Saturday, October 3, 2015

Allergic Angina

Allergic angina
Also known as "Kounis syndrome"
Named after the greek cardiologist "Nicholas Kounis" who has first described it in 1991.
- It is an acute coronary syndrome (may be STEMI) that is precipitated by an allergic reaction (e.g., bee sting)
Pathophysiology:
- Allergic insults resulting in mast cell degranulation and release of inflammatory mediators e.g, histamine, neutral proteases, arachidonic acid derivatives, platelet activating factors and a variety of cytokines and chemokines. These substances cause coronary vaso spasm and plaque rupture.
- Tryptase release leading to plaque rupture through activation of interstitial collagenase, gelatinase and stromelysin.
Diagnosis: clinical condition with confirmation by increased serum tryptase level.
Treatment consideration: The usual anti-anginal medication with the following treatment changes:
- Antianaphylactic measures: epinephrine, corticosteroids and antihistaminics.
- Pain control by Fentanyl not morphine as morphine is associated with histamine release.
- Avoid beta blockers. Even reverse beta blockers if given with glucagon. Do not give epinephrine if beta blockers are give except after reversal due to fear of unopposed alfa action.