How do I change the table's first row to a Heading row if it contains pgfs with tblHead tags

So far, I have the following in a JavaScript:

if (tbl.FirstRowInTbl.FirstCellInRow.FirstPgf.PgfFmt.Name === "tblHead")

        {

            if (tbl.FirstRowInTbl.RowType === 1)

                //1 is Constants.FV_ROW_BODY

                tbl.FirstRowInTbl.RowType = 0;

                // 0 is Constants.FV_ROW_HEADING

            else

                continue;

         }

        else

            continue;

This does not work. I'm not comfortable with tbl.FirstRowInTbl.FirstCellInRow.FirstPgf.PgfFmt.Name.

It is clearly wrong. How would I indicate I want to determine the tag of the first paragraph in the first row?

Any help is very much appreciated!

Thanks,

Ruth