The novel ProtekDuo ventricular assist device: Configurations, technical aspects, and present evidence.

The ProtekDuo, single site dual lumen cannula can be used in a multitude of configurations. In the medical literature, the ProtekDuo is described as right ventricular assist device (RVAD), as left ventricular assist device (LVAD), as biventricular assist device (BiVAD) when combined with an Impella device or other LVAD's, as double lumen drainage cannula on cardiopulmonary bypass (CPB), as RVAD with oxygenator, in veno-pulmonary (V-P) ECMO configuration, venovenous-pulmonary (VV-P) ECMO configuration with additional drainage cannula, and in veno-venopulmonary (V-VP) ECMO configuration as double lumen return cannula. Improvements in flow and oxygenation have been recognized in various settings and need further scientific evaluation. We summarized the above-mentioned configurations, technical aspects, and the present literature available for the ProtekDuo.

The ProtekDuo as double lumen return cannula in V-VP ECMO configuration: A first-in-man method description.

We present a case of acute respiratory distress syndrome (ARDS) secondary to COVID-19 who required venovenous extracorporeal membrane oxygenation (V-V ECMO). Initially, a right ventricular assist device (RVAD), the ProtekDuo with an oxygenator, was placed in an outside heart center and the patient was transferred to us for ECMO management. Due to severe hypoxia, the configuration was later modified, and a 25 Fr femoral drainage cannula was inserted for venous drainage only. The arterial return tubing was spliced and using a Y-connector, arterialized blood was returned through both limbs of the ProtekDuo resulting in a significantly increased oxygenation and flow.

Use of a novel bicarbonate-based Impella 5.5 purge solution in a coagulopathic patient.

The Impella 5.5 with Smart Assist (Abiomed) is a life-saving treatment option in acute heart failure which utilizes a continuous heparin purge solution to prevent thrombosis. In patients with contraindications to heparin, alternative anticoagulation strategies are required. We describe the stepwise management of anticoagulation in a coagulopathic patient with persistent cardiogenic shock following a coronary artery bypass procedure who underwent Impella 5.5 placement. A direct thrombin inhibitor-based purge solution was utilized while evaluating for heparin-induced thrombocytopenia. The use of a novel bicarbonate-based purge solution (BBPS) was successfully used due to severe coagulopathy. There were no episodes of pump thrombosis or episodes of severe bleeding on the BBPS and systemic effects of alkalosis and hypernatremia were minimal.

Veno-arteriovenous extracorporeal membrane oxygenation-A single center experience.

BACKGROUND: Patients with combined circulatory shock and respiratory failure may benefit from veno-arteriovenous (V-AV) extracorporeal membrane oxygenation support (ECMO). We report our center's experience with V-AV ECMO and propose an algorithm to help identify patients that may benefit from early V-AV ECMO support. METHODS: Clinical data were extracted from electronic medical records between November 1, 2016 and November 1, 2019. RESULTS: Out of a total of 369 patients placed on extracorporeal life support (ECLS), we identified a total of 26 patients who underwent hybrid ECMO placement. Three patients were excluded from our analysis due to veno-venoarterial extracorporeal membrane oxygenation (V-VA ECMO) configuration, therefore 23 patients were included in our analysis. The median age was 53 (range 25-73) years. Hybrid ECMO support was instituted most commonly for differential hypoxemia in patients on venoarterial (V-A) ECMO support, and cardiogenic shock in patients who were initially started on venovenous (V-V) ECMO. The initial ECMO cannulation was V-A in 12 patients, V-V in 8 patients, and directly V-AV in 3 patients. Nine out of 23 patients were successfully decannulated (39.1%) and survived until hospital discharge. The main ECMO-related complications included bleeding (n = 10), circuit exchange either due to hemolysis or oxygenator failure (n = 4), ECMO cannula site infection (n = 2), deep venous thrombosis (n = 2), and death during ECMO cannula exchange (n = 1). CONCLUSIONS: V-AV ECMO represents a rescue strategy in critically ill patients with combined respiratory failure and cardio-circulatory shock.

Mechanical cardiopulmonary resuscitation for venoarterial ECMO implantation in pulmonary embolism complicated by type B aortic dissection and retroperitoneal hemorrhage.

A patient with acute pulmonary embolism suffered cardiac arrest, received manual and mechanical cardiopulmonary resuscitation and tissue plasminogen activator before extracorporeal cardiopulmonary resuscitation was initiated. She suffered a type B aortic dissection and retroperitoneal hemorrhage secondary to resuscitation measures. This case report describes high-risk anticoagulation management for contradicting treatment goals in preparation for pulmonary embolectomy on cardiopulmonary bypass.

Successful venoplasty of superior vena cava stenosis in a patient with a total artificial heart after orthotopic heart transplantation due to primary graft failure.

BACKGROUND: With the limited number of available suitable donor hearts resulting in plateaued numbers of heart transplantations, short- and long-term mechanical circulatory support devices, including the implantation of total artificial hearts (TAHs) are modalities that are increasingly being used as treatment options for patients with end-stage heart failure. The superior vena cava syndrome has been described in this context in various disease processes. We report successful venoplasty for superior vena cava syndrome in a patient with a TAH. CASE PRESENTATION: A 65-year-old man with a history of nonischemic cardiomyopathy had received a left ventricular assist device, and then 2 years later, underwent orthotopic heart transplantation using the bicaval anastomosis technique. The postprocedural course was complicated by primary graft failure, resulting in the need for implantation of a TAH. About 5 months after TAH implantation, he started to develop complications such as volume retention, swelling of the upper extremities, and was diagnosed to have a superior vena cava syndrome. The patient underwent a successful venoplasty of his superior vena cava by interventional radiology with resolution of upper body edema, normalization of renal, and liver function. CONCLUSION: Potential fatal complications caused by catheter or wire entrapment in the right-sided mechanical valve of a TAH have been reported. We describe a safe method for the treatment of superior vena cava syndrome in patients with TAH.

Detection of myocardial ischemia due to clinically asymptomatic coronary artery stenosis at rest using supervised artificial intelligence-enabled vectorcardiography - A five-fold cross validation of accuracy.

BACKGROUND: Coronary artery disease (CAD) is a leading cause of death and disability. Conventional non-invasive diagnostic modalities for the detection of stable CAD at rest are subject to significant limitations: low sensitivity, and personal expertise. We aimed to develop a reliable and time-cost efficient screening tool for the detection of coronary ischemia using machine learning. METHODS: We developed a supervised artificial intelligence algorithm combined with a five lead vectorcardiography (VCG) approach (i.e. Cardisiography, CSG) for the diagnosis of CAD. Using vectorcardiography, the excitation process of the heart can be described as a three-dimensional signal. A diagnosis can be received, by first, calculating specific physical parameters from the signal, and subsequently, analyzing them with a machine learning algorithm containing neuronal networks. In this multi-center analysis, the primary evaluated outcome was the accuracy of the CSG Diagnosis System, validated by a five-fold nested cross-validation in comparison to angiographic findings as the gold standard. Individuals with 1, 2, or 3- vessel disease were defined as being affected. RESULTS: Of the 595 patients, 62·0% (n = 369) had 1, 2 or 3- vessel disease identified by coronary angiography. CSG identified a CAD at rest with a sensitivity of 90·2 ± 4·2% for female patients (male: 97·2 ± 3·1%), specificity of 74·4 ± 9·8% (male: 76·1 ± 8·5%), and overall accuracy of 82·5 ± 6·4% (male: 90·7 ± 3·3%). CONCLUSION: These findings demonstrate that supervised artificial intelligence-enabled vectorcardiography can overcome limitations of conventional non-invasive diagnostic modalities for the detection of coronary ischemia at rest and is capable as a highly valid screening tool.

Early prediction of transition to durable mechanical circulatory support in patients undergoing peripheral veno-arterial extracorporeal membrane oxygenation for critical cardiogenic shock.

Peripheral veno-arterial extracorporeal membrane oxygenation (pVA-ECMO) has gained increasing value in the management of patients with critical cardiogenic shock (cCS), allowing time for myocardial recovery. Failure of myocardial recovery has life-altering consequences: transition to durable mechanical circulatory support (dMCS), urgent heart transplantation, or withdrawal of support. Clinical factors controlling myocardial recovery under these circumstances remain largely unknown. Using a retrospective cohort, we developed a model for early prediction of transition to dMCS in patients undergoing pVA-ECMO for cCS. To promote myocardial recovery, our clinical management centered around left ventricular pressure unloading, that is, targeting pulmonary capillary wedge pressures (PCWP) ≤18 mm Hg. We collected demographic data, laboratory findings, inotrope use, and two-dimensional transthoracic echocardiography measurements, all limited to the first 72h of pVA-ECMO (D1-3). Out of 70 patients who were alive after pVA-ECMO, 27 patients underwent implantation of dMCS. There was no significant difference in survival to hospital discharge between patients with or without transition to dMCS. Ejection fractionD1-3 (per 10% increase, OR 0.37 [0.17-0.79]) and amount of inotropic supportD1-3 (OR 4.77 [1.6-14.18]) but neither myocardial wall tension nor PCWP emerged as significant predictors of transition to dMCS. Optimism-corrected c-index (0.90 [0.89-0.90]) revealed an excellent discriminative ability of our model. In summary, our model for early prediction of transition to dMCS in patients with cCS undergoing pVA-ECMO identifies indicators of inotropic state as relevant factors. Absence of markers for myocardial oxygen consumption or left ventricular pressure loading allows us to hypothesize sufficient cardiac unloading in our cohort with PCWP-targeted management.

Percutaneous venoarterial extracorporeal membrane oxygenation as a bridge to double valve implantation in acute biventricular heart failure with profound cardiogenic shock.

A 71-year-old woman was admitted with acute hypoxic and hypercapnic respiratory failure and cardiogenic shock, secondary to acute on chronic biventricular systolic and diastolic congestive heart failure and severe aortic and mitral valve stenosis. She further presented with pulmonary hypertension and moderate-to-severe tricuspid regurgitation requiring high and increasing doses of vasopressors. The patient was percutaneously cannulated for venoarterial extracorporeal membrane oxygenation (VA-ECMO) and stabilized on ECMO, with a urine output of 17.3 L within the following 8 days. Balloon valvuloplasty and/or transcatheter aortic valve replacement were discussed but ruled out by the multidisciplinary team considering the mitral valve could not be fully addressed. Though lung function was not fully optimized, a window of opportunity was identified and used for double valve replacement on day 8 of VA-ECMO support. After a 24-hour vasoplegic period, the patient was extubated to continuous positive airway pressure and further transitioned to nasal cannula, following which she recovered well.

Adult cardiac veno-arterial extracorporeal life support (VA-ECMO): prevention and management of acute complications.

BACKGROUND: Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) has been shown to be a viable and effective treatment for patients suffering from refractory cardiogenic shock (rCS), which is associated with high mortality rates. Although ECMO therapy used as short-term mechanical circulatory support (MCS) has shown tremendous growth in its application over the past decade, the complication and mortality rates remain high. This retrospective study analyzes complications associated with VA-ECMO support, evaluates the use of defined protocols at a single center, and examines factors that may contribute to patient complication and mortality. METHODS: This retrospective analysis included 184 patients who were supported with ECMO from September 2014 through March 2018 at Integris Baptist Medical Center (IBMC). Descriptive statistics were generated to analyze baseline characteristics, demographics, complications, and outcomes. RESULTS: Acute myocardial infarct (AMI) was the primary etiology of this cohort (N=40; 22%). The mean age was 55±15 (median 56, range 15-84) years. All patients were inotrope and/or vasopressor dependent prior to ECMO initiation. Mean time on ECMO support was 7.8±7.9 days with median time of 6 days. Total patient days on support were 1,430. Most ECMO cannulations, 97 (52%) were performed within Integris Baptist Medical Center, with 48% done outside the hospital; 38% were performed outside of the hospital by the IBMC ECMO team, and 10.5% were performed by an outside team. Bleeding was noted to be the most common VA ECMO complication [N=41; 22.3%; 0.028 events per patient day (EPPD)]. CONCLUSIONS: A dedicated 24/7 ECMO service using a multidisciplinary team (MDT) and defined protocols in a single center is able to effectively reduce complications due to VA-ECMO support in the sickest of the sick VA-ECMO patients.

Perspectives on adjunctive use of ketamine for analgosedation during extracorporeal membrane oxygenation.

Analgosedation on ECMO is more than the choice of any drug, it has to be context specific. Ketamine may be considered as an adjunctive therapy in patients requiring high-dose opioids and sedatives during ECMO support with difficulty to achieve a target RASS. Considering ketamine provides analgesia while maintaining airway reflexes, it could be useful for early ECMO weaning and use of ECMO in awake, non-intubated, spontaneously breathing patients with respiratory failure ('awake' ECMO), especially for patients having considerable waiting periods while being bridged to transplant. The hemodynamic effects of ketamine may provide the benefit of decreasing vasopressor requirements, thereby potentially improving microcirculation. In this context, the effects on end-organ function and the need for renal replacement therapy should be investigated. Pharmacokinetic and pharmacodynamic studies on ketamine ex- and in vivo are of utmost importance to delineate its pharmacological profile and effectiveness during ECMO therapy and to create admissible future study hypothesis.

A Weaning Protocol for Venovenous Extracorporeal Membrane Oxygenation With a Review of the Literature.

Several articles have discussed the weaning process for venoarterial extracorporeal membrane oxygenation; however, there is no published report to outline a standardized approach for weaning a patient from venovenous extracorporeal membrane oxygenation (ECMO). This complex process requires an organized approach and a thorough understanding of ventilator management and ECMO physiology. The purpose of this article is to describe the venovenous ECMO weaning protocol used at our institution as well as provide a review of the literature.

Total Artificial Heart Implantation Blood Pressure Management as Resolving Treatment for Massive Hemolysis following Total Artificial Heart Implantation.

The SynCardia Total Artificial Heart (TAH) has been used for patients with biventricular failure, who cannot be managed with implantation of a left ventricular (LV) assist device. Following TAH implantation, our patient developed severe hemolysis, which could only be managed successfully by aggressive blood pressure control [Ohashi 2003; Nakata 1998].

Non-Cardiac Symptoms of Moderate to Severe Hypokalemia in a Patient with a Syncardia™ Total Artificial Heart.

The Syncardia™ total artificial heart (TAH) is an option for patients as a bridge to transplant in those who are not candidates for left ventricular assist devices (LVAD) due to right ventricular failure. Postoperative course is highly dependent on volume status and aggressive diuresis is often necessary. One complication from aggressive diuresis is hypokalemia; however, in these patients we tolerate a lower potassium level because cardiac arrhythmias are not a concern.  However, in two separate instances non-cardiac symptoms related to severe hypokalemia occurred. These symptoms included nystagmus in one patient and agitation, tremors, and having an "out-of-body" experience in the other patient. Both these patients had resolution of symptoms with potassium replacement.

Modified T-Graft for Extracorporeal Membrane Oxygenation in a Patient with Small-Caliber Femoral Arteries.

Extracorporeal membrane oxygenation (ECMO) is generally used as a last resort to provide cardiopulmonary support in patients whose advanced cardiac or respiratory failure does not respond to less invasive treatments. Lower-limb ischemia secondary to the large diameter of the arterial cannula is one of ECMO's major limitations: in patients who have small-caliber arteries, the cannulas can reduce native blood flow. The creation of a T-graft-a well-described technique to avoid limb ischemia-enables flow into the ECMO cannula without jeopardizing blood flow to the limb. However, leaving the graft exposed through an open groin wound can result in dislodgment, and it increases the risk of infection. We describe our modification of a conventional T-graft in an 18-year-old woman who had systolic heart failure, acute respiratory distress syndrome, and small-caliber femoral vessels. We tunneled a polytetrafluoroethylene graft inside a Dacron graft, then ran the combined graft through a subcutaneous tunnel similar to that created for a peripheral bypass. Thus, the graft was protected from environmental exposure and the risk of infection. Our technique seems safer and more secure than the original T-graft technique, and we recommend its consideration during ECMO cannulation.

Steroid treatment resolves acute respiratory failure in patient transferred for ECMO.

INTRODUCTION: Space-consuming mediastinal tumors can create respiratory failure. METHODS: We are reporting on a case of mediastinal lymphoma, which created respiratory failure in our patient. IV steroid therapy was used in our patient, who presented with end-stage respiratory failure. RESULTS: Conservative management of our patient was possible without the application of ECMO. CONCLUSIONS: In the right patient population, IV steroid treatment can avoid further deterioration of end-stage respiratory failure.

Insertion of the Avalon cannula for venovenous extracorporeal membrane oxygenation in a patient with an implanted ASD occlusion device.

Use of the Avalon Elite bicaval dual lumen catheter (Maquet Cardiopulmonary AG, Rastatt, Germany) can be effective in patients requiring venovenous extracorporeal membrane oxygenation (VV-ECMO) for adult respiratory distress syndrome (ARDS). Proper placement of the cannula is important in providing adequate therapy and avoiding life-threatening complications.  We report a case of successful cannulation in a patient with an implanted atrial septal defect (ASD) occlusion device who developed severe refractory ARDS.