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Hemodynamic Surveillance of Ventricular Pacing Effectiveness with the Transvalvular Impedance Sensor.

Calvi V, Pizzimenti G, Lisi M, Doria G, Vasquez L, Lisi F, Felis S, Tempio D, Virgilio A, Barbetta A, Di Gregorio F - Adv Med (2014)

Bottom Line: When the energy scan resulted in capture loss, the TVI system must detect the failure and increase the output voltage.The procedure was never interrupted by the physician, as the automatic energy regulation ensured full patient's safety.The median prevalence of false alarms was 0.336%.

View Article: PubMed Central - PubMed

Affiliation: Arrhythmology OU, Ferrarotto Hospital, University of Catania, Catania, Italy.

ABSTRACT
The Transvalvular Impedance (TVI) is derived between atrial and ventricular pacing electrodes. A sharp TVI increase in systole is an ejection marker, allowing the hemodynamic surveillance of ventricular stimulation effectiveness in pacemaker patients. At routine follow-up checks, the ventricular threshold test was managed by the stimulator with the supervision of a physician, who monitored the surface ECG. When the energy scan resulted in capture loss, the TVI system must detect the failure and increase the output voltage. A TVI signal suitable to this purpose was present in 85% of the tested patients. A total of 230 capture failures, induced in 115 patients in both supine and sitting upright positions, were all promptly recognized by real-time TVI analysis (100% sensitivity). The procedure was never interrupted by the physician, as the automatic energy regulation ensured full patient's safety. The pulse energy was then set at 4 times the threshold to test the alarm specificity during daily activity (sitting, standing up, and walking). The median prevalence of false alarms was 0.336%. The study shows that TVI-based ejection assessment is a valuable approach to the verification of pacing reliability and the autoregulation of ventricular stimulation energy.

No MeSH data available.


Related in: MedlinePlus

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.
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fig2: 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.

Mentions: An example of the system operation is illustrated in Figure 2, which shows a ventricular threshold analysis with overdrive VVI stimulation. When ventricular pacing was effective, a TVI signal featuring the expected increase in the QT interval was generated at every beat. In contrast, when the stimulus did not reach the threshold (6th pulse in Figure 2) the electromechanical response was absent, no ejection occurred, and therefore TVI remained at the diastolic level. The absence of a TVI increase after the ventricular spike was detected by the pacemaker, which restored the programmed pulse energy and closed the procedure, switching back to VDD from the temporary VVI pacing mode. During the reprogramming process, TVI telemetry was suspended.


Hemodynamic Surveillance of Ventricular Pacing Effectiveness with the Transvalvular Impedance Sensor.

Calvi V, Pizzimenti G, Lisi M, Doria G, Vasquez L, Lisi F, Felis S, Tempio D, Virgilio A, Barbetta A, Di Gregorio F - Adv Med (2014)

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.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4590946&req=5

fig2: 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.
Mentions: An example of the system operation is illustrated in Figure 2, which shows a ventricular threshold analysis with overdrive VVI stimulation. When ventricular pacing was effective, a TVI signal featuring the expected increase in the QT interval was generated at every beat. In contrast, when the stimulus did not reach the threshold (6th pulse in Figure 2) the electromechanical response was absent, no ejection occurred, and therefore TVI remained at the diastolic level. The absence of a TVI increase after the ventricular spike was detected by the pacemaker, which restored the programmed pulse energy and closed the procedure, switching back to VDD from the temporary VVI pacing mode. During the reprogramming process, TVI telemetry was suspended.

Bottom Line: When the energy scan resulted in capture loss, the TVI system must detect the failure and increase the output voltage.The procedure was never interrupted by the physician, as the automatic energy regulation ensured full patient's safety.The median prevalence of false alarms was 0.336%.

View Article: PubMed Central - PubMed

Affiliation: Arrhythmology OU, Ferrarotto Hospital, University of Catania, Catania, Italy.

ABSTRACT
The Transvalvular Impedance (TVI) is derived between atrial and ventricular pacing electrodes. A sharp TVI increase in systole is an ejection marker, allowing the hemodynamic surveillance of ventricular stimulation effectiveness in pacemaker patients. At routine follow-up checks, the ventricular threshold test was managed by the stimulator with the supervision of a physician, who monitored the surface ECG. When the energy scan resulted in capture loss, the TVI system must detect the failure and increase the output voltage. A TVI signal suitable to this purpose was present in 85% of the tested patients. A total of 230 capture failures, induced in 115 patients in both supine and sitting upright positions, were all promptly recognized by real-time TVI analysis (100% sensitivity). The procedure was never interrupted by the physician, as the automatic energy regulation ensured full patient's safety. The pulse energy was then set at 4 times the threshold to test the alarm specificity during daily activity (sitting, standing up, and walking). The median prevalence of false alarms was 0.336%. The study shows that TVI-based ejection assessment is a valuable approach to the verification of pacing reliability and the autoregulation of ventricular stimulation energy.

No MeSH data available.


Related in: MedlinePlus