Hemodynamic Surveillance of Ventricular Pacing Effectiveness with the Transvalvular Impedance Sensor

Figure 2

Real-time telemetry of event markers (1st tracing) and transvalvalvular impedance (2nd tracing) with simultaneous surface ECG recording (I, III, and aVR from the 3rd to bottom tracings, all with the same voltage scale) during ventricular threshold analysis in VVI. On the markers tracing, long bars represent ventricular pacing and short bars atrial sensing. The 6th spike energy was below the threshold. The capture failure was recognized by the TVI system and the pacemaker promptly increased the pulse amplitude, restoring effective ventricular stimulation.