Read hierarchical excel pivot table from C#

I want to read excel pivot table data and store it in a sql table. Pivot table is having ten RowFields and six DataFields. I have written the code to run through all the combination of PivotItems and calling the GetPivotData() to check whether any valid data available in the pivot table. Still it is taking ten minutes to finish the execution even after get rid of checking bottom level data if top level summary data is not available. Really appreciate Any Idea to read and get the unpivot data quickly from excel hierarchical pivot table?