| Abstrakt: |
Left ventricular wall mass was studied within the framework of the Cooperative Study in The Netherlands for the evaluation of the effects of CBS on left ventricular function. Normal values, previously established in 58 patients, submitted for diagnostic catheterization, were 102.2 ± 30.6 g/m2 {mean ± s.d.). In the whole group of 914 patients with coronary artery disease left ventricular wall mass index was elevated, with a mean value of 119.2 g/m2. Three years later the wall mass index had returned to normal. At present paired data are available in 80 patients. Their pre-operative mean values were 122.3 g/m2, three years postoperative they also show normal values (103.3 ± 25.7 g/m2). The factors contributing to this increase in left ventricular wall mass were assessed with multivariate stepdown linear regression analysis. Apart from ejection fraction and end-diastolic volume, where also a mathematical relation exists, only a weak relation with cardiac size and the number of previous infarcts was found.The number of patients with essential hypertension in this study is too few to warrant conclusions. It is clear, however, that increased left ventricular wall mass can exist in patients with coronary artery disease, who do not have essential hypertension.Finally, one of the myocardial implications of hypertrophy was assessed by measuring the peri-operative myocardial infarction rate during and after bypass surgery. The infarction rate in patients with an increased wall mass was seen to be twice as high as the infarction-rate in patients with normal or only slightly increased wall mass. These data lead to the following conclusions:(1) Left ventricular wall mass is increased in many patients with coronary artery disease even when they do not have essential hypertension.(2) After coronary bypass surgery, regression of an increased left ventricular wall mass index can be expected; normal values are reached within three years after the operation.(3) In this group of 913 patients undergoing surgery for stable angina pectoris, there was a relationship between left ventricular wall mass and both ejection fraction and end-diastolic pressure. Only a weak relationship existed with the cardiothoracic ratio measured from the chest X-ray, (slight) mitral incompetence and the number of previous infarcts.(4) There is clear evidence that increased left ventricular wall mass is a risk factor for peri-operative myocardial infarction. The incidence in patients with an increased wall mass index above 140 g/m2 is twice that in patients with a wall mass index of less than 140 g/m2. [ABSTRACT FROM PUBLISHER] |
