Chapter 32: Pulmonary Arterial Hypertension

Question 1

Pulmonary arterial hypertension (PAH) can be caused by all of the following, EXCEPT?

A. HIV
B. Genetic inheritance
C. Connective tissue disease
D. T2DM
E. Advanced liver disease

Answer 1

D

PAH is not caused by T2DM

Question 2

Which of the following statements regarding PAH is correct? (Select all that apply)

A. Characterized by an increase in prostacyclin and a decrease in thromboxane A2
B. Characterized by a decrease in prostacyclin and a increase in thromboxane A2
C. Characterized by an increase in endothelin and an increase in prostacyclin
D. Characterized by a decrease in prostacyclin and a decrease in thromboxane A2
E. Characterized by an increase in endothelin and a decrease in prostacyclin

Answer 2

B and E are correct.

PAH stems from an imbalance of vasoconstrictor substances and an imbalance of proliferation and apoptosis in the pulmonary arteries. Vasoconstrictors, endothelin and thromboxane A2, are increased in PAH whereas vasodilators like prostacyclin are decreased.

Question 3

What is the most common cause of death in patients with PAH?

Answer 3

HF

This stems from the pathophysiology of the disease: Increased amounts of vasoconstrictors results in reduced blood flow and high BP in the pulmonary vasculature. Pulmonary artery walls thicken as the amount of muscle increases and scar tissue forms on the artery walls (vasoproliferation). Narrower arteries make it more difficult for the right ventricle to pump blood into the lungs. This increases the workload of the right ventricle leading to enlargement and right-sided HF.

Question 4

What is the target INR in patients with PAH taking warfarin?

Answer 4

INR: 1.5 - 2.5

The vasoconstrictor/vasodilator imbalance and other altered pathways makes patients with PAH more likely to form clots (prothrombotic), and anticoagulation is recommended

Question 5

Which of the following drugs CAN cause PAH? (Select all that apply)

A. Cocaine
B. Escitalopram
C. Adipex® 
D. Elavil®
e. Dasatinib

Answer 5

A, B, C, and E are correct

Drugs that cause PAH include cocaine, SSRIs (like escitalopram (Lexapro®), weight loss agents (like phentermine (Adipex®) and lorcaserin (Belviq®), dasatinib (Sprycel®) which is an antineoplastic agent tyrosine kinase inhibitor, diazoxide (Proglycem®) for hypoglycemia condition, and methamphetamine.

D is incorrect

amitriptyline (Elavil®) is a TCA indicated for depression, but used off-label for a variety of indications such as chronic pain management, diabetic neuropathy, migraine prevention, PTSD, and interstitial cystitis

Question 6

Initial therapy for PAH includes warfarin for anticoagulation, loop diuretics for volume overload, oxygen therapy for hypoxemia, and maybe digoxin if low cardiac output or patient in afib. Patients will then undergo an acute vasoreactivity testing to see if they respond to this class of medications to better manage their PAH?

Answer 6

Calcium-channel blockers

The most common CCBs used are long-acting nifedipine, diltiazem, and amlodipine (Verapamil is NOT used due to more negative inotropic effects compared to cardizem)

Question 7

Since PAH is characterized by a decrease in vasodilators like prostacyclin, it makes sense that pharmacotherapy includes prostacyclin analogues, also called Prostanoids). Which of the following generic prostacyclin analogues are matched correctly with their brand names? (Select all that apply)

A. Epoprostenol - Flolan®
B. Bosentan - Tracleer®
C. Iloprost - Ventavis®
D. Treprostinil - Adcirca®
E. Treprostinil - Tyvaso®

Answer 7

A, C, and E are correct

Epoprostenol - Flolan® and Veletri®

Treprostenol - Remodulin® (SC/IV), Tyvaso® (inhaled), Orenitram® (oral)

Iloprost (Ventavis®)

B and D are incorrect
Bosentan is correctly matched to its brand name Tracleer®, but is an endothelin receptor antagonist, not a prostacyclin analogue.

Adcirca® is the brand name for tadalafil, a PDE-5 inhibitor