Mortality in PPH is largely associated with hemodynamic variables that assess right ventricular function. The proposed prognostic equation had a high sensitivity and a relatively low specificity to predict survival in our PPH population. To improve this specificity it may be necessary to increase the limits of poor prognosis as defined by the equation.

Children with primary pulmonary hypertension have a poor survival expectancy, which does not appear to differ from that in adults with primary pulmonary hypertension. Mortality in childhood primary pulmonary hypertension is also associated with variables that assess right ventricular dysfunction.

In view of the recent advances in our understanding of the pathophysiology of COPD, we felt that it would be appropriate to examine the contribution of several abnormalities, not hitherto examined, to exercise limitation in this disease. These included: (1) The ability to exceed maximum expiratory flow (determined during forced maneuvers from TLC) during partial expiratory maneuvers. This is referred to as deltaFEV1. (2) Shape of the flow-volume curve (Shape). (3) Susceptibility to develop dynamic hyperinflation (dynamic hyperinflation index, DHI). (4) Ventilatory response to exercise (VEmax/VEpred). Twenty-four COPD patients (FEV1 = 42 +/- 13% pred) underwent symptom-limited progressive exercise. DeltaFEV1, shape, DHI and VEmax/VEpred were determined. All values were normalized to eliminate the effects of age, sex, and body size. Shape had no impact on peak VO2 (r = 0.8). DeltaFEV1 (r = 0.50), DHI (r = 0.50) and VEmax/VEpred (r = 0.46) correlated significantly with peak VO2 with all three exceeding FEV1 (r = 0.43). DHI and deltaFEV1 correlated significantly with each other (r = 0.43) suggesting that the latter exerts its beneficial effects by reducing the tendency to develop DH. We conclude that variability among patients in ventilatory response to exercise and in deltaFEV1 (likely an expression of extent of regional mechanical heterogeneity) contribute importantly to variability of exercise tolerance in COPD.

Chronic obstructive pulmonary disease (COPD) is a multicomponent disorder that leads to substantial disability, impaired quality of life, and increased mortality. Although the majority of COPD patients are first diagnosed and treated in primary care practices, there is comparatively little information on the management of COPD patients in primary care. A web-based pilot survey was conducted to evaluate the primary care physician’s, or general practitioner’s (GP’s), knowledge, understanding, and management of COPD in twelve territories across the Asia-Pacific region, Africa, eastern Europe, and Latin America, using a 10-minute questionnaire comprising 20 questions and translated into the native language of each participating territory. The questionnaire was administered to a total of 600 GPs (50 from each territory) involved in the management of COPD patients and all data were collated and analyzed by an independent health care research consultant. This survey demonstrated that the GPs’ understanding of COPD was variable across the territories, with large numbers of GPs having very limited knowledge of COPD and its management. A consistent finding across all territories was the underutilization of spirometry (median 26%; range 10%–48%) and reliance on X-rays (median 14%; range 5%–22%) for COPD diagnosis, whereas overuse of blood tests (unspecified) was particularly high in Russia and South Africa. Similarly, there was considerable underrecognition of the importance of exacerbation history as an important factor of COPD and its initial management in most territories (median 4%; range 0%–22%). Management of COPD was well below guideline-recommended levels in most of the regions investigated. The findings of this survey suggest there is a need for more ongoing education and information, specifically directed towards GPs outside of Europe and North America, and that global COPD guidelines appear to have limited reach and application in most of the areas studied.

The progression of chronic obstructive pulmonary disease (COPD) is generally associated with decreased exercise capacity. Differences in forced expired volume in 1 s (FEV1) among patients account for only a fraction of the variability in maximal oxygen consumption (VO2max). We hypothesized that variability in ventilatory response to exercise and in inspiratory mechanics and body mass index contributes importantly to variability in VO2max in this disease. We analyzed the files of 53 patients with established diagnosis of COPD who underwent a recent symptom-limited exercise test. We used inspiratory capacity and maximum inspiratory flow as measures of variability in inspiratory mechanics. The minute ventilation (VE) at the subject's VO2max was divided by the predicted in a normal subject at the same VO2 to obtain a ratio (VE,max/VE,pred). The ventilatory response during exercise provided the best correlation with peak VO2 (r = 0.62). FEV1 and inspiratory capacity also correlated with peak oxygen consumption but not as well as the ventilatory response (r = 0.49 and r = 0.46, respectively). Maximum inspiratory flow and body mass index showed only weak positive correlations (r = 0.23, not significant). The stepwise analysis generated the following equation: VO2max (%predicted) = (77.26 x VE,pred/VE,max) + [0.45 x FEV1 (%predicted)] - 23.66; r = 0.76, P < 0.001. We conclude that variability in the ventilatory response during exercise is one of the main determinants of variability in exercise capacity in COPD patients.