Slide 1: You are admitting a new patient for heart failure. What information can you procure from the baseline EKG?

Slide 2: This is a paced rhythm. What kind of pacemaker does the patient have?

EKG shows initial downward deflection in lead one, indicating initial forces moving forward. Tall R in V1. Pacer spikes. Clue to pacer spikes: this patient has an atrial spike and two ventricular spikes. Lateral leads are negative. This patient is A-V paced and has a RBBB-like QRS morphology.

This patient has a BiV PPM. Bi-ventricular permanent pacemaker.

Slide 3: In comparison to single lead PPM…

Single lead sits in RV apex. Conducts through right bundle then myocyte to myocyte on the left side. Produces tall broad R waves in lateral leads (one, V5-V6) with LBBB appearance.

A BiV PPM has multiple leads. Right atrium, right ventricle, coronary sinus/left ventricle epicardium. LV lead transverses SVC then RA then coronary sinus then sits in the venous system outside the LV. LV depolarization vector goes from left to right so lateral leads appear negative.

Slide 4: Chest films can help determine the PPM type. Use the CaRDIA-X algorithm to identify device types using chest films.

Chest film with arrows pointing to the RA, LV, and RV. Graphic with arrows pointing to the RA, LV, and RV.

Slide 5: PPM Indications.

Single lead. Conduction disease: in or above AV node with symptomatic bradycardia (ie. sick sinus, first degree AV block, Mobitz I) or below the AV node regardless of symptoms (ie. Mobitz II and third degree AV block)

BiV. BiV pacing or CRT is reserved for advanced heart failure. LVEF less than or equal to 35%, NYHA Class II or greater, wide QRS with LBBB (QRS greater than or equal to 150 ms). Cardiac resynchronization therapy improves quality of life, NYHA class, CHF admission, and mortality.

For CRT, the NNT for 1 life saved over 2.5 years is 10.

Check out the 12-Lead Thursday post from 1/24/2019 for a CRT case.


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