Review of transapical off-pump mitral valve intervention with NeoChord implantation

Closing the care gap: combining enhanced recovery with minimally invasive valve surgery

PURPOSE OF REVIEW

Patients with advanced age and frailty require interventions for structural heart disease at an increasing rate. These patients typically experience higher rates of postoperative morbidity, mortality and prolonged hospital length of stay, loss of independence as well as associated increased costs to the healthcare system. Therefore, it is becoming critically important to raise awareness and develop strategies to improve clinical outcomes in the contemporary, high-risk patient population undergoing cardiacprocedures.

RECENT FINDINGS

Percutaneous options for structural heart disease have dramatically improved the therapeutic options for some older, frail, high-risk patients; however, others may still require cardiac surgery. Minimally invasive techniques can reduce some of the physiologic burden experienced by patients undergoing surgery and improve recovery. Enhanced Recovery After Cardiac Surgery (ERAS Cardiac) is a comprehensive, interdisciplinary, evidence-based approach to perioperative care. It has been shown to improve recovery and patient satisfaction while reducing complications and length of stay.

SUMMARY

Combining minimally invasive cardiac surgery with enhanced recovery protocols may result in improved patient outcomes for a patient population at high risk of morbidity and mortality following cardiac surgery.

Minimally Invasive Approaches to Mitral Valve Surgery: Where Are We Now? A Narrative Review

Minimally invasive mitral valve surgery (MiMVS) has been increasing in prevalence. This review focuses on the approaches, clinical outcomes, and patient selection for MiMVS. There are 4 minimally invasive approaches to the mitral valve: right mini-thoracotomy (including video-assisted and fully endoscopic), robotic mitral surgery, and transapical beating heart off-pump neochordal repair. Advantages over conventional surgery include less blood loss and transfusion, improved postoperative mobility, shorter length of stay, less postoperative atrial fibrillation, fewer surgical site infections, and improved cosmesis. This range of minimally invasive techniques will continue to evolve, providing options that are tailored for different patient populations.

Microinvasive mitral valve repair with transapical mitral neochordae implantation

Microinvasive cardiac surgery includes procedures performed off-pump, on the beating heart, with limited or absent skin incision, and those that rely on live imaging techniques. Transapical off-pump beating heart neochordae implantation allows the repair of severe mitral valve regurgitation due to leaflet prolapse or flail with live three-dimensional echo guidance. This procedure has shown good results for up to 5 years and can be considered as a valid alternative to conventional surgery in selected patients with high prediction of success based on clinical and anatomical considerations. The aim of this review is to describe the devices, indications, patient screening process, clinical and echocardiographic results, and future perspectives of this procedure.

Echocardiographic and clinical outcomes following beating heart NeoChord DS1000 mitral valve repair: a single centre case series

Background

The NeoChord DS1000 system implants artificial neochords transapically, through a left mini-thoracotomy to treat degenerative mitral valve regurgitation (MR). Performed without cardiopulmonary bypass, neochord implantation and length adjustment is guided by transesophageal echocardiography. We describe imaging and clinical outcomes for a single center case series using this innovative device platform.

Methods

In this prospective series, all study patients had degenerative MR and were considered for conventional mitral valve surgery. Moderate to high-risk candidates were screened for NeoChord DS1000 eligibility based on echocardiographic criteria. Study criteria included isolated posterior leaflet prolapse, leaflet-to-annulus index greater than 1.2, and coaptation length index greater than 5 mm. Patients with bileaflet prolapse, mitral annular calcification, and ischemic MR were excluded from our early experience.

Results

Ten patients underwent the procedure, including 6 males and 4 females, with a mean age of 76 ± 9.5 years. All patients had severe chronic MR and normal left ventricular function. One patient required conversion to an open procedure for failure to deploy neochords with the device transapically. The median number of NeoChord sets was 3 (IQR 2.3-3.8). Immediate post-procedure (POD#0) degree of MR on echocardiography ranged from mild or less, and on postoperative day 1 (POD#1) from moderate or less. Average length of coaptation was 0.85 ± 0.21 cm and average depth of coaptation was 0.72 ± 0.15 cm. At 1-month follow-up echocardiography, MR was graded from trivial to moderate and left ventricular inner diameter dimensions decreased from an average of 5.4 ± 0.4 cm to 4.6 ± 0.3 cm. None of the patients who had successful NeoChord implantation required blood products. There was 1 perioperative stroke with no residual deficits. There were no device-related complications or serious adverse events. The median length of hospital stay was 3 (IQR 2.3-10) days. 30-day and 6-weeks postoperative mortality and readmission rates were 0%.

Conclusion

We report the first Canadian case series using the NeoChord DS1000 system for off-pump, transapical, beating heart mitral valve repair, through a left mini-thoracotomy. The early surgical outcomes suggest this approach is feasible, safe, and effective in reducing MR. This novel procedure has the advantage of offering a minimally invasive, off-pump option for select patients with high surgical risk.

Functional evaluation of the diaphragm with a noninvasive test

Cardiac surgery with median sternotomy causes iatrogenic damage to the function of the diaphragm muscle that is both temporary and permanent. Myocardial infarction itself causes diaphragmatic genetic alterations, which lead the muscle to nonphysiological adaptation. The respiratory muscle area plays several roles in maintaining both physical and mental health, as well as in maximizing recovery after a cardiac event. The evaluation of the diaphragm is a fundamental step in the therapeutic process, including the use of instruments such as ultrasound, magnetic resonance imaging (MRI), and computed axial tomography (CT). This article reviews the neurophysiological relationships of the diaphragm muscle and the symptoms of diaphragmatic contractile dysfunction. The authors discuss a scientific basis for the use of a new noninstrumental diaphragmatic test in the hope of stimulating research.