Geert Kleinnibbelink

Chapter 6 150 PH patients above the cut-off point and the cut-off point (for dichotomous scales) or between the mean RVLS of the PH patients and the chosen amount of change in % strain (for continuous scales). The weighted mean relative reduction in RVLS and follow-up time was calculated by multiplying the relative % reduction of RVLS or months of follow-up with the number of included patients per study, after which the cumulative value was divided by the total number of patients included in each analysis. RESULTS Study selection During our search we identified 1,558 potential articles for inclusion. After removal of duplicates, 1,155 articles remained, from which title and abstract were screened for potential inclusion. Finally, a total of 42 studies were considered to be eligible for inclusion ( Figure 1 ). After carefully reading through the full-texts, we identified 12 studies that met our inclusion criteria. 7-11, 14, 15, 21, 23, 26, 28, 29 From these 12 studies, six provided data on all- cause mortality 9, 10, 14, 15, 23, 28 , from which one study did not report nor provide the results of multivariate analysis. 14 This study was therefore excluded from our meta-analysis. Seven studies reported data for the combined endpoint. 7, 8, 10, 11, 21, 26, 29 One study reported separate data for all-cause mortality and combined endpoint and was included for both analysis. 10 The remaining 11 studies included a total number of 1,169 patients with PH. Studies included predominantly female patients (range: 56-83%), with a mean age varying from 39 to 66 years. Details about the patient population, WHO class, NYHA class and study design of studies that were included are summarized in Table 3 . Study endpoints Studies that examined the combined endpoint included 821 patients with PH, with a follow-up time ranging from 0.6-3.8 years. PH-related events varied from hospitalizations for worsening of PH 7, 8, 10, 21 , lung transplantation 8, 10, 26 , atrial septostomy 8 , pulmonary endarterectomy 21 , balloon pulmonary angioplasty 21 and intensified PH medical therapy. 8, 11 Studies that explored all-cause mortality as the primary endpoint included a total of 399 patients with PH, with a follow-up time ranging from 2.0-3.8 years.