Hypokalaemic periodic paralysis and cardiomyopathy.

The results are reported of cardiological examinations, including echocardiography, in nine members of a family suffering from hypokalaemic periodic paralysis, associated with permanent muscular weakness. The studies were performed in periods between attacks of paralysis. The slowly progressive permanent muscular weakness which is found in most of the patients with hypokalaemic periodic paralysis resembles a limb-girdle type dystrophy. Involvement of cardiac muscle is not uncommon in patients with limb-girdle dystrophy. Using a combination of echocardiography and ECG examination, nowadays the most sensitive screening method for the detection of cardiomyopathy, no evidence was obtained for cardiac involvement in hypokalaemic periodic paralysis patients with permanent muscular weakness.