Effects of propranolol on left ventricular wall movement in patients with ischaemic heart disease.

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RESUMO

To assess the acute and chronic effects of propranolol on left ventricular wall motion, simultaneous, echo-, apex-, and phonocardiograms were recorded in 10 normal subjects and in 16 patients with ischaemic heart disease, nine with co-ordinate (group A) and seven with incoordinate (group B) contraction in the control site. Records were made after 0.1 mg/kg intravenous or oral therapeutic dose for one week. In all, propranolol caused small reductions in heart rate and peak VCF. In normal subjects, intravenous and oral propranolol caused rate-related increases in the intervals Q to A2, Q to minimum dimension, and Q to mitral valve opening. The effects were different in patients with ischaemic heart disease. In group A, inward wall movement ceased 80 ms early, and this was not attributable to a change in heart rate. Diastolic events were unaltered. In group B, minimum dimension already occurred early. Propranolol did not alter systolic events further, but increased delay in mitral valve opening, 'O' point, prolonged isovolumic relaxation, reduced peak rate of dimension increase, and aggravated incoordinate relaxation. It is concluded that the effects of propranolol in patients with ischaemic heart disease are modified in a manner that cannot be predicted from observations made in normal subjects. It also appears that complex drug effects can be assessed in man from the measurement of time intervals derived from multiple non-invasive techniques.

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