Fig. 1Details of 81 patients who underwent adrenal venous sampling followed by surgery. ACTH, adrenocorticotropic hormone; AVS, adrenal venous sampling; LR, lateralization ratio; CR, contralateral ratio.
Table 1Characteristics of the Patients Who Underwent Adrenalectomy for Primary Aldosteronism
![enm-33-355-i001.jpg]()
Variable |
Value |
Age, yr |
52.8±1.3 |
Sex, male/female |
22 (55)/18 (45) |
Ethnicity, Chinese/Indian/Malay |
36 (90)/2 (5)/2 (5) |
Indication for screening aldosterone |
|
Hypertension and hypokalemia |
32 (80) |
Adrenal incidentaloma |
6 (15) |
Young hypertension |
2 (5) |
Poorly controlled hypertension |
0 |
No. of antihypertensives |
|
1 |
13 (32.5) |
2 |
17 (42.5) |
3 |
8 (20) |
4 |
2 (5) |
Duration of hypertension, yr |
6.5±6.2 |
Mean serum potassium level, mmol/L |
2.9±0.1 |
Basal aldosterone level, pmol/L |
962.8±90.6 |
Basal plasma renin activity, μg/L/hr |
0.17±0.03 |
Basal aldosterone-to-renin ratioa (n=32) |
364.4±84.9 |
Lateralization ratio (n=18) |
14.8±4.9 |
Contralateral ratio (n=27) |
0.35±0.05 |
Site of adrenal mass on CT scan |
|
Left adrenal mass |
24 (60) |
Right adrenal mass |
13 (32.5) |
Bilateral adrenal masses |
3 (7.5) |
Normal CT scan |
0 |
Table 2Factors Associated with Resolution of Hypertension After Adrenalectomy in Patients with Primary Aldosteronism
![enm-33-355-i002.jpg]()
Variable |
Resolution of hypertension after adrenalectomy (n=17) |
No resolution of hypertension after adrenalectomy (n=23) |
P value |
Age, yr |
51.3±2.1 |
53.9±1.8 |
0.3 |
Ethnicity |
|
|
0.4 |
Indian (n=2) |
0 |
2 (100) |
Chinese (n=36) |
16 (44.4) |
20 (55.6) |
Malay (n=2) |
1 (50.0) |
1 (50.0) |
BMI, kg/m2
|
25.4±0.8 |
25.7± 0.7 |
0.7 |
Duration of HTN, yr |
3.8±0.8 |
8.5±1.5 |
0.02 |
Potassium level, mmol/L |
2.9±0.2 |
2.9±0.1 |
0.8 |
Preoperative PRA, μg/L/hr |
0.2±0.05 |
0.1±0.03 |
0.06 |
Preoperative PAC, pmol/L |
983.3±125.4 |
947.7±129.8 |
0.8 |
Mean LR (n=18) |
8.0±2.5 (n=9) |
21.7±9.3 (n=9) |
0.1 |
Mean CR (n=27) |
0.36±0.20 (n=13) |
0.34±0.09 (n=14) |
0.8 |
CR level |
|
|
1.0 |
≤0.5 (n=20) |
10 (50.0) |
10 (50.0) |
>0.5 (n=7) |
3 (42.9) |
4 (57.1) |
Components of ARS |
|
|
|
No. of anti-HTN meds ≤2 (2 points) |
|
|
0.09 |
≤2 (n=30) |
15 (50.0) |
15 (50.0) |
>2 (n=10) |
2 (20.0) |
8 (80.0) |
BMI ≤25 kg/m2 (1 point) |
|
|
0.3 |
≤25 (n=15) |
8 (53.3) |
7 (46.7) |
>25 (n=25) |
9 (36.0) |
16 (64.0) |
Duration of HTN ≤6 yr (1 point) |
|
|
0.03 |
≤6 (n=23) |
13 (56.5) |
10 (43.5) |
>6 (n=17) |
4 (23.5) |
13 (76.5) |
Female sex (1 point) |
|
|
0.3 |
Female (n=18) |
9 (50.0) |
9 (50.0) |
Male (n=22) |
8 (36.4) |
14 (63.6) |
ARS |
|
|
0.004 |
0–2 (n=12) |
1 (8.3) |
11 (91.7) |
3–5 (n=28) |
16 (57.1) |
12 (42.9) |
Mean ARS |
3.5±0.3 |
2.5±0.3 |
0.02 |
Table 3Rates of Resolution and Improvement of Hypertension in Patients in Whom a Contralateral Ratio <1 Was Used to Assist in the Decision for Adrenalectomy
![enm-33-355-i003.jpg]()
Group |
Details of patients who underwent adrenalectomy |
Hypertension resolution rate of patients who underwent adrenalectomy guided by a positive CR |
Improvement rate (including resolution rate) of patients who underwent adrenalectomy guided by a positive CR |
Mean CR of the patients who underwent adrenalectomy (range) |
Group A (positive LR and CR) |
13 of 20 patients underwent adrenalectomy. The decision for surgery was guided by a positive CR and LR. |
6/13 (46%) |
13/13 (100%) |
0.27 (0.02–0.8) |
Group B (positive CR and negative LR) |
5 of 8 patients underwent adrenalectomy. The decision for surgery in all 5 cases was guided by a positive CR. |
3/5 (60%) |
4/5 (80%) |
0.43 (0.14–0.76) |
Group E (invalid LR or CR) |
4 of 10 patients underwent adrenalectomy. The de- cision for surgery in 3 of the 4 cases was guided by a positive CR because the LR was invalid. |
1/3 (33.3%) |
3/3 (100%) |
0.55 (0.11–0.95) |
Unsuccessful AVS (failed either one or both adrenal vein cannu lations) |
18 out of 35 patients underwent adrenalectomy. The decision for operation in 7 of the adrenalec- tomy cases was guided by a positive CR. |
3/7 (42.8%) |
6/7 (85.7%) |
0.42 (0.13–0.98) |
Total |
28 patients underwent adrenalectomy guided by a positive CR. |
13/28 (46%) |
26/28 (92.9%) |
0.42 (0.02–0.98) |