Format

Send to

Choose Destination
Ann Intern Med. 2005 Jun 21;142(12 Pt 1):968-73.

An electrocardiogram-based algorithm to detect loss of left ventricular capture during cardiac resynchronization therapy.

Author information

1
University Hospital, Basel, Switzerland. peter.ammann@kssg.ch

Abstract

BACKGROUND:

Loss of left ventricular capture in patients with cardiac resynchronization devices may account for worsening heart failure and can be difficult to diagnose without a programmer.

OBJECTIVE:

To determine whether distinct morphologic changes on the surface electrocardiogram indicate loss of left ventricular capture.

DESIGN:

After analysis of the R-S spike ratio in the 12-lead electrocardiogram during right ventricular and biventricular pacing in 10 patients, an algorithm to detect loss of left ventricular capture was developed.

SETTING:

University hospital.

PATIENTS:

54 patients with a cardiac resynchronization device and underlying left bundle-branch block.

MEASUREMENTS:

Leads V1 and I of a 12-lead electrocardiogram were assessed after biventricular pacing was confirmed and after the device was programmed to right ventricular pacing only (simulating loss of left ventricular capture).

RESULTS:

The sensitivity of the algorithm to correctly identify loss of left ventricular capture was 94% (95% CI, 88.2% to 97.7%), and the specificity was 93% (CI, 86.3% to 95.8%). The likelihood ratio of a positive test result was 12.8 (CI, 6.443 to 23.310), and the likelihood ratio of a negative test result was 0.06 (CI, 0.024 to 0.137).

LIMITATIONS:

The algorithm was tested in patients in whom the right ventricular electrode was placed in the apex of the right ventricle only.

CONCLUSION:

Presence of biventricular capture--the prerequisite for successful cardiac resynchronization therapy--and loss of left ventricular capture can be accurately detected by an algorithm based on analysis of the R-S ratio on leads V1 and I of the surface electrocardiogram.

PMID:
15968011
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Silverchair Information Systems
Loading ...
Support Center