Incremental role of CT coronary angiography in the assessment of left ventricular diastolic function

OBJECTIVE: To determine whether Computed Tomography (CT) coronary angiography (CTCA) has clinical value for the assessment of left ventricular (LV) diastolic dysfunction (DD) beyond traditional information on coronary artery anatomy. METHOD: In this retrospective study, a consecutive group of 72 patients (mean age 59±13 years)—who met the eligibility criteria of sinus rhythm, no significant valvular abnormalities, and who had transthoracic echocardiogram (TTE)—were analysed. The CTCA was prospectively triggered during diastole. Outcomes of interest were CTCA derived LV and left atrial (LA) volumes, diastolic expansion (DE) index: LV volume÷LA volume and DE fraction (DEF): [(LV volume–LA volume)÷LV volume]×100. TTE-LA volume was measured as maximum, minimum and pre-A. Studied patients were divided according to the current classification of LVDD as a reference standard. A small subgroup of nine patients underwent further invasive cardiac catheterisation. RESULTS: CTCA-LV and LA volumes were larger compared with TTE, 37%±20% and 11%±21%, respectively. CTCA-LA volume correlated well with all TTE-LA volumes (maximum: R(2)=0.58; pre-A wave: R(2)=0.39; minimum: R(2)=0.26; p<0.0001) with the smallest differences in maximum LA volume (9±32 mL; mean±2 SD). The DE and DEF correlated with both LA function and LVDD. DE >1.65 and DE <1.40 have good specificity (85% and 88%, respectively), and positive predictive value to differentiate LVDD. DE and DEF were dependent on the patients’ age but independent of other variables. CONCLUSIONS: CTCA derived diastasis volume indices can provide additional quantifiable information on LVDD.