Minimally invasive mitral valve surgery through right anterolateral minithoracotomy

Robotic vs. minimally invasive mitral valve repair: A 5-year comparison of surgical outcomes

BACKGROUND

Minimally invasive mitral valve repair (MVr) is commonly performed. Data on the outcomes of robotic MVr versus nonrobotic minimally invasive MVr are lacking. We sought to compare the short-term and mid-term outcomes of robotic and nonrobotic MVr.

METHODS

We reviewed all patients who underwent robotic MVr (n = 424) or nonrobotic MVr via right mini-thoracotomy (n = 86) at Mayo Clinic, Rochester, MN, from January 2015 to February 2020. Data on baseline and operative characteristics, operative and long-term outcomes were analyzed. Patients were matched 1:1 using propensity scores.

RESULTS

Sixty-nine matched pairs were included in the study. The median age was 59 years (interquartile range [IQR]: 54-69) and 75% (n = 103) were male. Baseline characteristics were similar after matching. Robotic and nonrobotic MVr had similar operative characteristics, except that robotic had longer cross-clamp times (57 [48-67] vs. 47 [37-58] min, p < .001) and more P2 resections (83% vs. 68%, p = .05) compared to nonrobotic MVr. There was no difference in operative outcomes between groups. Hospital stay was shorter after robotic MVr (4 [3-4] vs. 4 [4-6] days, p = .003). After a median follow-up of 3.3 years (IQR, 2.1-4.5), there was no mortality in either group, and there was no difference in freedom from mitral valve reoperations between robotic and nonrobotic MVr (5 years: 97.1% vs. 95.7%, p = .63). Follow-up echocardiogram analysis predicted excellent freedom from recurrent moderate-or-severe mitral regurgitation at 3 years after robotic and nonrobotic MVr (90% vs. 92%, p = .18, respectively).

CONCLUSIONS

Both short-term and mid-term outcomes of robotic and nonrobotic minimally invasive mitral repair surgery are comparable.

Mitral Valve Surgery via Upper Ministernotomy: Single-Centre Experience in More than 400 Patients

Background: Minimally invasive mitral valve (MV) surgery has emerged as an alternative to conventional sternotomy aiming to decrease surgical trauma. The aim of the study was to describe our experience with minimally invasive MV surgery through partial upper sternotomy (PUS) regarding short- and long-term outcomes. Methods: From January 2004 through March 2014, 419 patients with a median age of 58.9 years (interquartile range 18.7; 31.7% females) underwent isolated primary MV surgery using PUS. Myxomatous degenerative MV disease was the predominant pathology (77%). The patients’ mean EuroSCORE II risk profile was 3.9 ± 3.6%. Results: Mitral valve repair was performed in 384 patients (91.6%) and replacement in 35 patients (8.4%). Thirty-day mortality was 3.1%. In total, 29 (6.9%) deaths occurred during the follow-up. The overall estimated survival at 1, 5, and 10 years was 93.1 ± 1.3%, 87.1 ± 1.9%, and 81.1 ± 3.4%. Reoperation was necessary in 14 (3.3%) patients. The overall freedom from MV reoperation at 1, 5, and 10 years was 98.2 ± 0.7%, 96.1 ± 1.2%, and 86.7 ± 6.7% and the overall freedom from recurrent MV regurgitation > grade 2 in repaired valves at 1, 5, and 10 years was 98.8 ± 0.6%, 98.8 ± 0.6%, and 94.6 ± 3.3%. Conclusions: Minimally invasive MV surgery via PUS can be performed with particularly good early and late results. Thus, the PUS approach with the use of standard surgical instruments and cannulation techniques can be a valuable option for the MV surgery either in patients contraindicated or not suitable to minithoracotomy.

Intermediate-Term Results of 505 Consecutive Minithoracotomy Mitral Valve Procedures

Background

Patient demand for less invasive surgery and interest in avoiding sternotomy has led to the increased use of the minithoracotomy for mitral valve surgery. Although the feasibility of this approach has been established, few data are available regarding intermediate-term results.

Methods

A total of 505 consecutive minithoracotomy mitral valve procedures performed between 1996 and 2004 were analyzed. Procedures were mitral replacement (191/505, 38%) and repair (314/505, 62%). Concomitant cardiac procedures were performed in 78 cases (13%) (maze 36, tricuspid 29, atrial septal defect/patent foramen ovale 13) and reoperation in 92 cases (18%). Arterial cannulation was ascending aorta in 403 cases (80%), femoral in 101 cases (20%), and axillary in 1 case (< 1%). An endoluminal aortic clamp was used in 406 cases (80%), an external clamp was used in 19 cases (4%), and 80 procedures (16%) were performed with ventricular fibrillation. Robotic assistance was used in 12 cases (2%).

Results

Mean patient age was 58.7 years (range 18–90 years). Median follow-up was 3.1 years. Operative mortality was 4 of 505 cases (<1%). Major complications included stroke in 7 cases (1%) and reoperation for bleeding in 18 cases (4%); there were no cases of mediastinitis. Late complications included chronic aortic dissection in 1 case (<1%) and mitral reoperation in 13 cases (3%) (subacute bacterial endocarditis 6, failed repair 2, other 5). Five-year survival was (83% ± 2%) and freedom from mitral reoperation was (96% ± 1%). Follow-up echocardiograms were available in 246 of 314 cases (78%) mitral repairs and mean mitral regurgitation grade was 1 ± 1. Mitral regurgitation was grade 3–4+ in 14 of 246 cases (6%) (subacute bacterial endocarditis 4, low ejection fraction 5, other 5). Five-year freedom from 3–4+ mitral regurgitation was 89% ± 3%.

Conclusions

Mitral valve surgery via minithoracotomy can be performed safely with a low perioperative complication rate. A durable technical result and excellent long-term survival can be expected.

Minimally Invasive Cardiac Surgery in China: Multi-Center Experience

BACKGROUND To the best of our knowledge, there is no nationwide data available on the development of minimally invasive cardiac surgery (MICS) in China. The purpose of this study was to report the results of MICS in 6 experienced centers in China. MATERIAL AND METHODS From September 2014 to July 2016, 1241 patients with cardiac conditions who underwent MICS procedures were randomly enrolled in 6 centers in China, and those patients were randomly selected for inclusion in this study. The MICS procedures were defined as any cardiac surgery performed through a less invasive incision, rather than a complete median sternotomy, mainly including mini-incision surgery (400, 32.2%), video-assisted approach (265, 21.3%), completely thoracoscopic approach without robotic assistance (504, 40.6%), and robotic procedure (55, 4.4%). RESULTS The 5 most common in-hospital complications were respiratory failure (28, 2.3%), reoperation for all reasons (19, 1.5%), renal failure (11, 0.9%), heart failure (9, 0.7%), and stroke (6, 0.5%). The multivariate logistic regression analysis results showed that cardiopulmonary bypass (CPB) time (P=0.033), aortic cross-clamp time (P=0.003), cannulation approach (P=0.010), and left ventricular ejection fraction (LVEF) (P=0.003) at baseline were all significant risk factors of any in-hospital complication of MICS procedures. CONCLUSIONS From our experience, minimally invasive cardiac approaches are safe and reproducible, with acceptable CPB and aortic cross-clamp time duration and low mortality.

Clinical Safety and Effectiveness of Endoaortic as Compared to Transthoracic Clamp for Small Thoracotomy Mitral Valve Surgery: Meta-Analysis of Observational Studies

Controversies remain on the increased rate of neurological events after small thoracotomy mitral valve surgery attributed to endoaortic balloon occlusion (EABO). Systematic literature search of databases identified 17 studies enrolling 6,643 patients comparing safety and effectiveness of EABO versus transthoracic clamp. In a meta-analysis, there was no difference in occurrence of cerebrovascular events, all-cause mortality, and kidney injury. EABO was associated with a significantly higher risk of iatrogenic aortic dissection (0.93% versus 0.13%; risk ratio, 4.67; 95% confidence interval, 1.62 to 13.49; p = 0.004) and a trend toward longer operative times. The data is limited to observational studies.

An Alternative, Less Invasive Approach to Median Sternotomy for Cardiac Operations in Adults: Right Infra-Axillary Minithoracotomy

We compared the use of right infra-axillary minithoracotomy and conventional median sternotomy in direct open-heart surgery in 59 adults undergoing elective surgery for mitral valve stenosis, mitral valve disease, atrial septal defect repair, left atrial myxoma excision or mitral and tricuspid valve disease. Patients were randomized to the infra-axillary minithoracotomy group (Group A; n = 29) or the median sternotomy group (Group B; n = 30). Post-operative outcomes (post-operative bleeding; cross-clamp time; length of hospital and intensive care unit stays; and postoperative blood transfusion and analgesic requirements) were recorded and compared; they were found to be significantly lower in Group A than Group B. We concluded that right infra-axillary minithoracotomy is less invasive and can be used safely in adults as an alternative approach to conventional median sternotomy for some cardiac operations. Further multicentre studies in adults are now needed.

Anterolateral minithoracotomy versus median sternotomy for mitral valve disease: a meta-analysis

OBJECTIVE

Mitral valve disease tends to be treated with anterolateral minithoracotomy (ALMT) rather than median sternotomy (MS), as ALMT uses progressively smaller incisions to promote better cosmetic outcomes. This meta-analysis quantifies the effects of ALMT on surgical parameters and post-operative outcomes compared with MS.

METHODS

One randomized controlled study and four case-control studies, published in English from January 1996 to January 2013, were identified and evaluated.

RESULTS

ALMT showed a significantly longer cardiopulmonary bypass time (P=0.001) and aortic cross-clamp time (P=0.05) compared with MS. However, the benefits of ALMT were evident as demonstrated by a shorter length of hospital stay (P<0.00001). According to operative complications, the onset of new arrhythmias following ALMT decreased significantly as compared with MS (P=0.05); however, the incidence of peri-operative mortality (P=0.62), re-operation for bleeding (P=0.37), neurologic events (P=0.77), myocardial infarction (P=0.84), gastrointestinal complications (P=0.89), and renal insufficiency (P=0.67) were similar to these of MS. Long-term follow-up data were also examined, and revealed equivalent survival and freedom from mitral valve events.

CONCLUSIONS

Current clinical data suggest that ALMT is a safe and effective alternative to the conventional approach and is associated with better short-term outcomes and a trend towards longer survival.

Percutaneous superior vena cava drainage during minimally invasive mitral valve surgery: a randomized, crossover study

OBJECTIVE

Minimally invasive techniques commonly are applied to mitral valve surgery; however, there has been little research investigating the optimal methods of cardiopulmonary bypass for the right minithoracotomy approach. Controversy exists as to whether a percutaneous superior vena cava drainage cannula (PSVC) is necessary during these operations. The authors, therefore, sought to determine the effect of using a percutaneous superior vena cava catheter on brain near-infrared spectroscopy, blood lactate levels, hemodynamics and surgical parameters.

DESIGN

Randomized, blinded, crossover trial.

SETTING

Tertiary care university hospital.

PARTICIPANTS

Patients undergoing minimally invasive mitral valve surgery via a right minithoracotomy.

INTERVENTIONS

Twenty minutes of either clamped or unclamped percutaneous superior vena cava neck catheter drainage, during mitral valve repair.

MEASUREMENT AND MAIN RESULTS

For the primary outcome of brain near-infrared spectroscopy, there were no differences between the two groups (percutaneous superior vena cava clamped 55.0%±11.6% versus unclamped 56.1%±10.2%) (p = 0.283). For the secondary outcomes pH (clamped 7.35±0.05 versus unclamped 7.37±0.05 p = 0.015), surgical score (clamped 1.96±1.14 versus unclamped 1.22±0.51 p = 0.002) and CVP (clamped 11.6 mmHg±4.8 mmHg versus unclamped 6.1 mmHg±6.1 mmHg p<0.001) were significantly different.

CONCLUSIONS

The use of a percutaneous superior vena cava drainage improved surgical visualization and lowered CVP, but had no effect on brain near infrared spectroscopy during minimally invasive mitral valve surgery. (ClinicalTrials.gov Identifier: NCT01166841).

Perfusion techniques for minimally invasive valve procedures

In this paper, we present, in detail, the simplified perfusion technique that we have adopted since January 2009 and that we have utilized in 200 cases for cardiac minimally invasive valvular procedures that were performed through a right lateral mini-thoracotomy in the 3(rd)-4(th) intercostal space. Cardiopulmonary bypass was achieved by means of the direct cannulation of the ascending aorta and the insertion of a percutaneous venous cannula in the femoral vein. A flexible aortic cross-clamp was applied through the skin incision and cardioplegic arrest was obtained with the antegrade delivery of a crystalloid solution. Gravity drainage was enhanced by vacuum-assisted aspiration. There were no technical complications related to this perfusion technique that we have adopted in minimally invasive surgical procedures.

Minimally invasive heart valve surgery: already established in clinical routine?

Cardiac valve replacement with the need for open heart surgery still has the highest morbidity and mortality rates among routine cardiac surgery, with the exception of aortic aneurysm repair and surgery for congenital heart defects. Reducing invasiveness is a desirable goal, and different strategies and approaches have been used to achieve this with valve repair or replacement less invasive. Despite the good results reported with minimally invasive techniques, time on extracorporal circulation is always longer compared with the conventional procedures. Since these techniques do not reduce real invasiveness but rather improve the cosmetic results, minimal-access surgery would be a better nomenclature. With the exception of patients at a high risk for sternal infections or redo heart operations, a reduction in postoperative morbidity by the avoidance of a median sternotomy is not yet definitely proven. Meanwhile, most surgeons comply with the demand for minimally invasive surgery posed by patients by reducing the length of the incision in aortic valve replacement and by using a right anterolateral approach with a limited incision for mitral valve operations. However, the use of endoscopic or robotic devices is limited to a few centers, and has not yet found its way into clinical routine. Nonetheless, minimally invasive or minimal-access surgery is now established in many centers, and patients should always be informed of these techniques. When this information is provided objectively and patient selection is carried out accurately, these alternative approaches can help to improve postoperative convalescence.

Experience with a minimally invasive approach to combined valve surgery and coronary artery bypass grafting through bilateral thoracotomies

BACKGROUND

Minimally invasive coronary artery bypass grafting (MICS-CABG) and minimally invasive valve surgery (MIVS) have been used independently to manage occlusive coronary artery disease and valvular diseases, respectively. We present 12 patients who underwent combined MICS-CABG and MIVS via bilateral mini-thoracotomies.

METHODS

We retrospectively reviewed 116 consecutive valve/CABG operations by a single surgeon and compared the outcomes obtained via sternotomy with those obtained via bilateral minithoracotomies.

RESULTS

Six patients in the MIVS group underwent aortic valve replacement (sternotomy group, n = 70), 3 patients underwent mitral valve repair (sternotomy group, n = 9), and 3 underwent mitral valve replacement (sternotomy group, n = 25). The minimally invasive valve surgeries were combined with MICS-CABG for single- (n = 2), double- (n = 9), and triple-vessel (n = 1) coronary artery disease in a single operation. The mean SD duration of cardiopulmonary bypass was 164 ± 44.6 minutes (mean time via sternotomy, 152 ± 50.5 minutes; P = .4146), and the mean aortic cross-clamp time was 87.8 ± 22.1 minutes (mean time via sternotomy, 105 ± 39.8 minutes; P = .1455). The use of perioperative blood transfusions averaged to 2.3 ± 5.6 units (mean usage via sternotomy, 2.7 ± 4.9 units; P = .8326). There were no conversions to sternotomy in the minimally invasive group. Patients in the minimally invasive group were extubated earlier (24 ± 11 hours; sternotomy group, 40 ± 61 hours; P = .3684) and discharged earlier (7 ± 4 days) than patients who underwent median sternotomy (9 ± 10 days; P = .4027).

CONCLUSION

MICS-CABG combined with MIVS via bilateral minithoracotomies yielded short-term results comparable to those for CABG and valve repair via median sternotomy. There were no operative mortalities or reoperations. The possible advantages of the minimally invasive approach included earlier extubation and earlier discharge from the hospital. Combined CABG and valve surgery can be safely performed via bilateral thoracotomies.

Atrial septal defect closure: comparison of vertical axillary minithoracotomy and median sternotomy

BACKGROUND

This study aims to evaluate whether or not the method of right vertical axillary minithoracotomy (RVAM) is preferable to and as reliable as conventional sternotomy surgery, and also assesses its cosmetic results.

METHODS

Thirty-three patients (7 males, 26 females) with atrial septal defect were admitted to the Cardiovascular Surgery Clinic of Cukurova University from December 2005 until January 2010. The patients' ages ranged from 3 to 22. Patients who underwent vertical axillary minithracotomy were assigned to group I, and those undergoing conventional sternotomy, to group II. Group I and group II were compared with regard to the preoperative, perioperative and postoperative variables. Group I included 12 females and 4 males with an average age of 16.5±9.7. Group II comprised 14 female and 3 male patients with an average age of 18.5±9.8 showing similar features and pathologies. The cases were in Class I-II according to the New York Heart Association (NYHA) Classification, and patients with other cardiac and systemic problems were not included in the study. The ratio of the systemic blood flow to the pulmonary blood flow (Qp/Qs) was 1.8±0.2. The average pulmonary artery pressure was 35±10 mmHg. Following the diagnosis, performing elective surgery was planned.

RESULTS

No significant difference was detected in the average time of the patients' extraportal circulation, cross-clamp and surgery (p>0.05). In the early postoperative period of the cases, the duration of mechanical ventilator support, the drainage volume in the first 24 hours, and the hospitalization time in the intensive care unit were similar (p>0.05). Postoperative pains were evaluated together with narcotic analgesics taken intravenously or orally. While 7 cases (43.7%) in group I needed postoperative analgesics, 12 cases (70.6%) in group II needed them. No mortality or major morbidity has occurred in the patients. The incision style and sizes in all of the patients undergoing RVAM were preserved as they were at the beginning. Furthermore, the patients of group I were mobilized more quickly than the patients of group II. The patients of group I were quite pleased with the psychological and cosmetic results. No residual defects have been found in the early postoperative period and after the end of the follow-up periods. All of the patients achieved functional capacity per NYHA. No deformation of breast growth has been detected during 18 months of follow-up for the group I patients, who underwent RVAM.

CONCLUSION

To conclude, the repair of atrial septal defect by RVAM, apart from the limited working zone for the surgeon in these pathologies as compared to sternotomymay be considered in terms of the outcomes, and early and late complications. And this has accounted for less need of analgesics and better cosmetic results in recent years.

A quantitative and automatic echographic method for real-time localization of endovascular devices

Current imaging methods for catheter position monitoring during minimally invasive surgery do not provide an effective support to surgeons, often resulting in the choice of more invasive procedures. This study was conducted to demonstrate the feasibility of non-ionizing monitoring of endovascular devices through embedded quantitative ultrasound (QUS) methods, providing catheter self-localization with respect to selected anatomical structures. QUS-based algorithms for real-time automatic tracking of device position were developed and validated on in vitro and ex vivo phantoms. A trans-esophageal ultrasound probe was adapted to simulate an endovascular device equipped with an intravascular ultrasound probe. B-mode images were acquired and processed in real time by means of a new algorithm for accurate measurement of device position. After off-line verification, automatic position calculation was found to be correct in 96% and 94% of computed frames in the in vitro and ex vivo phantoms, respectively. The average errors of distance measurements (bias ± 2SD) in a 41-step 10-cm-long parabolic pathway were 0.76 ± 3.75 mm or 0.52 ± 3.20 mm, depending on algorithm implementations. Our results showed the effectiveness of QUS-based tracking algorithms for real-time automatic calculation and display of endovascular system position. The method, validated for the case of an endoclamp balloon catheter, can be easily extended to most endovascular surgical systems.

Surgical treatment of double and triple heart valve disease through a limited single-access right minithoracotomy

Heart valve disease can be extensive and may include double (mitral-aortic, mitral-tricuspid), or triple (mitral, aortic, and tricuspid) valvular regurgitation. The surgical correction of significant valvular regurgitation usually consists of the repair or replacement of all valves affected by a pathologic process. The median full-length sternotomy still serves as a classic approach for single, double, and triple valve operations in most patients. Here, we present a minimally invasive approach for the surgery of double and triple heart valve disease through a limited single-access right minithoracotomy in the 3rd intercostal space, with central aortic and percutaneous venous cannulation. A total of 48 double valve procedures were performed in our department using this technique. The minimally invasive approach through a right single-access thoracotomy has become our choice for all isolated mitral valve, and for most isolated aortic valve, replacement procedures. Triple valve surgery was performed in six cases and was feasible in all selected patients.

Right inframammary mini-thoracotomy approach to the mitral valve in women with breast implants

OBJECTIVE

: Minimally invasive cardiac surgery in patients with breast implants is challenging. Obtaining access to cardiac structures without injuring the prosthesis and at the same time maintaining cosmesis is of particular concern in these patients. Mitral valve surgery can be performed using a right mini-inframammary thoracotomy in female patients with breast implants. We describe our experience with this approach to preserve the cosmetic results of previous breast augmentation.

METHODS

: Six female patients with previous breast implantation presented for isolated mitral valve surgery for degenerative disease. Surgery was performed through an inframammary incision, in most cases using the previous surgical incision from breast implantation. Peripheral cannulation was used for cardiopulmonary bypass. The breast prosthesis was explanted through a 6-cm skin incision, and then the mitral valve was approached through a right mini anterior thoracotomy. At the end of mitral surgery, the implant was replaced.

RESULTS

: All patients had satisfactory outcomes. The mitral valve was repaired in five patients and replaced in one patient. Average length of stay was 5.3 days (range, 4-8 days). There were no conversions to median sternotomy. There were no bleeding complications. There were no wound complications or implant infections. Cosmesis was preserved.

CONCLUSIONS

: Our experience with this approach has allowed both mitral valve repair and replacement at the same time preserving cosmetic results. This minimally invasive technique may also have applications in performing atrial septal defect closure, Maze procedures for atrial fibrillation, and tricuspid valve surgery in patients with breast implants.

Triple heart valve surgery through a right antero-lateral minithoracotomy

Triple valve surgery remains a complex intervention, with prolonged cardiopulmonary bypass (CPB) and cross-clamp times. A median sternotomy is the standard approach in the surgical treatment of multiple valve disease. In this report, we attempt to describe our approach for the correction of the triple heart valve disease through a right antero-lateral minithoracotomy, because avoiding sternotomy can bring less wound infections, faster recovery and a shorter hospital stay. The right minithoracotomy in the 3rd intercostal space was applied in two patients and a feasibility of either repair or replacement with a good field exposure to access the aortic, mitral and tricuspid valves without any particular difficulties was verified.

Minimally invasive mitral valve surgery via right minithoracotomy

From early experience in cardiac surgery on the mitral valve, access was gained in different ways: through left and right antero-lateral extended thoracotomy for closed and correspondingly for open mitral commissurotomy, from right parasternal access with rib resection, and via median sternotomy. Median sternotomy remains the most common approach for mitral valve procedures, such as replacement or repair, allowing good visualisation, exposure and working field. Applying the largely spread access as median sternotomy, surgeons always wanted to overcome the necessity of large incisions, get a better surgical view, to dissect with better respect to structural integrity and have better aesthetic results. Enhanced understanding of surgical bases and technological development sourced a breakthrough in minimally-invasive approach for mitral valve surgery, offering several advantages such as less postoperative pain, lower morbidity and mortality, faster recovery and shorter hospital stay. In an effort to share the institutional experience in less invasive surgery, this article demonstrates our approach in mitral valve repair through a right minithoracotomy in the 3rd or 4th intercostal space.

Evaluation of a novel atrial retractor for exposure of the mitral valve in a porcine model

OBJECTIVES

To describe a novel atrial retractor and compare 2 methods of intraoperative left atrial retraction for minimally invasive mitral valve repair.

METHODS

Left atrial retraction was performed on 5 swine cadavers to evaluate performance (percent of mitral valve annulus accessible), complications encountered, ease of use, and surgical time for the minimally invasive atrial retractor and a HeartPort atrial retractor.

RESULTS

Estimated accessibilities were 93.0% (standard error = 3.2) and 92.7% (standard error = 3.3) for the HeartPort and minimally invasive atrial retractor retractors, respectively, with a difference of 0.3% (standard error = 2.2%, P = .8832, df = 34). Tissue damage occurred in 1 case for the minimally invasive atrial retractor and 2 cases for the HeartPort retractor. The mean surgical times for retractor placement and mitral valve annulus exposure were 107.4 and 39.2 seconds for the HeartPort and minimally invasive atrial retractor retractors, respectively, with a difference of 68.2 seconds (P = .0092, df = 4).

CONCLUSIONS

The minimally invasive atrial retractor is a suitable alternative for atrial retraction compared with standard techniques of retraction. It provides comparable exposure of the mitral valve annulus, is less time consuming to place, provides subjectively more working volume within the left atrium, and has the advantage of minimal atriotomy incision length and customizable retraction.

Minimally invasive technology for mitral valve surgery via left thoracotomy: experience with forty cases

BACKGROUND

Recent evolution of minimally invasive technology has expanded the application of the right thoracotomy approach for mitral valve surgery. These same technological advances have also made the left posterior minithoracotomy approach attractive in complex mitral procedures.

METHODS

From 1996 to 2003, 921 isolated mitral valve procedures were performed without sternotomy; 40 (4.3%) of these were performed via left posterior minithoracotomy. In the left posterior minithoracotomy group, ages ranged from 18 to 84 years; 36 patients had had previous cardiac surgery (9 on > or =2 occasions). Other factors precluding right thoracotomy included mastectomy/radiation and pectus excavatum.

RESULTS

Arterial perfusion was via femoral artery (n = 26) or descending aorta (n = 14); long femoral venous cannulas with vacuum-assisted drainage were used in 39 procedures. Two patients had direct aortic crossclamping, 18 had hypothermic fibrillation, and 20 had balloon endoaortic occlusion. The mean crossclamp and bypass times were 81.9 and 117.2 minutes, respectively. Hospital mortality was 5.0% (2/40); both deaths occurred in octogenarians. There were no injuries to bypass grafts or conversions to sternotomy. Complications included perioperative stroke (2/40; 5.0%), bleeding (2/40; 5.0%), and respiratory failure (1/40; 2.5%); 28 patients (70%) had no postoperative complications. There was no incidence of perioperative myocardial infarction, renal failure, sepsis, or wound infection. The median length of stay was 7 days.

CONCLUSIONS

Advances in minimally invasive cardiac surgery technology are readily adaptable to a left-sided minithoracotomy approach to the mitral valve. The left posterior minithoracotomy approach is a valuable option in complicated reoperative mitral procedures with acceptable perioperative morbidity and mortality.

Redo mitral valve surgery using the port-access system

Redo mitral valve surgery is hazardous, hence we explored an alternative approach using a port-access system that avoids reentry. Between October 1997 and December 2000, 32 patients underwent mitral reoperation using the system. All patients had previous cardiac operations. This procedure consisted of a right anterolateral minithoracotomy and femorofemoral cannulation using special port-access instruments and endoaortic clamping in 24 patients or direct transthoracic sliding-rod aortic clamping in 8. The valve disease was of rheumatic etiology in 28 patients and degenerative in 4. The valve was replaced in 31 cases and a paravalvular leak after mitral valve replacement was closed in 1. In 2 cases, the tricuspid valve was repaired along with mitral valve replacement. Mean total operating time was 4.5 +/- 1.2 hours, cardiopulmonary bypass time 162 +/- 72 minutes, and aortic crossclamp time 62 +/- 21 minutes. There was no mortality, and mean stay in the intensive care unit was 22 +/- 7 hours and hospital stay 6.4 +/- 1.2 days. Postoperative blood transfusion was required in 12 patients. In view of the favorable results, we recommend using the port-access system as a standard approach for mitral reoperation.

Minimally invasive mitral valve surgery: a 6-year experience with 714 patients

BACKGROUND

This study analyzes a single institutional experience with minimally invasive mitral valve operations of 6 years, reviewing short-term morbidity and mortality and long-term echocardiographic follow-up data.

METHODS

Seven hundred fourteen consecutive patients had minimally invasive mitral valve procedures between November 1995 and November 2001; concomitant procedures included 91 multiple valves and 18 coronary artery bypass grafts. Of these 714 patients, 561 patients had isolated mitral valve operations (375 repairs, 186 replacements). Mean age was 58.3 years (range, 14 to 96 years; 30.1% > 70 years), and 15.4% of patients had previous cardiac operations. Arterial cannulation was femoral in 79.0% and central in 21%, with the port access balloon endo-occlusion used in 82.3%. Cardioplegia was transjugular retrograde (54.1%) or antegrade (29.4%). Right anterior minithoracotomy was used in 96.6% and left posterior minithoracotomy in 2.2%.

RESULTS

Hospital mortality for primary isolated mitral valve repair was 1.1% and 5.8% for isolated mitral valve replacement. Overall hospital mortality was 4.2% (30 of 714). Mean cross-clamp time was 92 minutes and mean cardiopulmonary bypass time was 127 minutes. Postoperatively, median ventilation time was 11 hours, intensive care unit time was 19 hours, and total hospital stay was 6 days. Complications for all patients included permanent neurologic deficit (2.9%), aortic dissection (0.3%); there was no mediastinal infection (0.0%). Follow-up echocardiography demonstrated 89.1% of the repair patients had only trace or no residual mitral insufficiency.

CONCLUSIONS

This study demonstrates that the minimally invasive port access approach to mitral valve operations is reproducible with low perioperative morbidity and mortality and with late outcomes that are equivalent to conventional operations.

An alternative surgical approach to facilitate minimally invasive mitral valve surgery

An alternative approach to minimally invasive mitral valve surgery is described that permits direct great vessel cannulation and direct aortic clamp occlusion through a 6- to 8-cm incision. This approach reduces the complexity of the procedure, and hopefully, will contribute to more widespread adoption of less invasive techniques in mitral valve surgery.