Extreme thrombocytosis and cardiovascular surgery: risks and management.

Extreme thrombocytosis is a major risk factor for excessive bleeding and for thrombosis, either of which can complicate cardiovascular surgical and interventional procedures. Extreme thrombocytosis can also cause an unusual syndrome, erythromelalgia, that results in a type of chronic microvascular occlusive arterial disease. We present the differential diagnosis of conditions that may lead to extreme thrombocytosis, 3 cases (each of which illustrates a different potential complication), and a review of the pertinent medical literature. Correcting excessive thrombocytosis is typically not difficult, whether electively or acutely, and effective therapy usually controls thrombosis and excessive hemorrhage post-procedurally.