Puerarin Modulates Hepatic Farnesoid X Receptor and Gut Microbiota in High-Fat Diet-Induced Obese Mice

Obesity is associated with alterations in lipid metabolism and gut microbiota dysbiosis. This study investigated the effects of puerarin, a bioactive isoflavone, on lipid metabolism disorders and gut microbiota in high-fat diet (HFD)-induced obese mice. Supplementation with puerarin reduced plasma alanine aminotransferase, liver triglyceride, liver free fatty acid (FFA), and improved gut microbiota dysbiosis in obese mice. Puerarin's beneficial metabolic effects were attenuated when farnesoid X receptor (FXR) was antagonized, suggesting FXR-mediated mechanisms. In hepatocytes, puerarin ameliorated high FFA-induced sterol regulatory element-binding protein (SREBP) 1 signaling, inflammation, and mitochondrial dysfunction in an FXR-dependent manner. In obese mice, puerarin reduced liver damage, regulated hepatic lipogenesis, decreased inflammation, improved mitochondrial function, and modulated mitophagy and ubiquitin-proteasome pathways, but was less effective in FXR knockout mice. Puerarin upregulated hepatic expression of FXR, bile salt export pump (BSEP), and downregulated cytochrome P450 7A1 (CYP7A1) and sodium taurocholate transporter (NTCP), indicating modulation of bile acid synthesis and transport. Puerarin also restored gut microbial diversity, the Firmicutes/Bacteroidetes ratio, and the abundance of Clostridium celatum and Akkermansia muciniphila. This study demonstrates that puerarin effectively ameliorates metabolic disturbances and gut microbiota dysbiosis in obese mice, predominantly through FXR-dependent pathways. These findings underscore puerarin's potential as a therapeutic agent for managing obesity and enhancing gut health, highlighting its dual role in improving metabolic functions and modulating microbial communities.

Effect of Neutrophil-to-Lymphocyte Ratio on Post-TAVR Mortality and Periprocedural Pulmonary Hypertension

Aims

To evaluate the impact of neutrophil-to-lymphocyte ratio (NLR) on periprocedural pulmonary hypertension (PH) and 3-month all-cause mortality in patients with aortic stenosis (AS) who underwent transcatheter aortic valve replacement (TAVR) and to develop a nomogram for predicting the mortality for these patients.

Methods and Results

124 patients undergoing TAVR were categorized into three groups according to systolic pulmonary artery pressure (sPAP): Group I (no PH, n = 61) consisted of patients with no pre- and post-TAVR PH; Group II (improved PH, n = 35) consisted of patients with post-TAVR systolic pulmonary artery pressure (sPAP) decreased by more than 10 mmHg compared to pre-TAVR levels; and Group III (persistent PH, n = 28) consisted of patients with post-TAVR sPAP no decrease or less than 10 mmHg, or new-onset PH after the TAVR procedure. The risk of all-cause mortality within 3 months tended to be higher in Group II (11.4%) and Group III (14.3%) compared to Group I (3.3%) (P=0.057). The multinomial logistic regression analysis demonstrated a positive correlation between NLR and both improved PH (OR: 1.182, 95% CI: 1.036-1.350, P=0.013) and persistent PH (OR: 1.181, 95% CI: 1.032-1.352, P=0.016). Kaplan-Meier analysis revealed a significant association between higher NLR and increased 3-month all-cause mortality (16.1% vs. 3.1% in lower NLR group, P=0.021). The multivariable Cox regression analysis confirmed that NLR was an independent predictor for all-cause mortality within 3 months, even after adjusting for clinical confounders. A nomogram incorporating five factors (BNP, heart rate, serum total bilirubin, NLR, and comorbidity with coronary heart disease) was developed. ROC analysis was performed to discriminate the ability of the nomogram, and the AUC was 0.926 (95% CI: 0.850-1.000, P < 0.001).

Conclusions

Patients with higher baseline NLR were found to be at an increased risk of periprocedural PH and all-cause mortality within 3 months after TAVR.

Impact of pulmonary hypertension on short-term outcomes in patients undergoing surgical aortic valve replacement for severe aortic valve stenosis

OBJECTIVES

In patients with left heart disease and severe aortic stenosis (AS), pulmonary hypertension (PH) is a common comorbidity and predictor of poor prognosis. Untreated AS aggravates PH leading to an increased right ventricular afterload and, in line to right ventricular dysfunction. The surgical benefit of aortic valve replacement (AVR) in elderly patients with severe AS and PH could be limited due to the multiple comorbidities and poor outcomes. Therefore, we purposed to investigate the impact of PH on short-term outcomes in patients with moderate to severe AS who underwent surgical AVR in our heart center.

METHODS

In this study we retrospectively analyzed a cohort of 99 patients with severe secondary post-capillary PH who underwent surgical AVR (AVR + PH group) at our heart center between 2010 and 2021 with a regard to perioperative outcomes. In order to investigate the impact of PH on short-term outcomes, the control group of 99 patients without pulmonary hypertension who underwent surgical AVR (AVR group) at our heart center with similar risk profile was accordingly analyzed regarding pre-, intra- and postoperative data.

RESULTS

Atrial fibrillation occurred significantly more often (p = .013) in patients who suffered from PH undergoing AVR. In addition, the risk for cardiac surgery (EUROSCORE II) was significantly higher (p < .001) in the above-mentioned group. Likewise, cardiopulmonary bypass time (p = .018), aortic cross-clamp time (p = .008) and average operation time (p = .009) were significantly longer in the AVR + PH group. Furthermore, the in-hospital survival rate was significantly higher (p = .044) in the AVR group compared to the AVR + PH group. Moreover, the dialysis rate was significantly higher (p < .001) postoperatively in patients who suffered PH compared to the patients without PH undergoing AVR.

CONCLUSION

In our study, patients with severe PH and severe symptomatic AS who underwent surgical aortic valve replacement showed adverse short-term outcomes compared to patients without PH.

Assessing Complex Left Ventricular Adaptations in Aortic Stenosis Using Personalized 3D + time Cardiac MRI Modeling

Left ventricular adaptations can be a complex process under the influence of aortic stenosis (AS) and comorbidities. This study proposed and assessed the feasibility of using a motion-corrected personalized 3D + time LV modeling technique to evaluate the adaptive and maladaptive LV response to aid treatment decision-making. A total of 22 AS patients were analyzed and compared against 10 healthy subjects. The 3D + time analysis showed a highly distinct and personalized pattern of remodeling in individual AS patients which is associated with comorbidities and fibrosis. Patients with AS alone showed better wall thickening and synchrony than those comorbid with hypertension. Ischemic heart disease in AS caused impaired wall thickening and synchrony and systolic function. Apart from showing significant correlations to echocardiography and clinical MRI measurements (r: 0.70-0.95; p < 0.01), the proposed technique helped in detecting subclinical and subtle LV dysfunction, providing a better approach to evaluate AS patients for specific treatment, surgical planning, and follow-up recovery.

Utility of the tricuspid annular tissue doppler systolic velocity and pulmonary artery systolic pressure relationship in right ventricular systolic function assessment: A pilot study

BACKGROUND

Tricuspid annular plane systolic excursion (TAPSE) to pulmonary artery systolic pressure (PASP) ratio has been validated as a valuable noninvasive measure of right ventricular (RV) elastance and systolic function. However, the more reliable TA systolic (s') velocity measure of RV systolic function compared to TAPSE has not been previously studied.

METHODS

We conducted a pilot study using several variables of RV function in 50 patients with the main aim to determine which numerical expression between TA TDI s'/PASP and TAPSE/PASP ratio was most useful.

RESULTS

In a stepwise multiple regression analysis, TA TDI s'/PASP ratio (p < .0002); LVOT VTI/RVOT VTI ratio (p < .0002); RVOT VTI (p < .0047); TAPSE/PASP ratio (p < .0259) and TA TDI e' (p < .0292) were best in discriminating normal versus abnormal RV systolic function. Using receiver operator curve analysis, cut-off values for both TA TDI s'/PASP (>3.9 mm/c/mmHg) had 82.1% sensitivity and 77.3% specificity while the TAPSE/PASP (>.61 mm/mmHg) had 89.3% sensitivity and 68.2% specificity in identifying normal RV function in our studied population.

CONCLUSION

Our results indicate that TA TDI s'/PASP is a better mathematical expression when examining the relationship between RV contractility and RV resistance relationship. Furthermore, we also found that inclusion of RVOT VTI, RV diastolic properties, and left ventricular systolic function are important determinants of RV systolic function assessments and should be routinely included. Additional prospective studies are now needed to confirm these results using hemodynamic data.

Impact of Pulmonary Hypertension on Mortality after Surgery for Aortic Stenosis

Background and Objectives: The prognosis of patients with aortic stenosis (AS) adding pulmonary hypertension (PHT) is worse than in those with normal pulmonary artery pressure (PAP), and there are few results reported for the association between PHT and adverse outcomes of AS. We aimed to determine the predictive factors for the development of PHT in patients with surgical AS and to identify those factors that may predict the surgical prognosis. We aimed to identify the independent predictors for PHT regression at 2 years after surgery. Additionally, we tried to evaluate the involvement of PHT as an additional perioperative risk factor in patients with AS undergoing surgical aortic valve replacement (AVR). Materials and Methods: We carried out a two-year prospective study on 340 patients with AS undergoing surgical AVR. Results: The independent predictors for the occurrence of PHT in patients with surgical AS were: age > 75 years (RR = 6, p = 0.001), a restrictive left ventricle diastolic filling pattern (LVDFP) (RR = 9, p = 0.001) and associated moderate mitral regurgitation (MR) (RR = 9, p = 0.0001). The presence of severe PHT increased by 7.6 times the early postoperative risk of death, regardless of the presence of other parameters. The independent predictors for early postoperative mortality were: severe PHT, restrictive left ventricle diastolic pattern, age > 75 years, interventricular septum (IVS) thickness >18 mm and the presence of comorbidities. Conclusions: The presence of a severe PHT in patients with AS undergoing surgical AVR is associated with an early postoperative increased mortality rate. The mean PAP is a more reliable parameter for prognosis appreciation than the LV systolic function.

Severe Aortic Valve Stenosis and Pulmonary Hypertension: A Systematic Review of Non-Invasive Ways of Risk Stratification, Especially in Patients Undergoing Transcatheter Aortic Valve Replacement

Patients with severe aortic valve stenosis and concomitant pulmonary hypertension show a significantly reduced survival prognosis. Right heart catheterization as a preoperative diagnostic tool to determine pulmonary hypertension has been largely abandoned in recent years in favor of echocardiographic criteria. Clinically, determination of echocardiographically estimated systolic pulmonary artery pressure falls far short of invasive right heart catheterization data in terms of accuracy. The aim of the present systematic review was to highlight noninvasive possibilities for the detection of pulmonary hypertension in patients with severe aortic valve stenosis, with a special focus on cardiovascular biomarkers. A total of 525 publications regarding echocardiography, cardiovascular imaging and biomarkers related to severe aortic valve stenosis and pulmonary hypertension were analyzed in a systematic database analysis using PubMed Central®. Finally, 39 publications were included in the following review. It was shown that the current scientific data situation, especially regarding cardiovascular biomarkers as non-invasive diagnostic tools for the determination of pulmonary hypertension in severe aortic valve stenosis patients, is poor. Thus, there is a great scientific potential to combine different biomarkers (biomarker scores) in a non-invasive way to determine the presence or absence of PH.

Acute haemodynamic impact of transcatheter aortic valve implantation in patients with severe aortic stenosis

Aims

There are limited data about the intraprocedural haemodynamic study performed immediately before and after transcatheter aortic valve implantation (TAVI) in patients with severe aortic stenosis (AS). We aimed to evaluate the acute haemodynamic impact of TAVI in patients with severe AS and to investigate invasive and non‐invasive parameters predicting all‐cause mortality.

Methods and results

A total of 245 consecutive AS patients (43% male, mean age 80.3 ± 7.3 years) undergoing TAVI were enrolled. Intraprocedural left heart catheterization (LHC) and echocardiogram before and after TAVI were performed. The clinical endpoint was the death for any cause. LHC after TAVI revealed significant changes in aortic and left ventricular (LV) pressures, including indexes of intrinsic myocardial contractility and diastolic function such as positive dP/dT (1128.9 ± 398.7 vs. 806.3 ± 247.2 mmHg/s, P ˂ 0.001) and negative dP/dT (1310.7 ± 431.1 vs. 1075.1 ± 440.8 mmHg/s, P ˂ 0.001). Post‐TAVI echo showed a significant reduction in LV end‐diastolic (P = 0.036) and end‐systolic (P ˂ 0.001) diameters, improvement in LV ejection fraction (from 55 ± 12% to 57.2 ± 10.5%, P ˂ 0.001), and pulmonary artery systolic pressure (42.1 ± 14.2 vs. 33.1 ± 10.7 mmHg, P < 0.001). After a mean follow‐up time interval of 24 months, 47 patients died. Post‐TAVI significant aortic regurgitation at echocardiography was the only independent predictor of mortality (hazard ratio 5.592, confidence interval 1.932–16.184, P = 0.002).

Conclusions

Left heart catheterization performed immediately before and after prosthesis release offers a unique insight in the assessment of LV adaptation to severe AS and the impact of TAVI on LV, catching changes in indexes of intrinsic contractility and myocardial relaxation. Aortic regurgitation assessed by echocardiography was the only independent predictor of mortality in patients undergoing TAVI.

Valvulo-Arterial Impedance and Dimensionless Index for Risk Stratifying Patients With Severe Aortic Stenosis

The hemodynamic effects of aortic stenosis (AS) consist of increased left ventricular (LV) afterload, reduced myocardial compliance, and increased myocardial workload. The LV in AS patients faces a double load: valvular and arterial loads. As such, the presence of symptoms and occurrence of adverse events in AS should better correlate with calculating the global burden faced by the LV in addition to the transvalvular gradient and aortic valve area (AVA). The valvulo-arterial impedance (Zva) is a useful parameter providing an estimate of the global LV hemodynamic load that results from the summation of the valvular and vascular loads. In addition to calculating the global LV afterload, it is paramount to estimate the stenosis severity accurately. In clinical practice, the management of low-flow low-gradient (LF-LG) severe AS with preserved LV ejection fraction requires careful confirmation of stenosis severity. In addition to the Zva, the dimensionless index (DI) is a very useful parameter to express the size of the effective valvular area as a proportion of the cross-section area of the left ventricular outlet tract velocity-time integral (LVOT-VTI) to that of the aortic valve jet (dimensionless velocity ratio). The DI is calculated by a ratio of the sub-valvular velocity obtained by pulsed-wave Doppler (LVOT-VTI) divided by the maximum velocity obtained by continuous-wave Doppler across the aortic valve (AV-VTI). In contrast to AVA measurement, the DI does not require the calculation of LVOT cross-sectional area, a major cause of erroneous assessment and underestimation of AVA. Hence, among patients with LG severe AS and preserved LV ejection fraction, calculation of DI in routine echocardiographic practice may be useful to identify a subgroup of patients at higher risk of mortality who may derive benefit from aortic valve replacement. This article aims to elucidate the Zva and DI in different clinical situations, correlate with the standard indexes of AS severity, LV geometry, and function, and thus prove to improve risk stratification and clinical decision making in patients with severe AS.

Importance of Tricuspid Regurgitation Velocity Threshold in Risk Assessment of Pulmonary Hypertension-Long-Term Outcome of Patients Submitted to Aortic Valve Replacement

Background: The upper physiological threshold for tricuspid regurgitation velocity (TRV) of 2.8 m/s proposed by the Pulmonary Hypertension (PH) guidelines had been questioned. The aim of this study was to evaluate the prognostic significance of preoperative PH in patients with aortic stenosis, long-term after valve replacement, using two different TRV thresholds (2.55 and 2.8 m/s). Methods: Four hundred and forty four patients were included (mean age 73 ± 9 years; 55% male), with a median follow-up of 5.8 years (98% completed). Patients were divided into three PH probability groups according to guidelines (low, intermediate and high) for both thresholds (TRV ≤ 2.8 m/s and TRV ≤ 2.55 m/s), using right atrial area>18 cm² and right ventricle/left ventricle ratio>1 as additional echocardiographic variables. Results: In patients with measurable TRV (n = 304), the low group mortality rate was 25% and 30%, respectively for 2.55 and 2.8 m/s TRV thresholds. The intermediate group with TRV > 2.55 m/s was an independent mortality risk factor (HR 2.04; 95% CI: 1.91 to 3.48, p = 0.01), in contrast to the intermediate group with TRV>2.8 m/s (HR 1.44; 95% CI: 0.89 to 2.32, p = 0.14). Both high probability groups were associated with an increased mortality risk, as compared to their respective low groups. When including all patients (with measurable and non-measurable TRV), both intermediate groups remained independently associated with an increased mortality risk: HR 1.62 (95% CI 1.11 to 2.35 p = 0.01) for the new cut-off point; and HR 1.43 (95% CI: 0.96 to 2.13, p = 0.07) for guidelines threshold. Conclusion: A TRV threshold of 2.55 m/s, together with right cavities measures, allowed a better risk assessment of patients with PH secondary to severe aortic stenosis, with or without tricuspid regurgitation.

Echocardiographic assessment of aortic stenosis: a practical guideline from the British Society of Echocardiography

The guideline provides a practical step-by-step guide in order to facilitate high-quality echocardiographic studies of patients with aortic stenosis. In addition, it addresses commonly encountered yet challenging clinical scenarios and covers the use of advanced echocardiographic techniques, including TOE and Dobutamine stress echocardiography in the assessment of aortic stenosis.

Watchful waiting care or early intervention in asymptomatic severe aortic stenosis: Where we are

Aortic stenosis, the most common valvular heart disease in Western countries, affects predominantly older people. Prompt aortic valve replacement is undoubtedly indicated in symptomatic patients. Management of asymptomatic patients is nowadays shifting from a conservative approach to early aortic valve replacement, as multimodality imaging is increasingly available. However, multimodality imaging has led to multiple prognostic parameters and complex algorithms, as well as a new staging classification that has left patients and physicians somewhat puzzled. We highlight the value of thorough serial clinical examinations, Doppler echocardiography and exercise testing when caring for a growing aortic stenosis population, including that has no or limited access to multimodality imaging. Evidence for early aortic valve replacement versus conservative management in asymptomatic patients with severe aortic stenosis is biased by the lack of serial stress testing evaluation; 30% of so-called asymptomatic patients were in fact symptomatic, and thus were clear candidates for aortic valve replacement in the above-mentioned studies. Randomized trials of aortic valve replacement versus conservative management that include serial stress testing evaluation are needed to ascertain whether early aortic valve replacement actually improves clinical outcome in asymptomatic patients with severe aortic stenosis. Less interventional medicine and healthcare resource utilization can result in better health.

Impact of Preoperative Measurement of Right Heart Chambers in the Evaluation of Pulmonary Hypertension Following Aortic Valve Replacement

BACKGROUND

Severe pulmonary hypertension (PH) in patients with aortic stenosis is related to poor prognosis following aortic valve replacement (AVR). Current European PH guidelines recommend adding two different echocardiographic signs to tricuspid regurgitation velocity (TRV) in PH estimation, classifying its probability as low (TRV ≤ 2.8 m/s), intermediate (TRV 2.9-3.4 m/s), and high (TRV > 3.4 m/s). The right ventricle is an important determinant of prognosis in PH. The goal of this study was to analyze the value of right atrial area > 18 cm² and right ventricular/left ventricular ratio > 1 in the long-term prognosis following AVR, mainly in the intermediate probability group.

METHODS

This study included 429 consecutive patients (mean age, 73 ± 8 years; 55% male) with a median follow-up of 4.25 years (completed in 98%). Patients were divided into low (n = 247), intermediate (n = 117), and high probability groups (n = 65). The intermediate probability group was divided into two subgroups: subgroup 2a (n = 27; TRV nonmeasurable or ≤ 2.8 m/s and two signs present) and subgroup 2b (n = 90; TRV 2.9-3.4 m/s, and none or only one sign present).

RESULTS

Overall mortality rates during follow-up of the low, intermediate, and high probability groups were 24%, 32%, and 42%, respectively. High PH probability was an independent predictor of all-cause mortality (hazard ratio [HR], 1.82; 95% CI, 1.11-3.00), but the intermediate probability group did not reach significance following multivariate analysis (HR, 1.40; 95% CI, 0.91-2.16). When the intermediate probability group was divided into subgroups, the subgroup 2a mortality rate (56%) was higher than that of both subgroup 2b (24%; P = .002) and the low probability group (24%; P < .001). Following multivariate analysis, subgroup 2a showed a significantly higher mortality (HR, 2.13; 95% CI, 1.11-4.10) in contrast to subgroup 2b (HR, 1.24; 95% CI, 0.75-2.05), both compared with the low probability group.

CONCLUSIONS

Incorporating measurement of the right cavities into the PH probability model in the assessment of long-term prognosis following AVR allowed better risk discrimination, especially in the intermediate probability group.

Impact of Right Ventricular Systolic Dysfunction on Outcome in Aortic Stenosis

Background:

Pulmonary hypertension is an established outcome predictor in patients with aortic stenosis (AS), but the prognostic impact of right ventricular dysfunction has not been well studied.

Methods:

We included 2181 patients (50.4% men; mean age, 77 years) with aortic valve area <1.3 cm 2 and analyzed the occurrence of all-cause death during follow-up according to tricuspid annular plane systolic excursion (TAPSE) quartiles.

Results:

Patients in the lowest quartile (TAPSE <17 mm) were at a high risk of death, whereas survival was comparable for the 3 other quartiles. Five-year survival was 55±2% for TAPSE <17 mm, 72±2% for TAPSE of 17 to 20 mm, 71±2% for TAPSE of 20 to 24 mm, and 73±2% for TAPSE >24 mm (overall P <0.001). TAPSE <17 mm was associated with increased mortality after adjustment for established prognostic factors (adjusted hazard ratio [HR], 1.55 [95% CI, 1.21–1.97]) and after further adjustment for aortic valve replacement (AVR; adjusted HR, 1.47 [95% CI, 1.15–1.87]). The excess mortality risk associated with TAPSE <17 mm was noticed in both patients managed initially conservatively (adjusted HR, 1.46 [95% CI, 1.20–1.76]) and patients who underwent early (within 3 months after diagnosis) AVR (adjusted HR, 1.61 [95% CI, 1.03–2.52]). In asymptomatic patients with severe AS and preserved ejection fraction, TAPSE <17 mm was independently predictive of mortality (adjusted HR, 2.14 [95% CI, 1.31–3.51]). Early AVR was associated with similar survival benefit in TAPSE <17 and ≥17 mm (adjusted HR, 0.23 [95% CI, 0.16–0.34] for TAPSE <17 mm, adjusted HR, 0.26 [95% CI, 0.19–0.35] for TAPSE ≥17 mm; P for interaction, 0.97).

Conclusions:

Right ventricular dysfunction is an important and independent predictor of mortality in AS. TAPSE <17 mm at the time of AS diagnosis is a marker of poor survival under conservative management and after AVR even in asymptomatic patients with severe AS. AVR was associated with a pronounced reduction in mortality independent of TAPSE suggesting that AVR should be discussed before right ventricular dysfunction occurs in severe AS.

Association Between Pulmonary Hypertension and Transcatheter Aortic Valve Replacement: Analysis of a Nationwide Inpatient Sample Database

INTRODUCTION

This study was done to review the association of pulmonary hypertension (PH) with Transcatheter Aortic Valve Replacement (TAVR) procedures done in the US for years 2010 to 2012.

METHODS

We used Nationwide Inpatient Sample (NIS) data to extract data for patients who were hospitalized with a primary/secondary diagnosis of TAVR as specified by International Classification of Disease (ICD-9) codes 35.05 and 35.06. PH was identified with ICD-9 codes 416.0 and 416.8. Logistic regression models were used to analyze the association between PH and clinical outcomes of TAVR.

RESULTS

A total of 8,824 weighted discharges were identified with a primary/secondary diagnosis of TAVR, of which 1,976 (22.4%) also had PH. Mean age of patients undergoing TAVR with and without PH was 81.4 and 81.1 years, respectively. More females had a diagnosis of PH with TAVR when compared to males, (56.9% vs. 43.1). When controlling for demographics, diabetes and hypertension; the association between PH and TAVR was statistically significant (p<.0001). Estimated odds of TAVR with PH was 5.46 (95% CI: 4.63, 6.41) times greater than for TAVR without PH. Similarly, the estimated odds for a length of stay greater than 1 week for TAVR with PH was 1.43 (95% CI: 1.12, 1.82; p=.0034) times greater than odds for TAVR without PH. PH was not statistically significant for in-hospital mortality in patients receiving TAVR (p=0.7067).

CONCLUSION

This study suggests that underlying PH does not influence the immediate mortality of patients underlying TAVR. Further studies are needed to delve into the bearing of PH on TAVR.

Haemodynamic mechanisms and long-term prognostic impact of pulmonary hypertension in patients with severe aortic stenosis undergoing valve replacement

AIMS

We aimed to investigate the prevalence, detailed invasive haemodynamics, and prognostic impact of pulmonary hypertension (PH) in severe aortic stenosis (AS).

METHODS AND RESULTS

We studied 503 patients (mean age 74 ± 10 years) with severe AS (indexed aortic valve area 0.4 ± 0.1 cm² /m² , left ventricular ejection fraction 57 ± 12%) undergoing left and right heart catheterization prior to aortic valve replacement. Median follow-up was 3.7 (interquartile range 2.6-5.4) years. Baseline PH (mean pulmonary artery pressure ≥ 25 mmHg) was found in 239 (48%) patients: 31 patients had pre-capillary PH [mean pulmonary artery wedge pressure (mPAWP) ≤ 15 mmHg], 144 had isolated post-capillary PH [IpcPH; mPAWP > 15 mmHg, pulmonary vascular resistance (PVR) ≤ 3 Wood units (WU)], and 64 had combined pre- and post-capillary PH (CpcPH; mPAWP > 15 mmHg, PVR > 3 WU). Patients with CpcPH had higher mortality than those with IpcPH, pre-capillary PH, and without PH. In the multivariate analysis, CpcPH remained an independent predictor of death (hazard ratio 4.39, 95% confidence interval 2.40-8.03; P < 0.001). Patients with CpcPH had higher mPAWP (26 ± 7 vs. 22 ± 5 mmHg) and lower pulmonary arterial capacitance (1.5 ± 0.6 vs. 2.9 ± 1.2 mL/mmHg) than IpcPH patients but similar left ventricular end-diastolic pressure (LVEDP; 25 ± 7 vs. 25 ± 7 mmHg). A smaller LVEDP-mPAWP difference was related to larger left atrial size, atrial fibrillation, and more severe mitral regurgitation.

CONCLUSIONS

In patients with severe AS, PH is common but underlying mechanisms differ. Patients with CpcPH have higher mPAWP, lower pulmonary arterial capacitance, and worse survival than all other groups. Left atrial dysfunction and mitral regurgitation seem to be drivers of high mPAWP in CpcPH.

Increased risk profile in the treatment of patients with symptomatic degenerative aortic valve stenosis over the last 10 years

Introduction

Currently, Cardiology Centres are overfilled with patients with degenerative aortic valve stenosis (DAS), usually eldery, with severe concommittant comorbidities, who are referred for further decisions and possible intervention.

Aim

To evaluate changes in the risk profile of patients with severe DAS admitted to the cardiology department a decade ago compared with patients currently being admitted.

Material and methods

We retrospectively evaluated all patients admitted with confirmed severe DAS, hospitalized during 2005-2006 (group I: 140 patients) and in 2016 (group II: 152 patients), admitted for aortic valve intervention. A standard transthoracic echocardiogram, cardiovascular symptom and risk factor distribution, perioperative risk with the logistic EuroSCORE II and STS mortality scores were obtained.

Results

Patients in group II were significantly older (p < 0.001), had more cardiovascular risk factors, and more often presented with atrial fibrillation (27% vs. 11.4%, p = 0.001), renal impairment (34.9% vs. 22.8%; p = 0.024), severe lung disease (17.1% vs. 2.1%, p < 0.001), and extracardiac arteriopathy (40.1% vs. 17.8%, p < 0.001). The aortic valve area (AVA) (p = 0.356), mean-transvalvular pressure gradient (p = 0.215), and left ventricular ejection fraction (p = 0.768) were similar in both groups. However, the prevalence of pulmonary hypertension, severe mitral regurgitation, and low-flow, low-gradient DAS were 3.1-, 8.4- and 1.84-fold more frequent in group II than group I. The percentages of subjects with EuroSCORE II and STS scores ≥ 4% in 2005-2006 were 7.1% and 6.4%, as compared to 27% and 26.3% in 2016 (both p < 0.001). 22% of patients in 2016, as compared to 31% in 2005/2006, were considered ineligible for DAS intervention.

Conclusions

In just a decade, the risk profile of patients admitted with DAS has increased hugely, mainly due to older age, accumulation of comorbidities and more advanced disease at presentation. Although transcatheter aortic valve intervention has expanded the indications for intervention in high-risk patients, the number of patients disqualified from interventional treatment remains high.

Pulmonary Hypertension in Aortic and Mitral Valve Disease

In patients with aortic and/or mitral valve disease the presence of pulmonary hypertension (PH) indicates a decompensated state of the disease with left ventricular and left atrial dysfunction and exhausted compensatory mechanism, i.e., a state of heart failure. Pulmonary hypertension in this context is the consequence of the backwards transmission of elevated left atrial pressure. In this form of PH, pulmonary vascular resistance is initially normal (isolated post-capillary PH). Depending on the extent and chronicity of left atrial pressure elevation additional pulmonary vascular remodeling may occur (combined pre- and post-capillary PH). Mechanical interventions for the correction of valve disease often but not always reduce pulmonary pressures. However, the reduction in pulmonary pressures is often modest, and persistent PH in these patients is common and a marker of poor prognosis. In the present review we discuss the pathophysiology and clinical impact of PH in patients with aortic and mitral valve disease, the comprehensive non-invasive and invasive diagnostic approach required to define treatment of PH, and recent insights from mechanistic studies, registries and randomized studies, and we provide an outlook regarding gaps in evidence, future clinical challenges, and research opportunities in this setting.