CMR-based left atrial strain for predicting left ventricular diastolic dysfunction in asymptomatic hypertensive...

Area of Science:

• Cardiovascular Imaging
• Cardiac Magnetic Resonance (CMR)
• Diastolic Dysfunction Assessment

Background:

• Left ventricular diastolic dysfunction (LVDD) is common in hypertension (HTN) and linked to heart failure with preserved ejection fraction (HFpEF).
• Standard CMR protocols lack hemodynamic parameters for diastolic function, limiting LVDD evaluation.
• CMR feature tracking (CMR-FT) offers a potential solution for assessing left atrial (LA) function in subclinical HTN.

Purpose of the Study:

• To validate CMR-FT-derived LA strain as a marker for detecting LVDD with elevated left atrial pressure (LAP) in HTN patients.
• To provide CMR parameters for diastolic dysfunction assessment without requiring extra scanning time.

Main Methods:

• Retrospective study of 152 HTN patients and 60 controls, including echocardiography and CMR.
• Stratification of HTN patients into normal LAP and elevated LAP groups based on LVDD severity.
• Quantification of LA strain (reservoir, conduit, pump) using CMR-FT, with statistical comparisons and ROC analysis for diagnostic performance.

Main Results:

• Significant impairment in LA reservoir strain (εs) and conduit strain (εe) was observed in HTN groups compared to controls.
• Booster pump strain (εa) was reduced in the elevated LAP group.
• LA strain parameters, particularly εs (cutoff 29.55%, AUC 0.896), effectively discriminated elevated LAP; combined εs + LAVImin (AUC 0.919) showed superior accuracy.

Conclusions:

• CMR-derived LA strain is a powerful, non-invasive marker for identifying cardiac impairment and LVDD with elevated LAP in HTN patients.
• LA strain and minimum LA volume index (LAVmin) show promise for routine diastolic function assessment in clinical CMR.