A medical device system for determining pacing threshold data that includes a cardiac capture sensor, a phrenic nerve stimulation sensor, a pulse generator selectively coupled to a plurality of electrode vectors to deliver a phrenic nerve stimulation pulse, and a processor coupled to the cardiac capture sensor, the phrenic nerve stimulation sensor and the pulse generator and configured to deliver the phrenic nerve stimulation pulse along the plurality of electrode vectors, determine, for each vector of the plurality of vectors, whether phrenic nerve stimulation is detected in response to the delivered phrenic nerve stimulation, deliver a pacing pulse along only the vectors of the plurality of vectors that phrenic nerve stimulation is determined not to be detected, and determine pacing capture thresholds in response to the delivered pacing pulse.
