Prosthesis-patient mismatch after transcatheter aortic valve implantation with the Medtronic-Corevalve bioprosthesis

Aims: Prosthesis-patient mismatch (P-PM) is an important determinant of morbidity and mortality following open aortic valve replacement. The aims of this study were to report its incidence and determinants following transcatheter aortic valve implantation (TAVI) with the Corevalve bioprosthesis, which have—thus far—not been described. Methods and results: Patients with severe calcific aortic stenosis received TAVI with the Corevalve bioprosthesis via transfemoral route. Following TAVI, moderate P-PM was defined as indexed aortic valve effective orifice area (AVAi) ≤0.85 cm2/m2 and severe P-PM as AVAi ≤0.65 cm2/m2. Clinical, echocardiographic, and procedural factors relating to P-PM were studied. Optimal device position was defined on fluoroscopy as final position of the proximal aspect of the Corevalve stent frame 5–10 mm below the native aortic annulus. Between January 2007 and January 2009, 50 consecutive patients underwent TAVI in a single centre with the Corevalve bioprosthesis. Mean age was 82.8 years (SD 5.9; 70–93) and 48% were male. P-PM occurred in 16 of 50 cases (32%). Optimal position was achieved in 50% of cases. P-PM was unrelated to age, annulus size, LVOT size, Corevalve size, aortic angulation, ejection fraction, and sex. It was inversely correlated to optimal position (Spearman rho r = −0.34, P = 0.015). Those with optimal positioning had a 16% incidence of P-PM relative to 48% of those with suboptimal positioning (Pearson χ2P = 0.015). Conclusion: The incidence of P-PM following TAVI with the Corevalve bioprosthesis is compared favourably with that seen after AVR with conventional open stented bioprostheses and its occurrence is influenced by device positioning

Leaflet thrombosis in transcatheter aortic valve intervention: mechanisms, prevention, and treatment options

IntroductionTranscatheter aortic valve intervention (TAVR) has emerged as a promising alternative to surgical aortic valve replacement for patients with severe aortic stenosis. However, leaflet thrombosis has raised concerns about the long-term durability and outcomes of TAVR. This study aims to provide an overview of the mechanisms, prevention strategies, and treatment options for leaflet thrombosis in TAVR.Clinical evidenceLeaflet thrombosis refers to the formation of blood clots on bioprosthetic valve leaflets, leading to impaired leaflet mobility, early valve degeneration and dysfunction, and potential clinical implications. While the mechanisms underlying thrombus formation on valve leaflets are not fully understood, several factors, such as altered blood flow patterns within valve neosinuses, prothrombotic surfaces, and patient-related causes, have been implicated. Two distinct entities have been identified, namely, hypoattenuated leaflet thickening and restricted leaflet motion. Their occurrence appears dynamic over time and is related to the valve type. Imaging, including transesophageal echocardiography and multidetector computed tomography, plays a crucial role in the diagnosis and follow-up of leaflet thrombosis.Prevention and treatment optionsPreventing leaflet thrombosis requires a comprehensive and tailored approach involving identifying high-risk patients, close monitoring, and antithrombotic therapy. Antithrombotic therapy with dual antiplatelet agents or anticoagulation is commonly employed in TAVR patients, although the optimal regimen is yet to be defined. Novel antithrombotic agents, such as direct oral anticoagulants, are being investigated for their efficacy and safety in preventing leaflet thrombosis. When leaflet thrombosis is detected, treatment options include intensified antithrombotic therapy, valve-in-valve intervention, or balloon valvuloplasty. The long-term outcomes and impact of leaflet thrombosis on valve durability and patient prognosis are areas of ongoing research.SummaryLeaflet thrombosis in TAVR is a considerable complication affecting valve function and patient outcomes. Understanding the mechanisms underlying thrombus formation and implementing appropriate prevention strategies are essential for mitigating this risk. Treatment options aim to restore leaflet mobility and optimize valve performance. Further research is needed to establish standardized protocols for antithrombotic therapy, identify high-risk patient populations, and determine the long-term consequences of leaflet thrombosis on TAVR outcomes

Predicting the risk of iliofemoral vascular complication in complex transfemoral-TAVR using new generation transcatheter devices.

OBJECTIVE: Design a predictive risk model for minimizing iliofemoral vascular complications (IVC) in a contemporary era of transfemoral-transcatheter aortic valve replacement (TF-TAVR). BACKGROUND: IVC remains a common complication of TF-TAVR despite the technological improvement in the new-generation transcatheter systems (NGTS) and enclosed poor outcomes and quality of life. Currently, there is no accepted tool to assess the IVC risk for calcified and tortuous vessels. METHODS: We reconstructed CT images of 516 propensity-matched TF-TAVR patients using the NGTS to design a predictive anatomical model for IVC and validated it on a new cohort of 609 patients. Age, sex, peripheral artery disease, valve size, and type were used to balance the matched cohort. RESULTS: IVC occurred in 214 (7.2%) patients. Sheath size (p = 0.02), the sum of angles (SOA) (p < .0001), number of curves (NOC) (p < .0001), minimal lumen diameter (MLD) (p < .001), and sheath-to-femoral artery diameter ratio (SFAR) (p = 0.012) were significant predictors for IVC. An indexed risk score (CSI) consisting of multiplying the SOA and NOC divided by the MLD showed 84.3% sensitivity and 96.8% specificity, when set to >100, in predicting IVC (C-stat 0.936, 95% CI 0.911-0.959, p < 0.001). Adding SFAR > 1.00 in a tree model increased the overall accuracy to 97.7%. In the validation cohort, the model predicted 89.5% of the IVC cases with an overall 89.5% sensitivity, 98.9% specificity, and 94.2% accuracy (C-stat 0.842, 95% CI 0.904-0.980, p < .0001). CONCLUSION: Our CT-based validated-model is the most accurate and easy-to-use tool assessing IVC risk and should be used for calcified and tortuous vessels in preprocedural planning

Stratification of Outcomes After Transcatheter Aortic Valve Replacement According to Surgical Inoperability for Technical Versus Clinical Reasons

ObjectivesThe goal of this study was to examine the impact of reasons for surgical inoperability on outcomes in patients undergoing transcatheter aortic valve replacement (TAVR).BackgroundPatients with severe aortic stenosis may be deemed inoperable due to technical or clinical reasons. The relative impact of each designation on early and late outcomes after TAVR is unclear.MethodsPatients were studied from the inoperable arm (cohort B) of the randomized PARTNER (Placement of Aortic Transcatheter Valve) trial and the nonrandomized continued access registry. Patients were classified according to whether they were classified as technically inoperable (TI) or clinically inoperable (CLI). Reasons for TI included porcelain aorta, previous mediastinal radiation, chest wall deformity, and potential for injury to previous bypass graft on sternal re-entry. Reasons for CLI were systemic factors that were deemed to make survival unlikely.ResultsOf the 369 patients, 23.0% were considered inoperable for technical reasons alone; the remaining were judged to be CLI. For TI, the most common cause was a porcelain aorta (42%); for CLI, it was multiple comorbidities (48%) and frailty (31%). Quality of life and 2-year mortality were significantly better among TI patients compared with CLI patients (mortality 23.3% vs. 43.8%; p < 0.001). Nonetheless, TAVR led to substantial survival benefits compared with standard therapy in both inoperable cohorts.ConclusionsPatients undergoing TAVR based solely on TI have better survival and quality of life improvements than those who are inoperable due to clinical comorbidities. Both TI and CLI TAVR have significant survival benefit in the context of standard therapy. (THE PARTNER TRIAL: Placement of AoRTic TraNscathetER Valve Trial; NCT00530894

Feasibility study of temporary permanent pacemaker in patients with conduction block after TAVR

BackgroundLimited data exist on the use of temporary permanent pacemaker (TPPM) to reduce unnecessary PPM in patients with high-degree atrioventricular block (HAVB) after transcatheter aortic valve replacement (TAVR).ObjectivesThis study aims to determine the feasibility of TPPM in patients with HAVB after TAVR to provide prolonged pacing as a bridge.Materials and methodsOne hundred and eleven consecutive patients undergoing TAVR were screened from August 2021 to June 2022. Patients with HAVB eligible for PPM were included. TPPM were used in these patients instead of conventional temporary pacing or early PPM. Patients were followed up for 1 month. Holter and pacemaker interrogation were used to determine whether to implant PPM.ResultsTwenty one patients met the inclusion criteria for TPPM, of which 14 patients were third-degree AVB, 1 patient was second-degree AVB, 6 patients were first degree AVB with PR interval &gt; 240 ms and LBBB with QRS duration &gt; 150 ms. TPPM were placed on the 21 patients for 35 ± 7 days. Among 15 patients with HAVB, 26.7% of them (n = 4) recovered to sinus rhythm; 46.7% (n = 7) recovered to sinus rhythm with bundle branch block. The remains of 26.7% patients (n = 4) still had third-degree AVB and received PPM. For patients with first-degree AVB and LBBB, PR interval shortened to &lt; 200 ms in all 6 patients and LBBB recovered in 2 patients. TPPM were successfully removed from all patients and no procedure-related adverse events occurred.ConclusionTPPM is reliable and safe in the small sample of patients with conduction block after TAVR to provide certain buffer time to distinguish whether a PPM is necessary. Future studies with larger sample are needed for further validation of the current results