Primary aldosteronism causing hypertension; early treatment improves outcomes

This study examined the effect of treatment on blood pressure and heart tissue changes in patients with primary aldosteronism.

Primary aldosteronism is a disease in which one or both adrenal glands (small glands attached to the top of each kidney) produce too much aldosterone. The two most common causes for primary aldosteronism are an aldosterone producing tumor located in the adrenal gland and adrenal hyperplasyia (a disorder in which the adrenal glands are hyperactive and make too much aldosterone).

Aldosterone is a hormone that helps control the blood pressure by changing the levels of electrolytes such as sodium and potassium in the blood. Too much aldosterone causes the body to retain sodium and to get rid of potassium. This in turn increases the amount of fluid in the body and therefore increases blood pressure.

High blood pressure along with high sodium levels are believed to cause inflammation, hypertrophy  (enlargement of an organ due to an increase in the size of its cells) and fibrosis (scarring) in the heart tissue. These conditions may lead to an increased left ventricular mass (the left ventricle, one of the four chambers of the heart, pumps blood to most body tissues), which predicts cardiovascular events and death.

Whether targeted treatment of primary aldosteronism could provide long-term cure of high blood pressure and regression of hypertrophied or inflamed heart tissue (return to a less diseased state) remains uncertain.

This study enrolled 323 patients. 180 patients suffered from primary aldosteronism and 143 patients had primary hypertension (a form of high blood pressure that has no identifiable cause).From the 180 primary aldosteronism cases 110 patients were treated with adrenalectomy (a surgical removal of one or both adrenal glands usually performed when a tumor is discovered in one of the glands) and the rest (70 patients) received an aldosterone antagonist (a drug that blocks the effect of aldosterone by binding to its receptor).

Before the patients with primary aldosteronism were treated they had higher left ventricular mass index, showed slightly higher systolic (pressure when the heart is contracting) and diastolic (pressure when the heart is relaxing or filling) blood pressure values and had a 7.2-fold higher prevalence of historical or current atrial fibrillation (an arrhythmia of the heart where the atria, or the chambers that receive blood from the body, quiver instead of beat) compared with primary hypertensive patients.

After the patients with primary aldosteronism were treated (surgically or medically) an average follow up of 3 years was conducted.

Following analysis a marked reduction of systolic and diastolic blood pressures was seen at long-term follow-up in both the surgically and the medically treated patients with primary aldosteronism. In the surgically treated patients a 17 mm Hg decrease in systolic and diastolic blood pressure was viewed (to 135/83 mm Hg) while in the medically treated patients an 18 mm Hg decrease was viewed both for systolic and diastolic blood pressures (to 133/83 mm Hg). The final blood pressures values exhibited in the patients with primary aldosteronism didn’t differ significantly from those achieved in patients with primary hypertension who received reinforced drug therapy (139/86 mm Hg). 

Furthermore, in both the surgically and the medically treated patients with primary aldosteronism, but not in the patients with primary hypertension, left ventricular volume and left ventricular mass index decreased.

Finally, there was no difference in atrial fibrillation occurrence between the surgically and the medically treated patients with primary aldosteronism and those that were treated for primary hypertension.

This study concluded that early diagnosis of primary aldosteronism together with targeted surgical and medical treatment induces a long-term reduction in blood pressure and left ventricle mass.

Early diagnosis of primary aldosteronism is crucial in achieving blood pressure control and regression of heart tissue changes. Late diagnosis may result in permanent alterations, hindering treatment attempts.