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.

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.

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.

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.

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.

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.

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.

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.

Nocardiosis in Heart Transplant Recipients.

Nocardia has emerged as an important opportunistic pathogen, especially in organ transplant recipients. Heart transplant (HT) recipients initially had an especially high rate of Nocardia infection, but this could be reduced by the routine use of cyclosporine. Our objective was to clarify the prevalence and presentation of Nocardiosis in HT recipients in a retrospective cross-sectional analysis.

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.

A case of biventricular failure after pericardial window for large pericardial effusion.

Pericardial tamponade resulting in hemodynamic compromise requiring either pericardiocentesis [Vandyke 1983] or subxiphoid pericardial window has been reported in literature [Armstrong 1984]. There are no large case series, only scattered case reports. Cardiac tamponade is known to affect the diastolic function of the heart but rare reports have documented systolic impairment of the left and right ventricle in the setting of tamponade [Vandyke 1983; Armstrong 1984]. We report a case of a transient biventricular systolic dysfunction in a patient with early cardiac tamponade after surgical drainage of pericardia1 effusion.

The role of extracorporeal membrane oxygenation circulatory support in the 'crash and burn' patient: from implantation to weaning.

PURPOSE OF REVIEW: In advanced cardiogenic shock, early mechanical circulatory support may prevent multiorgan failure and death. In this article, we are describing our experience with extracorporeal membrane oxygenation (ECMO) application. RECENT FINDINGS: Venoarterial ECMO has been used successfully as a therapeutic option for patients with advanced cardiogenic shock and cardiac arrest. SUMMARY: In this review, based on the daily routine of the Hershey group using ECMO for therapy of advanced cardiogenic shock, the application of ECMO is described. The aim is to share our hands-on experience during emergent implantation and to contribute to the knowledge within the field of mechanical circulatory support.

Improved angiographic findings of superficial femoral artery after verapamil injection into the reperfusion cannula of a patient on peripheral venoarterial ECMO.

Limb ischemia is a complication that can occur in patients requiring percutaneously placed venoarterial extracorporeal membrane oxygenation (ECMO). One method used to prevent limb ischemia is the placement of an antegrade catheter into the superficial femoral artery. We describe a case is which the angiographic findings of the superficial femoral artery were improved by the injection of verapamil in a patient with limb ischemia.

Heterotopic heart transplantation: the United States experience.

INTRODUCTION: More than 3 decades have passed since the first heterotopic heart transplantation (HHT) was reported. Nowadays, this surgical technique is used rarely, and only in patients who do not qualify for standard orthotopic heart transplantation (OHT). Current indications mainly comprise refractory pulmonary hypertension and a donor-recipient size mismatch (>20%). The objective of this study was to analyze the United States experience with HHT. PATIENTS AND METHODS: The United Network for Organ Sharing (UNOS) database between 1987 and 2007 was analyzed. Patients who underwent heart transplantation were enrolled in this study. Patients with missing transplant dates or history of retransplantation were excluded. RESULTS: A total of 41,379 patients underwent OHT and 178 HHT; 32,361 and 111 patients, respectively, were enrolled. Overall 1-, 5-, and 10-year survival was significantly (P < .001) better in OHT (87.7%, 74.4%, 54.4%) than HHT patients (83.8%, 59%, 35.1%). Survival in patients with transpulmonary gradients (TPG) >15 mmHg was 86.6 %, 73.3%, and 57.4% in the OHT and 93.8%, 64.8%, and 48.6% in the HHT group (P = .35). Pretransplant criteria (HHT versus OHT) with statistically significant differences (P < .05) were as follows (mean + SD): recipient weight, 78.9 + 19.9 versus 74.1 + 23.4 kg; recipient height, 174.9 + 13.9 versus 168 + 25.1 cm; and TPG 12.1 + 7.2 versus 9.6 + 6.3 mmHg. CONCLUSIONS: The results show that HHT remains a feasible option in a highly selected patient population, with overall good results.

Neurohormonal regulation and improvement in blood glucose control: reduction of insulin requirement in patients with a nonpulsatile ventricular assist device.

BACKGROUND: Heart failure is associated with prolonged stress and inflammation characterized by elevated levels of cortisol and circulating catecholamines. Persistent sympathetic stimulation secondary to the stress of heart failure causes an induced insulin resistance, which creates a need for higher doses of insulin to adequately manage hyperglycemia in this patient population. We hypothesized that cortisol and catecholamine levels would be elevated in end-stage heart failure patients, however, would be reduced after the implantation of a left ventricular assist device (LVAD). Insulin requirements would therefore be reduced post LVAD implant and control of diabetes improved as compared with pre-implant. METHODS: Pre- and postoperative cortisol, catecholamine, glycated hemoglobin, and blood glucose levels were evaluated retrospectively in 99 LVAD patients at a single center from January 2007 through November 2011. Serum was collected before LVAD implantation and monthly after implantation for 12 months consecutively. Results were evaluated and compared to insulin requirements, if any, before and after implant. Plasma levels were measured by ELISA. RESULTS: There were a total of 99 patients (81 men and 18 women). Two patients were implanted twice due to pump dysfunction. Mean age was 59 years, ± 10, with a median of 63 years. Of those patients, 64 had ischemic cardiomyopathy and 35 had dilated cardiomyopathy. The total patient years of LVAD support were 92.5 years. All patients received a continuous flow left ventricular assist device. Type II diabetes mellitus was diagnosed in 28 patients. Of those patients, 24 required daily insulin with an average dose of 45 units/day. Average preoperative glycated hemoglobin (HbA1c) levels were 6.8% with fasting blood glucose measurements of 136 mg/dL. Mean cortisol levels were measured at 24.3 µg/dL before LVAD implantation, with mean plasma catecholamine levels of 1824 µg/mL. Post operatively, average HbA1c levels were 5.38% with fasting blood glucose measurements of 122 mg/dL. Mean cortisol levels were measured at 10.9 µg/dL with average plasma catecholamine levels were 815 µg/mL. There was a significant decrease in both cortisol levels post LVAD implant (P = 0.012) as well as catecholamine levels (P = 0.044). The average insulin requirements post LVAD implant were significantly reduced to 13 units/day (P = 0.001). Six patients no longer required any insulin after implant. CONCLUSION: Implantation of nonpulsatile LVADs has become a viable option for the treatment of end-stage heart failure, helping to improve patient quality of life by decreasing clinical symptoms associated with poor end-organ perfusion. Frequently, diabetes is a comorbid condition that exists among heart failure patients and with the reduction of the systemic inflammatory and stress response produced by the support of a nonpulsatile LVAD, many patients may benefit from a reduction in their blood glucose levels, as well as insulin requirements.