A new indicator of contrast-induced nephropathy in patients undergoing elective coronary angiography: tissue doppler-derived E/(EA × SA) index.

Abstract

Hemodynamic instability plays an important role in the development of contrast-induced nephropathy (CIN), which is an important complication of coronary angiography. Left ventricular (LV) end-diastolic pressure (LVEDP) accurately reflects hemodynamic changes. In clinical practice, measuring LVEDP invasively presents some challenges and is not always accessible. This study aimed to investigate the relationship between tissue Doppler-derived early diastolic conduction velocity (E)/[early mitral annular diastolic velocity (Ea), × peak systolic annular velocity (Sa)] index, an important surrogate for LVEDP, and CIN in patients undergoing elective coronary angiography (ECA). This retrospective study included 388 consecutive patients undergoing ECA. CIN was defined as a 25% or 0.5 mg/dL increase in serum creatinine compared to baseline values within 72 hours after ECA. Mehran score was calculated in all patients and systolic and diastolic functions were evaluated with Doppler echocardiography. The incidence of CIN was 9.7%. There was a positive correlation between LV EDP levels and LV E/(Ea × Sa) index (r = 0.691, p < 0.001). Higher LV E/(Ea × Sa) index (OR = 1.03, p < 0.001) and Mehran score (OR = 1.41, p < 0.001) were independent predictors of CIN. The threshold value of LV E/(Ea × Sa) index in predicting CIN was > 1.71 with 75.7% sensitivity and 84.3% specificity (AUC = 0.825). In patients undergoing ECA, the non-invasively measured E/(Ea × Sa) index can be used as a risk indicator for CIN.