Occult left ventricular dysfunction diagnosed by myocardial performance index in patients with limb girdle muscle dystrophy: A case control study.

The myocardial performance index (MPI) was assessed in 30 patients with limb girdle muscle dystrophy (LGMD) with a normal left ventricular ejection fraction (greater than 50%), as well as in 30 age- and sex-matched healthy adults with a left ventricular ejection fraction greater than 50%. MPIs derived by pulsed-wave Doppler and tissue Doppler were also compared. The MPI was 0.