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.

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.

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.

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.

The use of high-frequency percussive ventilation after cardiac surgery significantly improves gas exchange without impairment of hemodynamics.

OBJECTIVE: Respiratory failure represents a significant source of morbidity and mortality for surgical patients. High-frequency percussive ventilation (HFPV) is emerging as a potentially effective rescue therapy in patients failing conventional mechanical ventilation (CMV). Use of HFPV is often limited by concerns for potential effects on hemodynamics, which is particularly tenuous in patients immediately after cardiac surgery. In this manuscript we evaluated the effects of HFPV on gas exchange and cardiac hemodynamics in the immediate postoperative period after cardiac surgery, in comparison with CMV. METHODS: Twenty-four consecutive cardiac surgery patients were ventilated in immediate postoperative period with HFPV for two to four hours, then they switched to a CMV using the adaptive support ventilation mode for weaning. Arterial blood gases were performed during the first and second hour on HFPV, and at 45 minutes after initiation of CMV. Respiratory settings and invasive hemodynamic data (mixed venous oxygen saturation, central venous pressure, systemic and pulmonary blood pressure, cardiac output and index) were collected utilizing right heart pulmonary catheter and arterial lines during HFPV and CMV. Primary outcome was improvement in the ratio between partial pressure of oxygen to fraction of inspired oxygen (P/F ratio) and changes in hemodynamics. RESULTS: Analysis of data for 24 patients revealed a significantly better P/F ratio during the first and second hour on HFPV, compared with a P/F ratio on CMV (420.0 ± 158.8, 459.2 ± 138.5, and 260.2 ± 98.5 respectively, p < 0.05), suggesting much better gas exchange on HFPV than on CMV. Hemodynamics were not affected by the mode of the ventilation. CONCLUSIONS: Improvement in gas exchange, reflected in a significantly improved P/F ratio, wasn't accompanied by worsening in hemodynamic parameters. The significant gains in the P/F ratio were lost when patients were switched to conventional ventilation. This data suggest that HFPV provides significantly better gas exchange compared with CMV and can be safely utilized in postoperative cardiac patients without any significant effect on hemodynamics.

Factors Associated with Successful Thrombus Extraction with the AngioVac Device: An Institutional Experience.

BACKGROUND: The AngioVac (AngioDynamics, Latham, NY) device utilizes a venovenous bypass circuit for percutaneous venous thrombectomy and has been applied in the setting of iliocaval thrombosis as well as right heart thrombus and pulmonary emboli. We describe our experience with the AngioVac device in 12 patients with a variety of indications with the goal of identifying factors correlating with successful thrombectomy. METHODS: From August 2013 to June 2015, 12 patients underwent AngioVac percutaneous thrombectomy at our institution. Preoperative, intraoperative, and postoperative data were retrospectively analyzed. RESULTS: Indications for thrombectomy included iliocaval thrombosis in 33% (4), right heart thrombus in 42% (5), and pulmonary embolus in 25% (3). We experienced a 58% complete success rate. Partial success was achieved in 17%, and no thrombus was extracted in 25%. Iliocaval and right heart thrombi were the most amenable to AngioVac thrombectomy with 100% (4/4) and 60% (3/5) complete success rates, respectively. Pulmonary embolus was the least amenable to thrombectomy with a 33% partial success rate (1/3) and 67% failure rate (2/3). CONCLUSION: The AngioVac devices allow for percutaneous thrombectomy in the setting of iliocaval and right heart thrombus in patients for whom medical therapy fails or for those in whom surgical intervention is considered high risk. Pulmonary emboli are less amenable, likely due to limited steeribility of the device. Larger studies are needed to make more definitive conclusions, and newer iterations of the device will likely allow for improved outcomes.

Cardiac Amyloidosis Presenting With Cardiogenic Shock.

Cardiac amyloidosis is an infiltrative disorder of the myocardium. It is the result of one of 4 types of amyloidosis: primary systemic (immunoglobulin light chain), secondary, familial (hereditary), or senile. Cardiac amyloidosis ultimately causes congestive heart failure due to irreversible restrictive cardiomyopathy. Because of the rapid progression of the disease, early recognition and determination of underlying etiology are important for tailored therapy. Current interventions range from conservative heart failure management to autologous stem cell and heart transplantation. We present a case of cardiac amyloidosis accompanying undiagnosed multiple myeloma to illustrate the rapid progression of the disease and the complexities of diagnosing and treating this disorder.

Transcatheter Aortic Valve Replacement in Type B Aortic Dissection.

Transcatheter aortic valve replacement (TAVR) has become an acceptable alternative to surgical aortic valve replacement in high-risk and inoperable patients. Several technical and anatomical considerations can increase the complexity and risk of the procedure, and therefore are considered as contraindications to TAVR. Patients with significant aortic disease such as aortic dissection are not usually considered for TAVR due to risk of aortic rupture or retrograde extension of the dissection. Herein is presented a report of the first successful TAVR in a patient with extensive type B dissection.

Preoperative hypothyroidism is a risk factor for postoperative atrial fibrillation in cardiac surgical patients.

BACKGROUND AND AIM: Although studies analyzing the effect of thyroid supplementation on postoperative morbidity and mortality from cardiac surgery have been inconclusive, they suggest a role in the prevention of postoperative atrial fibrillation. To further explore this relationship we conducted a retrospective study to determine whether abnormalities in routine preoperative thyroid function studies correlate with the incidence of postoperative atrial fibrillation. METHODS: From May 2004 until July 2011, 821 patients with complete thyroid function testing performed preoperatively underwent cardiac surgery. Preoperative, intraoperative, and postoperative laboratory, clinical and hemodynamic data including postoperative electrocardiogram monitoring were retrospectively evaluated. RESULTS: Mean age was 65.7 years and 36% (294) of patients were female. Mean preoperative ejection fraction was 48.6% and 18% (100) had clinical heart failure. Ninety percent (682) of patients were euthyroid and 10% (77) were hypothyroid. Atrial fibrillation occurred significantly more frequently in hypothyroid patients (33.4% vs. 22.5%; p = .033). In multivariable analysis, increasing thyroid stimulating hormone (TSH) level (OR: 1.11; CI: 1.01 to 1.22; p = .030) was an independent predictor of postoperative atrial fibrillation. Beta blocker use within 24 hours prior to operation was protective (OR: .54; CI: .35 to .83; p = .005). Length of stay was significantly longer in patients with postoperative atrial fibrillation (9.1 vs. 6.5 days; p < .001). CONCLUSIONS: In the current study, preoperative hypothyroidism was associated with postoperative atrial fibrillation. Further studies are warranted to delineate whether preoperative hypothyroidism is a useful biomarker for selecting patients most likely to benefit from preoperative thyroid supplementation in the prevention of postoperative atrial fibrillation.

Extracorporeal Membrane Oxygenation as a Bridge through Chemotherapy in B-Cell Lymphoma.

A 41-year-old female presented with a large anterior mediastinal mass adjacent to the heart. Biopsy demonstrated lymphoma. Upon administration of chemotherapy, she developed cardiogenic shock requiring a 5-day course of extracorporeal membrane oxygenation (ECMO) as a bridge through her treatment. After one cycle of chemotherapy, ECMO was discontinued and the patient completed her course of chemotherapy and recovered to hospital discharge.

Pulmonary embolectomy in the treatment of submassive and massive pulmonary embolism.

OBJECTIVES: Significant improvements in outcomes after pulmonary embolectomy have resulted in a broadening of indications. We reviewed our experience with pulmonary embolectomy over the past 12 years with an emphasis on preoperative comorbidities and postoperative morbidity and mortality. METHODS: All patients undergoing pulmonary embolectomy over the past 12 years at our institution were analyzed via retrospective chart review. Data on preoperative characteristics, operative procedures and postoperative outcomes were collected. RESULTS: Twenty patients underwent pulmonary embolectomy between 1999 and 2011. The average age was 56 years (range 24-81) and 10 patients (50%) were female. All patients demonstrated right ventricular dysfunction and 19 (95%) demonstrated contraindications to thrombolysis. Twelve patients (60%) demonstrated intermittent hypotension, 4 (20%) required intubation and 3 (15%) demonstrated preoperative or intraoperative cardiac arrest. Survival to discharge was 95%. CONCLUSIONS: Pulmonary embolectomy has been shown to be safe and effective in the treatment of massive pulmonary embolism (PE). We achieved a 95% survival rate in a cohort of patients with significant comorbid status. Pulmonary embolectomy should be considered early in the therapeutic algorithm for patients with submassive PE presenting with right ventricular dysfunction to prevent progression. It can also be performed with good outcomes in those already suffering hemodynamic compromise.

Nonoperative Management of Iatrogenic Right Atrial Appendage Pseudoaneurysm During Catheter Ablation.

Atrial pseudoaneurysms are exceedingly rare. Cardiac pseudoaneurysms are at risk for rupture, which may be catastrophic and require emergent thoracotomy for definitive treatment. We report a case of right atrial appendage perforation during catheter ablation leading to tamponade and right atrium pseudoaneurysm.

Venovenous extracorporeal membrane oxygenation for respiratory failure refractory to high frequency percussive ventilation.

BACKGROUND: High frequency percussive ventilation (HFPV) has demonstrated improvements in gas exchange, but not in clinical outcomes. OBJECTIVES: We utilize HFPV in patients failing conventional ventilation (CV), with rescue venovenous extracorporeal membrane oxygenation (VV ECMO) reserved for failure of HFPV, and we describe our experience with such a strategy. METHODS: All adult patients (age >18 years) placed on HFPV for failure of CV at a single institution over a 10-year period were included. Those maintained on HFPV were compared to those that failed HFPV and required VV ECMO. Survival was compared to expected survival after upfront VV ECMO as estimated by VV ECMO risk prediction models. RESULTS: Sixty-four patients were placed on HFPV for failure of CV over a 10-year period. After HFPV initiation, the P/F ratio rose from 76mmHg to 153.3mmHg in the 69 % of patients successfully maintained on HFPV. The P/F ratio only rose from 60.3mmHg to 67mmHg in the other 31 % of patients, and they underwent rescue ECMO with the P/F ratio rising to 261.6mmHg. The P/F ratio continued to improve in HFPV patients, while it declined in ECMO patients, such that at 24 h, the P/F ratio was greater in HFPV patients. The strongest independent predictor of failure of HFPV requiring rescue VV ECMO was a lower pO2 (p = .055). Overall in-hospital survival (59.4 %) was similar to that expected with upfront ECMO (RESP score: 57 %). CONCLUSIONS: HFPV demonstrated significant and sustained improvements in gas exchange and may obviate the need for ECMO and its associated complications.