Modular cardiac rhythm management using q to lv activation measures

A method of implanting a leadless cardiac pacemaker (LCP), the method of implant using an LCP delivery system comprising a handle assembly, an shaft extending distally from the handle assembly and including a distal region, and an LCP containment housing coupled to the distal region of the shaft and extending distally therefrom, the LCP containment housing adapted for holding the LCP during implantation thereof to a patient's heart, wherein the distal region and/or LCP containment housing comprise a plurality of electrodes adapted to sense cardiac signals during implantation of the LCP;

• the method comprising:
• inserting the LCP containment housing into a blood vessel of the patient and advancing the LCP containment housing and at least a portion of the shaft into the blood vessel to bring the LCP containment housing proximity with a portion of the myocardium;
• using the electrodes of the LCP delivery system to capture one or more cardiac cycles while the containment housing is adjacent to the portion of the myocardium to sense a ventricular activation time for the myocardium adjacent the containment housing;
• capturing a surface electrocardiogram for the patient and identifying a Q-wave for at least one of the one or more cardiac cycles;
• determining a Q-wave to ventricular activation interval and comparing it to an interval threshold and, if the threshold is not exceeded determining that the portion of the myocardium is not a suitable location for implanting the LCP, and manipulating the handle to adjust the position of the containment housing relative to the myocardium to identify a location on the myocardium of later ventricular activation relative to a Q-wave identified on the surface electrocardiogram;
• and
• implanting the LCP at a location of the myocardium at which the interval threshold is exceeded.