To the Editor:
We read with great interest the exciting article entitled “Comprehensive First‐Line Magnetic Resonance Imaging in Hypertension: Experience From a Single‐Center Tertiary Referral Clinic.”1
This is the first study on the screening for asymptomatic organ damage and secondary causes of hypertension with first‐line magnetic resonance imaging, but we would like to comment on the findings.
The prevalence of primary aldosteronism in patients with resistant hypertension is approximately 25%.2 The authors identified a rate of 14.5% in their study, which we believe is low for this group if appropriate screening was performed. First, renin measurement alone is not enough to rule out patients with primary aldosteronism. As the authors mentioned, these tumors may be small and therefore the diagnosis may be missed.1, 3 Computed tomography and magnetic resonance imaging lack sensitivity for detecting primary aldosteronism. In these patients, the aldosterone to renin ratio should be routinely measured to rule out aldosteronism.4 Adrenal venous sampling is necessary after confirmation.2 If primary aldosteronism is present in a patient with resistant hypertension, spironolactone is the first drug of choice (not fourth). Primary aldosteronism may cause cardiovascular diseases and stroke, independent of the effects of hypertension.2 Some patients may also benefit from surgery, although the opportunity may be lost in these patients. In addition, serum K levels should be measured in these patients. First, why did the authors give spironolactone to only one patient? Second, did the patient who died of a stroke also have aldosteronoma? In renal stenosis, it is also recommended to screen for primary hyperaldosteronism. So, first‐line magnetic resonance imaging is not enough for secondary hypertension screening.
It is common to miss primary aldosteronism in daily practice. In addition, the three drugs used in resistant hypertension may affect aldosterone and renin levels.
In addition, screening for Cushing disease should have been performed for all 12 cases with adrenal abnormalities, and aldosterone and renin measurements should be performed in all patients even when findings from adrenal imaging are normal. It also would have been useful to have the potassium levels for all patients.
For this study, I am not sure if there is extra benefit of the first‐line magnetic resonance imaging in addition to routine secondary hypertension screening.
Conflict of Interest
The author reports no conflicts of interest.
References
- 1. Burchell AE, Rodrigues JC, Charalambos M, et al. Comprehensive first‐line magnetic resonance imaging in hypertension: experience from a single‐center tertiary referral clinic. J Clin Hypertens (Greenwich). 2017;19:13‐22. [DOI] [PMC free article] [PubMed] [Google Scholar]
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