Segment Length in Cine Strain Analysis Predicts Cardiac Resynchronization Therapy Outcome Beyond Current Guidelines
Alwin Zweerink1, Daniel J Friedman2, Igor Klem3
1Department of Cardiology, and Amsterdam Cardiovascular Sciences (ACS) (A.Z., C.V., P.S.B., A.C.v.R., C.P.A., R.N.), Amsterdam University Medical Center, location VU Medical Center, Amsterdam, The Netherlands.
Insights
Cardiac resynchronization therapy (CRT) outcomes can be predicted using the segment length in cine strain analysis of the septum (SLICE-ESSsep). A positive SLICE-ESSsep indicates a better prognosis for patients receiving CRT, including those with a class II indication.
Area of Science:
- Cardiology
- Medical Imaging
- Biomedical Engineering
Background:
- Cardiac resynchronization therapy (CRT) benefits are well-established for Class I patients, but outcomes for Class II patients are variable, necessitating improved patient selection.
- The segment length in cine strain analysis of the septum (SLICE-ESSsep) is a novel measurement from cardiac magnetic resonance (CMR) cine imaging that predicts left ventricular functional recovery post-CRT.
- The prognostic value of SLICE-ESSsep for long-term clinical outcomes after CRT remains uninvestigated.
Purpose of the Study:
- To evaluate the prognostic significance of SLICE-ESSsep in predicting clinical outcomes following CRT implantation.
- To determine if SLICE-ESSsep can refine patient selection for CRT, particularly in the heterogeneous Class II patient group.
Main Methods:
- Two hundred eighteen patients with left bundle branch block or intraventricular conduction delay and Class I or II CRT indications were retrospectively analyzed.
- Preimplantation CMR cine imaging was used for manual measurement of SLICE-ESSsep.
- The primary endpoint was a composite of all-cause mortality, left ventricular assist device implantation, or heart transplantation, with secondary endpoints including appropriate implantable cardioverter defibrillator therapy and heart failure hospitalization.
Main Results:
- 65% of patients exhibited a positive SLICE-ESSsep (≥0.9%), indicating systolic septal stretching.
- During a median follow-up of 3.8 years, patients with a positive SLICE-ESSsep showed a significantly lower risk of the primary composite endpoint (HR 0.36, P<0.001) and heart failure hospitalization (HR 0.41, P=0.019).
- In Class II patients, a positive SLICE-ESSsep was associated with clinical outcomes comparable to those of Class I patients, suggesting its utility in this subgroup.
Conclusions:
- SLICE-ESSsep derived from CMR cine imaging is a valuable prognostic marker for clinical outcomes after CRT.
- Identifying patients with a positive SLICE-ESSsep, especially within the Class II indication group, can predict improved CRT response and outcomes.
- Patients with a negative SLICE-ESSsep demonstrate a poorer prognosis, highlighting the need for careful consideration before CRT implantation.
Background:
Patients with a class I recommendation for cardiac resynchronization therapy (CRT) are likely to benefit, but the effect of CRT in class II patients is more heterogeneous and additional selection parameters are needed in this group. The recently validated segment length in cine strain analysis of the septum (SLICE-ESSsep) measurement on cardiac magnetic resonance cine imaging predicts left ventricular functional recovery after CRT but its prognostic value is unknown. This study sought to evaluate the prognostic value of SLICE-ESSsep for clinical outcome after CRT.
Methods:
Two hundred eighteen patients with a left bundle branch block or intraventricular conduction delay and a class I or class II indication for CRT who underwent preimplantation cardiovascular magnetic resonance examination were enrolled. SLICE-ESSsep was manually measured on standard cardiovascular magnetic resonance cine imaging. The primary combined end point was all-cause mortality, left ventricular assist device, or heart transplantation. Secondary end points were (1) appropriate implantable cardioverter defibrillator therapy and (2) heart failure hospitalization.
Results:
Two-thirds (65%) of patients had a positive SLICE-ESSsep ≥0.9% (ie, systolic septal stretching). During a median follow-up of 3.8 years, 66 (30%) patients reached the primary end point. Patients with positive SLICE-ESSsep were at lower risk to reach the primary end point (hazard ratio 0.36; P<0.001) and heart failure hospitalization (hazard ratio 0.41; P=0.019), but not for implantable cardioverter defibrillator therapy (hazard ratio, 0.66; P=0.272). Clinical outcome of class II patients with a positive ESSsep was similar to those of class I patients (hazard ratio, 1.38 [95% CI, 0.66-2.88]; P=0.396).
Conclusions:
Strain assessment of the septum (SLICE-ESSsep) provides a prognostic measure for clinical outcome after CRT. Detection of a positive SLICE-ESSsep in patients with a class II indication predicts improved CRT outcome similar to those with a class I indication whereas SLICE-ESSsep negative patients have poor prognosis after CRT implantation.
