Right ventricular impairment in patients with chronic respiratory failure on home oxygen therapy - Non-invasive assessment using a new Doppler index

We evaluated the usefulness of the newly defined Doppler index combining sy stolic and diastolic myocardial performance, in assessing right-heart dysfu nction in 29 patients with chronic respiratory failure caused by old tuberc ulosis who were on 24-h home oxygen therapy. We measured tricuspid inflow v elocity, right-ventricular outflow velocity, late/early diastolic peak velo cities (A/E), the ratio between pre-ejection period and ejection time (PEP/ ET), and the new index of systolic and diastolic myocardial performance (SD MP) calculated as (isovolumetric contraction time + isovolumetric relaxatio n time)/ejection time. The calculated A/E, PEP/ET and SDMP in our patients were significantly higher than those in age-matched healthy subjects (n = 3 7, mean age 67 +/- 8 years). There was no overlap in the SDMP index between healthy subjects and patients and the index was not influenced by heart ra te. Our results suggest that SDMP index is a better marker than A/E and PEP /ET for the assessment of right-ventricular impairment.