Duplication of the tricuspid valve

Duplication of the atrioventricular (AV) valves is a rare anomaly, more commonly seen in the mitral position. Only 13 cases have been reported in the literature.(1-10) The case described here represents an unusual variant of this anomaly and provides an opportunity to review the pathology and embryologic genesis of duplication deformities of the AV valves.     

Robotic artificial chordal replacement for repair of mitral valve prolapse

Artificial chordal replacement (ACR) has emerged as a superior method of mitral valve repair with excellent early and late efficacy. It is also ideal to combine with robotic techniques for correction of mitral prolapse, and this article presents a current method of robotic Gore-Tex ACR. Patients with isolated posterior leaflet prolapse are approached with the fourth-generation DaVinci robotic system and endoaortic balloon occlusion. A pledgetted anchor stitch is placed in a papillary muscle, and a 2-o Gore-Tex suture is passed through the anchor pledget. After full annuloplasty ring placement, the Gore-Tex suture is woven into the prolapsing segment and positioned temporarily with robotic forceps. Chordal length is then "adjusted" by lengthening or shortening the temporary knot over 1-cm increments as the valve is tested by injection of cold saline into the ventricle. After achieving good leaflet position and valve competence, the chord is tied permanently. The "adjustable" ACR procedure preserves leaflet surface area and produces a competent valve in the majority of patients. Postoperative transesophageal echo shows a large surface area of coaptation. Patient recovery is facilitated by the minimally invasive approach, while long-term stability of similar open ACR techniques have been excellent with a 2% to 3% failure rate over 10 years of follow-up. Robotic Gore-Tex ACR without leaflet resection is a reproducible procedure that simplifies mitral repair for prolapse. The outcomes observed in early robotic applications have been excellent. It is suggested that most patients with simple prolapse might validly be approached in this manner.     

Transcatheter tricuspid valve repair: early experience in the Netherlands

BackgroundSymptomatic tricuspid regurgitation (TR) is increasingly prevalent and impairs quality of life and survival, despite medical treatment. Transcatheter tricuspid valve repair (TTVR) has recently become available as a treatment option for patients not eligible for tricuspid valve surgery. In this study we describe the early experience with TTVR in the Netherlands.MethodsAll consecutive patients scheduled for TTVR in two tertiary hospitals were included in the current study. Patients were symptomatic and had severe functional TR. TTVR was performed either with the MitraClip (off-label use) or dedicated TriClip delivery system and device. Procedural success was defined as achievement of clip implantation, TR reduction ≥ 1 grade and no need for re-do surgical or transcatheter intervention. Clinical improvement was evaluated after 4 weeks.ResultsTwenty-one patients (median age 78 years, 33% male, 95% New York Heart Association class ≥ 3, 100% history of atrial fibrillation) underwent TTVR. Procedural success was achieved in 16 patients, of whom 15 reported symptomatic improvement (New York Heart Association class 1 or 2). There was no in-hospital mortality and no major complications occurred. Baseline glomerular filtration rate and TR coaptation gap size were associated with procedural success.ConclusionThe current study showed that TTVR seems a promising treatment option for patients with severe functional TR deemed high risk for surgery. Successful TR reduction is most likely in patients with limited coaptation gap size and strongly determines clinical benefit. Adequate patient selection and timing of treatment seem essential for an optimal patient outcome.Supplementary InformationThe online version of this article (10.1007/s12471-021-01613-3) contains supplementary material, which is available to authorized users.     

Measurement of discrete vertical in-shoe stress with piezoelectric transducers

The purpose of this investigation was to design and validate a system suitable for non-invasive measurement of discrete in-shoe vertical plantar stress during dynamic activities. Eight transducers were constructed, with small piezoelectric ceramic squares (4.83 × 4.83 × 1.3 mm) used to generate a charge output proportional to vertical plantar stress. The mechanical properties of the transducers included 2.3% linearity and 3.7% hysteresis for stresses up to 2000 kPa and loading times up to 200 ms. System design efficacy was analysed by means of a multiple day, multiple trial data collection. With the transducers placed beneath plantar landmarks, the footstrike of one subject was recorded ten times on each of five days while running at 3.58 m/s on a treadmill. Within-day and between-day proportional error (PE) was used to estimate the error contained in the mean peak stress during foot contact. Within-day PE focused on trial to trial variability associated with the subject and equipment, and averaged 3.1% (range 2.5–4.0%) across transducer location. Between-day PE provided a cumulative estimate of subject, transducer placement, and random equipment variability, but excluded trial to trial variability. It ranged from 4.9 to 15.8%, with a mean of 9.9%. Peak stress, impulse, and sequence of loading data were examined to identify discrete foot function patterns and highlight the value of discrete stress analysis.     

Longitudinal echocardiographic and clinical follow-up of patients undergoing mitral valve surgery without concomitant tricuspid valve repair

Background

In patients with mild to moderate functional tricuspid regurgitation (TR) and absence of right ventricular dysfunction or tricuspid annulus (TA) dilatation, there is currently no indication for concomitant tricuspid valve (TV) repair during elective mitral valve (MV) surgery. However, long-term results are conflicting. Here, we sought to determine the clinical outcome of this cohort, the rate of TR progression after MV surgery and the role of MV aetiology.

Methods

Patients for elective MV surgery without concomitant TV repair were retrospectively analysed with longitudinal echocardiographic and clinical follow-up, focusing on TR progression and MV aetiology. Linear regression analysis was performed for change in TR at follow-up, using pre-determined variables and confounders.

Results

In total 204 patients without TV repair were analysed. Development of more than moderate TR after a median of 3.1 [1.6–4.6] years was rarely seen: only in 2 out of 161 patients (1.2%) with known TR grade at follow-up. Overall, median preoperative and late postoperative TR grade were equal (p?=?0.116). Subanalysis showed no significant difference in MV aetiology subgroups. Preoperative TR grade and male gender were inversely correlated to change in TR. Mortality was not influenced by the 1?year postoperative TR severity.

Conclusion

Our data showed that in a study population of patients with mild to moderate TR undergoing MV surgery without concomitant TV repair, significant late TR was rarely seen. Based on our study, it is safe to waive concomitant TV repair in this specific patient cohort.

     

Catalytic durability of magnetoproteoliposomes captured by high-gradient magnetic forces in a miniature fixed-bed reactor

Cytochrome c-oxidase, used as a model membrane-bound enzyme, was embedded in phospholipid bilayer membranes, attached to nanometer-sized Fe(3)O(4) colloids (so-called magnetoliposomes). In comparison with the lipid-depleted free enzyme, both the activity and the enzymatic stability of the complexes, stored at 4 degrees C, were considerably enhanced. These beneficial properties of magnetoproteoliposomes have been successfully exploited in a magnetically controlled fixed-bed bioreactor, operating in a continuous flow regime. (c) 1996 John Wiley & Sons, Inc.     

Measurement of tooth extraction forces in upper incisors

A new method, applied for the first time in this research, was used for measurement of tooth extraction forces. The research has been done in a group of 50 examinees to whom the tooth extraction has been done with lower premolar forceps - forceps "13" and in the control group of 54 examinees in whom the tooth extraction has been done with upper incisive forceps - forceps "1". The measurement instrument registered the extraction forces values in both types of forceps. There was no difference in any parameters in these two groups except in used pressure. While using the forceps "13", a significantly lower tooth extraction force was measured than the force measured while using the forceps "1" (p < 0.001). This means that in clinical work we can already apply noticeably less force using the lower premolar forceps for the extraction of the upper incisors (in the moments of rotation up to 70%). These results are meaningful, because they lead to better and improved instrument solutions and working techniques.     

Echocardiographic imaging of tricuspid and pulmonary valve abnormalities in primary ovarian carcinoid tumor

Introduction

The anterior mitral leaflet cleft is an unusual congenital lesion most often encountered in association with other congenital heart defects. The isolated anterior leaflet cleft is quite a rare anomaly and is usually cause of mitral valve regurgitation. The importance of the lesion is that it is often correctable. When feasible, cleft suture and, eventually, annuloplasty are preferable to valve replacement. Echocardiography is the first choice technique in the evaluation of mitral valve disease, providing useful information about valve anatomy and hemodynamic parameters.

Case presentation

We present a case of an isolated anterior mitral leaflet cleft producing moderate-severe mitral regurgitation correctly identified by echocardiography and successfully surgically corrected.

Conclusion

Isolated cleft is a rare aberration, that has to be known in order to be diagnosed. Transthoracic and transesophageal echocardiography is the most useful non invasive technique for cleft diagnosis and to indicate the right surgical correction.