Abstract 16364: Improvement of Left Ventricular Ejection Fraction After Cardiac Resynchronization Therapy Can Be Predicted Based on Biventricular Capture on Electrocardiogram
Background: CRT is associated with reduced morbidity and mortality. Predicting the approximately 30% of patients who will be non-responders to BiV pacing remains challenging. Ammann et al (Ann Intern Med, June 2005) published clear ECG criteria to assess BiV capture. We assessed whether the Ammann criteria on the first post-procedural ECG correlated with improvement of left ventricular ejection fraction (EF).
Methods: A retrospective chart review was conducted on all patients who had a CRT device implanted at UNC Hospitals between April 2008 and December 2011. Patients without a post-implant ECG or echocardiogram within 3 years were excluded. Improvement of EF was defined as net improvement of EF ≥ 7.5% (Hsu et al, JACC, June 2012). BiV capture was predicted based on Ammann’s ECG criteria (R/S ≥ 1 in V1 or R/S ≤ 1 in lead I). Chi square and t-tests were used for analysis.
Results: Of 130 patients who underwent CRT, 72 patients were included for analysis. The ECG criteria for BiV capture were met by 54 patients (75%). Improvement of EF was seen in 63% of patients who met the ECG criteria. Only 28% of patients who did not meet the criteria showed an improved EF. The sensitivity and specificity of the ECG criteria to predict EF improvement were 87% and 40%, respectively. Improvement of EF was statistically significantly associated with BiV capture on the first post-procedural ECG (X2=6.73, p<0.01). The average improvement of EF was 12.8% (CI, 12 to 13.6) for patients who had BiV capture and 5.3% (CI, 4.4 to 6.1) for patients who did not (p=0.01).
Conclusions: A single post-procedural ECG is able to predict responders and non-responders in regards to the improvement of EF over the next three years. In addition, average improvement of EF in patients with BiV capture was significantly greater. This gives the clinician an easy to use tool to assess the success of the procedure and it highlights the importance of intra-procedural ECG analysis of LV wall capture to optimize response to BiV pacing.
- © 2013 by American Heart Association, Inc.