Generational Differences in Outcomes of Self-Expanding Valves for Transcatheter Aortic Valve Replacement

Abstract

Background. The Medtronic Evolut Pro valve (EPV) is a new-generation self-expanding valve (SEV), particularly designed to reduce paravalvular leak (PVL) rates in transcatheter aortic valve replacement (TAVR). We aimed to compare the safety and efficacy of EPV with older-generation SEVs, in particular, postprocedural PVL and permanent pacemaker (PPM) implantation rates. Methods. We performed a retrospective, multicenter, propensity-matched analysis of the Israeli TAVR registry between September 2008 and June 2019. Two independent propensity score-matched comparisons were performed comparing EPV with the first-generation CoreValve (CV), and comparing EPV with the second-generation Evolut R valve (ERV). Results. The registry included 2591 patients who were propensity-matched into 3 cohorts: EPV (n = 222), CV (n = 212), and ERV (n = 213). Moderate and above PVL rates were lower for EPV (angiographic PVL [aPVL], 0.6%; echocardiographic PVL [ePVL], 3.0%) as compared with CV (aPVL, 7.8% [P<.001] and ePVL, 11.6% [P<.01]), but not as compared with ERV (aPVL, 6.4% [P<.01] and ePVL, 4.4% [P=.57]). Lower rates of PPM were noted for EPV (16.3%) as compared with both CV (33.5%; P<.001) and ERV (24.4%; hazard ratio, 0.61; 95% confidence interval, 0.37-0.995; P=.046). Other safety and efficacy outcome rates were excellent, with significant improvements as compared with older-generation SEVs. Conclusions. The EPV demonstrates excellent procedural safety and efficacy outcomes. Moderate and above PVL rates were significantly reduced in comparison with CV; however, not significantly reduced as compared with ERV. The need for PPM implantation was lower as compared with both older-generation valves.

J INVASIVE CARDIOL 2022;34(4):E326-E333.

Key words: Evolut Pro, permanent pacemaker, PVL, TAVR

Transcatheter aortic valve replacement (TAVR), first introduced for compassionate use in non-operable patients nearly 20 years ago, has become a standard of care for the treatment of aortic stenosis (AS), initially for patients with intermediate to high surgical risk, and currently for low surgical risk patients as well.^1,2

The Medtronic CoreValve (CV) was the first self-expanding valve (SEV) introduced, comparing favorably over both conservative medical treatment and surgical aortic valve replacement.^3,4 The development of low-profile delivery systems and accumulating operator experience and expertise improved outcomes dramatically over the years.^5,6 The second-generation Medtronic Evolut R valve (ERV), developed with the aim of reducing paravalvular leak (PVL), has consistently demonstrated superior results when compared against first-generation valves, with lower PVL rates, need for permanent pacemaker (PPM) implantation and other complications, appropriately increasing survival.^7,8

Nevertheless PVL persists as a major TAVR limitation despite increasing operator experience, improved patient-prosthesis matching, and lower-risk patients undergoing TAVR, and is associated with worse clinical outcomes and increased mortality.^9,10 The third-generation Evolut Pro valve (EPV) has been recently introduced, specifically designed to reduce PVL rate and severity. An external pericardial wrap has been added, designed to increase valve surface area and contact with native anatomy, supposedly improving sealing and reducing PVL.¹¹

Few studies have evaluated the new EPV. While all studies demonstrate excellent outcomes, there have been conflicting results regarding PVL and PPM.^11-14 Our aim was to compare the safety and efficacy of EPV with older-generation SEVs, and in particular, postprocedural PVL and PPM rates.

Methods

Study population. The Israeli national TAVR registry includes patients with symptomatic AS who underwent TAVR between September, 2008 and June, 2019. During the study period, 4334 patients with symptomatic AS underwent TAVR at 4 medical institutions in Israel. We excluded patients for whom valve-type data were missing (n = 202), patients treated with valves produced by other manufacturers, such as Abbott, Boston Scientific, Direct Flow, and Edwards Lifesciences (n = 1534), and patients for whom TAVR was performed via non-femoral artery vascular access (n = 112). After exclusion, a total of 2486 patients treated with Medtronic SEVs remained (1115 CVs, 1149 ERVs, 222 EPVs). We separated the study into 2 cohorts. In the first cohort, we compared outcomes between patients treated with EPV and CV. In the second cohort, we compared outcomes between patients treated with EPV and ERV. Due to the differences in group sizes and baseline characteristics, we used propensity matching to compare groups of similar sizes and similar baseline characteristics. Propensity matching was based on baseline characteristics including gender, age, Society of Thoracic Surgeons (STS) risk score, EuroSCORE-2 risk score, atrial fibrillation, lung disease, and diabetes mellitus. Figure 1 displays a flow diagram detailing study design and exclusion criteria. The study was approved by the institutional review board.

Criteria for study inclusion. The diagnosis of severe symptomatic AS was based on clinical and echocardiographic criteria of symptomatic patients with an aortic valve area (AVA) of ≤1 cm² or an indexed AVA of ≤0.6 cm².¹⁵ Suitability and eligibility for TAVR were assessed by a multidisciplinary cardiology team according to guidelines published at the time of the procedure by the European Society of Cardiology or the American College of Cardiology/American Heart Association. A senior interventional cardiologist was responsible for all procedural aspects including valve selection, which was determined at the operator’s discretion, according to valve availability.

TAVR prostheses. Three types of AV prostheses were included in the study, all designed and manufactured by Medtronic. The CV is a bovine-pericardium tricuspid SEV with a nitinol self-expanding frame. It is available in annular sizes of 26, 29, and 31 mm and navigated through an 18-Fr sheath and requires vessel diameters of at least 6 mm.¹⁶ The ERV is a porcine-pericardium tricuspid SEV, available in annular sizes of 23, 26, 29, and 34 mm. It features an integrated inline sheath with an outer diameter of 14/16 Fr and requires vessel diameters of at least 5 mm. Design modifications include a nitinol design at the annulus that optimizes radial expansive force and a lower prosthesis height with a longer porcine-pericardium sealing skirt with improved sealing dynamics. Due to a sheathless technology in part, the ERV can be navigated through a smaller-diameter delivery system, thus reducing vascular complications. The ERV provides superior positioning accuracy due to its Enveo R delivery system, which allows valve recapturing and repositioning and a 1:1 torque response between deployment knob and the movement of the capsule containing the valve.^12,17

The third generation EPV is a porcine pericardium tricuspid SEV, available in annular sizes of 23, 26, and 29 mm. It is navigated through a 16-Fr sheath and requires vessel diameters of at least 5.5 mm. The EPV is also deployed using the Enveo R delivery system. The main modification consists of an additional external pericardial wrap covering the first 1.5 cells (≈1.2 cm), designed to optimize contact with native anatomy against various annular profiles, allowing better sealing with the aim of reducing PVL.^12,18

Definition of outcome measures. The two primary outcome measures of the study were postprocedural PVL of moderate severity and higher and need for PPM implantation. Secondary outcomes included device success and safety outcomes, defined according to the Valve Academic Research Consortium-2 consensus definitions.¹⁹ Postprocedural echocardiographic evaluations were conducted by specialists and interpreted by senior physicians and measurements as close to 1 month following the procedure were preferred whenever possible. Mortality data were retrieved by identification numbers from the automatically updated Israeli Ministry of the Interior database.

Statistical analysis. Categorical variables were reported as numbers and percentages and compared using Pearson’s Chi test or Fisher’s exact test. Continuous variables were reported as mean ± standard deviation and compared using the independent samples t test or Mann–Whitney test and were tested for normal distribution using the Shapiro-Wilk’s test, histograms, and Q-Q plots. Odds ratios (ORs) and 95% confidence intervals (CIs) were reported for the main study outcome measures. A 2-tailed P-value <.05 was considered to be statistically significant. All statistical analyses were performed with SPSS 2013 Statistics for Windows, version 25.0 (IBM, Inc).

Results

Baseline characteristics for both cohorts prior to propensity-score matching are presented in Table 1. Patients treated with EPV were younger, had lower STS and EuroSCORE 2 scores, had less coronary artery disease, underwent prior percutaneous coronary interventions in greater numbers, and had higher ejection fractions as compared with both CV and ERV groups. CV patients had more lung disease and lower hemoglobin levels. Hypertension, lung disease, prior valve intervention rates, and pressure gradients across the AV were lower for ERV patients as compared with EPV patients. Aortic valve area measurements were not significantly different in both comparisons.

Following propensity matching, 434 patients were compared in the first cohort (212 CVs, 222 EPVs), and 435 in the second cohort (213 ERVs, 222 EPVs), as displayed in Table 2. Patients treated with EPVs had lower STS and EuroSCORE 2 scores, had less coronary artery disease, underwent more prior percutaneous coronary interventions, and had lower systolic pulmonary artery pressure in comparison with both CV and ERV groups. As compared with CV alone, patients treated with EPV were younger, more often female gender, had higher body mass index, and had higher ejection fractions, but had less hypertension. As compared with ERV alone, EPV patients had fewer prior cerebrovascular accidents and underwent more prior coronary artery bypass grafting.

Procedural characteristics and complications are summarized in Table 3. Fluoroscopy times were lower for EPV patients as compared with both ERV and CV groups and contrast volume use was higher in comparison with the CV group. EPV implantation resulted in higher device success rates, as well as lower rates of need for a second valve, tamponade, valve malpositioning, and valve migration or embolization as compared with both older-generation valve groups. Coronary obstruction rates were higher in the ERV group vs the EPV group.

The study’s primary outcomes are displayed in Table 4. Angiographic PVL rates of ≥ moderate severity were lower for patients treated with EPV (0.6%) as compared with both CV (7.8%; OR, 0.07; 95% CI, 0.01-0.51; P<.001) and ERV groups (6.4%; OR, 0.08; 95% CI, 0.01-0.65; P<.01). Echocardiographic PVL rates of ≥ moderate severity for EPV (3.0%) were lower as compared with CV (11.6%; OR, 0.24; 95% CI, 0.09-0.65; P<.01), but not significantly different as compared with ERV (4.4%; OR, 0.68; 95% CI, 0.21-2.20; P=.57). Permanent pacemaker implantation rates were lower for EPV (16.3%) as compared with both CV (33.5%; OR, 0.39; 95% CI, 0.24-0.62; P<.001) and ERV groups (24.4%; OR, 0.61; 95% CI, 0.37-0.995; P=.046).

Notable secondary outcomes are presented in Table 5. Differences include lower rates of acute kidney injury for EPV (8.1%) vs CV (22.0%; P<.001) and vs ERV (16.3%; P=.01), higher postprocedural ejection fraction for EPV (59.8 ± 7.2%) vs CV (54.1 ± 12.4%; P<.001) and vs ERV (56.8 ± 9.8%; P=.01), and lower systolic pulmonary artery pressure for EPV (38.1 ± 12.0 mm Hg) vs CV (42.6 ± 15.3 mm Hg; P=.01) and vs ERV (43.7 ± 15.0 mm Hg; P<.01), and had shorter durations until discharge as compared with both older-generation valves. New left bundle-branch block rates were lower as compared with ERV alone (26.3% vs 38.9%; P=.01) and bleeding of ≥ major severity occurred more frequently only for patients treated with CV (5.0% vs 15.6%; P<.001).

AVB of ≥ second degree occurred in 13.5% of the EPV group (81.3% of new PPM patients), 32.2% of the CV group (69.4% of new PPM patients), and 23.2% of the ERV group (58.2% of new PPM patients). The incidence of left bundle-branch block in new PPM-implanted patients was 43.3% in the EPV group, 47.8% in the ERV group, and 35.7% in the CV group.

Discussion

Our study demonstrated that using novel, third-generation, Evolut Pro SEVs, clinically significant PVL rates were significantly reduced as compared with older generations of Medtronic SEVs as measured by angiography, but only significantly lower than the first-generation CoreValve when measured by echocardiography. EPV implantation was found to reduce PPM rates as compared with both older-generation SEVs. Other efficacy and safety results were excellent and surpassed those achieved using older-generation valves.

In our study, we show that clinically meaningful PVL (ie, of moderate severity and above) is not significantly improved as compared with ERV, as measured by echocardiography, as opposed to angiographic PVL rates measured immediately following implantation. PVL is acknowledged to be the Achilles’ heel of TAVR,^9,10 and its reduction is paramount for TAVR durability as indications expand to younger and healthier populations.^1,2 Prior technological improvements and preprocedural imaging allow better prosthesis matching and positioning, with resultant reduction of PVL incidence and severity. However PVL persists, commonly originating around the annular area,²⁰ and the EPV was specifically designed to reduce PVL rates by superior sealing capability at multiple levels in various annulus shapes.

Forrest et al¹² evaluated the efficacy of the new EPV in a study supported by its manufacturer, Medtronic. They found that when using the EPV, 72% of patients experienced none-trace PVL, with the remainder having mild PVL (28%). The occurrence of no cases of above-mild PVL is extraordinary when compared against previous-generation SEVs and balloon-expandable valves. In our study, we found higher rates of clinically significant PVL as well as PVL rates of mild severity (43.3% per echocardiography). Our results match those reported by Rao et al²¹ and Hellhammer et al,¹¹ who failed to find a statistically significant advantage for EPV when compared with ERV in relatively smaller patient cohorts. Similarly, a study performed by Piayda et al evaluated results specifically in patients with severely calcified AVs, which is known to significantly contribute to PVL,²² and hence a specific target for design modifications in the EPV. Their excellent outcomes were also not significantly superior over ERV. Our study evaluated results of a large cohort of TAVR patients treated with the new EPV and our results support these smaller-scale studies.

Williams et al²³ recently published data demonstrating that PVL rates for EPV may improve over time as 1.7% of patients had moderate PVL immediately following TAVR while none had moderate PVL after 1 year. A study evaluating very long-term outcomes of CV function >5 years after TAVR likewise demonstrated an improvement in PVL rate and severity during a long-term follow-up.²⁴ These results suggest that short-term PVL rates demonstrated in our study should stand the test of time and may even improve.

Forrest et al¹² also reported a PPM implantation rate of 11.8%, which was lower than those reported for older-generation valves in the literature. They hypothesized that although not specifically designed to lower PPM rates, EPV force-distribution modifications may contribute to a reduced need for PPM. Postprocedural PPM implantation rates in our study (16.3%) were not as low as those reported by Forrest et al,¹² but were superior to those achieved using older-generation SEVs. Pagnesi et al¹¹ (12.8%) and Hellhammer et al¹³ (18.6%) demonstrated roughly similar results, while those reported by Rao et al²¹ (27.7%) were much higher. Unlike our results, none of the 3 studies found improved implantation rates over the compared device. Although conduction disturbances and PPM implantation have not yielded a consistent association with increased mortality, they have been associated with inferior outcomes known to affect prognosis.^25,26 Because PPM rates for SEVs are consistently inferior compared with balloon-expandable valves,^27-29 such an improvement in PPM rate might be particularly valuable for their future use.

In accord with all previous studies mentioned, we found excellent device success rates and lower complication rates using the EPV. Although the new EPV requires a minimal sheath diameter of 16 Fr (as opposed to the 14 Fr in the ERV), bleeding and complication rates were not significantly higher for EPV, which is in line with contemporary studies.³⁰

Study limitations. The study has several significant limitations. Its long timespan, during which operator experience accumulated and patient selection was optimized, skews results in favor of new devices. The retrospective nature of the study exposes it to inherent limitations and potentially to biased patient selection and treatment decisions that may have also influenced results. Propensity matching exposes the study to unmeasured biases, but was necessary due to large differences in the procedures performed. Following matching, significant baseline differences persisted, reflecting the shift toward treatment of healthier patients. Follow-up echocardiographic measurement timings were short and non-uniform, and our research did not include a core lab for echocardiographic assessment. Angiographic measurements were conducted by the operator performing the TAVR, exposing results to measurement bias, and were also influenced by the position of the pigtail catheter, amount and speed of contrast injection, and more; thus, measurements were not standardized. Conduction disturbances were also influenced by previous right bundle-branch block, height of implant, and other measurement data that were missing in our analysis.

The EPV is a bioprosthetic device; as such, its durability will need to be addressed in future studies, especially as TAVR is projected to be performed for lower-risk and younger patients. Nevertheless, TAVR bioprosthesis durability is gaining acceptance in contemporary studies.²⁴

Conclusion

Efficacy and safety outcomes using the third-generation EPV were excellent. Clinically meaningful postprocedural PVL rates were low, but were only improved as compared with the first-generation CV, as opposed to the second-generation ERV. Although not specifically designed to improve conduction disturbances, we report a significant reduction in need for PPM implantation using the EPV in comparison with both older-generation valves.

Affiliations and Disclosures

From the ¹Cardiology Department, Tel Aviv Medical Center, Israel, affiliated to Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel; ²Leviev Heart Center, Chaim Sheba Medical Center, Ramat Gan, Israel, affiliated to Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel; ³Cardiology Department, Hadassah Medical Center, Jerusalem, affiliated to the Hebrew University of Jerusalem, Jerusalem, Israel; ⁴Cardiology Department, Rabin Medical Center, Petach Tikva, Israel, affiliated to Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.

Disclosure: The authors have completed and returned the ICMJE Form for Disclosure of Potential Conflicts of Interest. Dr Finkelstein reports consulting fees from Medtronic and Edwards Lifesciences. Dr Halkin reports consulting fees from Abbott and Boston Scientific. The remaining authors report no conflicts of interest regarding the content herein.

Manuscript accepted June 26, 2021.

Address for correspondence: Arie Steinvil MD, Department of Cardiology, Tel Aviv Sourasky Medical Center, 6 Weizman Street, Tel Aviv 64239, Israel. Email: arikst@tlvmc.gov.il

References

1. Mack MJ, Leon MB, Thourani VH, et al. Transcatheter aortic-valve replacement with a balloon-expandable valve in low-risk patients. N Engl J Med. 2019;380(18):1695-1705. Epub 2019 Mar 16. doi: 10.1056/NEJMoa1814052

2. Popma JJ, Deeb GM, Yakubov SJ, et al. Transcatheter aortic-valve replacement with a self-expanding valve in low-risk patients. N Engl J Med. 2019;380(18):1706-1715. Epub 2019 Mar 16. doi: 10.1056/NEJMoa1816885

3. Popma JJ, Adams DH, Reardon MJ, et al. Transcatheter aortic valve replacement using a self-expanding bioprosthesis in patients with severe aortic stenosis at extreme risk for surgery. J Am Coll Cardiol. 2014;63(19):1972-1981. Epub 2014 Mar 19. doi: 10.1016/j.jacc.2014.02.556

4. Adams DH, Popma JJ, Reardon MJ, et al. Transcatheter aortic-valve replacement with a self-expanding prosthesis. N Engl J Med. 2014;371(10):967-968. doi: 10.1056/NEJMc1408396

5. Webb JG, Binder RK. Transcatheter aortic valve implantation: the evolution of prostheses, delivery systems and approaches. Arch Cardiovasc Dis. 2012;105(3):153-159. Epub 2012 Mar 16. doi: 10.1016/j.acvd.2012.02.001

6. Lenders GD, Collas V, Hernandez JM, et al. Depth of valve implantation, conduction disturbances and pacemaker implantation with CoreValve and CoreValve Accutrak system for transcatheter aortic valve implantation, a multi-center study. Int J Cardiol. 2014;176(3):771-775. Epub 2014 Aug 1. doi: 10.1016/j.ijcard.2014.07.092

7. Shah A, Stawiarski K, Gaddam S, Axiyan M, Fishman R, Tuohy E. Clinical outcomes for Medtronic Evolut-R versus CoreValve transcatheter aortic valve implantation. J Am Coll Cardiol. 2019;71(11 Suppl):A1134.

8. Popma JJ, Reardon MJ, Khabbaz K, et al. Early clinical outcomes after transcatheter aortic valve replacement using a novel self-expanding bioprosthesis in patients with severe aortic stenosis who are suboptimal for surgery: results of the Evolut R U.S. study. JACC Cardiovasc Interv. 2017;10(3):268-275. doi: 10.1016/j.jcin.2016.08.050

9. Thourani VH, Kodali S, Makkar RR, et al. Transcatheter aortic valve replacement versus surgical valve replacement in intermediate-risk patients: a propensity score analysis. Lancet. 2016;387(10034):2218-2225. Epub 2016 Apr 3. doi: 10.1016/S0140-6736(16)30073-3

10. Thyregod HGH, Steinbrüchel DA, Ihlemann N, et al. Transcatheter versus surgical aortic valve replacement in patients with severe aortic valve stenosis: 1-year results from the all-comers notion randomized clinical trial. J Am Coll Cardiol. 2015;65(20):2184-2194. Epub 2015 Mar 15. doi: 10.1016/j.jacc.2015.03.014

11. Hellhammer K, Piayda K, Afzal S, et al. The latest evolution of the Medtronic CoreValve system in the era of transcatheter aortic valve replacement: matched comparison of the Evolut PRO and Evolut R. JACC Cardiovasc Interv. 2018;11(22):2314-2322. doi: 10.1016/j.jcin.2018.07.023

12. Forrest JK, Mangi AA, Popma JJ, et al. Early outcomes with the Evolut PRO repositionable self-expanding transcatheter aortic valve with pericardial wrap. JACC Cardiovasc Interv. 2018;22;11(2):160-168. doi: 10.1016/j.jcin.2017.10.014

13. Pagnesi M, Kim W-K, Conradi L, et al. Transcatheter aortic valve replacement with next-generation self-expanding devices: a multicenter, retrospective, propensity-matched comparison of Evolut PRO versus Acurate neo transcatheter heart valves. JACC Cardiovasc Interv. 2019;12(5):433-443. doi: 10.1016/j.jcin.2018.11.036

14. Choudhury T, Solomonica A, Bagur R. The Evolut R and Evolut PRO transcatheter aortic valve systems. Expert Rev Med Devices. 2019;16(1):3-9. Epub 2018 Dec 16. doi: 10.1080/17434440.2019.1557045

15. Baumgartner H, Hung J, Bermejo J, et al. Recommendations on the echocardiographic assessment of aortic valve stenosis: a focused update from the European Association of Cardiovascular Imaging and the American Society of Echocardiography. Eur Heart J Cardiovasc Imaging. 2017;18(3):254-275. doi: 10.1093/ehjci/jew335

16. Medtronic. CoreValve system. Transcatheter aortic valve delivery catheter system compression loading system. Accessed March 23, 2022. https://www.medtronic.com/us-en/healthcare-professionals/products/cardiovascular/transcatheter-aortic-heart-valves/indications-safety-and-warnings.html

17. Medtronic. CoreValve Evolut R system. CoreValve Evolut R transcatheter aortic valve delivery catheter system loading system. Accessed March 23, 2022. https://www.medtronic.com/us-en/healthcare-professionals/products/cardiovascular/transcatheter-aortic-heart-valves/evolut-r.html

18. Medtronic. CoreValve Evolut PRO system. CoreValve Evolut PRO transcatheter aortic valve delivery catheter system loading system. Accessed March 23, 2022. https://www.medtronic.com/us-en/healthcare-professionals/products/cardiovascular/transcatheter-aortic-heart-valves/evolut-pro-plus.html

19. Kappetein AP, Head SJ, Généreux P, et al; for the Valve Academic Research Consortium (VARC)-2. Updated standardized endpoint definitions for transcatheter aortic valve implantation: the Valve Academic Research Consortium-2 consensus document. Eur J Cardiothorac Surg. 2012;42(5):S45-S60. Epub 2012 Oct 1. doi: 10.1093/ejcts/ezs533

20. Athappan G, Patvardhan E, Tuzcu EM, et al. Incidence, predictors, and outcomes of aortic regurgitation after transcatheter aortic valve replacement: meta-analysis and systematic review of literature. J Am Coll Cardiol. 2013;61(15):1585-1595. doi: 10.1016/j.jacc.2013.01.047

21. Rao G, Sheth S, Donnelly J, et al. Early real-world experience with CoreValve Evolut Pro and R systems for transcatheter aortic valve replacement. J Interv Cardiol. 2019:1906814. doi: 10.1155/2019/1906814

22. Eleid MF, Cabalka AK, Malouf JF, Sanon S, Hagler DJ, Rihal CS. Techniques and outcomes for the treatment of paravalvular leak. Circ Cardiovasc Interv. 2015;8(8):e001945. doi: 10.1161/CIRCINTERVENTIONS.115.001945

23. Williams M, Qiao H, Forrest J. 1-year outcomes with the Evolut Pro self-expanding repositionable transcatheter aortic valve with pericardial wrap. Presented at the: American College of Cardiologists (ACC) meeting. March 10, 2018, Orlando, Florida.

24. Blackman DJ, Saraf S, MacCarthy PA, et al. Long-term durability of transcatheter aortic valve prostheses. J Am Coll Cardiol. 2019;73(5):537-545. doi: 10.1016/j.jacc.2018.10.078

25. Regueiro A, Abdul-Jawad Altisent O, Del Trigo M, et al. Impact of new-onset left bundle branch block and periprocedural permanent pacemaker implantation on clinical outcomes in patients undergoing transcatheter aortic valve replacement: a systematic review and meta-analysis. Circ Cardiovasc Interv. 2016;9(5):e003635. doi: 10.1161/CIRCINTERVENTIONS.115.003635

26. Fadahunsi OO, Olowoyeye A, Ukaigwe A, et al. Incidence, predictors, and outcomes of permanent pacemaker implantation following transcatheter aortic valve replacement: analysis from the U.S. Society of Thoracic Surgeons/American College of Cardiology TVT Registry. JACC Cardiovasc Interv. 2016;9(21):2189-2199. doi: 10.1016/j.jcin.2016.07.026

27. Siontis GCM, Jüni P, Pilgrim T, et al. Predictors of permanent pacemaker implantation in patients with severe aortic stenosis undergoing TAVR: a meta-analysis. J Am Coll Cardiol. 2014;64(2):129-140. doi: 10.1016/j.jacc.2014.04.033

28. Vlastra W, Chandrasekhar J, Muñoz-Garcia AJ, et al. Comparison of balloon-expandable vs. self-expandable valves in patients undergoing transfemoral transcatheter aortic valve implantation: from the CENTER-collaboration. Eur Heart J. 2019;40(5):456-465. doi: 10.1093/eurheartj/ehy805

29. Van Belle E, Vincent F, Labreuche J, et al. Balloon-expandable versus self-expanding transcatheter aortic valve replacement. Circulation. 2020;141(4):243-259. Epub 2019 Nov 16. doi: 10.1161/CIRCULATIONAHA.119.043785

30. Tummala R, Banerjee K, Sankaramangalam K, et al. Clinical and procedural outcomes with the SAPIEN 3 versus the SAPIEN XT prosthetic valves in transcatheter aortic valve replacement: a systematic review and meta-analysis. Catheter Cardiovasc Interv. 2018;92(3):E149-E158. Epub 2017 Oct 25. doi: 10.1002/ccd.27398