Outcomes of minimally invasive mitral valve surgery in patients with an ejection fraction of 35% or less

Minimally invasive mitral valve repair for functional mitral regurgitation

Systolic heart failure is frequently accompanied by a relevant functional mitral valve regurgitation (FMR) which develops as a direct sequela of the ongoing left ventricular remodelling. The severity of mitral regurgitation is further aggravated by progressive left ventricular enlargement causing leaflet tethering and reduced systolic leaflet movement. The prognosis of such patients is obviously limited by an underlying left ventricular disease, and the correction of secondary FMR has been previously suggested as predominantly ‘cosmetic’ surgery in the setting of ongoing cardiomyopathy. Inferior results of an isolated annuloplasty in type IIIb FMR supported the philosophy of malignant course of progressive cardiomyopathy and resulted in increasingly restricted indications for mitral valve surgery for FMR in the guidelines. The lack of a standardized pathophysiological approach to correct type IIIb FMR led to the development of valve replacement strategy and edge-to-edge catheter-based mitral valve procedures, which became the most frequent procedures in the FMR setting in Europe. Modern mitral valve surgery combines the advantages of 3-dimensional endoscopic minimally invasive surgical approach with standardized subannular repair to address the pathophysiological background of type IIIb FMR. The perioperative results have been significantly improved, and there is a growing evidence of improved long-term stability of subannular repair procedures as compared to isolated annuloplasty. This review article aims to present the current state-of-the-art of the modern mitral valve surgery in FMR and provides suggestions for future trials analysing the potential advantages in these patients.

Minimally invasive mitral valve surgery is associated with excellent resource utilization, cost, and outcomes

OBJECTIVES

Minimally invasive mitral valve surgery (mini-MVR) has numerous associated benefits. However, many studies fail to include greater-risk patients. We hypothesized that a minimally invasive approach in a representative cohort provides excellent outcomes with reduced resource utilization.

METHODS

Mitral valve surgical records from 2011 to 2016 were paired with institutional financial records. Patients were stratified by approach and propensity-score matched to balance preoperative difference. The primary outcomes of interest were resource utilization including cost, discharge to a facility, and readmission.

RESULTS

A total of 478 patients underwent mitral surgery (21% mini-MVR) and were balanced after matching (n = 74 per group), with 18% of patients having nondegenerative mitral disease. Outcomes were excellent with similar rates of major morbidity (9.5% mini-MVR vs 10.8% conventional, P = .78). Mini-MVR cases had lower rates of transfusion (11% vs 27%, P = .01) and shorter ventilator times (3.7 vs 6.0 hours, P < .0001). Mean total hospital cost was equivalent ($49,703 vs $54,970, P = .235) with mini-MVR having lower ancillary ($1645 vs $2652, P = .001) and blood costs ($383 vs $1058, P = .001). These savings were offset by longer surgical times (291 vs 234 minutes, P < .0001) with greater surgical ($7645 vs $7293, P = .0001) and implant costs ($1148 vs $748, P = .03). Rates of discharge to a facility (9.6% vs 16.2%) and readmission (9.6% vs 4.1%) were not statistically different.

CONCLUSIONS

In a real-world cohort, mini-MVR continues to demonstrate excellent results with a favorable resource utilization profile. Greater surgical and implant costs with mini-MVR are offset by decreased transfusions and ancillary needs leading to equivalent overall hospital cost.

Minimally invasive valve surgery in high-risk patients

The use of minimally, or less invasive, approaches to cardiac valve surgery has increased over the past decade. Because of its less traumatic nature, early studies in lower risk patients demonstrated the approach to be associated with an enhanced recovery, increased patient satisfaction, and good operative outcomes. With time, despite a steep learning curve, surgeons expanded this approach to perform more complex procedures, and include patients with more co-morbidity. The aim of this publication is to review the current literature involving the use of minimally invasive valve surgery (MIVS) in higher-risk patients.

Hybrid approach of percutaneous coronary intervention followed by minimally invasive mitral valve surgery: a 5-year single-center experience

BACKGROUND

The current study evaluated the safety and feasibility of staged ("hybrid") percutaneous coronary intervention (PCI) followed by isolated minimally invasive mitral valve (MV) surgery [PCI + minimally invasive mitral valve surgery (MIMVS)], for patients with concomitant coronary artery and MV disease.

METHODS

A total of 93 patients who underwent PCI + MIMVS for coronary artery and MV disease between February 2009 and April 2014 were retrospectively analyzed.

RESULTS

There were 54 (58.1%) men and 39 (41.9%) women. The mean age was 73±8 years, and all patients had severe mitral regurgitation. PCI was performed for single-vessel coronary artery disease in 40 (43%) patients, two-vessel in 49 (52.7%), and three-vessel in 4 (4.3%). Within a median of 48 days (IQR, 18-71) after PCI, 78 (83.9%) patients underwent primary valve surgery, and 15 (16.1%) underwent re-operative valve surgery, with 56 (60.2%) having MV replacement, and 37 (39.8%) having MV repair. Sixty-five (69.9%) patients were being treated with dual anti-platelet therapy at the time of surgery. The median number of transfused intra-operative red blood cell units was 1 (IQR, 0-2), and the intensive care unit and hospital lengths of stay were 46 hours (IQR, 27-76) and 8 days (IQR, 5-11), respectively. Post-operatively, there was 1 (1.1%) cerebrovascular accident, 2 (2.2%) patients developed acute kidney injury, and 4 (4.3%) required a re-operation for bleeding. Thirty-day mortality occurred in 4 (4.3%) patients. At a mean follow-up of 15.3±13.2 months, 3 (3.4%) patients required target-vessel revascularization. The survival rate was 89% and 85% at 1 and 3 years, respectively.

CONCLUSIONS

In patients with concomitant coronary artery and MV disease, PCI + MIMVS can be safely performed and is associated with good short-term and follow-up outcomes.

Staged percutaneous coronary intervention followed by minimally invasive mitral valve surgery versus combined coronary artery bypass graft and mitral valve surgery for two-vessel coronary artery disease and moderate to severe ischemic mitral regurgitation

BACKGROUND

The optimal treatment for concomitant two-vessel coronary artery disease (CAD) and moderate to severe ischemic mitral regurgitation (IMR) remains unclear. We compared the results of a staged percutaneous coronary intervention followed by minimally invasive mitral valve surgery (PCI+MIVS) versus combined coronary artery bypass graft and mitral valve surgery (CABG+MVS) in this population.

METHODS

All consecutive patients with two-vessel CAD and moderate to severe IMR, who underwent PCI+MIVS or CABG+MVS at our institution between February 2009 and April 2014, were retrospectively evaluated.

RESULTS

There were nine patients identified who underwent PCI+MIVS, and 15 who underwent CABG+MVS, with a mean age of 71±7, and 70±7 years, respectively (P=0.86). The remaining baseline characteristics were similar between both groups, with the exception of a higher prevalence of pre-operative clopidogrel administration (78% versus 27%, P=0.03) and left anterior descending plus left circumflex CAD (78% versus 27%, P=0.03), in those who underwent PCI+MIVS. The PCI+MIVS approach was associated with decreased mean cardiopulmonary bypass (111±41 versus 167±49 min, P=0.01) and aortic cross-clamp (79±32 versus 129±35 min, P=0.003) times, and less median number of intraoperative packed red blood transfusions {2 [interquartile range (IQR), 0-2] versus 3 units (IQR, 1-4), P=0.05}, when compared with CABG+MVS. The rate of mitral valve repair, postoperative complications, 30-day mortality, and 1-year survival did not differ between the surgical approaches.

CONCLUSIONS

PCI+MIVS for two-vessel CAD and moderate to severe IMR is feasible, and associated with satisfactory outcomes, as compared with CABG+MVS.

Aortic valve replacement in patients with a left ventricular ejection fraction ≤35% performed via a minimally invasive right thoracotomy

BACKGROUND

We evaluated the outcomes of patients with aortic valve pathology in the setting of a left ventricular ejection fraction ≤35% who underwent minimally invasive aortic valve replacement (AVR), with or without concomitant mitral valve (MV) surgery.

METHODS

All minimally invasive AVR in patients with a left ventricular ejection fraction ≤35%, performed via a right thoracotomy for aortic stenosis or regurgitation between January 2009 and March 2013, were retrospectively evaluated. The operative characteristics, perioperative outcomes, and 30-day mortality were analyzed.

RESULTS

There were 75 patients identified: 51 who underwent isolated AVR, and 24 who had combined AVR plus MV surgery for moderate to severe mitral regurgitation. In patients undergoing MV surgery, there were 22 (91.7%) MV repairs [ring annuloplasty =7 (37.5%), transaortic edge-to-edge repair =15 (62.5%)], and 2 (8.3%) replacements. No patient required conversion to sternotomy for inadequate surgical field exposure. The median total mechanical ventilation time and intensive care unit length of stay were 14 (IQR, 8-20) and 42 hours (IQR, 26-93 hours) in the isolated AVR group, and 16.5 hours (IQR, 12-61.5 hours) and 95.5 hours (IQR, 43.5-159 hours) in the AVR plus MV surgery group, respectively. The most common post-operative complication was new-onset atrial fibrillation, which occurred in 15 (29.4%) isolated AVR and 4 (16.7%) AVR plus MV surgery patients. The median hospital length of stay and 30-day mortality was 7 days (IQR, 5-12 days) and 1 (2%) in the isolated AVR group, and 10.5 days (IQR, 5-21 days) and 1 (4.3%) for AVR plus MV surgery.

CONCLUSIONS

In patients with aortic valve pathology in the setting of a left ventricular ejection fraction ≤35%, minimally invasive AVR can be performed, with or without concomitant MV surgery, with a low morbidity and mortality.

Anterior Mitral Leaflet Augmentation for Ischemic Mitral Regurgitation Performed Via a Right Thoracotomy Approach

Ischemic mitral regurgitation (MR) after myocardial infarction is associated with poor long-term survival, and the optimal treatment strategy remains debated. The most common repair technique used is a restrictive annuloplasty. However, up to 15% to 30% of patients experience recurrent MR owing to progressive left ventricular remodeling and geometric distortion of the mitral valve apparatus. Anterior mitral leaflet augmentation using a pericardial patch, in combination with a true-sized mitral annuloplasty, has been proposed as an adjunctive technique to increase the durability of valve repair for ischemic MR. Herein, we describe 2 cases of anterior mitral leaflet augmentation with annuloplasty repair for severe ischemic MR via a minimally invasive right thoracotomy, and review the literature regarding patient selection and clinical outcomes of this technique.

Minimally Invasive Mitral Valve Surgery in Truly High-Risk Patients: Are We Pushing the Boundaries?: An Observational Study

OBJECTIVE

This study aimed to assess in a retrospective series of truly high-risk patients who underwent minimally invasive mitral valve surgery: (1) postoperative and long-term results and (2) logistic EuroSCORE and EuroSCORE II discrimination power.

METHODS

Between 2003 and 2013, we reviewed in our institution patients who underwent minimally invasive mitral valve surgery with or without tricuspid valve repair via right minithoracotomy with logistic EuroSCORE of 20 or higher.

RESULTS

Among a total number of 1604, 88 patients were identified. Median logistic and EuroSCORE II was 27.29 (interquartile range, 15.3) and 12.7% (11.3%), respectively. Mean (SD) age was 71.9 (8.4) years; 42 were female (47.7%); 60 patients (68.1%) underwent previous sternotomy. Mitral valve was replaced in 59 (67%) and repaired in 29 (32.9%) patients; tricuspid valve repair was performed in 23 patients (26.1%). Median cardiopulmonary bypass and cross-clamp times were 157 minutes (interquartile range, 131-187 minutes) and 83 minutes (81-116 minutes), respectively; conversion to sternotomy and reopening for bleeding was necessary in 4 (4.5%) and 3 (3.4%) patients; permanent and transient neurological injuries were reported in 6 (6.8%) and 3 (3.4%) patients; acute kidney injury was reported in 13 patients (14.7%); 15 patients (17%) had pulmonary complications. Ten patients died while in the hospital (11.2%). Survival at 6 years was 78% (95% confidence interval, 69-88).

CONCLUSIONS

In this series of truly high-risk patients, minimally invasive mitral surgery was associated with acceptable early mortality and morbidity as well as long-term outcomes; both logistic and EuroSCORE II showed suboptimal discrimination power.

Percutaneous Coronary Intervention Followed by Minimally Invasive Mitral Valve Surgery in Ischemic Mitral Regurgitation

OBJECTIVE

The optimal treatment strategy in patients with coronary artery disease and ischemic mitral regurgitation (IMR) remains controversial. A staged approach of percutaneous coronary intervention (PCI) followed by minimally invasive valve surgery, rather than combined median sternotomy coronary artery bypass and valve surgery, may be a viable alternative.

METHODS

We retrospectively evaluated 31 consecutive patients with coronary artery disease and severe IMR who underwent a staged procedure at our institution between February 2009 and April 2014.

RESULTS

The mean ± SD age, preoperative left ventricular ejection fraction, and mitral regurgitation grade were 72 ± 7 years, 35% ± 11%, and 3.6 ± 0.6, respectively. The mean ± SD Society of Thoracic Surgeons-predicted mortality score was 5.1% ± 4.2%. Percutaneous coronary intervention was performed for 1- and 2-vessel disease in 22 patients (71%) and 9 patients (29%), respectively, with 23 patients (74%) having drug-eluting stents placed. Minimally invasive valve surgery was performed within a median of 36 days after PCI, with 61% of the patients being on dual antiplatelet therapy. Postoperatively, there was 1 case of acute kidney injury, 1 case of reoperation for bleeding, and no cerebrovascular accidents. The 30-day mortality was 3%. The median total hospital length of stay was 8 days (interquartile range, 7-10). At a mean ± SD follow-up of 2.4 ± 1.6 years, 2 patients required PCI for target-vessel revascularization. Actuarial survival at 1 and 5 years was 84% and 80%, respectively.

CONCLUSIONS

A staged approach in patients with coronary artery disease and IMR can be performed with a low perioperative morbidity and good midterm survival.

Combined Mitral and Tricuspid Valve Surgery Performed via a Right Minithoracotomy Approach

OBJECTIVE

Combined mitral and tricuspid valve surgery is associated with an increased perioperative morbidity and mortality. We evaluated the outcomes of a less invasive right minithoracotomy approach in patients undergoing primary or reoperative double-valve surgery.

METHODS

We retrospectively evaluated 132 consecutive patients with mitral and tricuspid valve disease who underwent double-valve surgery via a right minithoracotomy at our institution between January 2009 and April 2014.

RESULTS

The cohort included 81 female (61%) and 51 male (39%) patients, with a mean ± SD age of 67 ± 13 years. The mean ± SD preoperative left ventricular ejection fraction, mitral regurgitation grade, and creatinine were 53% ± 12%, 3.8 ± 0.6, and 1.26 ± 1.17, respectively. The patients underwent primary (88%) or reoperative (12%) mitral and tricuspid valve surgery, which consisted of 88 mitral repairs (67%), 44 mitral replacements (33%), 131 tricuspid repairs (99%), and 1 tricuspid replacement (1%). Postoperatively, there were 6 cases of acute kidney injury (5%), 6 reoperations for bleeding (5%), 4 cerebrovascular accidents (3%), and 12 cases of atrial fibrillation (9%). The median intensive care unit length of stay and total hospital lengths of stay were 61 hours (interquartile range, 43-112 hours) and 8 days (interquartile range, 6-13 days), respectively. The in-hospital mortality was 4%. Actuarial survival at 1 and 5 years was 93% and 88%, respectively.

CONCLUSIONS

In patients undergoing primary or reoperative mitral and tricuspid valve surgery, a right minithoracotomy approach is associated with a low perioperative morbidity and good midterm survival.

Videoscope-assisted cardiac surgery

Videoscope-assisted cardiac surgery (VACS) offers a minimally invasive platform for most cardiac operations such as coronary and valve procedures. It includes robotic and thoracoscopic approaches and each has strengths and weaknesses. The success depends on appropriate hardware setup, staff training, and troubleshooting efficiency. In our institution, we often use VACS for robotic left-internal-mammary-artery takedown, mitral valve repair, and various intra-cardiac operations such as tricuspid valve repair, combined Maze procedure, atrial septal defect repair, ventricular septal defect repair, etc. Hands-on reminders and updated references are provided for reader's further understanding of the topic.

Cross-sectional survey on minimally invasive mitral valve surgery

BACKGROUND

Minimally invasive mitral valve surgery (MIMVS) has become a standard technique to perform mitral valve surgery in many cardiac centers. However, there remains a question regarding when MIMVS should not be performed due to an increased surgical risk. Consequently, expert surgeons were surveyed regarding their opinions on patient factors, mitral valve pathology and surgical skills in MIMVS.

METHODS

Surgeons experienced in MIMVS were identified through an electronic search of the literature. A link to an online survey platform was sent to all surgeons, as well as two follow-up reminders. Survey responses were then submitted to a central database and analyzed.

RESULTS

The survey was completed by 20 surgeons. Overall results were not uniform with regard to contraindications to performing MIMVS. Some respondents do not consider left atrial enlargement (95% of surgeons), complexity of surgery (75%), age (70%), aortic calcification (70%), EuroSCORE (60%), left ventricular ejection fraction (55%), or obesity (50%) to be contraindication to surgery. Ninety percent of respondents believe more than 20 cases are required to gain familiarity with the procedure, while 85% believe at least one MIMVS case needs to be performed per week to maintain proficiency. Eighty percent recommend establishment of multi-institutional databases and standardized surgical mentoring courses, while 75% believe MIMVS should be incorporated into current training programs for trainees.

CONCLUSIONS

These results suggest that MIMVS has been accepted as a treatment option for patients with mitral valve pathologies according the expert panel. Initial training and continuing practice is recommended to maintain proficiency, as well as further research and formalization of training programs.