Transcatheter closure of a large post-myocardial infarction ventricular septal defect using the GORE cardioform ASD Occluder.

A 49-year-old man presented late with an anterior wall myocardial infarction (MI) status post-primary coronary intervention of the left anterior descending artery that resulted in no reflow of the vessel. The patient was transferred to our institution in cardiogenic shock.

The impact of BMI on arrest characteristics and survival of patients with out-of-hospital cardiac arrest treated with extracorporeal cardiopulmonary resuscitation.

AIM: To assess the impact of body mass index (BMI) on survival to hospital discharge of patients presenting with refractory ventricular fibrillation treated with extracorporeal cardiopulmonary resuscitation. We hypothesize that due to limitations in pre-hospital care delivery, people with high BMI have worse survival after prolonged resuscitation and ECPR. METHODS: This study is a retrospective single-centre study that included patients suffering refractory VT/VF OHCA from December 2015 to October 2021 and had a BMI calculated at hospital admission. We compared the baseline characteristics and survival between patients with obesity (>30 kg/m2) and those without (≤30 kg/m2). RESULTS: Two-hundred eighty-three patients were included in this study, and two-hundred twenty-four required mechanical support with veno-arterial extracorporeal cardiopulmonary membrane oxygenation (VA ECMO). Patients with BMI > 30 (n = 133) had significantly prolonged CPR duration compared to their peers with BMI ≤ 30 kg/m2 (n = 150) and were significantly more likely to require support with VA ECMO (85.7% vs 73.3%, p = 0.015). Survival to hospital discharge was significantly higher in patients with BMI ≤ 30 kg/m2 (48% vs. 29.3%, p < 0.001). BMI was an independent predictor of mortality in a multivariable logistic regression analysis. The four-year mortality rate was low and not significantly different between the two groups (p = 0.32). CONCLUSION: ECPR yields clinically meaningful long-term survival in patients with BMI > 30 kg/m2. However, the resuscitation time is significantly prolonged, and the overall survival significantly lower compared to patients with BMI ≤ 30 kg/m2. ECPR should, therefore, not be withheld for this population, but faster transport to an ECMO capable centre is mandated to improve survival to hospital discharge.

Initial hospital length of stay and long-term survival of patients successfully resuscitated using extracorporeal cardiopulmonary resuscitation for refractory out-of-hospital cardiac arrest.

AIMS: The long-term outcomes of patients treated with extracorporeal cardiopulmonary resuscitation (ECPR) for refractory ventricular tachycardia/ventricular fibrillation (VT/VF) out-of-hospital cardiac arrest (OHCA) remain poorly defined. The purpose of this study was to describe the hospital length of stay and long-term survival of patients who were successfully rescued with ECPR after refractory VT/VF OHCA. METHODS AND RESULTS: In this retrospective cohort study, the length of index admission and long-term survival of patients treated with ECPR after OHCA at a single centre were evaluated. In a sensitivity analysis, survival of patients managed with left ventricular assist device (LVAD) implantation or heart transplantation during the same period was also evaluated. Between 1 January 2016 and 12 January 2020, 193 patients were transferred for ECPR considerations and 160 underwent peripheral veno-arterial extracorporeal membrane oxygenation cannulation. Of these, 54 (33.7%) survived the index admission. These survivors required a median 16 days of intensive care and 24 days total hospital stay. The median follow-up time of the survivors was 1216 (683, 1461) days. Of all, 79.6 and 72.2% were alive at 1 and 4 years, respectively. Most deaths within the first year occurred among the patients requiring discharge to a long-term acute care facility. Overall survival rates at 4 years were similar in the ECPR and LVAD cohorts (P = 0.30) but were significantly higher for transplant recipients (P < 0.001). CONCLUSION: This data suggest that the lengthy index hospitalization required to manage OHCA patients with ECPR is rewarded by excellent long-term clinical outcomes in an expert ECPR programme.

Invasive hemodynamics are equivocal for functional outcomes after MitraClip.

OBJECTIVES: To evaluate invasive hemodynamics in assessing MC therapy success as well as evaluate its effectiveness as a predictor of functional outcomes. BACKGROUND: Mitral regurgitation grade is a poor predictor of functional outcomes after a MitraClip. There is a paucity of data on invasive hemodynamics as a predictor of outcomes. METHODS: Sixty-nine patients underwent MC between 2015 and 2018 at the University of Minnesota Medical Center and were retrospectively analyzed. Invasive hemodynamics were performed before and after device deployment with transesophageal echocardiographic guidance. Statistical analysis was performed using STATA version 16. Student's t test was used for continuous variables and Pearson's chi-squared test for categorical variables. Mann-Whitney test was performed for continuous variables where data were not normally distributed. Logistic and linear regression were used to investigate relationships between variables and outcomes. RESULTS: A total of 69 patients were included in the study. The mean age was 83 (75-87) years and 38 (55%) were male. Eighty-one percentage had >/= NYHA III symptoms. Eighty-seven percentage had severe MR. Pulmonary capillary wedge pressure was 20 (15-24). Overall, there was significant improvement in left atrial pressure including mean left atrial pressure index, MR, and NYHA class after MC (<.001). There was no significant association between invasive hemodynamics (including left atrial mean pressure index or its reduction rate) and functional outcomes (p = NS). MR grade was also not predictive of functional outcomes. CONCLUSION: Left atrial pressure may not be a significant predictor of functional outcomes, and, in isolation, may not be an improvement over MR grade.

Coronary artery disease burden relation with the presentation of acute cardiac events and ventricular fibrillation.

OBJECTIVES: Evaluate the differences in coronary artery disease (CAD) burden between patients with ischemic resuscitated, ischemic refractory VT/VF OHCA events and N/STEMI. BACKGROUND: Refractory out-of-hospital cardiac arrest patients presenting with initial shockable rhythms (VT/VF OHCA) have the highest mortality among patients with acute cardiac events. No predictors of VT/VF OHCA refractoriness have been identified. METHODS: A retrospective cohort design was used to assess baseline characteristics, clinical outcomes, and the angiographic severity of disease among patients with VT/VF OHCA undergoing emergent coronary angiography at the University of Minnesota Medical Center. The Gensini score was calculated for all patients to assess the angiographic burden of CAD. For patients with ischemia-related cardiac arrest, outcomes were further compared to an independent non-OHCA population presenting with N/STEMI. RESULTS: During the study period, 538 patients were admitted after VT/VF OHCA. Among them, 305 presented with resuscitated, and 233 with refractory VT/VF. 66% of resuscitated and 70% of refractory VT/VF had an underlying, angiographically documented, ischemic etiology. Ischemic resuscitated and refractory VT/VF had significant differences in Gensini score, (80.7 ± 3.6 and 127.6 ± 7.1, respectively, p < 0.001) and survival (77.3% and 30.0%, respectively, p < 0.001). Both groups had a higher CAD burden and worse survival than the non-OHCA N/STEMI population (360 patients). Ischemic refractory VT/VF was significantly more likely to present with chronic total occlusion in comparison to both N/STEMI and ischemic resuscitated VT/VF. CONCLUSION: Ischemia-related, refractory VT/VF OHCA has a higher burden of CAD and the presence of CTOs compared to resuscitated VT/VF OHCA and N/STEMI.

Overview of Veno-Arterial Extracorporeal Membrane Oxygenation (VA-ECMO) Support for the Management of Cardiogenic Shock.

Cardiogenic shock accounts for ~100,000 annual hospital admissions in the United States. Despite improvements in medical management strategies, in-hospital mortality remains unacceptably high. Multiple mechanical circulatory support devices have been developed with the aim to provide hemodynamic support and to improve outcomes in this population. Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is the most advanced temporary life support system that is unique in that it provides immediate and complete hemodynamic support as well as concomitant gas exchange. In this review, we discuss the fundamental concepts and hemodynamic aspects of VA-ECMO support in patients with cardiogenic shock of various etiologies. In addition, we review the common indications, contraindications and complications associated with VA-ECMO use.

The Reliability of Fibro-test in Staging Orthotopic Liver Transplant Recipients with Recurrent Hepatitis C.

Background and Aims: Liver biopsy remains the gold standard for staging of chronic liver disease following orthotopic liver transplantation. Noninvasive assessment of fibrosis with Fibro-test (FT) is well-studied in immunocompetent populations with chronic hepatitis C virus infection. The aim of this study is to investigate the diagnostic value of FT in the assessment of hepatic fibrosis in the allografts of liver transplant recipients with evidence of recurrent hepatitis C. Methods: We retrospectively compared liver biopsies and FT performed within a median of 1 month of each other in orthotopic liver transplantation recipients with recurrent hepatitis C. Results: The study population comprised 22 patients, most of them male (19/22), and with median age of 62 years. For all patients, there was at least a one-stage difference in fibrosis as assessed by liver biopsy compared to FT, while for the majority (16/22) there was at least a two-stage difference. The absence of correlation between the two modalities was statistically demonstrated (Mann-Whitney U test, p = 0.01). In detecting significant fibrosis (a METAVIR stage of F2 and above), an FT cut-off of 0.5 showed moderate sensitivity (77%) and negative predictive value (80%), but suboptimal specificity (61%) and positive predictive value (58%). Conclusions: In post-transplant patients with recurrent hepatitis C, FT appears to be inaccurately assessing the degree of allograft fibrosis, therefore limiting its reliability as a staging tool.

Consistent head up cardiopulmonary resuscitation haemodynamics are observed across porcine and human cadaver translational models.

AIM: The objectives were: 1) replicate key elements of Head Up (HUP) cardiopulmonary resuscitation (CPR) physiology in a traditional swine model of ventricular fibrillation (VF), 2) compare HUP CPR physiology in pig cadavers (PC) to the VF model 3) develop a new human cadaver (HC) CPR model, and 4) assess HUP CPR in HC. METHODS: Nine female pigs were intubated, and anesthetized. Venous, arterial, and intracranial access were obtained. After 6 min of VF, CPR was performed for 2 min epochs as follows: Standard (S)-CPR supine (SUP), Active compression decompression (ACD) CPR + impedance threshold device (ITD-16) CPR SUP, then ACD + ITD HUP CPR. The same sequence was performed in PC 3 h later. In 9 HC, similar vascular and intracranial access were obtained and CPR performed for 1 min epochs using the same sequence as above. RESULTS: The mean cerebral perfusion pressure (CerPP, mmHg) was 14.5 ±â€¯6 for ACD + ITD SUP and 28.7 ±â€¯10 for ACD + ITD HUP (p = .007) in VF, -3.6 ±â€¯5 for ACD + ITD SUP and 7.8 ±â€¯9 for ACD + ITD HUP (p = .007) in PC, and 1.3 ±â€¯4 for ACD + ITD SUP and 11.3 ±â€¯5 for ACD + ITD HUP (p = .007) in HC. Mean systolic and diastolic intracranial pressures (ICP) (mmHg) were significantly lower in the ACD + ITD HUP group versus the ACD + ITD SUP group in all three CPR models. CONCLUSION: HUP CPR decreased ICP while increasing CerPP in pigs in VF as well as in PC and HC CPR models. This first-time demonstration of HUP CPR physiology in humans provides important implications for future resuscitation research and treatment.

Role of epinephrine and extracorporeal membrane oxygenation in the management of ischemic refractory ventricular fibrillation: a randomized trial in pigs.

xtracorporeal membrane oxygenation (ECMO) is used in cardiopulmonary resuscitation (CPR) of refractory cardiac arrest. We used a 2×2 study design to compare ECMO versus CPR and epinephrine versus placebo in a porcine model of ischemic refractory ventricular fibrillation (VF). Pigs underwent 5 minutes of untreated VF, 10 minutes of CPR, and were randomized to receive epinephrine versus placebo for another 35 minutes. Animals were further randomized to LAD reperfusion at minute 45 with ongoing CPR versus veno-arterial ECMO cannulation at minute 45 of CPR and subsequent LAD reperfusion. Four-hour survival was improved with ECMO while epinephrine showed no effect.

Early Effects of Prolonged Cardiac Arrest and Ischemic Postconditioning during Cardiopulmonary Resuscitation on Cardiac and Brain Mitochondrial Function in Pigs.

BACKGROUND: Out-of-hospital cardiac arrest (CA) is a prevalent medical crisis resulting in severe injury to the heart and brain and an overall survival of less than 10%. Mitochondrial dysfunction is predicted to be a key determinant of poor outcomes following prolonged CA. However, the onset and severity of mitochondrial dysfunction during CA and cardiopulmonary resuscitation (CPR) is not fully understood. Ischemic postconditioning (IPC), controlled pauses during the initiation of CPR, has been shown to improve cardiac function and neurologically favorable outcomes after 15min of CA. We tested the hypothesis that mitochondrial dysfunction develops during prolonged CA and can be rescued with IPC during CPR (IPC-CPR). METHODS: A total of 63 swine were randomized to no ischemia (Naïve), 19min of ventricular fibrillation (VF) CA without CPR (Untreated VF), or 15min of CA with 4min of reperfusion with either standard CPR (S-CPR) or IPC-CPR. Mitochondria were isolated from the heart and brain to quantify respiration, rate of ATP synthesis, and calcium retention capacity (CRC). Reactive oxygen species (ROS) production was quantified from fresh frozen heart and brain tissue. RESULTS: Compared to Naïve, Untreated VF induced cardiac and brain ROS overproduction concurrent with decreased mitochondrial respiratory coupling and CRC, as well as decreased cardiac ATP synthesis. Compared to Untreated VF, S-CPR attenuated brain ROS overproduction but had no other effect on mitochondrial function in the heart or brain. Compared to Untreated VF, IPC-CPR improved cardiac mitochondrial respiratory coupling and rate of ATP synthesis, and decreased ROS overproduction in the heart and brain. CONCLUSIONS: Fifteen minutes of VF CA results in diminished mitochondrial respiration, ATP synthesis, CRC, and increased ROS production in the heart and brain. IPC-CPR attenuates cardiac mitochondrial dysfunction caused by prolonged VF CA after only 4min of reperfusion, suggesting that IPC-CPR is an effective intervention to reduce cardiac injury. However, reperfusion with both CPR methods had limited effect on mitochondrial function in the brain, emphasizing an important physiological divergence in post-arrest recovery between those two vital organs.

Intracoronary Poloxamer 188 Prevents Reperfusion Injury in a Porcine Model of ST-Segment Elevation Myocardial Infarction.

BACKGROUND: Poloxamer 188 (P188) is a nonionic triblock copolymer believed to prevent cellular injury after ischemia and reperfusion. OBJECTIVES: This study compared intracoronary infusion of P188 immediately after reperfusion with delayed infusion through a peripheral intravenous catheter in a porcine model of ST segment elevation myocardial infarction (STEMI). Cellular and mitochondrial injury were assessed. METHODS: STEMI was induced in 55 pigs using 45 minutes of endovascular coronary artery occlusion. Pigs were then randomized to four groups: control, immediate intracoronary (IC) P188, delayed peripheral P188, and polyethylene glycol (PEG) infusion. Heart tissue was collected after 4 hours of reperfusion. Assessment of mitochondrial function or infarct size was performed. RESULTS: Mitochondrial yield improved significantly with IC P188 treatment compared to control animals (0.25% vs. 0.13%) suggesting improved mitochondrial morphology and survival. Mitochondrial respiration and calcium retention were also significantly improved with immediate IC P188 compared to controls (complex I RCI: 7.4 vs. 3.7 and calcium retention (nmol): 1152 vs. 386). This benefit was only observed with activation of complex I of the mitochondrial respiratory chain suggesting a specific impact of ischemia and reperfusion on this complex. Infarct size and serum troponin I were significantly reduced by immediate IC P188 infusion (infarct size: 13.9% vs. 41.1% and troponin I (µg/L): 19.2 vs. 77.4 µg/L). Delayed P188 and PEG infusion did not provide a significant benefit. CONCLUSIONS: Intracoronary infusion of P188 immediately upon reperfusion significantly reduces cellular and mitochondrial injury after ischemia and reperfusion in this clinically relevant porcine model of STEMI. The timing and route of delivery were critical to achieve the benefit.

The Effect of Head Up Cardiopulmonary Resuscitation on Cerebral and Systemic Hemodynamics.

AIM: Chest compressions during cardiopulmonary resuscitation (CPR) increase arterial and venous pressures, delivering simultaneous bidirectional high-pressure compression waves to the brain. We hypothesized that this may be detrimental and could be partially overcome by elevation of the head during CPR. MEASUREMENTS: Female Yorkshire farm pigs (n=30) were sedated, intubated, anesthetized, and placed on a table able to elevate the head 30° (15cm) (HUP) and the heart 10° (4cm) or remain in the supine (SUP) flat position during CPR. After 8minutes of untreated ventricular fibrillation and 2minutes of SUP CPR, pigs were randomized to HUP or SUP CPR for 20 more minutes. In Group A, pigs were randomized after 2minutes of flat automated conventional (C) CPR to HUP (n=7) or SUP (n=7) C-CPR. In Group B, pigs were randomized after 2minutes of automated active compression decompression (ACD) CPR plus an impedance threshold device (ITD) SUP CPR to either HUP (n=8) or SUP (n=8). RESULTS: The primary outcome of the study was difference in CerPP (mmHg) between the HUP and SUP positions within groups. After 22minutes of CPR, CerPP was 6±3mmHg in the HUP versus -5±3 in the SUP (p=0.016) in Group A, and 51±8 versus 20±5 (p=0.006) in Group B. Coronary perfusion pressures after 22minutes were HUP 6±2 vs SUP 3±2 (p=0.283) in Group A and HUP 32±5 vs SUP 19±5, (p=0.074) in Group B. In Group B, 6/8 pigs were resuscitated in both positions. No pigs were resuscitated in Group A. CONCLUSIONS: The HUP position in both C-CPR and ACD+ITD CPR significantly improved CerPP. This simple maneuver has the potential to improve neurological outcomes after cardiac arrest.

Application of bioengineering modalities in vascular research: evaluating the clinical gain.

Using knowledge gained from bioengineering studies, current vascular research focuses on the delineation of the natural history and risk assessment of clinical vascular entities with significant morbidity and mortality, making the development of new, more accurate predictive criteria a great challenge. Additionally, conclusions derived from computational simulation studies have enabled the improvement and modification of many biotechnology products that are used routinely in the treatment of vascular diseases. This review highlights the promising role of the bioengineering applications in the vascular field.

An overview of the hemodynamic aspects of the blood flow in the venous outflow tract of the arteriovenous fistula.

Upper limb vein aneurysms complicate all types of autogenous arteriovenous fistulae (AVF) and comprise false aneurysms secondary to venipuncture trauma as well as true aneurysms, characterized by dilatation of native veins. The dilatation of a normal vein and the development of a true aneurysm are strongly influenced by local hemodynamic factors affecting the flow in the drainage venous system and are also the target of operative interventions. This review article focuses on the description of these hemodynamic aspects which all physicians involved in the management of dialysis patients should be aware of. Furthermore, it delineates their complicated interactions and also highlights their utility in clinical decision-making and therapeutic management.