there's another post about pvc's and nsvt that has quite a few answers and info in it - you may want to read it;
NSVT or non sustained ventricular tachycardia can be benign or point to something else depending on where it originates inside the heart and if you have any structural problems. A cardiologist or EP would be able to figure that out with a full cardiac workup and give you an accurate answer.
Here's a thread for VT and PVC's from one of the doctor's here:
http://www.medhelp.org/posts/Heart-Disease/Idiopathic-Ventricular-Tachycardia-Ablation/show/1327314
"The runs of VT are non-sustained and very slow and very unlikely to cause any serious problems. Because your heart function is normal there really isn't any danger from having the VT runs."
"The only thing worth assessing is the number of PVC's in a 24 hour period. If it's greater than 15% of all the heart beats than there is a small risk of developing a PVC induced cardiomyopathy. We typically don't ablate PVC's unless they are symptomatic (such as in your case) or if they are very numerous (great than 15%)."
"The VT isn't ablated unless it's sustained or very symptomatic with episodes of passing out or nearly passing out. Sometimes it's difficult to induce the VT in the lab but becasue the PVCs typically look like the VT we sometimes go after them."
You should talk to a cardiologist and get it checked out if it does happen again.