Comparative outcomes of lung volume reduction surgery and lung transplantation: a systematic review and meta-analysis.

Background: Lung volume reduction (LVR) and lung transplantation (LTx) have been used in different populations of chronic obstructive pulmonary disease (COPD) patients. To date, comparative study of LVR and LTx has not been performed. We sought to address this gap by pooling the existing evidence in the literature. Methods: An electronic search was performed to identify all prospective studies on LVR and LTx published since 2000. Baseline characteristics, perioperative variables, and clinical outcomes were extracted and pooled for meta-analysis. Results: The analysis included 65 prospective studies comprising 3,671 patients [LTx: 15 studies (n=1,445), LVR: 50 studies (n=2,226)]. Mean age was 60 [95% confidence interval (CI): 58-62] years and comparable between the two groups. Females were 51% (95% CI: 30-71%) in the LTx group vs. 28% (95% CI: 21-36%) in LVR group (P=0.05). Baseline 6-minute walk test (6MWT) and pulmonary function tests were comparable except for the forced expiratory volume in 1 second (FEV1), which was lower in the LTx group [21.8% (95% CI: 16.8-26.7%) vs. 27.3% (95% CI: 25.5-29.2%), P=0.04]. Postoperatively, both groups experienced improved FEV1, however post-LTx FEV1 was significantly higher than post-LVR FEV1 [54.9% (95% CI: 41.4-68.4%) vs. 32.5% (95% CI: 30.1-34.8%), P<0.01]. 6MWT was also improved after both procedures [LTx: 212.9 (95% CI: 119.0-306.9) to 454.4 m (95% CI: 334.7-574.2), P<0.01; LVR: 286 (95% CI: 270.2-301.9) to 409.1 m (95% CI: 392.1-426.0), P<0.01], however, with no significant difference between the groups. Pooled survival over time showed no significant difference between the groups. Conclusions: LTx results in better FEV1 but otherwise has comparable outcomes to LVR.

Utilization and outcomes of V-AV ECMO: A systematic review and meta-analysis.

BACKGROUND: Veno-arterial-venous extracorporeal membrane oxygenation (V-AV ECMO) is a less commonly used configuration of ECMO. We sought to understand the indications, utilization patterns, and outcomes of V-AV ECMO by quantitatively pooling the existing evidence from the literature. METHODS: Electronic search was performed to identify all relevant studies reporting V-AV ECMO usage. Five studies comprising 77 patients were selected and cohort-level data were extracted for further analysis. RESULTS: Mean patient age was 61 (95% CI: 55.2, 66.5) years and 30% (23/77) were female. The majority of cases [91% (70/77)] were transitioned to V-AV ECMO from another pre-existing ECMO configuration: V-A ECMO in 55% (42/77) vs. V-V ECMO in 36% (28/77), p = 0.04. Only 9% (7/77) of cases were directly placed on V-AV ECMO. The mean duration of hospital stay was 42.3 (95% CI: 10.5, 74.2) days, while ICU mortality was 46% (29, 64). Transition to durable left ventricular assist device was performed in 3% (2/64) of patients, while 3% (2/64) underwent heart transplantation. V-AV ECMO was successfully weaned to explantation in 33% (21/64) of patients. CONCLUSION: V-AV ECMO is a viable option for optimizing cardiopulmonary support in selected patients. Survival to weaning or bridging therapy appears comparable to more common ECMO configurations.

Bronchial artery revascularization in lung transplantation: a systematic review and meta-analysis.

Background: Bronchial artery revascularization (BAR) during lung transplantation has been hypothesized to improve early tracheal healing and delay the onset of bronchiolitis obliterans syndrome (BOS). We aimed to assess the outcomes of BAR after lung transplantation. Methods: Electronic search in Ovid Medline, Cumulative Index of Nursing and Allied Health Literature (CINAHL), Scopus, and Cochrane Controlled Trials Register (CCTR) databases was performed to identify all relevant studies published about lung transplantation with BAR. Studies discussing lung transplantation utilizing BAR were included while those without outcome data such as BOS and survival were excluded. Cohort-level data were extracted and pooled for analysis. A binary outcome meta-analysis of proportions with logit transformation was conducted. Newcastle-Ottawa scale was used for risk of bias assessment. Results: Seven studies were selected for the analysis comprising 143 patients. Mean patient age was 47 (95% CI: 40-55) years. Sixty-one percent (48-72%) were male. Seventy-three percent (65-79%) of patients underwent double lung transplant while 27% (21-25%) underwent single lung transplant. In patients with postoperative angiography, successful BAR was demonstrated in 93% (82-97%) of all assessed conduits. The 30-day/in-hospital mortality was 6% (3-11%). Seventy-nine percent (63-89%) of patients were free from rejection at three months. Eighty-three percent (29-98%) of patients were free from signs of airway ischemia at three and six months. Pooled survival at one year and five years was 87% (78-92%) and 71% (46-87%), respectively, with a mean follow-up time of 21 (3-38) months. Pooled freedom from bronchiolitis obliterans was 86% (77-91%) at two years. Conclusions: While this systematic review and meta-analysis is limited by the available surgeons, institutions, and papers discussing a highly specialized technique, it does show that BAR is a viable technique to minimize BOS and early anastomotic intervention following lung transplantation.

Extracorporeal life support and cardiopulmonary bypass for central airway surgery: A systematic review.

BACKGROUND: Major airway surgery can pose a complex problem to perioperative central airway management. Adjuncts to advanced ventilation strategies have included cardiopulmonary bypass, veno-arterial, or veno-venous extracorporeal life support. We performed a systematic review to assess the existing evidence utilizing these strategies. METHODS: An electronic search was conducted to identify studies written in English reporting the use of extracorporeal life support (ECLS) during central airway surgery. Thirty-six articles consisting of 78 patients were selected and patient-level data were analyzed. RESULTS: Median patient age was 47 [IQR: 34-53] and 59.0% (46/78) were male. Indications for surgery included central airway or mediastinal cancer in 57.7% (45/78), lesion or injury in 15.4% (12/78), and stenosis in 12.8% (10/78). Support was initiated pre-operatively in 9.9% (7/71) and at the time of induction in 55.3% (42/76). It was most commonly used at the time of tracheal resection/repair [93.2% (68/73)], intubation of the tracheal stump [94.4% (68/72)], and re-anastomosis [94.2% (65/69)]; 13.7% (10/73) patients were supported post-operatively. The most commonly performed surgery was tracheal repair or resection in 70.3% (52/74). Median hospital stay was 12 [8, 25] days and in-hospital mortality was 7.9% (6/76). There was no significant difference in survival between the three groups (p = .54). CONCLUSIONS: Extracorporeal membrane oxygenation offers versatility in timing, surgical approach, and ECLS runtime that makes it a viable addition to the surgical armamentarium for treating complex central airway pathologies.

Utilization and outcomes of extracorporeal CO2 removal (ECCO2 R): Systematic review and meta-analysis of arterio-venous and veno-venous ECCO2 R approaches.

INTRODUCTION: Extracorporeal carbon dioxide removal (ECCO2 R) provides respiratory support to patients suffering from hypercapnic respiratory failure by utilizing an extracorporeal shunt and gas exchange membrane to remove CO2 from either the venous (VV-ECCO2 R) or arterial (AV-ECCO2 R) system before return into the venous site. AV-ECCO2 R relies on the patient's native cardiac function to generate pressures needed to deliver blood through the extracorporeal circuit. VV-ECCO2 R utilizes a mechanical pump and can be used to treat patients with inadequate native cardiac function. We sought to evaluate the existing evidence comparing the subgroups of patients supported on VV and AV-ECCO2 R devices. METHODS: A literature search was performed to identify all relevant studies published between 2000 and 2019. Demographic information, medical indications, perioperative variables, and clinical outcomes were extracted for systematic review and meta-analysis. RESULTS: Twenty-five studies including 826 patients were reviewed. 60% of patients (497/826) were supported on VV-ECCO2 R. The most frequent indications were acute respiratory distress syndrome (ARDS) [69%, (95%CI: 53%-82%)] and chronic obstructive pulmonary disease (COPD) [49%, (95%CI: 37%-60%)]. ICU length of stay was significantly shorter in patients supported on VV-ECCO2 R compared to AV-ECCO2 R [15 (95%CI: 7-23) vs. 42 (95%CI: 17-67) days, p = 0.05]. In-hospital mortality was not significantly different [27% (95%CI: 18%-38%) vs. 36% (95%CI: 24%-51%), p = 0.26]. CONCLUSION: Both VV and AV-ECCO2 R provided clinically meaningful CO2 removal with comparable mortality.

Computational sentiment analysis of an online left ventricular assist device support forum: positivity predominates.

BACKGROUND: The impact of left ventricular assist device (LVAD) complications on the individual patient, overall sentiment, and its effect on referral patterns, is not fully understood. We sought to better understand patient attitudes towards LVAD therapy using a computational sentiment analysis approach. METHODS: Posts, comments, and titles were parsed from MyLVAD.com's HTML as a text file using custom Python scripts (version 3.6). Individual word frequency was computed with word classification as 'positive', 'negative', or 'neutral'. Data transformation and cleaning, sentiment determination, and analysis was performed with a binary dictionary package using R software (version 3.6). RESULTS: Sixty-six thousand eight hundred and twenty-one unique words were noted, including 4,623 (6.9%) with positive sentiment and 3,248 (4.8%) with negative sentiment. Net sentiment ratio [(number of positive words - number of negative words)/(number of total words)] was 2.1%. Positive sentiment dominated the 20 most commonly used words. Odds ratio of non-neutral words [(number of positive words/number of negative words)] was 1.42, indicating a less obvious disparity in sentiment when expanding analysis beyond the top 20 words. Word cloud analysis of positive and negative sentiments was performed, indicating common use of "infection" (208 mentions) compared to other complications such as "stroke" (29 mentions), "bleeding" (30 mentions), and "thrombosis" or "clot" (32 mentions). CONCLUSIONS: Positive sentiment dominates the most frequently used words, yet this disparity decreases when considering the totality of words. "Infection" is mentioned a disproportionate number of times compared to other LVAD complications. Further research is required to address analysis limitations, including selection bias.

Outcomes of surgical treatment for carcinoid heart disease: A systematic review and meta-analysis.

BACKGROUND: Carcinoid heart disease (CaHD) develops from vasoactive substances released by neuroendocrine tumors, which can cause significant patient morbidity and mortality without surgical intervention. We performed a systematic review and meta-analysis to elucidate granular perioperative details and long-term outcomes in these patients. METHODS: Electronic search of Ovid, Scopus, Cumulative Index of Nursing and Allied Health Literature, and Cochrane Controlled Trials Register was performed to examine surgical treatment of carcinoid disease. Nine articles comprising 416 patients were selected. Study-level data were extracted and pooled for meta-analysis. RESULTS: Mean patient age was 63 years (95% confidence interval, 57-70) with 53% (95% confidence interval, 46-61) of patients being male. In addition, 75% (95% confidence interval, 54-96) of neuroendocrine tumors originated from the small bowel or colon and 98% (95% confidence interval, 93-100) had liver metastases. Right heart failure was present in 48% (95% confidence interval, 14-81). Moderate or severe regurgitation was present in 97% (95% confidence interval, 95-99) of tricuspid and 72% (95% confidence interval, 58-83) of pulmonary valves. In addition, 99% (95% confidence interval, 98-100) of tricuspid and 59% (95% confidence interval, 38-79) of pulmonary valves were replaced. Bioprosthetic valves were used in 80% (95% confidence interval, 68-93) of tricuspid positions. Mean hospital duration of stay was 16 days (95% confidence interval, 7-25). Thirty-day mortality was 9% (95% confidence interval, 6-12). Mean follow-up was 25 months (95% confidence interval, 11-39). Median survival was 3 years (95% confidence interval, 2.5-3.5). CONCLUSION: For patients >18 years of age, surgical treatment of carcinoid heart disease can be performed with a reasonable safety profile. However, overall survival appears to have ongoing effects of the primary disease.

Evaluation of Endovascular Intervention for Tracheo-Innominate Artery Fistula: A Systematic Review.

BACKGROUND: While the standard of care for suspected tracheo-innominate artery fistula (TIF) necessitates sternotomy, perioperative mortality remains high. Endovascular interventions have been attempted, but reports have been anecdotal. The aim of this systematic review was to evaluate the outcomes of endovascular management of TIF by pooling the existing evidence. METHODS: An electronic database search of Ovid MEDLINE, Scopus, Cumulative Index to Nursing and Allied Health Literature, and Cochrane Controlled Trials Register was performed to identify all studies examining endovascular treatment of TIF. Patients greater than 14 years of age who underwent endovascular intervention for TIF were included. 25 studies consisting of 27 patients met the inclusion criteria. RESULTS: 48.1% (13/27) of patients were male and median age was 39.0 [IQR 16.0, 47.5] years. Tracheostomy was present in 96.3% (26/27) of cases. Median duration from tracheostomy to TIF presentation was 2.2 months [0.5, 42.5]. On presentation, 84.6% (22/26) had tracheal hemorrhage, and 22.8% (6/27) were hemodynamically unstable. 96.3% (26/27) underwent covered stent graft placement while 1 patient (3.8%) had coil embolization. 18.5% (5/27) of patients required repeat endovascular intervention for recurrent bleeding, while 11.1% (3/27) required rescue sternotomy. Median hospital length of stay was 30 days [16.0, 46.5], and overall mortality was 29.6% (8/27) with a median follow-up time of 5 months [1.2, 11.5]. CONCLUSION: While uncommon, endovascular treatment of TIF may be a feasible alternative to sternotomy. The approach may be useful in those who are unable to undergo surgery or are likely to have adhesions from prior chest operations.

Utilization of extracorporeal life support for diffuse alveolar damage and diffuse alveolar hemorrhage: A systematic review.

Modern extracorporeal life-support (ECLS) technology has been successfully utilized to treat patients with diffuse alveolar damage (DAD) and diffuse alveolar hemorrhage (DAH); however, reports in the literature remain scarce. We sought to pool existing evidence to better characterize ECLS use in these patients. An electronic search was conducted to identify all studies in the English literature reporting the use of ECLS for DAD/DAH. Thirty-two articles consisting of 38 patients were selected, and patient-level data were extracted and pooled for analysis. Median patient age was 36 [IQR: 27, 48] years, and the majority (63.2%) were female. Most common etiological factors included granulomatosis with polyangiitis (8/38, 21.1%), systemic lupus erythematosus (8/38, 21.1%), Goodpasture's syndrome (4/38, 10.5%), and microscopic polyangiitis (4/38, 10.5%). Immunologic markers included anti-neutrophil cytoplasmic antibody (ANCA) in 15/38 (39.5%), anti-nuclear antibody (ANA) in 6/38 (15.8%), and anti-glomerular basement membrane (anti-GBM) antibodies in 4/38 (10.5%). DAH was present in 32/38 (84.2%) of cases and DAD without evidence of DAH was present in 6/38 (15.8%) of cases. ECLS strategies included extracorporeal membrane oxygenation of veno-venous type (VV-ECMO) in 28/38 (73.7%), veno-arterial type (VA-ECMO) in 5/38 (13.2%), and one case of right ventricular assist device with oxygenator (RVAD-ECMO). Heparin was utilized in 18/38 (47.4%) of cases with no difference in use between DAH versus no DAH (P = .46) or VA- versus VV-ECLS (P = 1). Median duration of ECLS was 10 [5, 14] days. Pre- versus post-ECLS comparison of blood gases showed improvement in median PaO2 (49 [45, 59] mm Hg vs. 80 [70, 99] mm Hg, P < .001), PaO2:FiO2 ratio (48.2 [41.4, 54.8] vs. 182.0 [149.4, 212.2], P < .01), and pulse oximetry values (76% [72, 80] vs. 96% [94, 97], P = .086). Overall, 94.7% (36/38) of patients survived to decannulation while 30-day mortality was 10.5% (4/38) with no differences between VA- and VV-ECMO (P = 1 and P = .94, respectively). DAD/DAH occurs in a younger, predominantly female population, and tends to be associated with systemic autoimmune processes. ECLS, independent of its type, appears to result in favorable short-term survival.

Driveline damage and repair in continuous-flow left ventricular assist devices: A systematic review.

With mounting time on continuous-flow left ventricular assist device (CF-LVAD) support, patients occasionally sustain damage to the device driveline. Outcomes associated with external and internal driveline damage and repair are currently not well documented. We sought to evaluate the outcomes of driveline damage and its repair. Electronic search was performed to identify all relevant studies published over the past 20 years. Fifteen studies were selected for analysis comprising of 55 patients with CF-LVAD dysfunction due to driveline damage. Demographic and perioperative variables along with outcomes including survival rates were extracted and pooled for the systematic review. Most patients (53/55) were supported on HeartMate II LVAD (Abbott Laboratories, Abbott Park, IL). Internal damage was more commonly reported than external damage [69.1% (38/55) vs. 30.9% (17/55), P = .01]. Median time to driveline damage was 1.9 years [IQR 1.0, 2.5]. Most patients presented with a CF-LVAD alarm [94.5% (52/55)] and patients with internal driveline damage had a significantly higher rate of alarm activation compared to that observed for those with external damage [38/38 (100%) vs. 14/17 (82.4%), P = .04]. Patients with internal driveline dysfunction were more likely to experience component wear compared to those with external driveline dysfunction [10/38 (26.3%) vs. 0/17 (0%), P = .05]; 14.5% of patients (8/55) underwent external repair of the driveline, 5.5% (3/55) were treated with rescue tape, and 5.5% (3/55) were placed on an ungrounded cable, indicating a short-to-shield event had occurred. A total of 49.1% of patients (27/55) underwent CF-LVAD exchange, 5.5% (3/55) were weaned off the CF-LVAD to explant, and 5.5% (3/55) underwent emergent heart transplantation. The median length of hospital stay was 12 days [IQR 7, 12] and 30-day mortality rate was 14.5% (8/55). Driveline damage was more commonly reported at an internal location and despite being a well-recognized complication, mortality still appears high.

Outcomes of Mechanical Circulatory Support for Giant Cell Myocarditis: A Systematic Review.

Treatment of giant cell myocarditis (GCM) can require bridging to orthotopic heart transplantation (OHT) or recovery with mechanical circulatory support (MCS). Since the roles of MCS and immunotherapy are not well-defined in GCM, we sought to analyze outcomes of patients with GCM who required MCS. A systematic search was performed in June 2019 to identify all studies of biopsy-proven GCM requiring MCS after 2009. We identified 27 studies with 43 patients. Patient-level data were extracted for analysis. Median patient age was 45 (interquartile range (IQR): 32-57) years. 42.1% (16/38) were female. 34.9% (15/43) presented in acute heart failure. 20.9% (9/43) presented in cardiogenic shock. Biventricular (BiVAD) MCS was required in 76.7% (33/43) of cases. Of the 62.8% (27/43) of patients who received immunotherapy, 81.5% (22/27) used steroids combined with at least one other immunosuppressant. Cyclosporine was the most common non-steroidal agent, used in 40.7% (11/27) of regimens. Immunosuppression was initiated before MCS in 59.3% (16/27) of cases, after MCS in 29.6% (8/27), and not specified in 11.1% (3/27). Immunosuppression started prior to MCS was associated with significantly better survival than MCS alone (p = 0.006); 60.5% (26/43) of patients received bridge-to-transplant MCS; 39.5% (17/43) received bridge-to-recovery MCS; 58.5% (24/41) underwent OHT a median of 104 (58-255) days from diagnosis. GCM recurrence after OHT was reported in 8.3% (2/24) of transplanted cases. BiVAD predominates in mechanically supported patients with GCM. Survival and bridge to recovery appear better in patients on immunosuppression, especially if initiated before MCS.