DETERMINANTS OF SEVERITY OF LEFT-VENTRICULAR DYSFUNCTION IN AUSTRALIAN MEN AND WOMEN WITH CORONARY-DISEASE AGED 65 YEARS OR LESS

Background: The degree of left ventricular (LV) impairment is an impor tant determinant of long term outcome in patients with coronary artery disease (CAD). Aim: We aimed to determine variables predictive of the severity of LV dysfunction in men and women aged 65 years or less wit h CAD, and to quantitate their contributions. Methods: We documented a therogenic variables and extent of LV impairment and CAD severity at a ngiography in 521 consecutively studied men and women aged 65 years or less (381 males and 140 females). We assessed severity from an LV imp airment score (Green Lane) and the ejection fraction. We related sever ity to quantitative and categorical variables which included the sever ity of angina (no angina, stable and unstable angina). Results: The LV impairment score correlated closely (negatively) with the ejection fr action (r = -0.783, p = 0.0001). There were eight variables independen tly predictive of the severity of LV impairment assessed by the LV sco re. The variables in descending order of relative importance in predic ting the LV scores were past history of myocardial infarction (MI), nu mber of significantly diseased vessels(>50% luminal obstruction), life -time smoking dose, log-triglycerides, total cholesterol to HDL-C rati o, hypertension, age and Body Mass Index (BMI). They were all positive relationships. Together they correctly classified the LV scores of 52 .6% of the patients. Gender was not an independent contributor to the LV score when other variables were controlled. When the contributions to the variance in LV scores of past history of MI(15.4%) and number o f significantly diseased vessels (2.6%) were controlled, life-time smo king dose independently explained 2.1% (p < 0.01) of the variance. The LV impairment score was 55% higher in heavy smokers than in non-smoke rs (p = 0.01). When we compared patients with stable and unstable angi na, LV scores are higher and ejection fraction lower in the unstable a ngina patients consistent with them having a greater degree of LV dysf unction. Conclusion: We conclude that variables other than a history o f MI and CAD severity contribute significantly to the variance of the degree in LV impairment in CAD patients among which the life-time smok ing dose, triglycerides, TC/HDL-C, hypertension and increased BMI are all relevant to prevention, and that patients with unstable vs stable angina usually have more impaired LV function.