Take-home teaching point: carcinoid heart disease is caused by fibrous deposits on the valves, and affects the RIGHT side of the heart (tricuspid regurgitation most commonly but can also cause pulmonic valve stenosis or regurgitation).
- Pathophysiology: not entirely clear, but to develop carcinoid heart, must have serotonin (and other humors) to go directly into the systemic circulation (e.g. liver mets, primary ovarian carcinoid that drains directly into IVC). The classic GI primary carcinoid tumor will not cause this since the portal circulation drains into the liver where the serotonin can get processed.
- See the section on pathophys in this paper (PMID 23955119, from Harry) and in this paper (PMID 18071089, from Josh Shak)
- Often doesn’t affect the LV since the pulmonary vasculature is also thought to process/inactivate these substances. Left-sided involvement occurs in less than 10% of carcinoid heart.
- Get left-sided disease when there is a R->L shunt (either intracardiac or pulmonary) or primary bronchial carcinoid
- What about that octreotide stuff? It’s a somatostatin analog that inhibits tumor release of bioactive substances like serotonin. Works to treat the symptoms of carcinoid syndrome (flushing, diarrhea) but unclear if treatment does anything to treat carcinoid heart disease. Not commonly used for this.
- Don’t use epinephrine or norepinephrine if possible in these patients. Can cause bradykinin release and paradoxically worsen vasodilation and hypotension! (http://m.ceaccp.oxfordjournals.org/content/11/1/9.full)
- If you want to learn more about tricuspid regurgitation, check out this paper written by Elyse Foster. Helpful DDx for thiking about tricuspid regurgitation (PMID 15473480)