Left ventricle myocardial performance index derived either by conventional method or mitral annulus tissue-Doppler: a comparison study in healthy subjects and subjects with heart failure.

Objectives: The aims of this study were to investigate the clinical agreement between myocardial performance index (MPI) measured conventionally and by pulsed-wave tissue Doppler (PW-TD) of the mitral annulus, and to test whether PW-TD MPI can accurately differentiate between healthy subjects and patients affected by congestive heart failure (CHF) with mild to moderate reduction of systolic function.
Background: Calculation of MPI using PW-TD may have advantages over conventional left ventricle inflow/outflow tract pulsed-wave Doppler (PWD) method; for example, all of the data needed for PW-TD MPI calculation can be derived from one single cardiac cycle, whereas with PWD at least two different cycles are needed. Thus, heart rate variability does not interfere with PW-TD MPI.
Methods and Results: In group A, we included 70 healthy adults with normal left ventricular ejection fraction and normal diastole, whereas for group B we studied 50 patients with CHF and left ventricular ejection fraction between 35% and 45%. MPI measured with PWD was statistically different (P < .0001) from MPI measured with PW-TD both in group A (0.33 +/- 0.09 vs 0.42 +/- 0.09) and group B (0.69 +/- 0.15 vs 0.79 +/- 0.12). Nonetheless, clinical agreement existed between the two methods in the single subject. Receiver operating characteristic curves showed very high accuracy for both methods to discriminate patients with CHF from healthy subjects; the optimal cutoff point was different and specific to each method: 0.50 for the conventional method and 0.60 for the PW-TD method.
Conclusion: We found clinical agreement between MPI measured in the same subject with the conventional PWD method and with PW-TD. Both methods had similarly high diagnostic accuracy for CHF, but this study supports the use of a higher MPI cut-point for best diagnostic accuracy when using the new PW-TD method.
Summary: We performed a study in healthy adults and in patients with congestive heart failure to investigate the clinical agreement between MPI measured conventionally and by PW-TD of the mitral annulus. We found mild agreement between MPI measured by the conventional method and by PW-TD. Both methods had high diagnostic accuracy for CHF. PW-TD method requires a higher MPI cut-point for best diagnostic accuracy.