Minimally Invasive Valve Surgery: When Less Is More

Aortic Valve Replacement Via Right Anterior Mini-Thoracotomy: the Conventional Procedure Performed Through a Smaller Incision

Minimally invasive aortic valve replacement has gained consent due to its good results in terms of minimized surgical trauma, faster rehabilitation, pain control and patient compliance. In our experience, we have tried to replicate the conventional and gold standard approach through a smaller incision. Sparing the right internal thoracic artery, avoiding rib fractures and performing total central cannulation is important to make this procedure minimally invasive from a biological point of view too. In addition, the total central cannulation is pivotal to simplify perfusion and drainage. Moreover, a complete step-by-step procedure optimization and-when possible-the use of sutureless prosthesis help to reduce the cross-clamping and perfusion times. After more than 1000 right anterior thoracotomy (RAT) aortic valve replacements, we have found tips and tricks to make our technique more effective.

Video-Assisted Minimally Invasive Aortic Valve Replacement Through Right Anterior Minithoracotomy for All Comers With Aortic Valve Disease

OBJECTIVE

Right anterior minithoracotomy is a promising technique for aortic valve replacement and has shown excellent results in terms of mortality and morbidity. Against this background, we analyzed our institutional experience in this technique during the last 3 years.

METHODS

Between April 2017 and March 2019, 513 consecutive all comers with aortic valve disease underwent video-assisted minimally invasive aortic valve replacement through a 3-cm skin incision as right anterior minithoracotomy at our institution. A camera and automatic fastener technology were used for the valve implantation in all patients. Clinical data were prospectively entered into our institutional database.

RESULTS

Cardiopulmonary bypass time accounted for 68 ± 24 min and the myocardial ischemic time 38 ± 12 minutes. Thirty-day mortality and overall mortality was 0.4% (2 patients) and 1.4% (7 patients), respectively. Postoperative cerebrovascular events were noted in 8 patients (1.5%). Intensive care stay and hospital stay were 2 ± 2 and 9 ± 7 days, respectively. Pacemaker implantation, injury of the right internal mammary artery, and conversion to full sternotomy were noted in 7 patients (1.4%), 3 patients (0.6%), and 1 patient (0.2%), respectively. Paravalvular leak need to intervention was noted in 2 patients (0.4%). Rethoracotomy rate was 2% (11 patients). Transient postoperative dialysis was necessary for 14 patients (3%).

CONCLUSIONS

Video-assisted minimally invasive aortic valve replacement through the right anterior minithoracotomy is a safe approach and yields excellent outcomes in high-volume centers. The use of a camera and automatic fastener technology facilitates this procedure.

Initial Experience of Minimally Invasive Concomitant Aortic and Mitral Valve Replacement/Repair at a Tertiary Care Cardiac Centre of a Developing Country

Introduction

Minimally invasive double valve replacement (DVR) surgery through a small transverse anterior thoracotomy is an alternate technique to sternotomy for concomitant aortic and mitral valve (AVR, MVR) surgery. The aim of this study was to evaluate the in-hospital and early outcomes of direct vision minimal invasive double valve surgery (DVMI-DVR) at a tertiary care cardiac center of a developing country.

Methods

This study was conducted at the National Institute of Cardiovascular Diseases Karachi, Pakistan from January 2018 to September 2018. Nineteen consecutive patients undergoing DVMI-DVR for aortic and mitral disease without any prior cardiac surgery were included in this study. For all procedures, access was obtained through small transverse anterior thoracotomy incision with wedge resection (Chaudhry’s Wedge) of sternum opposite to the third and fourth costosternal joints. Patients were observed during their hospital stay and the following variables were observed the length of hospital stay (LOHS), ventilator support, intensive care unit (ICU) stay, pain score, and mortality. The pain score was assessed using the visual analog scale (VAS).

Results

The male/female ratio was 11:8 with a mean age of 35 ± 12 years with mean EuroSCORE of 6.6 ± 3.5%. The mean total bypass time was 129.8 ± 23.83 min (range: 98-181 minutes). The mean mechanical ventilation time was 3.16 ± 1.12 hours (range: 2-6 hours). The mean intensive care unit (ICU) stay was 41.84 ± 8.36 hours. The mean post-operative LOHS was 5.63 ± 1.12 days (range: 4-8 days). We had zero frequency of wound infection and surgical mortality. The mean pain score was 4.32 (on a predefined pain scale of one to nine with a high value indicating severe pain).

Conclusion

Minimally invasive DVR surgery is a safe and reproducible technique with comparable outcomes such as postoperative pain score (4.32 ± 2.05), ventilation time (3.16 ± 1.12 hours), ICU stay (41.84 ± 8.36 hours), and hospital stay (5.63 ± 1.12 days). In terms of mortality, operative times, ICU stay, and hospital stay, the minimally invasive DVR is at least comparable to those achieved with median sternotomy. Further prospective randomized studies are needed to validate our findings.

Comparison of minimally invasive cardiac surgery incisions: Periareolar approach in female patients

Objective:

All innovations in cardiac surgery provide us with new techniques to perform surgery through smaller incisions with less invasive and best cosmetic results. After promising results in minimally invasive cardiac surgery (MICS), pain and cosmetic appearance became important end points, especially for female patients. In the current study, we intended to evaluate the surgical results and cosmetic satisfaction with the periareolar and submammary incision types in cardiac surgery.

Methods:

Ninety-four female patients underwent MICS between July 2013 and March 2018. MICS was performed in 62 patients via periareolar incision and in 32 patients via submammarian incision. We investigated the incision size, wound infection, pain levels by using a postoperative standard pain-level questionnaire, the postoperative scar size, and patient satisfaction using a postoperative patient questionnaire.

Results:

Periareolar incision size was smaller than the submammary incision (Group A: 5.6±0.6 vs. Group B: 6.7±0.8, p=0.001). Four patients from Group B had superficial wound infection (p=0.01). Patients who underwent MICS via periareolar incision and submammary incision had similar pain level (p=0.2). The scar tissue was smaller in size and postoperatively healed better in the following days for the patients with periareolar incision due to the elastic structure of breast tissue. (Group A: 4.3±0.4 vs. Group B: 5.3±0.2, p=0.001).

Conclusion:

Our study suggests that the periareolar approach would be more aesthetic, show better healing, and have a smaller scar size in female patients.

Right Anterior Minithoracotomy for Aortic Valve Replacement: A Widely Applicable, Simple, and Stepwise Approach

Objective

A stepwise approach for right anterior minithoracotomy aortic valve replacement (RAT-AVR), without sutureless valves, special instruments, or preoperative imaging, was developed. We report our experience with this widely applicable, simplified approach.

Methods

Patients with a history of previous chest surgery, documented PVD, severe COPD, LVOT size <2.0 cm, and root size <2.8 cm were excluded. Chest CT was not mandatory. The stepwise surgical approach consists of 1) tolerability of single-lung ventilation; 2) 5-cm long incision on third right anterior ICS; 3) small pericardial opening to localize the aortic valve annular plane by digital palpation; 4) shingling of the correct rib to create a box field; 5) optimizing exposure with stay sutures; 6) femoral or central cannulation with right superior pulmonary vein venting and usual antegrade cardioplegia; 7) performing a standard AVR without adjunct instruments; and 8) reconstructing 1 costochondral cartilage.

Results

Fifty-five patients were operated. The mean age was 68.5 years (SD 10.4); 29.1% were female. Median STS PROM was 1.18 (0.4 to 6.6). Pump and cross-clamp times were 104.8 minutes (SD 27.9) and 73.2 minutes (SD 22.8), respectively. There was no need for a knot pusher. There was 1 conversion, 1 reopening for bleeding, and 1 pacemaker insertion. No patient had a stroke, MI, or death at 30 days. The median LOS was 6 days (3 to 19).

Conclusion

RAT-AVR can be applicable and performed safely in a wide range of patients by adopting a simple, stepwise approach with intraoperative assessment, without the need for special imaging, instrumentation, or advanced training.

A computed tomography-based planning tool for predicting difficulty of minimally invasive aortic valve replacement

OBJECTIVES

Minimally invasive aortic valve replacement has proven its value over the last decade by its significant advancement and reduction in mortality, morbidity and admission time. However, minimally invasive aortic valve replacement is associated with some on-site difficulties such as limited aortic annulus exposure. Currently, computed tomography scans are used to evaluate the anatomical relationship among the intercostal spaces, ascending aorta and aortic valve prior to surgery. We hypothesized that quantitative measurements of access distance and access angle are associated with outcome and access difficulty.

METHODS

We introduce a novel minimally invasive aortic valve replacement planning prototype that allows automatic measurements of access angle, access distance and aortic annulus dimensions. The prototype visualizes these measurements on the chest cage as ISO contours. The association of these measures with outcome parameters such as extracorporeal circulation time, aortic cross-clamping time and access difficulty score was assessed. We included 14 patients who received a new valve by ministernotomy.

RESULTS

The mean access angle was 40.3 ± 5.1°. It was strongly associated with aortic cross-clamping time (Pearson correlation coefficient = 0.60, P = 0.02) and access difficulty score (Spearman's rank correlation coefficient = 0.57, P = 0.03). Access angles were significantly different between easy and difficult access groups (P = 0.03). There was no significant association between access distance and outcome parameters.

CONCLUSIONS

Access angle is strongly associated with procedure complexity. The automated presentation of this measure suggests added value of the prototype in clinical practice.

Minimally Invasive Direct Access Balloon-Expandable Transcatheter Mitral Valve Replacement for Extensive Mitral Annular Calcification after Transcatheter Aortic Valve Replacement

Mitral annular calcification can pose a formidable surgical challenge in the setting of mitral valve replacement for mitral stenosis. Although there are reports of transapical valve-in-valve transcatheter mitral valve replacement in the setting of degenerated bioprosthetic mitral valve replacement, there is less experience with transcatheter mitral valve replacement for mitral annular calcification. This report describes a patient who previously received a transcatheter aortic valve replacement and then subsequently underwent a minimally invasive right thoracotomy for transcatheter mitral valve replacement with a successful result. We discuss technical pearls and operative considerations based on an extensive experience with minimally invasive valve surgery from a right mini-thoracotomy.

Periareolar Access for Minimally Invasive Cardiac Surgery the Brazilian Technique

The periareolar access has been the preferred technique used at our institution for minimally invasive cardiac surgery since 2006. The surgical approach consists of video-assisted minithoracotomy in the 4th right intercostal space, through a periareolar incision. Initially, the technique was restricted to minimally invasive mitral valve surgeries but, due to its feasibility and safety, was soon incorporated as an ideal access for other cardiac pathologies such as tricuspid valve disease, atrial septal defect, atrial fibrillation, and pacemaker leads endocarditis. The technique was performed in 214 patients, and it is associated with excellent aesthetic and functional results, with low morbimortality and no reoperations at long-term follow-up. Here, we describe and support the use of periareolar access as a routine surgical technique for correction of several cardiac pathologies, especially in women.

Right anterolateral thoracotomy: an attractive alternative to repeat sternotomy for high-risk patients undergoing reoperative mitral and tricuspid valve surgery

Background

Reoperative cardiac valve surgery via sternotomy is associated with a substantial morbidity and mortality. This study evaluated the right anterolateral thoracotomy for high-risk patients undergoing mitral and tricuspid valve redo procedures.

Methods

Out of a series of 173 patients undergoing redo cardiac valve surgery, 24 patients were reoperative via the right anterolateral thoracotomy as the high-risk group on the basis of the proximity of the heart and great vessels to the sternum and the presence and location of patent bypass grafts.

Results

In all cases, sternotomy was avoided. The mitral valve and tricuspid valve were replaced in 4 and 19 patients and repaired in 1 and 2 patients, respectively. Moreover, left atrial folding was performed in 5 patients. Mortality was 8.3%. All other patients had uneventful outcomes and normal valve function at follow-up.

Conclusions

Reoperative cardiac valve surgery can be performed safely using the right anterolateral thoracotomy in high-risk patients. It offers enough exposure. It minimizes the need for cardiac dissection, and thus, the risk for injury. Avoiding a high-risk resternotomy increases patients comfort and safety of redo mitral and tricuspid valve surgery.

Electronic supplementary material

The online version of this article (10.1186/s13019-017-0645-x) contains supplementary material, which is available to authorized users.

Respiratory functional status after conventional and minimally invasive aortic valve replacement surgery - a propensity score analysis

Introduction

Reports describing respiratory function of patients after conventional or minimally invasive cardiac surgery are infrequent.

Aim

To compare pulmonary functional status after conventional (AVR) and after minimally invasive, through right anterior minithoracotomy, aortic valve replacement (RT-AVR).

Material and methods

This was an observational analysis of 212 patients scheduled for RT-AVR and 212 for AVR between January 2011 and December 2014 selected using propensity score matching. Respiratory function based on spirometry examinations is presented.

Results

Hospital mortality was 1.4% in RT-AVR and 1.9% in AVR (p = 0.777). Predicted mortality (EuroSCORE II) was 3.2 ±1.1% in RT-AVR and 3.1 ±1.6% in AVR (p = 0.298). Mechanical ventilation time in intensive care unit (ICU) was 7.3 ±3.9 h for RT-AVR and 9.6 ±5.5 h for AVR patients (p < 0.001). Seven days and 1 month after surgery, the reduction of spirometry functional tests was greater in the AVR group than in the RT-AVR group (p < 0.001). Three months after surgery, all spirometry parameters were still reduced and had not returned to preoperative values in both RT-AVR and AVR groups. However, the difference in spirometry values was no longer statistically significant between RT-AVR and AVR groups. Presence of chronic obstructive pulmonary disease and conventional AVR surgical technique were associated with lower values of spirometry parameters after surgery in linear median regression.

Conclusions

Respiratory function based on spirometry examinations was less impaired after minimally invasive RT-AVR surgery in comparison to conventional AVR surgery through median sternotomy.

Respiratory System Function in Patients after Minimally Invasive Aortic Valve Replacement Surgery

Objective

The aim of the study was to comparatively analyze respiratory system function after minimally invasive, through right minithoracotomy aortic valve replacement (RT-AVR) to conventional AVR.

Methods

Analysis of 201 patients scheduled for RT-AVR and 316 for AVR between January 2010 and November 2013. Complications of the respiratory system and pulmonary functional status are presented.

Results

Complications of the respiratory system occurred in 16.8% of AVR and 11.0% of RT-AVR patients ( P = 0.067). The rate of pleural effusions, thoracenteses, pneumonias, or phrenic nerve dysfunctions was not significantly different between groups. Perioperative mortality was 1.9% in AVR and 1.0% in RT-AVR ( P = 0.417). Mechanical ventilation time after surgery was 9.7 ± 5.9 hours for AVR and 7.2 ±3.2 hours for RT-AVR patients ( P < 0.001). Stroke (odds ratio [OR] = 13.4, P = 0.008), increased postoperative blood loss (OR = 9.6, P <0.001), and chronic obstructive pulmonary disease (OR = 7.7, P < 0.001) were risk factors of prolonged mechanical lung ventilation. A week after surgery, the results of most pulmonary function tests were lower in the AVR than in the RT-AVR group ( P < 0.001 was seen for forced expiratory volume in the first second, vital capacity, total lung capacity, maximum inspiratory pressure and maximum expiratory pressure, P = 0.377 was seen for residual volume).

Conclusions

Right anterior aortic valve replacement minithoracotomy surgery with single-lung ventilation did not result in increased rate of respiratory system complications. Spirometry examinations revealed that pulmonary functional status was more impaired after AVR in comparison with RT-AVR surgery.

Effects of heart valve prostheses on phase contrast flow measurements in Cardiovascular Magnetic Resonance - a phantom study

BACKGROUND

Cardiovascular Magnetic Resonance is often used to evaluate patients after heart valve replacement. This study systematically analyses the influence of heart valve prostheses on phase contrast measurements in a phantom trial.

METHODS

Two biological and one mechanical aortic valve prostheses were integrated in a flow phantom. B0 maps and phase contrast measurements were acquired at a 1.5 T MR scanner using conventional gradient-echo sequences in predefined distances to the prostheses. Results were compared to measurements with a synthetic metal-free aortic valve.

RESULTS

The flow results at the level of the prosthesis differed significantly from the reference flow acquired before the level of the prosthesis. The maximum flow miscalculation was 154 ml/s for one of the biological prostheses and 140 ml/s for the mechanical prosthesis. Measurements with the synthetic aortic valve did not show significant deviations. Flow values measured approximately 20 mm distal to the level of the prosthesis agreed with the reference flow for all tested all prostheses.

CONCLUSIONS

The tested heart valve prostheses lead to a significant deviation of the measured flow rates compared to a reference. A distance of 20 mm was effective in our setting to avoid this influence.

Automated CTA based measurements for planning support of minimally invasive aortic valve replacement surgery

Minimally invasive aortic valve replacement (mini-AVR) procedures are a valuable alternative to conventional open heart surgery. Currently, planning of mini-AVR consists of selection of the intercostal space closest to the sinotubular junction on preoperative computer tomography images. We developed an automated algorithm detecting the sinotubular junction (STJ) and intercostal spaces for finding the optimal incision location. The accuracy of the STJ detection was assessed by comparison with manual delineation by measuring the Euclidean distance between the manually and automatically detected points. In all 20 patients, the intercostal spaces were accurately detected. The median distance between automated and manually detected STJ locations was 1.4 [IQR= 0.91-4.7] mm compared to the interobserver variation of 1.0 [IQR= 0.54-1.3] mm. For 60% of patients, the fourth intercostal space was the closest to the STJ. The proposed algorithm is the first automated approach for detecting optimal incision location and has the potential to be implemented in clinical practice for planning of various mini-AVR procedures.

A comparison of minimally invasive and standard aortic valve replacement

OBJECTIVE

The study objective was to compare aortic valve replacement through a right anterior minithoracotomy with aortic valve replacement through a median sternotomy.

METHODS

With propensity score matching, we selected 211 patients after aortic valve replacement through a right anterior minithoracotomy and 211 patients after aortic valve replacement who underwent operation between January 2010 and December 2013. Perioperative outcomes were analyzed, and multivariable logistic regression analysis of risk factors of postoperative morbidity was performed.

RESULTS

For propensity score-matched patients, hospital mortality was 1.0% in the aortic valve replacement through a right anterior minithoracotomy group and 1.4% in the aortic valve replacement group (P = 1.000). Stroke occurred in 0.5% versus 1.4% (P = .615), myocardial infarction occurred in 1.4% versus 1.9% (P = 1.000), and new onset of atrial fibrillation occurred in 12.8% versus 24.2% (P = .003) of patients in the aortic valve replacement through a right anterior minithoracotomy and aortic valve replacement groups, respectively. Postoperative drainage was 353.5 ± 248.6 mL versus 544.3 ± 324.5 mL (P < .001) and blood transfusion was required for 48.8% versus 67.3% (P < .001) of patients in the aortic valve replacement through a right anterior minithoracotomy and aortic valve replacement groups, respectively. Mediastinitis occurred in 2.8% of patients after aortic valve replacement and in 0.0% of patients after aortic valve replacement through a right anterior minithoracotomy surgery (P = .040). Intensive care unit stay (1.3 ± 1.2 days vs 2.6 ± 2.6 days) and hospital stay (5.7 ± 1.6 days vs 8.7 ± 4.4 days) were statistically significantly shorter in the aortic valve replacement through a right anterior minithoracotomy group. Aortic valve replacement through a right anterior minithoracotomy surgery resulted in reduced postoperative morbidity (odds ratio, 0.4; P < .001) and postoperative bleeding and blood transfusion requirements (odds ratio, 0.4; P < .001).

CONCLUSIONS

Aortic valve replacement through a right anterior minithoracotomy surgery resulted in a reduced infection rate, diminished postoperative bleeding and blood transfusion requirements, reduced occurrence of new onset of atrial fibrillation, and shorter intensive care unit and hospital stays.

Health-Related Quality of Life after Minimally Invasive Cardiac Surgery

Objective

Factors influencing health-related quality of life (HRQL) after minimally invasive cardiac surgery have not been well described. We examined the trajectory of HRQL after minimally invasive cardiac surgery and the role of perioperative factors and rhythm on HRQL changes.

Methods

Patients underwent minimally invasive surgical ablation for atrial fibrillation and/or valve surgery (n = 235). Health-related quality of life (SF-12) and clinical status were assessed preoperatively and postoperatively.

Results

Physical summary HRQL (F = 36.2, P < 0.001) and mental summary HRQL (F = 3.2, P = 0.047) improved significantly by 12 months after surgery. Improvement on HRQL peaked at 6 months and plateaued between 6 and 12 months. Physical HRQL was similar to age-based normal values before surgery (P = 0.66) and surpassed norms by 6 months after surgery (P < 0.001). Younger age (r = −0.15, P = 0.02) and lower EuroSCORE II (r = −0.19, P = 0.003) correlated with greater HRQL improvements by 6 months. Only lower EuroSCORE II (r = −0.14, P = 0.04) correlated with greater HRQL improvement by 12 months. Length of stay and major morbidity were not related to HRQL improvement. In surgical ablation patients, restoration of stable sinus rhythm throughout the first 12 months was associated with greater physical HRQL improvement by 6 months compared with patients who had atrial arrhythmia recurrences (change, 5.0 vs. −1.0, P = 0.02).

Conclusions

Health-related quality of life improved significantly after minimally invasive cardiac surgery. These improvements were influenced by age, operative risk, symptoms, and rhythm status. Even patients with HRQL in a normal range before surgery can experience improved HRQL after surgery. Minimally invasive cardiac surgery can offer decreased postoperative complications and also improved HRQL.

Review of Minimally Invasive Aortic Valve Surgery

Minimally invasive aortic valve surgery (MIAVS) has been developed for the last 20 years. The improvements in techniques have permitted cardiac surgeons to perform aortic valve replacement safely and efficiently with minimally incisions. Patients have become older and have multiple comorbidities and this is expected to grow in number. Less-invasive procedures are known to reduce the number of complications, together with smaller incisions, less pain, less blood loss and reduced length of hospital stay. Selective preoperative planning with computed tomography is key to the pre-investigation stage. Hybrid and staged procedures with interventional cardiologists are part of the armamentarium and may be appealing for the present and near future. Despite the nature of demanding procedures and longer learning curve with increased cardiopulmonary bypass times, the outcomes are comparable with same quality as conventional open surgery. Patient recovery is the ultimate purpose of these approaches.