Assessment of electrocardiographic left ventricular hypertrophy with coronary computed tomographic angiography

Abstract

Background/Aims: The prognostic significance of left ventricular hypertrophy (LVH) in electrocardiogram (ECG) has been widely proven. But there are several problems in ECG diagnosis of LVH. The main concern is the low sensitivity of the ECG-LVH criteria and there is too much portion of false positive. Thus, we hypothesize that other measures such as left ventricular (LV) geometry in coronary computed tomographic angiography (CTA) may reveal some anatomical factors (other than LV mass) which correlate with ECG-LVH. The purpose of this study is 1) to compare measures of coronary CTA in ECG-LVH patients with normal ECG control group and 2) to assess the value of measures other than coronary artery in coronary CTA. Method: Among the 4300 patients who undertaken coronary CTA between March 2003 and April 2009, in the Severance Hospital, Yonsei University College of Medicine, we sorted out 154 patients who met definite criteria for electrical LVH. Additional sorting out was performed for matched control group with normal ECG. LV mass, LV volume, papillary muscle volume and septal distance at 65% RR interval was measured by manual tracing. Result: LV mass and LV volume at 65% RR interval were significantly larger in ECG LVH group (LV mass, 162.7 ± 38.6 in ECG LVH group vs. 139.2 ± 28.7 in normal ECG group, p <0.001; LV volume, 114.1 ± 30.8 in ECG LVH group vs. 105.0 ± 27.7 in normal ECG group, p = 0.011). Papillary muscle mass was significantly larger in ECG LVH group, but when corrected by LV mass, there was no significant difference between ECG LVH group and normal ECG group ( PM mass, 9.0 ± 3.4 vs 7.6 ± 2.7, p < 0.001; PM mass/total LV mass (%), 5.2 ± 1.4 vs. 5.1 ± 1.3, p= 0.734). Mean number of papillary muscle was higher in ECG LVH group, but this finding might be attributable to overall hypertrophic change of myocardium in LVH group (Mean number of papillary

muscles : 2.33 ± 0.53 in ECG LVH vs. 2.17 ± 0.44 in normal ECG, p = 0.013)Conclusion: Left ventricular hypertrophy in ECG might reflect hypertrophy of left ventricle. But solitary papillary muscle hypertrophy does not seem attributable to ECG LVH. Images of coronary CTA at 65% RR interval look reliable for evaluation of LV mass and papillary muscle mass comparing to end-diastolic CT images.