Delay during deleting items from a SQLite Database in Windows Phone 8

  using (var db = new SQLite.SQLiteConnection(App.DB_Path))
  {
    var isItem = from i in Items.Where(x => x.IsChecked).ToList() select i;
    foreach (var item in isItem)
    {
       Items.Remove(item);
       item.IsChecked = false;
       var exists = db.Table<MyModel>().Where(c => c.Item ==      item.DisplayingItem).FirstOrDefault();
       if (exists != null)
         {
             db.RunInTransaction(() =>
             {
                 db.Delete(exists);
             });
         }
    }
}