Tei-Index in coronary artery disease – validation in patients with overall cardiac and isolated diastolic dysfunction

Background The index „isovolumic contraction time and isovolumic relaxation time divided by ejection time” („Tei-Index”) has been demonstrated to provide useful information about disease severity and prognosis in patients with dilated cardiomyopathy and cardiac amyloidosis. In patients with coronary artery disease (CAD), the diagnostic utility of this index is unclear. We attempted to validate the Tei-Index in CAD patients with overall cardiac or isolated diastolic dysfunction. Methods and results Sixty subjects were included who underwent left heart catheterization for invasive measurement of left ventricular end-diastolic pressure (LVEDP): 20 symptomatic CAD patients with overall cardiac dysfunction (defined by a LV ejection fraction (EF) <45% (mean 27±8%) and a LVEDP≥16mmHg, (mean 22±6mmHg), NYHA class 2.7±0.4, OCD group), 29 symptomatic CAD patients with isolated diastolic dysfunction (defined by an EF >45% (mean 55±8%), a normal end-diastolic diameter index (mean 2.8±0.4 cm/m2) and a LVEDP≥16mmHg (mean 22±6mmHg), NYHA class 2.3±0.4, IDD group) and 11 asymptomatic control subjects (EF 65±9%, LVEDP 11±4mmHg, CON group). After conventional 2-D- and Doppler echocardiographic examination, the Tei-Index was obtained.    The Tei-Index was easily and reproducibly measured in all study subjects. In the OCD group, isovolumic contraction time was prolonged and ejection time was shortened in comparison to the CON group, resulting in a significantly increased Tei-Index (0.71±0.28 vs 0.40±0.11, p<0.01). In the IDD group, isovolumic relaxation time was prolonged and isovolumic contraction time was shortened in comparison to controls, resulting in a largely unchanged Tei-Index (0.45±0.14, p=ns). Receiver operating characteristic curve analysis for the Tei-Index yielded an area under the curve of 0.92±0.04 for separating patients with vs without OCD. Using a Tei-Index >>;0.49 as a cut-off, OCD patients were identified with a sensitivity of 96% and a specificity of 86%. Conclusion The Tei-Index is a valid and readily derived indicator of global cardiac dysfunction in CAD patients with impaired systolic and diastolic LV performance. The use of this index seems to be limited in CAD patients with primary diastolic dysfunction.