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Whether all patients will require an opioid prescription after cardiac surgery is unknown. We performed a multicenter analysis to identify patient predictors of not receiving an opioid prescription at the time of discharge home after cardiac surgery.Opioid-naïve patients undergoing coronary artery bypass grafting and/or valve surgery through a sternotomy at 10 centers from January to December 2019 were identified retrospectively from a prospectively maintained data set. Opioid-naïve was defined as not taking opioids at the time of admission. The primary outcome was discharge without an opioid prescription. Mixed-effects logistic regression was performed to identify predictors of discharge without an opioid prescription, and postdischarge opioid prescribing was monitored to assess patient tolerance of discharge without an opioid prescription.Among 1924 eligible opioid-naïve patients, mean age was 64 ± 11 years, and 25% were women. In total, 28% of all patients were discharged without an opioid prescription. On multivariable analysis, older age, longer length of hospital stay, and undergoing surgery during the last 3 months of the study were independent predictors of discharge without an opioid prescription, whereas depression, non-Black and non-White race, and using more opioid pills on the day before discharge were independent predictors of receiving an opioid prescription. Among patients discharged without an opioid prescription, 1.8% (10 of 547) were subsequently prescribed an opioid.Discharging select patients without an opioid prescription after cardiac surgery appears well tolerated, with a low incidence of postdischarge opioid prescriptions. Increasing the number of patients discharged without an opioid prescription may be an area for quality improvement.

Composite performance measures for the Society of Thoracic Surgeons (STS) Adult Cardiac Surgery Database participants (typically hospital departments or practice groups) are currently available only for individual procedures. To assess overall participant performance, STS has developed a composite metric encompassing the most common adult cardiac procedures.Analyses included 1-year (July 1, 2018 to June 30, 2019) and 3-year (July 1, 2016 to June 30, 2019) time windows. Operations included isolated coronary artery bypass grafting (CABG), isolated aortic valve replacement (AVR), isolated mitral valve repair (MVr) or replacement (MVR), AVR + CABG, MVr or MVR + CABG, AVR + MVr or MVR, and AVR + (MVr or MVR) + CABG. The composite was estimated using Bayesian hierarchical models with risk-adjusted mortality and morbidity end points. Star ratings were based upon whether the 95% credible interval of a participant's score was entirely lower than (1 star), overlapping (2 star), or higher than (3 star) the STS average composite score.The North American procedural mix in the 3-year study cohort was as follows: 448 569 CABG, 72 067 AVR, 35 708 MVr, 29 953 MVR, 45 254 AVR + CABG, 12 247 MVr + CABG, 10 118 MVR + CABG, 3743 AVR + MVr, 6846 AVR + MVR, and 3765 AVR + (MVr or MVR) + CABG. Mortality and morbidity weightings were similar for 1- and 3-year analyses (76% and 24% [3-year]), as were composite score distributions (median, 94.7%; interquartile range, 93.6% to 95.6% [3-year]). The 3-year time frame was selected for operational use because of higher model reliability (0.81 [0.78-0.83]) and better outlier discrimination (26%, 3 star; 16%, 1 star). Risk-adjusted outcomes for 1-, 2-, and 3-star programs were 4.3%, 3.0%, and 1.8% mortality and 18.4%, 13.4%, and 9.7% morbidity, respectively.The STS participant-level, multiprocedural composite measure provides comprehensive, highly reliable, overall quality assessment of adult cardiac surgery practices.

Introduction: It’s unknown if patients with Bicuspid Aortic Valve (BAV) endocarditis behave differently compared to Tricuspid Aortic Valve (TAV), and if BAV patients are more susceptible to aortic valve endocarditis. Hypothesis: We aimed to distinguish BAV and TAV infectious endocarditis, including the short and long-term outcomes after surgical treatment. Methods: From 1997-2017, 336 patients underwent surgical treatment for aortic valve endocarditis, including 63(19%) BAV, which is 10-20 times higher than the BAV incidence in the general population (1-2%), and 273(81%) TAV endocarditis. Results: Postoperatively, the BAV group had significant shorter intubation time, and less renal failure on dialysis compared to TAV group. There was no compelling difference in postoperative stroke, sepsis, pacemaker requirement and in-hospital mortality [3/65(4.6%) vs. 19/283(6.7%)] between groups. The 10-year survival was better in the BAV group than the TAV group (62% vs. 33%, p=0.004) (Figure). The significant risk factors for late mortality were renal failure on dialysis [hazard ratio (HR)=2], intravenous drug user (HR=2.4), congestive heart failure (HR=1.6), previous coronary artery bypass (HR=1.8) and liver disease (HR=2.4), all p Conclusions: In conclusion, BAV patients have a higher likelihood of infectious endocarditis requiring surgery at a younger age than TAV patients, but similar outcomes. Strong consideration of utilizing prophylactic antibiotics and early surgical treatment for BAV patients, to lower the likelihood of aortic valve endocarditis.

Objective The study objective was to provide evidence for choosing a bioprosthesis in treating patients with active aortic valve endocarditis. Methods From 1998 to 2017, 265 patients with active aortic valve endocarditis underwent aortic valve replacement with a stented valve (n = 97, 37%) or a stentless valve (n = 168, 63%) with further breakdown into inclusion technique (n = 142, 85%) or total root replacement (n = 26, 15%). Data were obtained from the Society of Thoracic Surgeons database aided with chart review, surveys, and National Death Index data. Results The median age of patients was 53 years (43-56) in the stented group and 57 years (44-66) in the stentless group. The stented and stentless groups had high rates of heart failure (54% and 40%), liver disease (16% and 7.7%), prosthetic valve endocarditis (14% and 48%), root abscess (38% and 70%), and concomitant ascending aorta procedures (6.2% and 22%), respectively. The stentless group required permanent pacemakers in 11% of cases. Operative mortality was similar between groups (6.2% and 7.1%). The 5-year survival was 52% and 63% in the stented and stentless groups, respectively. Significant risk factors for long-term mortality included liver disease (hazard ratio, 2.38), previous myocardial infarction (hazard ratio, 1.64), congestive heart failure (hazard ratio, 1.63), and renal failure requiring dialysis (hazard ratio, 4.37). The 10-year cumulative incidence of reoperation was 12% and 3.4% for the stented and stentless groups, respectively. The 10-year freedom from reoccurrence of aortic valve endocarditis was 88% for the stented and 98% for the stentless groups. Conclusions Both stented and stentless aortic valves are appropriate conduits for replacement of active aortic valve endocarditis for select patients.

Patients with chronic renal failure (CRF) who are undergoing hemodialysis are at increased risk for infective endocarditis (IE). However, outcomes of surgical treatment for IE in these patients have not been well studied.Between 1997 and 2017, 539 patients underwent surgical treatment for IE. Of these patients, 125 were undergoing hemodialysis for end-stage renal disease (ESRD), and 414 had no history of CRF. Primary end points compared in this study were short-term survival and long-term survival.Preoperatively, dialysis-treated patients had higher incidences of diabetes (43% vs 18%), hypertension (79% vs 49%), congestive heart failure (63% vs 48%), cardiogenic shock (13% vs 5.3), and sepsis (29% vs 18%) (all P.05). Postoperatively, they experienced higher rates of prolonged mechanical ventilation (54% vs 22%), pneumonia (17% vs 5.6%), sepsis (6.4% vs 1.0%), cardiac arrest (7.2% vs 1.7%), gastrointestinal events (14% vs 5.1%), and operative mortality (14% vs 5.8%) (all P.05). The 5- and 10-year survival rates were significantly worse in the dialysis-treated group at 29% and 16%, respectively, compared with 72% and 53% in the patients who did not have CRF (P.001). ESRD was a risk factor for both short-term mortality (odds ratio, 2.0) and long-term mortality (hazard ratio, 2.7). Rates of reoperation in dialysis-treated patients were very low: 5- and 10-year incidences were 0% and 2.0%, respectively.In patients with ESRD and IE, poor postoperative outcomes emphasized the importance of prevention and raised the question whether indications for surgical treatment in the general population are appropriate for patients who are dialysis dependent. Additionally, low rates of reoperation supported the use of bioprosthetic valves in these patients.

BACKGROUND: Transcatheter aortic valve replacement (TAVR) has increased in volume as an alternative to surgical aortic valve replacement (SAVR). Comparisons of total episode expenditures, while largely ignored thus far, will be key to the value proposition for payers. METHODS: We evaluated 6,359 Blue Cross Blue Shield of Michigan and Medicare fee-for-service beneficiaries undergoing TAVR (17 hospitals, n=1,655) or SAVR (33 hospitals, n=4,704) in Michigan between 2012 and 2016. Payments through 90 post-discharge days between TAVR and SAVR were price-standardized and risk-adjusted. Centers were divided into terciles of procedural volume separately for TAVR and SAVR, and payments were compared between lowest and highest terciles. RESULTS: Payments (± standard deviation) were higher for TAVR than SAVR ($69,388 ± $22,259 vs. $66,683 ± $27,377, p

Aortoenteric fistulae are life-threatening conditions characterized by abnormal communications between the aorta and gastrointestinal tract. Aortoenteric fistulae may be characterized by the triad of bleeding, abdominal pain, or a pulsatile abdominal mass. Although hemorrhage is the most common presentation, it does not always occur; thus, patients may present with nonspecific symptoms. Computed tomography angiography findings suggestive of aortoenteric fistulae include ectopic gas within or adjacent to the aorta, discontinuity of the aortic wall, bowel wall thickening, and extravasation of contrast into the bowel. Endovascular treatments include retrograde balloon occlusion of the aorta and stent-graft deployment as well as coil, fibrin, and glue embolization of the fistulous tract. This report describes 3 cases of aortoenteric fistulae temporized and treated by interventional radiology and vascular and cardiac surgery at a single institution in an effort to increase awareness of this important clinical condition.

To improve surgical pain control through cryoablation of intercostal nerves and reduce narcotic usage in patients undergoing open thoracic or thoracoabdominal aortic aneurysm (TAA or TAAA) repair. From 2012 to 2018, 117 patients underwent open repair of TAA or TAAA. Of those patients, 25 (21%) received cryoablation (2016-2018) of their intercostal nerves and 92 (79%) did not (2012-2018). The primary outcome was pain scores and narcotic usage from extubation day 1 to 10 or the day of discharge. The median age (57 years), demographics, and preoperative comorbidities were not significantly different between the 2 groups. The cryoablation group had significantly more incidences of thoracoabdominal incisions (52% vs 28%), urgent operations (32% vs 11%), and longer duration of chest tubes compared to the noncryoablation group (all P0.05). T9-T12 intercostal arteries were selectively reimplanted. Left intercostal nerves were cryoablated from T3 to T9 if 2 thoracotomies were used; or 2 intercostal spaces above and below the thoracotomy if 1 thoracotomy was used. There were no significant differences between the noncryoablation and cryoablation groups in postoperative stroke, paraplegia (5%), pneumonia, and in-hospital mortality (0.9%). However, the average usage of narcotics was significantly reduced in the cryoablation group by 28 measured morphine equivalents (equal to four 5 mg Oxycodone)/patient/day in 10 days after extubation, P = 0.005. With cryoablation of intercostal nerves, the postoperative surgical pain was well controlled and narcotic usage was significantly decreased after TAA or TAAA repair. Cryoablation of intercostal nerves was a safe and effective measure for postoperative pain control in TAA or TAAA repair.

Background: We report the outcomes of acute type A aortic intramural hematoma (ATAAIMH) with malperfusion treated with endovascular intervention and delayed open aortic repair. Methods: Between April 1998 and April 2018, 644 patients were treated at our institution with an acute type A aortic dissection (ATAAD) or ATAAIMH, 82 (13%) had intramural hematomas (IMHs) including 12 (15%) with malperfusion syndrome (MPS) and 70 (85%) without MPS (no MPS). Data was obtained through medical record review, the Society of Thoracic Surgeons data elements, and the National Death Index database. Results: Both MPS and No MPS groups had similar comorbidities including coronary artery disease, hypertension, diabetes, and peripheral vascular disease; however, those with MPS were sicker on admission with higher rates of acute renal failure (50% vs . 1%, P

Triggering events for acute aortic dissections are incompletely understood. We sought to investigate whether there is an association between admission for acute type A aortic dissection (ATAAD) to the University of Michigan Medical Center and the reported annual influenza activity by the Michigan Department of Health and Human Services. From 1996–2019 we had 758 patients admitted for ATAAD with 3.1 admissions per month during November-March and 2.5 admissions per month during April-October (p = 0.01). Influenza reporting data by the Michigan Department of Health and Human Services became available in 2009. ATAAD admissions for the period 2009–2019 (n = 455) were 4.8 cases/month during peak influenza months compared to 3.5 cases/month during non-peak influenza months (p = 0.001). ATAAD patients admitted during influenza season had increased in-hospital mortality (11.0% vs. 5.8%, p = 0.024) and increased 30-day mortality (9.7 vs. 5.4%, p = 0.048). The results point to higher admission rates for ATAAD during months with above average influenza rates. Future studies need to investigate whether influenza virus infection affects susceptibility for aortic dissection, and whether this risk can be attenuated with the annual influenza vaccine in this patient population.

Objectives To evaluate the influence of an aortic root abscess on perioperative outcomes and long-term survival in patients with active infectious endocarditis that was treated surgically. Methods From 1996 to 2017, 336 consecutive patients were treated with aortic valve or root replacement for infective endocarditis, including patients with (n = 179) or without (n = 157) a root abscess. Data were obtained from the Society of Thoracic Surgeons data warehouse, through chart review, patient surveys, and National Death Index data. Results Demographic characteristics were similar between groups except the root abscess group had a significantly lower prevalence of congestive heart failure and higher rates of prosthetic valve endocarditis. The abscess group had significantly more aortic root replacements as well as longer cardiopulmonary bypass and crossclamp times. Operative mortality was 8.4% and 3.8% (P = .11) for the abscess and no abscess groups, respectively. Nevertheless, the root-abscess group had prolonged ventilation and longer intensive care unit stays. Kaplan-Meier survival was similar between root abscess and no abscess groups (10-year survival 41% vs 43%; P = .35). Significant risk factors for all-time mortality included age greater than 70 (hazard ratio [HR], 2.85; 95% confidence interval [CI], 1.55, 5.24), the presence of a root abscess (HR, 1.42; 95% CI, 1.02, 1.96), intravenous drug use (HR, 1.81; 95% CI, 1.13, 2.89), congestive heart failure (HR, 1.72; 95% CI, 1.22, 2.42), renal failure requiring dialysis (HR, 3.26; 95% CI, 2.30, 4.64), liver disease (HR, 3.04; 95% CI, 1.65, 5.60), and postoperative sepsis (HR, 3.00; 95% CI, 1.30, 6.93). The 10-year rate of reoperation was also similar between groups (5.9% vs 7.9%). Conclusions Thorough and extensive debridement is critical for successful treatment of active endocarditis with root abscess. Bioprosthetic stented and stentless valves are valid conduits to treat endocarditis with root abscess.

Objective: Despite the growth in thoracic aortic repair surgery, there remain concerns about the clinical and financial impact of complications secondary to these procedures. Therefore, we leveraged Medicare administrative claims to estimate the incidence, outcomes, and spending associated with complications during 90-day episodes of thoracic aortic repair surgery. Methods and Results: Using a previously validated claims-based algorithm, we identified 11,240 Medicare fee-for-service beneficiaries hospitalized for thoracic aortic repair surgery [open type A (n=4,538), open type B (n=4,091), and thoracic endovascular aortic repair procedures (TEVAR, n=2,611)] from April 2014 to March 2015. We identified any (and total number) of the following complications within 30-day of surgery: renal failure, stroke/transient ischemic attack, respiratory failure, bleeding, pneumonia, deep vein thrombosis or pulmonary embolism, surgical site infection, paralysis, or acute myocardial infarction. Overall, 5,525 patients (49.2%) developed any complication (zero complications: 50.9%, one: 28.4%, two: 13.0%, three: 5.3%, or four or more: 2.4%). For the entire sample, 90-day episode mortality was 15.4%, which was higher in patients with any complication (23.0%) compared to patients without complications (8.1%). Adjusting for patient demographics, admission status, comorbidities, and hospital random effects, the relative odds of mortality comparing patients with and without complications was 2.41 (95% CI: 2.11-2.76) (Table). On average, 90-day episode spending was $54,668±$43,287, which was also higher among patients with any complication ($69,243 vs. $40,578, p Conclusions: Complications after thoracic aortic repair were common and associated with worse outcomes and higher episode spending. Identifying and intervening upon patient and provider factors predictive of complications is essential to improving the value of thoracic aortic repair procedures.

Background The use of transcatheter aortic valve replacement (TAVR) has grown rapidly. The purpose of this study was to assess whether hospital market competition was associated with the use of TAVR. Methods We used 5 Healthcare Cost and Utilization Project state inpatient databases (Arizona, Florida, Iowa, Massachusetts, Washington) to identify patients undergoing TAVR (n = 5563) or surgical aortic valve replacement (n = 30,672) across 154 hospitals from 2011 to 2014. Using the Herfindahl-Hirschman Index (HHI) to calculate market competition, hospitals were categorized into commonly used categories of low (HHI >0.25), moderate (HHI 0.15-0.25), and high (HHI Results After adjustment, patients treated at high-competition hospitals had higher odds of receiving TAVR, relative to patients at low-competition hospitals (adjusted odds ratio [ORadj], 5.31; 95% confidence interval [CI], 2.10-13.4). TAVR use increased each year (ORadj, 1.73; 95% CI, 1.38-2.17) but was similar across HHI categories. Competition was not associated with in-hospital mortality or length of stay. Patients at high-competition hospitals were more likely to be discharged home (ORadj, 2.39; 95% CI, 1.23-4.66) compared with patients at low-competition hospitals. Conclusions Market competition was positively associated with a hospital's adoption of TAVR. Future studies should further examine the impact of competition on quality and appropriateness.

Objective The study objective was to determine if hemiarch replacement is an adequate arch management strategy for patients with acute type A aortic dissection and arch branch vessel dissection but no cerebral malperfusion. Methods From January 2008 to August 2019, 479 patients underwent open acute type A aortic dissection repair. After excluding those with aggressive arch replacement (n = 168), cerebral malperfusion syndrome (n = 34), and indeterminable arch branch vessel dissection (n = 1), 276 patients with an acute type A aortic dissection without cerebral malperfusion syndrome who underwent hemiarch replacement comprised this study. Patients were then divided into those with arch branch vessel dissection (n = 133) and those with no arch branch vessel dissection (n = 143). Results The median age of the entire cohort was 62 years, with the arch branch vessel dissection group being younger (60 vs 62 years, P = .048). Both groups had similar aortic arch and descending thoracic aortic diameters, with significantly more DeBakey type I dissections (100% vs 80%) in the arch branch vessel dissection group. The arch branch vessel dissection group had more aortic root replacement (36% vs 27%, P = .0035) and longer aortic crossclamp times (153 vs 128 minutes, P = .007). Postoperative outcomes were similar between the arch branch vessel dissection and no arch branch vessel dissection groups, including stroke (10% vs 5%, P = .12) and operative morality (7% vs 5%, P = .51). The arch branch vessel dissection group had a significantly greater cumulative incidence of reoperation (8-year: 19% vs 4%, P = .04) with a hazard ratio of 2.89 (95% confidence interval, 1.01-8.27; P = .048), which was similar between groups among only DeBakey type I dissections (8-year: 19% vs 5%, P = .11). The 8-year survival was similar between the arch branch vessel dissection and no arch branch vessel dissection groups (76% vs 74%, P = .30). Conclusions Hemiarch replacement was adequate for patients with acute type A aortic dissection with arch branch vessel dissection without cerebral malperfusion syndrome, but carried a higher risk of late reoperation.

Objective To compare the short- and long-term outcomes of unilateral and bilateral antegrade cerebral perfusion (uni-ACP and bi-ACP) in acute type A aortic dissection (ATAAD) repair. Methods From 2001 to 2017, 307 patients underwent surgical repair of an ATAAD using uni-ACP (n = 140) and bi-ACP (n = 167). Data were collected through the Department of Cardiac Surgery Data Warehouse, medical record review, and the National Death Index database. Results The demographics and preoperative comorbidities were similar between the uni-ACP and bi-ACP groups. Both groups had similar rates of procedures for aortic valve/root, ascending aorta, frozen elephant trunk, and other concomitant procedures. Perioperative outcomes were not significantly different between the 2 groups (30-day mortality: uni-ACP 3.4% vs bi-ACP 7.8%, P = .12) except reoperation for bleeding was significantly lower in uni-ACP (5% vs 12%, P = .03). Between the uni-ACP and bi-ACP groups, overall postoperative stroke rate (6% vs 9%, P = .4) and left brain stroke rate (0.7% vs 3.0%, P = .23) were not significantly different. The odds ratio of uni-ACP versus bi-ACP was 0.87 (P = .80) for postoperative stroke and 0.86 (P = .81) for operative mortality. The mid-term survival was better in the uni-ACP group, P = .027 (5-year: 84% vs 76%). The hazard ratio of all-time mortality for uni-ACP versus bi-ACP was 0.74 (95% confidence interval, 0.33-1.65), P = .46. Conclusions In ATAAD, both uni-ACP and bi-ACP are equally effective to protect the brain with low postoperative stroke rates and mortality in hemiarch to zone 3 arch replacement. Uni-ACP is recommended for its simplicity and less manipulation of arch branch vessels.

The study objective was to determine the optimal treatment for patients with acute type A aortic dissection and previous cardiac surgery.A total of 545 patients underwent open repair of an acute type A aortic dissection (July 1996 to January 2017), including patients with (n = 50) and without previous cardiac surgery (n = 495). Data were collected through the University of Michigan Cardiac Surgery Data Warehouse, medical record review, and the National Death Index database.Compared with patients without previous cardiac surgery, patients with previous cardiac surgery were older (62 vs 59 years, P = .24) and had significantly more coronary artery disease (48% vs 14%, P .001), peripheral arterial disease (24% vs 11%, P = .01), connective tissue disorders (15% vs 4.5%, P = .004), and acute renal failure on presentation (28% vs 15%, P = .02); and significantly more concomitant mitral or tricuspid procedures, longer cardiopulmonary bypass time, and more intraoperative blood transfusions. There were no statistically significant differences in postoperative major complications between previous cardiac surgery and no previous cardiac surgery groups, including stroke, myocardial infarction, new-onset dialysis, and 30-day mortality (8.9% vs 6.3%, P = .55). Multivariable logistic model showed the significant risk factors for operative mortality were cardiogenic shock (odds ratio, 9.6; P .0001) and male gender (odds ratio, 3.7; P = .006). The 5- and 10-year unadjusted survivals were significantly lower in the previous cardiac surgery group compared with the no previous cardiac surgery group (66% vs 80% and 42% vs 66%, respectively, P = .02). However, previous cardiac surgery itself was not a significant risk factor for operative mortality (odds ratio, 1.6; P = .36) or all-time mortality (hazard ratio, 1.3; P = .33).Acute type A aortic dissection in patients with previous cardiac surgery can be repaired with favorable operative mortality and long-term survival, and should be treated surgically.

Objective The study objective was to evaluate the perioperative and long-term outcomes of aortic root repair and aortic root replacement and provide evidence for root management in acute type A aortic dissection. Methods From 1996 to 2017, 491 patients underwent aortic root repair (n = 307) or aortic root replacement (n = 184) (62% bioprosthesis) for acute type A aortic dissection. Indications for aortic root replacement were intimal tear at the aortic root, root measuring 4.5 cm or more, connective tissue disease, or unrepairable aortic valvulopathy. Primary outcomes were in-hospital mortality, long-term survival, and reoperation rate for root pathology. Results Patients' median age was 61 years and 56 years in the aortic root repair group and aortic root replacement group, respectively. The aortic root replacement group had more renal failure requiring dialysis, previous cardiac intervention or surgery, heart failure, coronary malperfusion syndrome, acute myocardial infarction, and severe aortic insufficiency, as well as concomitant coronary artery bypass grafting, tricuspid valve repair, and longer cardiopulmonary bypass and aortic crossclamp times but similar arch procedures. Perioperative outcomes were similar in the aortic root repair and aortic root replacement groups, including in-hospital mortality (8.5% and 8.2%), new-onset renal failure requiring permanent dialysis, stroke, myocardial infarction, and sepsis. Kaplan–Meier 10-year survival was 62% and 65%, and the 15-year cumulative incidence of reoperation was 11% and 7% in the aortic root repair and aortic root replacement groups, respectively. The primary indication for root reoperation was aortic root aneurysm in the aortic root repair group and bioprosthetic valve deterioration in the aortic root replacement group. Conclusions Aortic root repair and aortic root replacement are appropriate surgical options for acute type A aortic dissection repair with favorable short- and long-term outcomes. Aortic root replacement should be performed for patients with acute type A aortic dissection presenting with an intimal tear at the aortic root, root aneurysm 4.5 cm or greater, connective tissue disease, or unrepairable aortic valvulopathy.

Background: Immediate open repair of acute type A aortic dissection is traditionally recommended to prevent death from aortic rupture. However, organ failure because of malperfusion syndrome (MPS) might be the most imminent life-threatening problem for a subset of patients. Methods: From 1996 to 2017, among 597 patients with acute type A aortic dissection, 135 patients with MPS were treated with upfront endovascular reperfusion (fenestration/stenting) followed by delayed open repair (OR). We compared outcomes between the first and second decades and observed mortalities with those expected with an “upfront OR for every patient” approach, determined using prognostic models from the literature (Verona, Leipzig-Halifax, Stockholm, Penn, and GERAADA [German Registry for Acute Aortic Dissection Type A] models). Results: Overall, in-hospital mortality improved between the 2 decades (21.0% versus 10.7%, P P =0.05), the risk of dying from organ failure was 6.6 times higher than dying from aortic rupture (hazard ratio=6.63; 95% CI, 1.5–29; P =0.01), and 30-day mortality after OR for MPS patients was 3.7%. Compared to the expected mortalities with the upfront OR for every patient models, our observed 30-day and in-hospital mortalities (9% and 11%, respectively) of all patients with acute type A aortic dissection were significantly lower ( P ≤0.03). Conclusions: Immediate OR is the strategy to prevent death from aortic rupture for the majority of patients with acute type A aortic dissection. However, relatively stable (no rupture, no tamponade) patients with MPS benefit from a staged approach: upfront endovascular reperfusion followed by aortic OR at resolution of organ failure.

Objective To compare perioperative and long-term outcomes in patients undergoing hemiarch and aggressive arch replacement for acute type A aortic dissection (ATAAD). Methods From 1996 to 2017, we compared outcomes of hemiarch (n = 322) versus aggressive arch replacements (zones 2 and 3 arch replacement with implantation of 2-4 arch branches, n = 150) in ATAAD. Indications for aggressive arch were arch aneurysm >4 cm or intimal tear in the aortic arch that was not resectable by hemiarch replacement, or dissection of arch branches with malperfusion. Results Patients in the aggressive arch group were significantly younger (mean age: 57 vs 61 years old) and had significantly longer hypothermic circulatory arrest, cardiopulmonary bypass, and aortic crossclamp times. There were no significant differences in perioperative outcomes between hemiarch and aggressive arch groups, including 30-day mortality (5.3% vs 7.3%, P = .38) and postoperative stroke rate (7% vs 7%, P = .96). Over 15 years, Kaplan–Meier survival was similar between hemiarch and aggressive arch groups (log-rank P = .55, 10-year survival 70% vs 72%). Given death as a competing factor, incidence rates of reoperation over 15 years (2.1% vs 2.0% per year, P = 1) and 10-year cumulative incidence of reoperation (14% vs 12%, P = .89) for arch and distal aorta pathology were similar between the 2 groups. Conclusions Both hemiarch and aggressive arch replacement are appropriate approaches for select patients with ATAAD. Aggressive arch replacement should be considered for an arch aneurysm >4 cm or an intimal tear at the arch unable to be resected by hemiarch replacement, or dissection of the arch branches with malperfusion.

Objective To assess outcomes of endovascular reperfusion followed by delayed open aortic repair for stable patients with acute type A aortic dissection and mesenteric malperfusion syndrome (mesMPS). Methods Among 602 patients with acute type A aortic dissection who presented to our center from 1996 to 2017, all 82 (14%) with mesMPS underwent upfront endovascular fenestration/stenting. Primary outcomes were in-hospital mortality and long-term survival. Patients with acute type A aortic dissection with no malperfusion syndrome of any organ (n = 419) served as controls. Results In-hospital mortality of all comers with mesMPS was 39%. After endovascular fenestration/stenting, 20 mesMPS patients (24%) died from organ failure and 11 patients (13%) died from aortic rupture before open aortic repair, 47 patients (58%) underwent aortic repair, and 4 patients (5%) survived without open repair. No patients died from aortic rupture during the second decade (2008-2017). The significant risk factors for death from organ failure after endovascular reperfusion were acute stroke (odds ratio, 23; 95% confidence interval, 4-144; P = .0008), gross bowel necrosis at laparotomy (odds ratio, 7; 95% confidence interval, 1.4-34; P = .016), and serum lactate ≥6 mmol/L (odds ratio, 13.5; 95% confidence interval, 2-97; P = .0097). There was no significant difference in operative mortality (2.1% vs 7.5%; P = .50) or long-term survival between patients with mesMPS who underwent open aortic repair after recovering from mesMPS and patients with no malperfusion syndrome. Conclusions In patients with acute type A aortic dissection with mesMPS, endovascular fenestration/stenting, and delayed open aortic repair achieved favorable short- and long-term outcomes. Surgeons should consider correcting mesenteric malperfusion before undertaking open aortic repair in patients with mesMPS, especially those with acute stroke, gross bowel necrosis at laparotomy, or serum lactate ≥6 mmol/L.

Quantifying the amount of brown adipose tissue (BAT) within white adipose tissue (WAT) in human depots may serve as a target to combat obesity. We aimed to quantify proton density fat fraction (PDFF) of BAT and WAT in relatively pure and in mixed preparation using water–fat imaging. Three ex-vivo experiments were performed at 3 T using excised interscapular BAT and inguinal/subcutaneous WAT from mice. The first two experiments consisted of BAT and WAT in separate tubes, and the third used mixed preparation with graded quantities of BAT and WAT. To investigate the influence of partial volume on PDFF metrics, low ([Formula: see text]) and high spatial resolution ([Formula: see text] acquired voxels) in two orthogonal three-dimensional sections were compared. The low-resolution acquisitions are corrected for T2* and multipeak lipid spectrum, thus considered “quantitative,” whereas the high-resolution acquisitions are not corrected but were performed to better spatially segment BAT from WAT zones. As potential BAT metrics, we quantified the average PDFF and the volume of tissue having PDFF [Formula: see text] ([Formula: see text]) based on the PDFF histogram. In the first experiment, the average PDFF of BAT was [Formula: see text] and [Formula: see text] and the average PDFF of WAT was [Formula: see text] and [Formula: see text] using high- and low-resolution techniques, respectively. A similar trend with excellent reproducibility in average PDFF of BAT and WAT was observed in the second experiment. In the third experiment over the four acquisitions, the BAT-dominant tube demonstrated lower PDFF (mean ± SD) of [Formula: see text] than WAT-dominant [Formula: see text] and WAT-only tubes [Formula: see text]. Estimating [Formula: see text] , the BAT-dominant tube demonstrated higher volume of [Formula: see text] than WAT-dominant ([Formula: see text]) and WAT-only tubes ([Formula: see text]). The presence of BAT exhibits a lower PDFF relative to WAT, thus allowing segmentation of low PDFF tissue for quantification of volume representative of BAT. Future studies will determine the clinical relevance of BAT volume within human depots.

The aim was to compare computed tomography (CT) features in acute and chronic aortic dissections (AADs and CADs) and determine if a certain combination of imaging features was reliably predictive of the acute versus chronic nature of disease in individual patients. Consecutive patients with aortic dissection and a chest CT scan were identified, and 120 CT scans corresponding to 105 patients were reviewed for a variety of imaging features. Statistical tests assessed for differences in the frequency of these features. A predictive model was created and tested on an additional 120 CT scans from 115 patients. Statistically significant features of AAD included periaortic confluent soft tissue opacity, curved dissection flap, and highly mobile dissection flap, and features of CAD included thick dissection flap, false lumen (FL) outer wall calcification, FL thrombus, dilated FL, and tear edges curling into the FL. The model predicted the chronicity of a dissection with an area under the curve of 0.98 (CI 0.98-1.00). AADs and CADs demonstrated significantly different CT imaging features.

Background Surgery in patients with Kommerell diverticulum (KD) is controversial. Although the presence of symptoms is an accepted indication, the KD itself may be a risk factor for dissection and rupture, although size criteria for operation are undefined. Methods A retrospective review of 19 adult patients who underwent surgical treatment of KD between March 2004 and June 2013 was performed. Mean age was 48 years (range, 32 to 68 years). Fifteen patients were female, 15 were symptomatic, and 13 had a right aortic arch. Sixteen patients with aberrant subclavian artery underwent a two-stage procedure involving subclavian–common carotid artery transposition or bypass followed by aortic resection, including origin of the KD, with interposition graft reconstruction. Aortic resection was performed with left heart bypass (n = 10) or deep hypothermic circulatory arrest (n = 9). Results There were no deaths or strokes. Complications after aberrant subclavian artery revascularization were transient ptosis (n = 3), graft occlusion (n = 1), recurrent laryngeal nerve injury (n = 1),phrenic nerve injury (n = 1), and reintubation (n = 1). Complications after aortic resection were intraoperative type A dissection (n = 1), phrenic nerve injury (n = 1), chylothorax (n = 1), and transient neurologic dysfunction (n = 1). Mean hospital stay after aberrant subclavian artery revascularization was 2 ± 2 days and after aortic resection, 6.4 ± 2.4 days. Of 18 available pathology specimens, all 18 showed medial degeneration. Mean follow-up was 3.3 years. Conclusions This is the largest reported single-center experience with the surgical management of KD in adults, verifying its safety and efficacy. The high percentage of KD with medial degeneration suggests asymptomatic patients with an enlarged KD also may benefit from resection.

Background— Acute coronary syndrome is the leading cause of mortality worldwide. However, treatment of acute coronary occlusion inevitably results in ischemia-reperfusion injury. Circulating natural IgM has been shown to play a significant role in mouse models of ischemia-reperfusion injury. A highly conserved self-antigen, nonmuscle myosin heavy chain II, has been identified as a target of pathogenic IgM. We hypothesized that a monoclonal antibody (m21G6) directed against nonmuscle myosin heavy chain II may inhibit IgM binding and reduce injury in a preclinical model of myocardial infarction. Thus, our objective was to evaluate the efficacy of intravenous m21G6 treatment in limiting infarct expansion, troponin release, and left ventricular dysfunction in a swine myocardial infarction model. Methods and Results— Massachusetts General Hospital miniature swine underwent occlusion of the midleft anterior descending coronary artery for 60 minutes, followed by 1 hour, 5-day, or 21-day reperfusion. Specificity and localization of m21G6 to injured myocardium were confirmed using fluorescently labeled m21G6. Treatment with m21G6 before reperfusion resulted in a 49% reduction in infarct size ( P P P Conclusions— Treatment with m21G6 significantly reduced infarct size and troponin-T release, and led to marked preservation of cardiac function in our study. Overall, these findings suggest that pathogenic IgM blockade represents a valid therapeutic strategy in mitigating myocardial ischemia-reperfusion injury.

There is no sensitive tool to monitor embolic events and predict patients at a risk for strokes during thoracic endovascular aortic repair. We examined the relationship between the number of high intensity transient signals (HITS) by transcranial doppler ultrasound and the extent of atherosclerotic plaques in aortic arch. Thirteen patients were treated as a part of a single center United States Food and Drug Administration-approved investigational device exemption for various thoracic aortic pathologies. Bilateral transcranial doppler ultrasound transducers recorded the number of HITS. CT angiography and intravascular ultrasound were used to measure the thickness of mural thrombi and determine their arch location. All 13 patients had detectable HITS, and one patient sustained a stroke. Eleven patients had quantifiable mural thrombi. The highest HITS were observed in patients with thrombi in zones 2 to 3. All three patients with bovine arch had more HITS in the right middle cerebral artery whereas the patients with normal arch anatomy had more HITS in the left middle cerebral artery. The presence of mural thrombi in zones 2 and 3, irrespective of their thickness, was associated with increased HITS during thoracic endovascular aortic repair. This is the first study to characterize the significance of mural thrombi in aortic arch and their relationship to embolic events during aortic arch manipulations.

Objective Structural changes within the aorta after thoracic endovascular aortic repair (TEVAR) for acute complicated type B thoracic aortic dissections (ABAD) remain unknown. This study reviewed and analyzed morphologic changes, volumetric data, and clinical outcomes of patients with ABAD. Methods Forty-one consecutive patients with ABAD, all with the volumetric analysis of aortic luminal changes and ≥1 year of follow-up, were treated as a part of a single-center U.S. Food and Drug Administration (FDA)-approved investigational device exemption (IDE) trial from 2002 to 2009. Indications were malperfusion in 17, rupture in 12, chest pain in 6, acute enlargement in 4, and uncontrolled hypertension in 2. Duration of symptoms was ≤14 days. Three-dimensional M2S computed tomography reconstructions (Medical MetRx Solutions, West Lebanon, NH) were analyzed for aortic volume and diameter changes, regression of the false lumen, and expansion of the true lumen. Results Emergent surgery was required in 17 (42%) patients, excluding one death at induction. Procedural success rate was 92.5%. The 30-day mortality was 4.9% for malperfusion, 4.9% for rupture, and 0% for all others, with late mortality of 0%, 9.8%, and 7.3%, respectively. Mean follow-up was 12.4 months. Permanent stroke and paraplegia rates were 4.9% (n = 2) and 0%. Ten of 12 secondary interventions were performed for 6 proximal endoleaks, 1 distal cuff endoleak, and 3 distal reperfusions. For the 33 patients without endoleaks, the true lumen volume increased by 29% at 1 month, 51% at 1 year, and 80% at 5 years. Volume regression of the false lumen was 69%, 76%, and 86%, respectively. The true lumen volume did not change at 1 month or 1 year in the endoleak group (n = 7) but increased 50% at 2 years after secondary intervention. A 10% reduction of abdominal aortic volume distal to endograft occurred over 5 years in the absence of endoleaks. Conclusions TEVAR offers a promising solution to patients with ABAD. Aortic morphologic changes occur shortly after TEVAR and remain predictable up to 5 years with continuous expansion of the true lumen and regression of the false lumen. A lack of increase in the true lumen volume is associated with endoleaks or distal reperfusion.

The transplantation of allogeneic organs triggers a massive inflammatory immune response mediated by recipient T lymphocytes recognizing donor major histocompatibility complex (MHC) molecules. Allorecognition takes place primarily in the recipient’s secondary lymphoid organs where T cells interact with intact allo-MHC molecules present on donor dendritic cells (direct allorecognition) and with donor MHC peptides processed and presented by recipient antigen presenting cells (indirect allorecognition) (1). In addition, minor histocompatibility antigens, defined as peptides derived from non-MHC donor polymorphic proteins, are presented directly or indirectly, and can trigger an alloimmune response (2). The activation of alloreactive CD4+ and CD8+ T cells triggers a cascade of events including cytotoxic T-cell differentiation, delayed type hypersensitivity (DTH) reactions, and anti-donor antibody production that lead to the rejection of allografts. On the other hand, the involvement of tissue-specific antigens in anti-graft immunity has long been postulated (3). Although some of these antigens have been identified, little is known regarding their contribution to the rejection of allografts. Recent studies in our laboratory and others’ have demonstrated that rodents receiving allogeneic heart or lung transplants mount an autoimmune response to graft tissue-specific antigens (4–6). In a mouse heart transplant model, we have reported that the T-cell response to donor MHC class I molecules is followed by an autoimmune response to cardiac myosin (CM), a contractile protein expressed by cardiomyocytes (4). CM also represents the target autoantigen in experimental autoimmune myocarditis (EAM), a mouse model of autoimmune heart disease (7). These findings suggest that anti-CM immunity may cause damage to the transplanted heart, thereby contributing to its rejection by the host. There is a report supporting this view that induction of an autoimmune response to CM in mouse recipients before transplantation accelerates the rejection of allogeneic heart transplants (4). In this case, the anti-CM autoimmune response was mediated by activated MHC class II-restricted CM-specific CD4+ TH1 cells (4). In addition, high titers of IgG1 anti-CM autoantibodies were detected in the serum of transplanted mice (4). Most importantly, tolerance induction to CM and collagen type V has been shown to significantly prolong the survival of heart and lung transplants, respectively (8, 9). Finally, several studies have provided evidence suggesting the relevance of CM autoimmunity in clinical cardiac transplantation (10–13). Collectively, these studies suggest that secondary immunity to tissue-specific antigens may represent an essential component of allograft rejection. However, the actual relevance of this phenomenon to the rejection of minor antigen-mismatched allografts in a large-animal model remains to be established. In this study, we investigated the influence of CM autoimmunity on the rejection of minor antigen-mismatched cardiac allografts performed in a swine model. We observed that the induction of an anti-CM response led to the rejection of minor antigen-mismatched cardiac allografts. The implications of these findings for the design of novel diagnostic tools and therapies in transplantation are discussed.

Objectives Brachiobasilic arteriovenous fistulas (BBAVF) can be performed in one or two stages. We compared primary failure rates, as well as primary and secondary patency rates of one- and two-stage BBAVF at two institutions. Methods Patients undergoing one- and two-stage BBAVF at two institutions were compared retrospectively with respect to age, sex, body mass index, use of preoperative venous duplex ultrasound, diabetes, hypertension, and cause of end-stage renal disease. Categorical variables were compared using chi-square and Fisher's exact test, whereas the Wilcoxon rank-sum test was used to compare continuous variables. Patency rates were assessed using the Kaplan-Meier survival analysis and the Cox proportional hazards model with propensity analysis to determine hazard ratios. Results Ninety patients (60 one-stage and 30 two-stage) were identified. Mean follow-up was 14.2 months and the mean time interval between the first and second stage was 11.2 weeks. Although no significant difference in early failure existed (one-stage, 22.9% vs two-stage, 9.1%; P = .20), the two-stage BBAVF showed significantly improved primary functional patency at 1 year at 88% vs 61% ( P = .047) (hazard ratio, 0.2 (95% confidence interval [CI], .04–.80; P = .03). Patency for one-stage BBAVF markedly decreased to 34% at 2 years compared with 88% for the two-stage procedure ( P = .047). Median primary functional patency for one-stage BBAVF was 31 weeks (interquartile range [IQR], 11–54) vs 79 weeks (IQR, 29–131 weeks) for the two-stage procedure, respectively ( P = .0015). Two-year secondary functional patency for one- and two-stage procedures were 41% and 94%, respectively ( P = .015). Conclusions Primary and secondary patency at 1 and 2 years as well as functional patency is improved with the two-stage BBAVF when compared with the one-stage procedure. Lower primary failure rates prior to dialysis with the two-stage procedure approached, but did not reach statistical significance. While reasons for these finding are unclear, certain technical aspects of the procedure may play a role.

Quantifying the amount of brown adipose tissue (BAT) within white adipose tissue (WAT) in human depots may serve as a target to combat obesity. We aimed to quantify proton density fat fraction (PDFF) of BAT and WAT in relatively pure and in mixed preparation using water-fat imaging. Three ex-vivo experiments were performed at 3 T using excised interscapular BAT and inguinal/subcutaneous WAT from mice. The first two experiments consisted of BAT and WAT in separate tubes, and the third used mixed preparation with graded quantities of BAT and WAT. To investigate the influence of partial volume on PDFF metrics, low ( 2.66 mm 3 ) and high spatial resolution ( 0.55 mm 3 acquired voxels) in two orthogonal three-dimensional sections were compared. The low-resolution acquisitions are corrected for T2* and multipeak lipid spectrum, thus considered "quantitative," whereas the high-resolution acquisitions are not corrected but were performed to better spatially segment BAT from WAT zones. As potential BAT metrics, we quantified the average PDFF and the volume of tissue having PDFF ≤ 50 % ( VOL PDFF ≤ 50 % ) based on the PDFF histogram. In the first experiment, the average PDFF of BAT was 23 ± 6 % and 21 ± 7.6 % and the average PDFF of WAT was 76 ± 7 % and 87 ± 7 % using high- and low-resolution techniques, respectively. A similar trend with excellent reproducibility in average PDFF of BAT and WAT was observed in the second experiment. In the third experiment over the four acquisitions, the BAT-dominant tube demonstrated lower PDFF (mean ± SD) of 55 ± 2 % than WAT-dominant ( 69 ± 4 % ) and WAT-only tubes ( 88 ± 4 % ) . Estimating VOL PDFF ≤ 50 % , the BAT-dominant tube demonstrated higher volume of 0.26 cm 3 than WAT-dominant ( 0.16 cm 3 ) and WAT-only tubes ( 0.01 cm 3 ). The presence of BAT exhibits a lower PDFF relative to WAT, thus allowing segmentation of low PDFF tissue for quantification of volume representative of BAT. Future studies will determine the clinical relevance of BAT volume within human depots.

Objectives Proteases of both the serine and metalloproteinase families have been shown to play a role in the pathogenesis of otitis media (OM). Inhibitors of proteases from each of these families have been shown to beneficially impact disease progression in a number of related chronic inflammatory conditions, but their use has not been studied in OM. The purpose of this study was to assess the activity of the protease inhibitors recombinant alpha 1-antitrypsin (rAAT) and ilomastat on inflammatory proteases present in human middle ear effusions (MEEs), with a view to their potential utility in the treatment of OM. Study Design Prospective and ex vivo. Methods MEEs were collected from 100 patients presenting for middle ear surgery, most commonly tympanostomy tube placement or treatment of acute posttympanostomy otorrhea (APTO). MEEs were analyzed for the presence of matrix metalloproteinases (MMPs) and human neutrophil elastase (HNE) and the inhibitory activity of rAAT and ilomastat on these proteases, respectively. Results MMP levels were highest in APTO, and HNE was highest in chronic suppurative OM and APTO. High levels of MMP and HNE (>3 mAU/min) were found in 52% and 37% of MEEs, respectively. Ilomastat and rAAT demonstrated significant inhibition of MMP and HNE activity (>30% reduction), respectively, in 80% and 82% of MEEs with high levels of activity. Conclusions Proteases are commonly found in OM. Ilomastat and rAAT are potent inhibitors of proteases in MEEs across a wide range of OM in humans. Investigation into the potential therapeutic benefits of these protease inhibitors is warranted.

In this small series, Hosoyama and colleagues 1 have described their use of negative pressure wound therapy and delayed sternal closure after resection and replacement of infected ascending aortic grafts to decrease the risk of recurrent infection. They performed daily dressing changes at the intensive care unit (ICU) bedside for 9 days, without hemorrhagic complications. All 4 patients survived, with follow-up ranging from 1 to 5 years. For 1 patient, they were evenable toeradicateCandidainfection,a difficult organism to treat in the mediastinum. The mortality from ascending aortic graft infection can be as high as 35%. Approaches to this difficult problem have led to variable success in treating the infection without significant morbidity and mortality, and more importantly, preventing recurrent infection. Antibiotic therapy alone is rarely successful without other measures to debride infected tissue. Mediastinal debridement without graft resection, followed by coverage with an omental or muscle flap, avoids the morbidity of graft replacement, but patients may need to continue lifelong, suppression antibiotic therapy for the remaining graft itself. Replacing infected Dacron graft with new Dacron or homograft may be more effective, but this is a fairly major operation, especially in older patients with multiple comorbidities, complications from sepsis, and decreased nutritional reserve. This group’s approach, of performing graft resection and replacement, using omental coverage, leaving the chest open, performing daily dressing changes in the ICU until cultures cleared, and delaying sternal closure, was aggressive but successful. The materials used are available in any hospital, and although the process is labor intensive, performing dressing changes in the ICU obviates the need for daily transport to the operating room and the use of operating room time.

We have previously shown that a short course of high-dose tacrolimus induces long-term tolerance to fully mismatched lung allografts procured from healthy MHC-inbred miniature swine. Here, we investigate whether donor brain death affects tolerance induction. Four recipient swine were transplanted with fully mismatched lung grafts from donors that were rendered brain dead and mechanically ventilated for 4 h before procurement (Group 1). These recipients were compared to two control groups (Group 2: 4 h of donor ventilation without brain death [n = 5]; and Group 3: no donor brain death with

Purpose We aim to assess the effect of regional block anesthesia on vein diameter, type of AVF placement, and fistula size and flow volume. Methods 30 patients presenting for AV access procedures were followed prospectively. Vein diameters via venous ultrasound and planned location for AV access were documented. Supraclavicular brachial plexus block was followed by repeat ultrasound and alterations in operative plan were noted. Patients returned to clinic for duplex ultrasound assessment. Results Average increase from baseline vein diameter with regional block was most pronounced in the lower cephalic (34%), upper cephalic (24.2%), and basilic veins (31.3%) and less in the brachial vein (8.7%). Type of AVF was modified following regional block in 14%. The rate of native AVF placement improved from 89% to 93% with regional block. Twenty-three AVF patients were available for follow-up (mean 24 weeks). Average fistula size was 7.9 mm (CI 6.9–8.9) and all patent fistulas developed flow volume >600 mL/min. Primary patency was attained in 83%. One thrombosis occurred after a basilic artery was lacerated during dialysis access. The average fistula increased 0.33 cm from post-block diameter (SD 0.22, PConclusions Vein diameter increases significantly in the basilic and cephalic veins following regional block anesthesia and may improve the rate of native fistula placement. Propensity to dilate after regional block anesthesia does not predict size of the fistula.

Traumatic rupture of the aorta in the rare setting of the aberrant right subclavian artery (ARSA) requires special consideration to prevent the occurrence of a devastating posterior cerebral circulation stroke. We present three cases managed by using an endovascular approach, with a discussion of important preoperative and operative issues. Three patients involved in motor vehicle collisions with multiple injuries were managed at two institutions. Computed tomography revealed transection of the aorta with incidental ARSA. All three cases were managed with a different approach. One patient did not undergo a preoperative bypass because imaging confirmed an adequate landing zone distal to the origin of the left subclavian artery. Two patients received preoperative right carotid-to-subclavian bypass for anticipated endograft coverage of both subclavian arteries to preserve single vertebral arterial flow. In one patient, an endovascular occlusion device was deployed in the ARSA before aortic endograft deployment. In the other, ARSA occlusion was performed 4 days later for a persistent type II endoleak. The patient who underwent bypass and preoperative ARSA occlusion suffered a fatal posterior circulation stroke shortly after surgery. The other two patients had no procedural complications and have not required any reinterventions at follow-up after 2 and 5 years. One patient is still undergoing rehabilitation after 5 years of follow-up for traumatic brain injury unrelated to the endograft repair. Although the incidence of ARSA is very low, preoperative imaging and assessment of cerebral blood flow are critical to prevent a perioperative stroke. Revascularization, if required to achieve a secure proximal landing zone, must be performed before endograft deployment. Bilateral subclavian revascularization is indicated if anomalies of the cerebral circulation are present.

Inadequately regulated proteolytic activity is responsible for the chronic lung tissue degeneration and irreversible loss of pulmonary function that define emphysema. In this study, we show that an inhaled broad-spectrum matrix metalloprotease inhibitor, ilomastat, can provide protection against the development of emphysema in cigarette smoke-treated mice. Control animals were exposed to daily cigarette smoke for 6 months. As has been reported previously, cigarette smoke was seen to increase significantly the recruitment of macrophages into the lungs of these animals, leading to concomitant alveolar airspace enlargement and emphysema. In animals treated daily with nebulized ilomastat for 6 months, lung macrophage levels were greatly reduced, and neutrophil accumulation was also inhibited. Corresponding reductions in airspace enlargement of up to 96% were observed. These striking observations suggest that delivery of ilomastat directly into the lungs of smoke-treated mice can not only inhibit lung tissue damage mediated by metalloproteases, but may also reduce that component of tissue degeneration mediated by excess neutrophil-derived products. Our data also suggest that the matrix metalloprotease inhibitors may represent a class of drugs that, when delivered by inhalation, could be used practically to treat cigarette smoking-related chronic obstructive pulmonary disease by modifying the course of the disease.

To the Editor: The Medical Mystery in the August 4 issue1 involved a 40-year-old man who presented with a four-day history of pain in the left upper quadrant of the abdomen, accompanied by fatigue,...