Clinical Characteristics of Patients Undergoing Right Heart Catheterizations in Community Hospitals.

Background Recognition of precapillary pulmonary hypertension (PH) has significant implications for patient management. However, the low a priori chance to find this rare condition in community hospitals may create a barrier against performing a right heart catheterization (RHC). This could result in misclassification of PH and delayed diagnosis/treatment of precapillary PH. Therefore, we investigated patient characteristics and echocardiographic parameters associated with the decision whether to perform an RHC in patients with incident PH in 12 Dutch community hospitals. Methods and Results In total, 275 patients were included from the OPTICS (Optimizing PH Diagnostic Network in Community Hospitals) registry, a prospective cohort study with patients with incident PH; 157 patients were diagnosed with RHC (34 chronic thromboembolic PH, 38 pulmonary arterial hypertension, 81 postcapillary PH, 4 miscellaneous PH), while 118 patients were labeled as probable postcapillary PH without hemodynamic confirmation. Multivariable analysis showed that older age (>60 years), left ventricular diastolic dysfunction grade 2-3, left atrial dilatation were independently associated with the decision to not perform an RHC, while presence of prior venous thromboembolic events or pulmonary arterial hypertension-associated conditions, right atrial dilatation, and tricuspid regurgitation velocity ≥3.7 m/s favor an RHC performance. Conclusions Older age and echocardiographic parameters of left heart disease were independently associated with the decision to not perform an RHC, while presence of prior venous thromboembolic events or pulmonary arterial hypertension-associated conditions, right atrial dilation, and severe PH on echocardiography favored an RHC performance. As such, especially elderly patients may be at an increased risk of diagnostic delays and missed diagnoses of treatable precapillary PH, which could lead to a worse prognosis.

Imatinib in patients with severe COVID-19: a randomised, double-blind, placebo-controlled, clinical trial.

BACKGROUND: The major complication of COVID-19 is hypoxaemic respiratory failure from capillary leak and alveolar oedema. Experimental and early clinical data suggest that the tyrosine-kinase inhibitor imatinib reverses pulmonary capillary leak. METHODS: This randomised, double-blind, placebo-controlled, clinical trial was done at 13 academic and non-academic teaching hospitals in the Netherlands. Hospitalised patients (aged ≥18 years) with COVID-19, as confirmed by an RT-PCR test for SARS-CoV-2, requiring supplemental oxygen to maintain a peripheral oxygen saturation of greater than 94% were eligible. Patients were excluded if they had severe pre-existing pulmonary disease, had pre-existing heart failure, had undergone active treatment of a haematological or non-haematological malignancy in the previous 12 months, had cytopenia, or were receiving concomitant treatment with medication known to strongly interact with imatinib. Patients were randomly assigned (1:1) to receive either oral imatinib, given as a loading dose of 800 mg on day 0 followed by 400 mg daily on days 1-9, or placebo. Randomisation was done with a computer-based clinical data management platform with variable block sizes (containing two, four, or six patients), stratified by study site. The primary outcome was time to discontinuation of mechanical ventilation and supplemental oxygen for more than 48 consecutive hours, while being alive during a 28-day period. Secondary outcomes included safety, mortality at 28 days, and the need for invasive mechanical ventilation. All efficacy and safety analyses were done in all randomised patients who had received at least one dose of study medication (modified intention-to-treat population). This study is registered with the EU Clinical Trials Register (EudraCT 2020-001236-10). FINDINGS: Between March 31, 2020, and Jan 4, 2021, 805 patients were screened, of whom 400 were eligible and randomly assigned to the imatinib group (n=204) or the placebo group (n=196). A total of 385 (96%) patients (median age 64 years [IQR 56-73]) received at least one dose of study medication and were included in the modified intention-to-treat population. Time to discontinuation of ventilation and supplemental oxygen for more than 48 h was not significantly different between the two groups (unadjusted hazard ratio [HR] 0·95 [95% CI 0·76-1·20]). At day 28, 15 (8%) of 197 patients had died in the imatinib group compared with 27 (14%) of 188 patients in the placebo group (unadjusted HR 0·51 [0·27-0·95]). After adjusting for baseline imbalances between the two groups (sex, obesity, diabetes, and cardiovascular disease) the HR for mortality was 0·52 (95% CI 0·26-1·05). The HR for mechanical ventilation in the imatinib group compared with the placebo group was 1·07 (0·63-1·80; p=0·81). The median duration of invasive mechanical ventilation was 7 days (IQR 3-13) in the imatinib group compared with 12 days (6-20) in the placebo group (p=0·0080). 91 (46%) of 197 patients in the imatinib group and 82 (44%) of 188 patients in the placebo group had at least one grade 3 or higher adverse event. The safety evaluation revealed no imatinib-associated adverse events. INTERPRETATION: The study failed to meet its primary outcome, as imatinib did not reduce the time to discontinuation of ventilation and supplemental oxygen for more than 48 consecutive hours in patients with COVID-19 requiring supplemental oxygen. The observed effects on survival (although attenuated after adjustment for baseline imbalances) and duration of mechanical ventilation suggest that imatinib might confer clinical benefit in hospitalised patients with COVID-19, but further studies are required to validate these findings. FUNDING: Amsterdam Medical Center Foundation, Nederlandse Organisatie voor Wetenschappelijk Onderzoek/ZonMW, and the European Union Innovative Medicines Initiative 2.

Spectrum of Vascular Involvement in Coronavirus Disease 2019 Pneumonia-Findings on CT Perfusion.

OBJECTIVES: There is accumulating evidence of a distinct coagulopathy in severe acute respiratory syndrome coronavirus 2 infection which is associated with poor prognosis in coronavirus disease 2019. Coagulation abnormalities in blood samples resemble systemic coagulopathies in other severe infections but demonstrate specific features such as a very high d-dimer. These clinical observations are consistent with histopathologic findings of locally disturbed pulmonary microvascular thrombosis and angiopathy in end-stage coronavirus disease 2019. However, exact underlying processes and the sequence of events are not fully understood. DATA SOURCES: CT perfusion may provide insight in the dynamic aspect of the vascularity in pulmonary lesions in coronavirus disease 2019 infection as, in contrast to dual energy CT, a multiphase perfusion pattern is displayed. STUDY SELECTION: In six patients with coronavirus disease 2019 pneumonia, findings on additional CT perfusion series were correlated with known histopathologic vascular patterns upon pulmonary autopsy of patients who had died of coronavirus disease 2019. DATA EXTRACTION: In this case series, we were able to show perfusion changes on CT scans in typical pulmonary lesions illustrating diverse patterns. DATA SYNTHESIS: We demonstrated hyperperfusion in areas with ground glass and a severely decreased perfusion pattern in more consolidated areas often seen later in the course of disease. A combination was also observed, illustrating temporal heterogeneity. CONCLUSIONS: These findings provide new insights into the pathophysiology of coronavirus disease 2019 pneumonia and further understanding of the mechanisms that lead to respiratory failure in these patients.

Noninvasive Prediction of Elevated Wedge Pressure in Pulmonary Hypertension Patients Without Clear Signs of Left-Sided Heart Disease: External Validation of the OPTICS Risk Score.

Background Although most newly presenting patients with pulmonary hypertension (PH) have elevated pulmonary artery wedge pressure, identification of so-called postcapillary PH can be challenging. A noninvasive tool predicting elevated pulmonary artery wedge pressure in patients with incident PH may help avoid unnecessary invasive diagnostic procedures. Methods and Results A combination of clinical data, ECG, and echocardiographic parameters was used to refine a previously developed left heart failure risk score in a retrospective cohort of pre- and postcapillary PH patients. This updated score (renamed the OPTICS risk score) was externally validated in a prospective cohort of patients from 12 Dutch nonreferral centers the OPTICS network. Using the updated OPTICS risk score, the presence of postcapillary PH could be predicted on the basis of body mass index ≥30, diabetes mellitus, atrial fibrillation, dyslipidemia, history of valvular surgery, sum of SV1 (deflection in V1 in millimeters) and RV6 (deflection in V6 in millimeters) on ECG, and left atrial dilation. The external validation cohort included 81 postcapillary PH patients and 66 precapillary PH patients. Using a predefined cutoff of >104, the OPTICS score had 100% specificity for postcapillary PH (sensitivity, 22%). In addition, we investigated whether a high probability of heart failure with preserved ejection fraction, assessed by the H2FPEF score (obesity, atrial fibrillation, age >60 yrs, ≥2 antihypertensives, E/e' >9, and pulmonary artery systolic pressure by echo >35 mmHg), similarly predicted the presence of elevated pulmonary artery wedge pressure. High probability of heart failure with preserved ejection fraction (H2FPEF score ≥6) was less specific for postcapillary PH. Conclusions In a community setting, the OPTICS risk score can predict elevated pulmonary artery wedge pressure in PH patients without clear signs of left-sided heart disease. The OPTICS risk score may be used to tailor the decision to perform invasive diagnostic testing.

Membrane diffusion- and capillary blood volume measurements are not useful as screening tools for pulmonary arterial hypertension in systemic sclerosis: a case control study.

BACKGROUND: There is no optimal screening tool for the assessment of pulmonary arterial hypertension (PAH) in patients with systemic sclerosis (SSc). A decreasing transfer factor of the lung for CO (TLCO) is associated with the development of PAH in SSc. TLCO can be partitioned into the diffusion of the alveolar capillary membrane (Dm) and the capillary blood volume (Vc). The use of the partitioned diffusion to detect PAH in SSc is not well established yet. This study evaluates whether Dm and Vc could be candidates for further study of the use for screening for PAH in SSc. METHODS: Eleven SSc patients with PAH (SScPAH+), 13 SSc patients without PAH (SScPAH-) and 10 healthy control subjects were included. Pulmonary function testing took place at diagnosis of PAH. TLCO was partitioned according to Roughton and Forster. As pulmonary fibrosis in SSc influences values of the (partitioned) TLCO, these were adjusted for fibrosis score as assessed on HRCT. RESULTS: TLCO as percentage of predicted (%) was lower in SScPAH+ than in SScPAH- (41 +/- 7% vs. 63 +/- 12%, p < 0.0001, respectively). Dm% in SScPAH+ was decreased as compared with SScPAH- (22 +/- 6% vs. 39 +/- 12%, p < 0.0001, respectively), also after adjustment for total fibrosis score (before adjustment: B = 17.5, 95% CI 9.0-25.9, p = < 0.0001; after adjustment: B = 14.3, 95% CI 6.0-21.7, p = 0.008). No difference was found in Vc%. There were no correlations between pulmonary hemodynamic parameters and Dm% in the PAH groups. CONCLUSION: SScPAH+ patients have lower Dm% than SScPAH- patients. There are no correlations between Dm% and hemodynamic parameters of PAH in SScPAH+. These findings do not support further study of the role of partitioning TLCO in the diagnostic work- up for PAH in SSc.

Immunopathological aspects of schistosomiasis-associated pulmonary arterial hypertension.

OBJECTIVES: Pulmonary hypertension is a lethal complication of chronic hepatosplenic schistosomiasis. Little is known of the underlying (immuno-)histopathological characteristics of lung vasculopathy. METHODS: We characterized vasculopathy and inflammation in lung tissue of 10 patients with Schistosomiasis-associated PH (SCH-PH) in comparison to 22 idiopathic pulmonary arterial hypertension (IPAH) patients and 10 normal controls. SCH-PH cases were younger than controls. RESULTS: Plexiform lesions and/or angiomatoid lesions were found in 10/10 SCH-PH, and 19/22 IPAH patients (χ² p = 0.22). Lung granulomas with Schistosoma eggs were found in 2/10 of SCH-PH cases. PAH cases had increased peri-arterial density of CD3+ T cells, chymase+ and tryptase+ mast cells when compared to controls (p ≤ 0.047). SCH-PH showed increased density of CD4+ cells when compared to controls (p = 0.025), paralleled by an increased density of dendritic CD83+ cells when compared to both controls and IPAH patients (p ≤ 0.022). CONCLUSION: Both SCH-PH and IPAH feature plexogenic arteriopathy and increased periarterial T cell and mast cell density. SCH-PH and IPAH differ only with respect to the density of dendritic CD83+ cells. These findings imply ongoing antigenic stimulation in SCH-PH, yet a pattern of pulmonary vasculopathy similar to IPAH, suggestive of a final common pathway in their pathogenesis of PAH.

Lung membrane conductance and capillary volume derived from the NO and CO transfer in high-altitude newcomers.

Acute exposure to high altitude may induce changes in carbon monoxide (CO) membrane conductance (DmCO) and capillary lung volume (Vc). Measurements were performed in 25 lowlanders at Brussels (D0), at 4,300 m after a 2- or 3-day exposure (D2,3) without preceding climbing, and 5 days later (D7,8), before and after an exercise test, under a trial with two arterial pulmonary vasodilators or a placebo. The nitric oxide (NO)/CO transfer method was used, assuming both infinite and finite values to the NO blood conductance (θNO). Doppler echocardiography provided hemodynamic data. Compared with sea level, lung diffusing capacity for CO increased by 24% at D2,3 and is returned to control at D7,8. The acute increase in lung diffusing capacity for CO resulted from increases in DmCO and Vc with finite and infinite θNO assumptions. The alveolar volume increased by 16% at D2,3 and normalized at D7,8. The mean increase in systolic arterial pulmonary pressure at rest at D2,3 was minimal. In conclusion, the acute increase in Vc may be related to the increase in alveolar volume and to the increase in capillary pressure. Compared with the infinite θNO value, the use of a finite θNO value led to about a twofold increase in DmCO value and to a persistent increase in DmCO at D7,8 compared with D0. After exercise, DmCO decreased slightly less in subjects treated by the vasodilators, suggesting a beneficial effect on interstitial edema.

Platelet-derived growth factor receptor-ß and epidermal growth factor receptor in pulmonary vasculature of systemic sclerosis-associated pulmonary arterial hypertension versus idiopathic pulmonary arterial hypertension and pulmonary veno-occlusive disease: a case-control study.

INTRODUCTION: Systemic sclerosis (SSc) complicated by pulmonary arterial hypertension (PAH) carries a poor prognosis, despite pulmonary vascular dilating therapy. Platelet-derived growth factor receptor-ß (PDGFR-ß) and epidermal growth factor receptor (EGFR) are potential therapeutic targets for PAH because of their proliferative effects on vessel remodelling. To explore their role in SScPAH, we compared PDGFR- and EGFR-mmunoreactivity in lung tissue specimens from SScPAH. We compared staining patterns with idiopathic PAH (IPAH) and pulmonary veno-occlusive disease (PVOD), as SScPAH vasculopathy differs from IPAH and sometimes displays features of PVOD. Immunoreactivity patterns of phosphorylated PDGFR-ß (pPDGFR-ß) and the ligand PDGF-B were evaluated to provide more insight into the patterns of PDGFR-b activation. METHODS: Lung tissue specimens from five SScPAH, nine IPAH, six PVOD patients and five controls were examined. Immunoreactivity was scored for presence, distribution and intensity. RESULTS: All SScPAH and three of nine IPAH cases (P = 0.03) showed PDGFR-ß-immunoreactivity in small vessels (arterioles/venules); of five SScPAH vs. two of nine IPAH cases (P = 0.02) showed venous immunoreactivity. In small vessels, intensity was stronger in SScPAH vs. IPAH. No differences were found between SScPAH and PVOD. One of five normal controls demonstrated focally mild immunoreactivity. There were no differences in PDGF-ligand and pPDGFR-b-immunoreactivity between patient groups; however, pPDGFR-b-immunoreactivity tended to be more prevalent in SScPAH small vasculature compared to IPAH. Vascular EGFR-immunoreactivity was limited to arterial and arteriolar walls, without differences between groups. No immunoreactivity was observed in vasculature of normals. CONCLUSIONS: PDGFR-ß-immunoreactivity in SScPAH is more common and intense in small- and post-capillary vessels than in IPAH and does not differ from PVOD, fitting in with histomorphological distribution of vasculopathy. PDGFR-ß immunoreactivity pattern is not paralleled by pPDGFR-ß or PDGF-B patterns. PDGFR-ß- and EGFR-immunoreactivity of pulmonary vessels distinguishes PAH patients from controls.

Characteristics of interstitial fibrosis and inflammatory cell infiltration in right ventricles of systemic sclerosis-associated pulmonary arterial hypertension.

Objective. Systemic sclerosis-associated pulmonary arterial hypertension (SScPAH) has a disturbed function of the right ventricle (RV) when compared to idiopathic PAH (IPAH). Systemic sclerosis may also affect the heart. We hypothesize that RV differences may occur at the level of interstitial inflammation and-fibrosis and compared inflammatory cell infiltrate and fibrosis between the RV of SScPAH, IPAH, and healthy controls. Methods. Paraffin-embedded tissue samples of RV and left ventricle (LV) from SScPAH (n = 5) and IPAH (n = 9) patients and controls (n = 4) were picrosirius red stained for detection of interstitial fibrosis, which was quantified semiautomatically. Neutrophilic granulocytes (MPO), macrophages (CD68), and lymphocytes (CD45) were immunohistochemically stained and only interstitial leukocytes were counted. Presence of epi- or endocardial inflammation, and of perivascular or intimal fibrosis of coronary arteries was assessed semiquantitatively (0-3: absent to extensive). Results. RV's of SScPAH showed significantly more inflammatory cells than of IPAH (cells/mm(2), mean ± sd MPO 11 ± 3 versus 6 ± 1; CD68 11 ± 3 versus 6 ± 1; CD45 11 ± 1 versus 5 ± 1 , P < .05) and than of controls. RV interstitial fibrosis was similar in SScPAH and IPAH (4 ± 1 versus 5 ± 1%, P = .9), and did not differ from controls (5 ± 1%, P = .8). In 4 SScPAH and 5 IPAH RV's foci of replacement fibrosis were found. No differences were found on epi- or endocardial inflammation or on perivascular or intimal fibrosis of coronary arteries. Conclusion. SScPAH RVs display denser inflammatory infiltrates than IPAH, while they do not differ with respect to interstitial fibrosis. Whether increased inflammatory status is a contributor to altered RV function in SScPAH warrants further research.