The Influence of Isolated Stenosis of Left Anterior Descending Artery on Left Ventricular Regional Function in Right Dominate Coronary Artery Patients: Clinical Study with Multi-slice CT Scanning

Objective To explore the influence of isolated stenosis of left anterior descending artery( LAD) on the left ventricular( LV) regional function in right dominate coronary artery patients. Methods During the past two years at authors' hospital,256-slice CT coronary angiography was performed in 1584 patients,among whom isolated stenosis of LAD was detected in 248. The clinical data were retrospectively analyzed. The patients were divided into 4 groups according to the severity of LAD stenosis: stenosis ≤25%( no obvious stenosis,n = 92),mild stenosis( n = 63),moderate stenosis( n =45),and severe stenosis( n =48). LV regional functional parameters,including end-systole wall thickness( ESWT),end-diastole wall thickness( EDWT),wall thickening( WT),wall motion( WM) were calculated automatically.The differences in LV regional function were compared between each other among the four groups,and the correlation between LAD stenosis and LV regional function was evaluated. Results( 1) EDWT: for segments of S1,S3,S14 and S15,statistically significant differences in EDWT existed between the severe stenosis group and no obvious stenosis group( P =0. 001,0. 007,0. 016,0. 002 0. 05),mild stenosis group( P = 0. 004,0. 024,0. 009,0. 002 0. 05). For segments of S2 and S7,severe group was different from no obvious stenosis group( P = 0. 009,0. 000 0. 05),mild stenosis group( P =0. 014,0. 000 0. 05) and moderate stenosis group( P = 0. 021,0. 031 0. 05). For segment of S13,significant difference existed between no obvious stenosis group and mild stenosis group,severe stenosis group( P = 0. 005,0. 009 0. 05) and mild stenosis group( P = 0. 009,0. 018 0. 05),while no obvious difference existed between severe and mild stenosis group( P = 0. 803). Positive correlation existed between the EDWT of S1,S3,S8 and the severity of LAD stenosis( P =0. 034,0. 032,0. 026 0. 05; r = 0. 152,0. 153,0. 159).( 2) WT: for S8,there was significant difference between moderate stenosis group and no obvious stenosis group( P = 0. 005 0. 05),mild stenosis group( P = 0. 006 0. 05) and severe stenosis group( P = 0. 045 0. 05). Significant difference in WT of S15 existed between no obvious stenosis group and mild stenosis group,severe stenosis group( P = 0. 013,0. 012 0. 05) and mild stenosis group( P = 0. 09,0. 008 0. 05),while no difference in WT of S15 was found between severe stenosis group and mild stenosis group( P = 0. 990 0. 05).The WT values of S3,S15 bore a negative relationship with the severity of LAD stenosis( P = 0. 005,0. 015 0. 05; r =-0. 199,- 0. 173).( 3) ESWT and WM: No differences in ESWT and WM existed between each other among the four groups,and no definite correlation with severity of stenosis was found( P 0. 05).( 4) EDWT values of S1,S2,S3,S7,S13,S14 and S15 were increasing from no obvious stenosis group to severe stenosis group,while WT values of S8 and S15 were decreasing with the degree of stenosis severity. Conclusion No obvious or only mild isolated stenosis of left anterior descending artery has no significant influence on left ventricular regional functions. In the presence of moderate to severe stenosis of left anterior descending artery,the LV regional function parameters,especially EDWT and ESWT of S1,S2,S3,S7,S13,S14 and S15,will be affected. Certain correlation exists between the severity of LAD stenosis and some LV regional function parameters.