Del Nido cardioplegia for minimally invasive aortic valve replacement.

BACKGROUND: We analyzed the impact and safety of del Nido Cardioplegia (DNC) in patients undergoing minimally invasive aortic valve replacement (MIAVR). METHODS: We analyzed all isolated MIAVR replacements from 5/2013-6/2015 excluding re-operative patients. The approach was a hemi-median sternotomy in all patients. Patients were divided into two cohorts, those who received 4:1 crystalloid:blood DNC solution and those in whom standard 1:4 Buckberg-based cardioplegia (WBC) was used. One-to-one propensity case matching of DNC to WBC was performed based on standard risk factors and differences between groups were analyzed using chi-square and non-parametric methods. RESULTS: MIAVR was performed in 181 patients; DNC was used in 59 and WBC in 122. Case matching resulted in 59 patients per cohort. DNC was associated with reduced re-dosing (5/59 (8.5%) versus 39/59 (61.0%), P < 0.001) and less total cardioplegia volume (1290 ± 347 mL vs 2284 ± 828 mL, P < 0.001). Antegrade cardioplegia alone was used in 89.8% (53/59) of DNC patients versus 33.9% (20/59) of WBC patients (P < 0.001). Median bypass and aortic cross-clamp times were similar. Clinical outcomes were similar with respect to post-operative hematocrit, transfusion requirements, need for inotropic/pressor support, duration of intensive care unit stay, re-intubation, length of stay, new onset atrial fibrillation, and mortality. CONCLUSIONS: Del Nido cardioplegia usage during MIAVR minimized re-dosing and the need for retrograde delivery. Patient safety was not compromised with this technique in this group of low-risk patients undergoing MIAVR.

Robotic Transcatheter Mitral Valve Replacement Using the Sapien XT in the Setting of Severe Mitral Annular Calcification.

We describe the use of the Sapien XT, placed in the mitral position using a totally endoscopic robotic approach in a 76-year-old man with extensive circumferential mitral calcifications and severe stenosis. The patient was at high risk for traditional open surgery and a large mitral valve annulus prevented safe transcatheter deployment due to size mismatch. Our novel approach offered a minimally invasive technique for native mitral valve replacement in a high-risk patient with anatomical constraints prohibitive to conventional approaches. doi: 10.1111/jocs.12737 (J Card Surg 2016;31:303-305).

Residency characteristics that matter most to plastic surgery applicants: a multi-institutional analysis and review of the literature.

PURPOSE: The National Residency Matching Program Match is a very unique process in which applicants and programs are coupled to each other based on a ranking system. Although several studies have assessed features plastic surgery programs look for in applicants, no study in the present plastic surgery literature identifies which residency characteristics are most important to plastic surgery applicants. Therefore, we sought to perform a multi-institutional assessment as to which factors plastic surgery residency applicants consider most important when applying for residency. METHODS: A validated and anonymous questionnaire containing 37 items regarding various program characteristics was e-mailed to 226 applicants to New York University, Albany, University of Michigan, and University of Southern California plastic surgery residency programs. Applicants were asked to rate each feature on a scale from 1 to 10, with 10 being the most important. The 37 variables were ranked by the sum of the responses. The median rating and interquartile range as well as the mean for each factor was then calculated. A Wilcoxon signed rank test was used to compare medians in rank order. RESULTS: A total of 137 completed questionnaires were returned, yielding a 61% response rate. The characteristics candidates considered most important were impressions during the interview, experiences during away rotations, importance placed on resident training/support/mentoring by faculty, personal experiences with residents, and the amount of time spent in general surgery. The characteristics candidates considered least important were second-look experiences, compensation/benefits, program reputation from Internet forums, accessibility of program coordinator, opportunity for laboratory research, and fellowship positions available at the program. CONCLUSIONS: Applicants value personal contact and time spent in general surgery when selecting residency programs. As the number of integrated programs continues to grow, programs will benefit from learning what factors their applicants value most.

Force generated by actomyosin contraction builds bridges between adhesive contacts.

Extracellular matrices in vivo are heterogeneous structures containing gaps that cells bridge with an actomyosin network. To understand the basis of bridging, we plated cells on surfaces patterned with fibronectin (FN)-coated stripes separated by non-adhesive regions. Bridges developed large tensions where concave cell edges were anchored to FN by adhesion sites. Actomyosin complexes assembled near those sites (both actin and myosin filaments) and moved towards the centre of the non-adhesive regions in a treadmilling network. Inhibition of myosin-II (MII) or Rho-kinase collapsed bridges, whereas extension continued over adhesive areas. Inhibition of actin polymerization (latrunculin-A, jasplakinolide) also collapsed the actomyosin network. We suggest that MII has distinct functions at different bridge regions: (1) at the concave edges of bridges, MIIA force stimulates actin filament assembly at adhesions and (2) in the body of bridges, myosin cross-links actin filaments and stimulates actomyosin network healing when breaks occur. Both activities ensure turnover of actin networks needed to maintain stable bridges from one adhesive region to another.

Composite scaffold provides a cell delivery platform for cardiovascular repair.

Control over cell engraftment, survival, and function remains critical for heart repair. We have established a tissue engineering platform for the delivery of human mesenchymal progenitor cells (MPCs) by a fully biological composite scaffold. Specifically, we developed a method for complete decellularization of human myocardium that leaves intact most elements of the extracellular matrix, as well as the underlying mechanical properties. A cell-matrix composite was constructed by applying fibrin hydrogel with suspended cells onto decellularized sheets of human myocardium. We then implanted this composite onto the infarct bed in a nude rat model of cardiac infarction. We next characterized the myogenic and vasculogenic potential of immunoselected human MPCs and demonstrated that in vitro conditioning with a low concentration of TGF-ß promoted an arteriogenic profile of gene expression. When implanted by composite scaffold, preconditioned MPCs greatly enhanced vascular network formation in the infarct bed by mechanisms involving the secretion of paracrine factors, such as SDF-1, and the migration of MPCs into ischemic myocardium, but not normal myocardium. Echocardiography demonstrated the recovery of baseline levels of left ventricular systolic dimensions and contractility when MPCs were delivered via composite scaffold. This adaptable platform could be readily extended to the delivery of other reparative cells of interest and used in quantitative studies of heart repair.

Impella LP 2.5 for left ventricular unloading during venoarterial extracorporeal membrane oxygenation support.

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is commonly used as a means of support for acute cardiopulmonary failure. In the setting of severe left ventricular (LV) dysfunction, VA-ECMO may be complicated by LV distension, which can lead to pulmonary edema and compromise myocardial recovery. Traditional decompression methods carry significant risk. We report the use of the Impella LP 2.5 for LV decompression in a 70-year-old man with decompensated heart failure who was placed on VA-ECMO for cardiogenic shock with severe pulmonary edema and respiratory failure. Both devices were successfully weaned on day 5 of VA-ECMO support, after myocardial recovery.

Advanced experience allows robotic mitral valve repair in the presence of extensive mitral annular calcification.

OBJECTIVE: Mitral annular calcification is underdiagnosed in patients with mitral regurgitation. After excision, it may require reconstruction of the atrioventricular groove and decreases the probability of valve repair. We reviewed the safety and efficacy of totally endoscopic robotic mitral valve repair in the presence of mitral annular calcification, with an emphasis on pathology and repair techniques. METHODS: Between May 2011 and August 2017, the same 2-surgeon team attempted totally endoscopic robotic mitral valve repair in 64 mitral annular calcification cases, accounting for 12.8% of our experience. Mitral annular calcification associated with a calcified posterior leaflet was not considered for totally endoscopic robotic mitral valve repair. When possible, the mitral annular calcification was excised en bloc using electrocautery, the posterior leaflet separated from the mitral annular calcification and spared, the atrioventricular groove was reconstructed, the posterior leaflet was reattached to the neoannulus, and the repair was completed with annuloplasty. RESULTS: The median age of patients was 65 years, with 21 (32.8%) aged less than 60 years, and 34 (53.1%) were women. The etiology was Barlow's disease in 54 patients (84%). Repair was converted to replacement in 2 patients (3.1%). Cryoablation was performed in 8 patients (12.5%), hybrid percutaneous coronary intervention was performed in 5 patients (7.8%), and tricuspid annuloplasty was performed in 2 patients (3.1%). Median aortic occlusion was 122 minutes, excluding cases with concomitant tricuspid repair. Thirty-three patients (52%) were extubated in the operating room. The median length of stay was 4 days. Residual mitral regurgitation on discharge transthoracic echocardiogram was none to mild in all patients. None of the patients had a perioperative stroke or needed a pacemaker. Thirty-day mortality was 2 (3.1%). CONCLUSIONS: Mitral annular calcification is present in a significant percentage of patients with mitral regurgitation, especially in Barlow's disease, including younger patients. By using a variety of repair techniques, totally endoscopic robotic mitral valve repair can be performed safely and effectively in most mitral annular calcification cases with a noncalcified posterior leaflet.

Percutaneous cell delivery into the heart using hydrogels polymerizing in situ.

Heart disease is the leading cause of death in the US. Following an acute myocardial infarction, a fibrous, noncontractile scar develops, and results in congestive heart failure in more than 500,000 patients in the US each year. Muscle regeneration and the induction of new vascular growth to treat ischemic disorders of the heart can have significant therapeutic implications. Early studies in patients with chronic ischemic systolic left ventricular dysfunction (SLVD) using skeletal myoblasts or bone marrow-derived cells report improvement in left ventricular ejection function (LVEF) and clinical status, without notable safety issues. Nonetheless, the efficacy of cell transfer for cardiovascular disease is not established, in part due to a lack of control over cell retention, survival, and function following delivery. We studied the use of biocompatible hydrogels polymerizable in situ as a cell delivery vehicle, to improve cell retention, survival, and function following delivery into the ischemic myocardium. The study was conducted using human bone marrow-derived mesenchymal stem cells and fibrin glue, but the methods are applicable to any human stem cells (adult or embryonic) and a wide range of hydrogels. We first evaluated the utility of several commercially available percutaneous catheters for delivery of viscous cell/hydrogel suspensions. Next we characterized the polymerization kinetics of fibrin glue solutions to define the ranges of concentrations compatible with catheter delivery. We then demonstrate the in vivo effectiveness of this preparation and its ability to increase cell retention and survival in a nude rat model of myocardial infarction.

Aggressive tissue aortic valve replacement in younger patients and the risk of re-replacement: Implications from microsimulation analysis.

OBJECTIVE: Advances in transcatheter aortic valve replacement have led to the consideration of tissue aortic valve replacement in younger patients. Part of this enthusiasm is the presumption that younger patients would have more flexibility in future treatment options, such as a primary surgical aortic valve replacement followed later by transcatheter aortic valve replacement(s) (valve-in-valve), vice versa, or other permutations. We created a microsimulation model using published longevity of tissue valves to predict the outcomes of patients after primary tissue surgical aortic valve replacement. METHODS: The model calculated survival by incorporating annual mortality (Social Security Administration) and mortality from re-replacements (Society of Thoracic Surgeons) in patients with surgical aortic valve replacement. Freedom from reoperation for structural valve degeneration incorporated best published data to determine the annual risk of re-replacement for structural valve degeneration based on implant duration and stratified by patient age. A constant rate of re-replacement for nonstructural valve degeneration indications was also incorporated. Each simulation was performed for 50,000 individuals. Kaplan-Meier curves were generated to represent survival. All simulations were run within the MATLAB environment (The MathWorks, Inc, Natick, Mass). RESULTS: Earlier decades of life at primary surgical aortic valve replacement were associated with higher incidences of re-replacements and especially multiple re-replacements. For those patients receiving a primary tissue surgical aortic valve replacement at age 50 years, 57.2% will require a second valve, 18.0% will require a third valve, and 1.6% will require a fourth valve with average operative mortalities of 2.9%, 4.8%, and 7.3%, respectively. A 50-year-old patient at primary surgical aortic valve replacement has a 13.1% chance of re-replacement before turning 60 years of age. CONCLUSIONS: Microsimulation incorporates changing hazards to estimate the risk of aortic valve re-replacement in patients undergoing tissue surgical aortic valve replacement and may be a starting point for patient education and health care economic planning.

Ninety-Day Readmissions of Bundled Valve Patients: Implications for Healthcare Policy.

Medicare's Bundle Payment for Care Improvement (BPCI) Model 2 groups reimbursement for valve surgery into 90-day episodes of care, which include operative costs, inpatient stay, physician fees, postacute care, and readmissions up to 90 days postprocedure. We analyzed our BPCI patients' 90-day outcomes to understand the late financial risks and implications of the bundle payment system for valve patients. All BPCI valve patients from October 2013 (start of risk-sharing phase) to December 2015 were included. Readmissions were categorized as early (≤30 days) or late (31-90 days). Data were collected from institutional databases as well as Medicare claims. Analysis included 376 BPCI valve patients: 202 open and 174 transcatheter aortic valves (TAVR). TAVR patients were older (83.6 vs 73.8 years; P = 0.001) and had higher Society of Thoracic Surgery predicted risk (7.1% vs 2.8%; P = 0.001). Overall, 18.6% of patients (70/376) had one-or-more 90-day readmission, and total claim was on average 51% greater for these patients. Overall readmissions were more common among TAVR patients (22.4% (39/174) vs 15.3% (31/202), P = 0.052) as was late readmission. TAVR patients had significantly higher late readmission claims, and early readmission was predictive of late readmission for TAVR patients only (P = 0.04). Bundled claims for a 90-day episode of care are significantly increased in patients with readmissions. TAVR patients represent a high-risk group for late readmission, possibly a reflection of their chronic disease processes. Being able to identify patients at highest risk for 90-day readmission and the associated claims will be valuable as we enter into risk-bearing episodes of care agreements with Medicare.

A Contemporary Approach to Reoperative Aortic Valve Surgery: When is Less, More?

OBJECTIVE: Although the benefits of minimally invasive valvular surgery are well established, the applicability of extending these techniques to reoperative aortic valve surgery is unknown. We evaluated our experience with a minimally invasive approach to this patient population. METHODS: From January 2010 to September 2015, 21 patients underwent reoperative isolated aortic valve replacement via a minimally invasive approach by a single surgeon. All patients had preoperative evaluation with computerized tomography and coronary catheterization. Surgical approaches were right anterior thoracotomy (6/21) or upper hemisternotomy (15/21). Central aortic cannulation was preferred with femoral artery cannulation used in four patients (19%). In patients with left internal mammary artery (LIMA) grafts, no attempt to dissect or occlude the graft was made. Cold blood cardioplegia was administered antegrade (12/21) or retrograde (9/21); systemic cooling with a mean low temperature of 27.5 °C was employed. RESULTS: Mean age was 75.1 years with a range from 33 to 92 years, and 67% (14/21) were male. All procedures were completed with a minimally invasive approach. Mean ± SD cross-clamp time was 51.5 ± 9.2 minutes. Fourteen patients had patent LIMA grafts. No aortic, LIMA, or cardiac injuries occurred. There were no hospital deaths nor occurrences of perioperative myocardial infarction, stroke, wound infection, renal failure, or endocarditis/sepsis. One patient required a reoperation for bleeding. Sixty-two percent of patients were discharged to home; mean ± SD length of stay was 6 ± 3 days. CONCLUSIONS: With appropriate preoperative evaluation and careful surgical planning, a minimally invasive approach to reoperative aortic valve surgery can be performed in a safe and effective manner.

Reengineering valve patients' postdischarge management for adapting to bundled payment models.

BACKGROUND: Bundled Payments for Care Improvement (BPCI) initiatives were developed by Medicare in an effort to reduce expenditures while preserving quality of care. Payment model 2 reimburses based on a target price for 90-day episode of care postprocedure. The challenge for valve patients is the historically high (>35%) 90-day readmission rate. We analyzed our institutional cardiac surgical service line adaptation to this initiative. METHODS: On May 1, 2015, we instituted a readmission reduction initiative (RRI) that included presurgical risk stratification, comprehensive predischarge planning, and standardized postdischarge management led by cardiac nurse practitioners (CNPs) who attempt to guide any postdischarge encounters (PDEs). A prospective database also was developed, accruing data on all cardiac surgery patients discharged after RRI initiation. We analyzed detailed PDEs for all valve patients with complete 30-day follow-up through November 2015. RESULTS: Patients included 219 surgical patients and 126 transcatheter patients. Sixty-four patients had 79 PDEs. Of these 79 PDEs, 46 (58.2%) were guided by CNPs. PDEs were due to fluid overload/effusion (21, 27%), arrhythmia (17, 22%), bleeding/thromboembolic events (13, 16%), and falls/somatic complaints (12, 15%). Thirty-day readmission rate was 10.1% (35/345). Patients with transcatheter aortic valve replacement had a higher rate of readmission than surgical patients (15.0% vs 6.9%), but were older with more comorbidities. The median readmission length of stay was 2.0 days (interquartile range 1.0-5.0 days). Compared with 2014, the 30-day readmission rate for BPCI decreased from 18% (44/248) to 11% (20/175), P = .05. CONCLUSIONS: Our reengineering of pre/postdischarge management of BPCI valve patients under tight CNP control has significantly reduced costly 30-day readmissions in this high-risk population.