Loss of right ventricular capture: When it is not the lead’s fault

Figures

• 

  Figure 1. A: Electrocardiogram (ECG) at presentation: an atrioventricular (AV) paced rhythm with premature atrial and ventricular complexes. QRS morphology is consistent with left ventricular (LV)-only pacing from the basal anterolateral LV. This is markedly different from (B), an ECG obtained after cardiac resynchronization therapy pacemaker implantation, which shows an AV paced rhythm with biventricular pacing.

• 

  Figure 2. Posteroanterior and lateral chest x-ray showing right-sided cardiac resynchronization therapy pacemaker with leads terminating in the right atrial appendage, right ventricular apex, and anterolateral branch of the coronary sinus.

• 

  Figure 3. Initial device interrogation showing rapid rise in the right ventricular (RV) lead threshold with stable lead impedances and sensing. Right atrial and left ventricular lead parameters remained stable from prior.

• 

  Figure 4. Computed tomography chest scan shows a necrotic 4-cm pericardial mass (orange arrow) adjacent to the right ventricular lead tip (blue arrow).

• 

  Figure 5. Algorithm for identifying cause of pacemaker failure to capture. CXR = chest x-ray.