Paravalvular Regurgitation after Transcatheter Aortic Valve Replacement: Comparing Transthoracic versus Transesophageal Echocardiographic Guidance

Paravalvular regurgitation after transcatheter aortic valve replacement: incidence, quantification, and prognostic impact

Transcatheter aortic valve replacement (TAVR) is the standard of care in aortic stenosis with results comparable to surgical aortic valve replacement. However, paravalvular regurgitation (PVR) is more common after TAVR. With the alteration of devices and implantation techniques, the incidence of moderate or more PVR has declined. Mild PVR is still common in around 30% of TAVR patients in low-risk trials. Progression of AS causes myocardial hypertrophy and varying degrees of diastolic dysfunction which may cause heart failure even in combination with small volumes of PVR. Any degree of PVR is associated with an increased risk of overall and cardiovascular mortality. Predictors of PVR are annular eccentricity, severe calcification of the aortic valve, bicuspid aortic valves, and type of prosthesis where balloon-expandable devices are associated with less PVR. PVR is diagnosed using echocardiography, aortic angiogram with or without videodensitometry, haemodynamic parameters, or cardiac magnetic resonance. PVR can be treated using post-dilation, interventional treatment using a vascular plug, or implantation of a second device. Successful post-dilation depends on balloon size which should at least be equal to or >95% of the mean annulus diameter. Implantation of a second device to reduce PVR is successful in ∼90% of cases, either through lengthening of the sealing skirt in case of inadequate position or through further expansion of the index device. Implantation of a vascular plug can successfully reduce PVR and reduce mortality.

Comparison of Intracardiac Echocardiography Versus Transesophageal Echocardiography for Guidance During Transcatheter Aortic Valve Replacement

BACKGROUND AND OBJECTIVES

Evidence regarding the efficacy and safety of intracardiac echocardiography (ICE) for guidance during transcatheter aortic valve replacement (TAVR) is limited. This study aimed to compare the clinical efficacy and safety of ICE versus transesophageal echocardiography (TEE) for guiding TAVR.

METHODS

This prospective cohort study included patients who underwent TAVR from August 18, 2015, to June 31, 2021. Eligible patients were stratified by echocardiographic modality (ICE or TEE) and anesthesia mode (monitored anesthesia care [MAC] or general anesthesia [GA]). Primary outcome was the 1-year composite of all-cause mortality, rehospitalization for cardiovascular cause, or stroke, according to the Valve Academic Research Consortium-3 (VARC-3) definition. Propensity score matching was performed, and study outcomes were analyzed for the matched cohorts.

RESULTS

Of the 359 eligible patients, 120 patients were matched for the ICE-MAC and TEE-GA groups, respectively. The incidence of primary outcome was similar between matched groups (18.3% vs. 20.0%; adjusted hazard ratio, 0.94; 95% confidence interval [CI], 0.53-1.68; p=0.843). ICE-MAC and TEE-GA also had similar incidences of moderate-to-severe paravalvular regurgitation (PVR) (4.2% vs. 5.0%; adjusted odds ratio, 0.83; 95% CI, 0.23-2.82; p=0.758), new permanent pacemaker implantation, and VARC-3 types 2-4 bleeding.

CONCLUSIONS

ICE was comparable to TEE for guidance during TAVR for the composite clinical efficacy outcome, with similar incidences of moderate-to-severe PVR, new permanent pacemaker implantation, and major bleeding. These results suggest that ICE could be a safe and effective alternative echocardiographic modality to TEE for guiding TAVR.

Evolution of interventional imaging in structural heart disease

Treatments for structural heart diseases (SHD) have been considerably evolved by the widespread of transcatheter approach in the last decades. The progression of transcatheter treatments for SHD was feasible due to the improvement of devices and the advances in imaging techniques. In this setting, the cardiovascular imaging is pivotal not only for the diagnosis but even for the treatment of SHD. With the aim of fulfilling these tasks, a multimodality imaging approach with new imaging tools for pre-procedural planning, intra-procedural guidance, and follow-up of SHD was developed. This review will describe the current state-of-the-art imaging techniques for the most common percutaneous interventions as well as the new imaging tools. The imaging approaches will be addressed describing the use in pre-procedural planning, intra-procedural guidance, and follow-up.

Minimalist transcatheter aortic valve replacement misses paravalvular regurgitation: Incidence and echocardiographic distribution of missed paravalvular regurgitation

BACKGROUND

Paravalvular regurgitation (PVR) may be missed intraoperatively with transthoracic echocardiography (TTE) guided minimalist TAVR. We sought to determine the incidence and echocardiographic distribution of PVR missed on intra-op TTE, but detected on predischarge TTE.

METHODS

From July 2015 to 2020, 475 patients with symptomatic severe native aortic stenosis underwent TTE-guided minimalist TAVR. Missed PVR was defined as predischarge PVR that was ≥1 grade higher than the corresponding intra-op PVR severity. PVR was classified as anterior or posterior on the four standard TTE views; parasternal short-axis (PSAX), parasternal long-axis (PLAX), apical 3-chamber (A3C), and 5-chamber (A5C). Location-specific risk of missed PVR was then determined.

RESULTS

Mild or greater PVR was seen in 55 (11.5%) cases intra-op and 91 (19.1%) at predischarge, with no severe PVR. Among the 91 patients with ≥mild predischarge PVR, missed PVR was present in 42 (46.2%). Compared to the corresponding anterior jets, missed PVR rate was significantly higher for posterior jets in PLAX (62.5% vs. 25.0%, p = 0.005), A5C (56.9% vs. 25.0%, p = 0.009), PSAX (66.7% vs. 24.3%, 0.001), but not A3C (58.5% vs. 40.0%, p = 0.28).

CONCLUSIONS

Intraoperative TTE-guided minimalist TAVR either misses nearly half of ≥mild PVR or underestimates PVR by ≥1 grade when compared to predischarge TTE. Posterior PVR jets are more likely to be missed. Transesophageal echo guidance may help minimize missing PVR. Further studies are warranted.

Comparison of Radiation Exposure Among Interventional Echocardiographers, Interventional Cardiologists, and Sonographers During Percutaneous Structural Heart Interventions

Importance

Transesophageal echocardiography during percutaneous left atrial appendage closure (LAAO) and transcatheter edge-to-edge mitral valve repair (TEER) require an interventional echocardiographer to stand near the radiation source and patient, the primary source of scatter radiation. Despite previous work demonstrating high radiation exposure for interventional cardiologists performing percutaneous coronary and structural heart interventions, similar data for interventional echocardiographers are lacking.

Objective

To assess whether interventional echocardiographers are exposed to greater radiation doses than interventional cardiologists and sonographers during structural heart procedures.

Design, Setting, and Participants

In this single-center cross-sectional study, radiation doses were collected from interventional echocardiographers, interventional cardiologists, and sonographers at a quaternary care center during 30 sequential LAAO and 30 sequential TEER procedures from July 1, 2016, to January 31, 2018. Participants and study personnel were blinded to radiation doses through data analysis (January 1, 2020, to October 12, 2021).

Exposures

Occupation defined as interventional echocardiographers, interventional cardiologists, and sonographers.

Main Outcomes and Measures

Measured personal dose equivalents per case were recorded using real-time radiation dosimeters.

Results

A total of 60 (30 TEER and 30 LAAO) procedures were performed in 60 patients (mean [SD] age, 79 [8] years; 32 [53.3%] male) with a high cardiovascular risk factor burden. The median radiation dose per case was higher for interventional echocardiographers (10.6 μSv; IQR, 4.2-22.4 μSv) than for interventional cardiologists (2.1 μSv; IQR, 0.2-8.3 μSv; P < .001). During TEER, interventional echocardiographers received a median radiation dose of 10.5 μSv (IQR, 3.1-20.5 μSv), which was higher than the median radiation dose received by interventional cardiologists (0.9 μSv; IQR, 0.1-12.2 μSv; P < .001). During LAAO procedures, the median radiation dose was 10.6 μSv (IQR, 5.8-24.1 μSv) among interventional echocardiographers and 3.5 (IQR, 1.3-6.3 μSv) among interventional cardiologists (P < .001). Compared with interventional echocardiographers, sonographers exhibited low median radiation doses during both LAAO (0.2 μSv; IQR, 0.0-1.6 μSv; P < .001) and TEER (0.0 μSv; IQR, 0.0-0.1 μSv; P < .001).

Conclusions and Relevance

In this cross-sectional study, interventional echocardiographers were exposed to higher radiation doses than interventional cardiologists during LAAO and TEER procedures, whereas sonographers demonstrated comparatively lower radiation doses. Higher radiation doses indicate a previously underappreciated occupational risk faced by interventional echocardiographers, which has implications for the rapidly expanding structural heart team.

Effect of eliminating pre-discharge transthoracic echocardiogram on outcomes after TAVR

OBJECTIVES

The aim of this study was to determine the safety of eliminating the pre-discharge transthoracic echocardiogram (TTE) on 30-day outcomes in patients undergoing transcatheter aortic valve replacement (TAVR).

BACKGROUND

TTE is utilized before, during, and after TAVR. Post-procedural, pre-discharge TTE assists in assessment of prosthesis function and detection of clinically significant paravalvular leak (PVL) after TAVR.

METHODS

Patients who underwent TAVR at Mayo Clinic from July 2018 to July 2019 were included in a prospective institutional registry. Patients undergoing TAVR prior to February 2019 received a pre-discharge TTE, while those undergoing TAVR after February 2019 did not. Both cohorts were evaluated with TTE at 30 days post-TAVR.

RESULTS

A total of 330 consecutive patients were included. Of these, 160 patients (age 81.1 ± 7.6) had routine pre-discharge TTE, while 170 patients (age 78.9 ± 7.5) were dismissed without routine pre-discharge TTE. Mortality at 30 days was similar between the two groups (0% and 1.2%, respectively). One episode of PVL requiring intervention (0.6%) occurred in the pre-discharge TTE group and none in the group without pre-discharge TTE at 30-day follow-up. There was a similar incidence of total composite primary and secondary adverse events between the cohort receiving a pre-discharge TTE and those without (28.1% vs. 25.3%, P = 0.56) at 30 days. The most common event was need for permanent pacemaker or ICD implantation in both groups (13.1% vs. 11.8%, P = 0.71).

CONCLUSIONS

Elimination of the pre-discharge TTE is safe and associated with comparable 30-day outcomes to routine pre-discharge TTE. These findings have implication for TAVR practice cost-efficiency and health care utilization.

Utilization, Costs, and Outcomes of Conscious Sedation Versus General Anesthesia for Transcatheter Aortic Valve Replacement

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Technical and clinical study of x-ray-based surface echo probe tracking using an attached fiducial apparatus

PURPOSE

Several types of structural heart intervention (SHI) use information from multiple imaging modalities to complete an interventional task. For example, in transcatheter aortic valve replacement (TAVR), placement and deployment of a bioprosthetic aortic valve in the aorta is primarily guided by x-ray fluoroscopy (XRF), and echocardiography provides visualization of cardiac anatomy and blood flow. However, simultaneous interpretation of independent x-ray and echo displays remains a challenge for the interventionalist. The purpose of this work was to develop a novel echo/x-ray co-registration solution in which volumetric transthoracic echo (TTE) is transformed to the x-ray coordinate system by tracking the three-dimensional (3D) pose of a probe fiducial attachment from its appearance in two-dimensional (2D) x-ray images.

METHODS

A fiducial attachment for a commercial TTE probe consisting of rings of high-contrast ball bearings was designed and fabricated. The 3D pose (position and orientation) of the fiducial attachment is estimated from a 2D x-ray image using an algorithm in which a virtual point cloud model of the attachment is iteratively rotated, translated, and forward-projected onto the image until the average sum-of-squares of grayscale values at the projected points is minimized. Fiducial registration error (FRE) and target registration error (TRE) of this approach were evaluated in phantom studies using TAVR-relevant gantry orientations and four standard acoustic windows for the TTE probe. A patient study was conducted to assess the clinical suitability of the fiducial attachment prototype during TTE imaging of patients undergoing SHI. TTE image quality for the task of guiding a transcatheter procedure was evaluated in a reviewer study.

RESULTS

The 3D FRE ranged from 0.32 ± 0.03 mm (mean ± SD) to 1.31 ± 0.05 mm, depending on C-arm orientation and probe acoustic window. The 3D TRE ranged from 1.06 ± 0.03 mm to 2.42 ± 0.06 mm. Fiducial pose estimation was stable when >75% of the fiducial markers were visible in the x-ray image. A panel of reviewers graded the presentation of heart valves in TTE images from 48 SHI patients. While valve presentation did not differ significantly between acoustic windows (P > 0.05), the mitral valve did achieve a significantly higher image quality compared to the aortic and tricuspid valves (P < 0.001). Overall, reviewers perceived sufficient image quality in 76.5% of images of the mitral valve, 54.9% of images of the aortic valve, and 48.6% of images of the tricuspid valve.

CONCLUSIONS

Fiducial-based tracking of a commercial TTE probe is compatible with clinical SHI workflows and yields 3D target registration error of less than 2.5 mm for a variety of x-ray gantry geometries and echo probe acoustic windows. Although TTE image quality with respect to target valve anatomy was sufficient for the majority of cases examined, prescreening of patients for sufficient TTE quality would be helpful.

Effect of a fourth-generation transcatheter valve enhanced skirt on paravalvular leak

OBJECTIVES

The aim of this study was to assess the 30 day incidence of paravalvular leak (PVL) and need for aortic valve reintervention of a fourth generation balloon expandable transcatheter valve with enhanced skirt (4G-BEV) (SAPIEN 3 Ultra) compared with a third generation balloon expandable transcatheter valve (3G-BEV) (SAPIEN 3).

BACKGROUND

The incidence of PVL has steadily declined with iterative improvements in transcatheter aortic valve replacement (TAVR) technology and implantation strategies.

METHODS

Patients who underwent TAVR at Mayo Clinic from 7/2018 to 7/2019 were included in a prospective institutional registry. 4G-BEV has been utilized since 2/2019, and, after this date, 3G-BEV and 4G-BEV were simultaneously used. 4G-BEV had three sizes (20, 23, and 26 mm) while 3G-BEV included four sizes (20, 23, 26, and 29 mm). Both cohorts were evaluated at 30 days post-TAVR with a transthoracic echocardiogram to assess for PVL.

RESULTS

A total of 260 consecutive patients were included. Of these, 101 patients received a 4G-BEV and 159 patients received a 3G-BEV. There were more females (p = .0005) and a lower aortic valve calcium score (p = .02) in the 4G-BEV cohort at baseline. Age, STS risk score, NYHA Class, and aortic valve mean gradient did not differ between groups. 4G-BEV was associated with a lower incidence of mild PVL (10.8 vs. 36.5%; p < .0001) and moderate PVL (0 vs. 5.8%) compared to the 3G-BEV at 30 days. There was no association between PVL and valve size in either cohort.

CONCLUSIONS

Utilization of 4G-BEV is associated with reduced PVL at 30 days post-TAVR compared with 3G-BEV.

Efficiency, Safety, and Quality of Life After Transcatheter Aortic Valve Implantation Performed With Moderate Sedation Versus General Anesthesia

There is growing interest in "minimalist" transcatheter aortic valve implantation (M-TAVI), performed with conscious sedation instead of general anesthesia (GA-TAVI). We assessed the impact of M-TAVI on procedural efficiency, long-term safety, and quality of life (QoL) in 477 patients with severe aortic stenosis (82 years, women 50%, STS 5.0), who underwent M-TAVI (n = 278) or GA-TAVI (n = 199). M-TAVI patients were less likely to have NYHA Class ≥3, valve-in-valve TAVI, and receive self-expanding valves. M-TAVI was completed without conversion to GA in 269 (97%) patients. M-TAVI was more efficient that GA-TAVI including shorter lengths of stay (2 vs 3 days, p <0.0001), higher likelihood of being discharged home (87% vs 72%, p <0.0001), less use of blood transfusions (10% vs 22%, p = 0.0008), inotropes (13% vs 32%, p <0.0001), contrast volume (50 vs 90 ml, p <0.0001), fluoroscopy time (20 vs 24 minute, p <0.0001), and need for >1 valves (0.4 vs 5.5%, p = 0.0004). At 1-month, death/stroke (M-TAVI vs GA-TAVI 4.0 vs 6.5%) and a "safety composite" end point (death, stroke, transient ischemic attack, myocardial infarction, new dialysis, major vascular complication, major or life-threatening bleeding, and new pacemaker: 17.6% vs 21.1%) were similar (p = NS for both). At a median follow-up of 365 days, survival curves showed similar incidence of death/stroke as well as the safety composite end point between the groups. QoL scores were similar at baseline and 1-month after TAVI. In multivariable analyses, M-TAVI showed significant improvements in all parameters of procedural efficiency. In conclusion, M-TAVI is more efficient than GA-TAVI, with similar safety at 1-month and long-term, and similar QoL scores at 1 month.

Recent Developments in Catheter-Based Cardiac Procedures

New developments in transcatheter valve technologies including aortic valve replacement and mitral valve and tricuspid valve interventions are described. Recent studies evaluating the success rate, patient outcomes, and anesthesiologic management of the procedures are discussed.

Difficult TEE Probe Placement: The Evidence, Troubleshooting Techniques, and a Guide to Alternative Monitoring Options for Intraoperative Physicians

Transesophageal echocardiography (TEE) imaging has become an essential component of many open and interventional cardiac procedures and has increasing use in monitoring for noncardiac procedures, partly because of an aging population. Whether expected or not, encountering difficulty when inserting the TEE probe presents the anesthesiologist with a conundrum. Repeated insertion attempts increase the risk of a serious complication; however, proceeding without TEE may be unacceptable to the proceduralist or surgeon. The aim of this review is to present the spectrum of complications possible with TEE, propose several evidence-based insertion tips, examine potential alternative cardiac imaging options, and finally, propose a roadmap for providers who encounter difficulty when placing a TEE probe.

Simplification and optimization of transcatheter aortic valve implantation - fast-track course without compromising safety and efficacy

Transcatheter aortic valve implantation (TAVI) has become an established therapeutic option for patients with symptomatic, severe aortic valve stenosis. Ageing of the Western and Asian population and expansion of indications for TAVI will lead to a substantial increase in the number of TAVI procedures performed worldwide within the next decades. In line with the maturation of TAVI over the past few years, there has also been a significant simplification and optimisation of the TAVI procedure. A minimalist TAVI procedure and fast-track TAVI course have been shown to have distinct advantages over the more traditional TAVI approach. The aim of this manuscript is to discuss strategies of TAVI simplification and optimization, with special focus on fast-track TAVI, without compromising safety and efficacy.

Outcomes and Safety of Transcatheter Aortic Valve Implantation With and Without Routine Use of Transesophageal Echocardiography

Transesophageal echocardiography (TEE) has been extensively used historically for Transcatheter aortic valve implantation (TAVI) but focus is shifting from routine use of TEE and general anesthesia to "as needed" use. We evaluated patients who had TAVI in our institution from September 2012 to February 2017. Decision for implantation and use of TEE during procedure was made by the structural heart team on a case-to-case basis, based on FDA approved indications. Data including procedural details, length of stay and rehospitalizations were obtained from all patients. TAVI was performed on 178 patients during the study period of which 104 of 178 had TEE during TAVI. Baseline characteristics were fairly comparable in both groups. Similar proportion of self-expanding and balloon expanding valves were deployed. Patients in TEE group had longer overall procedure time (107 minute vs 83 minute, p = 0.0002) and longer length of stay (5.01days vs 2.49days, p < 0.0001). Echocardiographic study postprocedure showed similar incidence of paravalvular leak and similar gradients and velocities across aortic valve. Rates of 30-day readmissions were similar in both groups. In conclusion, in this single-center retrospective analysis-TAVI without the 'routine use' of TEE was comparable with those done with TEE guidance in terms of periprocedural complications and 30-day readmissions. Overall procedure length and length of stay was predictably higher in the TEE group.

Comparison of general anaesthesia and non-general anaesthesia approach in transfemoral transcatheter aortic valve implantation

Objective

Performing transfemoral transcatheter aortic valve implantation (TAVI) without general anaesthesia (GA) has been increasingly adopted. We sought to study the impact of GA and non-GA approaches on procedural outcome and 30-day and 1-year mortality in transfemoral TAVI.

Methods

The UK TAVI registry holds information for every TAVI procedure in the UK. We analysed the data for patients implanted during 2013–2014 using either an Edwards Sapien or a Medtronic CoreValve prosthesis. Propensity score-matching analysis was performed to adjust for confounding factors.

Results

2243 patients were studied (aged 81.4±7.5 years, 1195 males). 1816 (81%) underwent TAVI with GA and 427 (19%) without GA. Transoesophageal echocardiography (TOE) was used in 92.3% of GA and 12.4% of non-GA cases (p<0.001). There was no significant difference in the rate of successful valve deployment (GA 97.2% vs non-GA 95.7%, p=0.104) and in the incidence of more than mild aortic regurgitation (AR) at the end of the procedure (GA 5.6% vs non-GA 7.0%, p=0.295). However, procedure time was longer (131±60 vs 121±60mins, p=0.002) and length of stay was greater (8.0±13.5 vs 5.7±5.5 days, p<0.001) for GA cases. 30-day and 1-year mortality rates did not differ between the GA and non-GA cases. After propensity matching, these results remained unchanged. A second propensity analysis (adjusted for mode of anaesthesia) did not show an association between use of TOE and rate of successful valve deployment or frequency of significant AR. Neither was TOE associated with a longer procedural time or greater length of stay.

Conclusion

Procedure outcome, and 30-day and 1-year mortality are not influenced by mode of anaesthesia. However, GA is associated with longer procedure duration and greater length of stay.

Transthoracic echocardiography is adequate for intraprocedural guidance of transcatheter aortic valve implantation

Background

While transcatheter aortic valve implantation (TAVI) has traditionally been supported intraprocedurally by transoesophageal echocardiography (TOE), transthoracic echocardiography (TTE) is increasingly being used. We evaluated echocardiographic imaging characteristics and clinical outcomes in patients who underwent TTE during TAVI (TTE-TAVI).

Methods and results

A select team of dedicated sonographers and interventional echocardiographers performed TTE-TAVI in 278 patients, all of whom underwent TAVI through transfemoral access. We implanted the Medtronic EVOLUT R valve in 258 patients (92.8%). TTE images were acquired immediately pre-procedure by a dedicated sonographer in the cardiac catheterization laboratory with the patient in the supine position. TTE was then performed post deployment of TAVI. In the procedure, TTE image quality was fair or better in 249 (89.6%) cases. Color-flow Doppler was adequate or better in 275 (98.9%) cases. In 2 cases, paravalvular regurgitation (PVL) could not be assessed confidently by echocardiography due to poor image quality; in those cases, PVL was assessed by fluoroscopy, aortic root injection and invasive hemodynamics. Both TTE and invasive hemodynamics were used in the assessment of need for post-deployment stent ballooning (n = 23, 8.3%). TTE adequately recognized new pericardial effusion in 3 cases. No case required TOE conversion for image quality. There was only 1 case of intraprocedural TTE failing to recognize moderate PVL, without clinical implication. In 99% of patients, TTE-TAVI adequately assessed PVL compared with 24-h and 1-month follow-up TTE.

Conclusions

With the current generation of TAVI, TTE-TAVI is adequate intraprocedurally when performed by specialized sonographers and dedicated cardiologists in a highly experienced TAVI center.

Role of Echocardiography in Transcatheter Valvular Heart Disease Interventions

PURPOSE OF REVIEW

Transcatheter valvular interventions have increased in importance and utility for surgical valve repair and replacement. Cardiac imaging is the most crucial aspect of procedural planning and guidance. Echocardiography is a widely used, portable, and dynamic imaging modality used for many of these interventions. This review will summarize the role echocardiography in structural heart valvular interventions.

RECENT FINDINGS

Intraprocedural echocardiographic guidance has been a mainstay of structural heart interventions. Over the years, the use of 3-dimensional echocardiography has increased, and studies have shown utility in paravalvular leak prediction in the setting of transcatheter aortic valve replacement, procedural guidance in MitraClip repair, and in mitral and tricuspid valve therapies. Intraprocedural echocardiography is of paramount important for procedural success during all structural heart valvular interventions. Continued use of 2 and 3-dimensional echocardiography will be a major factor in driving the innovative field of structural heart interventions forward.