Treatment of pulmonary hypertension

Pulmonary hypertension

Pulmonary hypertension encompasses a range of conditions directly or indirectly leading to elevated pressures within the pulmonary arteries. Five main groups of pulmonary hypertension are recognized, all defined by a mean pulmonary artery pressure of >20 mmHg: pulmonary arterial hypertension (rare), pulmonary hypertension associated with left-sided heart disease (very common), pulmonary hypertension associated with lung disease (common), pulmonary hypertension associated with pulmonary artery obstructions, usually related to thromboembolic disease (rare), and pulmonary hypertension with unclear and/or multifactorial mechanisms (rare). At least 1% of the world's population is affected, with a greater burden more likely in low-income and middle-income countries. Across all its forms, pulmonary hypertension is associated with adverse vascular remodelling with obstruction, stiffening and vasoconstriction of the pulmonary vasculature. Without proactive management this leads to hypertrophy and ultimately failure of the right ventricle, the main cause of death. In older individuals, dyspnoea is the most common symptom. Stepwise investigation precedes definitive diagnosis with right heart catheterization. Medical and surgical treatments are approved for pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension. There are emerging treatments for other forms of pulmonary hypertension; but current therapy primarily targets the underlying cause. There are still major gaps in basic, clinical and translational knowledge; thus, further research, with a focus on vulnerable populations, is needed to better characterize, detect and effectively treat all forms of pulmonary hypertension.

Pulmoner Arteriyel Hipertansiyonlu Hastalarda İnspiratuar Kas Eğitiminin Fonksiyonel Egzersiz Kapasitesi ve Yaşam Kalitesi Üzerine Etkisi: Bir Sistematik Derleme

Pulmoner Arteriyal Hipertansiyon hastalarında, hastalığın erken dönemlerinde semptomlar eforla ortaya çıkarken, hastalığın ileri evrelerinde dinlenme durumunda da gözlenebilir. Pulmoner Arteriyal Hipertansiyon hastaları için optimize edilmiş tıbbi tedavi bulunmasına rağmen, çoğu Pulmoner Arteriyal Hipertansiyon hastası düşük egzersiz kapasitesi ve yaşam kalitesinden şikayetçidir. Pulmoner Arteriyal Hipertansiyon tedavi parametrelerinden biri pulmoner rehabilitasyondur. Pulmoner rehabilitasyon muldisipliner bir yaklaşımdır. Pulmoner Arteriyal Hipertansiyon için en önemli bileşeni fizyoterapi programıdır. Kişiye özel fizyoterapi programları egzersiz eğitimi, solunum kas eğitimi, hasta eğitimi bileşenlerinden oluşmaktadır. Solunum kas kuvveti eğitimi daha çok spesifik olarak İnspiratuar Kas Eğitimi şeklinde uygulanmaktadır. Pulmoner Arteriyal Hipertansiyonlu hastalar için İnspiratuar Kas Eğitimi uygulamasının genel etkilerini araştıran ve konu alan çalışma sayısı azdır. Bu çalışmanın amacı Pulmoner Arteriyal Hipertansiyonlu hastalarda İnspiratuar Kas Eğitimi’nin hastanın fonksiyonel egzersiz kapasitesinin ve yaşam kalitesinin artmasında etkili midir? sorusunu cevaplamaktır. Ocak 2022 tarihinden önce PubMed, Web of Science, Cochrane Library olmak üzere üç ana veri tabanında arama yapıldı. Arama son 5 yılda yayınlanan randomize kontrollü prospektif çalışmalar olacak şekilde sınırlandırıldı. Pulmoner Arteriyal Hipertansiyonlu hastalarda İnspiratuar Kas Eğitimi uygulanan çalışmalar dahil edildi. Tam metinler okunduktan sonra dahil edilme kriterlerine uygun iki çalışma bulundu. Bu yayınların tümü randomize kontrollü prospektif çalışmalardı. Çalışmalar incelendiğinde, Pulmoner Arteriyal Hipertansiyonlu hastalarda İnspiratuar Kas Eğitimi uygulamasının, fonksiyonel egzersiz kapasitesini ve inspiratuar kas kuvvetini arttırdığı ancak yaşam kalitesini arttırmadaki etkinliğinin belirsiz olduğu sonucuna varıldı.

Complications in the adult asplenic patient: A review for the emergency clinician

BACKGROUND

The spleen performs several important physiologic functions. However, patients can have functional asplenia or have their spleen removed for a number of reasons, which can put them at risk for several dangerous complications.

OBJECTIVE

This narrative review provides a focused evaluation of adult asplenic patients and complications in the emergency departing setting.

DISCUSSION

The spleen plays integral roles in the immune and reticuloendothelial systems and also modulates the inflammatory and coagulation cascades. Asplenia refers to the anatomic or physiologic loss of splenic function, which may be due to trauma, immunological, hematological, or oncological etiologies. Asplenic patients are at risk for several complications including infection, arterial and venous thrombosis, and pulmonary hypertension. Fever in an asplenic patient and overwhelming post-splenectomy infection (OPSI) are medical emergencies with a high mortality and require rapid evaluation and management with broad-spectrum antibiotics. Asplenic patients are at increased risk of arterial thrombosis, such as coronary artery disease, and venous thrombosis including deep venous thrombosis, pulmonary embolism, and splenic and portal vein thrombosis. Management of venous thrombosis includes anticoagulation. Pulmonary hypertension with associated right ventricular dysfunction may also occur in asplenia. These patients require hemodynamic stabilization with an emphasis on inciting causes and treatment of the pulmonary hypertension.

CONCLUSIONS

The spleen is an integral organ involved in several physiologic functions. Asplenia, or absence of spleen function, is associated with severe complications. Knowledge of these complications can improve the care of these patients.

Epidemiology and risk factors in CKD patients with pulmonary hypertension: a retrospective study

BACKGROUND

Pulmonary hypertension (PH) is a rare disease often associated with high mortality and is recently recognized as a common complication secondary to chronic kidney disease (CKD). Epidemiological data for this disorder across the spectrum of CKD is poorly understood.

METHODS

We retrospectively analyzed 705 CKD patients with complete clinical records from July 2013 to September 2015. All the patients were estimated by echocardiography and PH was defined as pulmonary artery systolic pressure (PASP) > 35 mmHg. The prevalence of PH in CKD patients was investigated, and their association was evaluated with a logistic regression model.

RESULTS

The overall prevalence of PH was 47.38%, in which mild, moderate and severe PH accounted for 22.13, 15.04 and 10.21%, respectively. The prevalence of PH in CKD stage 1-5 was 14.29, 33.33, 38.89, 40.91 and 64.47%. The prevalence of total PH was 57.63% in PD patients and 58.82% in HD patients. Compared with the non-dialysis patients, the prevalence of PH was much higher in patients receiving dialysis. Body mass index (BMI), hemoglobin, triglyceride (TG), proteinuria, parathyroid hormone (PTH) and estimated glomerular filtration rate (eGFR) were independent risk factors of PH in CKD patients.

CONCLUSIONS

The prevalence of PH is increased with the deterioration of renal function, however, which has no direct relation to the severity of PH. PH occurs more frequently in dialysis patients. Higher BMI and TG, more sever anemia, proteinuria and secondary hyperparathyroidism, poor renal dysfunction predict predict the more prevalence of PH in CKD patients.

Upregulation of Transient Receptor Potential Canonical Channels Contributes to Endotoxin-Induced Pulmonary Arterial Stenosis

Background

Septic shock is a pathologic condition caused by endotoxin-producing bacteria, and often associated with severe pulmonary hypertension. Inflammation is a major systemic response to endotoxin; however, it is unknown whether endotoxin has a direct impact on pulmonary arteries that contributes to pathogenesis of pulmonary hypertension.

Material/Methods

Rat pulmonary arteries and primary pulmonary arterial smooth muscle cells (PASMCs) were cultured in vitro and treated with lipopolysaccharide (LPS) and blockers of transient receptor potential canonical (TRPC) channels. Neointimal growth and arterial stenosis were observed on cryosections of cultured pulmonary arteries. Proliferation of PASMCs was examined by a WST-1 (water-soluble tetrazolium salt) assay. Expression of TRPC genes in pulmonary arteries and PASMCs were detected and quantified by real-time polymerase chain reaction and Western blotting.

Results

LPS significantly induced neointimal growth and stenosis of pulmonary arteries and promoted proliferation of PASMCs. TRPC channel blockers 2-aminoethoxydiphenyl borate and SKF-96365 inhibited LPS-induced remodeling of pulmonary arteries and PASMC proliferation. Expression of TRPC1/3/4/6 was detected in pulmonary arteries and PASMCs. LPS treatment dramatically increased the expression of TRPC3 and TRPC4 at both messenger RNA and protein levels.

Conclusions

LPS stimulates stenosis of pulmonary arteries through enhancement of TRPC-mediated Ca²⁺ entry into PASMCs, which is caused by upregulation of TRPC3 and TRPC4 channels.

Plasma biomarkers of pulmonary hypertension identified by Fourier transform infrared spectroscopy and principal component analysis

The main goal of this study was to find specific plasma spectral markers associated with pulmonary arterial hypertension (PAH) induced by monocrotaline injection in rats. FTIR was used to monitor biochemical changes in plasma caused by PAH as compared with the systemic hypertension induced by partial ligation on the left artery and with the control group. Both pathologies, systemic and pulmonary hypertension, induced a unique response in the biochemical content of plasma, mainly related to the composition and secondary structure of plasma proteins. For PAH, β-pleated sheet components of plasma proteins were identified whereas the protein composition in systemic hypertension was dominated by unordered structures. In addition, a higher concentration of tyrosine-rich proteins was found in plasma in PAH than in systemic hypertension. The differences between both pathologies were identified also in terms of lipid composition/metabolism as well as in the content of RNA and glucose, suggesting that lipid peroxidation appears upon pulmonary hypertension development. In summary, this work demonstrates that FTIR spectroscopy supported by principal component analysis (PCA) has the potential to become a fast and non-destructive method for biochemical characterization of plasma that consequently could have a diagnostic significance in pulmonary hypertension.

Mesenchymal stem cells suppress CaN/NFAT expression in the pulmonary arteries of rats with pulmonary hypertension

Inflammation and hyperproliferation of pulmonary artery smooth muscle cells (PASMCs) is considered the primary pathological feature of pulmonary hypertension (PH). The present study determined that mesenchymal stem cells (MSCs) suppress the expression of calcineurin (CaN) and nuclear factor of activated T-cells (NFAT) in the pulmonary arteries of rats, and this may exert a therapeutic effect on PH. The potential therapeutic effects of MSCs on PH were assessed via the transplantation of human umbilical cord-derived MSCs, which were cultured in serum-free medium, into a monocrotaline (MCT)-induced PH rat model. Subsequently, the expression levels of tumor necrosis factor (TNF)-α in lung tissue and plasma, and of CaN and NFATc2 in pulmonary arteries were assessed. In the rat model of MCT-induced PH, investigated in the present study, TNF-α expression levels were detected in the lung tissue, and the levels of TNF-α in the plasma were increased. Furthermore, in addition to hemodynamic changes and the evident medial hypertrophy of the pulmonary muscular arterioles, CaN and NFATc2 expression levels were significantly upregulated in the pulmonary arteries. In the present study, the transplantation of MSCs, cultured in serum-free medium, decreased the levels of TNF-α in the lung tissue and plasma of rats, and downregulated CaN and NFATc2 expression in the pulmonary arteries. Furthermore, hemodynamic abnormalities and medial hypertrophy of the pulmonary muscular arterioles were notably improved. Therefore, the results of the present study may suggest that the administration of MSCs in PH may suppress the production of TNF-α, and downregulate the expression of CaN and NFATc2 in pulmonary arteries, which may provide an effective treatment for PH by suppressing the pathological proliferation of PASMCs.

The incidence and severity of pulmonary hypertension in obstructive sleep apnea with hypothyroidism

BACKGROUND

Hypothyroidism and obstructive sleep apnea (OSA) are both common health problems and can be seen together. Each of these 2 diseases can cause pulmonary hypertension (PH). We aimed to determine whether hypothyroidism with OSA has a significant effect on the frequency and severity of PH.

MATERIAL AND METHODS

A total of 236 patients were included in the study. Patients were divided into 3 groups: Group I, Obstructive Sleep Apnea (n=149); Group II, Hypothyroidism (n=56); and Group III, Obstructive Sleep Apnea-Hypothyroidism (n=31). All patients underwent polysomnography and echocardiography and serum levels of thyroid-stimulating hormone (TSH) and free thyroxine 4 (FT4) were analyzed.

RESULTS

There were 167 male and 69 female participants, and the mean age was 47.8 ± 11.5 (Group I: 81.9% male, 18.1% female; Group II: 44.6% male, 55.4% female; Group III: 64.6% male, 35.4% female). Distribution of mean pulmonary arterial pressure on echocardiography was statistically different among the 3 groups (x(2)=14.99, p=0.006). When adjusted according to the apnea-hypopnea index (AHI), age, and body mass index (BMI), a significant relation with PH was determined (p=0.002).

CONCLUSIONS

The combination of hypothyroidism with OSA is associated with an increased frequency and severity of PH. When PH is found out of line with the severity of OSA, thyroid dysfunction should be investigated.

Promising therapeutic effects of sodium tanshinone IIA sulfonate towards pulmonary arterial hypertension in patients

BACKGROUND

Pulmonary hypertension (PH) is a lethal disease with no cure currently available. Sodium Tanshinone IIA sulfonate (STS) is a water-soluble derivative of tanshinone IIA isolated as the major active component from salvia miltiorrhiza, a kind of Chinese herbal medicine. We investigate the efficacy of STS towards treatment of PH patients.

METHODS AND RESULTS

Five hospitalized patients were randomly enrolled for this study. These patients were suffering from various types of serious PH without getting sufficient benefits from sildenafil treatment (20 mg tid) for at least three months. The efficacy of STS on PH was evaluated by measuring the pulmonary arterial systolic pressure (PASP), RV size by echocardiography, 6-minute walking distance (6MWD), Borg dyspnea score, and WHO functional class of PH. Patients aged from 17 to 46 (average 33±11) years old, pulmonary arterial systolic pressure (PASP) ranged from 60 to 140 mmHg, RV size ranged from 25 to 39 mm were included in study. At the endpoint of observation for 8 weeks of STS infusion, they obtained reduction of PASP in the range of 14-45 (average 28.6±12.5) mmHg, RV size in the range of 0-10 (average 4.2±1.6). All patients exhibited improved exercise capacity with an increase of 6MWD from 63 to 268 (average 138.4±40.7) meters, significantly reduced Borg dyspnea score from maximum 9 down to 1 or 0, and reduced WHO functional class of PH from III or IV down to II.

CONCLUSIONS

These results indicate that STS exhibits remarkable beneficiary effects on treating PH patients either alone or in concert with sildenafil.