An Electrocardiogram-Based Algorithm To Detect Loss of Left Ventricular Capture during Cardiac Resynchronization Therapy

21 June 2005 | Volume 142 Issue 12 Part 1 | Pages 968-973

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.

Editors' Notes Context Cardiac resynchronization therapy using biventricular pacing can improve heart failure in selected patients. Worsening heart failure in such patients may be due to failure to pace both ventricles, but this diagnosis is difficult to make without using a programming device. Contribution This study identifies a highly sensitive (93%) and specific (94%) algorithm for using 12-lead electrocardiography to identify loss of left ventricular pacing. Cautions In the study, cardiologists evaluated the electrocardiograms. The algorithm may be less accurate in the hands of noncardiologists. –The Editors

 

Author and Article Information

From University Hospital, Basel, and Kantonsspital St. Gallen, St. Gallen, Switzerland; and Herz-Zentrum Bad Krozingen, Bad Krozingen, Germany.

Note: Drs. Ammann and Sticherling contributed equally to this research.

Potential Financial Conflicts of Interest: None disclosed.

Requests for Single Reprints: Peter Ammann, MD, Department of Internal Medicine, Division of Cardiology, Kantonsspital St. Gallen, CH-9007 St. Gallen, Switzerland; e-mail, peter.ammann{at}kssg.ch.

Current Author Addresses: Dr. Ammann: Department of Internal Medicine, Division of Cardiology, Kantonsspital St. Gallen, CH-9007 St. Gallen, Switzerland.

Drs. Sticherling, Eckstein, Bernheim, Schaer, and Osswald: Division of Cardiology, University Hospital, CH-4031 Basel, Switzerland.

Dr. Kalusche: Herz-Zentrum Bad Krozingen, D-79189 Bad Krotzingen, Germany.

Author Contributions: Conception and design: P. Ammann, C. Sticherling, S. Osswald.

Analysis and interpretation of the data: P. Ammann, C. Sticherling, S. Osswald, B. Schaer, A. Bernheim, D. Kalusche, J. Eckstein.

Drafting of the article: P. Ammann, C. Sticherling, S. Osswald, B. Schaer, D. Kalusche.

Critical revision of the article for important intellectual content: P. Ammann, C. Sticherling, S. Osswald, B. Schaer.

Final approval of the article: P. Ammann, C. Sticherling, S. Osswald, B. Schaer, A. Bernheim, D. Kalusche, J. Eckstein.

Provision of study materials or patients: C. Sticherling, S. Osswald, B. Schaer.

Statistical expertise: C. Sticherling, S. Osswald.

Obtaining of funding: S. Osswald.

Administrative, technical, or logistic support: C. Sticherling, S. Osswald, B. Schaer, J. Eckstein.

Collection and assembly of data: P. Ammann, C. Sticherling, S. Osswald, B. Schaer, A. Bernheim, D. Kalusche, J. Eckstein.