Pulmonary HTN and Cor pulmonale

Question 1

What is the definition of pulmonary hypertension (PH)?

Answer 1

Mean pulmonary arterial pressure (mPAP) at or greater than 20 mmHg at rest.

Question 2

What are the clinical signs associated with pulmonary hypertension?

Answer 2

Progressive exertional dyspnea, presyncope, syncope, or exertional angina.

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Signs of right heart failure such as peripheral edema, elevated JVP, IVC Engorgement , loud P2, right sided S3, right ventricular heave, holosystolic tricuspid regurg murmur.

Question 3

What are the primary complications of right-sided heart congestion in the setting of pulmonary hypertension?

Answer 3

Venous congestion and IVC Engorgement: Patients experience symptoms of high right atrial pressure, such as peripheral edema, abdominal distension, early satiety, ascites, congestive hepatopathy, and oliguria (cardiorenal).

Question 4

When patients with pulmonary hypertension start to experience presyncope or syncope, what does this say about their heart condition?

Answer 4

In pulmonary hypertension, presyncope with the Valsalva maneuver (coughing/defecation) likely reflects poor RV output (rather than a ventricular arrhythmia). This is due to limited cardiac output. Cardiac output cannot be sufficiently augmented during exercise, leading to exertional fatigue and syncope/presyncope. Marginal RV function renders patients susceptible to vagal bradycardia and hypotension (eg, defecation and cough syncope, stooping to tie shoes).

Question 5

What would be seen on CXR in a patient with pulmonary HTN?

Answer 5

Bilateral hilar enlargement. The high pulmonary artery pressure leads to dyspnea and chest tightness and are manifestations of vessel wall stretch. Rarely, hemoptysis may occur.

Question 6

What does an ECG do to help render a diagnosis of pulmonary hypertension?

Answer 6

ECG will show a right axis deviation. Additionally, patients with pulmonary hypertension can experience increased RV demand ischemia, whereas the LV is solely perfused in diastole, the RV is perfused during systole. Therefore the right side of the heart is more susceptible to low stroke volume. Patients may experience exertional chest pain related to episodes of RV ischemia, further contributing to RV decline.

Question 7

Is biopsy ever indicated with pulmonary hypertension?

Answer 7

Diagnosis of pulmonary hypertension is based on clinical presentation, noninvasive tests, and hemodynamic data (eg, echocardiography). Tissue sampling typically adds no further information and carries a high risk for complications from biopsy (eg, high-pressure bleeding), so essentially, NO!

Question 8

How is pulmonary hypertension diagnosed?

Answer 8

A transthoracic echocardiogram is used as a non-invasive evaluation of pressures initially. There will be evidence of right ventricular enlargement as well as right atrial enlargement. An ECHO is followed by a right heart catheterization, as a right heart cath is the most accurate diagnostic test.

Question 9

What is the gold standard for diagnosing pulmonary hypertension?

Answer 9

Right heart catheterization.

Question 10

What are the five WHO classifications of pulmonary hypertension?

Answer 10

1. Pulmonary arterial hypertension (PAH)
2. Left heart disease (mitral stenosis)
3. Lung disease/chronic hypoxemia
4. Chronic thromboembolic pulmonary hypertension (CTEPH)
5. Multifactorial or unclear mechanisms.

Question 11

What is the most common cause of pulmonary hypertension?

Answer 11

WHO class III; Lung diseases such as COPD, interstitial lung disease, and obstructive sleep apnea.

Question 12

If the cause for pulmonary hypertension is idiopathic, what class of pulmonary hypertension does this belong to?

Answer 12

This is class I pulmonary hypertension.

Question 13

Drugs/toxins (e.g., amphetamines), toxins, HIV, schistosomiasis, belong to which class of pulmonary hypertension?

Answer 13

Class I

Question 14

If pulmonary arterial hypertension (PAH) appears to have a familial component, which gene is implicated and what class of pulmonary hypertension does this belong to?

Answer 14

BMPR-2 mutation, Class I pulmonary hypertension.

Question 15

Connective tissue diseases (e.g., scleroderma, CREST) are associated to which class of pulmonary hypertension?

Answer 15

Class I

Question 16

Between CREST and idiopathic pulmonary hypertension, which confer the worse prognosis?

Answer 16

CREST (a subset of systemic sclerosis) leads to progressive vasculopathy of the pulmonary arteries, leading to increased pulmonary vascular resistance and right heart strain. PAH in systemic sclerosis is particularly concerning because it has a worse prognosis compared to idiopathic PAH and often presents insidiously with exertional dyspnea and right heart failure symptoms.

Question 17

What are the initial elements for working up Group 1 PAH?

Answer 17

• check family history
• screen and treat underlying autoimmune disease (connective tissue disease)
• evaluate for drugs or toxins (check urine for amphetamines)
• test for infections (schistosomiasis) if indicated
• management of HIV

Question 18

Treatment of all forms of pulmonary hypertension involves … ?

Answer 18

• Prescribe appropriate vasodilator:
• Endothelin receptor antagonists (bosentan, ambrisentan, macitentan) to prevent the growth of pulmonary vasculature.
• PDE-5 inhibitors (sildenafil, tadalafil).
• prostacyclin agonists (selexipag is used first, followed by epoprostenol, then treprostinil).
• CCBs (diltiazem), however, these have weak efficacy.
• IV prostacyclin agonist (epoprostenol or treprostinil) for severe cases.

Question 19

What causes Group 2 pulmonary hypertension?

Answer 19

Elevated left ventricular end-diastolic pressure (LVEDP) or pulmonary capillary wedge pressure (PCWP), often due to left-sided heart failure or significant valvular disease.

Question 20

How is Group 2 PH managed?

Answer 20

Perform an ECHO and optimize left ventricular function (e.g., heart failure therapy) and treat significant valve disease such as mitral stenosis. A normal left ventricular function on echocardiography and normal pulmonary capillary wedge pressure (<18 mm Hg) rule out PH due to left-sided heart failure. If this is the underlying cause for pulmonary hypertension, treatment would involve addressing either valvular disease, heart failure, or reduced ejection fraction with valve replacement, or heart failure medications such as a renin-angiotensin inhibitors or cardioselective beta blocker.

Question 21

What causes Group 3 pulmonary hypertension?

Answer 21

Chronic lung diseases (e.g., COPD, interstitial lung disease) or chronic hypoxemia (e.g., obstructive sleep apnea).

Question 22

What would be the workup for Group 3 PAH?

Answer 22

Pulmonary function testing, chest imaging, or polysomnography, would serve to either rule in or out PH due to lung disease or sleep-disordered breathing (eg, sleep apnea).

Question 23

How is Group 3 PH managed?

Answer 23

Treat the underlying respiratory condition (e.g., bronchodilators for COPD, CPAP for OSA). PH due to lung disease and/or chronic hypoxemia (group 3) is treated by addressing the underlying lung conduction (eg, inhaled muscarinic antagonist for chronic obstructive pulmonary disease)

Question 24

Pulmonary HTN secondary to Interstitial Lung Disease (ILD) is treated with … ?

Answer 24

Antifibrotic therapy such as pirfenidone or nintedanib.

Question 25

What causes Group 4 pulmonary hypertension (CTEPH)?

Answer 25

Chronic thromboembolic disease, typically after multiple pulmonary embolisms (PEs).

Question 26

How is Group 4 CTEPH managed?

Answer 26

Evaluation would require a V/Q scan or a pulmonary angiography. This is treated with Pulmonary thromboendarterectomy surgery (curative) and lifelong anticoagulation.

Question 27

Which medication is given to treat chronic thromboembolic disease and increases vasodilatory nitrous oxide?

Answer 27

Riociguat. This increases nitric oxide by stimulating guanylate cyclase and increasing vasodilation by generating cGMP.

Question 28

What are the general measures for managing all forms of pulmonary hypertension?

Answer 28

Maintain normoxia, euvolemia, and sinus rhythm; contraceptive counseling; immunizations; cardiac rehabilitation. vvvvvvvvvvvv For all forms of pulmonary hypertension, general supportive measures aim to maintain physiologic homeostasis (ie, normoxia, euvolemia, sinus rhythm). Furthermore, the following components of care include, **avoiding pregnancy** due to maternal and fetal mortality remaining unacceptably high (25%-50%), even with optimal pharmacotherapy. Right ventricular (RV) failure and obstructive physiology are especially dangerous for normal peripartum volume shifts and anesthesia. Most pulmonary vasoactive medications are pregnancy class X teratogens (absolutely contraindicated). Guidelines issue a strong recommendation to avoid pregnancy, advising non-estrogen-based contraception (lower risk for venous thrombosis for women of childbearing age. **Regular aerobic exercise** in a supervised cardiac/pulmonary rehabilitation program, aerobic exercise, as tolerated, is safe and effective for restoring functional status. Strenuous weightlifting and other Valsalva maneuvers inhibiting venous return should be avoided. Provide **nutritional support** with a dietary plan to regulate salt and fluid intake and achieve weight loss or gain (eg, pulmonary cachexia), targeting a healthy BMI. Patients should be referred to an accredited PH program due to the superior outcomes. Such centers can offer psychosocial counseling and assistance to cope with the many dimensions of PH, including family planning.

Question 29

Why should women with pulmonary hypertension avoid pregnancy?

Answer 29

Pregnancy significantly increases maternal mortality (25-50%) due to peripartum volume shifts and right ventricular failure.

Question 30

What hematologic disorder can lead to pulmonary hypertension?

Answer 30

Polycythemia vera. This is Class 5 PAH (multifactorial).

Question 31

What is the definitive treatment for refractory pulmonary hypertension?

Answer 31

Bilateral lung transplantation.

Question 32

What dangerous cardiac condition is secondary to chronic pulmonary hypertension?

Answer 32

Right sided heart failure, cor pulmonale.

Question 33

What is cor pulmonale?

Answer 33

Isolated right heart failure caused by advanced pulmonary hypertension due to mechanisms other than left heart failure.

Question 34

What are the clinical features of cor pulmonale?

Answer 34

Exertional dyspnea, angina, syncope, signs of right heart failure (JVD, peripheral edema), RV heave, hepatomegaly, ascites, abdominal distention, and early satiety.

Question 35

How is cor pulmonale diagnosed?

Answer 35

Right heart catheterization, which shows elevated pulmonary pressures.

Question 36

What are common noninvasive tests for pulmonary hypertension?

Answer 36

Echocardiography, pulmonary function tests, V/Q scan, and chest imaging.

Question 37

How is cor pulmonale managed?

Answer 37

Diuretics and treatment of underlying pulmonary hypertension.

Question 38

What dangerous cardiac rhythm occurs with right sided heart failure or pulmonary hypertension?

Answer 38

Cardiac arrest in the setting of PH and RV obstruction is due to **pulseless electrical activity** rather than a shockable rhythm.