Transverse strain predicts exercise capacity in systemic right ventricle patients

Area of Science:

• Cardiology
• Echocardiography
• Congenital Heart Disease

Background:

• Patients with transposition of great arteries (TGA) after atrial switch (AS) repair often develop asymptomatic ventricular dysfunction years before heart failure.
• Early detection of systemic right ventricular (RV) dysfunction can guide timely heart failure therapy and enhance patient monitoring.

Purpose of the Study:

• To assess longitudinal and transverse systolic function of the systemic RV in TGA patients post-AS repair using 2D strain.
• To correlate these RV systolic function parameters with patient exercise capacity.

Main Methods:

• Echocardiography and 2D strain analysis were performed on 26 TGA patients post-AS repair and 24 healthy controls.
• Patients underwent treadmill exercise testing using the Bruce II protocol.

Main Results:

• Systemic RVs in TGA patients showed homogeneous reduction in longitudinal strain and increased transverse strain, unlike controls.
• RV transverse strain, particularly in mid and apical segments, was significantly elevated in TGA patients.
• RV transverse 2D strain strongly correlated with and was the best predictor of exercise capacity in AS-TGA patients.

Conclusions:

• Transposition of great arteries (TGA) patients post-atrial switch (AS) repair exhibit a shift towards predominant transverse thickening over longitudinal shortening in the systemic RV.
• Two-dimensional (2D) transverse strain is a key indicator of exercise capacity in these patients.
• Monitoring RV transverse myocardial deformation properties is recommended over solely assessing longitudinal function in AS-TGA patient follow-up.