title: The effect of atrial pacing on the mitral echocardiogram of mitral stenosis recorded simultaneously with haemodynamic data.
abstract: Simultaneous mitral echocardiograms and haemodynamic data were recorded in six cases of mitral stenosis during atrial pacing. Due to the prolongation of the P-R interval during atrial pacing, the diastolic closure rate E-F was measurable up to a heart rate of 80 per min. only. At a heart rate of 80 or less, both in sinus rhythm and during atrial pacing the diastolic closure rate remained essentially the same in each case. However, above 80/min E-F became too short and post-atrial systolic closure A-B only was available for measurement which was higher in each case than its corresponding E-F value. This contrasts with cases with sinus rhythm where the diastolic closure rate E-F measurable up to a heart rate of 110 per minute.
mesh_terms: D002302:Cardiac Output; D004452:Echocardiography; D006339:Heart Rate; D006439:Hemodynamics; D006801:Humans; D008946:Mitral Valve Stenosis / Q000175:diagnosis / Q000503:physiopathology* / Q000628:therapy; D010138:Pacemaker, Artificial