Comparison of Endoaortic and Transthoracic Aortic Clamping in Less-Invasive Mitral Valve Surgery

Single-Center Prospective Study of Cross-Clamp vs Balloon Occlusion in Robotic Mitral Surgery

BACKGROUND

Transthoracic aortic cross-clamp and endoaortic balloon occlusion have both been shown to have comparable safety profiles for aortic occlusion. Because most surgeons use only one technique, we sought to compare the outcomes when a homogeneous group of surgeons changed their occlusion technique from aortic cross-clamp to balloon occlusion.

METHODS

We changed our technique from aortic cross-clamp to balloon occlusion in November 2022. This allowed us to conduct a prospective treatment comparison study in the same group of surgeons. Propensity score matching was used to match cases (balloon occlusion) 1:3 to controls (aortic cross-clamp) based on age, sex, body mass index, concomitant maze procedure, and tricuspid valve repair.

RESULTS

Total of 411 patients underwent robotic mitral surgery from 2020 through 2023. Propensity score matching was used to match 56 balloon occlusion patients to 168 aortic cross-clamp patients. The 224 patients were a median age of 65 years (interquartile range, 55.6-70.0 years), and 119 (53%) were men. All valves were successfully repaired. Balloon occlusion had a shorter median cardiopulmonary bypass (CPB) time compared with aortic cross-clamp (84.0 vs 94.5 minutes, P = .006). Median cross-clamp time (64.0 vs 64.0 minutes, P = .483) and total surgery time (5.9 vs 6.1 hours, P = .495) did not differ between groups. There were no in-hospital deaths. There were 5 surgeons who performed various combinations of console and bedside roles. CPB, cross-clamp, and surgery durations were not significantly affected by the different surgeon combinations.

CONCLUSIONS

Compared with aortic cross-clamp, balloon occlusion has similar perioperative and early postoperative outcomes. Additionally, it likely introduces a 10-minute reduction in total CPB time.

Endoaortic balloon occlusion versus transthoracic cross-clamp for totally endoscopic robotic mitral valve surgery: a retrospective cohort study

Endoaortic balloon occlusion (EABO) and transthoracic cross-clamping have been shown to have comparable safety profiles for aortic occlusion in minimally invasive mitral valve surgery (MIMVS). However, few studies have focused exclusively on the totally endoscopic robotic approach. We sought to compare outcomes for patients undergoing totally endoscopic robotic mitral valve surgery with aortic occlusion via EABO and transthoracic clamping after a period where EABO was unavailable required us to use the transthoracic clamp. Retrospective review identified 113 patients who underwent robotic mitral valve surgery at our facility between 2019 and 2021 with EABO (n = 71) or transthoracic clamping (n = 42). Relevant data were extracted and compared. Preoperative characteristics were similar other than a higher rate of coronary artery disease [EABO: 69.0% (49/71) vs clamp: 45.2% (19/42), p = .02] and chronic lung disease [EABO: 38.0% (27/71) vs clamp: 9.5% (4/42), p < .01] in the EABO group. Median percutaneous cardiopulmonary bypass time, operative time, and cross-clamp time were comparable. Similar rates of postoperative bleeding complications were observed, and no aortic complications were observed. One patient in each group underwent conversion to an open approach. 30-day mortality and readmission rates were comparable. EABO and transthoracic clamp were associated with similar bleeding and aortic outcomes, and mortality and readmission rates were comparable at thirty days postoperatively. Our findings support the comparable safety of the two techniques, which is well documented in studies encompassing all MIMVS techniques, within the specific context of the totally endoscopic robotic approach.

Cost and Clinical Outcomes Evaluation Between the Endoaortic Balloon and External Aortic Clamp in Cardiac Surgery

OBJECTIVE

Endoaortic balloon occlusion facilitates cardioplegic arrest during minimally invasive surgery (MIS). Studies have shown endoclamping to be as safe as traditional aortic clamping. We compared outcomes and hospital costs of endoclamping versus external aortic occlusion in a large administrative database.

METHODS

There were 52,882 adults undergoing eligible cardiac surgery (October 2015 to March 2020) identified in the Premier Healthcare Database. Endoclamp procedures (n = 419) were 1:3 propensity score matched to similar procedures using external aortic occlusion (n = 1,244). Generalized linear modeling measured differences in in-hospital complications (major adverse renal and cardiac events, including mortality, new-onset atrial fibrillation, acute kidney injury [AKI], myocardial infarction [MI], postcardiotomy syndrome, stroke/transient ischemic attack [TIA], and aortic dissection) and length of stay (LOS).

RESULTS

The mean age was 63 years, and 53% were male (n = 882). The majority (93%, n = 1,543) were mitral valve procedures, and 17% of procedures (n = 285) were robot-assisted. Total hospitalization costs were not statistically significantly different between the 2 groups ($52,158 vs $49,839, P = 0.06). The median LOS was significantly shorter in the endoclamp group (incident rate ratio = 0.87, P < 0.001). Mortality, atrial fibrillation, AKI, and stroke/TIA were similar between the 2 groups. MI and postcardiotomy syndrome were lower in the endoclamp group (odds ratio [OR] = 0.14, P = 0.006, and OR = 0.27, P = 0.005). There were no aortic dissections in the endoclamp group.

CONCLUSIONS

Aortic endoclamping in MIS was associated with similar costs, shorter LOS, no dissections, and comparably low mortality and stroke rates when compared with external clamping in this hospital billing dataset. These results demonstrate the clinical safety and efficacy of endoaortic balloon clamping in a real-world setting. Further studies are warranted.

A Retrospective Evaluation of Endo-Aortic Balloon Occlusion Compared to External Clamping in Minimally Invasive Mitral Valve Surgery

We compare outcomes of endo-aortic balloon occlusion (EABO) vs external aortic clamping (EAC) in patients undergoing minimally invasive mitral valve surgery (MIMVS) in the Society of Thoracic Surgeons (STS) Adult Cardiac Surgery Database. Adults undergoing mitral valve surgery (July 2017-December 2018) were identified within the STS database (N = 60,607). Total 7,978 patients underwent a minimally invasive approach (including robotically assisted). About 1,163 EABO patients were 1:1 propensity-matched to EAC patients using exact matching on age, sex, and type of mitral procedure, and propensity score average matching for 16 other risk indicators. Early outcomes were compared. Categorical variables were compared using logistic regression; hospital and intensive care unit length of stay were compared using negative binomial regression. In the matched cohort, mean age was 62 years; 35.9% were female, and 86% underwent mitral valve repair. Cardiopulmonary bypass time was shorter for EABO vs EAC group (125.0 ± 53.0 vs 134.0 ± 67.0 minutes, P = 0.0009). There was one aortic dissection in the EAC group and none in the EABO group (P value > 0.31), and no statistically significant differences in cross-clamp time, major intraoperative bleeding, perioperative mortality, stroke, new onset of atrial fibrillation, postoperative acute kidney injury, success of repair. Median hospital LOS was shorter for EABO vs EAC procedures (4 vs 5 days, P < 0.0001). In this large, retrospective, STS database propensity-matched analysis ofpatients undergoing MIMVS, we observed similar safety outcomes for EABO and EAC, including no aortic dissections in the EABO group. The EABO group showed slightly shorter CPB times and hospital LOS.

Comparative myocardial protection of endoaortic balloon versus external clamp in minimally invasive mitral valve surgery

AIMS

Minimally invasive mitral valve surgery leads to shorter postoperative recovery time, cosmetic advantages and significant pain reduction compared with the standard sternotomy approach. Both an external aortic clamp and an endoaortic balloon occlusion can be used to manage the ascending aorta and the myocardial protection. In this study, we aimed to compare these two strategies in terms of effectiveness of myocardial protection and associated early postoperative outcomes.

METHODS

We investigated the retrospective records of prospectively collected data of patients treated by minimally invasive mitral valve surgery from March 2014 to June 2019. A total of 180 cases (78 in the external aortic clamp group and 102 in the endoaortic balloon clamp group) were collected. A propensity weighting analysis was adopted to adjust for baseline variables.

RESULTS

The endoaortic balloon clamp presented higher EuroSCORE II (higher reoperative surgery rate). The intra- and postoperative data were similar between the two groups: the postoperative troponin-I levels, peak of serum lactates and rate of myocardial infarction were also comparable. The endoaortic clamp group recorded longer operative, cardiopulmonary bypass and cross-clamp times. The external clamp group showed a higher rate of postoperative atrial fibrillation and conduction block.

CONCLUSIONS

In experienced centers, the use of the endoaortic balloon clamp is safe, reproducible and comparable to the external aortic clamp regarding the effectiveness of myocardial protection: its employment might facilitate minimally invasive mitral valve surgery.

Magnetic Resonance Imaging for Cerebral Micro-embolizations During Minimally Invasive Mitral Valve Surgery

The role of aortic clamping techniques on the occurrence of neurological complications after right mini-thoracotomy mitral valve surgery is still debated. Brain injuries can occur also as silent cerebral micro-embolizations (SCM), which have been linked to significant deficits in physical and cognitive functions. Aims of this study are to evaluate the overall rate of SCM and to compare endoaortic clamp (EAC) with trans-thoracic clamp (TTC). Patients enrolled underwent a pre-operative, a post-operative, and a follow-up MRI. Forty-three patients were enrolled; EAC was adopted in 21 patients, TTC in 22 patients. Post-operative SCM were reported in 12 cases (27.9%). No differences between the 2 groups were highlighted (23.8% SCM in the EAC group versus 31.8% in the TTC). MRI analysis showed post-operative SCM in nearly 30% of selected patients after right mini-thoracotomy mitral valve surgery. Subgroup analysis on different types of aortic clamping showed comparable results. CLINICAL RELEVANCE: The rate of SCM reported in the present study on patients undergoing minimally invasive MVS and RAP is consistent with data in the literature on patients undergoing cardiac surgery through median sternotomy and antegrade arterial perfusion. Moreover, no differences were reported between EAC and TTC: both the aortic clamping techniques are safe, and the choice of the surgical setting to adopt can be really done according to the patient's characteristics.

Endo-Aortic vs. Trans-Thoracic Clamping in Right Mini-Thoracotomy Mitral Valve Surgery: Outcome on Myocardial Protection

Background: Perfusion strategies and aortic clamping techniques for right mini-thoracotomy mitral valve (MV) surgery have evolved over time and remarkable short- and long-term results have been reported. However, some concerns have raised about the adequacy of myocardial protection during the minimally invasive approach, particularly with the endo-aortic clamp (EAC). Aim of this study was to compare the efficacy, in terms of myocardial preservation, of the EAC with the trans-thoracic aortic clamp (TTC) in patients undergoing right mini-thoracotomy MV surgery. Methods: A single center, prospective observational study was performed on patients undergoing right mini-thoracotomy MV surgery with retrograde arterial perfusion and EAC or TTC. A propensity matched analysis was performed to compare the two groups. Primary outcome was the comparison between cardiac troponin T levels measured at different time-points after surgery. Results: Eighty EAC patients were compared with 37 TTC patients. No cases of myocardial infarction or low cardiac-output syndrome were overall reported. No differences were recorded in terms of stroke, peri-operative mortality, and in the release of myocardial markers, lactates levels and need for inotropic support at different time-points after surgery. CK-MB peak levels were significantly lower in the EAC group. Conclusion: Despite concerns arising about the EAC, this prospective study shows equivalence in terms of myocardial preservation of the EAC compared with the TTC in patients undergoing right mini-thoracotomy MV surgery.

Minimally Invasive and Robotic Mitral Valve Surgery: Methods and Outcomes in a 20-Year Review

In the mid- to late-1990s the cardiac surgery community began to apply limited incisions in mitral valve surgery. Ministernotomies and right-sided minithoracotomies were placed instead of the classic midline sternotomy. Adjunct technology such as videoscopy, advanced peripheral cannulation techniques, procedure specific long shafted surgical instruments, as well as surgical robots became available, and the procedures were refined in a stepwise fashion. In 2021, minimally invasive mitral valve repair is routine at many centers around the globe. We reviewed a total of 50 consecutive patient series published on the topic between 1999 and 2019. Three main versions of minimally invasive mitral valve surgery were applied in 20,539 patients. The surgical methods, their specific results, and the cumulative outcome of less invasive mitral valve surgery published over more than 20 years are reported and an integrated view on what less invasive mitral valve surgery can offer is presented.

Mitral valve surgery: current status and future prospects of the minimally invasive approach

Introduction: During the past five years the approach to procedural planning, operative techniques and perfusion strategies for minimally invasive mitral valve surgery (MIMVS) has evolved. With the goal to provide a maximum of patient safety the procedure has been modified according to individual patient characteristics and is largely based on preoperative imaging.Areas covered: In this review article we describe the important factors in image based therapy planning and simulation, different access strategies, the operative key-steps, a rationale use of devices, and highlight a few future developments in the field of MIMVS. Published studies were identified through pearl growing, citation chasing, a search of PubMed using the systematic review methods filter, and the authors' topic knowledge.Expert opinion: With the help of expert teams including surgeons specialized in mitral repair, anesthesiologists and perfusionists a broad spectrum of mitral valve pathologies and related pathologies can be treated with excellent functional outcomes. Avoiding procedure related complications is the key for success for any MIMVS program.

Steps Forward in Minimally Invasive Cardiac Surgery: 10-Year Experience

BACKGROUND

Minimally invasive cardiac surgery (MICS) has constantly evolved over the past years, and new technologies have been introduced. The aims of this study were to analyze the evolution of our 10-year experience in MICS and to highlight outcomes in different spans of time.

METHODS

Patients undergoing MICS for mitral valve, tricuspid valve, and/or atrial septal defect or atrial masses from November 2005 to November 2015 were retrospectively analyzed. A comparative analysis was performed by identifying 2 groups: the control group (in the first time span of our experience) and the tailored group (patients who underwent surgery after a full preoperative anatomic evaluation with allocation to the proper setting).

RESULTS

During the study period 971 patients underwent MICS. MICS procedures increased from 44% in 2006 to 96% in 2015. Subgroup analysis revealed a significant decrease in the rate of procedures performed with retrograde arterial perfusion (99.1% vs 91.7%, P < .0001), a significant increase in the rate of complex mitral valve procedures (22.4% vs 7.9%, P < .0001), and a significant decrease in the rate of stroke (from 5.2% to 1%, P < .001) in the tailored group. The logistic regression analysis showed that the tailored approach was a protective factor against neurologic complications.

CONCLUSIONS

The present study shows the considerable and attractive results of our decision-making process based on the tailored approach. The 10-year outcome analysis demonstrated a trend toward a progressive decrease in the overall rate of postoperative complications and a significant protective effect of the tailored approach on the occurrence of stroke.