Relationship between Pulmonary Artery Stiffness and Functional Capacity in Patients with Heart Failure with Reduced Ejection Fraction

The effects of sodium-glucose cotransporter 2 inhibitors on the 'forgotten' right ventricle

With the progress in diagnosis, treatment and imaging techniques, there is a growing recognition that impaired right ventricular (RV) function profoundly affects the prognosis of patients with heart failure (HF), irrespective of their left ventricular ejection fraction (LVEF). In addition, right HF (RHF) is a common complication associated with various diseases, including congenital heart disease, myocardial infarction (MI), pulmonary arterial hypertension (PAH) and dilated cardiomyopathy (DCM), and it can manifest at any time after left ventricular assist devices (LVADs). The sodium-glucose cotransporter 2 (SGLT2) inhibition by gliflozins has emerged as a cornerstone medicine for managing type 2 diabetes mellitus (T2DM) and HF, with an increasing focus on its potential to enhance RV function. In this review, we aim to present an updated perspective on the pleiotropic effects of gliflozins on the right ventricle and offer insights into the underlying mechanisms. We can ascertain their advantageous impact on the right ventricle by discussing the evidence obtained in animal models and monumental clinical trials. In light of the pathophysiological changes in RHF, we attempt to elucidate crucial mechanisms regarding their beneficial effects, including alleviation of RV overload, reduction of hyperinsulinaemia and inflammatory responses, regulation of nutrient signalling pathways and cellular energy metabolism, inhibition of oxidative stress and myocardial fibrosis, and maintenance of ion balance. Finally, this drug class's potential application and benefits in various clinical settings are described, along with a prospective outlook on future clinical practice and research directions.

Noninvasive evaluation of pulmonary artery stiffness in heart failure patients via cardiovascular magnetic resonance

Heart failure (HF) presents manifestations in both cardiac and vascular abnormalities. Pulmonary hypertension (PH) is prevalent in up 50% of HF patients. While pulmonary arterial hypertension (PAH) is closely associated with pulmonary artery (PA) stiffness, the association of HF caused, post-capillary PH and PA stiffness is unknown. We aimed to assess and compare PA stiffness and blood flow hemodynamics noninvasively across HF entities and control subjects without HF using CMR. We analyzed data of a prospectively conducted study with 74 adults, including 55 patients with HF across the spectrum (20 HF with preserved ejection fraction [HFpEF], 18 HF with mildly-reduced ejection fraction [HFmrEF] and 17 HF with reduced ejection fraction [HFrEF]) as well as 19 control subjects without HF. PA stiffness was defined as reduced vascular compliance, indicated primarily by the relative area change (RAC), altered flow hemodynamics were detected by increased flow velocities, mainly by pulse wave velocity (PWV). Correlations between the variables were explored using correlation and linear regression analysis. PA stiffness was significantly increased in HF patients compared to controls (RAC 30.92 ± 8.47 vs. 50.08 ± 9.08%, p < 0.001). PA blood flow parameters were significantly altered in HF patients (PWV 3.03 ± 0.53 vs. 2.11 ± 0.48, p < 0.001). These results were consistent in all three HF groups (HFrEF, HFmrEF and HFpEF) compared to the control group. Furthermore, PA stiffness was associated with higher NT-proBNP levels and a reduced functional status. PA stiffness can be assessed non-invasively by CMR. PA stiffness is increased in HFrEF, HFmrEF and HFpEF patients when compared to control subjects.Trial registration The study was registered at the German Clinical Trials Register (DRKS, registration number: DRKS00015615).

In-silico enhanced animal study of pulmonary artery pressure sensors: assessing hemodynamics using computational fluid dynamics

To assess whether in-silico models can be used to predict the risk of thrombus formation in pulmonary artery pressure sensors (PAPS), a chronic animal study using pigs was conducted. Computed tomography (CT) data was acquired before and immediately after implantation, as well as one and three months after the implantation. Devices were implanted into 10 pigs, each one in the left and right pulmonary artery (PA), to reduce the required number of animal experiments. The implantation procedure aimed at facilitating optimal and non-optimal positioning of the devices to increase chances of thrombus formation. Eight devices were positioned non-optimally. Three devices were positioned in the main PA instead of the left and right PA. Pre-interventional PA geometries were reconstructed from the respective CT images, and the devices were virtually implanted at the exact sites and orientations indicated by the follow-up CT after one month. Transient intra-arterial hemodynamics were calculated using computational fluid dynamics. Volume flow rates were modelled specifically matching the animals body weights. Wall shear stresses (WSS) and oscillatory shear indices (OSI) before and after device implantation were compared. Simulations revealed no relevant changes in any investigated hemodynamic parameters due to device implantation. Even in cases, where devices were implanted in a non-optimal manner, no marked differences in hemodynamic parameters compared to devices implanted in an optimal position were found. Before implantation time and surface-averaged WSS was 2.35 ± 0.47  Pa, whereas OSI was 0.08 ± 0.17 , respectively. Areas affected by low WSS magnitudes were 2.5 ± 2.7  cm2 , whereas the areas affected by high OSI were 18.1 ± 6.3  cm2 . After device implantation, WSS and OSI were 2.45 ± 0.49  Pa and 0.08 ± 0.16 , respectively. Surface areas affected by low WSS and high OSI were 2.9 ± 2.7  cm2 , and 18.4 ± 6.1  cm2 , respectively. This in-silico study indicates that no clinically relevant differences in intra-arterial hemodynamics are occurring after device implantation, even at non-optimal positioning of the sensor. Simultaneously, no embolic events were observed, suggesting that the risk for thrombus formation after device implantation is low and independent of the sensor position.

Evaluation of pulmonary artery stiffness and right ventricle functions in polycythemia vera patients by transthoracic echocardiography

INTRODUCTION

Polycythemia vera (PV) is known to be a subgroup of chronic myeloproliferative neoplasms and is recognized as a cause of pulmonary hypertension (PH). Pulmonary artery stiffness (PAS) is a relatively new noninvasive echocardiographic index developed to evaluate the structural features and functions of the pulmonary vascular bed. In this study, we aimed to evaluate right ventricular (RV) functions and PAS in PV patients and healthy controls.

METHODS

A group of 65 consecutive PV patients and 40 healthy controls were included in the study. RV global longitudinal strain (RVGLS) and RV free wall longitudinal strain were (RVFwLS) evaluated using two-dimensional (2D) strain echocardiography. RV volume, systolic and diastolic functions were evaluated with three-dimensional (3D) echocardiography. PAS was calculated using the maximum frequency shift (MFS) and acceleration time of the pulmonary artery flow trace.

RESULTS

PAS values were significantly higher in the PV group than in the control group (25.2 ± 5.2 vs. 18.2 ± 4.2, p < .001). We found that tricuspid annular plane systolic excursion (TAPSE) (p < .001), RV fractional area change (p < .001) and RV ejection fraction (p < .001) measurements evaluated by 3D echocardiography were significantly lower in the PV group.

CONCLUSION

In our study, PAS values were higher in PV patients than in the healthy control group. Patients with PV may have subclinical RV dysfunction, and PAS value can be used in the early diagnosis of PH and RV dysfunction in this patient group.

Assessment of pulmonary arterial stiffness in patients with systemic sclerosis without overt pulmonary hypertension

Pulmonary hypertension (PH) is a pathophysiological disorder that may involve multiple clinical conditions and complicate most systemic diseases. Systemic sclerosis (SSc), represents the leading cause of connective tissue disease (CTD) associated with PAH. Although SSc is a rare disease, it is associated with higher morbidity and early mortality than other rheumatological diseases due to developing SSc-associated interstitial pulmonary disease (ILD) and/or pulmonary arterial hypertension (PAH). The impact of the early diagnosis on the prognosis is evident. In this context, in our study, we aimed to investigate the early changes in pulmonary vascular bed by measuring pulmonary arterial stiffness (PAS) in SSc patients without overt PAH. Sixty-two SSc patients and fifty-eight gender and age-matched, healthy subjects enrolled in this cross-sectional observational study. SSc patients were evaluated in terms of disease duration and severity. Modified rodnan skin score (mRSS) was calculated as disease severity index. Echocardiographic parameters were assessed and compared to the control group. Right ventricular (RV) diameters, systolic pulmonary artery pressure (sPAP), and right ventricle myocardial performance index (RV-MPI) were significantly higher in the SSc group compared to the control group (p < 0.05). Tricuspid annular plane systolic excursion (TAPSE) and right ventricular fractional area change (RVFAC) were significantly lower in the SSc group compared to the control group (p < 0.05). PAS value (25.5 ± 9.2 kHz/ms vs. 18.1 ± 7.4 kHz/ms, p < 0.001) was significantly higher in the SSc group than in the control group. A statistically significant positive correlation relationship was detected between the PAS value and CRP, ESR, disease duration, mRSS. According to these results, in SSc patients, PAS as an inexpensive and easily applicable echocardiographic method might serve as a marker of early detection of PAH.

Effects of Sodium-Glucose Co-Transporter-2 Inhibition on Pulmonary Arterial Stiffness and Right Ventricular Function in Heart Failure with Reduced Ejection Fraction

Background and Objectives: In addition to left ventricular (LV) functions, right ventricular (RV) functions and pulmonary arterial stiffness (PAS) may be adversely affected in patients with heart failure with reduced ejection fraction (HFrEF). Sodium-glucose co-transporter-2 (SGLT2) inhibitor therapy positively affects LV functions as well as having functional and symptomatic benefits in HFrEF patients. In this study, we aimed to evaluate the effects of SGLT2 inhibitor treatment on RV function and PAS in HFrEF patients. Materials andMethods: 168 HFrEF patients with New York Heart Association (NYHA) class ≥2 symptoms despite optimal medical treatment and who were started on SGLT2 inhibitor therapy were included in this retrospective study. NYHA classification, N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels, Minnesota Living with Heart Failure Questionnaire (MLWHFQ) scores, laboratory tests, and transthoracic echocardiography (TTE) measurements were recorded before treatment and at the end of the 6-month follow-up. Results: The mean age of the patients was 62.7 ± 11.4 years, and 38 (22.6%) were women. RV function (RV fractional area change (FAC) (33.8 ± 6.4% vs. 39.2 ± 7.3%, p < 0.001); tricuspid annular plane systolic excursion (TAPSE) (18.4 ± 3.8 mm vs. 19.6 ± 3.6 mm, p < 0.001); RV S’ (10 (8 − 13) cm/s vs. 13 (10 − 16) cm/s, p < 0.001); RV myocardial performance index (RV MPI) (0.68 ± 0.12 vs. 0.59 ± 0.11, p < 0.001); mean pulmonary artery pressure (mPAP) (39.6 ± 7.8 mmHg vs. 32 ± 6.8 mmHg, p = 0.003)) and PAS (24.2 ± 4.6 kHz/ms vs. 18.6 ± 3.1 kHz/ms, p < 0.001) values at the 6-month follow-up after SGLT2 inhibitor therapy significantly improved. It was found that SGLT2 inhibitor treatment provided significant improvement in NYHA classification, MLWHFQ scores, and NT-proBNP levels (2876 ± 401 vs. 1034 ± 361, p < 0.001), and these functional and symptomatic positive changes in HFrEF patients were significantly correlated with positive changes in LVEF, PAS, and RV functional status. Conclusions: SGLT2 inhibitor treatment results in symptomatic and functional well-being in HFrEF patients, as well as positive changes in RV function and PAS.

Feasibility of echocardiographic estimation of Pulmonary Artery Stiffness in horses

Pulmonary artery stiffness (PAS) is an index of pulmonary artery elasticity that permits to evaluate the pulmonary vascular bed in humans. It can early detect an increase in pulmonary artery stiffness as a consequence of remodeling of the vessel wall caused by chronic pulmonary and congenital heart diseases. This remodeling can occur also in horses with chronic respiratory diseases. Thus, PAS could be a useful echocardiographic parameter also in horses. However, in literature, there are no studies regarding PAS in horses. The aim of this study is to evaluate the feasibility of PAS in horses. Fifteen healthy horses were included in this prospective study. Maximal frequency shift (MFS) and acceleration time (AT) were measured from the pulsed-wave Doppler trace of the pulmonary artery flow, obtained from the right parasternal short-axis view at the level of the pulmonary artery, and then PAS was calculated as the ratio of MFS to AT. The low variability assessed for intra- and inter-observer variability, day-to-day variability and image acquisition variability suggests that PAS can be measured consistently in horses. Further studies could be useful to assess the clinical usefulness of PAS in unhealthy horses, such as those affected by chronic respiratory diseases.

Increased Pulmonary Arterial Stiffness and Impaired Right Ventricle-Pulmonary Artery Coupling In PCOS

BACKGROUND

Polycystic ovary syndrome (PCOS) is the most common endocrine-metabolic disease in women in reproductive age, and occurs in one of 10 women. The disease includes menstrual irregularity and excess of male hormones and is the most common cause of female infertility. Dyspnea is a frequent symptom and is often thought to be due to obesity, and whether it is due to cardiac dysfunction is unknown.

OBJECTIVE

To evaluate right ventricle-pulmonary artery (RV-PA) coupling and pulmonary arterial stiffness in patients with PCOS.

METHODS

44 PCOS patients and 60 controls were included; venous blood samples were taken for laboratory tests and 2-D, m-mode and tissue doppler transthoracic echocardiography were performed for all the participants. P<0,05 was considered as statistically significant.

RESULTS

When compared to the control group, PCOS patients had higher pulmonary artery stiffness values (p=0,001), which were positively correlated with HOMA-IR (r=0,545 and p<0,001). RV-PA coupling was also impaired in 34% of the study patients.

CONCLUSION

Pulmonary artery stiffness is increased and RV-PA coupling is impaired in patients with PCOS. (Arq Bras Cardiol. 2021; 116(4):806-811).

Effects of angiotensin receptor neprilysin inhibition on pulmonary arterial stiffness in heart failure with reduced ejection fraction

The sacubitril/valsartan combination is an important agent used in the treatment of heart failure with reduced ejection fraction (HFrEF). Pulmonary artery stiffness (PAS) is an index developed to evaluate the pulmonary vascular bed. Changes in pulmonary vascular structures in HFrEF patients can affect PAS. In this study, we aimed to investigate the effect of sacubitril/valsartan on PAS in HFrEF patients. One hundred fifty HFrEF patients, who received sacubitril/valsartan therapy and continued for at least 6 months without interruption, were examined retrospectively. N-terminal pro-B-type natriuretic peptide levels (NT-proBNP), NYHA classes, Minnesota Living with Heart Failure Questionnaire (MLWHFQ) scores, New York Heart Association (NYHA) functional classes and echocardiograpic parameters such as left ventricular ejection fraction (LVEF), mean pulmonary artery pressure (mPAP), right ventricle myocardial performance index (RV-MPI), Tricuspid annular plane systolic excursion (TAPSE), right ventricular fractional area change (RV-FAC) and PAS changes were evaluated before and 6 months after sacubitril/valsartan treatment. PAS was calculated by using the maximal frequency shift and acceleration time of the pulmonary artery flow trace measured in the echocardiogram. PAS values were significantly reduced (23.8 ± 2.8 vs 19.1 ± 3.1 kHz/ms, p < 0.001) after the sacubitril/valsartan treatment. Sacubitril/valsartan treatment was associated with significant improvements in NYHA class and MLWHFQ scores; significant reductions in the NT-proBNP levels, mPAP, and RV-MPI, and significant increases in LVEF, TAPSE, and RV-FAC (p < 0.05). The significant reduction in the PAS value was significantly correlated with the improvements in the MLWFQ scores, NT-proBNP levels, mPAP, RV-MPI, TAPSE and RV-FAC. In HFrEF patients, switching from angiotensin-converting enzyme inhibitor/angiotensin II receptor blocker therapy to sacubitril/valsartan may result in reduction in PAS.

Evaluation of pulmonary artery stiffness in newly diagnosed adult patients with asthma

BACKGROUND

There are limited studies on the effects of asthma on cardiac function. Right ventricular dysfunction and pulmonary hypertension are cardiovascular complications that may be seen in advanced stages of the disease. Pulmonary artery stiffness (PAS), is a promising, relatively new echocardiographic index that has been reported to increase in right ventricular failure, providing information about pulmonary vascular bed.

AIM

In this study, we aimed to evaluate PAS, a marker of pulmonary artery elasticity, in adult-onset asthma.

METHODS

Ninety-nine nonsmokers who had a new asthma diagnosis between the ages of 18 and 65 years and 97 healthy controls with similar age and sex distribution were included in the study. PAS was calculated by dividing the maximal frequency shift of pulmonary flow (MFS) in pulmonary acceleration time (PAT).

RESULTS

Clinical and demographic characteristics of both groups were similar (P ˃ 0.05). PAS values were higher in the asthma group than in the control group (25.2 ± 4.5 vs 22.4 ± 4.1, P ˂0.001). TAPSE was lower in the case group (24.9 ± 2.0 vs 25.5 ± 2.1, P = 0.043), while RV MPI was higher (0.36 ± 0.07 vs 0.32 ± 0.06, P ˂0.001). In the multivariate linear regression analysis, RV MPI, RV Em, and TAPSE variables were independent predictors of PAS.

CONCLUSION

In our study, PAS values were higher in patients with newly diagnosed adult asthma and we found a significant weak correlation between PAS values and subclinical right ventricular dysfunction.