Matthew A. Schechter

Regional versus general anesthesia for carotid endarterectomy: The American College of Surgeons National Surgical Quality Improvement Program perspective

BACKGROUND The ideal anesthetic technique for carotid endarterectomy remains a matter of debate. This study used the American College of Surgeons National Surgical Quality Improvement Program to evaluate the influence of anesthesia modality on outcomes after carotid endarterectomy. METHODS Postoperative outcomes were compared for American College of Surgeons National Surgical Quality Improvement Program patients undergoing carotid endarterectomy between 2005 and 2009 with either general or regional anesthesia. A separate analysis was performed on a subset of patients matched on propensity for undergoing carotid endarterectomy with regional anesthesia. RESULTS For the entire sample of 24,716 National Surgical Quality Improvement Program patients undergoing carotid endarterectomy and the propensity-matched cohort of 8,050 patients, there was no difference in the 30-day postoperative composite stroke/myocardial infarction/death rate based on anesthetic type. Within the matched cohort, the rate of other complications did not differ (2.8% regional vs. 3.6% general anesthesia; P = .07), but patients receiving regional anesthesia had shorter operative (99 ± 36 minutes vs 119 ± 53 minutes; P < .0001) and anesthesia times (52 ± 29 minutes vs. 64 ± 37 minutes; P < .0001) and were more likely to be discharged the next day (77.0% vs 64.4%; P < .0001). CONCLUSION Anesthesia technique does not impact patient outcomes after carotid endarterectomy, but may influence overall cost of care.

Antegrade versus retrograde cerebral perfusion for hemiarch replacement with deep hypothermic circulatory arrest: Does it matter? A propensity-matched analysis

OBJECTIVE The choice of cerebral perfusion strategy for aortic arch surgery has been debated, and the superiority of antegrade (ACP) or retrograde (RCP) cerebral perfusion has not been shown. We examined the early and late outcomes for ACP versus RCP in proximal (hemi-) arch replacement using deep hypothermic circulatory arrest (DHCA). METHODS A retrospective analysis of a prospectively maintained database was performed for all patients undergoing elective and nonelective hemiarch replacement at a single referral institution from June 2005 to February 2013. Total arch cases were excluded to limit the analysis to shorter DHCA times and a more uniform patient population for whom clinical equipoise regarding ACP versus RCP exists. A total of 440 procedures were identified, with 360 (82%) using ACP and 80 (18%) using RCP. The endpoints included 30-day/in-hospital and late outcomes. A propensity score with 1:1 matching of 40 pre- and intraoperative variables was used to adjust for differences between the 2 groups. RESULTS All 80 RCP patients were propensity matched to a cohort of 80 similar ACP patients. The pre- and intraoperative characteristics were not significantly different between the 2 groups after matching. No differences were found in 30-day/in-hospital mortality or morbidity outcomes. The only significant difference between the 2 groups was a shorter mean operative time in the RCP cohort (P = .01). No significant differences were noted in late survival (P = .90). CONCLUSIONS In proximal arch operations using DHCA, equivalent early and late outcomes can be achieved with RCP and ACP, although the mean operative time is significantly less with RCP, likely owing to avoidance of axillary cannulation. Questions remain regarding comparative outcomes with straight DHCA and lesser degrees of hypothermia.

Outcomes in kidney transplant recipients from older living donors.

Background Previous studies demonstrate that graft survival from older living kidney donors (LD; age >60 years) is worse than younger LD but similar to deceased standard criteria donors (SCD). Limited sample size has precluded more detailed analyses of transplants from older LD. Methods Using the United Network for Organ Sharing database from 1994 to 2012, recipients were categorized by donor status: SCD, expanded criteria donor (ECD), or LD (by donor age: <60, 60–64, 65–69, ≥70 years). Adjusted models, controlling for donor and recipient risk factors, evaluated graft and recipient survivals. Results Of 250,827 kidney transplants during the study period, 92,646 were LD kidneys, with 4.5% of these recipients (n = 4,186) transplanted with older LD kidneys. The use of LD donors 60 years or older increased significantly from 3.6% in 1994 to 7.4% in 2011. Transplant recipients with older LD kidneys had significantly lower graft and overall survival compared to younger LD recipients. Compared to SCD recipients, graft survival was decreased in recipients with LD 70 years or older, but overall survival was similar. Older LD kidney recipients had better graft and overall survival than ECD recipients. Conclusions As use of older kidney donors increases, overall survival among kidney transplant recipients from older living donors was similar to or better than SCD recipients, better than ECD recipients, but worse than younger LD recipients. With increasing kidney donation from older adults to alleviate profound organ shortages, the use of older kidney donors appears to be an equivalent or beneficial alternative to awaiting deceased donor kidneys.

Retrieval of iatrogenic intravascular foreign bodies

Malposition, embolization, fracture, and migration of endovascular devices are unfortunate consequences of endovascular intervention and will be encountered at some point by nearly every practitioner. The existing literature on foreign body retrieval consists of large single-institution series and case reports. We provide an overview of this recent literature, clarifying what devices are being lost, what symptoms occur as a result, and how retrieval is being performed. We have identified all case series and case reports since the year 2000, summarized the results, and made some general observations and recommendations that may be useful to the practitioner faced with the prospect of retrieving a fractured medical device, malpositioned coil, or migrated inferior vena cava filter.

Spontaneously Breathing Extracorporeal Membrane Oxygenation Support Provides the Optimal Bridge to Lung Transplantation.

Background Extracorporeal membrane oxygenation (ECMO) is being increasingly used as a bridge to lung transplantation. Small, single-institution series have described increased success using ECMO in spontaneously breathing patients compared with patients on ECMO with mechanical ventilation, but this strategy has not been evaluated on a large scale. Methods Using the United Network for Organ Sharing database, all adult patients undergoing isolated lung transplantation from May 2005 through September 2013 were identified. Patients were categorized by their type of pretransplant support: no support, ECMO only, invasive mechanical ventilation (iMV) only, and ECMO + iMV. Kaplan-Meier survival analysis with log-rank testing was performed to compare survival based on type of preoperative support. A Cox regression model was used to determine whether type of preoperative support was independently associated with survival, using previously established predictors of survival as covariates. Results Approximately 12,403 primary adult pulmonary transplantations were included in this analysis. Sixty-five patients (0.52%) were on ECMO only, 612 (4.93%) required only iMV, 119 (0.96%) were on ECMO + iMV, and the remaining 11,607 (94.6%) required no invasive support before transplantation. One-year survival was decreased in all patients requiring support, regardless of type. However, mid-term survival was similar between patients on ECMO alone and those not on support but significantly worse with patients requiring iMV only or ECMO + iMV. In multivariable analysis, ECMO + iMV and iMV alone were independently associated with decreased survival compared with nonsupport patients, whereas ECMO alone was not significant. Conclusions In patients with worsening pulmonary disease awaiting lung transplantation, those supported via ECMO with spontaneous breathing demonstrated improved survival compared with other bridging strategies.

Phosphoproteomic Profiling of Human Myocardial Tissues Distinguishes Ischemic from Non-Ischemic End Stage Heart Failure

The molecular differences between ischemic (IF) and non-ischemic (NIF) heart failure are poorly defined. A better understanding of the molecular differences between these two heart failure etiologies may lead to the development of more effective heart failure therapeutics. In this study extensive proteomic and phosphoproteomic profiles of myocardial tissue from patients diagnosed with IF or NIF were assembled and compared. Proteins extracted from left ventricular sections were proteolyzed and phosphopeptides were enriched using titanium dioxide resin. Gel- and label-free nanoscale capillary liquid chromatography coupled to high resolution accuracy mass tandem mass spectrometry allowed for the quantification of 4,436 peptides (corresponding to 450 proteins) and 823 phosphopeptides (corresponding to 400 proteins) from the unenriched and phospho-enriched fractions, respectively. Protein abundance did not distinguish NIF from IF. In contrast, 37 peptides (corresponding to 26 proteins) exhibited a ≥2-fold alteration in phosphorylation state (p<0.05) when comparing IF and NIF. The degree of protein phosphorylation at these 37 sites was specifically dependent upon the heart failure etiology examined. Proteins exhibiting phosphorylation alterations were grouped into functional categories: transcriptional activation/RNA processing; cytoskeleton structure/function; molecular chaperones; cell adhesion/signaling; apoptosis; and energetic/metabolism. Phosphoproteomic analysis demonstrated profound post-translational differences in proteins that are involved in multiple cellular processes between different heart failure phenotypes. Understanding the roles these phosphorylation alterations play in the development of NIF and IF has the potential to generate etiology-specific heart failure therapeutics, which could be more effective than current therapeutics in addressing the growing concern of heart failure.

Pseudoaneurysm Formation After Medtronic Freestyle Porcine Aortic Bioprosthesis Implantation: A Word of Caution

BACKGROUND A growing literature describes aneurysmal deterioration after implantation of the stentless porcine aortic Medtronic Freestyle bioprosthesis (MFB; Medtronic Inc, Minneapolis, MN), with some suggesting inadequate tissue fixation with immune response as a cause. However, disjointed reports make the significance of these findings difficult to interpret. We address this concern by aggregating available data. METHODS We reviewed institutional data, the Food and Drug Administrations Manufacturer and User Facility Device Experience registry, and the medical literature for mention of aneurysm or pseudoaneurysm after MFB. Case details were aggregated, and the rate of aneurysmal deterioration was estimated. Immunohistopathologic examination of institutional explanted specimens was performed to elucidate a cause. RESULTS We found 42 cases of aneurysmal deterioration with adequate detail for analysis; all occurred with full root replacement and valve sizes ranging from 23 to 29 mm. The rate of aneurysmal deterioration considering all data sources was 1.1% (9 of 851; 95% confidence interval, 0.5% to 2.0%) vs 4.7% (4 of 86; 95% confidence interval, 1.3% to 11.5%) at our institution, where yearly surveillance imaging is performed. Rate of aneurysmal deterioration appeared constant until 5 years after the operation; however, events are reported out to 10 years. Consistent with previous reports, histopathology demonstrated an immune cell infiltrate in areas of MFB wall breakdown. CONCLUSIONS Aneurysmal deterioration is an increasingly described complication of MFB implantation as a full root, with an incidence as high as 4.7%. Given the observed immune reaction and lack of occurrence in smaller (19-mm and 21-mm) valve sizes, inadequate pressure fixation of larger valves is a potential etiology. Patients with MFB require annual surveillance imaging, and consideration of this complication should factor into preoperative decision making because treatment mandates redo root replacement, which may not be feasible in high-risk patients.

Improved Early Survival With a Nonsternotomy Approach for Continuous-Flow Left Ventricular Assist Device Replacement

BACKGROUND Even in the modern era of continuous-flow left ventricular assist devices (CF LVADs), device replacement may be required. Nonsternotomy (NS) approaches are being used more commonly for replacement procedures. Outcomes after this less invasive approach compared with those after a reoperative sternotomy (RS) have not been extensively studied. Furthermore, the clinical impact of concurrent cardiac procedures during device replacement has not been examined. METHODS From 2005 to 2013, all consecutive implantable LVAD procedures were reviewed, and those using CF devices as both the initial and replacement device were identified. These CF LVAD replacement procedures were divided into those using an RS and those using an NS approach. Periprocedural morbidity and mortality were compared between the groups. RESULTS A total of 42 CF LVAD replacements were performed in 39 patients, with 20 using an RS approach and 22 using an NS approach. Eleven of the 20 replacement procedures performed by RS included a concurrent cardiac procedure. Relative to the RS cohort, the NS approach was associated with shorter cardiopulmonary bypass time, reduced length of mechanical ventilation, decreased transfusion requirements, less inotropic support, decreased incidence of right ventricular (RV) dysfunction, and shorter intensive care unit (ICU) and overall hospital stays. An NS approach was also associated with improved 30- and 90-day survival (100% versus 79.0% in the RS group; p = 0.048). RS replacement procedures appeared to be associated with increased morbidity, regardless of whether they included concurrent cardiac procedures. CONCLUSIONS Patients who did not require an RS approach and who underwent CF LVAD replacement through an NS approach had improved survival and reduced morbidity compared with those who required an RS.

Outcomes after implantable left ventricular assist device replacement procedures.

As the duration of support increases for patients with continuous flow left ventricular assist devices (LVADs), device replacement may still be necessary for a variety of indications. Outcomes after replacement LVAD surgeries have not been extensively described, and whether these patients experience outcomes similar to primary LVAD implant patients remains unclear. From 2003 to 2012, 342 consecutive implantable LVAD procedures took place at a single institution, of which 201 were considered destination therapy. Within this larger group, 30 patients underwent 35 replacement procedures. The three major indications for replacement LVAD procedures were mechanical/electrical failure (57%), hemolysis/thrombosis (29%), and infection (14%). Propensity matching using preoperative characteristics was used to generate a primary implant control group to determine the impact of the replacement status on outcomes. Thirty-day and 1-year survival after LVAD replacement was 90% and 48%, respectively. Survival outcomes were worse for patients undergoing device replacement compared with the matched primary cohort (p = 0.03). The need for transfusion and the incidence of postoperative right ventricular and renal dysfunction were similar between the two groups, as was length of hospitalization. There was no difference between the rates of postoperative infection or stroke. Emergent replacement procedures had a higher mortality than those done nonemergently. Given these findings, earlier timing for replacement, temporary stabilization with an extracorporeal device, and use of a nonsternotomy surgical approach should be investigated as strategies to improve outcomes.

Changes in Risk Profile and Outcomes of Patients Undergoing Surgical Aortic Valve Replacement From the Pre– to Post–Transcatheter Aortic Valve Replacement Eras

BACKGROUND With initiation of transcatheter aortic valve replacement (TAVR) programs, centers may see changes in surgical aortic valve replacement (SAVR) populations and related outcomes because of more high-risk patients undergoing TAVR rather than SAVR. Little data exist on the potential changes in the risk profiles and outcomes of SAVR patients from the pre- to post-TAVR eras. As such, this study sought to evaluate changes in the SAVR population at a tertiary referral center after TAVR program initiation. METHODS Using a single-center valve surgical database, annual volume, patient characteristics, operative details, and predicted and observed mortality for patients undergoing isolated SAVR or SAVR + coronary artery bypass grafting (CABG) from 2006 to 2013 were evaluated. Patients were divided into 3 eras: (1) pre-TAVR (January 2006-June 2009), (2) transition (July 2009-March 2011), and (3) TAVR (April 2011-June 2013). The primary analysis compared predicted and observed mortality in pre-TAVR and TAVR eras. RESULTS From 2006 to 2013, 1,380 SAVR patients were identified, with 505 (36.6%), 330 (23.9%), and 545 (39.5%) patients from the pre-TAVR, transition, and TAVR eras, respectively. SAVR case volume increased from 131 to 256 cases per year (95.4% increase) from the pre-TAVR to the post-TAVR eras. Predicted risk of mortality (PROM) for SAVR patients from the pre-TAVR to TAVR eras by The Society of Thoracic Surgeons (STS)-PROM was stable near 3.8% (p = 0.82). Crude 30-day SAVR mortality trended down from 2.8% in the pre-TAVR era to 1.5% in the post-TAVR era (p = 0.23). CONCLUSIONS Consistent with previous studies, initiation of a TAVR program was associated with increased SAVR volume. Risk profiles for SAVR patients in the TAVR era remained similar by the STS-PROM, indicating generally stable risk among surgical patients after launching a TAVR program. These data suggest that significant changes in the risk profiles of SAVR patients should not be expected with the initiation of a TAVR program. Further research will need to reevaluate these changes once TAVR becomes more widely available.