Four decades of progress in heart-lung transplantation: Two hundred seventy-one cases at a single institution.

OBJECTIVE: The objective of this study is to evaluate survival for combined heart-lung transplant (HLTx) recipients across 4 decades at a single institution. We aim to summarize our contemporary practice based on more than 271 HLTx procedures over 40 years. METHODS: Data were collected from a departmental database and the United Network for Organ Sharing. Recipients younger than age 18 years, those undergoing redo HLTx, or triple-organ system transplantation were excluded, leaving 271 patients for analysis. The pioneering era was defined by date of transplant between 1981 and 2000 (n = 155), and the modern era between 2001 and 2022 (n = 116). Survival analysis was performed using cardinality matching of populations based on donor and recipient age, donor and recipient sex, ischemic time, and sex matching. RESULTS: Between 1981 and 2022, 271 HLTx were performed at a single institution. Recipients in the modern era were older (age 42 vs 34 y; P < .001) and had shorter waitlist times (78 vs 234 days; P < .001). Allografts from female donors were more common in the modern era (59% vs 39%; P = .002). In the matched survival analysis, 30-day survival (97% vs 84%; P = .005), 1-year survival (89% vs 77%; P = .041), and 10-year survival (53% vs 26%; P = .012) significantly improved in the modern era relative to the pioneering era, respectively. CONCLUSIONS: Long-term survival in HLTx is achievable with institutional experience and may continue to improve in the coming decades. Advances in mechanical circulatory support, improved maintenance immunosuppression, and early recognition and management of acute complications such as primary graft dysfunction and acute rejection have dramatically improved the prognosis for recipients of HLTx in our contemporary institutional experience.

Outcomes of Patients Undergoing Combined Heart-Kidney Transplantation With or Without Prior Ventricular Assist Device.

BACKGROUND: Both combined heart-kidney transplantation and ventricular assist devices (VADs) pose significant challenges, including sensitization, immunosuppressive treatment, and infrastructure demands. Despite these challenges, we hypothesized that the recipients of combined heart-kidney transplants with and without VADs would have equivalent survival. We aimed to compare the survival of heart-kidney transplant recipients with and without prior VAD placement. METHODS: We retrospectively analyzed all patients enrolled in the United Network for Organ Sharing database who underwent heart-kidney transplants. We created a matched cohort of patients undergoing heart-kidney transplantation with or without prior VAD using 1:1 nearest propensity-score matching with preoperative variables. RESULTS: In the propensity-matched cohort, 399 patients underwent heart-kidney transplantation with prior VAD, and 399 underwent heart-kidney transplantation without prior VAD. The estimated survival of heart--kidney recipients with prior VAD was 84.8% at one year, 81.2% at 3 years, and 75.3% at 5 years. The estimated survival of heart-kidney recipients without prior VAD was 86.8.7% at one year, 84.0% at 3 years, and 78.8% at 5 years. There was no statistically significant difference in the survival of heart-kidney transplant recipients with or without prior VAD at one year (P = .42; Figure 2), 3 years (P = .34), or 5 years (P = .30). CONCLUSION: Despite the increased challenge of heart-kidney transplantation in recipients with prior VAD, we demonstrated that these patients have similar survival to those who underwent heart-kidney transplantation without previous VAD placement.

Controlled balloon false lumen obliteration for the endovascular management of chronic dissection in the descending thoracic aorta.

Objective: Retrograde false lumen perfusion has limited the utility of aortic stent grafting for chronic aortic dissection. It is unknown whether balloon septal rupture can improve the outcomes for endovascular management of chronic aortic dissection. Methods: Included patients underwent false lumen obliteration and creation of a single-lumen aortic landing zone using balloon aortoplasty during thoracic endovascular aortic repair. The distal thoracic stent graft was sized to the total aortic lumen diameter, and septal rupture was performed within the stent graft with a compliant balloon in the region 5 cm proximal to the distal fabric edge. Clinical and radiographic outcomes are reported. Results: Forty patients, with an average age 56 years, underwent thoracic endovascular aortic repair with septal rupture. Seventeen patients (43%) had chronic type B dissections, 17 of 40 patients (43%) had residual type A dissections, and 6 of 40 patients (15%) had acute type B dissections. Nine cases were emergency, complicated by rupture or malperfusion. Perioperative complications included 1 death (2.5%) due to rupture of the descending thoracic aorta and 2 (5%) instances each of stroke (neither permanent) and spinal cord ischemia (1 permanent). Two (5%) stent graft-induced new injuries were seen. Average postoperative computed tomography follow-up was 1.4 years. Thirteen patients (33%) had a decrease in aortic size, 25 of 39 patients (64%) were stable, and 1 of 39 patients (2.6%) had an increased aortic size. Partial and complete false lumen thrombosis were achieved in 10 of 39 patients (26%) and 29 of 39 patients (74%), respectively. Midterm aortic-related survival was 97.5% at an average of 1.6 years. Conclusions: Controlled balloon septal rupture offers an effective endovascular method to treat aortic dissection in the distal thoracic aorta.

Surgical Management of Esophageal Perforation: Examining Trends in a Multi-Institutional Cohort.

BACKGROUND: Esophageal perforations historically are associated with significant morbidity and mortality and generally require emergent intervention. The influence of improved diagnostic and therapeutic modalities available in recent years on management has not been examined. This study examined the surgical treatments and outcomes of a modern cohort. METHODS: Patients with esophageal perforation management in the 2005-2020 American College of Surgeons National Surgical Quality Improvement Program database were stratified into three eras (2005-2009, 2010-2014, and 2015-2020). Surgical management was classified as primary repair, resection, diversion, or drainage alone based on procedure codes. The distribution of procedure use, morbidity, and mortality across eras was examined. RESULTS: Surgical management of 378 identified patients was primary repair (n=193,51%), drainage (n=89,24%), resection (n=70,18%), and diversion (n=26,7%). Thirty-day mortality in the cohort was 9.5% (n=36/378) and 268 patients (71%) had at least one complication. The median length of stay was 15 days. Both morbidity (Era 1 65% [n=42/60] versus Era 2 69% [n=92/131] versus Era 3 72% [n=135/187], p=0.3) and mortality (Era 1 11% [n=7/65] versus Era 2 9% [n=12/131] versus Era 3 10% [n=19/187], p=0.9) did not change significantly over the three defined eras. Treatment over time evolved such that primary repair was more frequently utilized (43% in Era 1 to 51% in Era 3) while diversion was less often performed (13% in Era 1 to 7% in Era 3) (p=0.009). CONCLUSIONS: Esophageal perforation management in recent years uses diversion less often but remains associated with significant morbidity and mortality.

Lineage-Specific Induced Pluripotent Stem Cell-Derived Smooth Muscle Cell Modeling Predicts Integrin Alpha-V Antagonism Reduces Aortic Root Aneurysm Formation in Marfan Syndrome Mice.

BACKGROUND: The role of increased smooth muscle cell (SMC) integrin αv signaling in Marfan syndrome (MFS) aortic aneurysm remains unclear. Herein, we examine the mechanism and potential efficacy of integrin αv blockade as a therapeutic strategy to reduce aneurysm progression in MFS. METHODS: Induced pluripotent stem cells (iPSCs) were differentiated into aortic SMCs of the second heart field (SHF) and neural crest (NC) lineages, enabling in vitro modeling of MFS thoracic aortic aneurysms. The pathological role of integrin αv during aneurysm formation was confirmed by blockade of integrin αv with GLPG0187 in Fbn1C1039G/+ MFS mice. RESULTS: iPSC-derived MFS SHF SMCs overexpress integrin αv relative to MFS NC and healthy control SHF cells. Furthermore, integrin αv downstream targets (FAK [focal adhesion kinase]/AktThr308/mTORC1 [mechanistic target of rapamycin complex 1]) were activated, especially in MFS SHF. Treatment of MFS SHF SMCs with GLPG0187 reduced p-FAK/p-AktThr308/mTORC1 activity back to control SHF levels. Functionally, MFS SHF SMCs had increased proliferation and migration compared to MFS NC SMCs and control SMCs, which normalized with GLPG0187 treatment. In the Fbn1C1039G/+ MFS mouse model, integrin αv, p-AktThr308, and downstream targets of mTORC1 proteins were elevated in the aortic root/ascending segment compared to littermate wild-type control. Mice treated with GLPG0187 (age 6-14 weeks) had reduced aneurysm growth, elastin fragmentation, and reduction of the FAK/AktThr308/mTORC1 pathway. GLPG0187 treatment reduced the amount and severity of SMC modulation assessed by single-cell RNA sequencing. CONCLUSIONS: The integrin αv-FAK-AktThr308 signaling pathway is activated in iPSC SMCs from MFS patients, specifically from the SHF lineage. Mechanistically, this signaling pathway promotes SMC proliferation and migration in vitro. As biological proof of concept, GLPG0187 treatment slowed aneurysm growth and p-AktThr308 signaling in Fbn1C1039G/+ mice. Integrin αv blockade via GLPG0187 may be a promising therapeutic approach to inhibit MFS aneurysmal growth.

Midterm Outcomes in Type A Aortic Dissection Repair With and Without Malperfusion in a Hybrid Operating Room.

Treatment approach to type A aortic dissection with malperfusion, immediate open aortic repair vs upfront endovascular treatment, remains controversial. From January 2017 to July 2021, 301 consecutive type A repairs were evaluated at our institution. Starting in 2019, all type A aortic dissections were performed in a fixed-fluoroscopy, hybrid operating room. Propensity score matching was used to control baseline patient characteristics between traditional and hybrid operating room approaches. There were 144 patients in the traditional group and 157 in the hybrid group. In the hybrid group, 41% (64/157) underwent intraoperative angiograms, and of those, 58% (37/64) received at least 1 endovascular intervention. Following propensity matching, 125 patients remained in each the traditional and hybrid groups. Thirty-day survival was significantly improved in the hybrid cohort at 96.7% (122/125) as compared to the traditional cohort at 87.2% (109/125) (P = 0.002). There were no significant differences in perioperative paralysis (1.6% vs 1.6%, P > 0.9), new hemodialysis (12% vs 9.6%, P = 0.5), fasciotomy (2.4% vs 5.6%, P = 0.20, and exploratory laparotomy (1.6% vs 4.8%, P = 0.3). The hybrid operating room approach to type A aortic dissection, provides the ability to immediately assess distal malperfusion and perform endovascular interventions at the time of open aortic repair, and is associated with significantly higher 30-day and 2-year survival when compared to a stepwise repair approach in a traditional operating room.

Combined Heart-Lung Transplantation Outcomes in Asian Populations: National Database Analysis.

Background: Heart-lung transplantation (HLTx) is a definitive surgical procedure for end-stage cardiopulmonary failure. Studies to understand the relationship between ethnicity and race and outcomes after HLTx are needed to uphold equitable HLTx access to the increasingly diverse U.S. population facing advanced cardiopulmonary failure. Objectives: This study sought to examine the outcomes of HLTx recipients of Asian origin, with emphasis on the ethnic and racial disparities in the outcomes. Methods: We analyzed data from the United Network for Organ Sharing (UNOS) for patients of ≥18 years of age who underwent HLTx between 1987 and 2021. Propensity-score matching was performed between Asian and non-Hispanic Whites (NHWs), with a 1:3 matching ratio based on the propensity score of each patient estimated by multivariable logistic regression. Results: We identified 42 Asian and Asian American heart-lung transplant recipients and 834 NHW recipients. In the pre-matched cohort, the median survival was 1,459 days (IQR: 1,080-2,692 days) in Asian recipients after transplantation, whereas it was 1,521 days (IQR: 1,262-1,841 days) in White recipients. Of the 876 recipients, 156 transplants were successfully matched (Asian, n = 36; NHW, n = 108). Among the post-transplantation outcomes, there were no significant differences in morbidity and mortality between Asian and NHW cohorts. Conclusions: This large-scale analysis in Asian patients will have important implications in Asian countries that have relatively fewer HLTx surgeries. An outcome equivalent to NHW in Asian patients, as demonstrated in our study, could be the driving force for further expansion of HLTx surgeries in Asian countries.

Biomechanical engineering analysis of an acute papillary muscle rupture disease model using an innovative 3D-printed left heart simulator.

OBJECTIVES: The severity of acute papillary muscle (PM) rupture varies according to the extent and site of the rupture. However, the haemodynamic effects of different rupture variations are still poorly understood. Using a novel ex vivo model, we sought to study acute PM rupture to improve clinical management. METHODS: Using porcine mitral valves (n = 32) mounted within an ex vivo left heart simulator, PM rupture was simulated. The mitral valve was divided into quadrants for analysis according to the PM heads. Acute PM rupture was simulated by incrementally cutting from 1/3 to the total number of chordae arising from 1 PM head of interest. Haemodynamic parameters were measured. RESULTS: Rupture >2/3 of the chordae from 1 given PM head or regurgitation fraction >60% led to markedly deteriorated haemodynamics. Rupture at the anterolateral PM had a stronger negative effect on haemodynamics than rupture at the posteromedial PM. Rupture occurring at the anterior head of the anterolateral PM led to more marked haemodynamic instability than rupture occurring at the other PM heads. CONCLUSIONS: The haemodynamic effects of acute PM rupture vary considerably according to the site and extent of the rupture. Rupture of ≤2/3 of chordae from 1 PM head or rupture at the posteromedial PM lead to less marked haemodynamics effects, suggesting a higher likelihood of tolerating surgery. Rupture at the anterolateral PM, specifically the anterior head, rupture of >2/3 of chordae from 1 PM head or regurgitation fraction >60% led to marked haemodynamic instability, suggesting the potential benefit from bridging strategies prior to surgery.

Early Discharge After Lobectomy for Lung Cancer Does Not Equate to Early Readmission.

BACKGROUND: Enhanced recovery after surgery pathways in several specialties reduce length of stay, but accelerated discharge after thoracic surgery is not well characterized. This study tested the hypothesis that patients discharged on postoperative day 1 (POD1) after lobectomy for lung cancer have an increased risk of readmission. METHODS: Patients who underwent a lobectomy for lung cancer between 2011 and 2019 in the American College of Surgeons National Surgical Quality Improvement Program database were identified. Readmission rates were compared between patients discharged on postoperative day 1 (POD 1) and patients discharged on POD 2 to 6. Early discharge and readmission predictors were evaluated using multivariable logistic regression analysis. RESULTS: Only 854 (3.8%) of 22,585 patients who met inclusion criteria were discharged on POD 1, although POD 1 discharge rates increased from 2.3% to 8.1% (P < .001) from 2011 to 2019, respectively. Median hospitalization for patients discharged on POD 2 to 6 was 4 days (interquartile range, 3 to 5 days). Patients' characteristics associated with a lower likelihood of POD 1 discharge were increasing age, smoking, or a history of dyspnea, whereas a minimally invasive approach was the strongest predictor of early discharge (adjusted odds ratio, 5.42; P < .001). Readmission rates were not significantly different for the POD 1 and POD 2 to 6 groups in univariate analysis (6.0% vs 7.0%; P = .269). Further, POD 1 discharge was not a risk factor for readmission in multivariable analysis (adjusted odds ratio, 1.10; P = .537). CONCLUSIONS: Select patients can be discharged on POD 1 after lobectomy for lung cancer without an increased readmission risk, a finding supporting this accelerated discharge target inclusion in lobectomy enhanced recovery after surgery protocols.

Impact of Clot Shape on Successful M1 Endovascular Reperfusion.

Objectives: The susceptibility-vessel-sign (SVS) allows thrombus visualization, length estimation and composition, and it may impact reperfusion during mechanical thrombectomy (MT). SVS can also describe thrombus shape in the occluded artery: in the straight M1-segment (S-shaped), or in an angulated/traversing a bifurcation segment (A-shaped). We determined whether SVS clot shape influenced reperfusion and outcomes after MT for proximal middle-cerebral-artery (M1) occlusions. Methods: Between May 2015 and March 2018, consecutive patients who underwent MT at one comprehensive stroke center and who had a baseline MRI with a T2* sequence were included. Clinical, procedural and radiographic data, including clot shape on SVS [angulated/bifurcation (A-SVS) vs. straight (S-SVS)] and length were assessed. Primary outcome was successful reperfusion (TICI 2b-3). Secondary outcome were MT complication rates, MT reperfusion time, and clinical outcome at 90-days. Predictors of outcome were assessed with univariate and multivariate analyses. Results: A total of 62 patients were included. 56% (35/62) had an A-SVS. Clots were significantly longer in the A-SVS group (19 mm vs. 8 mm p = 0.0002). Groups were otherwise well-matched with regard to baseline characteristics. There was a significantly lower rate of successful reperfusion in the A-SVS cohort (83%) compared to the S-SVS cohort (96%) in multivariable analysis [OR 0.04 (95% CI, 0.002-0.58), p = 0.02]. There was no significant difference in long term clinical outcome between groups. Conclusion: Clot shape as determined on T2* imaging, in patients presenting with M1 occlusion appears to be a predictor of successful reperfusion after MT. Angulated and bifurcating clots are associated with poorer rates of successful reperfusion.

Biomechanical engineering analysis of commonly utilized mitral neochordae.

Objective: To evaluate the suture rupture forces of commonly clinically utilized neochord repair techniques to identify the most biomechanically resistant most biomechanically resistant technique. Methods: Several types of neochord techniques (standard interrupted neochordae, continuous running neochordae, and loop technique), numbers of neochordae, and suture calibers (polytetrafluoroethylene CV-3 to CV-6) were compared. To perform the tests, both ends of the neochordae were loaded in a tensile force analysis machine. During the test, the machine applied tension to the neochord until rupture was achieved. The tests were performed 3 times for each variation, and the rupture forces were averaged for statistical analysis. Results: Rupture force was significantly higher for running neochordae relative to interrupted neochordae (P < .01). However, a single rupture in the running technique resulted in failure of the complete neochord system. For both running and interrupted neochordae, a greater number of neochordae as well as a thicker suture caliber significantly increased the neochord rupture force (P < .01). The loop technique ruptured at significantly lower forces compared with the other 2 techniques (P < .01). A greater number of loops did not significantly increase the rupture force of loop neochordae. Observed rupture forces for all techniques were higher than those normally observed in physiologic conditions. Conclusions: Under experimental conditions, the running neochord technique has the best mechanical performance due to an increased rupture force. If using running neochordae, more than 1 independent set of multiple running neochordae are advised (ie, >2 independent sets of multiple running neochordae in each set).

Effect of Oxygen Extraction (Brush-Sign) on Baseline Core Infarct Depends on Collaterals (HIR).

Objectives: Baseline-core-infarct volume is a critical factor in patient selection and outcome in acute ischemic stroke (AIS) before mechanical thrombectomy (MT). We determined whether oxygen extraction efficiency and arterial collaterals, two different physiologic components of the cerebral ischemic cascade, interacted to modulate baseline-core-infarct volume in patients with AIS-LVO undergoing MT triage. Methods: Between January 2015 and March 2018, consecutive patients with an AIS and M1 occlusion considered for MT with a baseline MRI and perfusion-imaging were included. Variables such as baseline-core-infarct volume [mL], arterial collaterals (HIR: TMax > 10 s volume/TMax > 6 s), high oxygen extraction (HOE, presence of the brush-sign on T2*) were assessed. A linear-regression was used to test the interaction of HOE and HIR with baseline-core-infarct volume, after including potential confounding variables. Results: We included 103 patients. Median age was 70 (58-78), and 63% were female. Median baseline-core-infarct volume was 32 ml (IQR 8-74.5). Seventy six patients (74%) had HOE. In a multivariate analysis both favorable HIR collaterals (p = 0.02) and HOE (p = 0.038) were associated with lower baseline-core-infarct volume. However, HOE significantly interacted with HIR (p = 0.01) to predict baseline-core-infarct volume, favorable collaterals (low HIR) with HOE was associated with small baseline-core-infarct whereas patients with poor collaterals (high HIR) and HOE had large baseline-core-infarct. Conclusion: While HOE under effective collateral blood-flow has the lowest baseline-core-infarct volume of all patients, the protective effect of HOE reverses under poor collateral blood-flow and may be a maladaptive response to ischemic stroke as measured by core infarctions in AIS-LVO patients undergoing MT triage.