To verify this finding we have designed a double-blinded, placebo-controlled, randomized clinical trial with skeletal muscle strength, -endurance, Na, K-pump content, cardiac systolic, and diastolic function as primary endpoints. Spironolactone is tested against placebo in 40 participants included among our admitted and out-clinic patients. Muscle function-tests, muscle biopsy and trans-thoracic echocardiography is performed before and after 12 weeks of treatment.