Simulating mitral repair: lessons learned.

PURPOSE OF REVIEW: With the growing complexity of cardiac surgical cases, increased focus on patient safety, and minimally invasive techniques, simulation-based training has experienced a renaissance. This review highlights important elements of simulation-based training, focusing specifically on available simulators for mitral valve repair and the uses for simulation. RECENT FINDINGS: Referring to simulators as being high or low fidelity is oversimplified. Fidelity is a multifactorial concept, and for surgical task trainers, structural and functional fidelity should be discussed. For mitral valve repair, there are a spectrum of simulators, including tissue-based models, bench-top models, and hybrid models. All these simulator modalities serve a role in training if they align with predetermined objectives. There have been advancements in mitral valve repair simulation, notably patient-specific 3D printed silicone replicas of disease. SUMMARY: There is evidence to support that simulation improves performance in the simulated environment, but future investigation should look to determine whether simulation improves performance in the clinical setting and ultimately patient outcomes.

Is there a role for biomarkers in asymptomatic severe chronic primary mitral regurgitation?

PURPOSE OF REVIEW: Chronic primary mitral regurgitation (MR) is a common heart valve disease with a rising prevalence with the aging populations worldwide. The timing of surgical intervention in patients who have severe MR but remain asymptomatic is often debated. Herein we synthesize the latest American College of Cardiology/American Heart Association (ACC/AHA) and European Society of Cardiology/ European Association for Cardio-Thoracic Surgery (ESC/EACTS) heart valve guidelines in such patients and illustrate how circulating and/or imaging biomarkers can be used to help refine decision making algorithms. RECENT FINDINGS: The approach to decision making and strength of guideline recommendations in patients with asymptomatic stage C1 (left ventricular ejection fraction [LVEF] > 60% and left ventricular end systolic dimension [LVESD] < 40 mm) and stage C2 disease (LVEF ≤ 60% and/or LVESD ≥ 40 mm) are reviewed. While surgical intervention is clearly indicated in patients with stage C2 disease, a multifaceted approach that integrates repairability, expertise, sub-clinical evidence of left ventricular (LV) dysfunction, and patient preferences is required to identify the optimal approach to surveillance vs. surgery. The role of imaging (3D echocardiography, contrast echocardiography, left ventricular global longitudinal strain, and cardiovascular magnetic resonance imaging [CMR]) and circulating (natriuretic peptides) biomarkers in decision making is also reviewed. SUMMARY: The decision making around timing of intervention in chronic primary MR requires a personalized approach that is based on accurate assessments of severity of MR, LV dimensions, LV function, valve morphology/repairability, surgeon and center expertise, and patient wishes. Biomarkers hold promise in refining decision making.

Speckle tracking echocardiography in primary mitral regurgitation: should we reconsider the time for intervention?

Thanks to the improvement in mitral regurgitation (MR) diagnostic and therapeutic management, with the introduction of minimally invasive techniques which have considerably reduced the individual surgical risk, the optimization of the timing for MR "open" or percutaneous surgical treatment has become a main concern which has highly raised scientific interest. In fact, the current indications for intervention in MR, especially in asymptomatic patients, rely on echocardiographic criteria with high severity cut-offs that are fulfilled only when not only mitral valve apparatus but also the cardiac chambers' structure and function are severely impaired, which results in poor benefits for post-operative clinical outcome. This led to the need of new indices to redefine the optimal surgical timing in these patients. Speckle tracking echocardiography provides early markers of cardiac dysfunction due to subtle myocardial impairment; therefore, it could offer pivotal information in this setting. In fact, left ventricular and left atrial strains have already shown evidence about their usefulness in recognizing MR impact not only on symptoms and quality of life but also on cardiovascular events and new-onset atrial fibrillation in these patients. Moreover, right ventricular strain could be used to identify those patients with advanced cardiac damage and different grades of right ventricular dysfunction, which entails higher risks for cardiac surgery that could overweigh surgical benefits. This review aims to describe the importance of reconsidering the timing of intervention in MR and to analyze the potential additive value of speckle tracking echocardiography in this clinical setting.

Routine left atrial appendage occlusion in patients undergoing cardiac surgery: a narrative review.

PURPOSE OF REVIEW: New evidence suggests a greater prevalence of protracted postoperative atrial fibrillation (POAF) than previously recognized. The left atrial appendage (LAA) is the most common source of embolism in patients with nonvalvular atrial fibrillation. In this review, we ask whether there is evidence to support routine LAA occlusion (LAAO) in patients without preexisting atrial fibrillation undergoing cardiac surgery. RECENT FINDINGS: Overall, available studies are small, inconsistent and have varying proportions of patients with and without preexisting atrial fibrillation. There is considerable discrepancy with respect to the efficacy of LAAO in reducing the risk of POAF-related stroke. Only one study reported a lower rate of stroke in the LAAO group compared with no LAAO. Two studies included a subgroup analysis of patients that developed POAF and report a significantly higher rate of stroke in patients that developed POAF and did not undergo LAAO. There are three clinical trials ongoing that are investigating prophylactic LAAO in patients undergoing cardiac surgery: ATLAS, LAA-CLOSURE and LAACS-2. SUMMARY: There is currently insufficient evidence to recommend routine addition of LAAO to lower the risk of postoperative stroke. Ongoing clinical trials will provide important insight into the role of routine LAAO in all patients undergoing cardiac surgery.

The impact of transcatheter edge-to-edge repair on mitral valve annular geometry.

PURPOSE OF REVIEW: Mitral valve transcatheter edge-to-edge repair (TEER) is becoming increasingly common to treat severe mitral regurgitation. However, the lack of concomitant annuloplasty raises concerns regarding its durability. As a result, there is an emerging body of literature evaluating the impacts of TEER on mitral annular geometry. In this review, we summarize the most recent literature evaluating the impacts of TEER on annular geometry in the acute, intermediate and long-term. We also review the relationship between changes in annular geometry and clinical endpoints. RECENT FINDINGS: Current evidence suggests that TEER acutely induces favourable changes in mitral annular size and shape, which may persist for at least up to 1 year. Few studies suggest that TEER-induced annular remodelling is associated with positive clinical outcomes. SUMMARY: The current body of literature is sparse and limited to primarily small case series. Data from the surgical literature suggest that ringless edge-to-edge repair is associated with eventual failure. Unfortunately, few studies evaluate TEER-induced annular changes beyond the acute postprocedural phase. Future research needs to focus on and evaluate the significance of TEER-induced changes in annular dimensions in the long-term.

The anatomy of enjoyment: the flow experience and cardiac surgery.

PURPOSE OF REVIEW: In a time of record levels of physician burnout coupled with a global pandemic, protecting physician wellness is critical. The experience of cognitive flow has been found to enhance both wellness and performance. Although flow has been vastly explored in other fields including elite sport, it has not been deeply investigated or applied in cardiac surgery. Here we discuss flow and flow-promoting techniques employed in other fields that may be beneficial within cardiac surgery. RECENT FINDINGS: Flow is a prevalent experience among surgeons, amplified during operations. Possible strategies to cultivate flow may be separated into individual skills training, such as mindfulness practice and stress management, institutional changes, such as ensuring adequate resources and protected spaces, and strategies targeting the intersectionality of individuals and systems, such as how workplace culture shapes an individual's experience. These techniques may be applicable within cardiac surgery, especially in training. SUMMARY: Flow has been identified as a key component of a happy and meaningful life, and a potential protector against burnout. Harnessing the benefits of flow may help promote flourishing, particularly in demanding fields, such as cardiac surgery.

Right Ventricular Function After Minimally Invasive Mitral Valve Surgery.

OBJECTIVES: Right ventricular (RV) dysfunction is a significant cause of morbidity and mortality after cardiac surgery. Minimally invasive mitral valve surgery (MIMVS) increasingly is being performed. The authors aim was to evaluate postoperative RV function in patients who underwent MIMVS versus traditional mitral valve surgery. DESIGN: Six hundred seventy-five patients who underwent elective isolated mitral valve surgery at Centro Cardiologico Monzino from January 2016 to December 2019 were analyzed. After 1:1 propensity score matching, 60 patients were identified in the MIMVS (study group A) and 58 patients in the median sternotomy (control group B) and compared. SETTING: A university-affiliated scientific institute, monocentric. PARTICIPANTS: Patients. INTERVENTIONS: Mitral valve surgery. MEASUREMENTS AND MAIN RESULTS: No in-hospital deaths occurred. Aortic cross-clamp time (102 [87.5-119] v 83 [61-109] minutes, p = 0.0001), cardiopulmonary bypass duration (161.5 [142.5-181] v 105.5 [74-134] minutes, p < 0.0001) and intensive care unit stay (47 [44-72] v 45 [40-47] hours, p = 0.0015) were significantly longer in group A. The tricuspid annular plane systolic excursion was not different between group A and group B neither postoperatively (15 ± 3 v 14 ± 4 mm, p = 0.1) nor at three-month follow-up (18 ± 4 v 15 ± 3 mm, p = 0.3). No differences in peak postoperative lactates, inotropic score, central venous pressure, and pulmonary artery pulsatility index were observed. The length of hospital stay was significantly shorter in the minimally invasive group (ten [eight-13] v 12 [ten-17], p = 0.006). CONCLUSION: The authors study showed that the surgical strategy had no significant impact on postoperative RV function after mitral valve surgery.

The "P-stitch": A simplified strategy to achieve valvular symmetry during Ozaki procedure.

During Ozaki procedure, relocating a valvular commissure could be technically demanding. This novel technique provides an easy tool to achieve valvular symmetry avoiding commissure shifting.

Storage solutions to improve grafts preservation and longevity in coronary artery bypass grafting surgery: hype or hope?

PURPOSE OF REVIEW: Saphenous vein grafts (SVGs) remain the most-commonly used conduits for coronary artery bypass grafting (CABG).Significant rates of vein graft failure (VGF) remain a limitation of their use as this diminishes the long-term benefits of CABG. The choice of intraoperative SVGs preservation solution is believed to have an impact on graft patency; however, the superiority of one solution over the others remains in question. RECENT FINDINGS: In the present review, we describe the pathophysiological mechanisms underlying the different phases of VGF. We also reviewed the most recent literature comparing and evaluating the efficacy of various storage solutions. These include heparinized saline, autologous heparinized blood, buffered solutions, and crystalloid cardioplegia. SUMMARY: It is clear that the composition of the SVGs storage solution has an impact on vessel wall structure and function. There is a lack of translational and clinical research on the topic; thus, conclusions cannot be drawn regarding the superiority of one solution over the others in terms of VGF. Future research needs to be conducted to address this gap in the literature in order to make meaningful evidence-based recommendations on intraoperative graft storage.

Surgical repair of ischemic mitral regurgitation: one ring does not fit all.

PURPOSE OF REVIEW: The review summarizes the key parameters that can aid in determining the optimal treatment of ischemic mitral regurgitation (IMR). RECENT FINDINGS: Left ventricular (LV) and mitral valve (MV) parameters are important for surgical planning and risk stratification in IMR. Although LV dimensions is one of the main parameters used in the guidelines, volumes more accurately depict LV remodelling. Furthermore, wall motion abnormalities and wall motion score index can also be useful for surgical planning in treatment of IMR. Viability is best measured with cardiac magnetic resonance, but it is not feasible in certain centres. In contrast, measurement of strain with echocardiography is an emerging and feasible tool for estimating viability. MV leaflet tethering and pattern measured with echocardiography are also useful for MV surgery. Anterior leaflet excursion angle can identify patients in whom undersized ring annuloplasty is potentially unsuitable. SUMMARY: Treatment of IMR relies on accurate parameters that can determine the optimal surgical approach. In some patients, lack of viable myocardium suggests inadequacy of revascularization and thus, an adjunctive left ventricular reconstruction may be necessary. Degree and pattern of MV leaflet tethering can indicate whether ring annuloplasty, which is the most common repair technique, is sufficient or an adjunctive sub-valvular intervention is beneficial.

Zone 0 frozen elephant trunk for type A retrograde acute aortic dissection following endovascular stenting of the arch.

A 70-year-old man underwent the frozen elephant trunk (FET) procedure with zone 0 debranching following a failed endovascular repair for type B aortic dissection and a stent-graft deployment in zone 1 for a retrograde type A aortic dissection. Zone 0 deployment is a novel approach that is valuable as a bailout strategy in urgent cases and it can potentially improve the technical feasibility of the FET while minimizing its ischemic complications.

Ticagrelor use and practice patterns among Canadian cardiac surgeons.

BACKGROUND AND AIM: The P2Y12 platelet receptor inhibitor ticagrelor is widely used in patients following acute coronary syndromes or in those who have received coronary stents. Bentracimab is a monoclonal antibody-based reversal agent that is being formally evaluated in a Phase 3 clinical trial. Here, we probe the knowledge, attitudes, and practice patterns of cardiac surgeons regarding their perioperative management of ticagrelor and potential application of a ticagrelor reversal agent. METHODS: A questionnaire was developed by a working group of cardiac surgeons to inquire into participants' practices and beliefs regarding ticagrelor and disseminated to practicing, Canadian-trained cardiac surgeons. RESULTS: A total of 70 Canadian-trained cardiac surgeons participated. Bleeding risk was identified as the most significant consideration when surgically revascularizing ticagrelor-treated patients (90%). There is variability in the duration of withholding ticagrelor before coronary artery bypass graft procedure in a stable patient; 44.3% wait 3 days and 32.9% wait 4 days or longer. Currently, 15.7% of cardiac surgeons prophylactically give platelet transfusions and fresh frozen plasma intraoperatively following protamine infusion in patients who have recently received ticagrelor. Interestingly, 47.1% of surveyed surgeons were aware of a reversal agent for ticagrelor, 91.4% of cardiac surgeons would consider utilizing a ticagrelor reversal agent if available, and 51.4% acknowledged that the introduction of such an agent would be a major advance in clinical practice. CONCLUSIONS: The present survey identified ticagrelor-related bleeding as a major concern for cardiac surgeons. Surgeons recognized the significant unmet need that a ticagrelor reversal agent would address.

Cardiac surgeons' concerns, perceptions, and responses during the COVID-19 pandemic.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has had an unprecedented impact on health care and cardiac surgery. We report cardiac surgeons' concerns, perceptions, and responses during the COVID-19 pandemic. METHODS: A detailed survey was sent to recruit participating adult cardiac surgery centers in North America. Data regarding cardiac surgeons' perceptions and changes in practice were analyzed. RESULTS: Our study comprises 67 institutions with diverse geographic distribution across North America. Nurses were most likely to be redeployed (88%), followed by advanced care practitioners (69%), trainees (28%), and surgeons (25%). Examining surgeon concerns in regard to COVID-19, they were most worried with exposing their family to COVID-19 (81%), followed by contracting COVID-19 (68%), running out of personal protective equipment (PPE) (28%), and hospital resources (28%). In terms of PPE conservation strategies among users of N95 respirators, nearly half were recycling via decontamination with ultraviolet light (49%), followed by sterilization with heat (13%) and at home or with other modalities (13%). Reuse of N95 respirators for 1 day (22%), 1 week (21%) or 1 month (6%) was reported. There were differences in adoption of methods to conserve N95 respirators based on institutional pandemic phase and COVID-19 burden, with higher COVID-19 burden institutions more likely to resort to PPE conservation strategies. CONCLUSIONS: The present study demonstrates the impact of COVID-19 on North American cardiac surgeons. Our study should stimulate further discussions to identify optimal solutions to improve workforce preparedness for subsequent surges, as well as facilitate the navigation of future healthcare crises.

The use of ultrasound to assess aortic biomechanics: Implications for aneurysm and dissection.

Arterial stiffening, which occurs when conduit arteries thicken and lose elasticity, has been associated with cardiovascular disease and increased risk for future cardiovascular events. Specifically, aortic stiffening plays a large role in the pathogenesis of vascular diseases, such as aneurysm formation and dissection. Current parameters used to assess risk of aortic rupture include absolute diameter and growth rate. However, these properties lack the reliability required to accurately risk-stratify patients. As with any elastic conduit, it is important to assess the biomechanical properties of the aorta in order to assess cardiovascular risk and prevent disease progression. There are several invasive and noninvasive methods by which stiffness of the large arteries can be assessed. Of particular interest are ultrasound-based methods, such as tissue Doppler imaging and speckle-tracking echocardiography, due to their noninvasive and feasible nature. In this review, we summarize studies demonstrating utility of noninvasive ultrasound imaging methods for measuring aortic biomechanics for the assessment and management of aortic aneurysms.

Quantified pre-operative neurological dysfunction predicts outcome after coronary artery bypass surgery.

AIMS: Patients undergoing coronary artery bypass grafting (CABG) surgery may experience neurological impairment. We examined whether intraoperative regional cerebral oxygen saturation (rSO2) and neurological dysfunction prior to surgery, measured by robotic technology, are important predictors of post-operative performance following CABG surgery. METHODS: Adult patients undergoing CABG surgery were recruited for this single-center prospective observational study. Intraoperative rSO2 was captured using the FORESIGHT cerebral oximeter. Neurological assessment was performed pre-operatively and 3 months following surgery using robotic technology and a standardized pen-and-paper assessment. Linear regression models were generated to determine the predictive ability of both intraoperative rSO2 and pre-operative performance on post-operative neurological outcome. RESULTS: Forty patients had complete data available for analysis. Quantified pre-operative performance accounted for a significantly larger amount of variance in post-operative outcome compared to intraoperative rSO2. In particular, pre-operative scoring on a cognitive visuospatial task accounted for 82.2% of variance in post-operative performance (b = 0.937, t(37) = 12.98, p = 1.28e-5). DISCUSSION: Our results suggest that pre-operative performance is a stronger indicator of post-operative neurological outcome than intraoperative rSO2, and should be included as an important variable when elucidating the relationship between cerebral oxygen levels and post-operative neurological impairment. Rigorous neurological assessment prior to surgery can provide valuable information about each individual patient's path to recovery. CONCLUSION: Using robotic technology, quantified neurological impairment prior to CABG surgery may better predict post-operative neurological outcomes, compared to intraoperative rSO2 values.

Left atrium perforation with lung injury after catheter ablation.

Left atrial perforation is a known complication following pulmonary vein catheter ablation. Our case of a 62-year-old female underwent urgent surgery for repair of left atrium perforation with left pleural effusion as a late complication after multiple transcatheter radiofrequency pulmonary vein ablations for persistent atrial fibrillation.

Learning curve predictors for minimally invasive mitral valve surgery; how far should the rabbit hole go?

OBJECTIVE: To analyze predictors that influence the learning curve of minimally invasive mitral valve surgery (MIMVS). METHODS: Patients who underwent MIMVS between March 2010 to March 2015 were retrospectively analyzed. Predictive factors that influence the learning curve were analyzed. RESULTS: One hundred and five patients were included in the analysis. Cardiopulmonary bypass (CPB) time in minutes was 158.72 ± 40.98 and the aortic cross-clamp (ACC) time in minutes was 114.48 ± 27.29. There were three operative mortalities, one stroke and five >2+ mitral regurgitation. ACC time in minutes was higher in the low logistic Euroscore II (LES) group (LES < 5% = 118.42 ± 27.94) versus (LES ≥ 5 = 88.66 ± 22.26), P < .05 while creatinine clearance in µmol/L was higher in the LES < 5% group (LES < 5% = 84.32 ± 33.7) versus (LES ≥ 5% = 41.66 ± 17.14), (P < .05). One patient from each group required chest tube insertion for pleural effusion P < .05. The cumulative sum analysis (CUSUM) for the first 25 patients had CPB and ACC times that reached the upper limits. Between 25 to 64 patients the curve remained stable while with the introduction of reoperations and complex surgical procedures the CUSUM reached the upper limits. CONCLUSIONS: The learning curve is affected by many factors but this should not desist surgeons from approaching this technique. The introduction of high-risk patients in clinical practice should be carefully measured based on surgeon experience.

Hybrid Minimally Invasive Approach for Transvenous Lead Extraction: A Feasible Technique in High-Risk Patients.

INTRODUCTION: Despite the overall safety, transvenous lead extraction (TLE) remains a challenging procedure with inherent risks, where surgery can still be required in elective cases. In this study, we report our experience with a minimally invasive "hybrid" approach, defined as a procedure performed by an electrophysiologist with the support of a cardiac surgeon in the same operative session. METHODS AND RESULTS: We reported 12 cases of planned hybrid lead extraction; minithoracotomy and thoracoscopy were performed on 10 (83%) and 2 (17%) patients, respectively. A total of 25 leads out of 27 (median lead age 19 years) were successfully extracted with laser, mechanical or combined transvenous sheath. In 3 patients, the direct monitoring of vascular and myocardial integrity allowed for prompt treatment of potential vascular injury during the lead extraction maneuvers. Mean in-hospital stay was 4 ± 2 days. There were no major intraoperative complications and no deaths occurred after 30 days' follow-up. CONCLUSION: The hybrid approach, with minithoracotomy or thoracoscopy, is feasible and it might increase the safety in the most challenging TLE procedures: the minimally invasive surgical intervention allows for continuous monitoring of the critical cardiac structures and prompt treatment of potential complications.

Hybrid ablation for atrial fibrillation: current approaches and future directions.

PURPOSE OF REVIEW: Catheter ablation of atrial fibrillation has rapidly evolved during the past decade: although the treatment of paroxysmal atrial fibrillation via a transcatheter approach has been consistently successful, persistent and long-standing atrial fibrillation still represents a major clinical challenge with less favorable outcomes to date. Because novel, minimally invasive surgical approaches have been developed for atrial fibrillation ablation, the aim of the present review is to analyze the current evidence surrounding the integration of surgical and transcatheter strategies in a hybrid fashion for the treatment of atrial fibrillation. RECENT FINDINGS: Long-standing persistent, atrial fibrillation requires further understanding. Wide antral circumferential ablation of the pulmonary veins represents the cornerstone of any ablation therapy. Additional linear lesions and/or targeting complex fractionated atrial electrograms may also be considered. One of the limitations is achieving a transmural lesion. The combined endocardial and epicardial approach may represent a superior approach. SUMMARY: Hybrid ablation of atrial fibrillation represents a novel therapeutic strategy for the treatment of complex scenarios, such as long-standing persistent atrial fibrillation. A specialized team including dedicated surgeons and cardiologists appears to be crucial in order to achieve durable and satisfactory outcomes following hybrid ablation of atrial fibrillation.

Total arterial grafting is associated with improved clinical outcomes compared to conventional myocardial revascularization at 10 years follow-up.

The use of arterial conduits is associated with incremental benefits when compared to conventional CABG surgery, albeit there is a paucity of data regarding the long-term outcomes of either techniques. Among 973 consecutive patients undergoing CABG, a propensity-match study was performed to compare total arterial revascularization technique (G1) with a conventional approach (LITA on LAD plus additional SVGs, G2). The study population was propensity-matched based on preoperative characteristics (age, sex, risk factors). Mean number of grafted vessels (G1 = 2.39 ± 0.55 vs G2 = 2.37 ± 0.7; p = 0.79) and aortic cross-clamp time (G1 = 36 ± 6 vs G2 = 35 ± 6 min; p = 0.31) were similar while CPB time was significantly longer in Group 2 (G1 = 50 ± 7 vs G2 = 70 ± 8 min; p = 0.03). Hospital mortality (G1 = 0.6 % vs G2 = 1.3 %; p = 0.41) and overall incidence of postoperative complications were also comparable. Cox regression analysis depicted conventional CABG as an independent predictor for MACCEs (HR = 4.53, CI 95 % = 2-10.28; p < 0.001). Median follow-up time was 112 months: actuarial survival free from cardiac death (G1 = 100 % vs G2 = 95 ± 2.1 %; p = 0.046) and MACCEs (G1 = 97.3 ± 1.5 % vs G2 = 79.4 ± 3.8 %; p < 0.001) was significantly improved in patients undergoing total arterial grafting. Total arterial myocardial revascularization is associated with significantly improved outcomes at 10 years follow-up in terms of cardiac-related mortality and overall event-free survival.