A method and implantable medical device system for delivering a left ventricular (LV) cardiac pacing therapy via a single-pass coronary sinus lead and sensing far-field cardiac signals via one or more far-field sensing vectors formed between the plurality of electrodes. Beat morphologies corresponding to the far-field cardiac signals are determined, and a beat morphology match between each of the far-field beat morphologies and an intrinsic beat morphology template is determined so that one of loss of LV capture, pseudo fusion and loss of synchrony is determined in response to the determined beat morphology match. One of a loss of capture adjustment, a pseudo fusion adjustment, and a resynchronization adjustment is performed in response to the determined one of loss of LV capture, pseudo fusion and loss of synchrony in response to the determined beat morphology match to generate an adjusted LV cardiac pacing therapy.
