Taking the pulse of brain death: A meta-analysis of the natural history of brain death with somatic support.

BACKGROUND AND PURPOSE: The conceptualization of brain death (BD) was pivotal in the shaping of judicial and medical practices. Nonetheless, media reports of alleged recovery from BD reinforced the criticism that this construct is a self-fulfilling prophecy (by treatment withdrawal or organ donation). We meta-analyzed the natural history of BD when somatic support (SS) is maintained. METHODS: Publications on BD were eligible if the following were reported: aggregated data on its natural history with SS; and patient-level data that allowed censoring at the time of treatment withdrawal or organ donation. Endpoints were as follows: rate of somatic expiration after BD with SS; BD misdiagnosis, including "functionally brain-dead" patients (FBD; i.e. after the pronouncement of brain-death, ≥1 findings were incongruent with guidelines for its diagnosis, albeit the lethal prognosis was not altered); and length and predictors of somatic survival. RESULTS: Forty-seven articles were selected (1610 patients, years: 1969-2021). In BD patients with SS, median age was 32.9 years (range = newborn-85 years). Somatic expiration followed BD in 99.9% (95% confidence interval = 89.8-100). Mean somatic survival was 8.0 days (range = 1.6 h-19.5 years). Only age at BD diagnosis was an independent predictor of somatic survival length (coefficient = -11.8, SE = 4, p < 0.01). Nine BD misdiagnoses were detected; eight were FBD, and one newborn fully recovered. No patient ever recovered from chronic BD (≥1 week somatic survival). CONCLUSIONS: BD diagnosis is reliable. Diagnostic criteria should be fine-tuned to avoid the small incidence of misdiagnosis, which nonetheless does not alter the prognosis of FBD patients. Age at BD diagnosis is inversely proportional to somatic survival.

Diabetes Mellitus is an Independent Predictor of Spinal Cord Injury After Descending Thoracic and Thoracoabdominal Aneurysm Repair: Maximum Likelihood Conditional Regression in a Propensity-Score Matched Cohort.

OBJECTIVE: To discern the impact of diabetes mellitus (DM) on spinal cord injury (SCI) after open descending thoracic and thoracoabdominal aneurysm repair (DTAAAR). BACKGROUND: Compared with euglycemia, hyperglycemia, and ketosis make neurons respectively more vulnerable and more resilient to ischemia. METHODS: During the study period (1997-2021), patient who underwent DTAAAR were dichotomized according to the presence/absence of DM. The latter was investigated as predictor of our primary (SCI) and secondary [operative mortality (OM), myocardial infarction, stroke, need for tracheostomy, de novo dialysis, and survival] endpoints. Two-level risk-adjustment employed maximum likelihood conditional regression after 1:2 propensity-score matching. RESULTS: DTAAAR was performed in 934 patients. Ninety-two diabetics were matched to 184 nondiabetics. All preoperative variables had a standardized mean difference <0.1 between the matched groups. Patients with DM had higher SCI (6.5% vs. 1.6%, P 0.03) and OM (14.1% vs. 6.0%, P =0.01), while the other secondary endpoints were similar between groups in the matched sample. DM was an independent predictor for SCI in the matched sample (odds ratio: 5.05, 95% confidence interval: 1.17-21.71). Matched patients with DM presented decreased survival at 1 (70.2% vs. 86.2%), 5 (50.4% vas 67.5%), 10 years (31.7% vs. 36.7%) ( P =0.03). The results are summarized in the graphical abstract. CONCLUSION: DM is associated to increased OM and decreased survival, and it is an independent predictor of SCI after open DTAAAR. Strict perioperative glycemic control should be implemented, and exogenous ketones should be investigated as neuroprotective agents to reduce such adverse events.

Systematic Review - Neuroprotection of ketosis in acute injury of the mammalian central nervous system: A meta-analysis.

To evaluate the neuroprotection exerted by ketosis against acute damage of the mammalian central nervous system (CNS). Search engines were interrogated to identify experimental studies comparing the mitigating effect of ketosis (intervention) versus non-ketosis (control) on acute CNS damage. Primary endpoint was a reduction in mortality. Secondary endpoints were a reduction in neuronal damage and dysfunction, and an 'aggregated advantage' (composite of all primary and secondary endpoints). Hedges' g was the effect measure. Subgroup analyses evaluated the modulatory effect of age, insult type, and injury site. Meta-regression evaluated timing, type, and magnitude of intervention as predictors of neuroprotection. The selected publications were 49 experimental murine studies (period 1979-2020). The intervention reduced mortality (g 2.45, SE 0.48, p < .01), neuronal damage (g 1.96, SE 0.23, p < .01) and dysfunction (g 0.99, SE 0.10, p < .01). Reduction of mortality was particularly pronounced in the adult subgroup (g 2.71, SE 0.57, p < .01). The aggregated advantage of ketosis was stronger in the pediatric (g 3.98, SE 0.71, p < .01), brain (g 1.96, SE 0.18, p < .01), and ischemic insult (g 2.20, SE 0.23, p < .01) subgroups. Only the magnitude of intervention was a predictor of neuroprotection (g 0.07, SE 0.03, p 0.01 per every mmol/L increase in ketone levels). Ketosis exerts a potent neuroprotection against acute damage to the mammalian CNS in terms of reduction of mortality, of neuronal damage and dysfunction. Hematic levels of ketones are directly proportional to the effect size of neuroprotection.

Splanchnic occlusive disease predicts for spinal cord injury after open descending thoracic and thoracoabdominal aneurysm repair.

OBJECTIVE: In the present study, we sought to discern the effects of splanchnic occlusive disease (SOD; renal, superior mesenteric, and/or celiac axis arteries) on spinal cord injury (SCI; paraparesis or paraplegia) and major adverse events (MAE) after descending thoracic aneurysm (DTA) and thoracoabdominal aortic aneurysm (TAAA) open repair. METHODS: Patients who had undergone DTA/TAAA repair at our institution were dichotomized according to the presence of SOD, which was investigated as a predictive factor of our primary (SCI) and secondary (operative mortality, myocardial infarction, stroke, tracheostomy, de novo dialysis, MAE, survival) endpoints. Risk adjustment used both propensity score matching and multivariable logistic regression. RESULTS: From July 1997 to October 2019, 888 patients had undergone DTA/TAAA repair, of whom 19 were excluded from our analysis for missing data. SOD was absent in 712 patients and present in 157 patients. The patients with SOD had presented with a greater incidence of preoperative renal impairment (61 [38.9%] vs 175 [24.6%]; P < .01) and peripheral arterial disease (60 [38.2%] vs 162 [22.8%]; P < .01] and decreased left ventricular ejection fraction (45%; interquartile range, 10%; vs 50%; interquartile range, 4%; P < .01). The etiology of aortic disease was more frequently dissection in the SOD group (56.1% vs 43.7%) and more frequently nondissecting aneurysm in the non-SOD group (56.3% vs 43.9%; P < .01). Patients without SOD had presented with aneurysms more cranially located (DTA, 34.0% vs 7.6%; extent I TAAA, 44.0% vs 7.6%). In contrast, patients with SOD had presented with aneurysms more caudally located (extent II TAAA, 36.9% vs 8.6%; extent III TAAA, 30.6% vs 11.0%; extent IV TAAA, 17.2% vs 2.5%; P < .01). Propensity score matching led to 144 pairs, with SOD significantly associated with SCI (10 [6.9%] vs 2 [1.4%]; P = .03) and MAE (47 [32.6%] vs 26 [15%]; P < .01). Ten-year survival was reduced in those with SOD (31.5% vs 45.2%; P < .01). Conditional multivariable regression confirmed SOD to be a predictor of SCI in the matched sample (odds ratio, 6.60; P = .02). CONCLUSIONS: Our results have shown that SOD is a significant predictor of SCI in patients undergoing open DTA/TAAA repair. The investigation of measures to prolong neuronal ischemia tolerance (eg, hypothermia) is warranted for such patients.

Meta-Analysis of the Effect of Vascular Complications on Mortality in Patients Undergoing Femoral Venoarterial Extracorporeal Membrane Oxygenation.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) has become an accepted treatment modality in the management of select patients with cardiopulmonary failure. As a result, its use has increased significantly over the past decade. However, the effect of complications on mortality is not clearly established. We performed a comprehensive, up-to-date meta-analysis of peer-reviewed literature focusing on the effect of vascular complications (VCs) on the survival of patients receiving venoarterial ECMO (VA-ECMO) with femoral cannulation. METHODS: A systematic search of 4 different databases (PubMed, Embase, Scopus, and Web of Science) was conducted from their inception to mid-September of 2019. To keep the pooled analysis current, only studies published within the past 5 years were included. Mortality was analyzed based on presence or absence of VCs. Studies with less then 10 patients, with incomplete mortality data, and not accessible in the English language were excluded. RESULTS: Ten studies were included in the analysis encompassing 1,643 patients over a 5-year period. There were 369 patients with a cumulative VC rate of 22.5% (range 9.4 to 43.9%). The pooled mortality rate for patients with and without VCs was 69.6% and 56.8%, respectively. Meta-analysis demonstrated a significant correlation between VCs and mortality with a relative risk (RR) of 1.36 (95% confidence interval (CI), 1.15-1.60; P = 0.0004). Covariate-adjusted meta-regression analysis revealed an inverse relationship between age and mortality for VCs, with an RR of 1.33 (95% CI, 1.15-1.54; P = 0.0184), and direct relationship between female gender and mortality from VCs, RR 1.39 (95% CI, 1.21-1.59; P = 0.0165). CONCLUSIONS: The most recently available data published in the literature demonstrate a significant correlation of VCs with mortality. Therefore, aggressive attempts should be made to minimize VCs in patients with femoral VA-ECMO cannulation.

Thoracotomy versus sternotomy? The effect of surgical approach on outcomes after left ventricular assist device implantation: A review of the literature and meta-analysis.

BACKGROUND AND AIM: Thoracotomy approaches to left ventricular assist device (LVAD) implantation may reduce surgical morbidity and, through preservation of the pericardial restraint over the right heart, may reduce the incidence of right ventricular failure (RVF). METHODS: A meta-analysis of all original studies describing the effect of the surgical approach on postoperative outcomes after LVAD implantation was performed. Postoperative outcomes analyzed. RESULTS: Thirteen studies were included with 692 patients undergoing a sternotomy and 373 a thoracotomy approach. Patients undergoing a thoracotomy approach had a higher comorbid status (INTERMACS 1-2: 56% vs. 44%; p = .0004), but were less likely to undergo a concomitant procedure (4% vs. 15%; p = .0002) than patients undergoing a sternotomy approach. Patients undergoing a thoracotomy approach demonstrated a reduced incidence of RVF (OR, .47; CI, .23-.97; p = .04), reexploration for bleeding (OR, .55; CI, .32-.94; p = .03), perioperative blood transfusion (SMD, -.30; CI, -.49 to -.11; p = .002), LOS (-5.57; -10.56 to -.59; p = .03), and mortality (OR, .57; CI, .33-.98; p = .04), but no difference in RVAD requirement or stroke were noted. Metaregression demonstrated that the performance of a concomitant procedure did not modify the effect of the surgical approach on the primary endpoints of RVF or RVAD requirement. CONCLUSIONS: In the current meta-analysis including over 1000 patients undergoing LVAD implantation, a thoracotomy approach was associated with a reduced incidence of RVF (but not RVAD requirement), bleeding, LOS, and mortality. No difference in stroke rates was noted. These findings not only offer additional support as to the feasibility of a thoracotomy approach for LVAD implantation but also suggest a potential superiority over a sternotomy approach.

High-Frequency Percussive Ventilation Rescue Therapy in Morbidly Obese Patients Failing Conventional Mechanical Ventilation.

BACKGROUND: Morbidly obese patients with respiratory failure who do not improve on conventional mechanical ventilation (CMV) often undergo rescue therapy with extracorporeal membrane oxygenation (ECMO). We describe our experience with high-frequency percussive ventilation (HFPV) as a rescue modality. METHODS: In a retrospective analysis from 2009 to 2016, 12 morbidly obese patients underwent HFPV after failing to wean from CMV. Data were collected regarding demographics, cause of respiratory failure, ventilation settings, and hospital course outcomes. Our end point data were pre- and post-HFPV partial pressure of arterial oxygen and PaO2 to fraction of inspired oxygen (PF) ratios measured at initiation, 2, and 24 hours. RESULTS: Twelve morbidly obese patients required HFPV for respiratory failure. Causes of respiratory failure overlapped and included cardiogenic pulmonary edema (n = 8), pneumonia (n = 5), septic shock (n = 5), and asthma (n = 1). After HFPV initiation, mean fraction of inspired oxygen FiO2 was tapered from 98% to 82% and 66% at 2 and 24 hours, respectively. Mean PaO2 increased from 60.9 mm Hg before HFPV to 175.1 mm Hg (P < .05) at initiation of HFPV, then sustained at 129.5 mm Hg (P < .05) and 88.1 mm Hg (P < .005) at 2 and 24 hours, respectively. Mean PF ratio improved from 66.1 before HFPV to 180.3 (P < .05), 181.0 (P < .05) and 148.9 (P < .0005) at initiation, 2, and 24 hours, respectively. The improvement in mean PaO2 and PF ratios was durable at 24 hours whether or not the patient was returned to CMV (n = 10) or remained on HFPV (n = 2). Survival to discharge was 66.7%. CONCLUSION: In our cohort of morbidly obese patients, HFPV was successfully utilized as a rescue therapy precluding the need for ECMO. Despite our small sample size, HFPV should be considered as a rescue therapy in morbidly obese patients failing CMV prior to the initiation of ECMO. Our retrospective analysis supports consideration for HFPV as another form of rescue therapy for obese patients with refractory hypoxemia and respiratory failure who are not improving with CMV.

The Effect of Acute Limb Ischemia on Mortality in Patients Undergoing Femoral Venoarterial Extracorporeal Membrane Oxygenation.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) is a life-saving modality increasingly used in the management cardiopulmonary failure. However, ECMO itself is not without major complications. Mortality remains high, and morbidity such as stroke, renal failure, and acute limb threatening ischemia (ALI) are common among surviving patients. We analyzed the effect of one of these complications, ALI, on the survival of patients receiving venoarterial ECMO (VA ECMO) with femoral cannulation. METHODS: Patients with cardiopulmonary failure supported by VA ECMO inserted through femoral cannulation at two institutions from December 2010 to December 2017 were enrolled in this study. Data were collected retrospectively. Our primary outcome was ALI and its effect on hospital mortality. Secondary outcomes included six-month mortality, length of hospital stay, and other complications (stroke and renal failure); multivariate logistic regression analysis was used to identify predictors of ALI and hospital mortality. RESULTS: There were 71 patients included in this study. The overall VA ECMO hospital mortality was 53.5%. ALI was seen in 14 (19.7%) patients. Of these, four (5.6%) patients had fasciotomy, four patients (5.6%) had thrombectomy, and one underwent arterial repair (1.4%). Five additional patients (7.0%) with ALI expired and had no vascular intervention. None of the demographic and clinical characteristics significantly correlated with ALI except for stroke and renal failure requiring new-onset hemodialysis (HD). The rate of hospital and 6-month mortality in patients with and without vascular complications were 78.6%, 92.3% and 47.4%, 57.4%, respectively (P = 0.042 and P = 0.023). Multivariate analysis correlated hospital and six-month mortality with ALI, stroke, and new-onset HD. CONCLUSIONS: ALI correlates with higher mortality in VA ECMO patients with femoral cannulation. Although some of the contributing factors to mortality in these patients are related to the consequences of cardiopulmonary failure, strong efforts should be made to avoid ALI after femoral VA ECMO cannulation.

Convergent ablation for persistent atrial fibrillation: Single center experience.

BACKGROUND: Endocardial catheter ablation has been shown to be effective in patients with paroxysmal atrial fibrillation (AF), and significantly less effective in patients with persistent AF (PAF). Lately, there is a trend toward a hybrid approach in the treatment of PAF that may be a more durable treatment for patients with PAF. In this manuscript we report our experience with the convergent ablation procedure in a PAF cohort. METHODS: This is a single center retrospective analysis of 31 patients with PAF who underwent the convergent procedure. All patients underwent surgical epicardial ablation of the posterior left atrial through a subxiphoid approach, followed by radiofrequency endocardial ablations on the same day. Patients were followed at 6 months intervals with static electrocardiograms or implanted devices. RESULTS: Sinus rhythm was achieved intraoperatively in all patients. Recurrence was defined according to Hearlt Rhythm Society definitions. At a median follow up of 17.7 months (IQR 11-24), the recurrence of atrial tachyarrhythmia (AF and atrial flutter) by Kaplan-Meier event free survival analysis occurred in 9 (29%) patients at 1-year follow up and 15 (48%) patients at 2-year follow up with or without the use of antiarrhythmic drugs. Recurrence of AF alone occurred in 4 (13%) patients at 1-year follow up and 9 (29%) patients at 2-year follow up patients. Complication rate in perioperative period was 12.9%. CONCLUSION: Our experience showed the hybrid procedure is a relatively safe and effective option for patients with PAF. Further studies are needed to better determine its long-term outcomes.

AngioVac for extraction of venous thromboses and endocardial vegetations: A meta-analysis.

BACKGROUND: AngioVac is a new device for filtering intravascular thrombi and emboli. Publications on the device are limited and underpowered to objectively estimate its safety and efficacy. We aimed to overcome this by performing a meta-analysis on the results of AngioVac for treating venous thromboses and endocardial vegetations. METHODS: A systematic literature review was performed to identify all articles reporting cardiac vegetation and/or thrombosis extraction using AngioVac. Endpoints were successful removal, operative mortality, conversion to open surgery, hospital stay, recurrent thromboembolism, and follow-up mortality. Random effect model was used, and pooled event rates (PERs) and incidence rate (IR) were calculated. RESULTS: A total of 42 studies with 182 patients (81 vegetation and 101 thrombosis) were included. Overall mean follow-up times were 3.1 and 0.7 years in vegetation and thrombosis patients, respectively. The PERs for successful removal were 74.5 (confidence interval [CI]: 48.2-90.2), 80.5 (CI: 70.0-88.0), and 32.4 (CI: 17.0-52.8) in vegetation, right atrial/caval venous thrombi, and pulmonary emboli (PE) patients, respectively. The PERs for operative mortalities were 14.6 (CI: 7.7-25.8), 14.8 (CI: 8.5-24.5), and 32.3 (CI: 15.1-56.3), respectively. The PERs for conversion to open surgery were 25.0 (CI: 9.3-51.9) and 12.3 (CI: 5.4-25.6) in vegetation and thrombosis patients, respectively. The IR of recurrent thromboembolism was 0.18 per person per year (PPY) (CI: 0.00-14.69) in vegetation and 0.19 PPY (CI: 0.08-0.48) in thrombosis patients. IR of follow-up mortality was 0.37 PPY (CI: 0.11-1.21) in thrombosis patients. CONCLUSIONS: AngioVac is a viable option for extracting right-sided vegetations and right atrial/caval venous thrombi. Rates of successful extraction and mortality are significantly worse for PE.

Pulmonary artery aneurysms: Preoperative, intraoperative, and postoperative findings.

BACKGROUND: Pulmonary artery aneurysms (PAAs) are a rare but potentially lethal cardiovascular pathology. PAAs tend to develop in young patients with no gender discrepancy; they are most often associated with congenital heart disorders but also with systemic infections, vasculitis, pulmonary arterial hypertension, chronic pulmonary embolism, and malignancies. Dissection and rupture carry significant morbidity and mortality, thus patients require careful management, especially those with associated pulmonary hypertension. Given the rarity of this condition, physicians have yet to establish standard treatment guidelines. Most studies published to date are case reports with one or two patients; here, we describe our experience with six cases of large PAAs treated surgically at our institution. METHODS: We identified and retrospectively analyzed clinical data for patients who underwent surgery for PAAs between 2009 and 2017. RESULTS: The average age at surgery was 59.73 years, five patients were females, and 83.3% had baseline hypertension. Systolic murmurs were the most common clinical finding. The average aneurysmal size was 65.0 mm. We repaired the PAA with a woven Dacron graft (22-26 mm) in four patients. We performed concomitant pulmonary valve procedures on five patients: four replacements and one repair. Mean pump and cross-clamp times were 108.5 and 65 minutes. Operative and 30-day mortality was 0%. Average length of stay was 10.5 days. CONCLUSIONS: Postoperative mortality was 0%; all patients showed improvement of symptoms after surgery. These findings confirm that PAA repair has an acceptable risk profile in select patients.

Sinus of Valsalva aneurysm repairs: Operative technique and lessons learned.

OBJECTIVE: Sinus of Valsalva (SOV) aneurysms are rare and data on operative management are limited. They can cause right ventricular outflow tract or pulmonary artery compression, and rupture may be fatal. In this study, we describe our experience with the repair of 13 SOV aneurysms. METHODS: All patients who underwent SOV aneurysm repair from May 2001 to December 2017 at our single tertiary referral center were reviewed retrospectively. RESULTS: Thirteen patients (92% male) with a mean age of 60 years underwent repair of an SOV aneurysm; mean aneurysm diameter was 5.9 ± 0.8 cm and four patients (30.7%) presented with rupture into another cardiac chamber. Operative interventions included six Bentall procedures, five patch repairs (one with aortic valve replacement [AVR]), and two primary aneurysm closures both with concomitant AVR. There were no strokes, myocardial infarctions, re-explorations, or deaths in the postoperative period. After an average of 2.25 years, computed tomographic imaging in five patients demonstrated no aneurysm recurrence. CONCLUSIONS: Surgery is a safe option for both ruptured and nonruptured SOV aneurysms. A variety of repair strategies may be used. Larger studies are needed.

A Simple Scoring System to Predict Survival after Venoarterial Extracorporeal Membrane Oxygenation.

Patients undergoing consideration for venoarterial extracorporeal membrane oxygenation (VA ECMO) require an immediate risk profile assessment in the setting of incomplete or no information. A retrospective cohort study of 100 patients undergoing VA ECMO placement at three institutions was carried out. Variables strongly associated with survival to discharge were used to calculate a risk stratification score. Indications for VA ECMO support included postcardiotomy shock (24%), ischemic etiologies (33%), nonischemic cardiomyopathy (32%), and other etiologies (11%). Pre-VA ECMO arrest occurred in 69%, and 30% of patients underwent cannulation during arrest. Survival to discharge was 38%. Three variables demonstrated a strong trend toward predicting survival to discharge: lactate >10 mmol/L (p = .054), albumin <3 g/dL (p = .062), and platelet count <180 K/uL (p = .064), and these variables were included in a scoring system. The extremes of age and duration of pre-VA ECMO ventilation were associated with a dismal prognosis and were also included. These five variables were used to construct a mortality prediction score. A score of 0 was associated with 10% expected mortality, whereas a score of 4+ was associated with 100% expected mortality. Mortality increased in a stepwise fashion with increasing scores. The expected mortality closely paralleled the observed mortality. A simple scoring system composed of easily collected variables may help predict mortality. However, it is not intended to replace an experienced clinician's judgment, but to enhance it.

Pushing boundaries: Implantation of the 34 mm Medtronic CoreValve in patients with a large aortic annulus.

The relationship between adherence to the recommended CoreValve sizing parameters and clinical outcomes is not well known for the recently released 34 mm valve, which is currently the largest available transcatheter valve. There is a presumed temporal reduction in paravalvular regurgitation in patients who receive an in-range valve, however, certain patients possess annular dimensions that are too large. We therefore describe two patients with annular dimensions larger than the manufacturer recommended range for the 34 mm CoreValve, who despite this underwent transcatheter aortic valve replacement with excellent clinical outcomes.

Aortic Angulation Does Not Impact Outcomes in Self-Expandable or Balloon-Expandable Transcatheter Aortic Valve Replacement.

OBJECTIVES: The role of aortic angulation in attenuating procedural success in balloon-expandable (BE) and self-expandable (SE) transcatheter aortic valve replacement (TAVR) has been controversial. METHODS: We retrospectively assessed patients undergoing SE and BE TAVR who had an aortic angle measured on multidetector computed tomography at a single tertiary referral center. The primary outcome was device success, measured per the Valve Academic Research Consortium-2 criteria. Clinical outcomes at 30 days (including mortality) were also assessed. RESULTS: A total of 251 patients were identified; 182 patients received a BE valve and 69 patients an SE valve. The median aortic angle was 46.8° (range 24.4-70°) in the BE group and 43.3° (range 20-71°) in the SE group. In multivariate logistic regression analysis, aortic angulation did not affect device success. Mortality at 30 days and 12 months and postprocedural clinical outcomes were similarly not associated with aortic angulation. CONCLUSION: In this cohort of patients undergoing BE and SE TAVR over a wide range of aortic angles, we found no associations between angle and device success or any other clinical metrics. Increased aortic angulation does not adversely affect outcomes in BE or SE TAVR.

Use of High-Frequency Percussive Ventilation to Expand Organ Donor Pool.

A 34-year-old woman was brought in to the emergency department after a motor vehicle accident. She had signs of traumatic head injury with Glasgow Coma Scale score of 3, and her neurological examination was consistent with brain death. She was persistently hypoxic on conventional mechanical ventilation and high-frequency percussive ventilation was initiated. The patient's oxygenation improved and was sustained long enough to provide time for organ procurement. This is the first case portraying high-frequency percussive ventilation as a bridge for donors failing on conventional mechanical ventilation.

Endovascular Management of Tracheo-Subclavian Fistula.

Tracheoarterial fistula is a rare complication of tracheostomy with an incidence of less than 1%. Survival of this disease entity is low, and it likely results from a major open operation in a high-risk surgical group. In our review of the literature, a tracheoinnominate artery fistula is the most commonly reported arterial fistula. However, we present a rare case of tracheo-left subclavian artery fistula. We have identified 1 previous case of tracheo-left subclavian fistula as a source of massive tracheal bleeding. In our case report, we describe the successful management of this disease by endograft placement. Owing to its rarity, there are no guidelines on the management approach to tracheoarterial fistulas, but given the difficulty of controlling this problem via median sternotomy, the placement of a covered stent may be the best therapy. Initially, case reports showed a role for endograft placement as a temporizing measure, but the risk of infection may be sufficiently low to justify this approach as a definitive therapy. Upon a 6-month follow-up, our patient remains without recurrence of bleeding or infection, and computed tomography angiography of the chest with 3D reconstruction has shown patency of the endovascular stent with resolution of the associated pseudoaneurysm.

High-Frequency Percussive Ventilation Facilitates Weaning from Extracorporeal Membrane Oxygenation in Adults.

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is an invaluable rescue therapy for patients suffering from cardiopulmonary arrest, but it is not without its drawbacks. There are cases where patients recover their cardiac function, yet they fail to wean to mechanical conventional ventilation (MCV). The use of high-frequency percussive ventilation (HFPV) has been described in patients with acute respiratory failure (RF) who fail MCV. We describe our experience with five patients who underwent VA-ECMO for cardiopulmonary arrest who were successfully weaned from VA-ECMO with HFPV after failure to wean with MCV. Weaning trials of HFPV a day before decannulation or at the time of separation from VA-ECMO were conducted. Primary endpoint data collected include pre- and post-HFPV partial pressures of oxygen (PaO2) and PaO2/FIO2 (P/F) ratios measured at 2 and 24 hours after institution of HFPV. Additional periprocedural data points were collected including length of time on ECMO, hospital stay, and survival to discharge. Four of five patients were placed on VA-ECMO subsequent to percutaneous coronary intervention. One patient had cardiac arrest secondary to RF. Mean PaO2 (44 ± 15.9 mmHg vs. 354 ± 149 mmHg, p < .01) and mean P/F ratio (44 ± 15.9 vs. 354 ± 149, p < .01) increased dramatically at 2 hours after the initiation of HFPV. The improvement in mean PaO2 and P/F ratio was durable at 24 hours whether or not the patient was returned to MCV (n = 3) or remained on HFPV (n = 2) (44 ± 15.9 mmHg vs. 131 ± 68.7 mmHg, p = .036 and 44 ± 15.9 vs. 169 ± 69.9, p < .01, respectively). Survival to discharge was 80%. The data presented suggest that HFPV may be used as a strategy to shorten time on ECMO, thereby reducing the negative effects of the ECMO circuit and improving its cost efficacy.

Distal Perfusion Cannulation and Limb Complications in Venoarterial Extracorporeal Membrane Oxygenation.

The utility of distal perfusion cannula (DPC) placement for the prevention of limb complications in patients undergoing femoral venoarterial (VA) extracorporeal membrane oxygenation (ECMO) is poorly characterized. Patients undergoing femoral VA ECMO cannulation at two institutions were retrospectively assessed. Patients were grouped into those who did and those who did not receive a DPC at the time of primary cannulation. The primary outcome was any limb complication. Secondary outcomes included successfully weaning ECMO and in-hospital mortality. A total of 75 patients underwent femoral cannulation between December 2010 and December 2017. Of those, 65 patients (86.7%) had a DPC placed during primary cannulation and 10 patients (13.3%) did not. Baseline demographics, indications for ECMO, and hemodynamic perturbations were well matched between groups. The rate of limb complications was 14.7% (11/75) for the overall cohort and did not differ between groups (p = .6). Three patients (4%) required a four-compartment fasciotomy for compartment syndrome in the DPC group; no patients without a DPC required fasciotomy. Of the three patients who required a thrombectomy for distal ischemia, two were in the DPC group and one was in the no-DPC group (p = .3). Two patients (2.7%) underwent delayed DPC placement for limb ischemia with resolution of symptoms. The in-hospital morality rate was 59.5% and did not differ between groups (p = .5). Patients in the present study, undergoing femoral VA ECMO without preemptive DPC placement did not experience a higher rate of limb complications. However, the two patients who underwent delayed DPC placement for post-cannulation ischemia experienced resolution of symptoms, suggesting that a DPC may be used as an effective limb salvage intervention.

Electrocardiographic Correlates of Myocardial Injury After Transcatheter Aortic Valve Replacement.

BACKGROUND: Transcatheter aortic valve replacement (TAVR) is associated with several conduction abnormalities and a need for pacemaker placement. The study aim was to describe all electrocardiographic (ECG) changes seen after TAVR, to compare such changes between transapical (TA) and transfemoral (TF) patient cohorts, and to assess their impact on postoperative outcomes. METHODS: Between March 2009 and July 2014, a total of 286 consecutive patients underwent TAVR at the present authors' institution. Perioperative data were collected prospectively, while preoperative and predischarge electrocardiograms were reviewed retrospectively by an independent cardiologist. RESULTS: A greater proportion of TA patients experienced ECG changes than TF patients at the time of discharge (78% versus 42%; p <0.0001), with more intraventricular conduction abnormalities (29% versus 15%; p = 0.006), and a trend towards more frequent atrioventricular block and pacemaker placement. Troponin levels were higher in patients with new ECG changes (4.61ng/ml versus 2.12 ng/ml; p = 0.0009). New intraventricular conduction abnormalities were associated with increased one-year mortality only in the TF subgroup (65% versus 84%; p = 0.028). Six TA patients demonstrated new ECG findings of myocardial infarction, and this was associated with greater 30-day mortality (67% versus 98%; p = 0.012), although none met the clinical criteria for myocardial infarction. CONCLUSIONS: New ECG changes after TAVR, including new conduction abnormalities, were seen more frequently in TA patients. When seen in TF patients, they were associated with decreased survival. ECG findings of new myocardial infarction, seen only in TA patients, were also associated with decreased survival.