Aspirin responsive platelet thrombophilia in essential thrombocythemia and polycythemia vera

Table 8 Vascular complications, hematocrit and platelet counts in 65 patients with classical polycythemia vera at time of presentation and during follow-up treatment: results from a retrospective observational study 1985

	At presentation	After treatment
No. of PV patients	65	65
Follow-up	-	225 patient-years
Hematocrit	0.60 (0.49-0.74)	< 0.48 before 1975
		< 0.45 since 1975
Platelet count (× 109/L) (mean)	512	390
Major vascular occlusive events	49%	35%
Microvascular/large vessels	13/19 (not specified)	Specified
Cerebrovascular events mainly TIA	-	15
Superficial thrombophlebitis
or venous thrombosis	-	20
Microvascular disturbances	-	5
Myocardial infarction	-	1
Mesenteric vein thrombosis	-	1

Study performed from 1962-1983. Phlebotomy to correct hematocrit and busulfan for platelet reduction and not treated with aspirin. Correction of hematocrit in PV to normal by bloodletting plus reduction of platelet count without the use of aspirin does not prevent vascular events. PV: Polycythemia vera; TIA: Transient ischemic attack. Originated from[87].