Elevated Pulmonary Artery Pressure: Results (Part 4)
To determine whether the predictive value of PAMP was relevant in patients with normal coronary arteriograms, further Cox regression analyses were carried out in this subgroup. (At baseline, 629 patients had normal coronary arteries and 23 fatal events were recorded during the follow-up period.) Pulmonary artery mean pressure was found to be the only hemodynamic variable among those described above that retained its predictive value (p=0.016) in these patients. In this analysis, number of vessels was not included in the model, of course, while LVEDP, LVEF, and right atrial pressure contributed no statistically significant information regarding prognosis. proventil inhaler
To estimate the magnitude of the effect of increased pulmonary pressure on survival, Kaplan-Meir product limit survival curves were constructed to compare patients with and without pulmonary pressures above 20 mm Hg (Fig 1). Survival differences for these two groups appeared early in the course of the follow-up and were highly significant (p<0.01). Survival at an interval of four years was 91 percent (95 percent confidence interval [Cl] = ±2) among patients with normal pulmonary pressures, and 82 percent (Cl = ± 2) among those with mean pressures equal to or greater than 20 mm Hg.
Figure 1. Survival among patients with normal and elevated pulmonary artery (PA) pressures (Kaplan-Meir product limit curves).