A 3-year-old boy with tetralogy of Fallot and recurrent cyanotic spells was found to have severe thrombocytopenia with platelet counts in the range of 11–30,000/mm
3
. There was a hesitation to operate in view of the high bleeding risk due to profound thrombocytopenia. However, the total correction was done after excluding other causes of thrombocytopenia. His platelet count dramatically improved after the operation.