Simplifying Mitral Valve Repair: A Guide to Neochordae Reconstruction.

Mitral valve reconstruction techniques using polytetrafluoroethylene sutures are associated with high repair rates and excellent durability but are dependent on accurate neochordae length estimates. Current strategies to determine the appropriate length of artificial neochordae commonly rely on nonphysiologic saline testing on the arrested heart, with erroneous lengths resulting in residual mitral regurgitation. We present a guide for reproducible and accurate neochordae reconstruction based upon transesophageal echocardiographic measurements, which simplifies mitral repair for most patients with degenerative mitral regurgitation and can be used in conventional or minimally invasive approaches.

Hybrid Double Valve Replacement for Multivalvular Disease With Severe Mitral Annular Calcification.

Severe mitral annular calcification poses a significant challenge, particularly in higher risk, frail, elderly patients with multivalvular disease. Both surgical and transcatheter options exist but remain fraught with risks of paravalvular leak, atrioventricular groove disruption, patient prosthesis mismatch, and left ventricular outflow tract obstruction. We present an innovative hybrid surgical approach to manage severe aortic and mitral valve disease in a Jehovah's Witness patient with severe circumferential mitral annular calcification.

Minimally Invasive Hybrid Approach to High Risk Mitral Disease With Severe Mitral Annular Calcification.

Severe circumferential mitral annular calcification (MAC) remains a significant challenge, complicating surgical treatment of mitral valve disease. Transcatheter treatment options are attractive; however, they remain fraught with risks of annular fixation, paravalvular leak, atrioventricular-groove disruption, and left-ventricular outflow tract obstruction. We describe a novel minimally invasive hybrid technique of transcatheter mitral valve replacement in a patient with severe circumferential MAC.

Early Clinical Experiences of Robotic Assisted Aortic Valve Replacement for Aortic Valve Stenosis with Sutureless Aortic Valve.

Robotic assisted aortic valve surgery is still challenging and debatable. We retrospectively reviewed our cases of robotic assisted aortic valve replacement utilizing sutureless aortic valve with following surgical technique: 3 ports, 1 for endoscope and 2 for the robotic arms were inserted in the right chest and da Vinci Si robotic system (Intuitive Surgical, Sunnyvale, CA, USA) was adapted to these ports. Cardiopulmonary bypass was initiated through peripheral cannulations. A vent cannula was placed through the right superior pulmonary vein and a cardioplegia cannula in the ascending aorta. After cardioplegic arrest following aortic cross-clamp, the aortic valve was exposed through a clam shell aortotomy. Valvectomy along with decalcification was performed. Next using 3 guiding sutures the Perceval S valve (LivaNova, London, UK) was parachuted down and deployed. After confirming valve position, the aortotomy was closed. There were no major complications during the procedures and no conversion to sternotomy. Exposure of aortic valve was of high quality. Valvectomy required assistance with long scissors by the bedside surgeon for excision of the severely calcified valve cusps and effective decalcification of annulus. Postoperative convalescence was uncomplicated except for postoperative atrial fibrillation in 1 patient. Robotic assistance in aortic valve procedure enabled excellent exposure of the aortic valve and improved manipulation and suturing of the aortic annulus and aorta. There needs to be improvement of instrumentation for valve debridement and removal of calcium from the annulus. In addition, the sutureless valve technology contributes to the feasibility and the efficacy of this procedure.

Whole body perfusion strategy for aortic arch repair under moderate hypothermia.

INTRODUCTION: Aortic arch reconstruction under moderate hypothermia is commonly performed with antegrade cerebral perfusion (ACP) for brain protection; however, hypothermia alone is often solely relied upon for visceral and lower body protection. We investigated whether the addition of simultaneous lower body perfusion to ACP (whole body perfusion - WBP) may ameliorate the metabolic derangements of moderate hypothermic circulatory arrest (MHCA). METHODS: Between 2008 and 2014, 106 consecutive patients underwent elective or emergent aortic arch surgery with MHCA, with either ACP only (44 patients, 66±12 years, 30% female) or WBP (62 patients, 61±15 years, 31% female). Primary outcomes included 30-day/in-hospital mortality, intensive care unit (ICU) and hospital lengths of stay (LOS) and specific parameters of metabolic recovery. RESULTS: There were no significant differences between the groups in 30-day/in-hospital mortality (ACP: 3 (6.8%), WBP: 2 (3.2%); p=0.65), stroke (ACP: 1 (2.3%), WBP: 1 (1.6%); p=1.0) or renal failure (ACP: 2 (4.5%), WBP: 1 (1.5%); p=0.57). In the WBP group, we identified a significant reduction in lactate level at ICU admission (ACP 5.5 vs. WBP 3.5 mmol/L; p=0.002), time to lactate normalization (p=0.014) and median ICU length-of-stay (ACP 3 vs. WBP 1 days; p=0.049). There was no difference in post-operative creatinine (ACP: 104, WBP: 107 µmol/L; p=0.66). After multivariable regression adjustment, perfusion strategy no longer remained an independent predictor of ICU discharge time (p=0.09), however, cardiopulmonary bypass time (p=0.02), age (p=0.012) and emergent surgery (p=0.02) were. CONCLUSIONS: A WBP strategy during aortic arch reconstruction with MHCA may be associated with more rapid normalization of metabolic parameters and reduced ICU length of stay compared to using ACP alone. Further evaluation with a randomized trial is warranted.

Early clinical outcomes of a novel self-expanding transapical transcatheter aortic valve bioprosthesis.

OBJECTIVE: Coronary obstruction remains a challenging complication of transcatheter aortic valve replacement; however, a new self-expanding transapical prosthesis may reduce this risk. The purpose of this study was to evaluate the early 1-year outcomes of patients with low coronary heights who received the Acurate TA bioprosthesis (Symetis, Ecublens, Switzerland). METHODS: Between May 2014 and April 2015, 30 consecutive patients (aged 85 ± 6 years, 63% were female, Society of Thoracic Surgeons score 8.4 ± 6.0) with severe, symptomatic aortic stenosis underwent transcatheter aortic valve replacement with the Acurate TA bioprosthesis. Relevant patient characteristics included reoperation in 47% (n = 14), peripheral vascular disease in 43% (n = 13), and porcelain aorta in 30% (n = 9). The mean left and right coronary heights were 10.8 ± 1.5 mm and 16.4 ± 4.1 mm, respectively, with a sinus of Valsalva : annular ratio of 1.3 ± 0.8. RESULTS: All 30 device implants were successful. The 30-day in-hospital mortality was 3.3% (n = 1), and no patients had coronary obstruction or stroke. One patient (3.3%) had apical rupture requiring cardiopulmonary bypass for repair, 1 patient (3.3%) had a localized femoral artery dissection, and 1 patient (3.7%) required a new pacemaker. There were no other complications. Mean and peak transaortic valve gradients decreased from 59 ± 17 and 84 ± 31 mm Hg to 14 ± 7 and 28 ± 12 mm Hg, respectively (P < .0005). No patients had more than mild paravalvular aortic insufficiency. At 30 days, there were no further complications and 96.7% (n = 29) were in New York Heart Association class I/II. Survival at 30 days and 1 year was 97% and 89%, respectively. CONCLUSIONS: The Symetis Acurate TA device demonstrates high procedural success and excellent acute and 1-year patient outcomes. The device allows safe implantation in patients at higher risk for coronary artery obstruction.

Whole body perfusion for hybrid aortic arch repair: evolution of selective regional perfusion with a modified extracorporeal circuit.

BACKGROUND: Patients undergoing hybrid aortic arch reconstruction require careful protection of vital organs. We believe that whole body perfusion with tailored dual circuitry may help to achieve optimal patient outcomes. METHODS: Our circuit has evolved from a secondary circuit utilizing a cardioplegia delivery device for lower body perfusion to a dual-oxygenator circuit. This allows individually controlled regional perfusion with ease of switching from secondary to primary circuit for total body flow. The re-design allows for separate flow and temperature regulation with two oxygenators in parallel. All patients underwent a single-stage operation for simultaneous treatment of arch and descending aortic pathology via a sternotomy, using a hybrid frozen elephant trunk technique. RESULTS: We report six consecutive patients undergoing hybrid arch and frozen elephant trunk reconstruction using a dual-oxygenator circuit. Five patients underwent elective surgery and one was emergent. One patient had an acute dissection while three underwent concomitant procedures, including a Ross procedure and two valve-sparing root reconstructions. Three cases were redo sternotomies. The mean pump time was 358 ± 131 min, the aortic cross clamp time 243 ± 135 min, the cardioplegia volume of 33,208 ml ± 16,173, cerebral ischemia 0 min, lower body ischemia 76 ± 34 min and the average lower body perfusion time was 142 min. Two patients did not require any donor blood products. The median intensive care unit (ICU) and hospital lengths of stay (LOS) were two days and 10 days, respectively. The average peak serum lactate on CPB was 7.47 mmol/L and, at admission to the ICU, it was 3.37 mmol/L. Renal and respiratory failure developed in the salvage acute type A dissection patient. No other complications occurred in this series. CONCLUSIONS: Whole body perfusion as delivered through individually controlled dual-oxygenator circuitry allows maximum flexibility for hybrid aortic arch reconstruction. A modified circuit perfusion strategy may help to limit intra-operative metabolic derangements, providing improved clinical outcomes.

Innominate and Axillary Cannulation in Aortic Arch Surgery Provide Similar Neuroprotection.

BACKGROUND: Contemporaneous trends in cerebral protection during aortic arch surgery include moderate hypothermia (22°C-28°C) and continuous antegrade cerebral perfusion (ACP). Innominate artery cannulation is a simplified, alternative route for ACP; however, clinical outcomes have yet to be evaluated against the gold standard of axillary cannulation. METHODS: Between 2008 and 2015, 140 consecutive patients underwent hemiarch reconstruction with moderate hypothermia and continuous ACP at 2 institutions. Axillary cannulation was used in 74 patients (31.1% female, 64.8 ± 12.7 years) and the remaining 66 patients (24.2% female, 60.8 ± 10.5 years) had direct cannulation of the innominate artery for delivery of ACP. RESULTS: Although there were no statistically significant differences in complications, neurological events were almost twice as frequent in innominate (19.7%) than in axillary (10.8%; P = 0.142) whereas prolonged mechanical ventilation was much more common with axillary (17.6%) vs innominate (7.6%; P = 0.078). There were no mortalities in the axillary group and 1 in the innominate group (0% vs 1.5%; P > 0.471) and no statistically significant differences in any other postoperative complications or hospital length of stay. There was a reduction in total operating room time in the innominate group (axillary 454 ± 115 minutes, innominate 318 ± 125 minutes; P < 0.001), and in the matched subgroup analysis of patients who underwent Bentall and hemiarch reconstruction (axillary 456 ± 109 minutes, innominate 370 ± 106 minutes; P = 0.003). CONCLUSIONS: Axillary and innominate artery cannulation for ACP during proximal aortic arch reconstructive surgery resulted in similarly excellent neurological outcomes. Innominate artery cannulation might reduce total surgical time. Possible clinically relevant differences in neurological and respiratory complications require assessment in randomized controlled trials.

Invasive Methicillin-Resistant Staphylococcus Aureus Endocarditis Resulting in Right Ventricular Pseudoaneurysm and Fistulation to Previous Bypass Graft.

We describe the case of a 73-year-old man with methicillin-resistant Staphyloccocus aureus (MRSA) endocarditis, which developed into a right ventricular pseudoaneurysm that fistulated into a previous saphenous vein graft to his distal right coronary artery (RCA). The patient was taken for a redo sternotomy, surgical evacuation of the abscess, bovine pericardial patch reconstruction of the right ventricular free wall, and tricuspid valve repair. Despite our best efforts and a repair that appeared sufficient at the time of operation, the patient died of ischemic colitis on postoperative day 5. This case report highlights some of the surgical considerations for such a rare and lethal condition.

Defining the efficacy of aortic root enlargement procedures: a comparative analysis of surgical techniques.

BACKGROUND: Aortic root enlargement (ARE) procedures are believed to allow implantation of larger valve prostheses; however, little evidence exists to support the specific efficacy of various techniques. METHODS: Using a cadaveric model, 20 adult (72.4 ± 15.3 years) hearts were stratified into 4 groups based on annular diameter: <20 mm, 20-22 mm, 22-24 mm, and >24 mm. Each heart underwent an aortic valve replacement following a Nicks, Manougian, aortoventriculoplasty and modified Bentall procedure, with appropriate reversals between procedures. RESULTS: All 4 groups experienced similar increases in annular diameter (P = 0.43) and prosthesis size implanted (P = 0.51) with each enlargement technique. The Nicks, Manougian, modified Bentall and aortoventriculoplasty procedures enlarged the annulus by 0.43 ± 0.45 mm, 3.63 ± 0.95 mm, 0.78 ± 0.65 mm, and 6.08 ± 1.19 mm, respectively (P < 0.001). No significant change in prosthesis size was observed after the Nicks procedure (P = not significant). Increases of 1.3 ± 0.5, 1.3 ± 0.5, and 2.7 ± 0.6 prosthesis sizes were achieved with the Manougian, modified Bentall and aortoventriculoplasty techniques respectively (P < 0.001). CONCLUSIONS: ARE procedures appear equally efficacious in both small and larger aortic roots. Although all 4 ARE techniques increased the annular diameter, only the Manougian, modified Bentall and aortoventriculoplasty procedures allowed for the implantation of a larger prosthetic valve. The Nicks procedure, which is likely the most commonly performed ARE, does not allow for the implantation of a larger prosthesis. Surgeon preference and patient factors may help in selecting the most appropriate ARE technique, as the modified Bentall and Manougian procedures achieved similar increases in valve size.

Reduction of particle-induced osteolysis by interleukin-6 involves anti-inflammatory effect and inhibition of early osteoclast precursor differentiation.

The goal of this study was to define the anti-osteoclastogenic and/or anti-inflammatory role of IL-6 in inflammatory bone resorption using in vivo and in vitro methods. To this end, titanium particles were placed on murine calvaria, and bone resorption and osteoclast formation quantified in wild-type and IL-6(-/-) mice. In this model, calvarial bone loss and osteoclast formation were increased in titanium-treated IL-6(-/-) mice. Although basal numbers of splenic osteoclast precursors (OCP) were similar, IL-6(-/-) mice treated with particles in vivo had increased splenic OCP suggesting an enhanced systemic inflammatory response. In vitro osteoclastogenesis was measured using splenic (OCP) at various stages of maturation, including splenocytes from WT, IL-6(-/-) and TNFalpha transgenic mice. ELISA was used to measure TNFalpha production. IL-6 inhibited osteoclastogenesis in early OCP obtained from wild-type and IL-6(-/-) spleens. Pre-treatment of OCP with M-CSF for three days increased the CD11b(high)/c-Fms+ cell population, resulting in an intermediate staged OCP. Osteoclastogenesis was unaffected by IL-6 in M-CSF pre-treated and TNFalpha transgenic derived OCP. IL-6(-/-) splenocytes secreted greater concentrations of TNFalpha in response to titanium particles than WT; addition of exogenous IL-6 to these cultures decreased TNFalpha expression while anti-IL-6 antibody increased TNFalpha. While IL-6 lacks effects on intermediate staged precursors, the dominant in vivo effects of IL-6 appear to be related to strong suppression of early OCP differentiation and an anti-inflammatory effect targeting TNFalpha. Thus, the absence of IL-6 results in increased inflammatory bone loss.

Proinflammatory cytokines and metalloproteases are expressed in the subacromial bursa in patients with rotator cuff disease.

PURPOSE: The pathophysiology of subacromial impingement syndrome is poorly understood. We investigated the expression of inflammatory cytokines, metalloproteases, and the cyclooxygenases in the subacromial bursa in control patients and in patients with rotator cuff tear. TYPE OF STUDY: Basic science evaluation. METHODS: Eighteen patients undergoing shoulder surgery had a subacromial bursa biopsy examination. Patients were divided into 2 groups. Group I (study group) had 10 patients with a full-thickness rotator cuff tear (RCT). Group II (control group) had 8 patients. Seven of 8 underwent shoulder arthroscopy with anterior capsular reconstruction for instability; 1 of 8 underwent open reduction internal fixation for acute proximal humerus fracture. None of the patients in group II had any history of symptoms or signs consistent with subacromial impingement. H&E and immunohistochemical antibody (MMP-1, MMP-9, IL-1, IL-6, TNF-alpha, COX-1, and COX-2) stained specimens were examined by 2 blinded observers using a histologic scale (grade 0 = no staining to grade 4 = intense staining). RESULTS: Histologic evidence of inflammation was present in all patients with RCT (group I). No or mild inflammation was noted in group II. The average staining grade for inflammatory cytokines (IL-1, IL-6, TNF-alpha) and proteinases (MMP-1 and MMP-9) was significantly more pronounced in the RCT group (P < .001). Cyclooxygenase enzymes (COX-1 and COX-2) were also increased in group II (P < .001). CONCLUSIONS: A high level of expression of inflammatory cytokines, proteinases, and cyclooxygenase enzymes, known to produce a catabolic environment, is present in the subacromial bursa of patients with rotator cuff tear. CLINICAL RELEVANCE: These findings support the role of nonsteroidal anti-inflammatory drugs and corticosteroids in RCT treatment, and emphasize the importance of subacromial bursectomy to reduce inflammation in RCT surgery.

Radiographic changes in the patella following quadriceps turndown for revision total knee arthroplasty.

Quadriceps turndown is a technique that may be used to enhance exposure of the tight total knee arthroplasty (TKA), particularly in the revision scenario. This technique does, however, compromise the vascularity of the patella, with avascular necrosis (AVN) being a possible sequela. A modified Coonse-Adams quadriceps turndown was performed in 29 revision TKAs in 27 patients. Immediate preoperative and sequential postoperative radiographs were analyzed for changes in the patella, including sclerosis, flattening, fracture, and fragmentation, as evidence of possible AVN, and clinical scores were collected prospectively. Eight patellae had such radiographic changes. Despite a lack of corresponding worsening in clinical outcome in these patients, quadriceps turndown is shown to have a high risk of subsequent changes consistent with patellar AVN, and should be avoided when other available techniques can achieve satisfactory exposure.

PGE2 and IL-6 production by fibroblasts in response to titanium wear debris particles is mediated through a Cox-2 dependent pathway.

Aseptic loosening of orthopaedic implants is precipitated by wear debris-induced osteolysis. Central to this process are the pro-inflammatory mediators that are produced in response to wear by the fibroblastic cells, which comprise the majority of periprosthetic membranes. Since this pro-inflammatory cascade is mediated by a plethora of factors with redundant functions, it is imperative to establish a hierarchy. Two well-known fibroblast derived pro-inflammatory factors that stimulate wear debris-induced osteoclastic resorption are prostaglandin E2 (PGE2) and IL-6. However, their relationship to each other in this process is poorly defined. Here we show immunohistochemistry of retrieval membranes indicating that COX-2 is the principal cyclooxygenase responsible for PGE2 production in fibroblasts around failed implants. We also performed in vitro experiments with fibroblasts derived from wild-type (WT), COX-1 (-/-) and COX-2 (-/-) mice, which demonstrated that COX-2 is required for Ti wear debris-induced PGE2 production. Interestingly, COX-2 was also required for IL-6 production in these assays, which could be rescued by the addition of exogenous PGE2 (10(-6) M). Pharmacology studies that utilized the COX-1 selective inhibitor SC 560, the COX-2 selective inhibitor celecoxib, and the nonselective COX inhibitor indomethacin confirmed these results. Taken together, these results indicate that selective inhibition of prostaglandin signaling could favorably impact aseptic loosening beyond its direct effects on PGE2 synthesis, in that it inhibits downstream pro-inflammatory/pro-osteoclastic cytokine production.

Treatment of an intraoperative patellar fracture during revision total knee arthroplasty.

An intraoperative vertical patellar fracture occurred through a central osteolytic defect during removal of a metal-backed patellar component. The fracture was treated successfully with cerclage wire fixation and implantation of a cemented patellar component.