Contrasting effects of single doses of pindolol and xamoterol on left ventricular diastolic function.

Impaired left ventricular diastolic dysfunction is common in patients with ischaemic heart failure. The beta 1-adrenoceptor partial agonist xamoterol was compared with pindolol, a beta-adrenoceptor blocker with intrinsic sympathomimetic activity, in a haemodynamic study in 17 patients with ischaemic heart disease. Pindolol caused left ventricular end-diastolic pressure, wall stress and T1 to rise, whereas xamoterol produced improvements in all three parameters. These results suggest that xamoterol may be of greater benefit to patients in heart failure.