Heterogeneous Cardiac- and Neural Crest-Derived Aortic Smooth Muscle Cells have Similar Transcriptional Changes after TGFβ Signaling Disruption

Smooth muscle cells (SMCs) of cardiac and neural crest origin contribute to the developing proximal aorta and are linked to disease propensity in adults. We analyzed single-cell transcriptomes of SMCs from mature thoracic aortas in mice to determine basal states and changes after disrupting transforming growth factor-β (TGFβ) signaling necessary for aortic homeostasis. A minority of Myh11 lineage-marked SMCs differentially expressed genes suggestive of embryological origin. Additional analyses in Nkx2-5 and Wnt1 lineage-marked SMCs derived from cardiac and neural crest progenitors, respectively, showed both lineages contributed to a major common cluster and each lineage to a minor distinct cluster. Common cluster SMCs extended from root to arch, cardiac subset cluster SMCs from root to mid-ascending, while neural crest subset cluster SMCs were restricted to the arch. The neural crest subset cluster had greater expression of a subgroup of TGFβ-dependent genes suggesting specific responsiveness or skewed extracellular matrix synthesis. Nonetheless, deletion of TGFβ receptors in SMCs resulted in similar transcriptional changes among all clusters, primarily decreased extracellular matrix molecules and modulators of TGFβ signaling. Many embryological markers of murine aortic SMCs were not confirmed in adult human aortas. We conclude: (i) there are multiple subtypes of cardiac- and neural crest-derived SMCs with shared or distinctive transcriptional profiles, (ii) neural crest subset SMCs with increased expression of certain TGFβ-inducible genes are not spatially linked to the aortic root predisposed to aneurysms from aberrant TGFβ signaling, and (iii) loss of TGFβ responses after receptor deletion is uniform among SMCs of different embryological origins.

Short-Term Disruption of TGFβ Signaling in Adult Mice Renders the Aorta Vulnerable to Hypertension-Induced Dissection

Hypertension and transient increases in blood pressure from extreme exertion are risk factors for aortic dissection in patients with age-related vascular degeneration or inherited connective tissue disorders. Yet, the common experimental model of angiotensin II-induced aortopathy in mice appears independent of high blood pressure as lesions do not occur in response to an alternative vasoconstrictor, norepinephrine, and are not prevented by co-treatment with a vasodilator, hydralazine. We investigated vasoconstrictor administration to adult mice 1 week after disruption of TGFβ signaling in smooth muscle cells. Norepinephrine increased blood pressure and induced aortic dissection by 7 days and even within 30 minutes that was rescued by hydralazine; results were similar with angiotensin II. Changes in regulatory contractile molecule expression were not of pathological significance. Rather, reduced synthesis of extracellular matrix yielded a vulnerable aortic phenotype by decreasing medial collagen, most dynamically type XVIII, and impairing cell-matrix adhesion. We conclude that transient and sustained increases in blood pressure cause dissection in aortas rendered vulnerable by inhibition of TGFβ-driven extracellular matrix production by smooth muscle cells. A corollary is that medial fibrosis, a frequent feature of medial degeneration, may afford some protection against aortic dissection.

Intimomedial tears of the aorta heal by smooth muscle cell-mediated fibrosis without atherosclerosis

BACKGROUNDDisease of the aorta varies from atherosclerosis to aneurysms, with complications including rupture, dissection, and poorly characterized limited tears. We studied limited tears without any mural hematoma, termed intimomedial tears, to gain insight into aortic vulnerability to excessive wall stresses. Our premise is that minimal injuries in aortas with sufficient medial resilience to prevent tear progression correspond to initial mechanisms leading to complete structural failure in aortas with significantly compromised medial resilience.METHODSIntimomedial tears were macroscopically identified in 9 of 108 ascending aortas after surgery and analyzed by histology and immunofluorescence confocal microscopy.RESULTSNonhemorrhagic, nonatheromatous tears correlated with advanced aneurysmal disease and most lacked distinctive symptoms or radiological signs. Tears traversed the intima and part of the subjacent media, while the resultant defects were partially or completely filled with neointima characterized by differentiated smooth muscle cells, scattered leukocytes, dense fibrosis, and absent elastic laminae despite tropoelastin synthesis. Healed lesions contained organized fibrin at tear edges without evidence of plasma and erythrocyte extravasation or lipid accumulation.CONCLUSIONThese findings suggest a multiphasic model of aortic wall failure in which primary lesions of intimomedial tears either heal if the media is sufficiently resilient or progress as dissection or rupture by medial delamination and tear completion, respectively. Moreover, mural incorporation of thrombus and cellular responses to injury, two historically important concepts in atheroma pathogenesis, contribute to vessel wall repair with adequate conduit function, but even together are not sufficient to induce atherosclerosis.FUNDINGNIH (R01-HL146723, R01-HL168473) and Yale Department of Surgery.

Thoracic aortic aneurysm in an adolescent with intraoperative discovery of contained rupture: a case report

Background

As surgical recommendations in adults based on size criteria of ascending aortic aneurysms become more refined, criteria for childhood/adolescence remains less clear. Multiple pathologic factors may predispose younger patients to thoracic aortic aortopathy and increase the risk of rupture. An evolving field of research is how to identify thoracic aortic dilation earlier in patients, risk stratify, and to obtain objective measures beyond size for proceeding with surgical intervention in order to prevent catastrophic thoracic aortic dissection.

Case Description

We report an adolescent case of dilated ascending aortic aneurysm with a functionally unicuspid/bicuspid aortic valve. This patient was taken to surgery electively, given the gradual increasing size of the ascending aorta. Intraoperatively, there was an unexpected intraoperative finding of a contained aortic rupture. The patient underwent an aortic root replacement with mechanical valve composite graft and coronary artery reimplantation (modified Bentall) with ascending hemiarch replacement. The patient did well with no post-operative complications. Aortic pathology and genetic analysis were performed. The patient was discovered to have a heterozygous variant in PTPN11 which is typically associated with Noonan syndrome; however, this is not known to be associated with aortopathy.

Conclusions

As criteria for surgical intervention in adult thoracic ascending aortic aneurysms continues to evolve, this case illustrates challenges when determining the optimal criteria for surgical intervention in adolescent patients.

Living in disadvantaged neighborhoods linked to less intervention for severe aortic stenosis

To investigate the association between area deprivation index (ADI) and aortic valve replacement (AVR) in patients with severe aortic stenosis (AS). Patients aged 40-95 years with severe AS confirmed by echocardiography were included. The 9-digit zip code of patient residence address was used to identify the ADI ranking, based on which patients were divided into 5 groups (with Group E being most deprived). The rates of AV intervention were compared among 5 groups using competing risks analysis, with death as a competing event. We included 1751 patients with severe AS from 2013 to 2018 followed for a median 2.8 (interquartile range, 1.5-4.8) years. The more distressed ADI groups tended to be younger (P = 0.002), female (P < 0.001), and of African American race (P < 0.001), have higher presentation of sepsis (P = 0.031), arrhythmia (P = 0.022), less likely to have previous diagnosis of AS (P < 0.001); and were less likely to undergo AVR (52.5% vs 46.9% vs 46.1% vs 48.9% vs 39.7%, P = 0.023). Using competing risk analysis, the highest ADI group (E) were the least and the lowest ADI group (A) the most likely to undergo AVR (Gray's test, P = 0.025). The association between ADI ranking and AVR rates was influenced by sex and race. Within group analysis, there was significant association between race and AVR (Gray's test, P < 0.001), and between sex and AVR (Gray's test, P < 0.001). Patients with severe AS living in more deprived neighborhoods were less likely to undergo aortic valve interventions, which was influenced by female gender, and African American race.

Aortic remodeling following hybrid arch repair with zone 0 to 5 thoracic endovascular aortic repairs for complex arch and descending thoracic aortic pathologies

Objective

For high-risk patients with aortic arch pathology, hybrid aortic arch repair with simultaneous or staged thoracic endovascular repair of the descending aorta may be a viable alternative to open repair. However, data on postintervention aortic remodeling remain limited. We report the short-term outcomes of remodeling of the thoracoabdominal aorta after hybrid arch repair + thoracic endovascular repair.

Methods

All patients undergoing hybrid arch repair with planned zones 0 to 5 thoracic endovascular repair from January 2020 to March 2022 were retrospectively reviewed. Computed tomography angiography scans preoperatively, after hybrid aortic arch repair, and on long-term follow-up were analyzed for thoracoabdominal aorta remodeling. Mean change in aortic true luminal diameter and full luminal diameter was calculated at every level, and paired-samples t test was used to compare means.

Results

Of 39 patients, 38 had follow-up data at a mean duration of 14.9 months. There were a total of 3 (7.7%) deaths, 0 (0.0%) strokes, and 0 (0.0%) paralysis. For the 35 patients undergoing thoracic endovascular repair for aortic dissection, at follow-up, there was a significant increase in the mean true luminal diameter at each level (P < .05), except at the aortic bifurcation and common iliac arteries. The largest increase in mean true luminal diameter (P < .01) was observed at the level of the left inferior pulmonary vein (mean difference +13.22 mm, 95% CI, 10.38-16.07), tracheal carina (mean difference +13.06 mm, 95% CI, 10.05-16.07), and inferior left atrium (mean difference +11.19 mm, 95% CI, 7.84-14.53).

Conclusions

Hybrid arch repair with zones 0 to 5 leads to improved true lumen augmentation in zones 0 to 8 with complete false lumen thrombosis down to zone 5 at short-term follow-up. Zones 9 to 11, if involved, may require adjunctive treatment strategies for total aortic remodeling and complete false lumen obliteration.

Effects of RBT-1 on preconditioning response biomarkers in patients undergoing coronary artery bypass graft or heart valve surgery: a multicentre, double-blind, randomised, placebo-controlled phase 2 trial

Background

RBT-1 is a combination drug of stannic protoporfin (SnPP) and iron sucrose (FeS) that elicits a preconditioning response through activation of antioxidant, anti-inflammatory, and iron-scavenging pathways, as measured by heme oxygenase-1 (HO-1), interleukin-10 (IL-10), and ferritin, respectively. Our primary aim was to determine whether RBT-1 administered before surgery would safely and effectively elicit a preconditioning response in patients undergoing cardiac surgery.

Methods

This phase 2, double-blind, randomised, placebo-controlled, parallel-group, adaptive trial, conducted in 19 centres across the USA, Canada, and Australia, enrolled patients scheduled to undergo non-emergent coronary artery bypass graft (CABG) and/or heart valve surgery with cardiopulmonary bypass. Patients were randomised (1:1:1) to receive either a single intravenous infusion of high-dose RBT-1 (90 mg SnPP/240 mg FeS), low-dose RBT-1 (45 mg SnPP/240 mg FeS), or placebo within 24-48 h before surgery. The primary outcome was a preoperative preconditioning response, measured by a composite of plasma HO-1, IL-10, and ferritin. Safety was assessed by adverse events and laboratory parameters. Prespecified adaptive criteria permitted early stopping and enrichment. This trial is registered with ClinicalTrials.gov, NCT04564833.

Findings

Between Aug 4, 2021, and Nov 9, 2022, of 135 patients who were enrolled and randomly allocated to a study group (46 high-dose, 45 low-dose, 44 placebo), 132 (98%) were included in the primary analysis (46 high-dose, 42 low-dose, 44 placebo). At interim, the trial proceeded to full enrollment without enrichment. RBT-1 led to a greater preconditioning response than did placebo at high-dose (geometric least squares mean [GLSM] ratio, 3.58; 95% CI, 2.91-4.41; p < 0.0001) and low-dose (GLSM ratio, 2.62; 95% CI, 2.11-3.24; p < 0.0001). RBT-1 was generally well tolerated by patients. The primary drug-related adverse event was dose-dependent photosensitivity, observed in 12 (26%) of 46 patients treated with high-dose RBT-1 and in six (13%) of 45 patients treated with low-dose RBT-1 (safety population).

Interpretation

RBT-1 demonstrated a statistically significant cytoprotective preconditioning response and a manageable safety profile. Further research is needed. A phase 3 trial is planned.

Funding

Renibus Therapeutics, Inc.

TAVR explant with aortic root replacement using a homograft for an aortic rupture

This case report describes the explantation of an Evolut PRO valve 9 months after implantation in a 69-year-old male presenting with an aortic rupture adjacent to the stent frame of the prosthesis. Imaging was consistent with aortic sinus pseudoaneurysm and a large haemopericardium. Degeneration of the aortic root compounded by the transcatheter prosthesis in addition to the aortic rupture required replacement of the aortic root. The complexity of the procedure also required a modified Cabrol extension of the left coronary button and reconstruction of the left coronary button with bovine pericardium. We describe the technical challenges posed by the self-expanding transcatheter aortic valve prosthesis and tips and tricks to circumvent these challenges.

Variability in surveillance practice for patients with diagnosis of bicuspid aortic valve syndrome

In patients with bicuspid aortic valves, guidelines call for regular follow-up to monitor disease progression and guide intervention. We aimed to evaluate how closely these recommendations are followed at a tertiary care center. Among 48,504 patients who received echocardiograms (2013-2018) at a tertiary care center, 245 patients were identified to have bicuspid aortic valve. Bivariate analyses compared characteristics between patients who did and did not receive follow-up by a cardiovascular specialist. During a median follow-up of 3.5 ± 2.2 years (mean age 55.2 ± 15.6 years, 30.2% female), 72.7% of patients had at least one visit with a cardiovascular specialist after diagnosis of bicuspid aortic valve. These patients had a higher proportion of surveillance by echocardiogram (78.7% vs. 34.3%, p < .0001), CT or MRI (41.0% vs. 3.0%, p < .0001), and were more likely to undergo surgery. Patients with moderate-severe valvular or aortic pathology were not more likely to be followed by a specialist or receive follow-up echocardiograms. Follow-up care for patients with bicuspid aortic valve was highly variable, and surveillance imaging was sparse despite guidelines. There is an urgent need for mechanisms to monitor this population with increased risk of progressive valvulopathy and aortopathy.

Direct relationship between transvalvular velocity and cardiac dysfunction, morbidity, and mortality in patients with aortic stenosis

OBJECTIVE

Current guidelines recommend intervention in subjects with severe symptomatic aortic stenosis (AS), even though any degree of AS is associated with a higher risk of mortality. We investigated the association between the degree of AS, delineated by transvalvular flow velocity, and patient morbidity and mortality.

METHODS

Medically managed patients aged 40-95 years with maximum flow velocity (V_max ) by echocardiography between 2013 and 2018 were stratified into five groups (A-E) based on the 75th, 90th, 97.5th, and the 99th percentiles of V_max distribution. Patient characteristics, cardiac structural changes, and end-organ disease were compared using Kruskal-Wallis and Cochran-Armitage tests. Mortality over a median of 2.8 (1.52-4.8) years was compared using Kaplan-Meier curves and risk estimates were derived from the Cox model.

RESULTS

The V_max was reported in 37,131 patients. There was a steady increase (from Group A towards E) in age, Caucasian race, structural cardiac changes, end-organ morbidities, and all-cause mortality. In reference to Group A, there as an increased risk of mortality in Groups B (hazard ratio [HR] = 1.3; confidence interval [CI]: 1.2-1.35; p < .0001), C (HR = 1.5; CI: 1.4-1.6; p < .0001), and D (HR = 1.8; CI: 1.6-2; p < .0001), with an exponential increase in Group E (HR = 2.5; CI: 2.2-2.8; p < .0001).

CONCLUSIONS

A direct, strong correlation exists between the degree of AS and cardiac structural changes and mortality. Patients with V_max  ≥ 97.5th percentile (≥3.2 m/s) might benefit from early intervention.

Comprehensive review of hybrid aortic arch repair with focus on zone 0 TEVAR and our institutional experience

Even with increasing operator experience and a better understanding of the disease and the operation, intervention for aortic arch pathologies continues to struggle with relatively higher mortality, reintervention, and neurologic complications. The hybrid aortic arch repair was introduced to simplify the procedure and improve the outcome. With recent industry-driven advances, hybrid repairs are not only offered to poor surgical candidates but have become mainstream. This review discusses the evolution of hybrid repair, terminology pertinent to this technique, and results. In addition, we aim to provide a pervasive review of hybrid aortic arch repairs with reference to relevant literature for a detailed understanding. We have also discussed our institutional experience with hybrid repairs.

Long-term risk of arch complications in Loeys Dietz syndrome patients undergoing proximal ascending aortic replacement

PURPOSE

Loeys-Dietz syndrome (LDS) is a rare connective tissue disorder. In LDS patients with normal arch morphology, whether the arch should be prophylactically replaced at the time of proximal aortic replacement remains unknown. We evaluated the risk of long-term arch complications in genetically confirmed LDS patients who underwent proximal ascending aortic replacement.

METHODS

We retrospectively reviewed the records of patients with LDS who have been followed at our institution between 1994 and 2020. Patients were only included if whole exome genetic testing confirmed a mutation in an LDS-causing gene (TGFBR1, TGFBR2, SMAD3, TGFB2, or TGFB3). Mutations were categorized as pathogenic, benign, or of unknown significance. We collected demographic information, aortic dimensions, comorbidities, mortality, and operative course from patients' charts. Descriptive statistics and freedom from reoperation plots were generated.

RESULTS

Of the 18 patients with a mutation in an LDS-causing gene, 15 had known pathogenic variants, two had mutations of unknown significance, and one had a benign genetic variant. For the 15 patients with confirmed pathogenic variants of LDS the median follow-up duration was 5 years (interquartile range [IQR]: 4-8). Eleven patients underwent ascending aortic replacements (AAR) ± aortic valve replacement. Two patients required an additional operation; one required arch and staged elephant trunk for a dissection 18 years post-AAR and the other patient required an isolated descending aortic replacement for dissection 5 years post-AAR. Among patients who underwent surgery, the median ascending aortic diameter at intervention was 5.0 cm (IQR: 4.3-5.3). There was no surgical or late follow-up mortality observed for any of the 18 patients in the study.

CONCLUSION

LDS patients who underwent proximal aortic replacement appeared to have low long-term risk of arch complications. While our study is somewhat limited by its sample size and follow-up duration, it suggests that routine prophylactic total arch replacement may not be warranted in LDS patients with nonaneurysmal aortic arches.

Screening Tool to Identify Patients with Advanced Aortic Valve Stenosis

(1) Background: The clinical burden of aortic stenosis (AS) remains high in Western countries. Yet, there are no screening algorithms for this condition. We developed a risk prediction model to guide targeted screening for patients with AS. (2) Methods: We performed a cross-sectional analysis of all echocardiographic studies performed between 2013 and 2018 at a tertiary academic care center. We included reports of unique patients aged from 40 to 95 years. A logistic regression model was fitted for the risk of moderate and severe AS, with readily available demographics and comorbidity variables. Model performance was assessed by the C-index, and its calibration was judged by a calibration plot. (3) Results: Among the 38,788 reports yielded by inclusion criteria, there were 4200 (10.8%) patients with ≥moderate AS. The multivariable model demonstrated multiple variables to be associated with AS, including age, male gender, Caucasian race, Body Mass Index ≥ 30, and cardiovascular comorbidities and medications. C-statistics of the model was 0.77 and was well calibrated according to the calibration plot. An integer point system was developed to calculate the predicted risk of ≥moderate AS, which ranged from 0.0002 to 0.7711. The lower 20% of risk was approximately 0.15 (corresponds to a score of 252), while the upper 20% of risk was about 0.60 (corresponds to a score of 332 points). (4) Conclusions: We developed a risk prediction model to predict patients' risk of having ≥moderate AS based on demographic and clinical variables from a large population cohort. This tool may guide targeted screening for patients with advanced AS in the general population.

Right heart thrombi (RHT) and clot in transit with concomitant PE management: Approach and considerations

Right heart thrombi (RHT) continues to pose a clinical dilemma for multiple specialties and is especially concerning when present with concomitant pulmonary embolism (PE). Patients with PE and RHT are at an increased risk of poor outcomes compared to PE without RHT. Although the exact incidence of RHT is unknown, the increasing use of point-of-care ultrasound may lead to an increased detection and frequency of RHT. There are multiple treatment strategies available for RHT, including anticoagulation, systemic thrombolysis, and endovascular and surgical therapies. Given that these treatment strategies involve multiple medical specialties, the management of RHT with concomitant PE can be complex. Currently, there is limited clinical data and guidelines on the treatment and management of RHT. We aim to provide a review on RHT with concomitant PE, including risk stratification, treatment considerations, and our approach to the management of RHT.

mTOR inhibition prevents angiotensin II-induced aortic rupture and pseudoaneurysm but promotes dissection in Apoe-deficient mice

Aortic dissection and rupture are triggered by decreased vascular wall strength and/or increased mechanical loads. We investigated the role of mTOR signaling in aortopathy using a well-described model of angiotensin II–induced dissection, aneurysm, or rupture of the suprarenal abdominal aorta in Apoe-deficient mice. Although not widely appreciated, nonlethal hemorrhagic lesions present as pseudoaneurysms without significant dissection in this model. Angiotensin II–induced aortic tears result in free rupture, contained rupture with subadventitial hematoma (forming pseudoaneurysms), dilatation, or healing, while the media invariably thickens regardless of mural tears. Medial thickening results from smooth muscle cell hypertrophy and extracellular matrix accumulation, including matricellular proteins. Angiotensin II activates mTOR signaling in vascular wall cells, and inhibition of mTOR signaling by rapamycin prevents aortic rupture but promotes dissection. Decreased aortic rupture correlates with decreased inflammation and metalloproteinase expression, whereas extensive dissection correlates with induction of matricellular proteins that modulate adhesion of vascular cells. Thus, mTOR activation in vascular wall cells determines whether aortic tears progress to dissection or rupture. Previous mechanistic studies of aortic aneurysm and dissection by angiotensin II in Apoe-deficient mice should be reinterpreted as clinically relevant to pseudoaneurysms, and mTOR inhibition for aortic disease should be explored with caution.

Growth rate of ascending thoracic aortic aneurysms in a non-referral-based population

Background

Prior studies on ascending thoracic aortic aneurysm (ATAA) growth rates have reported approximately 1 mm of growth per year but these studies are based on referral-based study populations which are biased towards the highest risk patients who may not represent the true natural history of aortic aneurysm disease. We aimed to characterize the growth rate of ATAAs in a non-referral-based population, using a large institutional database of computed tomography (CT) scans.

Methods

We queried the 21,325 CT scans performed at our institution between 2013 and 2016 on patients ages 50–85 years old for radiologic diagnosis of aortic aneurysm or dilatation. 560 patients were identified to have aortic dilatation > 4 cm, of which 207 had follow-up scan intervals > 6 months. This comprised our non-referral-based study population. Linearized annual aneurysm growth rates were calculated by dividing the change in aortic size by the time interval between CT scans.

Results

The median time interval between scans was 2.7 years (interquartile range [IQR] 1.5–4.2) for the 207 patients included in the study. The median initial aneurysm size was 4.3 cm (IQR 4.1–4.5). 38.2% (n = 79) of patients did not experience aortic dilatation. The median growth rate was 0.13 mm/year (IQR − 0.24 to 0.49). Of patients in the top quartile of growth rates, 26.9% of patients were female whereas 12.9% of patients were female in the bottom three quartiles of growth rates.

Conclusion

While some patients’ ATAAs may grow at previously published rates of around 1 mm/year, this is not the predominant pattern in a non-referral-based population and may over-estimate the overall growth rate of ATAAs.

Combined Use of ECMO, Prone Positioning, and APRV in the Management of Severe COVID-19 Patients

Background

Severe COVID-19-associated Acute Respiratory Distress Syndrome (ARDS) may warrant extracorporeal membrane oxygenation (ECMO). We evaluated the safety and physiologic changes in oxygenation and hemodynamic profile during ECMO, prone positioning, and the two modalities combined in patients receiving veno-venous (VV) ECMO.

Methods

Cohort study of consecutive adult patients with COVID-19-associated ARDS requiring VV-ECMO, classified into three groups: ECMO support only; Prone positioning only; and Prone positioning during ECMO. We collected hemodynamic, respiratory and ventilation variables as follows: pre-treatment, 1, 6, and 24 h post-treatment, and documented treatment-related complications. On-treatment variables were compared with pre-treatment using one-sample paired t-test with Bonferroni correction.

Results

Fourteen patients (mean age 48.1 [SD 9.3] years, male [100%]) received VV-ECMO. Of those, 10 patients had data during prone positioning alone and seven had data while proned on ECMO. While on ECMO, patients had improvement in oxygen saturation, PaO₂/FiO₂ ratio, and minute ventilation up to 24 h post-treatment. Vasopressor requirements increased with ECMO at 1 h and 24 h post-treatment. Prone positioning was not associated with clinically significant hemodynamic or respiratory changes, either alone or during ECMO support. All patients sustained deep tissue injuries, but only those on the face or chest were related to prone positioning. Three patients required cannula replacement. In-hospital mortality was 43%.

Conclusions

VV-ECMO and prone positioning in patients with COVID-19 ARDS was overall well-tolerated; however, physiologic improvements were marginal, and patients sustained deep tissue injuries. Although this was a selected population with high mortality, our data call into question the benefits of these management modalities in this severe COVID-19 population.

Socioeconomic disparities in surveillance and follow-up of patients with thoracic aortic aneurysm

BACKGROUND

Thoracic aortic aneurysm (TAA) is a significant risk factor for aortic dissection and rupture. Guidelines recommend referral of patients to a cardiovascular specialist for periodic surveillance imaging with surgical intervention determined primarily by aneurysm size. We investigated the association between socioeconomic status (SES) and surveillance practices in patients with ascending aortic aneurysms.

METHODS

We retrospectively reviewed records of 465 consecutive patients diagnosed between 2013 and 2016 with ascending aortic aneurysm ≥4 cm on computed tomography scans. Primary outcomes were clinical follow-up with a cardiovascular specialist and aortic surveillance imaging within 2 years following index scan. We stratified patients into quartiles using the area deprivation index (ADI), a validated percentile measure of 17 variables characterizing SES at the census block group level. Competing risks analysis was used to determine interquartile differences in risk of death before follow up with a cardiovascular specialist.

RESULTS

Lower SES was associated with significantly lower rates of surveillance imaging and referral to a cardiovascular specialist. On competing risks regression, the ADI quartile with lowest SES had lower hazard of follow-up with a cardiologist or cardiac surgeon before death (hazard ratio: 0.46 [0.34, 0.62], p < .001). Though there were no differences in aneurysm size at time of surgical repair, patients in the lowest socioeconomic quartile were more frequently symptomatic at surgery than other quartiles (92% vs. 23%-38%, p < .001).

CONCLUSION

Patients with lower SES receive less timely follow-up imaging and specialist referral for TAAs, resulting in surgical intervention only when alarming symptoms are already present.

Changing the default option in electronic medical records reduced postoperative opioid prescriptions after cardiac surgery

Objective

Overprescribing of opioids has contributed to the opioid epidemic. Electronic medical records systems can auto-populate a default number of opioid pills that are prescribed at time of discharge. The aim of this study was to examine the association between lowered default pill counts with changed prescribing practices after cardiac surgery.

Methods

On May 18, 2017, the default number of pills prescribers see in electronic medical records in the Yale New Haven Health System was lowered from 30 to 12. Patients undergoing coronary artery grafts, valve surgeries, and thoracic aortic aneurysm surgeries were included in this study. Data were gathered and stratified into 2 groups: 1 year before and 1 year following the default change. The amount of opioid prescribed was compared between the 2 groups.

Results

A total of 1741 patient charts were reviewed, 832 before the change and 909 after the change. Significant changes were seen in prescribing practices, where the average amount of opioid prescribed was about 25% lower after the change. This amounted to about 15 fewer pills of 5 mg morphine for each patient. A linear regression model adjusting for other factors determined a prescribing difference of 75.2 morphine milligram equivalents per prescription (P < .01). In addition, a significant decrease in opioids prescribed was found for each type of procedure.

Conclusions

Lowering the default opioid pill count in electronic medical record systems is a simple intervention that may modify prescribing behavior to promote judicious prescribing of opioids after cardiac surgery.

Development and Validation of a Predictive Model to Identify Patients With an Ascending Thoracic Aortic Aneurysm

Background

Screening protocols do not exist for ascending thoracic aortic aneurysms (ATAAs). A risk prediction algorithm may aid targeted screening of patients with an undiagnosed ATAA to prevent aortic dissection. We aimed to develop and validate a risk model to identify those at increased risk of having an ATAA, based on readily available clinical information.

Methods and Results

This is a cross‐sectional study of computed tomography scans involving the chest at a tertiary care center on unique patients aged 50 to 85 years between 2013 and 2016. These criteria yielded 21 325 computed tomography scans. The double‐oblique technique was used to measure the ascending thoracic aorta, and an ATAA was defined as >40 mm in diameter. A logistic regression model was fitted for the risk of ATAA, with readily available demographics and comorbidity variables. Model performance was characterized by discrimination and calibration metrics via split‐sample testing. Among the 21 325 patients, there were 560 (2.6%) patients with an ATAA. The multivariable model demonstrated that older age, higher body surface area, history of arrhythmia, aortic valve disease, hypertension, and family history of aortic aneurysm were associated with increased risk of an ATAA, whereas female sex and diabetes were associated with a lower risk of an ATAA. The C statistic of the model was 0.723±0.016. The regression coefficients were transformed to scores that allow for point‐of‐care calculation of patients' risk.

Conclusions

We developed and internally validated a model to predict patients' risk of having an ATAA based on demographic and clinical characteristics. This algorithm may guide the targeted screening of an undiagnosed ATAA.