Pulmonary Artery Diameter (PAD) and the Pulmonary Artery to Aorta Ratio (PAD/AAD) as Assessed by Non-contrast Cardiac CT: The Association with Left Ventricular (LV) Remodeling and the LV Function

Abstract

Objective Dilatation of the pulmonary artery itself (PAD: pulmonary artery diameter) or in relation to the ascending aorta (PAD/AAD: pulmonary artery diameter to ascending aortic diameter ratio) has been reported to be associated with pulmonary hypertension and with a prognostic outcome of either heart failure or cardiovascular events. We herein aimed to assess the correlations between pulmonary hypertension-related parameters PAD (or PAD/AAD) and left ventricular (LV) remodeling and LV function. Methods This retrospective study included 193 patients (ages: 67±12 years) who underwent both coronary CT angiography (CCTA) and echocardiography. The PAD and the AAD were measured on a transaxial non-contrast CCTA image at the level of the pulmonary artery bifurcation. Left ventricular mass (LVM), relative wall thickness ratio (RWT), left ventricular ejection fraction (LVEF), left atrial volume (LAV), and early mitral inflow velocity to mitral annular early diastolic velocity ratio (E/e') were evaluated by echocardiography. The relationships between PAD (or PAD/AAD) and echocardiography parameters were assessed, and adjusted for the demographic data and cardiovascular disease (CVD) risk factors by a multivariable linear regression analysis. Results PAD (mean±SD: 2.6±0.4 cm) was positively correlated with LVM (r=0.34, p＜0.001), LAV (r=0.41, p＜0.001), and E/e' (r=0.29, p＜0.001). PAD/AAD (mean±SD: 0.76±0.12 cm) was positively correlated with LVM (r=0.12, p=0.09), LAV (r=0.24, p＜0.001), and E/e' (r=0.15, p=0.04). These correlations remained significant after adjusting for demographic data and CVD risk factors. PAD (or PAD/AAD) did not correlate with LVEF or RWT (p＞0.05). Conclusion Greater PAD or PAD/AAD is significantly associated with LV remodeling and an impaired LV function.

The impact of pulmonary artery to ascending aorta diameter ratio progression on the prognosis of NSCLC patients treated with immune checkpoint inhibitors

“…This view can be confirmed in the study of Nguyen-Thu et al. ( 21 ). In their study, 193 Asian patients with clinical indications for the assessment of cardiovascular disease (CVD) or the cardiac function who underwent both coronary CT angiography (CCTA) and echocardiography had the baseline PAD/AoD ratio of 0.76 ( ± 0.12), which was similar to our study.…”

“…Previous studies have demonstrated that PAD/AoD ≥1 was highly associated with pulmonary hypertension ( 44 ). PAD and AoD reflect pulmonary arterial pressure and heart function ( 21 , 25 , 45 , 46 ). The expansion of the PAD/AoD ratio is a comprehensive manifestation of cardiovascular dysfunction, such as pulmonary vascular inflammation and decreased right heart function, which leads to increased pulmonary arterial pressure and luminal dilation and/or reduced aortic pressure and luminal constriction.…”

“…In the study of Nguyen-Thu et al. ( 21 ), higher PAD/AoD ratio was a potential risk factor for higher left ventricular mass (LVM) (Beta: 67.27 [SE, 30.534]; P = 0.03), left atrial volume (LAV) (Beta: 34.23 [SE, 10.23]; P < 0.001), and early mitral inflow velocity to mitral annular early diastolic velocity ratio (E/e’) (Beta: 5.08 [SE, 2.47]; P = 0.04), which were associated with worse cardiac function. Excessive activation of the immune system by ICIs can lead to immune cell infiltration of the myocardium and myocardial oxidative stress, resulting in reduced cardiac function.…”

“…As a measurable imaging marker that can be obtained in chest computed tomography (CT) images, the pulmonary artery to ascending aorta diameter (PAD/AoD) ratio is highly correlated with the pulmonary arterial pressure obtained by right heart catheterization, and its increase is a potential feature of PAH ( 16 – 18 ). It is also closely related to the change of cardiac structure and function ( 19 – 21 ). Recent studies found that the use of ICIs is associated with the enlargement of PAD and a consequent increase in the PAD/AoD ratio ( 22 , 23 ).…”

Aortic root diameter, main pulmonary artery diameter/aortic root diameter and pericardial fat volume as predictors of occlusive coronary artery disease

“…Thus, using MPAd/ARD ratio might provide an internal standardization and show the overall interaction of different risk factors influencing the prognosis of the cardio-respiratory system [16]. Moreover, both MPAd and ARD can be measured on just one axial slice at the site of pulmonary artery bifurcation [17]. The common embryonic origin and similarity in the remodeling process involving the arterial wall of MPA and the proximal aorta may explain the clinical use of both arteries as a diagnostic or prognostic tool in pathologic processes related to the cardio-respiratory system [16,18].…”