Association of left ventricular size with cardiovascular risk factors and coronary artery calcium score in the general population: The Heinz Nixdorf Recall study

Abstract

Purpose: Left ventricular (LV) size is associated with cardiovascular mortality and morbidity. On cardiac CT images, information on LV size is readily available. We aimed to determine the association of CT-derived LV area with cardiovascular risk factors and coronary artery calcification (CAC) in the general population. Methods: LV area was quantified from non-contrast enhanced CT in axial, end-diastolic images at a mid-ventricular slice in participants of the population-based Heinz Nixdorf Recall Study, free of cardiovascular disease. Regression analysis was used to determine the association of LV size with risk factors and CAC in crude and adjusted analysis. Log-transformation was used to normalize the CAC distribution. Results: Overall, 3926 subjects (age 59.2±7.7years, 53% female) were included. Men had larger LV size than women (4551±678 vs. 3744±535 mm2, p<0.0001). There was a trend towards lower LV size in older subjects (men: 4598±656 vs. 4463±689 mm2; women: 3747±533 vs. 3727±548 mm2, for 45-55 and 66-75 years, respectively). Body mass index (BMI) was a major predictor of LV size (Estimate (95%Confidential Interval): men: 57.0 (49.1-64.8) mm2/kg/m2; women: 51.0 (46.9-55.2), both p<0.0001). Also, systolic blood pressure (men: 57.8 (41.2-74.5) mm2 /10mmHg; women: 58.9 (47.9-69.9)) and intake of antihypertensive medication (men: 186.7 (117.7-255.6) mm2; women: 238.7 (189.5-287.9), all p<0.0001) were correlated with LV size. HDL was negatively associated with LV size (men: -19.3 (-30.5–8.1) mm2/5mg/dl; women: -23.7 (-30.7–16.6), p<0.0001). Total cholesterol showed a negative link (men: -12.5 (-20.9–4.1)mm2/10mg/dl, p=0.003), however not reaching statistical significance in women: -4.1 (-10.1-1.9), p=0.18. Male but not female active smokers had lower LV size (men: -88.6 (-162.2—15.0) mm2, p=0.018; women: -0.4 (-57.6-56.9), p=0.99). In gender specific multivariable analysis age, BMI, systolic blood pressure, antihypertensive medication, and cholesterol levels remained independent predictors of LV size. CAC-Score was associated with LV size in unadjusted (men: 19.7 (7.3-32.9)% percent increase in CAC+1/standard deviation of LV area; women: 33.9 (22.2-46.7)%, both p<0.0001) and risk factor adjusted models (men: 16.5 (4.8-29.4)%, p=0.005); women: (12.8 (2.5-24.2)%, p=0.014). Conclusion: Gender, BMI, and hypertension are major predictors of LV size as determined by non-contrast cardiac CT. LV size is associated with CAC-Score independent of traditional risk factors. Further research is needed to determine if LV size measures enhance the value of this imaging technology for cardiovascular events prediction.