not loud P2.

CHEAT SHEET (EXAM-CRITICAL POINTS)

mPAP >20 mmHg defines PH.
Loud P2 = pulmonary hypertension until proven otherwise.
Clear lungs + RV heave + loud P2 = PAH.
WHO Group 1 = treat with PAH-specific drugs.
Vasoreactivity testing identifies rare CCB responders.
ERA + PDE5i is standard first-line combination therapy.
Prostacyclins for severe or high-risk PAH.
Group 2 PH → treat LV disease; PAH drugs contraindicated.
Group 3 PH → treat hypoxia/lung disease.
Group 4 PH → endarterectomy is curative.
Syncope on exertion = advanced PAH (bad prognosis).

FLASHCARDS (20 CARDS)

1. What defines PH?
mPAP >20 mmHg at rest.

2. What extra criteria define PAH?
PVR >2 WU, PAWP ≤15 mmHg.

3. Which heart sound is loud in PH?
P2.

4. Main symptom of PH?
Exertional dyspnoea.

5. Cause of RV heave?
RV hypertrophy from pressure overload.

6. Most common type of PH?
Group 2 (left heart disease).

7. Most important risk factor for idiopathic PAH?
BMPR2 mutation.

8. Which test confirms PH?
Right-heart catheterisation.

9. What is vasoreactivity testing?
Short-acting vasodilator to identify CCB responders.

10. Drug class: Bosentan?
Endothelin receptor antagonist.

11. Drug class: Sildenafil?
PDE-5 inhibitor.

12. Drug class: Riociguat?
sGC stimulator.

13. Drug class: Epoprostenol?
Prostacyclin analogue.

14. Treatment for CTEPH?
Pulmonary endarterectomy.

15. Which PH group uses PAH drugs?
Group 1 only.

16. Clear lungs + loud P2 suggests?
PAH.

17. Physical sign of severe PH?
Right ventricular heave.

18. Sign of advanced disease?
Exertional syncope.

19. Group 3 PH main therapy?
Oxygen + treat lung disease.

20. Best initial therapy for PAH?
ERA + PDE-5 inhibitor combination.

MCQs FOR REVISION

1. Clear lungs, loud P2, progressive dyspnea – first test?

A. CT chest
B. Echocardiography
C. Coronary angiography
D. Pulmonary function test
Answer: B (screening tool; RHC is confirmatory)

2. Which drug improves PAH by blocking endothelin-1?

A. Tadalafil
B. Macitentan
C. Epoprostenol
D. Riociguat
Answer: B

3. In CTEPH, which therapy is curative?

A. Sildenafil
B. Pulmonary endarterectomy
C. Epoprostenol
D. Selexipag
Answer: B

4. Which group of PH uses PAH-targeted drugs?

A. Group 2
B. Group 3
C. Group 1
D. Group 5
Answer: C

5. Exertional syncope suggests which pathophysiology?

A. Mitral regurgitation
B. Severe pulmonary hypertension
C. Atrial fibrillation
D. RV volume overload
Answer: B

SUMMARY

Pulmonary hypertension is defined as a mean pulmonary artery pressure above 20 mmHg and presents classically with progressive exertional dyspnoea, a loud P2, elevated JVP, and right-ventricular heave. The lungs are typically clear because the problem is vascular rather than parenchymal. Pulmonary arterial hypertension (PAH), a subset of PH, additionally requires a PVR >2 WU and wedge pressure ≤15 mmHg. PH is categorised into five groups: PAH, left-heart disease, lung disease/hypoxia, chronic thromboembolic PH, and miscellaneous causes. Right-heart catheterisation is essential for diagnosis and haemodynamic classification. Vasoreactivity testing identifies the small minority who benefit from high-dose calcium channel blockers. Most patients require pathway-targeted therapy, usually starting with dual therapy using an endothelin receptor antagonist and a PDE-5 inhibitor. Prostacyclin analogues are added in advanced disease. Group 2 PH is managed by treating LV dysfunction and valvular problems, while Group 3 requires optimisation of lung disease and correction of hypoxia. Chronic thromboembolic PH is potentially curable with pulmonary endarterectomy, and riociguat is used when surgery is not possible. A loud P2 is the single most important physical sign of pulmonary hypertension. Exertional syncope marks severe disease and poor prognosis. Recognition of PH patterns in exam questions relies on clear lungs, RV heave, loud P2, and exertional limitations.

Dyspnea