The relationship between the atrial systole-ventricular systole interval and left ventricular function

Pressure-flow studies in man: effect of atrial systole on left ventricular function.

In order to evaluate the effects of atrial contraction on left ventricular function, the pressure gradient technique was used to measure instantaneous aortic blood flow and pressure in nine patients, six having complete heart block and three having normal sinus rhythm. From these data both left ventricular stroke volume and stroke work were calculated. Ventricular rate was controlled by transve...

Duration of the phases of left ventricular systole.

• The influence of heniodynamic variables on the duration of certain phases of ventricular systole has been studied by several investigators in intact animals and in isolated heart preparations.' Even in isolated hearts, it is not possible to change one heniodynainic variable without inducing changes in one or more intrinsic determinants of the heart's performance. For example, augmenting strok...

The duration of left ventricular systole in mitral incompetence.

In mitral incompetence the left ventricle has two exits and it has been suggested that diminished resistance to emptying causes left ventricular systole to be shorter than normal (Brigden and Leatham, 1953). Theoretically the elevation of left ventricular end-diastolic pressure that is found in severe mitral incompetence (Ross et al., 1958; Nixon, 1961a) should result in prolongation of systole...

Observations on the Change of Ventricular Systole

In a previous communication (1) we have briefly described the electrocardiographic changes of the QT interval during exercise in normal subjects. On the average the corrected QT interval or K was 7% greater than that observed during rest, and with the onset of recovery it diminished by 9%o within the first two minutes and gradually returned to the original value at rest. There was no significan...

Influence of Atrial Systole on Effective Ventricular Stroke Volume.