Conclusion
Pre-operative assessment of PEP/LVET ratio was as reliable as invasively measured ejection fraction in separating patients with normal ventricular performance from those with abnormal indices.
Our study demonstrates significant impairment of ventricular performance following aorto-coronary bypass procedures. The duration of this dysfunction is between two and five days following operation and is maximal in the first 48 hours. Meaningful interpretation of systolic time interval changes requires measurement of pre-load and after-load. Changes in these variables account for at least some of the increase in PEP/LVET ratio noted in our study. On the basis of a shortened QS2I these patients are thought to exhibit increased adrenergic activity for the entire period of their hospitalization.
Résumé
Le rapport PEP/LVET (Pre-Ejection Period/Left Ventricular Ejection Time) se compare favorablement à la mesure de la fraction ď éjection — une technique invasive — lorsque ľon veut déterminer si un malade présente une fonction ventriculaire normale ou anormale.
Notre étude a mis en évidence une dysfonction ventriculaire gauche significative après chirurgie aorto-coronarienne. Cette dysfonction dure de deux àcinq jours et elle se manifeste àson maximum au cours des premières 48 heures.
Ľinterprétation des changements observés dans la mesure des intervalles systoliques doit être faite à la lumière des modifications de la pré et de la post-charge; leur mesure est donc nécessaire. Les modifications de ces paramètres sont en partie responsables de ľaugmentation du rapport PEP/LVET observé chez nos malades.
Le raccourcissement des intervalles systoliques noté chez nos patients est attribuable à ľaugmentation de ľactivité adrénergique, observée tout au long de ľhospitalisation.
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References
Cohn, P.R.,et al. Ejection fraction and prognosis in cardiac surgery. Am. J. Cardiol.34: 140–141 (1974).
Martin, E.C., Shaver, J.A., Thompson, M.E.,et al. Direct correlation of external systolic time intervals with internal indices of left ventricular function in man. Circulation, SLIV, 419–431 (1971).
Mailhot, J.W., Sandley, H.; &Harrison, D.C. Left ventricular function following coronary bypass surgery. Circulation 44, Suppl. II, 196 (1971).
Rees, G., Bristow, J.D., Kremkau, E.L.,et al. Influence of aorto-coronary bypass surgery on left ventricular performance. New Eng. J. Med.284: 1116 (1971).
Boudoulas, H., Lewis, R.P., &Karayannacos, P.E. Effect of saphenous vein graft surgery upon left ventricular function. Am. J. Cardiol. (Abstract)31: 123 (1973).
Weissler, A.M. Non-invasive cardiology. Grune and Stratton, New York. pp. 301 (1974).
Weissler, A. &Garrard, C. Systolic time intervals in cardiac disease (I) (II). Modern concepts of cardiovascular disease (January 1971).
Lewis, R.P., Boudoulas, H., Forester, W.F.,et al. Shortening of electromechanical systole as a manifestation of excessive adrenergic stimulation in acute myocardial infarction. Circulation46: 856 (1972).
Weissler, A.M., Peeler, R.G., &Roehll, W.H.J, Relationships between left ventricular ejection time, stroke volume, and heart rate in normal individuals and patients with cardiovascular disease. Am. Heart J.62: 367 (1961).
Seabra-Gomes, R., Sutton, R., &Parker, D.J. Left ventricular function after aortic valve replacement. British Heart J.38: 491 (1976).
Garrard, C.L. {jrJr.},Weissler, A.M., &Dodge, H.T. The relationship of alterations in systolic time intervals to ejection fraction in patients with cardiac disease. Circulation42: 455 (1970).
Matlof, H., Hultgren, H.N., Pfeifer, J.F., &Harrison, D.C. Cardiac function assessed by systolic time intervals after aorto-coronary saphenous vein bypass surgery. British Heart J.35: 714 (1973).
Repogle, R., Levy, M., &DeWall, R.A.,et al. Catecholamine and serotonin response to cardiopulmonary bypass. J. Thoracic and Cardiovasc. Surg.44: 638 (1962),
Cooper, T., Jelinek, M., William, V.T.,et al. Biochemical studies of myocardium and blood during extracorporeal circulation in man. Circulation 31-32, Suppl. I, 1–144 (1965),
Quinones, M.A., Gaasch, W.H., &Alexander, J.K. Influence of acute changes in pre-load and after-load, contractile state and heart rate on ejection and isovolumic indices of myocardial contractility in man. Circulation53: 293 (1976).
Prys-Roberts, C, Gersh, B.J., Baker, A.B.,et al. The effects of halothane on the interactions between myocardial contractility, aortic impedance, and left ventricular performance. Brit. J. Anaesth.44: 634 (1972).
Blackburn, J.P., Conway, C.M., Davies, R.M.,et al. Valsalva responses and systolic time intervals during anaesthesia and induced hypotension. Brit. J. Anaesth.45: 472 (1976).
Dauchot, P.J., Rasmussen, J.P., Nicholson, D.H.,et al. On line systolic time intervals during anaesthesia in patients with and without heart disease. Anaesthesiology44: 472 (1976).
Johnson, A.D., O’Rouke, R.A., Karliner, J.,et al. Effect of myocardial revascularization on systolic time intervals in patients with left ventricular dysfunction. Supp. 1 to Circulations, Vols. XLV and XLVI, 1–91 (May 1972).
Boudoulas, H., Lewis, R.P., Vasko, J.S.,et al. Left ventricular function and adrenergic hyperactivity before and after saphenous vein bypass. Circulation53: 5 (1976).
Byrick, R.J.,Kay, J., &Nobel, W.H. Extravascular lung water accumulation following coronary artery surgery. C.A.S.J. (In preparation.)
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Byrick, R.J., Teasdale, S.J. & Young, P. Systolic time interval changes after aorto-coronary bypass. Canad. Anaesth. Soc. J. 24, 175–185 (1977). https://doi.org/10.1007/BF03006230
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DOI: https://doi.org/10.1007/BF03006230