Mean Pulmonary Artery Pressure Levels Research Articles

Prognostic Significance of the N-Terminal Pro-B-Type Natriuretic Peptide in Lung Transplant Candidates on the Waiting List.

We investigated the prognostic significance of N-terminal pro-B-type natriuretic peptide (NT-proBNP) in lung transplant candidates, in a retrospective single-center study. Data regarding various baseline characteristics and all-cause mortality were collected for 205 lung transplant candidates placed on waitlist for transplantation from November 2017 to December 2019. Associations of NT-proBNP levels with baseline characteristics and mortality were analyzed. Results showed NT-proBNP values correlated positively with age, forced vital capacity, mean pulmonary artery pressure (MPAP), and pulmonary capillary wedge pressure; and negatively with diffusing lung capacity for carbon monoxide and cardiac index. The optimal cut-off of NT-proBNP for predicting MPAP levels > 35 mmHg was 251 pg/mL; with 58.1% sensitivity, 85.7% specificity, 45.0% positive predictive value, and 91.0% negative predictive value. During a median follow-up period of 2.2 years, 97 patients underwent lung transplantation, 42 died waiting for donation, and 66 were alive and still waiting for transplantations. On multivariate analysis, higher NT-proBNP levels were strongly associated with increased mortality among waitlisted lung transplant candidates (HR 1.49, 95% CI 1.10–2.03, p = 0.01). In conclusion NT-proBNP can predict mortality among waitlisted lung transplant candidates. Lower levels of NT-proBNP can preclude severe pulmonary artery hypertension. Assessment of NT-proBNP may improve risk stratification among lung transplant candidates.

ГЕМОДИНАМИКА МАЛОГО КРУГА КРОВООБРАЩЕНИЯ У МУЖЧИН МОЛОДОГО И СРЕДНЕГО ВОЗРАСТА С ОСТРЫМ ПОВРЕЖДЕНИЕМ ПОЧЕК ПРИ ИНФАРКТЕ МИОКАРДА

Relevance. Hemodynamics changes of the pulmonary circulation in myocardial infarction complicated by acute kidney injury are not well understood. Aim. To evaluate the characteristics of pulmonary circulation in men under 60 years old with acute kidney injury in myocardial infarction to improve prevention and outcomes. Material and methods. The study included men 19-60 years old with type I myocardial infarction. The patients were divided into two age-comparable groups: I - study group, with acute kidney injury - 25 patients; II - control, without it - 486 patients. A comparative analysis of pulmonary circulation parameters in the first 48 hours (1) and at the end of the third week of the disease (2), their dynamics, analysis of the risks of developing acute kidney damage and chronic heart failure in the selected groups were performed. Results. The study group differed in a lower heart rate (HR1) (66.3±12.2 from the control group (75.8±18.8; p=0.003). It showed a tendency towards lower the mean pulmonary artery pressure (MPAP) and total pulmonary resistance (TPR) at both points of the study. In both groups, there was a similar dynamic of decrease in the MPAP and TPR levels, more pronounced in the control group (MPAPII: -14.3%; MPAPI: -6.1 %; TPRII: -29.9%; TPRI: -21.8%; p<0.0001) and multidirectional - for HR: in the study group, an increase in HR was noted by 0.9% (p<0.0001), and in the control - its decrease by 8.4% (p<0.0001). Risk markers of the acute kidney injury developing were MPAP1˂30.4 mm Hg, HR1˂67 per minute and TPR1˂622.8 dyne•s•cm-5, the presence of chronic heart failure and cardiac asthma among the disease complication. The predictors of chronic heart failure in the study group were MPAP1≥26.9 mm Hg and HR1≥62 min. Conclusions. In case of acute kidney injury, lower levels of pulmonary circulation indicators are noted, their lower dynamics during the observation period, and a greater frequency of observation of chronic heart failure in comparison with the control group. The above listed values of the pulmonary circulation parameters have been assessed as a risk marker of the acute kidney injury and chronic heart failure development.

THE PULMONARY CIRCULATION PECULIARITIES IN MEN UNDER 60 YEARS OLD WITH PULMONARY HYPERTENSION, DEVELOPED DURING MYOCARDIAL INFARCTION

Relevance. Formation of pulmonary hypertension (PH) in myocardial infarction (MI) remains poorly understood. Aim. To evaluate changes in pulmonary circulation indicators (PCI) in men under 60 years old (y.o) with PH that is developing in subacute MI period to improve understanding of developmental options and prevention. Material and methods. The study included men aged 19-60 y.o. with MI and various dynamics of mean pulmonary ar-tery pressure (MPAP), determined by echocardiography (A. Kitabatake) in the first 48 hours (1) and completion of third week (2) of MI. Patients were divided into four groups: studied (I) included 84 patients (mean age 50.4±7.1 y.o) with PH (MPAP2 25 and more mm Hg) and normal level of MPAP1. Group II included patients with a normal level of MPAP in both phases of the study (88 men, 52.1±6.6 y.o); group III – with elevated levels of MPAP at both points of study (184 men, 51.2±5.5 y.o) and IV – with increased levels of MPAP1 and normal levels of MPAP2 (94 men, 50.5±6.8 y.o). A comparative assessment of PCI in selected groups was performed. Results. In first 48 hours of MI, the minimum values of MPAP (I: 21.9±3.3; II: 20.3±2.5; III: 39.0±11.2 (mm Hg)) and total pulmonary resistance (TPR) ) (I: 380.0±171.0; II: 306.8±136.3; III: 616.0±279.8 (dyn×sec×cm-5)) were noted in group II, and the maximum - in III (p˂0.0001). When considering their dynamics at the end of the third week of MI, MPAP increased in I (39.5%; p˂0.0001), decreased in III (16.0%; p˂0.0001) and IV groups (42.9%; p˂0.0001). TPR decreased in II (12.1%), III (28.6%) and IV (54.2%) groups (p ˂0.0001). Conclusions. The study group is distinguished by unfavorable changes in PCI during observation period, in contrast to other groups, which confirms expediency of assessing dynamics of these parameters as possible marker of negative prognosis for PH.

Right ventricle performances with echocardiography and 99mTc myocardial perfusion imaging in pulmonary arterial hypertension patients.

Right heart catheterization is commonly used to measure right ventricle hemodynamic parameters and is the gold standard for pulmonary arterial hypertension diagnosis; however, it is not suitable for patients' long-term follow-up. Non-invasive echocardiography and nuclear medicine have been applied to measure right ventricle anatomy and function, but the guidelines for the usefulness of clinical parameters remain to be established. The goal of this study is to identify reliable clinical parameters of right ventricle function in pulmonary arterial hypertension patients and analyze the relationship of these clinical parameters with the disease severity of pulmonary arterial hypertension. In this study, 23 normal subjects and 23 pulmonary arterial hypertension patients were recruited from January 2015 to March 2016. Pulmonary arterial hypertension patients were classified into moderate and severe pulmonary arterial hypertension groups according to their mean pulmonary arterial pressure levels. All the subjects were subjected to physical examination, chest X-ray, 12-lead electrocardiogram, right heart catheterization, two-dimensional echocardiography, and technetium 99m (99mTc) myocardial perfusion imaging. Compared to normal subjects, the right heart catheterization indexes including right ventricle systolic pressure, right ventricle end diastolic pressure, pulmonary artery systolic pressure, pulmonary artery diastolic pressure, pulmonary vascular resistance, and right ventricle end systolic pressure increased in pulmonary arterial hypertension patients and were correlated with mean pulmonary arterial pressure levels. Echocardiography parameters, including tricuspid regurgitation peak velocity, tricuspid regurgitation pressure gradient, tricuspid annular plane systolic excursion and fractional area, right ventricle-myocardial performance index, were significantly associated with the mean pulmonary arterial pressure levels in pulmonary arterial hypertension patients. Furthermore, myocardial perfusion imaging was not observed in the normal subjects but in pulmonary arterial hypertension patients, especially severe pulmonary arterial hypertension subgroup, and showed potential diagnostic properties for pulmonary arterial hypertension. In conclusion, mean pulmonary arterial pressure levels are correlated with several right heart catheterization and echocardiography markers in pulmonary arterial hypertension patients; echocardiography and 99mTc myocardial perfusion can be used to evaluate right ventricle performance in pulmonary arterial hypertension patients. Impact statement In this study, we analyzed the clinical parameters for evaluating RV function, including right ventricle catheterization (RHC), echocardiography, and technetium 99m (99mTc) myocardial perfusion imaging (MPI) in normal Asian subjects and PAH patients ( n = 23 for each group). Our results demonstrated that six RHC indexes, four echocardiography indexes and MPI index were significantly altered in PAH patients and correlated with the levels of mean pulmonary arterial pressure. Importantly, we evaluated the diagnostic performance of MPI and found that MPI has a strong diagnostic accuracy in PAH patients. The findings from this study will be of interest to clinical investigators who make diagnosis and therapeutic strategies for PAH patients.

Pulmonary Artery Pressure and Benefit of Lung Transplantation in Adult Cystic Fibrosis Patients

The effect of lung transplantation (LTx) in patients afflicted with cystic fibrosis (CF) and pulmonary hypertension (PH) at placement on the waiting list is not well studied. To predict the relationship between initial mean pulmonary artery pressure (MPAP) and hazard ratio (HR) of death after listing associated with LTx in adult patients with CF, the United Network for Organ Sharing database was queried for the years 2005 to 2013. Survival was assessed from waiting list entry until death on the waiting list, death after LTx, or censoring. A multivariate Cox model was performed to estimate the HR of LTx conditional on MPAP at listing. Of 1,841 patients with CF, 10% (177) died on the waiting list, 18% (325) were censored without undergoing LTx, and 73% (1,339) underwent transplantation, 361 of whom died after transplantation. A multivariate Cox model of survival since list entry including 1,336 patients found a protective but statistically insignificant benefit of LTx for patients whose MPAP at listing was 25 mm Hg (HR, 0.879; 95% confidence interval [CI], 0.657-1.177; p = 0.388), yet LTx was predicted to be more protective at higher initial MPAP levels, as indicated by the significant interaction term between LTx and MPAP (HR, 0.953; 95% CI, 0.928-0.978; p < 0.001). The predicted LTx HR and 95% CI were protective (HR < 1) at p < 0.05 for patients with MPAP greater than or equal to 30 mm Hg at listing. Survival benefit of LTx in CF was increasingly protective at higher MPAP levels, with a severity level of PH established above which a survival advantage of LTx was found.

Do pre-adenotonsillectomy echocardiographic findings change postoperatively in children with severe adenotonsillar hypertrophy

Purpose Hypertrophy of adenotonsillar tissue is one of the most common problems in childhood age and causes upper airway obstruction and even obstructive sleep apnea symptoms in severe forms. The aim of this study is to evaluate the changes of pre-adentonsillectomy echocardiographic findings after operation. Material and methods From August 2007 to November 2008, 55 children with adenotonsillar hypertrophy and obstructive-sleep symptoms (aged 3–11 years old of which 35 were males and 20 females) were randomly selected. Preoperatively echocardiography was performed for all patients by the pediatric cardiologist. In control group 55 children who referred to otolaryngology clinic because of non adenotonsillar related disease evaluated. One month and six months after operation, patients with positive findings were followed up and again echocardiography was performed separately. Results No complaints of apnea were reported. Tonsillar grades of all cases were type III or IV. The preoperative mean pulmonary arterial pressure levels of the 4 (7.3%) children were higher than normal range (25 mm Hg) and it decreased significantly after operation ( P < 0.000) (Preoperative MPAP = 32 ± 3 mm Hg, and six months postoperative follow up, MPAP = 11 ± 5 mm Hg). All the patients’ parents complained about severe open mouth snoring, agitated sleep and hyperpnoea of their children. The preoperative tricuspid regurgitation pressure level of 7 children was higher than normal range and it decreased significantly after operation ( P < 0.000 preoperative TR = 34 ± 8 mm Hg postoperative TR = 19 ± 6 mm Hg). AC/ET in these seven patients were lower than 0.4. In control group echocardiography findings are normal. Conclusion Severe chronic hypertrophic adenotonsillar tissue caused higher tricuspid regurgitation pressure and mean pulmonary arterial pressure.

Patent Foramen Ovale among Patients with Mild Chronic Obstructive Pulmonary Disease and Unexplained Hypoxia

To evaluate whether patent foramen ovale (PFO) is a contributing factor to hypoxia in patients with chronic obstructive pulmonary disease (COPD). Twenty-one patients over 40 years of age with mild COPD (Forced expiratory volume (FEV1)/Forced Vital Capacity (FVC): > 50%) who had hypoxia (PO(2) < 80 mmHg, SaO(2) < 95%) that could not be explained by COPD alone were included in this study. Arterial oxygen pressures (PO(2)) and arterial oxygen saturations (SaO(2)) were recorded from laboratory evaluations of arterial blood gases. Respiratory function tests were performed to analyze the degree of COPD. Standard and contrast echocardiography was used to calculate pulmonary artery pressure (PAP) levels and to determine patients with a PFO. The mean age of the patients was 64 +/- 12 years. Four patients (19%) had a PFO. The mean PO(2), mean SaO(2), and mean PAP levels were 57.4 +/- 6.8 mmHg, 90 +/- 3.2%, and 33.8 +/- 5.4 mmHg, respectively, in patients without PFO. The mean PO(2), mean SaO(2), and mean PAP levels were 46.5 +/- 13.7 mmHg, 79.3 +/- 12.8%, and 42.5 +/- 6.5 mmHg, respectively, in patients with PFO. There were no statistically significant differences noted between the two groups in the PO(2) levels (P = 0.172) and SaO(2) levels (P = 0.065). A comparison of the PAP levels revealed a statistically significant difference between the two groups, with values that were more elevated in the PFO group than in the non-PFO group (P = 0.031). This study demonstrated that PFO is not a contributing factor to deep hypoxia in COPD patients with lower PO(2) and SaO(2) levels; however, higher PAP levels were detected in patients with a PFO. Further studies involving a larger number of patients are needed to be conclusive.

The effects of tonsillectomy and adenoidectomy on pulmonary arterial pressure in children

Purpose It is well known that hypertrophic tonsils and adenoids may cause upper-airway obstruction. The aim of this study is to determine the mean pulmonary arterial pressure (mPAP) in children with hypertrophic tonsils and adenoids and to clarify whether tonsillectomy and adenoidectomy (T&A) has any effect on mean pulmonary arterial pressure of these children. Materials and methods Fifty-two randomly selected children (36 male, 16 female) aged between 4 and 11 (mean 7.7 ± 2.5) a with a diagnosis of upper-airway obstruction resulting from hypertrophied tonsils and adenoids were included in our study. Thirty-three children were assigned as controls with similar age and sex distrubution with the study groups. Mean pulmonary arterial pressure was measured by using Doppler echocardiography preoperatively and mean 5.4 ± 2.9 months postoperatively in all subjects. Results When the mean pulmonary arterial pressure values of study and control group compared preoperatively, the mean pulmonary arterial pressure levels of the children in the study group were significantly higher than the mean pulmonary arterial pressure levels of the children in the control group ( P < .05) (study group mean PAP = 23.13 ± 7.68, control group mean PAP = 16.11 ± 7.24) (Levene’s test, P < .05). When the preoperative and postoperative results were compared, it was found that there was a statistically significant decrease in mean pulmonary arterial pressures in these 52 children (preoperative mean PAP = 23.13 ± 7.68, postoperative mean PAP = 17.00 ± 6.99) (paired sample t test, P < .05). Twenty-seven of the 52 subjects in the study group were pulmonary hypertensive preoperatively. mPAPs of 18 of these children decreased to normal range yielding 9 subjects, and this was also found ststistically significant (McNemar test, P < .001). Conclusion This study showed that obstructive adenoid and tonsillar hypertrophy causes higher mPAP values in children and revealed that T&A is an effective therapeutic measure in such patients.

Relationship between ECG findings and pulmonary artery pressure in patients with acute massive pulmonary thromboembolism.

Pulmonary thromboembolism (PTE) is associated with various electrocardiogram (ECG) abnormalities, but the utility of evaluating the severity of PTE based on ECG abnormalities alone has not been investigated in Japanese patients previously. The purpose of this study was to examine the relationship between ECG abnormalities and the mean pulmonary artery pressure (MPAP) in patients with acute massive PTE (AMPTE). ECG examination of 21 patients, who were diagnosed with AMPTE by pulmonary arteriography, found that S(1)Q(3)T (3) was the most frequently observed abnormality (in 67% of the patients), followed by negative T (62%), clockwise rotation (57%), and ST elevation (48%). When these patients were divided into 2 groups based on the level of MPAP, 8 of the 11 ECG findings, which were associated with PTE in a previous report, were more frequently observed in Group H (MPAP >/=40 mmHg) than in Group L (MPAP <40 mmHg). MPAP correlated significantly with the total number of ECG abnormalities (r=0.82, p<0.001). In particular, at least 5 ECG abnormalities were noted in patients with MPAP >/=45 mmHg. These results suggested that the total number of ECG abnormalities in patients with AMPTE can be used to evaluate the severity of APTE, including PAP level.

Non-Invasive Estimation of Pulmonary Arterial Hypertension in Chronic Obstructive Pulmonary Disease

The feasibility and reliability of the combination of several noninvasive methods using a multivariate method of analysis to predict pulmonary artery hypertension (PAH) is evaluated in 20 patients with chronic obstructive pulmonary disease. These methods comprised arterial blood gases (Pao2, Paco2), pulmonary functional parameters (FEV1), echo-Doppler parameters (tricuspid regurgitation jets, acceleration time on pulmonary valve), computed tomography measurements (transhilar distance, hilar thoracic index, and measurement of the descending branch of the right pulmonary artery to the lower lobe). A multiple stepwise regression analysis (including one Doppler parameter, two parameters of arterial blood gases, and one functional parameter) revealed a coefficient of determination (R2) equal to 0.954 for mean pulmonary artery pressure (MPAP) with a standard error of estimate (S.E.E.) of 5.25 mmHg. A stepwise regression analysis including computed tomography and radiographic parameters revealed an R2 equal to 0.970 for PAP with a S.E.E. of 4.26 mmHg. Logistical regression analysis classified correctly 80% of patients with PAH using noninvasive methods such as the diameter of the main pulmonary artery and the diameter of the left pulmonary arterial branch calculated by computed tomography. Not only the presence of PAH but also the level of MPAP can be estimated by the combination of multiple stepwise and logistical regression analyses.

Dimethylthiourea ameliorates acute lung injury induced by phorbol myristate acetate in dogs.

The protective effects of dimethylthiourea, a potent scavenger of hydroxy radical (.OH) and hydrogen peroxide, in experimental lung injury in large animals remain controversial. The present study was designed to determine whether dimethylthiourea can ameliorate the acute lung injury produced in dogs by phorbol myristate acetate. Six dogs were infused with dimethylthiourea (0.75 g/kg in saline) for 1.5 hrs, beginning 1 hr before an i.v. bolus injection of phorbol myristate acetate (17 micrograms/kg); six dogs received phorbol myristate acetate (17 micrograms/kg) alone; and six dogs were infused with saline alone. Hemodynamic changes, arterial oxygenation, and the development of lung edema were monitored for 4 hrs after phorbol myristate acetate injection to assess the extent of lung damage. As compared with the dogs that received phorbol myristate acetate alone, the edematous lung damage was significantly reduced in those dogs that received dimethylthiourea as well as phorbol myristate acetate. In the dimethylthiourea-treated dogs, the lung wet/dry weight ratios were smaller (p less than .01); protein concentrations in lung lavage fluid were lower (p less than .01); the decrease in PaO2 was significantly reduced (p less than .01); and there were significant reductions in the alveolar-arterial oxygen tension difference (P[A-a]O2) (p less than .01) and shunt (Qsp/Qt) (p less than .05). Also, dimethylthiourea significantly lowered the increased mean pulmonary arterial pressure levels during the second half of the experiment. These experimental data suggest that dimethylthiourea is capable of reducing the neutrophil-mediated lung injury produced by the release of hydroxy radical and/or hydrogen peroxide in dogs exposed to phorbol myristate acetate.