Proposed new pulmonary hypertension definition: is 4 mm(Hg) worth re-writing medical textbooks?

Medical Management of Pulmonary Arterial Hypertension: Current Approaches and Investigational Drugs

Pulmonary arterial hypertension (PAH) is a malignant pulmonary vascular syndrome characterized by a progressive increase in pulmonary vascular resistance and pulmonary arterial pressure, which eventually leads to right heart failure and even death. Although the exact mechanism of PAH is not fully understood, pulmonary vasoconstriction, vascular remodeling, immune and inflammatory responses, and thrombosis are thought to be involved in the development and progression of PAH. In the era of non-targeted agents, PAH had a very dismal prognosis with a median survival time of only 2.8 years. With the deep understanding of the pathophysiological mechanism of PAH as well as advances in drug research, PAH-specific therapeutic drugs have developed rapidly in the past 30 years, but they primarily focus on the three classical signaling pathways, namely the endothelin pathway, nitric oxide pathway, and prostacyclin pathway. These drugs dramatically improved pulmonary hemodynamics, cardiac function, exercise tolerance, quality of life, and prognosis in PAH patients, but could only reduce pulmonary arterial pressure and right ventricular afterload to a limited extent. Current targeted agents delay the progression of PAH but cannot fundamentally reverse pulmonary vascular remodeling. Through unremitting efforts, new therapeutic drugs such as sotatercept have emerged, injecting new vitality into this field. This review comprehensively summarizes the general treatments for PAH, including inotropes and vasopressors, diuretics, anticoagulants, general vasodilators, and anemia management. Additionally, this review elaborates the pharmacological properties and recent research progress of twelve specific drugs targeting three classical signaling pathways, as well as dual-, sequential triple-, and initial triple-therapy strategies based on the aforementioned targeted agents. More crucially, the search for novel therapeutic targets for PAH has never stopped, with great progress in recent years, and this review outlines the potential PAH therapeutic agents currently in the exploratory stage to provide new directions for the treatment of PAH and improve the long-term prognosis of PAH patients.

Impact of borderline pulmonary hypertension due to left heart failure on mortality in a multicenter registry study: A 3-year survivorship analysis

Background

Patients with left heart failure (LHF) are often associated with the development of pulmonary hypertension (PH) which leads to an increased risk of death. Recently, the diagnostic standard for PH has changed from mean pulmonary arterial pressure (mPAP) ≥25 mmHg to >20 mmHg. Nonetheless, the effect of borderline PH (mPAP: 21–24 mmHg) on the prognosis of LHF patients is unclear. This study aimed to investigate the relationship between borderline PH and 3-year clinical outcomes in LHF patients.

Methods

A retrospective analysis of a prospective cohort study was done for LHF patients who underwent right heart catheterization (RHC) between January 2013 and November 2016. The primary outcome was all-cause mortality; the secondary outcome was rehospitalization.

Results

Among 344 patients, 62.5% were identified with a proportion of PH (mPAP ≥ 25), 10.8% with borderline PH (21–24), and 26.7% with non-PH (≤20), respectively. Multivariable Cox analysis revealed that borderline PH patients had a higher adjusted mortality risk (HR = 3.822; 95% CI: 1.043–13.999; p = 0.043) than non-PH patients. When mPAP was treated as a continuous variable, the hazard ratio for death increased progressively with increasing mPAP starting at 20 mmHg (HR = 1.006; 95% CI: 1.001–1.012). There was no statistically significant difference in adjusted rehospitalization between borderline PH and non-PH patients (HR = 1.599; 95% CI: 0.833–3.067; p = 0.158).

Conclusions

Borderline PH is independently related to increased 3-year mortality in LHF patients. Future research is needed to evaluate whether more close monitoring, and managing with an intensifier improves clinical outcomes in borderline PH caused by LHF.

Clinical trials registration

www.clinicaltrials.gov NCT02164526.

The definition of pulmonary hypertension: history, practical implications and current controversies

The definition of pulmonary hypertension (PH) is based on a growing body of evidence and represents the result of ongoing discussions within the PH community over the past 50 years. In 2018, the most recent World Symposium on Pulmonary Hypertension introduced significant changes in the definition of PH by lowering the mean pulmonary arterial pressure threshold to >20 mmHg and (re)introducing the pulmonary vascular resistance ≥3 WU cut-off for all forms of pre-capillary PH. These changes and their potential clinical impact have been the subject of lively discussions in the community and some important questions and controversies have been identified.

In this review we aim to present the development of the definition of PH over the past decades and discuss the main arguments that led to relevant modifications. In addition, we address the practical implications of the most recent changes and controversies that still exist.

The definitions of PH and PAH reflect the upper limit of normal haemodynamic values, their prognostic relevance and practical considerations. With appropriate clinical context they represent the cornerstone of PH diagnosis and clinical decision making.https://bit.ly/3gRSyWz

Cardiac Output Determination in Precapillary Pulmonary Hypertension: A Systematic Review

BACKGROUND

Cardiac output determination is essential in precapillary pulmonary hypertension. While direct Fick is the gold standard, thermodilution is commonly used as the reference method. Moving to noninvasive methods would be highly beneficial for patients, avoiding repetitive invasive assessments. This systematic review followed 3 objectives: (1) assessing the validity of indirect Fick and thermodilution in precapillary pulmonary hypertension, (2) assessing the interchangeability of noninvasive cardiac output measurement methods against reference methods in precapillary pulmonary hypertension, and (3) detecting methodological heterogeneity in the included studies.

METHODS

We systematically reviewed the literature using medical databases and following PRISMA guidelines. We included articles comparing an invasive or noninvasive cardiac output measurement method with thermodilution or direct Fick in precapillary pulmonary hypertension patients. Cutoffs of limits of agreement and percentage error derived from the Bland and Altman graph were used to accept interchangeability. To study methodological heterogeneity, we extracted 9 quality criteria from all studies.

RESULTS

Eleven studies were included. None reached the suggested interchangeability criteria. The median number of the 9 assessed quality criteria was 2 with interquartile range (0-4).

CONCLUSIONS

Further studies evaluating the reliability of thermodilution and the consequences of its use in precapillary pulmonary hypertension patients are necessary. No evidence supports the use of indirect Fick in precapillary pulmonary hypertension. The studied noninvasive methods could not be considered interchangeable with invasive methods. A robust methodology should be used to draw sensible conclusions.

Impact of the new pulmonary hypertension definition on long-term mortality in patients with severe aortic stenosis undergoing valve replacement

Background

The new 2018 pulmonary hypertension (PH) definition includes a lower mean pulmonary artery pressure (mPAP) cut‐off (>20 mmHg rather than ≥25 mmHg) and the compulsory requirement of a pulmonary vascular resistance (PVR) ≥3 Wood units (WU) to define precapillary PH. We assessed the clinical impact of the 2018 compared to the 2015 PH definition in aortic stenosis (AS) patients undergoing aortic valve replacement (AVR).

Methods

Severe AS patients (n = 487) undergoing pre‐AVR right heart catheterization were classified according to the 2015 and 2018 definitions. Post‐AVR mortality (median follow‐up 44 months) was assessed.

Results

Based on the 2015 definition, 66 (13%) patients exhibited combined pre and postcapillary PH (CpcPH), 116 (24%) isolated post‐capillary PH (IpcPH), 28 (6%) precapillary PH, and 277 (57%) no PH at all. Overall, 52 (11%) patients were reclassified: 23 no PH into IpcPH; 8 no PH into precapillary PH; 20 precapillary PH into no PH; 1 CpcPH into IpcPH. By the 2015 definition, only CpcPH patients displayed increased mortality, whereas by the 2018 definition, precapillary PH patients also experienced higher mortality than those without PH. Among the PH definition components, PVR ≥3 WU was the strongest predictor of death (hazard ratio > 4).

Conclusions

In severe AS, a higher number of IpcPH patients are diagnosed by the 2018 definition, even though they have the same prognosis as those without PH. Patients with true precapillary PH are more accurately identified by the 2018 definition that includes a pulmonary vascular disease criterion, that is, PVR ≥3 WU, a strong mortality predictor.

How low should we go? Potential benefits and ramifications of the pulmonary hypertension hemodynamic definitions proposed by the 6th World Symposium

PURPOSE OF REVIEW

The 6th World Symposium on Pulmonary Hypertension (WSPH) proposed lowering the mean pulmonary artery pressure (mPAP) threshold that defines pulmonary hypertension from ≥ 25 to > 20 mmHg. The historical context and evolution of the pulmonary hypertension definition and the data used to rationalize recent changes are reviewed here.

RECENT FINDINGS

There are accumulating data on the clinical significance of mildly elevated mPAPs (21-24 mmHg). Studies have demonstrated lower exercise capacity and an increased risk of progression to overt pulmonary hypertension (mPAP ≥ 25 mmHg) in specific at-risk patient populations. Further, large registries across diverse pulmonary hypertension populations have identified increased mortality in patients with mPAPs 21-24 mmHg. Although the clinical sequelae of lowering the mPAP threshold remain unclear, this uncertainty has fueled recent debates within the pulmonary hypertension community.

SUMMARY

The changes to the pulmonary hypertension definition proposed by the 6th WSPH are supported by normative hemodynamic data in healthy individuals as well as studies demonstrating an association between mPAPs above this normal range and increased mortality. Whether the higher mortality observed in patients with mildly elevated mPAPs is directly attributable to pulmonary vascular disease that is amenable to therapeutic intervention remains to be determined.

Mildly Elevated Pulmonary Arterial Pressure Is Associated With a High Risk of Progression to Pulmonary Hypertension and Increased Mortality: A Systematic Review and Meta-Analysis

Background

Pulmonary hypertension (PH) is defined as a mean pulmonary arterial pressure (PAP) ≥25 mm Hg measured by right heart catheterization. However, the upper limit of a normal mean PAP is 20 mm Hg. There is a gap between the upper limit of normal and the threshold for diagnosing PH. Therefore, we aimed to investigate whether individuals with a mildly elevated PAP, defined as 20 mm Hg < mean PAP <25 mm Hg, are at an increased risk of progression to PH or mortality than those with a normal PAP.

Methods and Results

We reviewed studies evaluating the risk of progression to PH and/or mortality in individuals with a mildly elevated PAP versus those with a normal PAP. The mean PAP value of each participant was confirmed by right heart catheterization. We reviewed 1213 studies and 8 fulfilled our inclusion criteria. Our results indicated that individuals with a mildly elevated PAP were 1.81 to 2.45 times more likely to progress to PH than individuals with a normal PAP. There was a statistically significant difference in mortality between the mildly elevated PAP and normal PAP groups (hazard ratio, 2.48; 95% CI, 1.69–3.64). We also pooled survival probabilities in each arm to obtain a summary survival curve for each group, and the pooled survival rates in the mildly elevated PAP group were numerically lower than those in the normal PAP group.

Conclusions

Our study revealed that individuals with a mildly elevated PAP were at an increased risk of progression to PH and mortality than those with a normal PAP.

Impact of the updated hemodynamic definitions on diagnosis rates of pulmonary hypertension

We evaluated whether updated pulmonary hypertension definitive criteria proposed in sixth World Symposium on Pulmonary Hypertension had an impact on diagnosis of overall pulmonary hypertension and pre-capillary and combined pre- and post-capillary phenotypes as compared to those in European Society of Cardiology/European Respiratory Society 2015 pulmonary hypertension Guidelines. Study group comprised the retrospectively evaluated 1300 patients (age 53.1 ± 18.8 years, female 807, 62.1%) who underwent right heart catheterization with different indications between 2006 and 2018. Mean pulmonary arterial pressure ≥25 mmHg (European Society of Cardiology) and PAMP (mean pulmonary arterial pressure) >20 mmHg (World Symposium on Pulmonary Hypertension) right heart catheterization definitions criteria were used, respectively. For pre-capillary pulmonary hypertension, pulmonary artery wedge pressure ≤15 mmHg and pulmonary vascular resistance ≥3 Wood units criteria were included in the both definitions. Normal mean pulmonary arterial pressure (<21 mmHg), borderline mean pulmonary arterial pressure elevation (21–24 mmHg), and overt pulmonary hypertension (≥25 mmHg) were documented in 21.1, 9.8, and 69.1% of the patients, respectively. The pre-capillary and combined pre- and post-capillary pulmonary hypertension were noted in 2.9 and 1.1%, 8.7 and 2.5%, and 34.6 and 36.6% of the patients with normal mean pulmonary arterial pressure, borderline, and overt pulmonary hypertension subgroups, respectively. The World Symposium on Pulmonary Hypertension versus European Society of Cardiology/European Respiratory Society definitions resulted in a net 9.8% increase in the diagnosis of overall pulmonary hypertension whereas increases in the pre-capillary pulmonary hypertension and combined pre- and post-capillary pulmonary hypertension diagnosis were only 0.8 and 0.3%, respectively. The re-definition of mean pulmonary arterial pressure threshold seems to increase the frequency of the overall pulmonary hypertension diagnosis. However, this increase was mainly originated from those in post-capillary pulmonary hypertension subgroup whereas its impact on pre-capillary and combined pre- and post-capillary pulmonary hypertension was negligible. Moreover, criteria of pre-capillary pulmonary vascular disease and combined pre- and post-capillary phenotypes were still detectable even in the presence of normal mean pulmonary arterial pressure. The obligatory criteria of pulmonary vascular resistance ≥3 Wood units seems to keep specificity for discrimination between pre-capillary versus post-C pulmonary hypertension after lowering the definitive mean pulmonary arterial pressure threshold to 20 mmHg.

Mean platelet volume combined red cell distribution width as biomarker of chronic obstructive pulmonary disease with pulmonary heart disease

BACKGROUND AND OBJECTIVE

Platelet activation, inflammatory reactions and oxidative stress are common pathogenesis of chronic obstructive pulmonary disease (COPD) with pulmonary heart disease (PHD). Mean platelet volume (MPV) and red blood cell distribution width (RDW) form part of the pathomechanisms of these conditions. Here, we investigated whether MPV and RDW can be biomarkers of PHD occurring secondary to COPD.

MATERIALS AND METHODS

This was a retrospective study on 229 participants with COPD. Among them, 69 had PHD. Complete blood count (CBC), blood gas analysis, pulmonary function tests and echocardiography were analyzed.

RESULTS

MPV and RDW-standard deviation (RDW-SD) were significantly higher in patients with PHD than in patients without PHD (P ≤ 0.001). MPV and RDW-SD were positively correlated with pulmonary artery pressure (PAP) and the size of the right ventricle (P ≤ 0.05). Multivariate regression analysis showed that the risk of PHD increased 3-fold per unit rise in MPV (OR = 2.901, P ≤ 0.001). We observed that the risk of PHD increased 1.5 times per unit rise in RDW-SD (OR = 1.371, P ≤ 0.001).The AUC of ROC curve for the combined MPV and RDW-SD in predicting PHD among COPD patients was 0.900 (95％CI: 0.846-0．954, P ≤ 0.001), with a sensitivity of 76.8% and a specificity of 99.4%.

CONCLUSIONS

Both MPV and RDW-SD were significantly elevated and correlated with disease severity in COPD patients with PHD. A combination of these two parameters presents an effective biomarker of PHD.

Pulmonary vascular resistance and clinical outcomes in patients with pulmonary hypertension: a retrospective cohort study

BACKGROUND

In pulmonary hypertension subgroups, elevated pulmonary vascular resistance (PVR) of 3·0 Wood units or more is associated with poor prognosis. However, the spectrum of PVR risk in pulmonary hypertension is not known. To address this area of uncertainty, we aimed to analyse the relationship between PVR and adverse clinical outcomes in pulmonary hypertension.

METHODS

We did a retrospective cohort study of all patients undergoing right heart catheterisation (RHC) in the US Veterans Affairs health-care system (Oct 1, 2007-Sep 30, 2016). Patients were included in the analyses if data from a complete RHC and at least 1 year of follow-up were available. Both inpatients and outpatients were included, but individuals with missing mean pulmonary artery pressure (mPAP), pulmonary artery wedge pressure, or cardiac output were excluded. The primary outcome measure was time to all-cause mortality assessed by the Veteran Affairs vital status file. Cox proportional hazards models were used to assess the association between PVR and outcomes, and the mortality hazard ratio was validated in a RHC cohort from Vanderbilt University Medical Center (Sept 24, 1998-June 1, 2016).

FINDINGS

The primary cohort (N=40 082; 38 751 [96·7%] male; median age 66·5 years [IQR 61·1-73·5]; median follow-up 1153 days [IQR 570-1971]), included patients with a history of heart failure (23 201 [57·9%]) and chronic obstructive pulmonary disease (13 348 [33·3%]). We focused on patients at risk for pulmonary hypertension based on a mPAP of at least 19 mm Hg (32 725 [81·6%] of 40 082). When modelled as a continuous variable, the all-cause mortality hazard for PVR was increased at around 2·2 Wood units compared with PVR of 1·0 Wood unit. Among patients with a mPAP of at least 19 mm Hg and pulmonary artery wedge pressure of 15 mm Hg or less, the adjusted hazard ratio (HR) for mortality was 1·71 (95% CI 1·59-1·84; p<0·0001) and for heart failure hospitalisation was 1·27 (1·13-1·43; p=0·0001), when comparing PVR of 2·2 Wood units or more to less than 2·2 Wood units. The validation cohort (N=3699, 1860 [50·3%] male, median age 60·4 years [49·5-69·2]; median follow-up 1752 days [IQR 1281-2999]) included 2870 patients [77·6%] with mPAP of at least 19 mm Hg (1418 [49·4%] male). The adjusted mortality HR for patients in the mPAP of 19 mm Hg or more group and with PVR of 2·2 Wood units or more and pulmonary artery wedge pressure of 15 mm or less Hg (1221 [42·5%] of 2870) was 1·81 (95% CI 1·33-2·47; p=0·0002).

INTERPRETATION

These data widen the continuum of clinical risk for mortality and heart failure in patients referred for RHC with elevated pulmonary artery pressure to include PVR of around 2.2 Wood units and higher. Testing the generalisability of these findings in at-risk populations with fewer cardiopulmonary comorbidities is warranted.

FUNDING

None.

Diagnosis and Management of Pulmonary Hypertension in the Modern Era: Insights from the 6th World Symposium

The past 20 years have seen major advances in the diagnosis and management of pulmonary hypertension, a disease associated with significant morbidity and mortality. The 6th World Symposium in Pulmonary Hypertension (WSPH) took place in February 2018 and attempted to consolidate the current knowledge in the field into practical recommendations to help prioritize an action plan to improve patient outcomes and identify future research directions. In this review, we will summarize the highlights of the 6th WSPH proceedings, including revisions to the hemodynamic definitions and classification of the various types of pulmonary hypertension, genetic advances, approaches to risk stratification, and updated treatment algorithms.

Soluble Guanylate Cyclase Stimulators for Chronic Thromboembolic Pulmonary Hypertension Patients Treatment: New Data

This narrative review describes and appraises some relatively new studies investigating the efficacy and safety profile of soluble guanylate cyclase stimulator riociguat in patients suffering from pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH). It has been a while since the publication date of pivotal CHEST-1 trial in 2013. New studies available complement existing evidence, expound on specific questions and open new frontiers for CTEPH investigations going forward. In this paper authors attempted to present data from post-hocanalysis of the CHEST-1 study and real-world data on riociguat treatment, confirming the positive effect of the drug on hemodynamic parameters of the pulmonary circulation and the functional status of patients. This effect was shown previously in large randomized trials. The extremely important positive effect of riociguat demonstrated both in the group of inoperable patients with CTEPH and in patients with residual pulmonary hypertension after pulmonary thrombendarterectomy. Of great interest are the presented some authors results of reverse remodelling of the right heart chambers during riociguat therapy in CTEPH patients, including using unique imaging methods (magnetic resonance imaging and positron emission tomography) to evaluate targeted medicinal therapy in terms of right heart remodelling. The safety profile of the drug was analyzed in the long-term post-registration international, multicenter, prospective, observational study EXPERT (NCT02092818), which confirmed the good tolerability and safety of riociguat therapy in PAH and CTEPH patients.

Diagnostic accuracy of transthoracic echocardiography for pulmonary hypertension: a systematic review and meta-analysis

OBJECTIVE

To evaluate the diagnostic accuracy of transthoracic echocardiography (TTE) in patients with pulmonary hypertension (PH).

DESIGN

Systematic review and meta-analysis.

DATA SOURCES AND ELIGIBILITY CRITERIA

Embase, Cochrane Library for clinical trials, PubMed and Web of Science were used to search studies from inception to 19 June, 2019. Studies using both TTE and right heart catheterisation (RHC) to diagnose PH were included.

MAIN RESULTS

A total of 27 studies involving 4386 subjects were considered as eligible for analysis. TTE had a pooled sensitivity of 85%, a pooled specificity of 74%, a pooled positive likelihood ratio of 3.2, a pooled negative likelihood ratio of 0.20, a pooled diagnostic OR of 16 and finally an area under the summary receiver operating characteristic curve of 0.88. The subgroup with the shortest time interval between TTE and RHC had the best diagnostic effect, with sensitivity, specificity and area under the curve (AUC) of 88%, 90% and 0.94, respectively. TTE had lower sensitivity (81%), specificity (61%) and AUC (0.73) in the subgroup of patients with definite lung diseases. Subgroup analysis also showed that different thresholds of TTE resulted in a different diagnostic performance in the diagnosis of PH.

CONCLUSION

TTE has a clinical value in diagnosing PH, although it cannot yet replace RHC considered as the gold standard. The accuracy of TTE may be improved by shortening the time interval between TTE and RHC and by developing an appropriate threshold. TTE may not be suitable to assess pulmonary arterial pressure in patients with pulmonary diseases.

PROSPERO REGISTRATION NUMBER

PROSPERO CRD42019123289.

The revised definition of pulmonary hypertension: exploring the impact on patient management

At the 6th World Symposium on Pulmonary Hypertension (PH), it was proposed that the mean pulmonary arterial pressure (mPAP) threshold used to define PH should be lowered from ≥25 mmHg to >20 mmHg. The rationale for this change is that the ≥25 mmHg threshold is arbitrary, whereas the revised threshold is based on scientific evidence. For the definition of all forms of pre-capillary PH, the inclusion of a pulmonary vascular resistance (PVR) ≥3 Wood Units was also proposed, placing greater emphasis on an elevated PVR to identify pulmonary vascular disease. Here, we discuss the possible impact of the revised definition of PH on future clinical management. This change may facilitate earlier PH detection, particularly in at-risk patient groups that are already undergoing screening programmes, e.g. those with systemic sclerosis or mutations associated with PH. As an mPAP above the upper limit of normal (>20 mmHg) but <25 mmHg is associated with increased risk of morbidity and mortality compared with a normal mPAP, early identification of patients in this group is important to enable close monitoring and timely treatment initiation once clinically indicated. Treatments currently approved for PH are not necessarily suitable for patients with an mPAP 21-24 mmHg, as the management of this group has not been widely examined. The revised definition may facilitate inclusion of these patients in prospective trials, allowing the evaluation of appropriate management strategies.

Pulmonary hypertension in paediatrics. A feasible approach to bridge the gap between real world and guidelines

Pulmonary hypertension (PH) is quite infrequent in paediatric age and its most common aetiologies include idiopathic pulmonary arterial hypertension, PH related to congenital heart diseases, bronchopulmonary dysplasia (chronic lung disease), persistence of pulmonary hypertension of the newborn, and congenital diaphragmatic hernia. The developed for adult patients PH classification shows limitations when applied to paediatric subjects, since the underlying causes are markedly different between the two ages. In 2011, the Pulmonary Vascular Research Institute Panama Task Force outlined the first specific paediatric pulmonary hypertensive vascular disease diagnostic classification, including 10 main categories and 109 subcategories, thus testifying PH complex pathophysiology during newborns/children growth and development. The unique, distinctive features of paediatric PH were recognized also during the fifth World Symposium on Pulmonary hypertension in 2013 and then confirmed in the recent 2018 sixth World Symposium. For the sake of uniformity, an attempt to adapt the adult classification to paediatric patients was made. However, all these commendable classifications are very complex and may be not of quick comprehension for clinicians. A clinical simpler and simplified method is now suggested, comprising only five groups: Neonatal, Cardiac, Developmental, Idiopathic, and Syndromic PH. This approach is not aimed at replacing the already existing classifications, but is mainly based on the kind of specialized physician (neonatologist, paediatric cardiologist, paediatrician, pulmonologist, general practitioner) who first faces and looks after the child with suspected PH. What is dramatically known is that paediatric PH is a severe disease which, when untreated or undertreated, may lead to increased morbidity and mortality.

Mean platelet volume as a predictor of pulmonary hypertension in patients with stable COPD

Background: Pulmonary hypertension (PH) is one of the most common complications developed during the course of chronic obstructive pulmonary disease (COPD). Platelet activation plays an important role in its pathophysiology, and mean platelet volume (MPV) is considered a respectable index of platelet activation. The aim of this work is to assess the ability of MPV in predicting PH secondary to COPD as well as its severity.

Methods: A cross-sectional study was conducted on 228 stable COPD patients. CBC, echocardiography, and pulmonary function tests were performed.

Results: The prevalence of PH in stable COPD patients was high (63%), and the majority of patients had a mild degree (33%). There was no significant association between PH presence with different COPD grade, but, in very severe COPD, severe PH was significantly presented. MPV in COPD patients with PH was significantly higher than those without (9.02±1.14 vs 7.11±0.98, P<0.001). Moreover, a significant statistical rising of MPV with increased severity of PH. Multivariate regression analysis of predictors of PH demonstrated that; MPV is a real predictor of PH in such patients. The likelihood probability of PH increased up to 7-times with increasing one unit of MPV; (OR=6.7). A cut-off value of MPV >7.25 had 96% sensitivity and 76% specificity in predicting PH.

Conclusion: MPV was higher in COPD patients with PH and positively correlated with PH severity. If the data are to be confirmed, MPV may be taken into consideration in decision-making and management of COPD patients.