New CT Scan Can Diagnose Most Common Cause of High Blood Pressure

A new way to diagnose primary aldosteronism (PA), probably the single-most common cause of hypertension, is on the horizon. PA is difficult to diagnose, and knowing which patients are most likely to benefit from surgery is challenging. 47% of Americans have hypertension, a risk factor for both heart attacks and strokes, contributing to the deaths of more than 670,000 adults annually.

PA is a secondary form of hypertension that causes more end-organ damage and is associated with excess cardiovascular morbidity, including non-fatal myocardial infarction, atrial fibrillation, heart failure, and stroke. PA is underdiagnosed; a recent study estimates that only 1 in every 550 is diagnosed and treated — leaving extremely high numbers at risk for a cardiovascular event. High blood costs in the U.S. are close to $200 billion annually.

New research from the United Kingdom, led by co-senior author Morris Brown, MD, a Queen Mary University of London professor, indicates that PET-CT scans utilizing a short-acting dose of metomidate reliably identify patients with PA. Combined with a simple urinalysis, this new scan helps determine which patients are the most likely to benefit from surgery. Brown adds, “These aldosterone-producing nodules are very small and easily overlooked on a regular CT scan.

“When they glow for a few minutes after our injection, they are revealed as the obvious cause of hypertension, which can often be cured. Until now, 99% are never diagnosed because of the difficulty and unavailability of tests.”

Brown and his team studied the records of 128 patients who had these scans. 61% had surgery, with the remainder having medication therapy. The new PET-CT scan utilizing metomidate was as effective as the previous invasive catheter test. The team adds that the new test combined with a simple urinalysis helps determine which patients are most likely to experience successful surgery results resulting in the discontinuation of blood pressure medications.

The UK’s Minister of State for Health, Will Quince, explained, “This technological breakthrough, made possible through government-backed funding, can save lives by identifying nodules on the bladder which cause high blood pressure so they can be removed.”