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A new simplified electrocardiographic score predicts clinical outcome in patients treated with CRT
Eszter M Végh1,2, Jagdesh Kandala1, Lukasz Januszkiewicz1,3
1Cardiology Division, Arrhythmia Service, Massachusetts General Hospital, 55 Fruit Street, Boston, MA 02114-2750, USA.
Insights
A simple electrocardiogram (ECG) score can predict patient response to Cardiac Resynchronization Therapy (CRT). This ECG scoring system helps identify patients likely to benefit from CRT, improving clinical outcomes and event-free survival.
Area of Science:
- Cardiology
- Medical Imaging
- Predictive Analytics
Background:
- Cardiac Resynchronization Therapy (CRT) improves outcomes in heart failure patients with wide QRS complexes.
- A significant portion of patients (up to 1/3) do not respond to CRT.
- Predicting CRT response is crucial for optimizing patient management.
Purpose of the Study:
- To evaluate a simple electrocardiogram (ECG)-based scoring system for predicting clinical outcomes in CRT recipients.
- To determine if specific ECG parameters can identify CRT responders versus non-responders.
Main Methods:
- A cohort of 491 CRT patients was analyzed over a 3-year follow-up period.
- Three post-implant ECG parameters (QRS duration, intrinsicoid deflection time in V1, and amplitude change in V1) were measured.
- A numerical score (0-3) was created based on these ECG variables.
Main Results:
- Shortening of QRS duration ≥20ms, a ≥50% decrease in summed R+S amplitude in V1, and ≤40ms intrinsicoid deflection time in V1 independently predicted event-free survival.
- The total ECG score was a significant independent predictor of event-free survival (HR 0.65) and left ventricular ejection fraction improvement (OR 1.7).
Conclusions:
- A simple, composite 12-lead ECG score derived from post-implant measurements can effectively predict long-term clinical outcomes in patients receiving CRT.
- This ECG-based scoring system offers a valuable tool for assessing CRT response and guiding patient care.
Aims:
Cardiac Resynchronization Therapy (CRT) reduces morbidity and mortality for patients with heart failure and wide QRS complex, but up to 1/3 of patients are "non-responders" to the therapy. This study examines the ability of a simple standard electrocardiogram (ECG)-based scoring system to predict clinical outcome.
Methods And Results:
Four hundred and ninety-one consecutive patients with CRT-implants (79% males, mean age 71 years, LVEF 24%, 59% with ischemic cardiomyopathy, 83% in NYHA class III) were included from a single large volume centre. All patients met standard indications for CRT, and were followed for 3 years after CRT implantation. Three ECG parameters were measured on the post-implant ECG, and compared to pre-implantation measurements: QRS duration, time to intrinsicoid deflection onset (ID) in V1 lead, amplitude change in V1 lead. Each positive ECG variable was given a numerical value of 1 to create the score (ranging 0-3). Clinical outcome was assessed as a composite of all-cause death, left ventricular assist device implantation, cardiac transplantation and HF hospitalization. Event-free survival was predicted by shortening of QRS duration ≥20 ms (HR 0.66 [95% CI 0.48-0.90] P = 0.009), ≥50% decreased summed R + S amplitude in V1 lead (HR 0.67 [0.49-0.90] P = 0.009) and ≤40 msec ID time in lead V1 during pacing (HR 0.63 [0.46-0.86] P = 0.004). The total score was an independent predictor for both event-free survival (HR 0.65 [0.54-0.77] P < 0.001) and for ≥10% left ventricular ejection fraction improvement (OR 1.7 [1.3-2.3] P < 0.001).
Conclusions:
Composite data from 12-lead ECG during CRT-treatment can be used in a simple score to predict long-term clinical outcome.
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