Risk factors for paravalvular leak after transcatheter aortic valve implantation

Open-Heart Cardio-Thoracic Biological Valve Replacement Following Complicated Transcatheter Aortic Valve Implantation

Transcatheter aortic valve implantation (TAVI) is currently becoming the method of choice in high-risk patients with severe aortic valve stenosis. Post-TAVI complications are more common owing to the increasing use of the method. The majority of TAVI complications derive from concomitant aortic stenosis with moderate/severe aortic insufficiency, paravalvular leak, and atrioventricular block. The contemporary TAVI qualification process includes a thorough echocardiography and angio-CT of the aorta, which is crucial in assessing valve measurements, determining the position of the coronary arteries branching from the aorta, and choosing the optimal valve size. We present the case report of an 81-year-old patient admitted to our hospital because of exacerbation of the clinical condition and development of pulmonary edema a few days after TAVI. Despite the reduction of the initial leak, an echocardiographic examination revealed the remaining severe paravalvular aortic leakage. We performed open-heart cardio-thoracic surgery, explanted the TAVI valve, and implanted the biological prosthesis (Edwards Perimount Magna size 25). Introduction of new interventional treatment approaches and the availability of imaging tools have substantially reduced the incidence of significant paravalvular leak and offered a better prognosis for patients undergoing TAVI.

Impact of observer experience on multi-detector computed tomography aortic valve morphology assessment and valve size selection for transcatheter aortic valve replacement

Transcatheter aortic valve replacement (TAVR) has become the standard treatment for aortic stenosis in older patients. It increasingly relies on accurate pre-procedural planning using multidetector computed tomography (MDCT). Since little is known about the required competence levels for MDCT analyses, we comprehensively assessed MDCT TAVR planning reproducibility and accuracy with regard to valve selection in various healthcare workers. 20 randomly selected MDCT of TAVR patients were analyzed using dedicated software by healthcare professionals with varying backgrounds and experience (two structural interventionalists, one imaging specialist, one cardiac surgeon, one general physician, and one medical student). Following the analysis, the most appropriate Edwards SAPIEN 3™ and Medtronic CoreValve valve size was selected. Intra- and inter-observer variability were assessed. The first structural interventionalist was considered as reference standard for inter-observer comparison. Excellent intra- and inter-observer variability was found for the entire group in regard to the MDCT measurements. The best intra-observer agreement and reproducibility were found for the structural interventionalist, while the medical student had the lowest reproducibility. The highest inter-observer agreement was between both structural interventionalists, followed by the imaging specialist. As to valve size selection, the structural interventionalist showed the highest intra-observer reproducibility, independent of the brand of valve used. Compared to the reference structural interventionalist, the second structural interventionalist showed the highest inter-observer agreement for valve size selection [ICC 0.984, 95% CI 0.969-0.991] followed by the cardiac surgeon [ICC 0.947, 95%CI 0.900-0.972]. The lowest inter-observer agreement was found for the medical student [ICC 0.507, 95%CI 0.067-0.739]. While current state-of-the-art MDCT analysis software provides excellent reproducibility for anatomical measurements, the highest levels of confidence in terms of valve size selection were achieved by the performing interventional physicians. This was most likely attributable to observer experience.

The application of 3D printing in preoperative planning for transcatheter aortic valve replacement: a systematic review

BACKGROUND

Recently, transcatheter aortic valve replacement (TAVR) has been suggested as a less invasive treatment compared to surgical aortic valve replacement, for patients with severe aortic stenosis. Despite the attention, persisting evidence suggests that several procedural complications are more prevalent with the transcatheter approach. Consequently, a systematic review was undertaken to evaluate the application of three-dimensional (3D) printing in preoperative planning for TAVR, as a means of predicting and subsequently, reducing the incidence of adverse events.

METHODS

MEDLINE, Web of Science and Embase were searched to identify studies that utilised patient-specific 3D printed models to predict or mitigate the risk of procedural complications.

RESULTS

13 of 219 papers met the inclusion criteria of this review. The eligible studies have shown that 3D printing has most commonly been used to predict the occurrence and severity of paravalvular regurgitation, with relatively high accuracy. Studies have also explored the usefulness of 3D printed anatomical models in reducing the incidence of coronary artery obstruction, new-onset conduction disturbance and aortic annular rapture.

CONCLUSION

Patient-specific 3D models can be used in pre-procedural planning for challenging cases, to help deliver personalised treatment. However, the application of 3D printing is not recommended for routine clinical practice, due to practicality issues.

3-Dimensional printing to predict paravalvular regurgitation after transcatheter aortic valve replacement

BACKGROUND

There is no effective method to predict paravalvular regurgitation prior to transcatheter aortic valve replacement (TAVR).

METHODS

We retrospectively analyzed pre-TAVR computed tomography (CT) scans of 20 patients who underwent TAVR for severe, calcific aortic stenosis and subsequently printed 3-dimensional (3D) aortic root models of each patient. Models were printed using Ninjaflex thermoplastic polyurethane (TPU) (Ninjatek Manheim, PA) and TPU 95A (Ultimaker, Netherlands) on Ultimaker 3 Extended 3D printer (Ultimaker, Netherlands). The models were implanted at nominal pressure with same sized Sapien balloon-expandable frames (Edwards Lifesciences, CA) as received in-vivo. Ex-vivo implanted TAVR models (eTAVR) were scanned using Siemens SOMATOM flash dual source CT (Siemens, Malvern, PA) and then analyzed with Mimics software (Materialize NV, Leuven, Belgium) to evaluate relative stent appositions. eTAVR were then compared to post-TAVR echocardiograms for each patient to assess for correlations of identified and predicted paravalvular leak (PVL) locations.

RESULTS

A total of 20 patients (70% male) were included in this study. The median age was 77.5 (74-83.5) years. Ten patients were characterized to elicit mild (9/10) or moderate (1/10) PVL, and 10 patients presented no PVL. In patients with echocardiographic PVL, eTAVR 3D model analyses correctly identified the site of PVL in 8/10 cases. In patients without echocardiographic PVL, eTAVR 3D model analyses correctly predicted the lack of PVL in 9/10 cases.

CONCLUSION

3D printing may help predict the potential locations of associated PVL post-TAVR, which may have implications for optimizing valve selection and sizing.

Prognostic Model of Typical Complications Caused by Transcatheter Aortic Valve Replacement

The aim of the study was to develop a prognostic model based on statistical discriminant analysis to assess the risk of postoperative disturbance of cardiac conduction and paraprosthetic regurgitation after transcatheter aortic valve replacement.

Materials and Methods

Clinical data of 10 patients implanted with CoreValve^TM prostheses (Medtronic Inc., USA) were used to develop prognostic models. To that end, we analyzed changes in hemodynamic and functional parameters provided by echocardiography in the pre- and postoperative periods.

Results

We observed significant positive changes in the severity of left ventricular myocardial hypertrophy; on the contrary, volume indicators did not significantly change, which might be associated with the concentric type of left ventricular hypertrophy. The discriminant analysis made it possible to determine major (preoperative) morphological and functional indicators associated with the two most common complications of the procedure: left bundle branch block and paraprosthetic regurgitation. Left ventricular posterior wall thickness, interventricular septal thickness, left atrium dimension, and myocardial mass are the critical factors that determine the development of these complications.

Conclusion

In the prognostic model, the proposed weighting coefficients allow one to assess the risk of postoperative complications; however, the presence of false-positive results requires further refinement of these coefficients within the linear equation.

Plugging Paravalvular Leak in Transcatheter Aortic Valves

Paravalvular leak can complicate transcatheter aortic valve replacement with important prognostic implications. Correction of defects requires complex planning and execution. Multiple or irregular lesions, calcified annulus, and high sealing skirts on self-expandable devices are especially challenging. Such defects may be approximated using malleable vascular closure devices. (Level of Difficulty: Intermediate.)