TAVI in 2015: who, where and how?

CT-Diagnosed Sarcopenia and Cardiovascular Biomarkers in Patients Undergoing Transcatheter Aortic Valve Replacement: Is It Possible to Predict Muscle Loss Based on Laboratory Tests?—A Multicentric Retrospective Analysis

Background: Patients with severe aortic valve stenosis (AS) often present with heart failure and sarcopenia. Sarcopenia, described as progressive degradation of skeletal muscle mass, has frequently been implicated as a cause of increased mortality, prolonged hospitalization and generalized poor outcome after transcatheter aortic valve replacement (TAVR). At present, sarcopenia is defined by the European Working Group on Sarcopenia in Older People (EWGSOP) based on clinical examination criteria and radiological imaging. The aim of the present study was to compare patients with Computed Tomography (CT)-diagnosed sarcopenia with regard to the expression of cardiovascular biomarkers in order to obtain additional, laboratory-chemical information. Methods: A total of 179 patients with severe AS were included in this retrospective study. Sarcopenia was determined via CT by measurement of the psoas muscle area (PMA), which was indexed to body surface area (PMAi). According to previous studies, the lowest tertile was defined as sarcopenic. Patients with (59/179) and without sarcopenia (120/179) in the overall cohort were compared by gender-specific cut-offs with regard to the expression of cardiovascular biomarkers such as brain natriuretic peptide (BNP), soluble suppression of tumorigenicity-2 (sST2), growth/differentiation of factor-15 (GDF-15), heart-type fatty-acid binding protein (H-FABP), insulin like growth factor binding protein 2 (IGF-BP2) and soluble urokinase-type plasminogen activator receptor (suPAR). Additionally, binary logistic regression analyses were calculated to detect possible predictors of the presence of sarcopenia. Results: No statistical differences regarding one-year survival could be detected between sarcopenic and non-sarcopenic patients in survival curves (log rank test p = 0.179). In the entire cohort, only BNP and hemoglobin (HB) showed a statistically significant difference, with only HB emerging as a relevant predictor for the presence of sarcopenia after binary logistic regression analysis (p = 0.015). No relevant difference in biomarker expression could be found in the male cohort. Regarding the female cohort, statistically significant differences were found in BNP, HB and hematocrit (HK). In binary logistic regression, however, none of the investigated criteria could be related to sarcopenia. Conclusion: Regardless of gender, patients with imaging-based muscle degradation did not demonstrate significantly different cardiovascular biomarker expression compared to those without it.

How Do Cardiovascular Biomarkers Behave in Patients with Severe Aortic Valve Stenosis with and without Echocardiographically Proven Pulmonary Hypertension?—A Retrospective Study of Biomarker Trends before and after Transcatheter Aortic Valve Replacement

Background: Since right heart catheterization is rarely performed in patients with severe aortic valve stenosis (AS), echocardiography is currently the tool of choice to determine the presence or absence of pulmonary hypertension (PH). The systolic pulmonary artery pressure (sPAP) has established itself as a reliable measurement value for this purpose. The aim of our study was to evaluate the behavior of plasma-level concentrations of novel cardiovascular biomarkers (sST2, GDF-15, H-FABP, IGF-BP2, and suPAR) in patients with severe AS and an sPAP < 40 mmHg in comparison to patients with an sPAP ≥ 40 mmHg before transcatheter aortic valve replacement (TAVR) and after TAVR (24 h, 96 h, 3 months, and 12 months). Methods: We retrospectively separated 85 patients with echocardiographic evidence of severe AS before TAVR procedure into two groups based on sPAP level. An sPAP of 40 mmHg was considered the cut-off value, with the absence of PH defined by an sPAP < 40 mmH (n = 32) and the presence of PH defined by an sPAP ≥ 40 mmHg (n = 53). Blood samples were drawn from each patient one day before TAVR and 24 h, 96 h, 3 months, and 12 months after TAVR. Plasma concentrations of the cardiovascular biomarkers sST2, GDF-15, H-FABP, IGF-BP2, and suPAR were determined and analyzed with univariate and multivariate binary logistic regression and AUROC curves. Results: Patients with severe AS and an sPAP ≥ 40 mmHg had significantly higher plasma concentrations of H-FABP (baseline: p = 0.022; 24 h: p = 0.012; 96 h: p = 0.037; 3 months: p = 0.006; 12 months: p = 0.030) and IGF-BP2 (baseline: p = 0.029; 24 h: p = 0.012; 96 h: p = 0.001; 3 months: p = 0.015; 12 months: p = 0.022) before and continuously up to 12 months after TAVR than did patients with an sPAP < 40 mmHg sST2, with the exception of the 12-month follow-up. We also consistently found significantly higher plasma concentrations in the sPAP ≥ 40 mmHg group (baseline: p = 0.007; 24 h: p = 0.006; 96 h: p = 0.014; 3 months: p ≤ 0.001; 12 months: p = 0.092), whereas suPAR had significantly elevated values at baseline and after 24 h in patients with echocardiographic evidence of PH and significantly decreased values after 3 months (baseline: p = 0.003; 24 h p = 0.041; 96 h: p = 0.127; 3 months: p = 0.006; 12 months: p = 0.477). Plasma concentrations of GDF-15 were only significantly different after 24 h (baseline: p = 0.075; 24 h: p = 0.016; 96 h: p = 0.101; 3 months: p = 0.244; 12 months: p = 0.090). In a multivariate binary logistic regression, atrial fibrillation, tricuspid annular plane systolic excursion (TAPSE), and sST2 at baseline were found to have a significant p-value < 0.050. Conclusion: In this descriptive study, sST2, H-FABP, and IGF-BP2 emerged as the cardiovascular biomarkers with the greatest potential with respect to echocardiographically PH detection in long-term follow-up after TAVR, as patients with an sPAP ≥ 40 mmHg had significantly continuously higher plasma biomarker concentrations than the corresponding cohort did, with an sPAP < 40 mmHg.

Comparison of PCWP and LVEDP Measurements in Patients with Severe Aortic Stenosis Undergoing TAVI-Same Same but Different?

BACKGROUND

Pulmonary capillary wedge pressure (PCWP) and left ventricular end-diastolic pressure (LVEDP) are often used as equivalents for determination of pulmonary hypertension (PH). PH is a comorbidity in patients with severe aortic valve stenosis (AS) and associated with limited prognosis. The aim of the study was to examine the role of differentiated classification basis of PCWP and LVEDP in patients planning for transcatheter aortic valve implantation (TAVI).

METHODS

284 patients with severe AS completed a combined left (LHC) and right heart catheterization (RHC) as part of a TAVI planning procedure. Patients were categorized twice into subtypes of PH according to 2015 European Society of Cardiology (ESC) guidelines-on the one hand with PCWP and on the other hand with LVEDP as classification basis. PCWP-LVEDP relationships were figured out using Kaplan-Meier curves, linear regressions and Bland-Altman analysis.

RESULTS

Regarding 1-year mortality, Kaplan-Meier analyses showed similar curves in spite of different classification bases of PH subtypes according to PCWP or LVEDP with exception of pre-capillary PH subtype. PCWP-LVEDP association in the overall cohort was barely present (R = 0.210, R² = 0.044). When focusing analysis on PH patients only a slightly increased linear regression was noted compared to the overall cohort (R = 0.220, R² = 0.048). The strongest regression was observed in patients with creatinine ≥ 132 µmol/L (R = 0.357, R² = 0.127) and in patients with mitral regurgitation ≥ II° (R = 0.326, R² = 0.106).

CONCLUSIONS

In patients with severe AS, there is a weak association between hemodynamic parameters measured by LHC and RHC. RHC measurements alone are not suitable for risk stratification with respect to one-year mortality. If analysis of hemodynamic parameters is necessary in patients with severe AS scheduled for TAVI, measurement results of LHC and RHC should be combined and LVEDP could serve as a helpful indicator for risk assessment.

Soluble ST2 as a Potential Biomarker for Risk Assessment of Pulmonary Hypertension in Patients Undergoing TAVR?

Background: Severe aortic valve stenosis (AS) is associated with pulmonary hypertension (PH) and has been shown to limit patient survival. Soluble suppression of tumorigenicity-2 (sST2) is a cardiovascular biomarker that has proven to be an important prognostic marker for survival in patients undergoing transcatheter aortic valve replacement (TAVR). The aim of this study was to assess the importance of the sST2 biomarker for risk stratification in patients with severe AS in presence or absence of PH. Methods: In 260 patients with severe AS undergoing TAVR procedure, sST2 serum level concentrations were analyzed. Right heart catheter measurements were performed in 152 patients, with no PH detection in 43 patients and with PH detection in 109 patients. Correlation analyses according to Spearman, AUROC analyses and Kaplan–Meier curves were calculated. Results: Patients with severe AS and PH showed significantly higher serum sST2 concentrations (p = 0.006). The sST2 cut-off value for non-PH patients regarding 1-year survival yielded 5521.15 pg/mL, whereas the cut-off value of PH patients was at a considerably higher level of 10,268.78 pg/mL. A cut-off value of 6990.12 pg/mL was related with a significant probability of PH presence. Survival curves showed that patients with severe AS and PH not only had higher 1-year mortality, but also that increased levels of sST2 plasma concentration were associated with earlier death. Conclusion: sST2 definitely has the potential to provide information about the presence of PH in patients with severe AS, in a noninvasive way.

On the Modeling of Transcatheter Therapies for the Aortic and Mitral Valves: A Review

Transcatheter aortic valve replacement (TAVR) has become a milestone for the management of aortic stenosis in a growing number of patients who are unfavorable candidates for surgery. With the new generation of transcatheter heart valves (THV), the feasibility of transcatheter mitral valve replacement (TMVR) for degenerated mitral bioprostheses and failed annuloplasty rings has been demonstrated. In this setting, computational simulations are modernizing the preoperative planning of transcatheter heart valve interventions by predicting the outcome of the bioprosthesis interaction with the human host in a patient-specific fashion. However, computational modeling needs to carry out increasingly challenging levels including the verification and validation to obtain accurate and realistic predictions. This review aims to provide an overall assessment of the recent advances in computational modeling for TAVR and TMVR as well as gaps in the knowledge limiting model credibility and reliability.

Temporal trends and socioeconomic differences in treatment and mortality following a diagnosis of aortic stenosis

AIMS

This study aims at determining the temporal trends and the socioeconomic differences in treatment and mortality following a diagnosis of aortic stenosis.

METHODS AND RESULTS

A total of 45,026 patients with a first-time diagnosis of aortic stenosis were identified in the Danish National Patient Registry in the period 2000-17. The risk of AVR within the first year after diagnosis decreased (OR = 1.84 in 2000-02 compared to 2015-16) and the risk was lower in the low-level educational group (OR = 0.85) and in the medium-level group (OR = 0.94) compared to high-level education. The risk of death after AVR within the first year decreased (OR = 2.25 in 2000-02 compared to 2015-16) and the risk was higher in the low-level educational group (OR = 1.32) and in the medium-level group (OR = 1.28) compared to high-level education. The risk of death within the first year after diagnosis, for those patients who did not get an AVR during the follow-up, decreased (OR = 3.08 in 2000-02 compared to 2015-16) and the risk was higher in the low-level educational group (OR = 1.21) and in the medium-level group (OR = 1.10) compared to high-level education.

CONCLUSION

Since 2000 there has been a decrease in both AVR treatment rate, mortality rate after AVR and mortality rate in patients not receiving AVR. For patients with lower-level education there is lower AVR treatment rate, higher mortality rate after AVR and higher mortality rate in patients not receiving AVR.

A validated computational framework to predict outcomes in TAVI

Transcatheter aortic valve implantation (TAVI) still presents complications: paravalvular leakage (PVL) and onset of conduction abnormalities leading to permanent pacemaker implantation. Our aim was testing a validated patient-specific computational framework for prediction of TAVI outcomes and possible complications. Twenty-eight TAVI patients (14 SapienXT and 14 CoreValve) were retrospectively selected. Pre-procedural CT images were post-processed to create 3D patient-specific implantation sites. The procedures were simulated with finite element analysis. Simulations' results were compared against post-procedural clinical fluoroscopy and echocardiography images. The computational model was in good agreement with clinical findings: the overall stent diameter difference was 2.6% and PVL was correctly identified with a post-processing algorithm in 83% of cases. Strains in the implantation site were studied to assess the risk of conduction system disturbance and were found highest in the patient who required pacemaker implantation. This study suggests that computational tool could support safe planning and broadening of TAVI.

TAVR-present, future, and challenges in developing countries

Transcatheter aortic valve replacement (TAVR) has become a well-established therapy for inoperable and high-risk patients of Aortic Stenosis in most of the part of the world. The technological advancements in the hemodynamic performance and design of valve prosthesis and also the data provided by various trials regarding the safety and efficacy of TAVR have widened the scope of TAVR in intermediate and low-risk groups also. The main focus of this review is to discuss the feasibility of TAVR in developing countries. Along with this review, it also gives a detailed outlook of the pros and cons of TAVR along with insight into the future of TAVR and its adoption into the low-risk group.

Oxidation-Reduction Potential in Patients undergoing Transcatheter or Surgical Aortic Valve Replacement

BACKGROUND

Aortic valve stenosis has gained increasingly more importance due to its high prevalence in elderly people. More than two decades ago, transcatheter aortic valve replacement emerged for patients who were denied surgery, and its noninferiority has been demonstrated in numerous studies. Oxidative stress has generated great interest because of its sensitivity to cell damage and the possibility of offering early hints of clinical outcomes. The aim of the present study was to investigate whether there is a significant difference between transcatheter (TAVR) or surgical aortic valve replacement (SAVR) in terms of the changes in oxidation-reduction potential (ORP) and antioxidant capacity. Therefore, we investigated perioperative oxidative stress levels and their influence on clinical outcomes.

METHODS

A total of 72 patients (50% TAVR versus 50% SAVR) were included in the present study. Static oxidation-reduction potential (sORP) and antioxidant capacity were measured using the RedoxSys™ Diagnostic System (Luoxis Diagnostics, USA) in serum samples drawn before and after surgery, as well as on the first postoperative day. In addition, clinical data were obtained to evaluate the clinical outcome of each case.

RESULTS

TAVR patients had higher preoperative sORP levels compared to the SAVR patients and more severe comorbidities. Unlike the TAVR cohort, patients in the SAVR group showed a significant difference in sORP from the pre- to postoperative levels. Capacity demonstrated higher preoperative levels in the SAVR cohort and also a greater difference postoperatively compared to the TAVR cohort. Regression analysis revealed a significant correlation between pre- and postoperative capacity levels (r = -0.9931, p < 0.0001), providing a method of predicting postoperative capacity levels by knowing the preoperative levels. According to the multivariable analysis, both sORP and antioxidant capacity are dependent on time point, baseline value, and type of surgery, with the largest variations observed for time effect and surgery method.

CONCLUSION

A high preoperative sORP level correlated to more severe illness in the TAVR patients. As the TAVR patients did not show significant differences in their preoperative levels, we assume that there was a smaller production of oxidative agents during TAVR due to the less invasive nature of the procedure. Baseline values and development of antioxidant capacity values strengthen this hypothesis. The significant correlation of pre- and postoperative capacity levels might allow high risk patients to be detected more easily and might provide more adequate and individualized therapy preoperatively. This trial is registered with clinicaltrials.gov, identifier: NCT 02488876.

Prediction of fluoroscopic angulations for transcatheter aortic valve implantation by CT angiography: influence on procedural parameters

Aims

Repeated angiograms to achieve an exactly orthogonal visualization of the aortic valve plane can substantially contribute to the total contrast amount required for transcatheter aortic valve implantation (TAVI). We investigated whether pre-procedural identification of an optimal fluoroscopic projection by cardiac computed tomography (CT) can significantly reduce the amount of a procedure-related contrast agent compared with angiographic determination of suitable angulations.

Methods and results

Eighty consecutive patients (81 ± 5 years, 55% male) with symptomatic severe aortic valve stenosis and normal renal function who underwent cardiac CT prior to TAVI were prospectively randomized. In 40 patients, a CT-predicted suitable angulation was used for the first aortic angiogram (CT cohort); in the other 40 patients, the first aortogram was acquired at LAO 10°/cranial 10 (angiography cohort). Additional aortograms were performed if no satisfactory view of the aortic valve plane was obtained. The number of aortograms needed to achieve a satisfactory fluoroscopic projection (1.2 ± 0.6 vs. 3.2 ± 1.7; P < 0.001) and the total amount of contrast agent per TAVI procedure were significantly lower in the CT cohort (95 ± 21 vs. 125 ± 36 mL; P < 0.001). Incidence of acute kidney injury was not significantly different. There was no significant difference regarding radiation dose, time of procedure, degree of post-procedural aortic regurgitation, complications and 30-day mortality between the cohorts.

Conclusion

Pre-procedural identification of a suitable fluoroscopic projection by cardiac CT significantly reduces a procedural contrast agent volume required for TAVI.

Is TAVR Ready for the Global Aging Population?

The emergence of the global pandemic of chronic diseases necessitates critical assessment of interventions that can be targeted at both the individual and population levels. Among cardiovascular diseases, the increasing prevalence of valvular heart diseases such as aortic stenosis parallels the rising burden of atherosclerotic cardiovascular diseases. As an alternative to surgical aortic valve replacement, technological innovation has allowed development of minimally invasive transcatheter aortic valve replacement (TAVR). This review examines whether TAVR can be applicable in low-resource regions across the world. Although revolutionary, TAVR is currently complex and requires a "Heart Team" approach for optimized patient care. We propose the emergence of telemedicine networks, newer valve designs that allow implementation of minimal approaches, and the use of minimal numbers of specialists for adapting TAVR to settings where surgical backup is not available. With efforts to reduce resource utilization, these alternate strategies have the potential to affect implementation of TAVR globally.

Transcatheter Aortic Valve Replacement: a Kidney's Perspective

Transcatheter aortic valve replacement (TAVR) has now emerged as a viable treatment option for high-risk patients with severe aortic stenosis (AS) who are not suitable candidates for surgical aortic valve replacement (SAVR). Despite encouraging published outcomes, acute kidney injury (AKI) is common and lowers the survival of patients after TAVR. The pathogenesis of AKI after TAVR is multifactorial including TAVR specific factors such as the use of contrast agents, hypotension during rapid pacing, and embolization; preventive measures may include pre-procedural hydration, limitation of contrast dye exposure, and avoidance of intraprocedural hypotension. In recent years, the number of TAVR performed worldwide has been increasing, as well as published data on renal perspectives of TAVR including AKI, chronic kidney disease, end-stage kidney disease, and kidney transplantation. This review aims to present the current literature on the nephrology aspects of TAVR, ultimately to improve the patients' quality of care and outcomes.

Current controversies in infective endocarditis

Infective endocarditis is a life-threatening disease caused by a focus of infection within the heart. For clinicians and scientists, it has been a moving target that has an evolving microbiology and a changing patient demographic. In the absence of an extensive evidence base to guide clinical practice, controversies abound. Here, we review three main areas of uncertainty: first, in prevention of infective endocarditis, including the role of antibiotic prophylaxis and strategies to reduce health care-associated bacteraemia; second, in diagnosis, specifically the use of multimodality imaging; third, we discuss the optimal timing of surgical intervention and the challenges posed by increasing rates of cardiac device infection.