Dataset Information

Assessing the Hemodynamic Impact of Anterior Leaflet Laceration in Transcatheter Mitral Valve Replacement: An in silico Study.

ABSTRACT:

Background

A clinical study comparing the hemodynamic outcomes of transcatheter mitral valve replacement (TMVR) with vs. without Laceration of the Anterior Mitral leaflet to Prevent Outflow Obstruction (LAMPOON) has never been designed nor conducted.

Aims

To quantify the hemodynamic impact of LAMPOON in TMVR using patient-specific computational (in silico) models.

Materials

Eight subjects from the LAMPOON investigational device exemption trial were included who had acceptable computed tomography (CT) data for analysis. All subjects were anticipated to be at prohibitive risk of left ventricular outflow tract (LVOT) obstruction from TMVR, and underwent successful LAMPOON immediately followed by TMVR. Using post-procedure CT scans, two 3D anatomical models were created for each subject: (1) TMVR with LAMPOON (performed procedure), and (2) TMVR without LAMPOON (virtual control). A validated computational fluid dynamics (CFD) paradigm was then used to simulate the hemodynamic outcomes for each condition.

Results

LAMPOON exposed on average 2 ± 0.6 transcatheter valve cells (70 ± 20 mm² total increase in outflow area) which provided an additional pathway for flow into the LVOT. As compared to TMVR without LAMPOON, TMVR with LAMPOON resulted in lower peak LVOT velocity, lower peak LVOT gradient, and higher peak LVOT effective orifice area by 0.4 ± 0.3 m/s (14 ± 7% improvement, p = 0.006), 7.6 ± 10.9 mmHg (31 ± 17% improvement, p = 0.01), and 0.2 ± 0.1 cm² (17 ± 9% improvement, p = 0.002), respectively.

Conclusion

This was the first study to permit a quantitative, patient-specific comparison of LVOT hemodynamics following TMVR with and without LAMPOON. The LAMPOON procedure achieved a critical increment in outflow area which was effective for improving LVOT hemodynamics, particularly for subjects with a small neo-left ventricular outflow tract (neo-LVOT).

SUBMITTER: Kohli K

PROVIDER: S-EPMC9261975 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:BackgroundLeft ventricular outflow tract (LVOT) obstruction is a leading cause of mortality and exclusion from transcatheter mitral valve replacement (TMVR). Intentional laceration of the anterior mitral valve leaflet to prevent LVOT obstruction (LAMPOON) is a transcatheter mimic of surgical chord-sparing leaflet resection.ObjectivesThe purpose of this prospective multicenter trial was to study LAMPOON with transseptal (Edwards Lifesciences, Irvine, California) TMVR in annuloplasty rings or native mitral annular calcification (MAC).MethodsSubjects at high or extreme surgical risk and prohibitive risk of LVOT obstruction from TMVR were included. Eligibility was modified midtrial to exclude subjects with threatened LVOT obstruction from a Sapien 3 valve fabric skirt. The primary endpoint was procedure survival with successful LAMPOON, with successful TMVR, without reintervention, and with LVOT gradient <30 mm Hg ("optimal") or <50 mm Hg ("acceptable"). Secondary endpoints included 30-day mortality and major adverse cardiovascular events. There was universal source-data verification and independent monitoring. All endpoints were independently adjudicated. Central laboratories analyzed echocardiogram and CT images.ResultsBetween June 2017 and June 2018, 30 subjects were enrolled equally between the MAC and ring arms. LAMPOON traversal and midline laceration was successful in 100%. Procedure survival was 100%, and 30-day survival was 93%. Primary success was achieved in 73%, driven by additional procedures for paravalvular leak (10%) and high-skirt neo-LVOT gradients observed before a protocol amendment. There were no strokes.ConclusionsLAMPOON was feasible in native and annuloplasty ring anatomies in patients who were otherwise ineligible for treatment, with acceptable safety. LAMPOON was effective in preventing LVOT obstruction from TMVR. Despite LAMPOON, TMVR using Sapien 3 in annuloplasty rings and MAC still exhibits important limitations. (NHLBI DIR LAMPOON Study: Intentional Laceration of the Anterior Mitral Leaflet to Prevent Left Ventricular Outflow Tract Obstruction During Transcatheter Mitral Valve Implantation; NCT03015194).

Project description:ObjectivesThe aim of this study was to test the hypothesis that transcatheter electrosurgery might allow intentional detachment of previously placed MitraClip(s) from the anterior leaflet to recreate a single mitral orifice for transcatheter mitral valve implantation (TMVI), leaving the retained MitraClip(s) securely fastened to the posterior leaflet and without interfering with the mitral bioprosthesis.BackgroundPatients with severe mitral regurgitation or stenosis despite edge-to-edge mitral repair with the MitraClip typically have few therapeutic options because the resultant double orifice precludes TMVI. Transcatheter electrosurgery may allow detachment of failed MitraClip(s) from the anterior leaflet to recreate a single orifice for TMVI.MethodsThis was a single-center, 5-patient, consecutive, retrospective observational cohort. Patients underwent transcatheter electrosurgical laceration and stabilization of failed MitraClip(s) to recreate a single orifice, leaving the MitraClip(s) securely fastened to the posterior leaflet. Subsequently, patients underwent TMVI with an investigational device, the Tendyne mitral bioprosthesis, on a compassionate basis. Patients were followed up to 30 days.ResultsMitraClip detachment from the anterior leaflet and Tendyne implantation were successful in all patients. All patients survived to discharge. All patients were discharged with grade 0 central mitral regurgitation. Two patients had moderate perivalvular mitral regurgitation that did not require reintervention. During the follow-up period of 30 days, there were no deaths, cases of valve dysfunction, or reintervention. There was no evidence of erosion or bioprosthetic valve dysfunction attributable to the retained MitraClip(s) still attached to the posterior leaflet.ConclusionsTranscatheter electrosurgical detachment of failed MitraClips from the anterior leaflet followed by TMVI is technically feasible and safe at 30 days. Longer term study is needed to determine the clinical benefit of this approach and new algorithms for TMVI sizing following electrosurgical laceration and stabilization of a failed MitraClip to avoid perivalvular leak.