Review Question - QID 212430

This patient's history of digital color changes from white to blue to red in response to cold is consistent with primary Raynaud phenomenon, which is best managed with dihydropyridine calcium channel blockers (DHP-CCBs) such as amlodipine.

Primary Raynaud phenomenon (RP) refers to vasospasm of the arteries in response to cold temperatures or emotion that leads to a transient decrease in blood flow. This most commonly occurs in the digits, causing them to change color from white to blue to red before returning to normal. Secondary RP refers to vasospasm in the setting of an associated diagnosis, often an autoimmune condition such as scleroderma or CREST. In severe cases of secondary RP, digital ischemia can result in ulcerations, necrosis, and even require amputation. Patients should initially be advised to avoid triggers and to quit smoking. In the absence of improvement, the first-line medical treatment are DHP-CCBs such as amlodipine, which promote arterial smooth muscle relaxation via prevention of calcium influx.

Incorrect Answers:
Answer 2: Phenylephrine is a direct alpha agonist, which will promote peripheral vasoconstriction and potentially worsen active primary Raynaud phenomenon.

Answer 3: Propranolol is a beta-blocker with activity on beta-1 and beta-2 receptors. Loss of beta-2-mediated vasodilation may promote Raynaud phenomenon. Beta-blockers as a class have been associated with Raynaud phenomenon.

Answer 4: Sildenafil is a phosphodiesterase-5 inhibitor that prevents degradation of cyclic-GMP, promoting vasodilation. Sildenafil is indicated in patients with Raynaud phenomenon that are refractory to DHP-CCB therapy.

Answer 5: Thoracic sympathectomy removes sympathetic tone to the digital arteries, inhibiting vasoconstriction. This procedure is indicated only in patients with severe disease that have failed medical management.

Bullet Summary:
Dihydropyridine calcium channel blockers are the first-line medical therapy for Raynaud phenomenon.