This paper focuses on a range of ethical issues related to pandemics, especially allocation of scarce resources (ventilators, ECMO).

Background: Methylene blue (MB) has been used to treat refractory hypotension in a variety of settings. Aims: We sought to determine whether MB improved blood pressure in postcardiopulmonary bypass (CPB) vasoplegic syndrome (VS) in a complex cardiac surgery population. Furthermore, to determine variables that predicted response to MB. Setting and Design: This was conducted in a tertiary care medical center; this study was a retrospective cohort study. Materials and Methods: Adult cardiac surgery patients who received MB for post-CPB VS over a 2-year period were studied. Mean arterial blood pressure (MAP) and vasopressor doses were compared before and after MB, and logistic regression was used to model which variables predicted response. Results: Eighty-eight patients received MB for post-CPB VS during the study period. MB administration was associated with an 8 mmHg increase in MAP (P = 0.004), and peak response occurred at 2 h. Variables that were associated with a positive drug response were deep hypothermic circulatory arrest during surgery and higher MAP at the time of drug administration (P = 0.006 and 0.02). A positive response had no correlation with in-hospital mortality (P = 0.09). Conclusions: MB modestly increases MAP in cardiac surgery patients with VS. Higher MAP at the time of drug administration and surgery with deep hypothermic circulatory arrest predict a greater drug response.

This case presents a patient who underwent aortic valve replacement and presented 13 years later with high gradients across the prosthesis, mitral insufficiency, and severe systemic hypertension. Her preoperative workup led to the diagnosis of an interrupted aortic arch Type A. Her surgical management included an initial procedure to repair the interruption, and 11 months later after resolution of her hypertension, a second surgery, which included the Ross procedure and mitral valve repair.

Introduction Recognizing the importance of neuroprotection in aortic arch surgery, deep hypothermic circulatory arrest (DHCA) now underpins operative practice as it minimizes cerebral metabolic activity. When prolonged periods of circulatory arrest are required, selective antegrade cerebral perfusion (SACP) is supplemented as an adjunct. However, concerns exist over the risks of SACP in introducing embolism and hypo- and hyper-perfusing the brain. The present meta-analysis aims to compare postoperative outcomes in arch surgery using DHCA alone or DHCA + SACP as neuroprotection strategies. Methods Electronic searches were performed using six databases from their inception to January 2013. Two reviewers independently identified all relevant studies comparing DHCA alone with DHCA + SACP. Data were extracted and meta-analyzed according to pre-defined clinical endpoints. Results Nine comparative studies were identified in the present meta-analysis, with 648 patients employing DHCA alone and 370 utilizing DHCA + SACP. No significant differences in temporary or permanent neurological outcomes were identified. DHCA + SACP was associated with significantly better survival outcomes (P=0.008, I2=0%), despite longer cardiopulmonary bypass time. Infrequent and inconsistent reporting of other clinical results precluded analysis of systemic outcomes. Conclusions The present meta-analysis indicate the superiority of DHCA + SACP in terms of mortality outcomes.

Accurate identification of in vivo nonlinear, anisotropic mechanical properties of the aortic wall of individual patients remains to be one of the critical challenges in the field of cardiovascular biomechanics. Since only the physiologically loaded states of the aorta are given from in vivo clinical images, inverse approaches, which take into account of the unloaded configuration, are needed for in vivo material parameter identification. Existing inverse methods are computationally expensive, which take days to weeks to complete for a single patient, inhibiting fast feedback for clinicians. Moreover, the current inverse methods have only been evaluated using synthetic data. In this study, we improved our recently developed multi-resolution direct search (MRDS) approach and the computation time cost was reduced to 1~2 hours. Using the improved MRDS approach, we estimated in vivo aortic tissue elastic properties of two ascending thoracic aortic aneurysm (ATAA) patients from pre-operative gated CT scans. For comparison, corresponding surgically-resected aortic wall tissue samples were obtained and subjected to planar biaxial tests. Relatively close matches were achieved for the in vivo-identified and ex vivo-fitted stress-stretch responses. It is hoped that further development of this inverse approach can enable an accurate identification of the in vivo material parameters from in vivo image data.

Objective: Controversy exists about the optimal treatment of acute uncomplicated type B aortic dissection (auTBAD). Optimal medical therapy (OMT) provides excellent short-term outcomes, but long-term results are poor. Ideally, auTBAD patients who will fail to respond to OMT in the chronic phase could be identified and undergo thoracic endovascular aortic repair. The purpose of this study was to identify radiographic predictors of auTBAD patients who will fail to respond to OMT. Methods: A review of the Emory aortic database from 2000 to 2017 identified 320 auTBAD patients initially treated with OMT. From this cohort, 121 patients with two or more contrast-enhanced imaging scans were available for analysis. These patients were initially divided into groups based on growth of the thoracic aorta ≥10 mm or intervention due to aneurysmal growth: growth (n = 72) and no growth (n = 49). TeraRecon (Foster City, Calif) imaging software was used to analyze characteristics of the primary intimal tear (PIT), false lumen, and overall aortic size. Finally, Cox proportional hazards models were constructed to estimate hazard ratios and to identify predictors of OMT failure. Results: The mean age of all patients was 54 ± 11 years, and 67% were male. Thirty-eight patients (53%) in the growth group underwent intervention. There were no differences between groups in age, hypertension, diabetes mellitus, tobacco abuse, or chronic obstructive pulmonary disease. The distance of the PIT from the left subclavian artery in patients with auTBAD was significantly shorter in the growth group (growth, 27 mm [9-66 mm]; no growth, 77 mm [26-142 mm]; P <.01). Multivariable Cox regression analysis identified the distance of the PIT from the left subclavian artery and a thoracic aortic diameter >45 mm as independent predictors of failure of OMT. Partial false lumen thrombosis was not a predictor of aortic growth. Conclusions: The distance of the PIT from the left subclavian artery is a predictor of aortic growth in auTBAD. Patients with a primary tear located in zone 3 of the proximal descending thoracic aorta should be monitored closely and may be considered for early thoracic endovascular aortic repair in the setting of auTBAD.

Background: Valve-sparing root replacement is more challenging with eccentric aortic insufficiency due to cusp and root asymmetry, which may impact valve durability and survival. This study analyzed the effect of jet eccentricity on long-term outcomes in tricuspid aortic valves (TAVs) and bicuspid aortic valves (BAVs). Methods: From 2005 to 2019, 111 patients (65 TAVs, 46 BAVs) with >2+ aortic insufficiency underwent valve-sparing root replacement at an academic center. Pre- and postoperative echocardiograms were analyzed. Of these, 32 patients presented with concentric jets (29 TAVs, 3 BAVs) and 71 with eccentric jets (28 TAVs, 43 BAVs). Median follow-up was 49 months (interquartile range, 12-93). Kaplan-Meier analysis and cumulative risk were used to compare long-term survival and valve-related reintervention. Results: Mean patient age was 44 ± 12 years. Compared with TAV, more BAV patients presented with eccentric jets (93.5% vs 43.1%, P <.001). All BAV patients received cusp repair compared with 52.3% of TAV patients (P <.001). At 3, 5, and 10 years the cumulative risk of aortic valve replacement for TAV (4.7%, 6.4%, and 6.4%) versus BAV (5.8%, 7.8%, and 7.8%) patients (P =.87) and concentric (0%, 0%, and 0%) versus eccentric (6.4%, 9.4%, and 9.4%) jets (P =.98) was similar. Overall survival at 10 years was 71% for TAV and 97% for BAV (P =.19) and 86% for concentric and 79% for eccentric jets (P =.17). Conclusions: In patients presenting for valve-sparing root replacement with >2+ aortic insufficiency the risk of valve-related reintervention long term was low after cusp repair in TAVs and BAVs. Current results suggest preoperative jet eccentricity does not impact long-term survival and valve durability.

The David V valve-sparing root replacement (VSRR) is well-established for the treatment of aortic insufficiency (AI) and advanced root aortopathy. The impact of cusp repair in trileaflet aortic valve (TAV) patients, however, with preoperative moderate-severe AI and an eccentric jet is unclear. This study compares outcomes in TAV patients with pre-operative AI >2+ based on jet centricity and cusp repair status. Review of a single institutional database identified 309 consecutive patients undergoing VSRR from 2005 to 2018. Of these, 51 patients had TAV with AI >2+: 25 concentric and 26 eccentric jets. Mean follow-up was 58 (SD = 44) months. Echocardiographic parameters were compared pre- and post-operatively. Kaplan-Meier analysis, longitudinal mixed modeling, and cumulative incidence were used to compare long-term survival, recurrence of AI >1+, and valve specific re-intervention, respectively. The mean age was 48 (SD = 12) years and 84% were male. Differences in preoperative comorbidities and echocardiographic parameters between groups were not statistically significant. Postoperative outcomes were similar in concentric vs. eccentric and cusp vs. no cusp repair. Recurrence of AI>1+ was minimal and unrelated to jet centricity (concentric = 1, eccentric = 3) and cusp repair (no cusp repair = 1, cusp repair = 3) long-term. Aortic valve replacement cumulative incidence was 0% for central and 5% for eccentric at 3-, 5-, and 10-years, respectively. Long-term mortality was similar regardless of jet centricity and cusp repair. In appropriately selected TAV patients with preoperative AI >2+, current results suggest VSRR provides a durable repair regardless of jet centricity or the need for cusp repair based on low rates of reintervention reported.

Naganuma and colleagues1 present a unique and novel technique to mitigate spinal cord injury (SPI) using nanobubble technology to oxygenate cerebrospinal fluid (CSF), administered via intrathecal microcatheter infusion. Using a validated rabbit model of SCI involving 15 minutes of infrarenal aorta occlusion, animals were assigned to 1 of 4 groups: (1) sham procedure group (n = 5), with microcatheter placement and 5 seconds of aortic occlusion; (2) ischemia only group (n = 5), with microcatheter placement and 15 minutes of aortic occlusion; (3) nonoxygenated ischemia group (n = 5), with 15 minutes of aortic occlusion followed by microcatheter infusion of nonoxygenated CSF; and (4) oxygenated ischemia group (n = 5), with 15 minutes of aortic occlusion followed by microcatheter infusion of oxygenated CSF. Artificial CSF infusion was initiated 15 minutes after aortic occlusion and lasted 60 minutes. Partial pressure of oxygen in CSF (CSF-PO2) was assessed during the procedure. At 48 hours, a neurologic evaluation was performed for hind limb function, and the animals were euthanized for histological spinal cord analysis by a blinded pathologist.

UNLABELLED: Catecholamines and vasopressin are commonly used in patients with post cardiovascular surgery vasoplegia (PCSV). Multimodal therapy, including methylene blue (MB), hydroxocobalamin, and angiotensin II (Ang II), may improve outcomes in patients who remain hypotensive despite catecholamine and vasopressin therapy. However, a standardized approach has not been established. We created a protocol at Emory Healthcare (Emory Protocol), which provides guidance on norepinephrine equivalent dose (NED) and the use of noncatecholamines in the setting of PCSV and sought to determine the clinical significance of adherence to the protocol. DESIGN: Retrospective study. SETTING: Multisite study at Emory University Hospital. PATIENTS: Patients receiving Ang II for PCSV in any cardiovascular ICU from 2018 to 2020. INTERVENTIONS: Patient encounters were scored on Emory Protocol compliance based on NED (1-5), use of vasopressin (1-2), use of MB (1-2), and documentation of high-output shock (1-4). A compliant score was less than 7, moderately compliant 7 to 8, and poorly compliant greater than 8. Demographics, clinical data, and outcomes were abstracted from the medical records. MEASUREMENTS AND MAIN RESULTS: Of the 78 consecutive patients receiving Ang II for PCSV, overall ICU mortality was 26.9%, with an average compliance score of 6.2. ICU mortality was 21.1% for compliant cases (n = 38), 29.7% for moderately compliant cases (n = 24), and 37.5% for poorly compliant cases (n = 16). In regression analysis, the cumulative compliance score to the Emory Protocol was predictive of ICU mortality (p = 0.027). CONCLUSIONS: Compliance with the Emory Protocol, emphasizing early initiation of the noncatecholamines vasopressin, MB, hydroxocobalamin, and Ang II at lower catecholamine doses in high-output shock, is associated with improved ICU mortality.