Myocardial strain-curve deformation patterns after Fontan operation.

Area of Science:

• Cardiology
• Medical Imaging
• Biomedical Engineering

Background:

• Cardiac MRI (CMR) is crucial for assessing systolic function in Fontan circulation.
• Global circumferential and longitudinal strain (GCS and GLS) quantify myocardial deformation and predict clinical events.
• Understanding temporal deformation patterns can offer deeper insights beyond peak strain values.

Purpose of the Study:

• To apply Principal Component Analysis (PCA) to myocardial strain-time curves in Fontan patients.
• To identify latent strain features and their relationship with clinical outcomes.
• To investigate differences in strain patterns between single left ventricle (SLV) and single right ventricle (SRV) morphologies.

Main Methods:

• Retrospective analysis of CMR data from 122 patients post-Fontan operation.
• Application of PCA to strain-time curves to derive shape scores.
• Cox regression analysis to correlate CMR variables and PCA-derived scores with clinical outcomes (death, transplant, etc.).

Main Results:

• PCA identified 3 primary modes of strain-curve variation: amplitude, time-to-peak strain, and post-systolic slope.
• In SLV patients, GCS was the sole CMR predictor of clinical events.
• In SRV patients, indexed volumes, GCS, GLS, and their respective PCA component scores were significant predictors of clinical events.

Conclusions:

• CMR-derived global strain measures are sensitive indicators of clinical outcomes in Fontan circulation.
• Myocardial strain-time curve morphology, analyzed by PCA, provides valuable prognostic information, especially in SRV patients.
• This technique enhances risk stratification for patients with Fontan physiology.