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The SherpaPak Cardiac Transport System is a novel technology that provides stable, optimal hypothermic control during organ transport. The objectives of this study were to describe our experience using the SherpaPak system and to compare outcomes after heart transplantation after using SherpaPak versus the conventional static cold storage method (non-SherpaPak).From 2018 to June 2021, 62 SherpaPak and 186 non-SherpaPak patients underwent primary heart transplantation at Stanford University with follow-up through May 2022. The primary end point was all-cause mortality, and secondary end points were postoperative complications. Optimal variable ratio matching, cox proportional hazards regression model, and Kaplan-Meier survival analyses were performed.Before matching, the SherpaPak versus non-SherpaPak patients were older and received organs with significantly longer total allograft ischemic time. After matching, SherpaPak patients required fewer units of blood product for perioperative transfusion compared with non-SherpaPak patients but otherwise had similar postoperative outcomes such as hospital length of stay, primary graft dysfunction, inotrope score, mechanical circulatory support use, cerebral vascular accident, myocardial infarction, respiratory failure, new renal failure requiring dialysis, postoperative bleeding or tamponade requiring reoperation, infection, and survival.In conclusion, this is one of the first retrospective comparison studies that evaluated the outcomes of heart transplantation using organs preserved and transported via the SherpaPak system. Given the excellent outcomes, despite prolonged total allograft ischemic time, it may be reasonable to adopt the SherpaPak system to accept organs from a remote location to further expand the donor pool.

The objective of this work was to delineate career progression and research productivity of women practicing cardiothoracic surgery in the academic setting.Cardiothoracic surgeons at the 79 accredited US cardiothoracic surgery training programs in 2020 were included in this cross-sectional analysis. Data regarding subspecialization, training, practice history, and publications were gathered from public sources including department websites, CTSNet, and Scopus.A total of 1065 surgeons (51.3% cardiac, 32.1% thoracic, 16.6% congenital) were identified. Women accounted for 10.6% (113) of the population (7.9% of cardiac, 15.5% of thoracic, 9.6% of congenital surgeons). The median number of cardiothoracic surgeons per institution was 12 (interquartile range [IQR], 10-17), with a median of 1 woman (IQR, 0-2). Fifteen of 79 programs (19%) had no women. Among women faculty 5.3% were clinical instructors, 51.3% were assistant professors, 23.0% were associate professors, 16.8% were full professors, and 3.5% had unspecified titles (vs 2.0%, 32.9%, 23.0%, 37.5%, and 4.6% among men, respectively; P.001). Women and men authored a comparable number of first-author (0.4 [IQR, 0.0-1.3] vs 0.5 [IQR, 0.0-1.1], P = .56) publications per year but fewer last-author (0.1 [IQR, 0.0-0.7] vs 0.4 [IQR, 0.0-1.3], P.0001) and total publications per year (2.7 [IQR, 1.0-6.2] vs 3.7 [IQR, 1.3-7.8], P = .05) than men. The H-index was lower for women than for men overall (8.0 [IQR, 3.0-15.0] vs 15.0 [IQR, 7.0-28.0], P.001) but was similar between men and women who had been practicing for 10 to 20 years.Gender disparities persist in academic cardiothoracic surgery. Efforts should be made to support women in achieving senior roles and academic productivity.

INTRODUCTION: There is growing concern regarding the attrition of surgeon-scientists. To understand the decline of basic science research (BSR), it is essential to examine trends in research conducted by trainees. We hypothesized that, over recent decades, cardiothoracic (CT) surgery trainees have published fewer BSR articles. MATERIALS AND METHODS: CT surgeons at United States training institutions in 2020 who completed training in the past three decades, excluding international trainees, were analyzed (1991–2000: n = 148; 2001–2010: n = 228; 2011–2020: n = 247). Publication records were obtained from Scopus. Articles with medical subject heading terms involving molecular/cellular or animal research were classified as BSR using the National Institutes of Health iCite Translation module. Data were analyzed using Fisher’s exact test or the Wilcoxon rank-sum test. RESULTS: While the proportion of surgeons who published a first-author paper during training remained stable over the past two decades (178/228 [78.1%] versus 189/247 [76.5%], P = 0.7427), the proportion who published a first-author BSR paper decreased significantly (135/228 [59.2%] versus 96/247 [38.9%], P < 0.0001). Among surgeons who published a first-author paper in training, the total papers published by each trainee did not change over the past two decades (3.5 versus 3.3 first-author papers per 10 y of training, P = 0.8819). However, the number of BSR papers published during training decreased significantly (1.7 versus 0.8 first-author papers per 10 y of training, P < 0.0001). CONCLUSIONS: CT surgery trainees are publishing fewer BSR papers. Additional efforts are needed to increase exposure of trainees to BSR and reaffirm that BSR is a valuable and worthwhile pursuit for academic surgeons.

The National Institutes of Health (NIH) recently developed the relative citation ratio (RCR), calculated as article citations benchmarked to NIH-funded publications in the same field. Here, we characterized the scholarly impact of academic cardiothoracic (CT) surgeons and their research using the RCR.Using a database of 992 CT surgeons, we calculated the RCR for all articles published by each surgeon since 1980 using the NIH iCite database. All data were collected from publicly available online sources. Data are presented as median (interquartile range) or as odds ratios (ORs) for multivariable logistic regression analysis.Where RCR 1.00 indicates equal impact as an NIH-funded publication, the RCR among all 37,402 CT surgery articles was 0.84 (0.33-1.83) and the RCR among NIH-funded CT surgery articles was 1.07 (0.53-2.17). CT surgeons exhibited a career median RCR of 0.82 (0.54-1.13) and maximum RCR of 6.20 (3.04-13.57). Predictors of career median RCR1.00 included female gender (OR 2.23, P = 0.001), thoracic subspecialization (OR 2.50, P 0.001), full professor rank (OR 1.89, P = 0.001), and NIH funding (OR 1.75, P = 0.001). Predictors of career maximum RCR50th percentile among CT surgeons included male gender (OR 1.87, P = 0.030), thoracic subspecialization (OR 2.05, P 0.001), full professor rank (OR 4.89, P 0.001), NIH funding (OR 3.17, P 0.001), and career duration (OR 1.03, P = 0.002).We present the first assessment of the NIH-validated RCR for academic CT surgery. CT surgery research is highly impactful, although gender disparities persist with respect to the highest-impact research of our specialty.

OBJECTIVE Advanced clinical fellowship training has become a popular option for surgical trainees seeking to bolster their clinical training and expertise. However, the long-term academic impact of this additional training following a traditional thoracic surgery fellowship is unknown. This study aimed to delineate the impact of an advanced clinical fellowship on subsequent research productivity and advancement in academic career among general thoracic surgeons. METHODS Using an internally constructed database of active, academic general thoracic surgeons who are current faculty at accredited cardiothoracic surgery training programs within the United States, surgeons were dichotomized according to whether an advanced clinical fellowship was completed or not. Academic career metrics measured by research productivity, scholarly impact (H-index), funding by the National Institutes of Health, and academic rank were compared. RESULTS Among 285 general thoracic surgeons, 89 (31.2%) underwent an advanced fellowship, whereas 196 (68.8%) did not complete an advanced fellowship. The most commonly pursued advanced fellowship was minimally invasive thoracic surgery (32.0%). There were no differences between the two groups in terms of gender, international medical training, or postgraduate education. Those who completed an advanced clinical fellowship were less likely to have completed a dedicated research fellowship compared to those who had not completed any additional clinical training (58.4% vs. 74.0%, p = 0.0124). Surgeons completing an advanced clinical fellowship demonstrated similar cumulative first-author publications (p = 0.4572), last-author publications (p = 0.7855), H-index (p = 0.9651), National Institutes of Health funding (p = 0.7540), and years needed to advance to associate professor (p = 0.3410) or full rank professor (p = 0.1545) compared to surgeons who did not complete an advanced fellowship. These findings persisted in sub-analyses controlling for surgeons completing a dedicated research fellowship. CONCLUSIONS Academic general thoracic surgeons completing an advanced clinical fellowship demonstrate similar research output and ascend the academic ladder at a similar pace as those not pursuing additional training.

Surgeons are traditionally categorized as working either in academic or private/community practice, but some transition between the two environments. Here, we profile current academic cardiothoracic surgeons who began their attending careers in private or community practice. We hypothesized that research activity may distinguish cardiothoracic surgeons who started in non-academic versus academic practice.Publicly available data regarding professional history and research productivity were collected for 992 academic cardiothoracic surgeons on faculty at the 77 cardiothoracic surgery training programs in the United States in 2018. Data are presented as medians analyzed with the Mann-Whitney test or proportions analyzed with Fisher exact test or the χA total of 80 (8.1%) academic cardiothoracic surgery faculty started their careers in non-academic practice, and 912 (91.9%) started directly in academia. Those who started in non-academic practice spent a median 7.0 y in private/community practice and were more likely to be cardiac surgeons (68.8% vs 51.6%, P = .0132). They were equally likely to pursue a protected research fellowship (56.3% vs 57.0%, P = .9067) and publish research during training (92.5% vs 91.1%, P = .8374), but they published fewer total papers by the end of cardiothoracic surgery fellowship (3.0 vs 7.0, P = .0001) and fewer papers per year as an academic attending (0.8 vs 2.9, P.0001). Nevertheless, the majority of cardiothoracic surgery faculty who started in non-academic practice are currently active in research (68.8%), and 2 such surgeons received National Institutes of Health R01 funding.Transitioning from non-academic to academic practice is an uncommon but feasible pathway for interested cardiothoracic surgeons.

There is increasing concern regarding the attrition of surgeon-scientists in cardiothoracic (CT) surgery. However, the characteristics of CT surgeons who are actively leading basic science research (BSR) have not been examined. We hypothesized that early exposure to BSR during training and active grant funding are important factors that facilitate the pursuit of BSR among practicing CT surgeons.We created a database of 992 CT surgeons listed as faculty at accredited United States CT surgery teaching hospitals in 2018. Data regarding each surgeon's training/professional history, publication record, and National Institutes of Health funding were acquired from publicly available online sources. Surgeons who published at least one first- or last-author paper in 2017-2018 were considered to be active, lead researchers.Of the 992 CT surgeons, 73 (7.4%) were actively leading BSR, and 599 (60.4%) were actively leading only non-BSR. Only 2 women were actively leading BSR. Surgeons actively leading BSR were more likely to have earned a PhD degree (20.5% versus 9.7%, P = 0.0049), and more likely to have published a first-author BSR paper during training (76.7% versus 40.9%, P0.0001). Surgeons actively leading BSR were also more likely to have an active National Institutes of Health grant (34.2% versus 5.8%, P0.0001), especially an R01 grant (21.9% versus 2.5%, P0.0001).A small minority of CT surgeons at academic training hospitals are actively leading BSR. In order to facilitate the development of surgeon-scientists, additional support must be given to trainees and junior faculty, especially women, to enable early engagement in BSR.

BACKGROUND Early engagement in cardiothoracic (CT) surgery research may help attract trainees to academic CT surgery, but whether this early exposure boosts career-long academic achievement remains unknown. METHODS A database of all CT surgery faculty at accredited, academic CT surgery training programs in the United States during the year 2018 was established. Excluding international medical graduates, surgeons who started general surgery residency in the United States before 2004 and who published at least 1 manuscript before traditional CT fellowship training were included (n = 472). Each surgeon's educational background, work history, and research publications were recorded from publicly available online sources. RESULTS Before fellowship training, 370 surgeons (78.4%) coauthored a CT surgery manuscript, and 102 (21.6%) published only on subjects unrelated to CT surgery. Regardless of whether surgeons pursued dedicated research training or not, those who coauthored a CT surgery manuscript before fellowship training published more papers per year as an attending (P < .01), resulting in more total publications (P < .01) and a higher H-index (P < .01) over comparably long careers. Among CT surgeons who did not publish CT surgery research before fellowship training, those who coauthored a CT surgery manuscript during fellowship also exhibited enhanced future academic productivity. CONCLUSIONS Academic CT surgeons who published CT surgery research before fellowship training ultimately exhibited more prolific and impactful research profiles compared with those who published only on subjects unrelated to CT surgery during training. Efforts to increase early engagement in CT surgery research among trainees should be fully endorsed.

Aims Since 1968, heart transplantation has become the definitive treatment for patients with end-stage heart failure. We aimed to summarize our experience in heart transplantation at Stanford University since the first transplantation performed over 50 years ago. Methods and results From 6 January 1968 to 30 November 2020, 2671 patients presented to Stanford University for heart transplantation, of which 1958 were adult heart transplantations. Descriptive analyses were performed for patients in 1968–95 (n = 639). Stabilized inverse probability weighting was applied to compare patients in 1996–2006 (n = 356) vs. 2007–19 (n = 515). Follow-up data were updated through 2020. The primary endpoint was all-cause mortality. Prior to weighting, recipients in 2007–19 vs. those in 1996–2006 were older and had heavier burden of chronic diseases. After the application of stabilized inverse probability weighting, the distance organ travelled increased from 84.2 ± 111.1 miles to 159.3 ± 169.9 miles from 1996–2006 to 2007–19. Total allograft ischaemia time also increased over time (199.6 ± 52.7 vs. 225.3 ± 50.0 min). Patients in 2007–19 showed superior survival than those in 1996–2006 with a median survival of 12.1 vs. 11.1 years. Conclusion In this half-century retrospective descriptive study from one of the largest heart transplant programmes in the USA, long-term survival after heart transplantation has improved over time despite increased recipient and donor age, worsening comorbidities, increased technical complexity, and prolonged total allograft ischaemia time. Further investigation is warranted to delineate factors associated with the excellent outcomes observed in this study.

Background Women remain underrepresented in cardiothoracic surgery (CTS). In 2005, Women in Thoracic Surgery (WTS) began offering scholarships to promote engagement of women in CTS careers. This study explores the effect of WTS scholarships on CTS career milestones. Methods We assessed career development using the number of awardees matching into CTS residency/fellowship, American Board of Thoracic Surgery (ABTS) certification, and academic CTS appointment. Scholarship awardee data were obtained from our WTS database. Comparison data were gathered from the National Residency Match Program and ABTS. Details of the current roles of ABTS-certified women were determined from public resources. Qualitative results were gathered from post-scholarship surveys. Results A total of 106 WTS scholarships have been awarded to 38 medical students (36%), 41 general surgery residents (39%), and 27 CTS residents/fellows (25%). Among medical students, 26% of awardees entered integrated CTS residency (vs Conclusions Receipt of a WTS scholarship is associated with successful pursuit of CTS career milestones at significantly higher rates than contemporaries. These scholarships foster a supportive community for women trainees in CTS.

Introduction: Central venous catheters (CVCs) are often trimmed during heart transplantation and pediatric cardiac surgery. However, the risk of endothelial injury caused by the cut tip of the CVC has not been evaluated. We hypothesized that there is no difference in the degree of endothelial injury associated with trimmed CVCs versus standard untrimmed CVCs. Methods: In four adult male sheep, the left external jugular vein was exposed in three segments, one designated for an untouched control group, one for the trimmed CVC group, and one for the untrimmed CVC group. Trimmed and untrimmed CVC tips were rotated circumferentially within their respective segments to abrade the lumen of the vein. The vein samples were explanted, and two representative sections from each sample were analyzed using hematoxylin and eosin (H&E) staining, as well as with immunohistochemistry against CD31, von Willebrand factor (vWF), endothelial nitric oxide synthase (eNOS), and caveolin. Higher immunohistochemical stain distributions and intensities are associated with normal health and function of the venous endothelium. Data are presented as counts with percentages or as means with standard error. Results: H&E staining revealed no evidence of endothelial injury in 6/8 (75%) samples from the untouched control group, and no injury in 4/8 (50%) samples from both the trimmed and untrimmed CVC groups ( p = 0.504). In all remaining samples from each group, only mild endothelial injury was observed. Immunohistochemical analysis comparing trimmed CVCs versus untrimmed CVCs revealed no difference in the percentage of endothelial cells staining positive for CD31 (57.5% ± 7.2% vs 55.0% ± 9.2%, p = 0.982), vWF (73.8% ± 8.0% vs 62.5% ± 9.6%, p = 0.579), eNOS (66.3% ± 4.2% vs 63.8% ± 7.5%, p = 0.962), and caveolin (53.8% ± 5.0% vs 51.3% ± 4.4%, p = 0.922). There were no significant differences between the groups in the distributions of stain intensity for CD31, vWF, eNOS, and caveolin. Conclusion: Trimmed CVCs do not increase endothelial injury compared to standard untrimmed CVCs.

National Institutes of Health (NIH) funding has declined among cardiothoracic surgeons. R01 grants are a well-known mechanism to support high-impact research, and we sought to clarify the association between NIH funding and academic achievement. We hypothesized that cardiothoracic surgeons who acquired R01 funding exhibit greater research output and faster career advancement. All cardiothoracic surgeons (n = 992) working at accredited United States cardiothoracic surgery training hospitals in 2018 were included. Institutional webpages, Scopus, and Grantome were utilized to collect publicly-available data regarding each surgeon's training and career history, research publications, and NIH funding. Seventy-eight (7.9%) surgeons obtained R01 funding as a principal investigator while 914 (92.1%) did not. R01-funded surgeons started their attending careers earlier (1998 vs 2005, P0.0001) and were more likely to have pursued dedicated research training (P0.0001). R01-funded surgeons authored 5.3 publications/year before their first R01 grant, 9.3 during the grant period, and 8.6 after the grant expired, all of which were greater than the publication rate of non-R01-funded surgeons at comparable career timepoints (2.0-3.0 publications/year, P0.0001). Among time-matched surgeons who completed medical school in 1998 or earlier (n = 73 R01-funded vs n = 602 non-funded), R01-funded surgeons have published more total publications (178.0 vs 56.5 papers, P0.0001) and exhibit a greater H-index (41.0 vs 19.0, P0.0001). These R01-funded surgeons have also advanced to higher academic ranks (P0.0001) and are more likely to be chiefs of their departments or divisions (42.5% vs 25.7%, P = 0.0035). Cardiothoracic surgeons who obtain R01 funding exhibit greater research productivity and faster career advancement.

Introduction: National Institutes of Health (NIH) grants are an essential funding source for cardiothoracic (CT) surgeon-scientists. The association between NIH funding and an article’s research impact, however, has not been explored. We hypothesized that CT surgery research articles supported by NIH funding exhibit enhanced scholarly impact. Methods: Research records and NIH funding history for all CT surgery faculty (n=992) at accredited United States CT surgery training institutions in 2018 were obtained using Scopus and Grantome, respectively. Using the NIH iCite database, all articles published by these surgeons were classified as either basic science research (BSR, iCite animal or molecular/cellular score >0) or clinical research (CR, iCite animal and molecular/cellular score = 0). The relative citation ratio (RCR), an NIH-validated field-normalized metric of scholarly impact, was calculated for each article, where RCR 1.00 indicates equal impact as other NIH-funded articles in the same field, and RCR 2.00 indicates twice the impact. Data are presented as median [interquartile range] and analyzed using the Mann-Whitney test. Results: A total of 37,402 unique articles were identified, including 9,469 supported by NIH funding and 27,933 without NIH funding. CT surgery research articles with NIH funding exhibit a significantly greater median RCR than those without NIH funding (1.08 [0.53-2.19] vs 0.75 [0.28-1.72], p Conclusions: At single-article resolution, CT surgery research publications supported by NIH grant funding exhibit enhanced scholarly impact and compare favorably in median RCR versus other NIH-funded biomedical research.

The 331 million people of the United States are served by a complex and expensive healthcare system that accounts for nearly 18% of the country’s gross domestic product. Over 90% of patients are insured by private or government-funded plans, but despite high coverage and unusually high healthcare spending, vast disparities exist within the United States population based on demographics in terms of diagnosis, treatment, and outcomes of disease. Thoracic surgeons in the United States are trained to treat patients with diseases of the chest in the operative and perioperative settings, and can accomplish this training through multiple highly competitive pathways. Thoracic surgeons perform an average of 135 operations each per year which address diseases of the lungs, trachea, esophagus, chest wall, mediastinum, and diaphragm. Video assisted thoracoscopic surgeries are the most commonly performed procedures, which are primarily completed to treat lung cancer. Lung cancer is the deadliest and second most prevalent malignancy in the United States, with over 200,000 new cases expected this year. In addition to encouragement of smoking cessation and more attention to air pollutants, increased access to lung cancer screening has significantly expedited diagnosis and reduced mortality from lung cancer in the last several years. Thoracic surgeons in the United States are tasked with treating common yet highly morbid diseases of the chest in a patient population that is diverse in terms of race, socioeconomic status, and healthcare insurance coverage. As the population ages and a shortage of thoracic surgeons looms, the importance of early diagnosis, skillful surgical management, and attention to the disparities that exist in our system cannot be overstated.

Adverse remodeling of the left ventricle (LV) after myocardial infarction (MI) results in abnormal tissue biomechanics and impaired cardiac function, often leading to heart failure. We hypothesized that intramyocardial delivery of engineered stromal cell-derived factor 1α analog (ESA), our previously-developed supra-efficient proangiogenic chemokine, preserves biaxial LV mechanical properties after MI. Male Wistar rats (n = 45) underwent sham surgery (n = 15) or permanent left anterior descending coronary artery ligation. Rats sustaining MI were randomized for intramyocardial injections of either saline (100 μL, n = 15) or ESA (6 μg/kg, n = 15), delivered at four standardized borderzone sites. After 4 weeks, echocardiography was performed, and the hearts were explanted. Tensile testing of the anterolateral LV wall was performed using a displacement-controlled biaxial load frame, and modulus was determined after constitutive modeling. At 4 weeks post-MI, compared to saline controls, ESA-treated hearts had greater wall thickness (1.68 ± 0.05 mm vs 1.42 ± 0.08 mm, p = 0.008), smaller end-diastolic LV internal dimension (6.88 ± 0.29 mm vs 7.69 ± 0.22 mm, p = 0.044), and improved ejection fraction (62.8 ± 3.0% vs 49.4 ± 4.5%, p = 0.014). Histologic analysis revealed significantly reduced infarct size for ESA-treated hearts compared to saline controls (29.4 ± 2.9% vs 41.6 ± 3.1%, p = 0.021). Infarcted hearts treated with ESA exhibited decreased modulus compared to those treated with saline in both the circumferential (211.5 ± 6.9 kPa vs 264.3 ± 12.5 kPa, p = 0.001) and longitudinal axes (194.5 ± 6.5 kPa vs 258.1 ± 14.4 kPa, p < 0.001). In both principal directions, ESA-treated infarcted hearts possessed similar tissue compliance as sham non-infarcted hearts. Overall, intramyocardial ESA therapy improves post-MI ventricular remodeling and function, reduces infarct size, and preserves native LV biaxial mechanical properties.

Cardiothoracic (CT) surgeons with National Institutes of Health (NIH) R01 funding face a highly competitive renewal process. The factors that contribute to successful grant renewal for CT surgeons remain poorly defined. We hypothesized that renewed basic science grants are associated with high research output and scholarly impact during the preceding award cycle.Using a database of academic CT surgeons (n = 992) at accredited training institutions in 2018, we identified basic science R01 grants awarded to CT surgeon principal investigators since 1985. Data for each award were obtained from publicly available online sources. Scholarly impact was evaluated using the NIH-validated relative citation ratio (RCR), defined as an article's citation rate divided by that of R01-funded publications in the same field. Continuous data are presented as medians and analyzed using the Mann-Whitney test.We identified 102 basic science R01 award cycles, including 33 that were renewed (32.4%). Renewed and nonrenewed awards had a similar start year and funding period. Principal investigators of renewed versus nonrenewed awards were similar in surgical subspecialty, research training, attending experience, academic rank, and previous NIH funding. Renewed awards produced more publications per year over the funding cycle (3.4 vs 1.5;CT surgery basic science R01 grants are associated with high research output and scholarly impact. At the 50th percentile among renewed grants, CT surgeons published 3.4 funded manuscripts per year with a median RCR of 0.84 during the previous award cycle.

Introduction: There is growing concern regarding the attrition of surgeon-scientists in cardiothoracic (CT) surgery. The academic impact of conducting basic science research (BSR) during training, however, remains unknown. We hypothesized that CT surgeons who publish a first-author BSR paper during training exhibit enhanced future academic productivity. Methods: CT surgeons on faculty at accredited United States CT surgery training hospitals in 2018 who published a first-author BSR paper or a first-author clinical research (CR) paper during training were identified (n=762). To normalize for environmental differences in research exposure, we specifically studied the surgeons who pursued a research fellowship and who attended a top-50 NIH-funded institution at every stage of training (n=252). Data regarding each surgeon’s professional history and publication record were obtained from publicly-available online sources. Results: As shown in Table 1, surgeons who published a first-author paper in BSR during training and those who published a first-author paper only in CR share similar characteristics and have practiced as an attending surgeon for a similar duration (11.0 years each, p=0.486). However, surgeons who published a first-author BSR paper during training ultimately published more papers per year as an attending (4.3 vs 2.8, p=0.017), resulting in more total publications (73.5 vs 47.5, p=0.003) and a greater H-index (22.0 vs 18.0, p=0.004). The surgeons who published a first-author BSR paper during training were also more likely to have published a BSR paper in the past 2 years as an attending, both as a first or last author (12.0% vs 2.0%, p=0.004), or as a co-author (34.0% vs 15.7%, p=0.001). Conclusions: Academic CT surgeons who published a first-author BSR paper during training exhibit enhanced research productivity and scholarly impact. Funding and institutional support for aspiring CT surgeon-scientists may yield career-long academic benefits.

After myocardial infarction (MI), adult mammals exhibit scar formation, adverse left ventricular (LV) remodeling, LV stiffening, and impaired contractility, ultimately resulting in heart failure. Neonatal mammals, however, are capable of natural heart regeneration after MI. We hypothesized that neonatal cardiac regeneration conserves native biaxial LV mechanics after MI. Wistar rat neonates (1 day old, n = 46) and adults (8-10 weeks old, n = 20) underwent sham surgery or permanent left anterior descending coronary artery ligation. At 6 weeks after neonatal MI, Masson's trichrome staining revealed negligible fibrosis. Echocardiography for the neonatal MI (n = 15) and sham rats (n = 14) revealed no differences in LV wall thickness or chamber diameter, and both groups had normal ejection fraction (72.7% vs 77.5%, respectively, p = 0.1946). Biaxial tensile testing revealed similar stress-strain curves along both the circumferential and longitudinal axes across a full range of physiologic stresses and strains. The circumferential modulus (267.9 kPa vs 274.2 kPa, p = 0.7847), longitudinal modulus (269.3 kPa vs 277.1 kPa, p = 0.7435), and maximum shear stress (3.30 kPa vs 3.95 kPa, p = 0.5418) did not differ significantly between the neonatal MI and sham groups, respectively. In contrast, transmural scars were observed at 4 weeks after adult MI. Adult MI hearts (n = 7) exhibited profound LV wall thinning (p 0.0001), chamber dilation (p = 0.0246), and LV dysfunction (ejection fraction 45.4% vs 79.7%, p 0.0001) compared to adult sham hearts (n = 7). Adult MI hearts were significantly stiffer than adult sham hearts in both the circumferential (321.5 kPa vs 180.0 kPa, p = 0.0111) and longitudinal axes (315.4 kPa vs 172.3 kPa, p = 0.0173), and also exhibited greater maximum shear stress (14.87 kPa vs 3.23 kPa, p = 0.0162). Our study is the first to show that native biaxial LV mechanics are conserved after neonatal heart regeneration following MI, thus adding biomechanical support for the therapeutic potential of cardiac regeneration in the treatment of ischemic heart disease.

The Stanford classification of aortic dissection was described in 1970. The classification proposed that type A aortic dissection should be surgically repaired immediately, whereas type B aortic dissection can be treated medically. Since then, diagnostic tools and management of acute type A aortic dissection (ATAAD) have undergone substantial evolution. This paper evaluated historical changes of ATAAD repair at Stanford University since the establishment of the aortic dissection classification 50 years ago. The surgical approaches to the proximal and distal extent of the aorta, cerebral perfusion methods, and cannulation strategies were reviewed. Additional analyses using patients who underwent ATAAD repair at Stanford University from 1967 through December 2019 were performed to further illustrate the Stanford experience in the management of ATAAD. While technical complexity increased over time, post-operative survival continued to improve. Further investigation is warranted to delineate factors associated with the improved outcomes observed in this study.

The foundation for a successful academic surgical career begins in medical school. We examined whether attending a top-ranked medical school is correlated with enhanced research productivity and faster career advancement among academic cardiothoracic (CT) surgeons.Research profiles and professional histories were obtained from publicly available sources for all CT surgery faculty at accredited US CT surgery teaching hospitals in 2018 (n = 992). We focused on surgeons who completed medical school in the United States during or after 1990, the first-year US NewsWorld Report released its annual medical school research rankings (n = 451). Subanalyses focused on surgeons who completed a research fellowship (n = 299) and those who did not (n = 152).A total of 124 surgeons (27.5%) attended a US NewsWorld Report top 10 medical school, whereas 327 (72.5%) did not. Surgeons who studied at a top 10 medical school published more articles per year as an attending surgeon (3.2 versus 1.9; P 0.0001), leading to more total publications (51.5 versus 27.0; P 0.0001) and a higher H-index (16.0 versus 11.0; P 0.0001) over a similar career duration (11.0 versus 10.0 y; P = 0.1294). These differences in career-long research productivity were statistically significant regardless of whether the surgeons completed a research fellowship or not. The surgeons in both groups, however, required a similar number of years to reach associate professor rank (P = 0.6993) and full professor rank (P = 0.7811) after starting their first attending job.Attending a top-ranked medical school is associated with enhanced future research productivity but not with faster career advancement in academic CT surgery.

Advanced clinical fellowships are important for training surgeons with a niche expertise. Whether this additional training impacts future academic achievement, however, remains unknown. Here, we investigated the impact of advanced fellowship training on research productivity and career advancement among active, academic cardiac surgeons. We hypothesized that advanced fellowships do not significantly boost future academic achievement.Using online sources (eg, department webpages, CTSNet, Scopus, Grantome), we studied adult cardiac surgeons who are current faculty at accredited United States cardiothoracic surgery training programs, and who have practiced only at United States academic centers since 1986 (n = 227). Publicly available data regarding career advancement, research productivity, and grant funding were collected. Data are expressed as counts or medians.In our study, 78 (34.4%) surgeons completed an advanced clinical fellowship, and 149 (65.6%) did not. Surgeons who pursued an advanced fellowship spent more time focused on surgical training (P.0001), and those who did not were more likely to have completed a dedicated research fellowship (P = .0482). Both groups exhibited similar cumulative total publications (P = .6862), H-index (P = .6232), frequency of National Institutes of Health grant funding (P = .8708), and time to achieve full professor rank (P = .7099). After stratification by current academic rank, or by whether surgeons pursued a dedicated research fellowship, completion of an advanced clinical fellowship was not associated with increased research productivity or accelerated career advancement.Academic adult cardiac surgeons who pursue advanced clinical fellowships exhibit similar research productivity and similar career advancement as those who do not pursue additional clinical training.

A first attending job often sets the tone for academic surgeons' future careers, and many graduating trainees are faced with the decision to begin their career at their training institution or another institution. We hypothesized that surgeons hired as first-time faculty at their cardiothoracic surgery fellowship institution exhibit greater research productivity and career advancement than those hired as first-time faculty at a different institution.Cardiothoracic surgeons who were listed as clinical faculty at all 77 accredited United States cardiothoracic surgery training programs in 2018 and who trained through the general surgery residency and cardiothoracic surgery fellowship pathway were included (n = 904). Surgeon-specific data regarding professional history, publications, and grant funding were obtained from publicly available sources.Of the 904 surgeons, 294 (32.5%) were hired as first-time faculty at their cardiothoracic surgery fellowship institution whereas 610 (67.5%) were hired at a different institution (start year 2005 vs 2006; P = .342). Both groups exhibited similar research productivity upon starting their first job (total papers: 7.0 vs 7.0, P = .591). Followed to the present, surgeons hired at their cardiothoracic surgery fellowship institution produced more total papers (64.5 vs 39.0, P.001) and exhibited a higher H-index (20.0 vs 14.0, P.001). Surgeons in both groups required a similar amount of time to achieve associate (P = .208) and full professor (P = .593) ranks.Surgeons hired as first-time faculty at their cardiothoracic surgery fellowship institution may experience benefits to research productivity but not career advancement. Trainees may find it advantageous to begin their careers in a familiar environment where they have already formed a robust specialty-specific network.

Summary The cyanobacterium Synechococcus elongatus (SE) has been shown to rescue ischaemic heart muscle after myocardial infarction by photosynthetic oxygen production. Here, we investigated SE toxicity and hypothesized that systemic SE exposure does not elicit a significant immune response in rats. Wistar rats intravenously received SE (n = 12), sterile saline (n = 12) or E. coli lipopolysaccharide (LPS, n = 4), and a subset (8 SE, 8 saline) received a repeat injection 4 weeks later. At baseline, 4 h, 24 h, 48 h, 8 days and 4 weeks after injection, clinical assessments, blood cultures, blood counts, lymphocyte phenotypes, liver function tests, proinflammatory cytokines and immunoglobulins were assessed. Across all metrics, SE rats responded comparably to saline controls, displaying no clinically significant immune response. As expected, LPS rats exhibited severe immunological responses. Systemic SE administration does not induce sepsis or toxicity in rats, thereby supporting the safety of cyanobacteria–mammalian symbiotic therapeutics using this organism., The cyanobacterium Synechococcus elongatus (SE) has been shown to rescue ischemic heart muscle after myocardial infarction by photosynthetic oxygen production. Here, we investigate SE toxicity by systemically administering SE to rats and evaluating their immune response by way of clinical assessments, blood cultures, blood counts, lymphocyte phenotypes, liver function tests, proinflammatory cytokines, immunoglobulins, and tissue histology. Systemic SE administration does not induce sepsis or toxicity in rats, thereby supporting the safety of cyanobacteria‐mammalian symbiotic therapeutics using this organism.

Although ischemic heart disease is the leading cause of death worldwide, mainstay treatments ultimately fail because they do not adequately address disease pathophysiology. Restoring the microvascular perfusion deficit remains a significant unmet need and may be addressed via delivery of pro-angiogenic cytokines. The therapeutic effect of cytokines can be enhanced by encapsulation within hydrogels, but current hydrogels do not offer sufficient clinical translatability due to unfavorable viscoelastic mechanical behavior which directly impacts the ability for minimally-invasive catheter delivery. In this report, we examine the therapeutic implications of dual-stage cytokine release from a novel, highly shear-thinning biocompatible catheter-deliverable hydrogel. We chose to encapsulate two protein-engineered cytokines, namely dimeric fragment of hepatocyte growth factor (HGFdf) and engineered stromal cell-derived factor 1α (ESA), which target distinct disease pathways. The controlled release of HGFdf and ESA from separate phases of the hyaluronic acid-based hydrogel allows extended and pronounced beneficial effects due to the precise timing of release. We evaluated the therapeutic efficacy of this treatment strategy in a small animal model of myocardial ischemia and observed a significant benefit in biological and functional parameters. Given the encouraging results from the small animal experiment, we translated this treatment to a large animal preclinical model and observed a reduction in scar size, indicating this strategy could serve as a potential adjunct therapy for the millions of people suffering from ischemic heart disease.

Intercellular communication is essential to coordinate the behaviour of individual cells during organismal development. The preimplantation mammalian embryo is a paradigm of tissue self-organization and regulative development; however, the cellular basis of these regulative abilities has not been established. Here we use a quantitative image analysis pipeline to undertake a high-resolution, single-cell level analysis of lineage specification in the inner cell mass (ICM) of the mouse blastocyst. We show that a consistent ratio of epiblast and primitive endoderm lineages is achieved through incremental allocation of cells from a common progenitor pool, and that the lineage composition of the ICM is conserved regardless of its size. Furthermore, timed modulation of the FGF-MAPK pathway shows that individual progenitors commit to either fate asynchronously during blastocyst development. These data indicate that such incremental lineage allocation provides the basis for a tissue size control mechanism that ensures the generation of lineages of appropriate size., Early embryonic cell fate and lineage specification is tightly regulated in the preimplantation mammalian embryo. Here, the authors quantitatively examine the ratio of epiblast to primitive endoderm lineages in the blastocyst and show composition of the inner cell mass is conserved, independent of its size.

Introduction: Adverse remodeling of the left ventricle (LV) after myocardial infarction (MI) results in abnormal tissue biomechanics and impaired cardiac function, ultimately leading to heart failure. We hypothesized that intramyocardial delivery of engineered stromal cell-derived factor 1α analog (ESA), our previously-developed supra-efficient pro-angiogenic chemokine, preserves biaxial LV mechanical properties after MI. Methods: Male Wistar rats (n=46) underwent sham surgery (n=15) or permanent left anterior descending coronary artery ligation (n=31). Rats sustaining MI were randomized for intramyocardial injections of either saline (100 μL, n=15) or ESA (6 μg/kg, n=16), delivered at standardized peri-infarct sites. After 4 weeks, echocardiography was performed, and the hearts were explanted. Biaxial tensile testing of the anterior LV wall was performed using a strain-controlled biaxial load frame (Fig. 1A), producing up to physiologic circumferential and longitudinal strains (ε=20%, each). The modulus was determined along each axis, and maximum shear stress was calculated as a composite metric of the tissue’s response to physiologic strains. Data are expressed as mean±SEM. Results: At 4 weeks post-MI, ESA-treated hearts had smaller end-diastolic LV internal dimension (6.89±0.27 cm vs 7.69±0.22 cm, p=0.03) and improved ejection fraction (63.7±2.9% vs 49.4±4.4%, p=0.01) compared to saline-injected controls. Hearts treated with ESA exhibited lower moduli than saline controls in both the circumferential (269.4±33.2 kPa vs 431.5±55.6 kPa, p=0.02) and longitudinal axes (182.4±25.0 kPa vs 332.3±51.2 kPa, p=0.02, Fig. 1B). The maximum shear stress for ESA-treated hearts was significantly reduced compared to that for saline controls (5.8±0.8 kPa vs 9.0±1.2 kPa, p=0.03) and was similar to that for sham controls (Fig. 1C). Conclusion: Intramyocardial ESA injection mitigates post-MI tissue stiffening and preserves biaxial LV mechanical properties.

Introduction: The posterior ventricular anchoring neochordal (PVAN) repair is a nonresectional, single-suture technique for correcting posterior leaflet prolapse. While this technique has demonstrated clinical efficacy, a possible limitation is the stability of the suture anchored into myocardium as opposed to the fibrous portion of a papillary muscle. Hypothesis: We hypothesize that the PVAN suture serves only to position the leaflet for coaptation, after which systolic forces will be distributed throughout the valve, resulting in low peak forces on the suture. Methods: A left heart simulator was constructed using 3D printing, tuned to generate physiological pressure and flow waveforms, then validated. Porcine mitral valves (n=9) were dissected and mounted within the simulator. Chordal forces were measured using Fiber Bragg Grating (FBG) sensors, sewn in place using PTFE suture. FBG sensors are strain gauges made of 125 μ m optical fibers that use reflected peak wavelength changes to measure strain. Hemodynamic and echocardiographic data were also collected. Isolated severe mitral regurgitation (MR) was induced by cutting P2 primary chordae. The valve was repaired using the PVAN technique, anchoring the suture to a customized force-sensing post positioned to mimic in vivo placement. Results: Forces on 1° and 2° chordae of both anterior and posterior leaflets were significantly elevated in the prolapse condition ( P < 0.05). PVAN resulted in elimination of MR in all valves, as well as normalization of chordae forces to baseline levels for posterior primary ( P < 0.01 ) , posterior secondary ( P < 0.01 ) , and anterior primary chordae ( P < 0.05 ) , with reduction in anterior secondary chordal forces approaching significance ( P = 0.055 ) . Peak forces on the PVAN stitch were minimal, even compared to the forces experienced by primary chordae of normal, healthy valves ( P < 0.05). Conclusions: The PVAN technique eliminates MR by effectively positioning the posterior leaflet for optimal coaptation, distributing the forces amongst the subvalvular apparatus. Given the extremely low forces involved, the strength of the ventricular anchoring suture and myocardial anchoring point should not be a limiting factor.

Introduction: Very few technologies exist that can provide quantitative data on forces within the mitral valve apparatus. Marker based strain measurements can be performed, but chordae heterogeneity limits utility. Foil-based strain sensors have also been described, but tend to be bulky, limiting the number of chordae that can be measured. Hypothesis: We hypothesize that the use of Fiber Bragg Grating (FBG) sensors—optical strain gauges made of 125 μ m diameter silica fibers— can overcome the critical limitations of previous methods of measuring chordae tendineae forces. Methods: Using FBG sensors, we created a force-sensing neochord that would mimic the natural shape and movement of native chordae tendineae. FBG sensors reflect a specific wavelength of light depending on the spatial period of gratings - when a force is applied, the gratings move relative to one another, changing the reflected light (Fig 1A). This wavelength shift is directly proportional to the force applied. The FBG sensors were housed in a protective sheath fashioned from the outer coil of a 0.025" Amplatz Extra-Stiff guidewire, and attached to the chordae using GoreTex suture (Fig 1B). The function of the force-sensing neochordae were validated in a 3D printed left heart simulator. Results: FBG sensors provided high-fidelity force measurements of mitral valve chordae tendineae at a temporal resolution of 1000 Hz. As ventricular pressures increased, such as in the hypertensive condition, forces on the chordae also increased (Fig 1C). The resolution of FBG sensors allow for increased accuracy of not only chordae tension, but also the rate of change of force (dF/dt) - a parameter critical to determining likelihood of leaflet rupture. Conclusions: FBG sensors are a viable, durable, and high-fidelity technology that can be effectively used to measure mitral valve chordae forces and overcome limitations of other such technologies.

Post-operative adhesions form as a result of normal wound healing processes following any type of surgery. In cardiac surgery, pericardial adhesions are particularly problematic during reoperations, as surgeons must release the adhesions from the surface of the heart before the intended procedure can begin, thereby substantially lengthening operation times and introducing risks of haemorrhage and injury to the heart and lungs during sternal re-entry and cardiac dissection. Here we show that a dynamically crosslinked supramolecular polymer-nanoparticle hydrogel, with viscoelastic and flow properties that enable spraying onto tissue as well as robust tissue adherence and local retention in vivo for two weeks, reduces the formation of pericardial adhesions. In a rat model of severe pericardial adhesions, the hydrogel markedly reduced the severity of the adhesions, whereas commercial adhesion barriers (including Seprafilm and Interceed) did not. The hydrogels also reduced the severity of cardiac adhesions (relative to untreated animals) in a clinically relevant cardiopulmonary-bypass model in sheep. This viscoelastic supramolecular polymeric hydrogel represents a promising clinical solution for the prevention of post-operative pericardial adhesions.