Relation of subclinical left and right ventricular dysfunctions measured by computed tomography angiography with the severity of coronary artery disease.

Objective: Ventricular dysfunction in asymptomatic patients is directly linked to the eventual development of symptomatic congestive heart failure. This study investigates whether subclinical left ventricular (LV) and right ventricular (RV) dysfunctions measured by computed tomography angiography is associated with the severity of coronary artery disease (CAD).
Methods and Results: We studied 1608 consecutive patients with suspected CAD (age 62 ± 10 years, 64% male), who underwent coronary artery calcium (CAC) scanning and computed tomography angiography. RV and LV volumes at end systole and end diastole were measured, and stroke volume and ejection fraction were calculated using the Simpson method and piecewise smooth subdivision surface (PSSS) method. Analysis by Simpson was performed on short axis and apical four-chamber views. Axial images were used to measure RV and LV volumes by the PSSS method. CAD was defined as normal, nonobstructive, and obstructive (0% stenosis, luminal stenosis 1-49 and 50%+, respectively). There was a strong agreement between PSSS and Simpson method RV ejection fraction (RVEF) and LV ejection fraction (LVEF) measurement. RVEF and LVEF decreased proportionally from CAC 0 to CAC 100+, also from normal-to-diseased coronaries (P=0.001). After adjustment for cardiovascular risk factors, the mean LVEF and RVEF decreased 2.8 and 2.4%, respectively in CAC 100+ compared with CAC 0. Similarly, LVEF and RVEF decreased significantly in nonobstructive CAD (-3.5 and -3.1%, respectively) and obstructive CAD (-5.9 and -4.5%, respectively) compared with normal coronaries, respectively (P<0.05). The relative risk of each 5% decrease in LVEF and RVEF was 1.33 and 1.29 for nonobstructive CAD and 1.54 and 1.33 for obstructive CAD, respectively.
Conclusion: The presence and severity of coronary atherosclerosis is significantly associated with subclinical RV and LV dysfunctions.