Impact of aortic valve calcification severity on device success after transcatheter aortic valve replacement

Aortic Valve Calcium Score: Applications in Clinical Practice and Scientific Research-A Narrative Review

In this narrative review, we investigate the essential role played by the computed tomography Aortic Valve Calcium Score (AVCS) in the cardiovascular diagnostic landscape, with a special focus on its implications for clinical practice and scientific research. Calcific aortic valve stenosis is the most prevalent type of aortic stenosis (AS) in industrialized countries, and due to the aging population, its prevalence is increasing. While transthoracic echocardiography (TTE) remains the gold standard, AVCS stands out as an essential complementary tool in evaluating patients with AS. The advantage of AVCS is its independence from flow; this allows for a more precise evaluation of patients with discordant findings in TTE. Further clinical applications of AVCS include in the assessment of patients before transcatheter aortic valve replacement (TAVR), as it helps in predicting outcomes and provides prognostic information post-TAVR. Additionally, we describe different AVCS thresholds regarding gender and the anatomical variations of the aortic valve. Finally, we discuss various scientific studies where AVCS was applied. As AVCS has some limitations, due to the pathophysiologies of AS extending beyond calcification and gender differences, scientists strive to validate contrast-enhanced AVCS. Furthermore, research on developing radiation-free methods of measuring calcium content is ongoing.

ACURATE neo2 Versus SAPIEN 3 Ultra Transcatheter Heart Valve in Severe Aortic Valve Calcification: A Propensity-Matched Analysis

BACKGROUND

Comparative data on transcatheter self-expanding ACURATE neo2 (NEO2) and balloon-expandable SAPIEN 3 Ultra prostheses in technically challenging anatomy of severe aortic valve calcified aortic annuli are scarce.

METHODS

A total of 1987 patients with severe native aortic stenosis treated with the self-expanding NEO2 (n=1457) or balloon-expandable SAPIEN 3 Ultra (n=530) from January 2017 to April 2023 were evaluated. The primary end point was procedural outcome according to the Valve Academic Research Consortium 3 definitions. Propensity matching defined 219 pairs with severe calcification (calcium density cutoff, 758 AU/cm2) of the native aortic valve.

RESULTS

Technical success (90.4% versus 91.8%; risk difference, 1.4% [95% CI, -4.4 to -7.2]; P=0.737) and device success at 30 days (80.8% versus 75.8%; risk difference, -5.0% [95% CI, -13.2 to 3.1]; P=0.246) were comparable between NEO2 and SAPIEN 3 Ultra. The rate of severe prosthesis-patient mismatch (1.1% versus 10.1%; risk difference, 10.0% [95% CI, 4.0-13.9]; P<0.001) and mean transvalvular gradient ≥20 mm Hg (2.8% versus 14.3%; risk difference, 11.5% [95% CI, 5.8-17.1]; P<0.001) was lower with NEO2. The rate of more-than-mild paravalvular leakage or valve-in-valve due to paravalvular leakage was significantly higher (6.2% versus 0.0%; risk difference, 6.2% [95% CI, -10.1 to -2.7]; P=0.002), and there was a tendency for a higher rate of device embolization or migration (1.8% versus 0.0%; risk difference, -1.8% [95% CI, -4.1 to 0.4]; P=0.123) with NEO2. Multivarate regression revealed no independent impact of transcatheter heart valve selection on device success (odds ratio, 0.93 [95% CI, 0.48-1.77]; P=0.817).

CONCLUSIONS

In patients with severely calcified annuli, supraannular implantation of NEO2 showed hemodynamic advantages. Nevertheless, NEO2 was associated with a higher incidence of relevant paravalvular leakage and a numerically higher rate of device embolization than SAPIEN 3 Ultra in this particular patient group.

Assess the Outcomes of Transcatheter Aortic Valve Replacement in Bicuspid Valve with Mixed Disease versus Predominant Aortic Stenosis

Purpose

In mixed aortic valve disease (MAVD), the results of transcatheter aortic valve replacement (TAVR) are conflicting. There is limited data on the outcomes of TAVR in patients with bicuspid aortic valve (BAV) and MAVD. The objective of this study is to compare outcomes after TAVR in BAV patients with MAVD and predominant aortic stenosis (PAS).

Patients and Methods

Patients with BAV who underwent TAVR between January 2016 and April 2023 were included. The primary outcome was device success. The secondary endpoints were periprocedural mortality and other complications as defined by the Valve Academic Research Consortium-3 (VARC-3). Propensity score matching was used to minimize potential confounding.

Results

A total of 262 patients were included in this study, 83 of whom had MAVD. The median age was 72 years, and 55.7% were male. The baseline comorbidity risk files were comparable between the two groups. Patients with MAVD had more mitral regurgitation, tricuspid regurgitation and pulmonary hypertension, larger annular and left ventricular outflow tract dimensions, and more severe calcification than PAS. In the unmatched population, MAVD patients had similar device success rate (69.9% vs 79.9%, P=0.075) and 30-day mortality (3.6% vs 3.4%, P=1) compared to PAS. Propensity score matching resulted in 66 patient pairs. Device success rate were still comparable in the matched population. Other clinical outcomes, including stroke, bleeding (type 2-4), major vascular complications, acute kidney injury (stage 2-4) and permanent pacemaker implantation, were comparable between the two groups. Multivariable logistic regression analysis did not show MAVD to be an independent negative predictor of device success. At one year, survival was similar between patients with MAVD and those with PAS.

Conclusion

For the bicuspid valve, patients with MAVD had a more challenging anatomy. MAVD patients associated with comparable 30-day clinical outcomes after TAVR compared to PAS patients in patients with BAV.

Personalised Treatment in Aortic Stenosis: A Patient-Tailored Transcatheter Aortic Valve Implantation Approach

Transcatheter aortic valve replacement (TAVI) has become a game changer in the management of severe aortic stenosis shifting the concept from inoperable or high-risk patients to intermediate or low surgical-risk individuals. Among devices available nowadays, there is no clear evidence that one device is better than the other or that one device is suitable for all patients. The selection of the optimal TAVI valve for every patient represents a challenging process for clinicians, given a large number of currently available devices. Consequently, understanding the advantages and disadvantages of each valve and personalising the valve selection based on patient-specific clinical and anatomical characteristics is paramount. This review article aims to both analyse the available devices in the presence of specific clinical and anatomic features and offer guidance to select the most suitable valve for a given patient.

A Novel Two-Dimensional Echocardiography Method to Objectively Quantify Aortic Valve Calcium and Predict Aortic Stenosis Severity

Aortic valve calcium (AVC) is a strong predictor of aortic stenosis (AS) severity and is typically calculated by multidetector computed tomography (MDCT). We propose a novel method using pixel density quantification software to objectively quantify AVC by two-dimensional (2D) transthoracic echocardiography (TTE) and distinguish severe from non-severe AS. A total of 90 patients (mean age 76 ± 10 years, 75% male, mean AV gradient 32 ± 11 mmHg, peak AV velocity 3.6 ± 0.6 m/s, AV area (AVA) 1.0 ± 0.3 cm², dimensionless index (DI) 0.27 ± 0.08) with suspected severe aortic stenosis undergoing 2D echocardiography were retrospectively evaluated. Parasternal short axis aortic valve views were used to calculate a gain-independent ratio between the average pixel density of the entire aortic valve in short axis at end diastole and the average pixel density of the aortic annulus in short axis (2D-AVC ratio). The 2D-AVC ratio was compared to echocardiographic hemodynamic parameters associated with AS, MDCT AVC quantification, and expert reader interpretation of AS severity based on echocardiographic AVC interpretation. The 2D-AVC ratio exhibited strong correlations with mean AV gradient (r = 0.72, p < 0.001), peak AV velocity (r = 0.74, p < 0.001), AVC quantified by MDCT (r = 0.71, p <0.001) and excellent accuracy in distinguishing severe from non-severe AS (area under the curve = 0.93). Conversely, expert reader interpretation of AS severity based on echocardiographic AVC was not significantly related to AV mean gradient (t = 0.23, p = 0.64), AVA (t = 2.94, p = 0.11), peak velocity (t = 0.59, p = 0.46), or DI (t = 0.02, p = 0.89). In conclusion, these data suggest that the 2D-AVC ratio may be a complementary method for AS severity adjudication that is readily quantifiable at time of TTE.

Should We Quantify Valvular Calcifications on Cardiac CT in Patients with Infective Endocarditis?

BACKGROUND

Evaluate the impact of valvular calcifications measured on cardiac computed tomography (CCT) in patients with infective endocarditis (IE).

METHODS

Seventy patients with native IE (36 aortic IE, 31 mitral IE, 3 bivalvular IE) were included and explored with CCT between January 2016 and April 2018. Mitral and aortic valvular calcium score (VCS) were measured on unenhanced calcium scoring images, and correlated with clinical, surgical data, and 1-year death rate.

RESULTS

VCS of patients with mitral IE and no peripheral embolism was higher than those with peripheral embolism (868 (25-1725) vs. 6 (0-95), p < 0.05). Patients with high calcified mitral IE (mitral VCS > 100; n = 15) had a lower rate of surgery (40.0% vs.78.9%; p = 0.03) and a higher 1-year-death risk (53.3% vs. 10.5%, p = 0.04; OR = 8.5 (2.75-16.40) than patients with low mitral VCS (n = 19). Patients with aortic IE and high aortic calcifications (aortic VCS > 100; n = 18) present more frequently atypical bacteria on blood cultures (33.3% vs. 4.8%; p = 0.03) than patients with low aortic VCS (n = 21).

CONCLUSION

The amount of valvular calcifications on CT was associated with embolism risk, rate of surgery and 1-year risk of death in patients with mitral IE, and germ's type in aortic IE raising the question of their systematic quantification in native IE.

Surgical management of misdeployed transcatheter aortic valve due to eccentric leaflet calcification

A serious complication of transcatheter valves is the mechanistic failure of the deployment system and prosthesis migration. We report the case of a transcatheter aortic valve implantation which failed during implantation resulting in dislodgement of the prosthesis. Emergency surgery to retrieve the deployment system and surgically replace the native valve was the only option to salvage the patient.

Paravalvular leak prediction after transcatheter aortic valve replacement with self-expandable prosthesis based on quantitative aortic calcification analysis

Background

Paravalvular leak (PVL) is one of the most common complications of transcatheter aortic valve replacement (TAVR) and affects short- and long-term outcomes. The aim of this study was to identify the computed tomography (CT) imaging biomarkers that allow PVL after TAVR to be predicted.

Methods

Patients were included who had severe aortic valve stenosis, had undergone TAVR with a self-expanding valve, and had undergone a pre-procedural CT scan. Data on baseline characteristics, procedural and long-term outcomes were collected retrospectively. We used MATLAB software with a self-developed algorithm for CT scan analysis and found parameters that quantified aortic valve calcifications (AVC) in detail.

Results

Fifty patients were included. The identified CT-derived parameters included AVC size, volume, thickness and density, as well as calcium radial distribution. The volume of the largest calcium block, calcium perimeter and calcium size (assessed by Feret's diameter) showed a strong association with PVL occurrence after TAVR (P=0.012, P=0.001 and P=0.045, respectively). The prognostic model showed that a 10 mm² increase in the local AVC amount in each valve section was associated with a 9.8% (95% CI: 2-18%; P=0.019) increase in the risk of PVL occurrence in the corresponding area after TAVR. ROC analysis revealed that the cut-off point of the AVC area was 96.5 mm² in the polar coordinate system presentation. Kaplan-Meier curves showed worse PVL-free survival in patients with more than 96.5 mm² of calcium area (P=0.013; log-rank).

Conclusions

Quantitative AVC assessment for PVL prediction may play an important role in screening before TAVR. In future, the use of quantitative AVC assessment as an imaging biomarker in TAVR candidates and the creation and extension of an online database containing quantitative AVC parameters may help to identify high PVL risk patients.

Does Aortic Valve Calcium Score Still Predict Death, Cardiovascular Outcomes, and Conductive Disturbances after Transcatheter Aortic Valve Replacement with New-Generation Prostheses?

Background

The development of transcatheter aortic valve replacement (TAVR) has led to an improvement in morbidity-mortality in the treatment of severe aortic stenosis in patients at high surgical risk. However, the procedure is not free from life-threatening cardiovascular outcomes and conductive disturbances. The objective of our study was to analyze the prognostic impact of aortic valve calcium score on the occurrence of complications following the procedure.

Materials and Methods

Patients who have benefited from TAVR with the implantation of new-generation Sapien 3 and Evolut R aortic valve prostheses between January 2017 and July 2018 with the prior realization of a cardiac computed tomography with measurement of the aortic valve calcium score were retrospectively analyzed. Primary endpoint was a composite of death, stroke, and myocardial infarction within a period of 1 month after TAVR. Relation between valvular calcium and conductive disturbances was secondarily analyzed over the same period, and occurrences of high-degree atrioventricular block (paroxysmal or permanent), new-onset left bundle branch block, and the need for permanent or transient cardiac stimulation were associated with the secondary endpoint.

Results

Overall, 144 patients were included. The aortic valve calcium score was not significantly higher in patients who reached the primary endpoint (2936 ± 1235 vs. 3051 ± 1440, P = 0.93). Among the 106 patients analyzed after excluding subjects with a prior pacemaker or left bundle branch block, aortic valvular calcium score was not statistically associated with the occurrence of conduction disturbances (3210 ± 1436 vs. 2948 ± 1223, P = 0.31).

Conclusion

Our results suggest that the measurement of aortic valve calcium score has no prognostic value regarding mortality, cardiovascular events, or conductive disturbances after TAVR using the new generation of valves.

Multidetector computed tomography in transcatheter aortic valve replacement: an update on technological developments and clinical applications

INTRODUCTION

Transcatheter aortic valve replacement (TAVR) has revolutionized the treatment of patients with underlying sever aortic valve stenosis across all spectrum of the disease. CT imaging is so crucial to the pre procedural planning, to incorporate the information from the CT imaging in the decision making intraprocedurally and to predict and identity the post procedural complications.Areas covered: In this article, we review available studies on CT role in TAVR procedure and provide update on the technological developments and clinical applications.Expert opinion: CT imaging, with its high resolution, and in particular its utilization in aortic annular measurements, bicuspid aortic valve assessment, hypoattenuated leaflet thickening and valve in valve therapy proved to be the ideal approach to study the mechanisms of aortic stenosis, detection of high-risk anatomy, more accurate risk stratification and thus to allow a personalized catheter based intervention of the affected patients.