Z032

 

A Surgical Treatment for Cardiomyopathy

 

A Graf 1, M Gurnell 2, TT Chung 1, 1 Department of Endocrinology and Diabetes, University College Hospital London NHS Foundation Trust, 2 Department of Endocrinology and Diabetes, Cambridge University Hospitals NHS Foundation Trust

 

 

We present a case of refractory hypertension and severe cardiomyopathy, which highlights the importance of considering the differential diagnosis of primary aldosteronism.

 

The case: A 57-year-old male was referred to the local cardiology unit with heart failure. He had an elevated blood pressure (180/90), despite treatment with multiple anti-hypertensives. An echocardiogram demonstrated severe concentric left ventricular hypertrophy (LVH).

 

Over the next five years, he became almost house bound as his hypertension and heart failure worsened and eventually required a pericardial window for significant effusion. He was extensively investigated by the cardiologist (including endomyocardial biopsy and genetic testing) but no cause for cardiomyopathy was found. A FDG-PET scan did show an incidental finding of a 2cm right adrenal nodule.

 

A referral to our endocrinology department was made, an elevated aldosterone renin ratio (ARR) of >25,123 (normal range <1200) was found. Years prior an elevated ARR had been identified at a peripheral hospital but as no adrenal pathology had been seen on imaging, this finding was not identified as a priority in the investigation of worsening cardiomyopathy at that time.

 

A repeat CT adrenal showed bilateral adrenal nodules (3cm on the right, 2cm on the left, Hounsfield units 20). Adrenal vein sampling was not possible as his interfering medications could not be weaned safely without cardiac decompensation. Instead 11-C Metomidate scanning demonstrated bilateral uptake but with an obvious dominant hot nodule on the right. A right laparoscopic adrenalectomy was performed.

The surgery had a successful outcome. His symptoms markedly improved three months postoperatively and his aldosterone and renin also normalised. Three years later, he remains normotensive (on amiloride and amlodipine only), with unlimited exercise tolerance. His echocardiography showed significant LVH regression.

 

Discussion and key learnings:

    Primary aldosteronism is under recognised, now described as >5% of HT patients and up to 20% in patients with resistant HT.1-3

    Clinicians should particularly consider screening those who meet the criteria suggested by the endocrine society guidelines.1

    Given hypertension can be cured/improved with treatment, a timely and accurate diagnosis is imperative.

    The novel PET/CT scan using the 11C-metomidate molecular tracer that binds adrenal steroidogenic enzymes can be used as an adjunct and/or alternative lateralisation modality.4

 

 

References:

 

1. Funder JW, Carey RM, Mantero F, Murad MH, Reincke M, Shibata H, et al. The Management of Primary Aldosteronism: Case Detection, Diagnosis, and Treatment: An Endocrine Society Clinical Practice Guideline. J Clin Endocrinol Metab. 2016;101(5):1889-916.

 

2. Rossi GP, Bernini G, Caliumi C, Desideri G, Fabris B, Ferri C, et al. A prospective study of the prevalence of primary aldosteronism in 1,125 hypertensive patients. J Am Coll Cardiol. 2006;48(11):2293-300.

 

3. Mulatero P, Stowasser M, Loh KC, Fardella CE, Gordon RD, Mosso L, et al. Increased diagnosis of primary aldosteronism, including surgically correctable forms, in centers from five continents. J Clin Endocrinol Metab. 2004;89(3):1045-50.

 

4. O'Shea PM, O'Donoghue D, Bashari W, Senanayake R, Joyce MB, Powlson AS, et al. (11) C-Metomidate PET/CT is a useful adjunct for lateralization of primary aldosteronism in routine clinical practice. Clin Endocrinol (Oxf). 2019;90(5):670-9.