A total of 61 patients was included in this retrospective study, of whom 35 belonged to the CEUS-AVS and 26 to the DSA-AVS group. Table 1 shows the baseline data of all patients. Patient sex, age, diastolic blood pressure, body mass index, number of antihypertensive medications, and lowest serum potassium levels did not differ significantly between the two groups. However, systolic blood pressure was significantly higher in the CEUS-AVS than in the DSA-AVS group.
Table 1
Demographic and endocrine data of all 61 patients
Characteristic | CEUS-AVS group (n = 35) | DSA-AVS group (n = 26) | P value |
Age | 54.86 ± 9.18 | 50.54 ± 7.78 | 0.06 |
Sex (male: female) | 24:11 | 18:8 | 0.96 |
Weight | 71.84 ± 14.37 | 72.77 ± 9.91 | 0.78 |
Height | 165.5 ± 9.66 | 167.3 ± 5.81 | 0.40 |
BMI | 25.77 ± 3.76 | 25.95 ± 2.88 | 0.84 |
SBP (mmHg) | 159.57 ± 21.27 | 149.04 ± 18.49 | 0.05 |
DBP (mmHg) | 90 [80, 105] | 88.46 ± 10.38 | 0.60 |
Number of antihypertensive medications | 2 [2, 3] | 2 (2, 2) | 0.27 |
Serum potassium (mmol/L) | 2.91 ± 0.47 | 3.06 [2.70, 3.59] | 0.58 |
Captopril challenge test | 28.15 [18.35, 35.85] n = 30 | 19.77 ± 10.08 n = 14 | |
Normal saline test | 24.60 [17.00, 34.75] n = 18 | 25.20 [14.20, 33.53] n = 12 | |
Note: The captopril challenge and normal saline tests are used to confirm a diagnosis of PA. In accordance with the Chinese guidelines for the diagnosis and treatment of PA, a confirmed diagnosis of PA is made when the serum aldosterone level is > 10 ng/dL after the normal saline test or the serum aldosterone level is > 11 ng/dL at 2 h after the captopril challenge test. All patients included in the study received a confirmed diagnosis of PA by at least one of the two tests. |
CEUS-AVS, contrast-enhanced ultrasonography-adrenal vein sampling; DSA-AVS, digital subtraction angiography-adrenal vein sampling; PA, primary aldosteronism; BMI, body mass index; SBP, systolic blood pressure; DBP, diastolic blood pressure
A flow chart of the process for right AVS as performed in this study is shown in Fig. 2.
Two cases of unsuccessful right AVS and one case of unsuccessful left AVS occurred in the CEUS-AVS group, while seven cases of unsuccessful right AVS and no cases of unsuccessful left AVS were recorded in the DSA-AVS group. The success rate of right AVS was higher in the CEUS-AVS group than in the DSA-AVS group (94.3% vs. 73.1%, P = 0.03), but the success rates of left AVS and bilateral AVS did not significantly differ between the two groups (97.14% vs. 100%, P = 1.00; 91.43% vs. 73.08%, P = 0.08). In the CEUS-AVS group, five of the blood vessels deemed by the operator to be the adrenal central vein based on DSA were confirmed as AHVs by CEUS (Fig. 3).
Successful adrenal vein re-cannulation was performed in four of the five cases, while the right adrenal vein opening could not be located in the remaining case. In the other unsuccessful right AVS case in the CEUS-AVS group, successful right adrenal vein cannulation was confirmed by CEUS, but a sufficient volume of blood could not be sampled. The success rate of CEUS imaging of the right adrenal vein was 97.1%, and the use of US imaging increased the right AVS success rate from 82.9–94.3%. Ten AVS procedures were unsuccessful, of which nine were right AVS (two in the CEUS-AVS group and seven in the DSA-AVS group). Among the 10 patients who underwent unsuccessful AVS (including one case of unsuccessful left AVS), six patients underwent repeat AVS by other interventionalists. Three of these patients had successful AVS. One patient opted for left adrenalectomy, and three patients refused to undergo repeat AVS. Compared with the DSA-AVS group, the radiation exposure time was shorter in the CEUS-AVS group (8.4 [6.00, 12.3] vs. 15.37 [7.23, 24.75], P = 0.04), but there was no significant difference in operative time (46 [40,61] vs. 57.86 ± 22.45, P = 0.32) (Table 2).
Table 2
AV success rates, exposure times, operative times, and surgery-related complications
Characteristic | CEUS-AVS group (n = 35) | DSA-AVS group (n = 26) | P value | |
Successful right AVS | 33 (2 unsuccessful) | 19 (7 unsuccessful) | 0.03 | |
Successful left AVS | 34 (1 unsuccessful) | 26 (0 unsuccessful) | 1.00 | |
Successful bilateral AVS | 32 (3 unsuccessful) | 19 (7 unsuccessful) | 0.08 | |
Total exposure time | 8.4 [6.00, 12.3] | 15.37 [7.23, 24.75] | 0.04 | |
Operative time | 46 [40, 61] | 57.86 ± 22.45 | 0.32 | |
Venous injury | 5 | 2 | 0.67 | |
CEUS-AVS, contrast-enhanced ultrasonography-adrenal vein sampling; DSA-AVS, digital subtraction angiography-adrenal vein sampling
In terms of adverse effects, 7 of the 61 patients experienced local contrast agent retention in the side wall of the inferior vena cava (five cases in the CEUS-AVS group and two cases in the DSA-AVS group), suggesting possible surgery-related injury to the right adrenal vein or inferior vena cava. One patient in the DSA-AVS group presented with right-sided low back pain, and post-operative CT revealed a hematoma in the right adrenal region, raising the possibility of adrenal vein rupture. The patient was retained in the hospital for further observation, and the pain disappeared after 3 days. No other adverse reactions related to the AVS operations, iodine contrast agent, or US contrast agent were observed. The incidence of surgery-related complications did not significantly differ between the CEUS-AVS and the DSA-AVS group (14.3% vs. 7.7%, P = 0.67) (Table 2).