Adrenalectomy for primary aldosteronism: long-term follow-up study in 29 patients

Unadjusted Plasma Renin Activity as a "First-Look" Test to Decide Upon Further Investigations for Primary Aldosteronism

The authors sought to define the 95th percentile of plasma renin activity (PRA) in a sample of patients with confirmed primary aldosteronism (PA) prior to adjustment of medications as a practical "first-look" test to identify those with very low ultimate likelihood of having PA. The aldosterone to renin ratio (ARR) was measured without adjustment of antihypertensive medications, with further workup as appropriate. Two groups were defined: patients with surgically "confirmed PA" (n=58) and patients with "high-probability PA" (n=59), defined as having any of the following: computed tomography-confirmed adrenal adenoma plus lateralizing adrenal vein sampling (AVS) without surgery, high ARR and hypokalemia but nonlateralizing AVS, or ARR more than four times the upper limit of normal. The PRA 95th percentile was 1.0 ng/mL/h. All outliers had hypokalemia and two had adrenal adenomas. There was no difference between the confirmed and high probability groups. In the absence of highly suspicious clinical features, patients with unadjusted PRA >1.0 ng/mL/h do not warrant further investigation for PA.

Treatment of primary aldosteronism: Where are we now?

Primary aldosteronism (PA) is an important cause of secondary hypertension, is being increasingly diagnosed and may account for more than 10% of hypertensive patients, both in primary care and in referral centers. Aldosterone excess is associated with adverse cardiovascular, renal and metabolic effects that are in part hypertension-independent. Laparoscopic adrenalectomy remains the mainstay of treatment for unilateral forms of PA, whereas medical treatment is recommended for bilateral forms of PA. However, a favourable surgical outcome depends on several factors and many patients are not suitable for this treatment. On the other hand, surgery in patients considered to have bilateral PA may contribute to better blood pressure control. In this review, established and novel strategies for the management of different types of PA are discussed.

Long-term results of laparoscopic adrenalectomy for primary aldosteronism

BACKGROUND

The management of primary aldosteronism is currently achieved by both medical and surgical treatment. Laparoscopy has in recent years unquestionably become the gold standard in adrenal surgery for benign lesions. This study aims to evaluate our clinical results among patients who underwent laparoscopic adrenalectomy (LA) for primary aldosteronism.

METHODS

From January 1994 to January 2006, amid LA series, 59 primary aldosteronism patients were treated in our institution. Patients were 33 males and 26 females with mean age 49.3 yr (19-78). The mean body mass index was 25.9 kg/m2 (20.5-33.3). The mean size of lesion was 2.9 cm (1-5.5). Clinical symptoms were as follows: hypertension and symptomatic/asymptomatic hypokalemia (54), hypokalemia (5).

RESULTS

Thirty-five left and 24 right LA were performed. On the left side, 22 procedures were carried out by anterior approach, 9 by anterior submesocolic route, and 4 by means of flank approach. All right procedures were completed by the anterior supine approach. The mean operative time was 103.5 min for left and 92.8 min for right adrenalectomy. There was one major complication, a colonic post-operative fistula, regarding a left adrenalectomy case. The mean post-operative hospital stay was 3 days (1-9). The cure rate of hypertension and hypokalemia was similar to the current literature results.

CONCLUSIONS

LA is a safe and effective option in the treatment of primary aldosteronism. Appropriate selection of patients, larger adrenal masses and duration of symptoms are determining factors in the success rate of hypertension management.

Rare normalization of blood pressure after unilateral adrenalectomy in 31 patients with Conn syndrome

BACKGROUND

Adrenal tumor excision in patients with Conn syndrome is not always followed by normalization of blood pressure (BP). The aim of the study was to determine predictors of persistent hypertension during long-term observation after adrenalectomy.

MATERIALS AND METHODS

Thirty-one patients (23 F and 8 M) with Conn syndrome and adrenal tumor subjected to unilateral adrenalectomy were included. The duration of hypertension ranged from 1 to 30 years and observation time from 1 to 10 years.

RESULTS

Beneficial impact of adrenalectomy on BP control was found in 25 patients, including only 10 patients with BP normalization. Patients with normalization of BP were significantly younger [41 (36-46) vs 53 (48-57) years; p = 0.002] and had lower pulse BP [72 (56-89) vs 93(80-106) mmHg; p = 0.03]. Significant decline of maximal values of systolic and diastolic BP after surgery was observed [59 (47-72) and 29 (20-37) mmHg, respectively]. The analysis revealed that age over 50 years and pulse BP over 70 mmHg predict the persistence of hypertension after surgery.

CONCLUSION

Normalization of BP after adrenalectomy is observed only in 32% of patients with Conn syndrome regardless the normalization of hypokalemia. BP normalization in long period observation was more frequently found in younger patients with lower pulse BP.

Long-Term Results of Adrenalectomy in Patients with Aldosterone-Producing Adenomas: Multivariate Analysis of Factors Affecting Unresolved Hypertension and Review of the Literature

The long-term surgical cure rate of patients with primary aldosteronism varies widely, and causes of persistent hypertension are not completely established. We reviewed retrospectively charts from 98 patients (range, 19–70 years old) with aldosterone-producing adenomas who underwent unilateral adrenalectomy. At a median follow-up of 81 months (range, 18–186 months), the mean blood pressure values improved in 95 out of 98 (96.9%) patients, although hypertension was cured only in 71 out of 98 (72.4%) patients. Multivariate analysis using a logistic regression model adjusted for duration of follow-up showed that only age of the patients and duration of the disease independently correlated with unresolved hypertension. The cumulative odds ratio (OR), obtained using the logistic regression function, was 5.38 (95% CI 1.78–16.22), and the OR of single variables were 1.32 (95% CI 0.36–19.83) and 4.56 (95% CI 1.41–14.78), respectively. By using discriminant analysis to derive a classification function for the prediction of unresolved hypertension, a maximum predictive power of 75 per cent was achieved. In conclusion, in patients with an aldosterone-producing adenoma undergoing surgery, the combination of age and duration of hypertension gave the best predictive power of a linear classification function and represented the main independent risk factors affecting hypertension cure rate.

Long-term follow-up after adrenalectomy for primary aldosteronism

The objective of this study was to assess the long-term effects of adrenalectomy on the blood pressure and antihypertensive medication in patients with primary aldosteronism (PA). Twenty-four patients (15 female and 9 male) with a mean age of 48.3 +/- 10.8 years underwent surgery for PA in our institution between 1988 and 2001. All subjects were re-examined with a complete clinical work-up after a mean follow-up period of 86 +/- 48 months, including blood pressure readings (<140/90 mmHg defined as normal), endocrine adrenal function, and specific medication. All patients suffered from hypertension (onset 8.5 +/- 5.5 years prior to surgery). In 92% of the patients, hypokalemia was present (onset 2.0 +/- 2.6 years prior to surgery). The histopathologic examinations revealed unilateral adenomas in 23 patients and a bilateral hyperplasia in one patient. At follow-up, 33% (8) of the patients were completely cured (normal blood pressure and no antihypertensive treatment), with seven of these eight patients being under 50 years of age at the time of surgery. One patient revealed a contralateral aldosterone-secreting adrenal adenoma during the subsequent endocrine and imaging examination 44 months after the first operation. Despite normalized plasma-aldosterone concentration (PAC), plasma-renin-activity (PRA) and serum potassium levels, a long-lasting insufficiently treated hypertension due to the delayed diagnosis in patients with PA may explain the persistent blood pressure elevation, indicating the necessity of a life-long, regular control of the blood pressure and antihypertensive medication.

Non-invasive adrenal imaging in primary aldosteronism. Sensitivity and positive predictive value of radiocholesterol scintigraphy, CT scan and MRI

The aim of this study was to evaluate the sensitivity and positive predictive value (PPV) of dexamethasone-suppression norcholesterol scintigraphy (NCS), computed tomography (CT) scanning and magnetic resonance imaging (MRI) in patients with primary aldosteronism (PA) who had undergone unilateral adrenalectomy. A series of 49 patients with confirmed PA was reviewed. There were 18 (36.7%) men and 31 (63.3%) women, with a median age of 47 years (range, 23-66 years). NCS was performed in all patients, and 46 (93.9%) and 31 (63.2%) underwent CT scan and MRI, respectively. Final pathology showed an aldosterone-producing adenoma in 45 (91.8%) patients, unilateral nodular cortical hyperplasia (NCH) in two (4.1%) and unilateral microscopic cortical hyperplasia (MCH) in two (4.1%). No aldosterone-producing carcinoma or bilateral adenomas were found. The greatest diameter of the removed adrenal tumour was in the range 8-40 mm (median, 14 mm). The PPV of adrenal imaging was 97.6% for NCS, 85.0% for CT scan (P=0.04) and 83.3% for MRI (P=0.03), and the sensitivity was 85.4%, 85.0% and 74.1%, respectively (P=NS). The age and the main biochemical parameters did not differ significantly (P=NS) between patients with true positive and false negative results of the imaging procedures. NCS accurately depicted all patients with NCH and MCH, whilst CT scan and MRI failed to diagnose such unilateral adrenal gland hyperfunction in two and three patients, respectively. The overall sensitivity of combined NCS and CT scan was 100%. In conclusion, in patients with PA, both NCS and CT scan are necessary to confirm the exclusive unilateral adrenal hyperfunction and, subsequently, to establish the appropriate treatment.

Discriminating factors for recurrent hypertension in patients with primary aldosteronism after adrenalectomy

Patients with primary aldosteronism show relatively high rates of hypertension after adrenalectomy, but the risk factors for postoperative hypertension remain unclear. Forty-six patients with primary aldosteronism (PA) who had undergone adrenalectomy between 1976 and 1998 were enrolled in this study. Follow-up information including blood pressure (BP) and cardiovascular complications was collected by means of correspondence or telephone contact. At discharge BP was normalized in 34 patients (72%); hypertension persisted in the remaining 12 patients, but BP control was significantly improved. The patients who remained hypertensive at discharge had longer durations of hypertension than did those with normalized BP. After an average follow-up period of 12.2 years, 16 of 34 BP-normalized patients (47%) had recurrent hypertension. Age at adrenalectomy, preoperative serum creatinine level and systolic blood pressure at discharge were significantly higher in patients with recurrent hypertension than in those without it. A multivariate logistic regression analysis revealed that only the level of serum creatinine was independently associated with the incidence of recurrent hypertension. Patients with serum creatinine of 0.9 mg/dl or greater had significantly higher rates of recurrent hypertension than those with lower values of serum creatinine. Cardiovascular complications occurred in 5 patients prior to the surgery and in 2 patients during the follow-up period. Although the severity of renal involvement is subclinical, renal damage may play an important role in the development of hypertension during a long period after adrenalectomy in patients with PA.

Cause of residual hypertension after adrenalectomy in patients with primary aldosteronism

The cause of residual hypertension after adrenalectomy for primary aldosteronism (PA) is unknown. The purpose of this study is to investigate the characteristic pathological kidney features associated with PA. Between 1977 and 1999 at our hospital, 26 patients with PA caused by a unilateral adrenal cortical adenoma (Conn's syndrome) underwent unilateral adrenalectomy with concurrent open-wedge renal biopsy. Patients were categorized into two groups: (1) those with normotension with diastolic blood pressure less than 90 mm Hg who were not administered antihypertensive drugs, and (2) those with residual hypertension with diastolic blood pressure of 90 mm Hg or greater who were administered medication for 6 months after surgery. Thirteen patients were cured of hypertension postoperatively, and 12 patients were administered antihypertensive medications. Glomerulosclerosis, renal arteriolosclerosis, and preoperative left ventricular mass (LVM) index were worse in the group with residual hypertension than in that with normotension (17.8% +/- 7.8% versus 9.6% +/- 3.8%; P = 0.01; 2.5 +/- 0.5 versus 1.6 +/- 0.4, Bader's grade; P = 0.005; and 165 +/- 31 versus 139 +/- 24 g/m(2); P = 0.02, respectively). Severity of tubulointerstitial injury, preoperative duration of hypertension, preoperative severity of proteinuria, plasma aldosterone level, and serum potassium concentration were not significantly different between the two groups. In conclusion, severity of glomerulosclerosis and arteriolosclerosis and LVM are related to blood pressure after adrenalectomy in patients with PA.

The Clinicopathologic Significance of Unilateral Adrenal Cortical Hyperplasia: Report of an Unusual Case and a Review of the Literature

We report a case of unilateral primary adrenal cortical hyperplasia associated with hyperaldosteromsm in a 39-yr-old Chinese man. The patient presented with hypertension hy pokalemia, primary hyperaldosteronism(1) suppressed renin activity, and was complicated with aortic dissection. The aortic dissection required emergency realignment while unilateral laparoscopic adrenalectomy was performed subsequently Pathologic examination of the adrenal lesion revealed multiple cortical nodules (up to 1 4 cm in diameter). No telomerase activity was detected in the adrenal lesion. A review of the literature showed that unilateral adrenal cortical hyperplasia has a predilection for the left side occurring more often in males. We conclude that unilateral adrenal cortical hyperplasia is a rare but unique entity and that unilateral adrenalectomy is the treatment of choice.

Essential hypertension: first reason for persistent hypertension after unilateral adrenalectomy for primary aldosteronism?

BACKGROUND

Despite cure of primary aldosteronism by surgical resection, hypertension persists postoperatively in 30% to 50% of patients. The aim of this study was to determine factors influencing long-term outcome of blood pressure after unilateral adrenalectomy for primary aldosteronism.

METHODS

Records of 100 patients who underwent unilateral adrenalectomy for primary aldosteronism from 1970 through 1997 were reviewed. Patients were distributed in 2 groups according to whether blood pressure was normal (criteria of World Health Organization). Clinical, biochemical, and pathologic data were compared.

RESULTS

All patients were biochemically cured. Blood pressure was normal in 56 patients and improved in 44 (mean follow-up, 69 and 59 months). Persistent hypertension correlated with age, known duration and seriousness of preoperative hypertension, family history of hypertension, no preoperative response to spironolactone, and contralateral adrenal hypertrophy. Gender, surgical approach, and pathologic findings were not predictive factors of blood pressure outcome. The prevalence of hypertension was almost the same in these postoperative patients as the prevalence of essential hypertension in a random population of the same age.

CONCLUSIONS

Early unilateral adrenalectomy allows cure or improvement of hypertension in all patients with primary aldosteronism induced by unilateral excessive source of aldosterone secretion regardless of the pathologic findings. Persistent hypertension suggests that coexisting essential hypertension is present.