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Objective:To analyze the late gadolinium enhancement (LGE) manifestations, cardiac function, and myocardial strain by feature tracking (FT) in Takayasu arteritis (TA) with pulmonary artery involvement (PTA) using cardiac MR (CMR), and then to investigate manifestations of the impaired myocardial structure and function.Methods:A retrospective study was performed on 32 patients with PTA and 21 healthy subjects without cardiopulmonary diseases from January 2017 to December 2020. All of them underwent CMR examinations. According to the presence of pulmonary arterial hypertension (PAH),PTA patients were divided into two groups including PAH group (11 cases) and non-PAH group (21 cases). LGE manifestations were observed and Fisher exact test was used for statistical analysis between the two groups. Cardiac function parameters and FT values including global peak strain of the left and right ventricle were calculated separately in PAH, non-PAH group of patients and healthy controls, using One-way ANOVA or non-parametric Kruskal-Wallis test for statistical analysis including a pairwise comparison between groups. The correlations between FT values of the PAH group and parameters measured by right heart catheterization test (RHC) and transthoracic echocardiography were analyzed using Pearson or Spearman correlation analysis.Results:There were 23 PTA patients (71.9%) with LGE. LGE in the interventricular insertion points (IPs)(11/11), and in the mid-wall (11/11) or epicardial (10/11) myocardium was more common ( P values were 0.006,<0.001 and 0.011, respectively) in PAH group, compared with LGE in the IPs (11/21), and in the mid-wall (7/21) or epicardial (9/21) myocardium in non-PAH group. The absolute values of left ventricular global peak circumferential strain (LVGPCS), left ventricular global peak longitudinal strain (LVGPLS) and right ventricular global peak longitudinal strain in PAH group were smaller than those in healthy subjects ( P<0.05). The absolute values of LVGPCS and LVGPLS in non-PAH group were smaller than those in healthy subjects ( P<0.05). In PAH group, mean pulmonary artery pressure of RHC was correlated with several FT parameters ( P<0.05), especially left ventricular global peak radial strain ( r=-0.807, P=0.009) and LVGPCS ( r s=0.817, P=0.007). Conclusions:Myocardial injury can be seen in PTA patients. And LGE in the IPs and LGE in the mid-wall or epicardial myocardium is more common in PTA patients with PAH. LVGPCS and LVGPLS can early indicate left heart dysfunction in PTA patients without PAH.
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Objective:To explore the relationship between the imaging features of enhanced MRI in patients with central chronic pulmonary artery thromboembolism (CPTE) and pulmonary vascular resistance (PVR).Methods:Thirty-nine patients with CPTE who had contrast-enhanced MRI examination were retrospectively enrolled this study from January 2018 to December 2020. And 33 patients who received right heart catheterization were divided into two groups based on PVR=1 000 dyn·s·cm -5. The differences of imaging features of CPTE in enhanced MRI between the two groups were compared. The relationship between gender, duration of disease, age, pleural thickening, bilateral bronchial artery dilation, number of the involved vascular segments, number of thrombosis, number of the thrombus-related delayed enhancement of artery wall and PVR was analyzed by binary logistic regression. Results:In 39 patients with central CPTE, the dilated lumen (168, 43.30%) and delayed enhancement of wall (122, 31.52%) were found in most of pulmonary arteries. The rate of the lumen dilatation associated with thrombus was the highest among that of the lumen abnormality (66, 52.80%). There were more thrombi in PVR<1 000 dyn·s·cm -5 group than those in PVR≥1 000 dyn·s·cm -5 group (χ 2=9.55, P=0.002). There was no significant difference in the incidence of wall delayed enhancement associated the thrombus between the two groups (χ 2=0.90, P=0.344). The incidence of bilateral bronchial arterial dilatation in PVR<1 000 dyn·s·cm -5 group was higher than that in PVR≥1 000 dyn·s·cm -5 group ( P=0.019). Logistic regression analysis showed that female, the less number of involved vascular segments and bilateral bronchial artery dilation were correlated with the lower PVR. Conclusions:Enhanced MRI is helpful to accurately evaluate the lumen abnormality of pulmonary artery and wall remodeling in central CPTE, which is of great value for the assessment of patients′ conditions and treatment effect.
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Objective To compare the blood flow characteristics of the proximal pulmonary arteries in patients with chronic thromboembolic pulmonary hypertension (CTEPH) and idiopathic pulmonary arterial hypertension (IPAH) by 3.0T PC-MRI. Methods Twenty seven patients with pulmonary arterial hypertension (7 IPAH patients and 20 CTEPH patients) were prospectively included. Twenty healthy volunteers were enrolled as the control group. All subjects underwent PC-MRI. PC-MRI derived parameters included peak, mean velocity and mean flow of main pulmonary artery (MPA), left/right pulmonary artery (LPA/RPA), left/right interlobar pulmonary artery (LIPA/RIPA). Right heart catheterization was performed in patients with pulmonary arterial hypertension. The parameters among CTEPH, IPAH group and control group were compared by one way analysis of variance. Results There were significant differences for peak velocity, mean velocity and mean flow among CTEPH, IPAH group and control group (F=4.13—102.81, all P<0.05). There was significant difference for peak velocity in RPA between CTEPH[(32.0 ± 7.8)cm/s] and IPAH group[(50.0±15.0)cm/s]. There was no difference for mean velocity between CTEPH and IPAH group. The mean flow between CTEPH and IPAH group was statistically different[MPA: (74.3 ± 20.8) ml/s versus (61.3±16.7) ml/s, LPA:(29.3±12.7) ml/s versus (23.2±11.2) ml/s, RPA:(43.5±17.4) ml/s versus (56.8±13.5) ml/s, LIPA: (19.2 ± 8.0) ml/s versus (12.1 ± 5.8) ml/s, all P<0.05]. Conclusion There is significantly different characteristics for the hemodynamics of the proximal pulmonary arteries between CTEPH group and IPAH group. 3.0T PC-MRI may effectively detect the pulmonary hemodynamic changes.
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Objective To evaluate the lung V/Q imaging in the diagnosis of chronic thromboembolic pulmonary hypertension (CTEPH).Methods Seventy-six patients (46 males,30 females,age 27-84 y) with clinically suspected CTEPH who had undergone lung V/Q imaging,CT pulmonary angiography (CTPA),pulmonary angiography (PA) and right heart cardiac catheterization were studied.The sensitivity,specificity,accuracy,positive predictive value and negative predictive value of lung V/Q imaging in detecting CTEPH were calculated and compared with those of CTPA.The x2 test was used for statistical analysis with SPSS 11.5.The distribution of involvement of segments in 47 patients with CTEPH was analyzed.Results Forty-seven patients had a final diagnosis of CTEPH and 29 had non-CTEPH etiology.The sensitivity,specificity,accuracy,positive predictive value and negative predictive value of lung V/Q imaging were 97.9％ (46/47),86.2％ (25/29),93.4％ (71/76),92.0％ (46/50) and 96.2％ (25/26),while those of CTPA were 78.7％ (37/47),93.1％ (27/29),84.2％ (64/76),94.9％ (37/39) and 73.0％ (27/37),respectively.The sensitivity (x2 =5.818,P=0.012) and negative predictive value (x2 =5.693,P =0.017) for lung V/Q imaging were significantly higher than those of CTPA.V/Q imaging could identify patients with CTEPH from those with idiopathic PAH and familial PAH based on the almost normal ventilation imaging.The lung perfusion SPECT imaging detected 585 (62.2％) of involved segments among 940 segments in 47 patients with CTEPH,with an average of 12.4 involved segments in each patient.The number of involved segments in the right lung was significantly higher than that in the left lung (36.2％ (340/940) vs 26.1％ (245/940) ; x2 =40.85,P＜0.01).Conclusions Lung V/Q imaging plays an important role in diagnosis of CTEPH and in identification of CTEPH from other types of PAH.A normal V/Q imaging can effectively exclude CTEPH.In addition,V/Q imaging can provide more diagnostic information in patients with a clinical suspicion of CTEPH who had negative results by CTPA and PA.
