Graft flow evaluation with intraoperative transit-time flow measurement in off-pump versus on-pump coronary artery bypass grafting.

Objective: We aimed to compare transit-time flow measurement (TTFM) parameters for on-pump (ONCAB) and off-pump (OPCAB) coronary artery bypass procedures. Methods: The database of the Registry for Quality AssESsmenT with Ultrasound Imaging and TTFM in Cardiac Bypass Surgery (REQUEST) study was retrospectively reviewed. Only single grafts were included (ie, no sequential or Y/T grafts). Primary end points were mean graft flow (MGF), pulsatility index (PI), diastolic fraction (DF), and backflow (BF). Unadjusted and propensity score-matching comparisons were performed. Results: Of 1016 patients in the REQUEST registry, 846 had at least 1 graft for which TTFM was performed. Of these, 512 patients (60.6%) underwent ONCAB and 334 (39.4%) OPCAB procedures. Mean arterial pressure (MAP) during measurements was higher in the OPCAB group. After propensity score-matching, 312 well balanced pairs were left. In these matched patients, MGF was higher for the ONCAB versus the OPCAB group (32 vs 28 mL/min, respectively, for all grafts [P < .001]; 30 vs 27 mL/min for arterial grafts [P = .002]; and 35 vs 31 mL/min for venous grafts [P = .006], respectively). PI was lower in the ONCAB group (2.1 vs 2.3, for all grafts; P < .001). Diastolic fraction was slightly lower in the ONCAB group (65% vs 67.5%; P < .001). The backflow was also lower in the ONCAB group (0.6 vs 1.3; P < .001) with trends similar to MGF and PI for venous and arterial grafts. There were 21 (3.3%) revisions in the OPCAB group and 14 (2.1%) in the ONCAB group (P = .198). Conclusions: ONCAB surgery was associated with higher MGF and lower PI values, especially in venous grafts. Different TTFM cutoff values for ONCAB versus OPCAB surgery might be considered.

Pulmonary Endarterectomy for Chronic Thromboembolic Pulmonary Hypertension: An STS Database Analysis.

BACKGROUND: Chronic thromboembolic pulmonary hypertension is optimally treated by pulmonary thromboendarterectomy (PEA). Treatment effectiveness has been evaluated principally using single-center series. Data from The Society of Thoracic Surgeons Adult Cardiac Surgery Database were used to evaluate a volume-outcomes relationship for PEA. METHODS: Circulatory arrest procedures performed between 2012 and 2018 were identified through a Society of Thoracic Surgeons Adult Cardiac Surgery Database Participant User File. For descriptive purposes, total center procedural volume categories were computed: low (0-75th percentile, <16); medium (76-95th percentile, 16-100); high (>95th percentile, >100). Mixed effect modeling was used to evaluate the effect of center procedural volume (modeled continuously) on operative mortality, adjusting for preoperative risk factors, with centers as a random effect. RESULTS: There were 1358 cases performed across 64 centers (low volume: n = 49 of 172; medium volume: n = 12 of 527; high volume: n = 3 of 659), with 42 centers performing less than 10 operations during the period. Procedural volume increased 2.6-fold between 2012 and 2018 (94 vs 339), with 79% of the change in volume accounted for by 4 centers. The median preoperative pulmonary artery systolic value was 74 (interquartile range, 57-88) mm Hg, with no difference (P = .55) by center volume categories. In unadjusted analysis, patients at high-volume centers required fewer transfusions, had shorter ventilator and intensive care unit duration, had a lower frequency of postoperative extracorporeal membrane oxygenation, and trended toward lower mortality (2.1% vs 5.2%; P = .051). Operative mortality was lower at higher-volume centers (adjusted odds ratio [1-case increase], 0.997; 95% confidence interval, 0.994-1.0; P = .025). CONCLUSIONS: Most PEA procedures are performed among a small number of centers, with high-volume hospitals having favorable outcomes. These data suggest a potential role for PEA regionalization.

Stentectomy for LAD "full metal jacket" with in-stent restenosis: How to do it.

We report our technique for the surgical revascularization of symptomatic severe in-stent restenosis of a "full metal jacket" (≥60 mm overlapping stents) of the left anterior descending coronary artery without suitable distal targets: on-pump cardioplegic-arrest stent removal (stentectomy) with endarterectomy and skeletonized left internal mammary artery onlay patch reconstruction. We also describe our follow-up protocol, including antiplatelet/anticoagulation and angiography. With proper patient selection, multidisciplinary collaboration, and surgical expertise, this advanced coronary procedure can be beneficial to a growing population of patients otherwise deemed to be untreatable.

Transit time flow measurement of coronary bypass grafts before and after protamine administration.

BACKGROUND: Intraoperative graft assessment with tools like Transit Time Flow Measurement (TTFM) is imperative for quality control in coronary surgery. We investigated the variation of TTFM parameters before and after protamine administration to identify new benchmark parameters for graft quality assessment. METHODS: The database of the REQUEST ("REgistry for QUality AssESsmenT with Ultrasound Imaging and TTFM in Cardiac Bypass Surgery") study was retrospectively reviewed. A per graft analysis was performed. Only single grafts (i.e., no sequential nor composite grafts) where both pre- and post-protamine TTFM values were recorded with an acoustical coupling index > 30% were included. Grafts with incomplete data and mixed grafts (arterio-venous) were excluded. A second analysis was performed including single grafts only in the same MAP range pre- and post- protamine administration. RESULTS: After adjusting for MAP, we found a small increase in MGF (29 mL/min to 30 mL/min, p = 0.009) and decrease in PI (2.3 to 2.2, p <  0.001) were observed after the administration of protamine. These changes were especially notable for venous conduits and for CABG procedures performed on-pump. CONCLUSION: The small changes in TTFM parameters observed before and after protamine administration seem to be clinically irrelevant, despite being statistically significant in aggregate. Our data do not support a need to perform TTFM measurements both before and after protamine administration. A single TTFM measurement taken either before or after protamine may suffice to achieve reliable data on each graft's performance. Depending on the specific clinical situation and intraoperative changes, more measurements may be informative. TRIAL REGISTRATION: Clinical Trials Number: NCT02385344 , registered February 17th, 2015.

Smart Node Networks Orchestration: A New E2E Approach for Analysis and Design for Agile 4.0 Implementation.

The field of cyber-physical systems is a growing IT research area that addresses the deep integration of computing, communication and process control, possibly with humans in the loop. The goal of such area is to define modelling, controlling and programming methodologies for designing and managing complex mechatronics systems, also called industrial agents. Our research topic mainly focuses on the area of data mining and analysis by means of multi-agent orchestration of intelligent sensor nodes using internet protocols, providing also web-based HMI visualizations for data interpretability and analysis. Thanks to the rapid spreading of IoT systems, supported by modern and efficient telecommunication infrastructures and new decentralized control paradigms, the field of service-oriented programming finds new application in wireless sensor networks and microservices paradigm: we adopted such paradigm in the implementation of two different industrial use cases. Indeed, we expect a concrete and deep use of such technologies with 5G spreading. In the article, we describe the common software architectural pattern in IoT applications we used for the distributed smart sensors, providing also design and implementation details. In the use case section, the prototypes developed as proof of concept and the KPIs used for the system validation are described to provide a concrete solution overview.

Surgical explantation of transcatheter aortic bioprostheses: Results and clinical implications.

OBJECTIVE: Despite the rapid adoption of transcatheter aortic valve replacement (TAVR) and worldwide interest in its implantation, TAVR valve explantation has not been well described. METHODS: We retrospectively reviewed 1442 consecutive patients who underwent a TAVR procedure between 2011 and 2019, in which TAVR explantation was performed in 15 patients (1.0%). In addition, 2 patients from outside institutions also underwent TAVR explantation at our institution. We reviewed the clinical details of these 17 patients. RESULTS: The frequency of TAVR explant increased over time from 0 to 1 during the period from 2011 to 2015 to 6 in 2019. The mean age was 73.0 ± 9.3 years. The majority of patients (88.2%) were in New York Heart Association functional class IV heart failure. The Society of Thoracic Surgeons Predicted Risk of Mortality score was significantly higher at the time of explantation than at the time of the original TAVR (3.5% vs 9.9%; P < .001). The indication for explantation included structural valve degeneration (23.5%), severe paravalvular leak (41.2%), TAVR procedure-related complications (23.5%), endocarditis (5.9%), and bridge-to-definitive surgery (5.9%). Neoendothelialization of the TAVR valve into the aortic wall requiring intense aortic endarterectomy was noted in all 5 of the TAVR valves older than 1 year, in which 2 (40%) required unplanned aortic root repair. There were 2 (11.8%) in-hospital mortalities. CONCLUSIONS: Surgical TAVR valve explant is increasing and may become common in the near future. The clinical effects of explanting chronically implanted valves with the potential need for aortic repair is not negligible. These data should be used to more appropriately select TAVR candidates as TAVR practices expand into younger and lower risk patients.

Acute Type A Aortic Dissection During the COVID-19 Outbreak.

As of April 7, 2020, approximately 1,300,000 cases and 80,000 deaths related to coronavirus disease 2019 (COVID-19) have been reported in more than 180 countries/territories. Health care infrastructures and resources, particularly as it relates to the care of the most critically ill patients, are currently being strained globally. In this context, however, there has been little clinical guidance or information regarding life-threatening conditions requiring emergency operation that cannot be delayed. We present a case of acute type A aortic dissection in a patient with COVID-19 to highlight the clinical implications of a true emergent procedure during the COVID-19 outbreak.

Is previous cardiac surgery a risk factor for open repair of acute type A aortic dissection?

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