Reasons for Screen Failure for Transcatheter Mitral Valve Repair and Replacement

Screen failures in clinical trials in retina

PURPOSE

Disparities in clinical trials are a major problem due to significant underrepresentation of certain gender, racial and ethnic groups. Several factors including stringent eligibility criteria and recruitment strategies hinder our understanding of retinal disease. Thus, we aimed to study the various reasons of screen failures and specific patient and study characteristics among screen failures.

DESIGN

This is a cross-sectional retrospective study METHODS: Screening data of 87 trials from 6 centers were analyzed. Study characteristics (disease studied, phase of trial, route of drug administration) and patient demographics (age, gender, race, ethnicity, and employment status) were compared among different causes of screen failures. Screen failures were broadly classified into six categories: exclusion due to vision-based criteria, exclusion due to imaging findings, exclusion due to other factors, patient-related criteria, physician related criteria and miscellaneous. Descriptive statistics, Pearson Chi-square test and ANOVA were used for statistical analysis.

MAIN OUTCOME MEASURES

Determine the prevalence of various reasons for screen failures in multiple trials and its trend among different study and patient characteristics.

RESULTS

Among 87 trials and 962 patients, 465(48.2%) patients were successfully randomized and 497(51.8%) patients were classified as screen failures. The trials were conducted for various retinal diseases. Mean age was 76.50 ±10.45 years and 59.4% were females. Predominantly whites(93.4%) and unemployed/retired patients(66.6%) were screened. Of the 497 screen failures, most were due to patients not meeting inclusion criteria of imaging findings (n=221[44.5%]) followed by inclusion of vision-based criteria (n=73 [14.7%]), exclusion due to other factors (n=75[15.1%]), patient-related (n=34[6.8%]), physician-related (n=28[5.6%]) and miscellaneous reasons (n= 39[17.8%]). Reason for screen failure was not available for 27(5.4%) patients. A higher proportion of patients screened for surgical trials (15%) declined to participate in the study compared to non-invasive trials involving topical drugs and photobiomodulation (0%).(p=0.02) CONCLUSION: Patients not meeting the imaging and vision-cased criteria were the most common reasons for screen failures. Whites and unemployed patients predominantly participated in clinical trials. Patients are more inclined to continue participation in non-invasive clinical trials compared to surgical trials. Better recruitment strategies and careful consideration of study criteria can aid in decreasing the rate of screen failures.

Etiologies and Impact of Exclusion Rates for Transcatheter Mitral and Tricuspid Valve Structural Heart Clinical Trials at a High-Volume Quaternary Care Hospital

There are various devices under clinical investigation for transcatheter mitral valve intervention and transcatheter tricuspid valve intervention (TTVI); however, the exclusion rates remain high. We aimed to investigate the exclusion rates for transcatheter mitral valve repair (TMVr), transcatheter mitral valve replacement (TMVR), transcatheter tricuspid valve repair (TTVr), and transcatheter tricuspid valve replacement (TTVR). There were 129 patients who were referred to St. Francis Hospital & Heart Center valve clinic and completed screening between January 2021 and July 2022. The causes for exclusion were classified into 4 categories: patient withdrawal, anatomic unsuitability, clinical criteria, and medical futility. In 129 patients, the exclusion rates for TMVr, TMVR, TTVr, and TTVR were 81%, 85%, 91%, and 87%, respectively. Patient withdrawal and medical futility were leading etiologies for exclusion, followed by anatomic unsuitability. TMVr had the highest rate of patient withdrawal (64%) and the lowest anatomic unsuitability (5%) because of short posterior leaflet length. Replacement interventions have a higher anatomic unsuitability (33%) than repair interventions (17%) (p = 0.04). Most exclusions of anatomic unsuitability were because of mitral stenosis or small annulus size for TMVR and large annulus size for TTVR. A total of 50% of exclusions from TTVr were because of the presence of pacemaker/defibrillator leads. In patients excluded from their respective trials, patients being referred for TMVr had the highest recurrent hospitalization and repair group had a higher mortality (p <0.01 and p = 0.01, respectively). In conclusion, the exclusion rates for transcatheter mitral valve intervention and TTVI trials remain high because of various reasons, limiting patient enrollment and treatment. This supports the need for further device improvement or exploring alternative means of therapy.

Transcatheter transseptal treatment of patients with severe mitral regurgitation using an atrial fixation mitral valve replacement technology

BACKGROUND

Mitral regurgitation (MR) is the most common valvular heart disease worldwide with a 5-year mortality rate of 50 % with medical therapy alone. Several transcatheter mitral valve replacement (TMVR) devices are being investigated in clinical trials. Early evidence has demonstrated clinical benefits with a reduction in heart failure symptoms, low rates of residual MR, and reverse remodeling of the left ventricle (LV) over time. However, high anatomical screen failure rates limit its applicability. The primary reasons for the anatomical screen failure are risk of LV outflow tract obstruction, large mitral valve annulus size, and the presence of mitral annular calcification. Our clinical experiences using an atrial only fixation TMVR technology delivered via a transfemoral-transseptal approach is described.

METHODS

Three consecutive patients with severe functional MR underwent TMVR implantation using an atrial only fixation technology and a low-profile transseptal delivery system.

RESULTS

Technical success was achieved in 100 % of the patients with a clinically significant reduction in MR. Longer-term follow-up (up to 6-months) has demonstrated a sustained reduction in MR and significant improvement in quality of life for all patients.

CONCLUSIONS

Longer-term outcomes in our patients showed persistent reduction in MR, sustained implant performance, and notable improvements in NYHA Class and quality of life. There were no major adverse events. Follow-up CT data showed no evidence of device-related thrombosis, with stable valve position and integrity. The atrial fixation TMVR technology may have benefits in preserving the dynamics of the native mitral valve annulus thereby reducing the overall risk of LVOT obstruction.

SHORT ABSTRACT

We present a single-center experience of three consecutive patients with severe functional MR treated with the AltaValve using a low-profile transseptal delivery system. A clinically significant reduction in mitral regurgitation was achieved in all patients, and longer-term follow-up has demonstrated sustained clinical benefits.

Mitral Interventions in Heart Failure

Patients with heart failure with reduced ejection fraction who have secondary mitral regurgitation (SMR) have poorer outcomes and quality of life than those without SMR. Guideline-directed medical therapy is the cornerstone of SMR treatment. Careful evaluation of landmark trials using mitral transcatheter edge-to-edge repair in SMR has led to an improved understanding of who will benefit from percutaneous interventions with emphasis on a multidisciplinary approach. The success with mitral transcatheter edge-to-edge repair in SMR has also spurred the evaluation of its role in populations that were not initially studied, such as end-stage heart failure and cardiogenic shock. A spectrum of transcatheter devices in development and clinical trials promise to further provide a growing array of management options for heart failure with reduced ejection fraction patients with symptomatic SMR.

Contemporary Treatment and Outcomes of High Surgical Risk Mitral Regurgitation

Before the development of transcatheter interventions, patients with mitral regurgitation (MR) and high surgical risk were often conservatively treated and subject to poor prognoses. We aimed to assess the therapeutic approaches and outcomes in the contemporary era. The study participants were consecutive high-risk MR patients from April 2019 to October 2021. Among the 305 patients analyzed, 274 (89.8%) underwent mitral valve interventions, whereas 31 (10.2%) received medical therapy alone. Of the interventions, transcatheter edge-to-edge mitral repair (TEER) was the most frequent (82.0% of overall), followed by transcatheter mitral valve replacement (TMVR) (4.6%). In patients treated with medical therapy alone, non-optimal morphologies for TEER and TMVR were shown in 87.1% and 65.0%, respectively. Patients undergoing mitral valve interventions experienced less frequent heart failure (HF) rehospitalization compared to those with medical therapy alone (18.2% vs. 42.0%, p < 0.01). Mitral valve intervention was associated with a lower risk of HF rehospitalization (HR 0.36 [0.18-0.74]) and an improved New York Heart Association class (p < 0.01). Most high-risk MR patients can be treated with mitral valve interventions. However, approximately 10% remained on medical therapy alone and were considered as unsuitable for current transcatheter technologies. Mitral valve intervention was associated with a lower risk of HF rehospitalization and improved functional status.

The Clinical Profile and Natural History of Patients Who Fail Screening for Transcatheter Mitral Valve Replacement: Rationale and Design of the Prospective Multicenter Mitral Valve Screening Survey (MVSS)

Mitral valve disease is insidious and associated with a decreased quality of life and survival over time. Despite surgery being the standard of care, many patients are at prohibitive surgical risk. Furthermore, a substantial proportion of patients with symptomatic mitral valve disease fail stringent screening criteria for transcatheter mitral valve replacement (TMVR). The natural history of patients who fail screening is not well-characterized, and data are limited on the reasons for screen failure in this population. The Mitral Valve Screening Survey (MVSS) seeks to detail the clinical profile and natural history of patients who fail screening for TMVR. The MVSS is a prospective, multicenter registry enrolling up to 1000 consecutive subjects who, after screening for TMVR, are deemed not to be candidates. Subjects will be followed for 30 days after failing screening for TMVR and annually for up to 5 years with clinical evaluations. The primary study endpoint of the MVSS registry is all-cause mortality at 1 year. Additional secondary endpoints include all-cause mortality, hospitalizations, subsequent mitral valve intervention (transcatheter or surgical), reason for screen failure, and quality-of-life assessments at 30 days and annually up to 5 years of follow-up. The MVSS registry is the first prospective multicenter study to characterize the clinical and anatomical profile of patients who fail screening for TMVR while providing longitudinal clarification on the natural history and outcomes of these patients. CLINICAL TRIAL REGISTRATION: Mitral Valve Screening Survey (MVSS), https://clinicaltrials.gov/ct2/show/NCT04736667, NCT04736667.

Audit of screen failure in 15 randomised studies from a low and middle-income country

Background

Growth and development in patient management occurs via randomised studies. Screen failure is a significant hurdle while conducting randomised studies. There is limited data available from low and middle-income countries about factors resulting in screen failure. Hence, this audit was performed to identify the proportion of patients who screen failed and to elucidate reasons for the same.

Methods

This was an audit of 15 randomised studies performed by medical oncology solid tumour unit II of Tata Memorial Centre. The screening logs of these studies were acquired. From the screening logs, data regarding the number of patients who had screen failed & reason for the same were obtained. Descriptive statistics were performed.

Results

A total of 7,481 patients were screened for 15 randomised clinical studies. Out of these, 3,666 (49.0%) patients were enrolled into trials and 3,815 (51.0%) screen failed. The most common reason for screen failure was 'not meeting inclusion criteria' (54.9%) followed by declining to take treatment (22.2%). Other factors that affect enrolment were 'not willing to stay in the locality of the trial site' (6.2%), being recruited in other studies (3.7%), poor performance status (PS) (3.4%), non-compliance (2.2%), meeting exclusion criteria (0.9%) and 'other' (6.5%).

Conclusion

The commonest causes of screen failure in lower and middle-income countries are non-meeting of inclusion criteria followed by declining to take treatment, not willing to stay in locality of trial site, recruited into other studies, poor PS, non-compliance, meeting exclusion criteria & 'other'. This information would help analysing and hence planning of newer strategies to decrease the rate of screen failure.

Use of Electrosurgery in Interventional Cardiology

Transcatheter electrosurgery is a versatile tool that can be used to cut cardiac tissue without the need for a sternotomy, cardiopulmonary bypass, and cardioplegia. With adequate imaging and suitable anatomy, any cardiac tissue can be cut. Thus, transcatheter electrosurgery can provide bespoke therapies for complex patients who often have no other good treatment options. In this review, we will discuss the common applications for electrosurgical tissue traversal and laceration, including transcaval access, BASILICA, LAMPOON, and ELASTA-Clip, summarizing the evidence and the key technical steps for each.