Fundamentals of CRT Therapy

Fundamentals of CRT Therapy The objective of CRT is to deliver ? - ✔✔100% BiV pacing It is critical to know that we are doing what during BiV therapy? - ✔✔capturing Right and left ventricular pacing typically gives yo ...

Fundamentals of CRT Therapy The objective of CRT is to deliver ? - ✔✔100% BiV pacing It is critical to know that we are doing what during BiV therapy? - ✔✔capturing Right and left ventricular pacing typically gives you opposite deflection in ? - ✔✔leads 1 and 3 In lead 1 the RV is ? - ✔✔positive In lead 1 the LV is? - ✔✔negative In lead 3 the RV is? - ✔✔negative In lead 3 the LV is? - ✔✔positive When assessing capture in a BiV device you should always look for what 4 distinct morphologies? - ✔✔presenting rhythm, underlying rhythm, rv capture, lv capture RV capture looks liked? - ✔✔LBBB LV capture looks like? - ✔✔RBBB What are unique challenges to LV capture? - ✔✔thresholds can be higher, CRT patients often suffer from ischemia, pacing sites ate limited venous anatomy, leads are not actively fixed more prone to move, heart shape and size may change (reverse remodel) What are the subjective minimally acceptable threshold values for the LV? - ✔✔<2.0V @0.5ms What is the threshold safety margin in the LV? - ✔✔1.5V x threshold in volts The first LV leads were? - ✔✔unipolar What is the advantage of unipolar LV leads? - ✔✔small in size What is the non traditional anode pacing configuration in a unipolar LV lead? - ✔✔extended bipolar- unipolar cathode to RV lead (anode ) What could unipolar/extended bipolar LV leads lead to? - ✔✔anodal stimulation Bipolar LV leads introduced? - ✔✔pacing vectors Bipolar LV leads allow for? - ✔✔electronic repositioning Medtronic bipolar leads can be programmed to? - ✔✔true bipolar or extended bipolar St Jude quadripolar pacing LV leads can not incorporate the? - ✔✔can The quadripolar LV lead is called? - ✔✔IS 4 Lead Why would a patient benefit from multipoint pacing? - ✔✔may reduce implant and post operative complications, may improve hemodynamics, may further narrow the qrs, may improve LV dP/dT, may reduce # of non responders What is multipoint pacing? - ✔✔pacing from 2 electrodes simultaneously What is a non responder? - ✔✔someone who doesn't benefit from CRT For implant testing in an IS 4 lead? - ✔✔use a connector tool to hook up to psa cables CRT devices require new leads which require? - ✔✔new headers CRT-P LV leads are labeled? - ✔✔LLLL What are the CRT-D device headers? - ✔✔DF4/IS4, DF4/IS1, DF1/IS1 How do the leads typically go in a CRT header? - ✔✔atrium on top, CS in middle, RV on bottom Extra cardiac pacing can stimulate the ? - ✔✔phrenic nerve The phrenic nerve contains? - ✔✔sensory, motor, and sympathetic nerve fibers The phrenic nerve provides? - ✔✔all of the motor innervation to the diaphragm Phrenic stimulation is tested for? - ✔✔at implant, 10 volt testing phrenic stimulation is often? - ✔✔positional phrenic stimulation may come or go with? - ✔✔reverse remodeling Phrenic nerve stimulation can be associated with? - ✔✔daily lead measurements (impedance testing) How do you troubleshoot extra cardiac stimulation? - ✔✔change pacing vector, electronically reposition the lead, use the vector that gives greatest distance from the phrenic nerve, maintain lv capture What should you consider when isolating the extra cardiac stimulation threshold? - ✔✔pulse width If there is extra cardiac stimulation program outputs into? - ✔✔the safety zone What is hyperpolarization of the myocardium at the anode? - ✔✔anodal stimulation Pacing at higher outputs creates enough? - ✔✔adjacent depolarization around the anode What are potential side effects of unipolar pacing? - ✔✔pocket stimulation derived from the anode In extended bipolar configuration the coil serves as? - ✔✔the pacing anode When using a dedicated bipolar RV lead in an extended bipolar configuration, the ring of the RV lead serves as the ? - ✔✔pacing anode You are more likely to get anodal stimulation with? - ✔✔dedicated bipolar RV leads in an extend bipolar LV config and higher outputer Anodal capture of RV in a BiV can make you think ? - ✔✔you lost capture but you didn't