The relevant echocardiographic parameters were measured in both subject groups: myocardial performance index (MPI), isovolumic relaxation time (IRT), isovolumic contraction time (ICT), pre-ejection period (PEP), ejection time (ET), PEP/ET ratio, deceleration time (DT) and acceleration time (AT).
Pre-ejection period to ejection time (PEP/ET) ratio and deceleration time (DT) are other indices of systolic and diastolic function that have been investigated (10, 11) and correlated to radionuclide examination and cardiac catheterization (12).
Echocardiographic examination showed normal left ventricular function in all, whereas 27% of the natives at an altitude of 4,500 to 5,000 m had evidence of pulmonary hypertension and rise of normalized right ventricular pre-ejection period
The same measurements were taken three months later and the results showed that as the ICG measurements of left ventricular ejection time (LVET), pre-ejection period
(PEP) and systolic time ratio (STR) improved, so did the measurements of quality of life and NYHA class assessment.