Changes of plasma ionic concentrations may lead to modifications of atrial electrophysiology that can favour AF onset, namely a decrease of atrial CV and a decrease of atrial ERP.

The usefulness of beta blockers in the treatment of congestive heart failure has been questioned. We selected 11 patients, mean age 47.1 +/- 13.8, affected by dilated cardiomyopathy in NYHA class III, who had been taking digoxin and diuretics for a long time. Atenolol 50 mg was added to conventional therapy. Both before and 3 months after treatment a clinical evaluation, chest x-ray, an exercise test, and an echocardiogram were performed. We observed an improvement of NYHA class in five patients. However, the exercise test showed no improvement: 2310 +/- 1299 vs. 2902 +/- 983 total kgm (ns). The echocardiogram showed improvements of the end-systolic diameter (from 6.3 +/- 1 cm to 5.9 +/- 0.8 cm; p less than 0.02), the fractional shortening (from 13.6 +/- 6.3% to 15.2 +/- 5.6%; p less than 0.05) the radius/thickness ratio (from 4.14 +/- 0.5 to 3.5 +/- 0.5; p less than 0.05), and the wall stress (from 208.4 +/- 49 g/cm2 to 163.5 +/- 41 g/cm2; p less than 0.02). The inotropic state index did not show any changes. We conclude that in some patients with dilated cardiomyopathy beta blockers may improve the clinical status and left ventricular performance.

No abstract

No abstract