An Alternative Method for Adrenal Venous Sampling in Cases in Which Right Adrenal Vein Sampling is Difficult

PurposeCatheterization of the right adrenal vein (rt.AdV) to obtain blood samples can often be difficult. The aim of the present study was to investigate whether blood sampling from the inferior vena cava (IVC) at its juncture with the rt.AdV can be an alternative to sampling of blood directly from the rt.AdV.Materials and MethodsThis study included 44 patients diagnosed with primary aldosteronism (PA) in whom AVS with adrenocorticotropic hormone (ACTH) was performed, resulting in a diagnosis of idiopathic hyperaldosteronism (IHA) (n=24), and patients diagnosed with unilateral aldosterone-producing adenoma (APA) (n=20; rt.APA=8, lt.APA=12). In addition to regular blood sampling, blood was also sampled from the IVC, as the substitute rt.AdV [S-rt.AdV]. Diagnostic performance with the conventional lateralized index (LI) and the modified LI using the S-rt.AdV was compared to examine the utility of the modified LI.ResultsThe modified LI of the rt.APA (0.4±0.4) was significantly lower than those of the IHA (1.4±0.7) (p<0.001) and the lt.APA (3.5±2.0) (p<0.001). The modified LI of the lt.APA was significantly higher than those of the IHA (p<0.001) and rt.APA (p<0.001). Sensitivity and specificity to diagnose rt.APA and lt.APA using the modified LI with threshold values of 0.7 and 2.2, respectively, they were 87% and 75%, respectively, and 94% and 94%, respectively.ConclusionThe modified LI has the potential to be an alternative method for rt.AdV sampling in cases in which rt.AdV sampling is difficult. Obtaining the modified LI is extremely simple, which might complement conventional AVS.

11C-metomidate PET CT versus Adrenal Vein Sampling for diagnosing surgically curable primary aldosteronism: prospective test validation, and impact of somatic genotype and ethnicity on outcomes

Primary aldosteronism (PA) due to a unilateral aldosterone-producing adenoma (APA) is a common, curable cause of hypertension, but invasive methods of diagnosis and treatment contribute to <1% of patients being offered the chance of cure. The primary objective of our prospective within-patient study in 143 patients with PA was to compare accuracy of 11C-metomidate (MTO) PET-CT scanning with adrenal vein sampling (AVS) in predicting biochemical cure from PA and resolution of hypertension. Secondary outcomes addressed heterogeneity of underlying pathogenesis and prediction of patients most likely to achieve complete cure of hypertension. 128 patients reached 6-9 month follow-up. 77/78 surgical patients achieved one or more of the four hierarchically analysed Primary Aldosteronism Surgical Outcome (PASO) criteria for biochemical and clinical success. MTO was not superior to AVS but all four differences in accuracy favored MTO, with 95% CIs >-17%, the pre-specified margin of non-inferiority. The best univariate predictors of complete clinical cure were home systolic blood pressure (SBP) <135 mmHg after one month of spironolactone 100 mg daily (odds ratio 13.0 (3.72, 45.24) p<0.001) and KCNJ5 genotype of the APA (odds ratio 10.37 (2.50, 42.99) p=0.001). The latter remained significant in logistic regression on age, gender, ethnicity, and was itself predicted by elevated urine 18-hydroxycortisol:cortisol ratio. Our findings validate 11C-metomidate PET-CT for accurate, non-invasive detection of patients with unilateral PA, and identify patients most likely to benefit from adrenalectomy.

Comparison of Bolus and Continuous Infusion of Adrenocorticotropic Hormone During Adrenal Vein Sampling

BackgroundAdrenocorticotropic hormone (ACTH) is widely used in adrenal vein sampling (AVS) and can be administered as a bolus injection or continuous infusion. The optimal administration method has not been determined. We aimed to compare the effects of ACTH bolus with infusion on cannulation success, lateralization assessment and adverse events (AEs).MethodsRetrospectively collected data from patients with primary aldosteronism who underwent AVS with ACTH at a tertiary hospital in China. Rate of successful cannulation, lateralization index (LI), complete biochemical remission and AEs related to AVS were analyzed.ResultsThe study included 80 patients receiving ACTH bolus and 94 receiving infusions. The rate of successful cannulation was comparable between bolus and infusion groups (75/80, 93.4% vs 88/94, 93.6%). In those with successful cannulation, the bolus group had a higher selectivity index than the infusion group, while LI [6.4(1.8-17.5) vs. 7.6(2.0-27.8), P=0.48] and rate of complete biochemical remission (43/44, 97.7% vs 53/53, 100%, P=0.45) did not significantly differ between the two groups. One in the bolus and one patient in the infusion group had adrenal vein rupture but they recovered with conservative treatment. The bolus group reported more transient AEs such as palpitation (52.9% vs 2.2%) and abdominal discomfort (40.0% vs 2.2%) than the infusion group.ConclusionsDue to their similar effects on cannulation success and lateralization, but a lower rate of transient AEs in the infusion group, the continuous infusion method should be recommended for ACTH stimulation in AVS.

Feasibility of Imaging-Guided Adrenalectomy in Young Patients With Primary Aldosteronism

Many of the patients with primary aldosteronism (PA) are denied curative adrenalectomy because of limited availability or failure of adrenal vein sampling. It has been suggested that adrenal vein sampling can be omitted in young patients with a unilateral adrenal nodule, who show a florid biochemical PA phenotype. As this suggestion was based on a very low quality of evidence, we tested the applicability and accuracy of imaging, performed by computed tomography and/or magnetic resonance, for identification of unilateral PA, as determined by biochemical and/or clinical cure after unilateral adrenalectomy. Among 1625 patients with PA submitted to adrenal vein sampling in a multicenter multiethnic international study, 473 were ≤45 years of age; 231 of them had exhaustive imaging and follow-up data. Fifty-three percentage had a unilateral adrenal nodule, 43% had no nodules, and 4% bilateral nodules. Fifty-six percentage (n=131) received adrenalectomy and 128 were unambiguously diagnosed as unilateral PA. A unilateral adrenal nodule on imaging and hypokalemia were the strongest predictors of unilateral PA at regression analysis. Accordingly, imaging allowed correct identification of the responsible adrenal in 95% of the adrenalectomized patients with a unilateral nodule. The rate raised to 100% in the patients with hypokalemia, who comprised 29% of the total, but fell to 88% in those without hypokalemia. Therefore, a unilateral nodule and hypokalemia could be used to identify unilateral PA in patients ≤45 years of age if adrenal vein sampling is not easily available. However, adrenal vein sampling remains indispensable in 71% of the young patients, who showed no nodules/bilateral nodules at imaging and/or no hypokalemia. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT01234220.

Comparison of Cortisol, Androstenedione and Metanephrines to Assess Selectivity and Lateralization of Adrenal Vein Sampling in Primary Aldosteronism

Success of adrenal vein sampling (AVS) is verified by the selectivity index (SI), i.e., by a step-up of cortisol levels between the adrenal vein and the infrarenal inferior vena cava samples, beyond a given cut-off. We tested the hypothesis that androstenedione, metanephrine, and normetanephrine, which have higher gradients than cortisol, could increase the rate of AVS studies judged to be bilaterally successful and usable for the clinical decision making. We prospectively compared within-patient, head-to-head, the selectivity index of androstenedione (SIA), metanephrine (SIM), and normetanephrine (SINM), and cortisol (SIC) in consecutive hypertensive patients with primary aldosteronism submitted to AVS. Main outcome measures were rate of bilateral success, SI values, and identification of unilateral PA. We recruited 136 patients (55 + 10 years, 35% women). Compared to the SIC, the SIA values were 3.5-fold higher bilaterally, and the SIM values were 7-fold and 4.4-fold higher on the right and the left side, respectively. With the SIA and the SIM the rate of bilaterally successful AVS increased by 14% and 15%, respectively without impairing the identification of unilateral PA. We concluded that androstenedione and metanephrine outperformed cortisol for ascertaining AVS success, thus increasing the AVS studies useable for the clinical decision making.