Check the trunk or stem for signs of rot - this will look like dark, weeping areas, may be soggy, with white spit or orange gunk oozing out, might even not smell very nice. If you have none, then just wait - the growing tips at the top have probably been destroyed, but your plant will eventually put out new growth lower down the trunk or from the base, or both, and you can then saw back to that point. If you find rotting, keep an eye on it - if its producing orange gunk, cut down beyond that point at the end of this month, if it can wait that long, and then wait again for new growth to show somewhere - this may take till end of June to show itself.