According to current guidelines, pulmonary arterial hypertension (PAH) is diagnosed when mean pulmonary arterial pressure (Ppa) exceeds 25 mmHg at rest or 30 mmHg during exercise. Issues that remain unclear are the classification of Ppa values ,25mmHg and whether Ppa .30 mmHg during exercise is always pathological.We performed a comprehensive literature review and analysed all accessible data obtained by right heart catheter studies from healthy individuals to determine normal Ppa at rest and during exercise. Data on 1,187 individuals from 47 studies in 13 countries were included. Data were stratified for sex, age, geographical origin, body position and exercise level.Ppa at rest was 14.0¡3.3 mmHg and this value was independent of sex and ethnicity. Resting Ppa was slightly influenced by posture (supine 14.0¡3.3 mmHg, upright 13.6¡3.1 mmHg) and age (,30 yrs: 12.8¡ 3.1mmHg; 30-50 yrs: 12.9¡3.0 mmHg; o50 yrs: 14.7¡4.0 mmHg). Ppa during exercise was dependent on exercise level and age. During mild exercise, Ppa was 19.4¡4.8 mmHg in subjects aged ,50 yrs compared with 29.4¡8.4 mmHg in subjects o50 yrs (p,0.001).In conclusion, while Ppa at rest is virtually independent of age and rarely exceeds 20 mmHg, exercise Ppa is age-related and frequently exceeds 30 mmHg, especially in elderly individuals, which makes it difficult to define normal Ppa values during exercise.

Pericytes are associated with the abluminal wall of microvessels, ie, arterioles, venules, and capillaries. They can be distinguished from other perivascular cell types by their location within the microvascular basement membrane. Pericytes, such as vascular smooth muscle cells (VSMCs; the mural cells of larger vessel), are mesenchymal cells of presumed mesodermal or neuroectodermal origin.

Background. Normothermic machine perfusion (NMP) bears the potential for significant prolongation of liver preservation before transplantation. Although safety and feasibility have been recently published, no data are available describing the significant challenges of establishing NMP programs outside clinical studies. We herein present our experience and propose a multidisciplinary approach for liver NMP in the clinical routine. Methods. In February 2018, liver NMP was introduced for routine use in marginal organs, logistic challenges, and complex recipients at our institution. In a multidisciplinary effort among transplant coordinators, perfusionists, transplant surgeons, anesthesia, nurses, blood bank as well as laboratory staff, a clinical routine was established and 34 NMP cases were performed without critical incidents or organ loss. Results. Nine livers were discarded due to poor organ quality and function observed during NMP. Twenty-five livers were successfully transplanted after preservation of up to 38 h. The extended criteria donors rate was 100% and 92% in discarded and transplanted livers, respectively. Nighttime procedures and parallel transplantations were eventually omitted. Graft and patient survival was 88% at 20 mo. No cholangiopathy was observed despite the use of extended criteria donor organs in 92% of cases. Conclusions. NMP in a multidisciplinary approach enables a safe prolongation of liver preservation and overnight organ care. A first field test of NMP indicates safety and benefit of this approach.

MPAP and resistance in the upper normal range at rest and moderate exercise are associated with decreased exercise capacity and may indicate early pulmonary vasculopathy in patients with systemic sclerosis. Investigations on the prognostic and therapeutic implications of such borderline findings are warranted. Clinical trial registered with http://www.clinicaltrials.gov (NCT00609349).