Long-term outcomes of aortic root replacement for endocarditis.

BACKGROUND: Infective endocarditis (IE) involving the aortic valve and root is associated with high risk requiring thoughtful surgical decision-making. The impact of valve and conduit choices and patient factors on long-term outcomes in this patient population is poorly documented. METHODS: From January 1976 to December 2013, 485 patients underwent aortic root and valve replacement at a single institution. Cox's proportional hazard model identified predictors of long-term survival and cumulative incidence functions were compared to assess need for reoperation with death as a competing risk. RESULTS: Median age at time of operation was 56.6 years (interquartile range: 23.1) with the indication for operation being endocarditis in 14.6% (n = 71). Stentless root replacement was used in 70% IE versus 34% non-IE (p < .001). Endocarditis at time of root replacement did not have a significant impact on survival through 15 years (IE: 37.3% vs. non-IE: 42.5%; log-rank; p = .13). After multivariable adjustment, survival was similar between patients with and without endocarditis (hazard ratio: 1.1; 95% confidence interval: [0.77, 1.62]; p = .57). Freedom from reoperation at 15 years did not vary significantly by endocarditis status (IE: 95.9% vs. non-IE: 73.6%; p = .07). Among endocarditis patients, freedom from reoperation at 10 years was similar between homograft and stentless bioprosthetic conduits (95.3% vs. 88.5%; log-rank; K-sample; p = .46). CONCLUSIONS: In a sample with frequent use of stentless prostheses, aortic root replacement for infective endocarditis had acceptable risk and long-term survival similar to root replacement for other indications. In the setting of endocarditis, root replacement with homograft or stentless bioprosthetic root has excellent durability through 15 years.

A Model for a Formal Mentorship Program in Surgical Residency.

BACKGROUND: Mentorship is a key component in preventing burnout and attrition in surgical training, yet many residencies lack a formal program, one method used to establish successful mentor relationships. We aimed to measure the difference in resident perceptions and experience after the implementation of a mentorship program. METHODS: An anonymous survey was distributed to all general surgery residents at a single academic institution before and after implementation of a year-long mentorship program that involved assigned mentors, two social events, and recommended mentorship meetings. Responses were recorded on a five-point Likert scale. RESULTS: Half of respondents (n = 17, 53%) attended at least one event, and 66% (n = 21) had at least one mentor meeting. The proportion of residents who identified a faculty mentor increased from 59% to 75%. Residents with two or more mentor meetings (n = 12, 38%) were more likely to report faculty were interested in mentoring and cared about their development (3.5 versus 4.6, 3.6 versus 4.6, P < 0.001). They were more likely to identify faculty approachable for resident performance (3.8 versus 4.6, P < 0.02) and outside of work concerns (3.2 versus 4.3, P < 0.01) and were more likely to be satisfied with the amount of mentorship received (2.8 versus 4.0 P < 0.001). CONCLUSIONS: Implementation of a formal mentorship program resulted in an improvement in resident perception of faculty involvement and support. Meeting with a mentor resulted in a significant improvement in resident perception. Implementation of a mentorship program can improve resident experience, and few interactions are needed to affect the change.

Selective Sinus Replacement for Aortic Root Aneurysm: Durable Approach in Selected Patients.

BACKGROUND: Selective sinus replacement (SSR) allows a tailored repair approach in patients with sinus of Valsalva or asymmetric aortic root aneurysm. SSR avoids the need for coronary reimplantation for nondiseased sinuses and shortens operative time, although potential for late growth of retained sinuses exists. This study describes selection of patients and assesses operative outcomes and late root dimensions after SSR. METHODS: From 2006 to 2020, 60 patients underwent SSR at a single referral institution. Mixed effect models were used to assess trajectory of postoperative growth of remaining sinuses, adjusting for age of the patient, valve morphology, and baseline root diameter. RESULTS: Median age of the patients was 57 (interquartile range [IQR], 48-65) years. Twenty-four (40%) had a bicuspid aortic valve. Most patients (n = 55 [92%]) underwent single sinus replacement (n = 46 noncoronary, n = 9 right), whereas 5 (8%) underwent repair of both the right and noncoronary sinuses. Concomitant aortic valve replacement was performed in 15 patients (25%); aortic valve repair with internal ring annuloplasty or cusp plication was performed in 37 (62%). There was no operative death, stroke, renal failure, or respiratory failure. Median preoperative root diameter was 53 mm (IQR, 51-56 mm) vs 42 mm (IQR, 39-45 mm) at median imaging follow-up of 34 (IQR, 13-49) months. Rate of midterm root growth was 0.2 mm/y, and there were no late root reinterventions. CONCLUSIONS: For patients with sinus of Valsalva or asymmetric root aneurysm, SSR is associated with excellent operative outcomes, and midterm follow-up suggests that the technique is durable. Longer term follow-up is needed to confirm continued stability of the aortic root.

Tailored approach and outcomes of aortic arch reconstruction after acute type A dissection repair.

OBJECTIVE: After limited root/ascending with or without hemiarch repair for acute type A aortic dissection (ATAAD), 20% to 30% of patients require distal reintervention, frequently for arch pathology. In this report, we describe an institutional algorithm for arch management after previous limited ATAAD repair and detail operative and long-term outcomes. METHODS: From August 2005 to April 2021, 71 patients status post previous limited ATAAD repair underwent reoperative arch repair involving zones 1 to 3 for aneurysmal degeneration of residual arch dissection including complete cervical debranching with zone 0/1 thoracic endovascular aortic repair in 6 (8%), open total arch in 13 (18%), type I hybrid arch repair in 23 (32%), and type II/III hybrid arch repair in 29 (41%). RESULTS: Mean age was 59 ± 12 years; time from index ATAAD repair to reoperation was 4 (interquartile range, 2-9) years. There were 2 (2.8%) in-hospital deaths and 2 (2.8%) postdischarge deaths within 30 days of surgery. Three patients suffered stroke (4.2%) and 2 (2.8%) had acute renal failure requiring dialysis. Overall Kaplan-Meier survival was 78%, 70%, and 58% at 1, 3, and 5 years, respectively. Institutional experience appeared to play a significant role in early and late outcomes, because there have been no operative mortalities in the past 9 years and improved survival of 87% versus 66%, 79% versus 58%, and 79% versus 40% at 1, 3, and 5 years in comparisons of the past 9 years with the previous era (P = .01). CONCLUSIONS: Aneurysmal degeneration of residual arch dissection after limited ATAAD repair presents a complex reoperative challenge. An algorithmic operative approach tailored to patient anatomy and comorbidities yields excellent early and late outcomes, which continue to improve with increasing institutional experience.

Stent Graft-induced Aortic Wall Injury: Incidence, Risk Factors, and Outcomes.

BACKGROUND: Stent graft-induced new entry has been described in thoracic endovascular aortic repair for aortic dissection. The incidence of stent graft-induced aortic wall injury (SAWI) related to iatrogenic injury in nondissections is incompletely described. We describe incidence, risk factors, and outcomes of SAWI. METHODS: All post-thoracic endovascular aortic repair computed tomography angiograms (January 2005 to December 2018) were reviewed for radiographic evidence of SAWI. Endograft-induced aortic dissections were likewise considered SAWI. Patient characteristics, time to SAWI, and need for reintervention were noted. Cox proportional hazards modeling was used to identify risk factors for SAWI. RESULTS: Within the study cohort (n = 430), 38 patients (9%) had SAWI during a median follow-up of 2.3 years (interquartile range, 4.8); 42% (n = 16) were proximal, 53% (n = 20) distal, and 5% (n = 2) both proximal and distal. Nine (23%) were distal intimal flap injuries in dissection cases, thus subclassifying them as stent graft-induced new entry. Twenty-nine percent of SAWI (n = 11) required reintervention. Of these, 45% (n = 5) were open, and 55% (n = 6) were endovascular. Thoracic endovascular aortic repair for acute dissection had a higher incidence of SAWI development (hazard ratio 4.6; 95% confidence interval, 2.4 to 9; P < .001) as compared with other indications. Use of devices with proximal bare springs or barbs was also associated with increased SAWI incidence (hazard ratio 5.3; 95% confidence interval, 2.6 to 11.0; P < .001). CONCLUSIONS: The rate of SAWI after thoracic endovascular aortic repair is low (9%), but nearly one third will require reintervention. Thoracic endovascular aortic repair in the setting of acute dissection and use of devices with proximal bare springs or barbs were associated with an increased incidence of SAWI.

Coronary Anastomosis Simulation: Directed Interventions to Optimize Success.

BACKGROUND: The role of simulation-based training in coronary artery bypass grafting remains undefined. Barriers to simulator use include clinical and personal obligations, insufficient materials, and lack of mentorship. The purpose of this study was to implement a longitudinal, residency-wide coronary anastomosis simulation curriculum. METHODS: A prospective observational study was conducted from 2018 to 2019 at a single academic center. All residents of the Thoracic Surgery training program participated. Each participant was provided a low-fidelity coronary anastomosis simulator, high-quality instruments, and faculty mentor. Formal assessments were held quarterly, and residents were encouraged to practice alone and with their mentor. Baseline and follow-up metrics were compared with simple descriptive statistics. RESULTS: Seventeen residents and 12 faculty participated in the study. Residents demonstrated increased use of the simulator, with 21% participating in independent practice at baseline and 82% in the fourth quarter (P = .02). The median score on the Thoracic Surgery Directors Association Vessel Anastomosis Assessment improved from 42 out of 65 at baseline to 54 out of 65 in the fourth quarter (P = .04), and mean anastomosis time was reduced by 5 minutes 6 seconds (P = .02). Over 12 months, junior residents demonstrated a mean reduction in anastomosis time of 6 minutes 36 seconds, and senior residents decreased anastomosis time by 3 minutes 6 seconds (P = .02). CONCLUSIONS: Providing residents with a low-fidelity coronary anastomosis trainer with high-quality instruments and a faculty mentor improved rates of independent practice, Thoracic Surgery Directors Association assessment scores, and anastomosis time. Our next step is validating the coronary simulator curriculum by measuring improvement of resident performance in the operating room.

Emerging trends in mediastinitis: National Veterans Health Administration experience with methicillin-resistant Staphylococcus aureus prevention.

OBJECTIVES: Perioperative bacterial decolonization and prophylactic antibiotic therapy at the Veterans Affairs Health Care System have changed over the past decade. Our objectives were to identify associated changes in the microbiology of mediastinitis and to perform a contemporary survival analysis in patients with mediastinitis after isolated coronary artery bypass grafting procedure. METHODS: From January 2006 to December 2015, 45,323 consecutive patients underwent coronary artery bypass grafting at 83 medical centers. The Veterans Affairs Health Care System nationwide administrative database was queried to identify patients with postoperative mediastinitis and obtain patient-level data. Simple descriptive statistics and multivariable logistic regression were used to analyze microbiologic data and identify risk factors for infection. Poisson regression was used to determine yearly incidence estimates. Cox proportional hazard model identified predictors of long-term survival from date of operation. RESULTS: During the study period, 348 patients (0.78%) developed postoperative mediastinitis-with a stable rate of incidence (Cochrane-Armitage test, P = .69). Of patients with microbiologic data, 75.5% of infections (n = 188) were caused by gram-positive and 24.5% (n = 61) gram-negative organisms. The incidence of methicillin-resistant Staphylococcus aureus mediastinitis decreased during the study period (Cochrane-Armitage test, P = .013). Gram-negative mediastinitis occurred earlier than gram-positive mediastinitis (median, 15.0 vs 25.0 days; P < .0001). Patients with mediastinitis did not have increased 30-day mortality (2.0% vs 1.9%; P = .9), but had worse long-term survival compared with uninfected patients (P < .0001). CONCLUSIONS: The incidence of methicillin-resistant S aureus mediastinitis has decreased over the past decade. Gram-negative bacteria are responsible for 1 in 4 cases of mediastinitis and infection is diagnosed earlier in the postoperative period than gram-positive mediastinitis. These findings highlight the need for efforts to prevent gram-negative and methicillin-susceptible S aureus mediastinitis.

Early outcomes with durable left ventricular assist device replacement using the HeartMate 3.

BACKGROUND: The HeartMate 3 (HM3) left ventricular assist device (LVAD) (Abbott, Inc, Chicago, Ill) is a fully magnetically levitated centrifugal implantable pump used to treat patients with chronic heart failure. The MOMENTUM (Multicenter Study of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy With HeartMate 3) trial demonstrated that patients treated with the HM3 experienced reduced need for reoperation for LVAD replacement compared with a control group receiving an axial flow design, Heartmate II (Abbott, Inc). However, there are few reports of using HM3 as the replacement pump in patients who already are supported by a durable LVAD and experience a device-related complication necessitating replacement. METHODS: An institutional LVAD database was used to identify 19 consecutive patients who underwent pump replacement to HM3 (group 1) versus 85 consecutive control patients who underwent pump replacement to either Heartmate II or HeartWare Ventricular Assist Device (Medtronic Inc, Minneapolis, Minn) (group 2), at a single institution from January 2010 to August 2018. Patient baseline characteristic and outcomes were obtained from a prospectively maintained database. The primary endpoint was a composite of freedom from death or need for another replacement surgery. RESULTS: There was no difference between the groups in heart failure etiology, indication for replacement, as well as the average days on the previous pump or the type of previous pump. The HM3 group did have a significantly greater body mass index (37 vs 31.6 P = .01), a greater number of previous LVAD implants (36.8% vs 5.9%, had 2 previous LVADs, P < .001), and a greater number of previous sternotomies (31.6% vs 7.1%, had 3 previous sternotomies, P = .001). No difference was found between the groups in terms of postoperative adverse event rates. With regards to the primary endpoint, the patients with HM3 replacements (group 1) versus group 2 experienced significantly greater freedom from either death or need for another replacement during the follow-up period (P = .039). During follow-up, there were no thrombosis events for the patients who received replacement with HM3. CONCLUSIONS: LVAD replacement with HM3 can be performed safely and may be considered as the pump of choice in patients requiring LVAD replacement.

Constrictive Pericarditis After Lung Transplantation.

BACKGROUND: Constrictive pericarditis is a rare, but increasingly recognized long-term postoperative complication of lung transplantation. Heightened clinical suspicion, improved diagnostic imaging, and effective surgical treatment of the disease have led to progressive awareness of the pathology. We present our institutional experience with constrictive pericarditis after lung transplant in an effort to investigate the cause and natural history of the disease. METHODS: From October 2005 to October 2018, 1234 patients underwent orthotopic lung transplantation at Duke University Hospital. An institutional database was queried to identify incident patients and determine baseline clinical data. At a median of 11.2 months (interquartile range = 4.6-28.6 mo), 10 patients (0.8%) developed constrictive pericarditis. Simple descriptive statistics were used to describe cohort characteristics and identify variables associated with constrictive pericarditis after lung transplantation. RESULTS: The indication for transplantation at index operation was idiopathic pulmonary fibrosis in 8 of 10 patients (1.2% of the 760 restrictive lung disease patients transplanted in the same time period). All 10 patients presented with worsening dyspnea and pleural effusions. Right heart catheterization confirmed constrictive physiology in all cases. Eight patients underwent pericardiectomy with improvement in cardiovascular hemodynamics and resolution of symptoms with no 30-day mortality. CONCLUSIONS: Diagnosis of constrictive pericarditis should be considered in patients with new-onset heart failure symptoms or recurrent pleural effusions within 2 years of lung transplantation. Idiopathic pulmonary fibrosis may be associated with increased risk for constrictive pericarditis. Pericardiectomy is a safe and effective treatment for posttransplant constrictive pericarditis.

Minimally Invasive Pulmonary Fibroelastoma Resection.

Pulmonary fibroelastomas are a rare primary cardiac tumor with less than 50 cases reported in the literature to date. We performed a minimally invasive valve-sparing tumor resection through a left anterior mini-incision (LAMI). The procedure was performed without cardiac arrest or aortic cross clamp, expediting postoperative recovery and allowing for an uncomplicated discharge on postoperative day 5. LAMI is a safe and reliable alternative to median sternotomy for patients requiring interventions on the right ventricular outflow tract and main pulmonary artery, including pulmonary fibroelastoma resection and pulmonary valve replacement when needed.

Machine-learning phenotypic classification of bicuspid aortopathy.

BACKGROUND: Bicuspid aortic valves (BAV) are associated with incompletely characterized aortopathy. Our objectives were to identify distinct patterns of aortopathy using machine-learning methods and characterize their association with valve morphology and patient characteristics. METHODS: We analyzed preoperative 3-dimensional computed tomography reconstructions for 656 patients with BAV undergoing ascending aorta surgery between January 2002 and January 2014. Unsupervised partitioning around medoids was used to cluster aortic dimensions. Group differences were identified using polytomous random forest analysis. RESULTS: Three distinct aneurysm phenotypes were identified: root (n = 83; 13%), with predominant dilatation at sinuses of Valsalva; ascending (n = 364; 55%), with supracoronary enlargement rarely extending past the brachiocephalic artery; and arch (n = 209; 32%), with aortic arch dilatation. The arch phenotype had the greatest association with right-noncoronary cusp fusion: 29%, versus 13% for ascending and 15% for root phenotypes (P < .0001). Severe valve regurgitation was most prevalent in root phenotype (57%), followed by ascending (34%) and arch phenotypes (25%; P < .0001). Aortic stenosis was most prevalent in arch phenotype (62%), followed by ascending (50%) and root phenotypes (28%; P < .0001). Patient age increased as the extent of aneurysm became more distal (root, 49 years; ascending, 53 years; arch, 57 years; P < .0001), and root phenotype was associated with greater male predominance compared with ascending and arch phenotypes (94%, 76%, and 70%, respectively; P < .0001). Phenotypes were visually recognizable with 94% accuracy. CONCLUSIONS: Three distinct phenotypes of bicuspid valve-associated aortopathy were identified using machine-learning methodology. Patient characteristics and valvular dysfunction vary by phenotype, suggesting that the location of aortic pathology may be related to the underlying pathophysiology of this disease.

Outcomes After Operations for Unicuspid Aortic Valve With or Without Ascending Repair in Adults.

BACKGROUND: Unicuspid aortic valve is an important subset of bicuspid aortic valve, and knowledge regarding its aortopathy pattern and surgical outcomes is limited. Our objectives were to characterize unicuspid aortic valve patients, associated aortopathy, and surgical outcomes. METHODS: From January 1990 to May 2013, 149 adult unicuspid aortic valve patients underwent aortic valve replacement or repair for aortic stenosis (n = 13), regurgitation (n = 13), or both (n = 123), and in 91 (61%) the aortic valve operation was combined with aortic repair. Data were obtained from the Cardiovascular Information Registry and medical record review. Three-dimensional imaging analysis was performed from preoperative computed tomography and magnetic resonance imaging scans. The Kaplan-Meier method was used for survival analysis. RESULTS: Patients had a mean maximum aortic diameter of 44 ± 8 mm and variably involved the aortic root, ascending, or arch, or both. Patients with valve operations alone were more likely to be hypertensive (p = 0.01) and to have severe aortic stenosis (p = 0.07) than those who underwent concurrent aortic operations. There were no operative deaths, strokes, or myocardial infarctions. Patients undergoing aortic repair had better long-term survival. Estimated survival at 1, 5, and 10 years was 100%, 100%, and 100% after combined operations and was 100%, 88%, and 88% after valve operations alone (p = 0.01). CONCLUSIONS: Patients with a dysfunctional unicuspid aortic valve frequently present with an ascending aneurysm that requires repair. Combined aortic valve operations and aortic repair was associated with significantly better long-term survival than a valve operation alone. Further study of this association may direct decisions about timing of surgical intervention.