FRIDAY, June 20 (HealthDay News) -- New research shows that people with chronically high blood pressure in the blood vessels of the lungs and low serum sodium levels have a very high mortality rate.

Low blood sodium -- called hyponatremia, or HN -- is a known indicator of advanced left heart failure, but the new study from the University of Pennsylvania researchers now connects it with right heart failure in patients with pulmonary arterial hypertension (PAH).

MOUNT LAUREL, N.J. (AP) -- The Campbell Soup Co.'s kid-oriented soups, which feature characters such as Dora the Explorer and Batman on the cans, are getting their second sodium reduction in three years, the company announced Monday.

This time, the 12 soups designed for children will have 480 milligrams per serving, which means the company can legally label them as healthy foods for the first time.

"Your kids can enjoy Dora the Explorer even more," said Douglas R. Conant, Campbell's president and chief executive, said in an interview. "They'll be down to heart-healthy levels."

Learn how salt (sodium) affects your health.

Discover the signs that you may be getting too much salt in your diet.