Endocrine Abstracts

Background: Primary aldosteronism (PA) patients have increased left ventricular mass (LVM) and increased cardiovascular morbidity compared with those with essential hypertension. Echocardiographic studies have demonstrated that adrenalectomy or spironolactone decreases LVM. The aim of the present study was to use MRI to assess both LVM and cardiac function before and during stress testing, at baseline and after treatment with adrenalectomy or spironolactone, compared with healthy subjects (HS).

Material and methods: Fifteen recently diagnosed PA patients and 24 age- and sex-matched HS performed a baseline cardiac MRI with a 3.0 Tesla scanner. Imaging was performed at rest and during stress-testing with adenosine 140 μg/kg per min. Short-axis images were used for quantifications of LVM and left ventricular volumes. A follow-up MRI was performed in 20 of the HS and 14 of the PA patients, at least one year after starting specific treatment.

Results: Nine patients (60%) had unilateral PA, the remaining bilateral (n=5, 33%) or not representative (n=1, 7%) adrenal vein sampling. The PA and HS did not differ in age or sex. PA patients had higher baseline blood pressure (BP) than the HS (median BP 138/90 vs 118/75, P<0.001). At follow-up, 8/14 PA were adrenalectomized (median 18 months). The remaining 6/14 were on spironolactone (median 21 months). LVM at baseline differed significantly between the PA and HS groups (median 145 vs 97 g; P<0.001). At follow-up, the PA group had a significant reduction in LVM (median -18 g, P<0.001), but no difference in cardiac output (CO) response to stress compared with baseline (follow-up PA median stress CO/rest CO 1.4 vs baseline 1.5, P=ns).

Conclusion: Cardiac MRI showed rapid reduction in LVM in PA after treatment with adrenalectomy or spironolactone. CO response to stress remained unchanged after treatment. Our results underline the importance of early diagnosis and treatment of PA.