Minimally Invasive Mitral Valve Surgery Using a Cold Fibrillatory Cardiac Arrest Technique in Patients With Prior Cardiac Surgery.

OBJECTIVE: Minimally invasive mitral valve surgery (mini-MVS) is typically reserved for patients who have not undergone open cardiac surgery. In the reoperative setting, using intrapericardial dissection for crossclamping the aorta through a minimally invasive approach can be difficult and, at times, risky. Cold fibrillatory cardiac arrest (CFCA) with systemic cardiopulmonary bypass without cross-clamping is a well-described technique; however, data about its safety for patients who undergo reoperative mini-MVS are limited. METHODS: Data for 34 patients who underwent reoperative mini-MVS with CFCA from March 2017 to March 2022 were reviewed retrospectively. A mini right thoracotomy (n = 30) or robotic (n = 4) approach was used. Systemic hypothermia was induced to a target temperature of 25 °C. RESULTS: Patient mean (SD) age was 64.5 (9.6) years, and 15 of 34 (44.1%) patients were women. Of those 34 patients, 23 (67.6%) had severe regurgitation, and 11 (32.4%) had severe stenosis. Before mini-MVS, 28 patients had undergone valve surgery, and 8 had undergone coronary artery bypass graft surgery. The mitral valve was repaired in 5 of 34 (14.7%) and replaced in 29 of 34 (85.3%) patients. No difference was observed in preoperative and postoperative left ventricular function (P = .82). In 1 patient, kidney failure developed that necessitated dialysis. No postoperative stroke or mortality at 30 days occurred. CONCLUSION: Mini-MVS with CFCA is well tolerated in patients with prior cardiac surgery. Myocardial function was not impaired, nor was the risk of stroke increased in this cohort, indicating that CFCA is a safe alternative in this high-risk population.

Predictors and Impact of Prolonged Vasoplegia After Continuous-Flow Left Ventricular Assist Device Implantation.

Background: Vasoplegia after cardiac surgery is associated with adverse outcomes. However, the clinical effects of vasoplegia and the significance of its duration after continuous-flow left ventricular assist device (CF-LVAD) implantation are less known. Objectives: This study aimed to identify predictors of and outcomes from transient vs prolonged vasoplegia after CF-LVAD implantation. Methods: The study was a retrospective review of consecutive patients who underwent CF-LVAD implantation between January 1, 2005, and December 31, 2017. Vasoplegia was defined as the presence of all of the following: mean arterial pressure ≤65 mm Hg, vasopressor (epinephrine, norepinephrine, vasopressin, or dopamine) use for >6 hours within the first 24 hours postoperatively, cardiac index ≥2.2 L/min/m2 and systemic vascular resistance <800 dyne/s/cm5, and vasodilatory shock not attributable to other causes. Prolonged vasoplegia was defined as that lasting 12 to 24 hours; transient vasoplegia was that lasting 6 to <12 hours. Patient characteristics, outcomes, and risk factors were analyzed. Results: Of the 600 patients who underwent CF-LVAD implantation during the study period, 182 (30.3%) developed vasoplegia. Mean patient age was similar between the vasoplegia and no-vasoplegia groups. Prolonged vasoplegia (n = 78; 13.0%), compared with transient vasoplegia (n = 104; 17.3%), was associated with greater 30-day mortality (16.7% vs 5.8%; P = 0.02). Risk factors for prolonged vasoplegia included preoperative dialysis and elevated body mass index. Conclusions: Compared with vasoplegia overall, prolonged vasoplegia was associated with worse survival after CF-LVAD implantation. Treatment to avoid or minimize progression to prolonged vasoplegia may be warranted.

Myocardial edema, inflammation, and injury in human heart donated after circulatory death are sensitive to warm ischemia and subsequent cold storage.

BACKGROUND: Single-dose del Nido solution was recently used in human donation after circulatory death (DCD) heart procurement. We compared the effect of del Nido cardioplegia on myocardial edema, inflammatory response, and injury in human DCD hearts and human donation after brain death (DBD) hearts with different warm ischemic times (WIT) and subsequent cold saline storage times (CST). METHODS: A total of 24 human hearts, including 6 in the DBD group and 18 in the DCD group-were procured for the research study. The DCD group was divided into 3 subgroups based on WIT: 20, 40, and ≥60 minutes. All hearts received 1 L of del Nido cardioplegia before being placed in cold saline for 6 hours. Left ventricular biopsies were performed at 0, 2, 4, and 6 hours. Temporal changes in myocardial edema, inflammatory cytokines (TNF-α, IL-6, and IL-1ß), and histopathology injury scores were compared between the DBD and DCD groups. RESULTS: DCD hearts showed more profound changes in myocardial edema, inflammation, and injury than DBD hearts at baseline and subsequent CST. The DCD heart with WIT of 20 and 40 minutes with CST of 4 and 2 hours, respectively, appeared to have limited myocardial edema, inflammation, and injury. DCD hearts with WIT ≥60 minutes showed severe myocardial edema, inflammation, and injury at baseline and subsequent CST. CONCLUSIONS: Single-dose cold del Nido cardioplegia and subsequent cold normal saline storage can preserve both DCD and DBD hearts. DCD hearts have been shown to be able to tolerate a WIT of 20 minutes and subsequent CST of 4 hours without experiencing significant myocardial edema, inflammation, and injury.

Clinical Predictors and Outcomes After Left Ventricular Assist Device Implantation and Tracheostomy.

BACKGROUND: Postoperative respiratory failure is a major complication that affects up to 10% of patients who undergo cardiac surgery and has a high in-hospital mortality rate. Few studies have investigated whether patients who require tracheostomy for postoperative respiratory failure after continuous-flow left ventricular assist device (CF-LVAD) implantation have worse survival outcomes than patients who do not. OBJECTIVE: To identify risk factors for respiratory failure necessitating tracheostomy in CF-LVAD recipients and to compare survival outcomes between those who did and did not require tracheostomy. METHODS: Consecutive patients who underwent primary CF-LVAD placement at a single institution between August 1, 2002, and December 31, 2019, were retrospectively reviewed. Propensity score matching accounted for baseline differences between the tracheostomy and nontracheostomy groups. Multivariate logistic regression was used to identify tracheostomy risk factors and 90-day survival; Kaplan-Meier analysis was used to assess midterm survival. RESULTS: During the study period, 664 patients received a CF-LVAD; 106 (16.0%) underwent tracheostomy for respiratory failure. Propensity score matching produced 103 matched tracheostomy-nontracheostomy pairs. Patients who underwent tracheostomy were older (mean [SD] age, 57.9 [12.3] vs 54.6 [13.9] years; P = .02) and more likely to need preoperative mechanical circulatory support (61.3% vs 47.8%; P = .01) and preoperative intubation (27.4% vs 8.8%; P < .001); serum creatinine was higher in the tracheostomy group (mean [SD], 1.7 [1.0] vs 1.4 [0.6] mg/dL; P < .001), correlating with tracheostomy need (odds ratio, 1.76; 95% CI, 1.21-2.56; P = .003). Both before and after propensity matching, 30-day, 60-day, 90-day, and 1-year survival were worse in patients who underwent tracheostomy. Median follow-up was 0.8 years (range, 0.0-11.2 years). Three-year Kaplan-Meier survival was significantly worse for the tracheostomy group before (22.0% vs 61.0%; P < .001) and after (22.4% vs 48.3%; P < .001) matching. CONCLUSION: Given the substantially increased probability of death in patients who develop respiratory failure and need tracheostomy, those at high risk for respiratory failure should be carefully considered for CF-LVAD implantation. Comprehensive management to decrease respiratory failure before and after surgery is critical.

The Use of Unilateral Erector Spinae Plane Block in Minimally Invasive Cardiac Surgery.

OBJECTIVES: To examine the efficacy of continuous unilateral erector spinae plane (ESP) blocks in minimally invasive cardiac surgery patients. DESIGN: A retrospective nonrandomized study. SETTING: At a single-center, tertiary academic institution. PARTICIPANTS: The study comprised 129 adult patients undergoing minimally invasive cardiac surgery with cardiopulmonary bypass or extracorporeal membrane oxygenation. INTERVENTIONS: Patient data were retrospectively collected and compared. Group 1 patients received ultrasound-guided ESP blocks, and group 2 patients underwent conventional intraoperative management without ESP blocks. After intubation in the group 1 cohort, 20-to- 25 mL of 0.25% ropivacaine were deposited beneath the erector spinae plane, along with catheter placement for continuous postoperative infusion. MEASUREMENTS AND MAIN RESULTS: Patient characteristics (ie, age, sex, and comorbidities) were well-matched between both cohorts. The total 48-hour opioid consumption, as measured in morphine equivalents (mg), was significantly decreased in patients receiving erector spinae plane blocks compared to patients receiving conventional therapy (30.24 mg ± 23.8 v 47.82 mg ± 53.6, p = 0.04). The length of stay in the intensive care unit (ICU) also was reduced in the treatment group in comparison to the control group (1.99 days ± 1.7 v 2.65 days ± 2.4, p = 0.03). Lastly, patients receiving the blocks benefitted from a decrease in overall hospital length of stay when compared to the control group (5.93 days ± 2.4 v 7.35 days ± 5.8, p = 0.04). CONCLUSION: Erector spinae plane catheter use may safely improve postoperative measures, including decreased opioid consumption and improved pain relief, as well as reductions in ICU and hospital lengths of stay in patients undergoing minimally invasive cardiac surgery.

Peripheral extracorporeal membrane oxygenation support expands the application of robot-assisted coronary artery bypass.

Objective: Robot-assisted coronary artery bypass (RCAB) is typically not offered to higher risk patients with reduced cardiopulmonary function, critical coronary artery disease, and challenging chest wall anatomy. In this study, we report the novel use of nonemergency intraoperative peripheral extracorporeal membrane oxygenation as partial cardiopulmonary support during RCAB for patients who were considered high-risk candidates for conventional CAB and at the same time not eligible for RCAB without cardiopulmonary support. Methods: Forty-five high risk patients (mean age, 68 years; Society of Thoracic Surgeons score, 6.27%; ejection fraction, 45%) underwent RCAB with nonemergency peripheral extracorporeal membrane oxygenation support for the following indications: inability to tolerate single-lung ventilation (n = 17; 38%), low ejection fraction <35% (n = 17; 38%), inadequate exposure of internal thoracic artery (n = 24; 53%), critical coronary artery disease (n = 16; 36%), and hemodynamic instability after anesthesia induction (n = 3; 7%). Following robotic internal thoracic artery takedown, all patients had beating heart minimally invasive direct CAB through a 2-inch minithoracotomy. Results: Up to 30 days, there were no strokes (0%), myocardial infarctions (0%), or access vessel complications (0%). One noncardiac related mortality (2.2%) was related to hemodialysis access issues in a patient with preexisting end-stage renal disease. One redo-CAB (2.2%) patient required sternotomy to locate the target vessel. Thirty-four (75.6%) patients were extubated within 6 hours of surgery. Conclusions: Our results examine the feasibility of using peripheral extracorporeal membrane oxygenation during RCAB for high-risk patients who otherwise had limited options. The use of peripheral extracorporeal membrane oxygenation in RCAB can potentially expand the surgical treatment options in high-risk coronary artery disease patients.

Preoperative hyponatremia and survival after left ventricular assist device implantation.

BACKGROUND: Hyponatremia is associated with adverse outcomes in heart failure and after cardiac surgery. We hypothesized that hyponatremia is associated with poorer short-term and longer term survival in patients after continuous-flow left ventricular assist device (CF-LVAD) placement. METHODS: We reviewed a single-center database of patients who received a CF-LVAD during 2012-2017. Sodium (Na) values obtained within 14 days before CF-LVAD insertion were averaged; patients (n = 332) were divided into hyponatremia (mean Na <135 mEq/L; n = 160; 48.2%) and normonatremia groups (mean Na 135-145 mEq/L; n = 172; 51.8%). Patients requiring preoperative dialysis or pump exchange were excluded. We compared outcomes between preoperative hyponatremia and normonatremia groups. RESULTS: The two groups' baseline characteristics were similar, although hyponatremia patients more often had preoperative mechanical circulatory support (44.4% vs. 31.4%, p = 0.002). Although hyponatremic and normonatremic patients did not differ in 30-day mortality (7.5% vs. 6.5%, p = 0.7), preoperative hyponatremia was associated with greater 5-year mortality (61% vs. 44%, p = 0.03). On binary logistic regression analysis, the strongest independent predictors of late mortality were hyponatremia (odds ratio [OR] 1.88, 95% CI [1.07-3.31], p = 0.02), older age (OR 1.03, 95% CI [1.01-1.05], p = 0.01), and elevated mean right atrial pressure/pulmonary capillary wedge pressure ratio (OR 4.69, 95% CI [1.76-12.47], p = 0.002). CONCLUSIONS: Hyponatremia was not associated with greater early mortality but was associated with poorer late survival. The optimal timing of LVAD implantation in relation to hyponatremia, and whether correcting hyponatremia perioperatively improves long-term survival, should be investigated.

Predictors of renal replacement therapy in patients with continuous flow left ventricular assist devices.

Renal replacement therapy (RRT) after continuous flow left ventricular assist device (CF-LVAD) implantation significantly affects patients' quality of life and survival. To identify preoperative prognostic markers in patients requiring RRT after CF-LVAD implantation, we retrospectively reviewed data from patients who underwent implantation of a CF-LVAD at our institution during 2012-2017. Patients who required preoperative RRT were excluded. Preoperative and operative characteristics, as well as survival and adverse events, were compared between 74 (22.2%) patients requiring any duration of postoperative RRT and 259 (77.8%) not requiring RRT. Patients requiring RRT experienced more postoperative complications than patients who did not, including respiratory failure necessitating tracheostomy (35.7% vs 2.5%, p < 0.001), reoperation for bleeding (34.3% vs 11.7%, p < 0.001), and right heart failure necessitating perioperative mechanical circulatory support (32.4% vs 6.9%, p < 0.001). Patients requiring postoperative RRT also had poorer survival at 30 days (74.7% vs 98.8%), 6 months (48.2% vs 95.1%), and 12 months (45.3% vs 90.2%) (p < 0.001). Significant predictors of RRT after CF-LVAD implantation included urine proteinuria (odds ratio [OR] 3.6, 95% confidence interval [CI] [1.7-7.6], p = 0.001), estimated glomerular filtration rate < 45 mL/min/1.73 m2 (OR 3.4, 95% CI [1.5-17.8], p = 0.004), and mean right atrial pressure to pulmonary capillary wedge pressure ratio ≥ 0.54 (OR 2.6, 95% CI [1.3-5.], p = 0.01). Of the 74 RRT patients, 11 (14.9%) recovered renal function before discharge, 36 (48.6%) still required RRT after discharge, and 27 (36.5%) died before discharge. We conclude that preoperative renal and right ventricular dysfunction significantly predict postoperative renal failure and mortality after CF-LVAD implantation.

Cardiac patient-specific three-dimensional models as surgical planning tools.

BACKGROUND: Three-dimensional printing is an additive manufacturing method that builds objects from digitally generated computational models. Core technologies behind three-dimensional printing are evolving rapidly with major advances in materials, resolution, and speed that enable greater realism and higher accuracy. These improvements have led to novel applications of these processes in the medical field. METHODS: The process of going from a medical image data set (computed tomography, magnetic resonance imaging, ultrasound) to a physical three-dimensional print includes several steps that are described. Medical images originate from Digital Imaging and Communications in Medicine files or data sets, the current standard for storing and transmitting medical images. Via Digital Imaging and Communications in Medicine manipulation software packages, a segmentation process, and manual intervention by an expert user, three-dimensional digital and printed models can be constructed in great detail. RESULTS: Cardiovascular medicine is one of the fastest growing applications for medical three-dimensional printing. The technology is more frequently being used for patient and clinician education, preprocedural planning, and medical device design and prototyping. We report on three case studies, describing how our three-dimensional printing has contributed to the care of cardiac patients at the University of Minnesota. CONCLUSION: Medical applications of computational three-dimensional modeling and printing are already extensive and growing rapidly and are routinely used for visualizing complex anatomies from patient imaging files to plan surgeries and create surgical simulators. Studies are needed to determine whether three-dimensional printed models are cost effective and can consistently improve clinical outcomes before they become part of routine clinical practice.

Impact of 30 Day Readmission After Left Ventricular Assist Device Implantation.

Early readmission (within 30 days) after left ventricular assist device (LVAD) implantation might be a marker for increased mortality. We retrospectively reviewed the records of 277 adults who underwent continuous-flow LVAD implantation from 2005 through 2015 at our institution. The baseline characteristics of patients who were (versus were not) readmitted within 30 days after LVAD implantation were compared. To assess the impact of 30 day readmission on long-term survival, we used multivariate Cox regression. We also compared the cardiac transplant rate between the two groups. Of the 277 patients, 217 (78.3%) underwent LVAD implantation as a bridge-to-transplant; 76 (27.4%) of the 277 were readmitted within 30 days. The most common reason for readmission was volume overload (23.6%), followed by gastrointestinal bleeding (15.8%). Male gender, previous smoking, a higher baseline creatinine level, higher Model for End Stage Liver Disease Excluding INR (MELD-XI) score, and postoperative gastrointestinal bleeding or stroke were each associated with 30 day readmission. In our final multivariate model, increased mortality was also associated with 30 day readmission (hazard ratio, 1.60; 95% confidence interval, 1.1-2.5). Among the 217 bridge-to-transplant patients, the cardiac transplant rate was similar between the two groups: 18.7 transplants per patient-year among those who were readmitted within 30 days versus 19.7 transplants per patient-year among those who were not (p = 0.26). Among our study patients, 30 day readmission after LVAD implantation was frequent and was associated with increased mortality. It is currently unclear whether the general health of those patients was a factor and whether efforts to reduce 30 day readmission would favorably affect longer-term patient outcomes.

Embolization of a complex coronary to pulmonary artery fistula using balloon assisted liquid embolic injection: A novel technique.

Complex Coronary artery to Pulmonary artery fistulas (CPFs) can be difficult to manage with embolization or ligation. An 88-year-old woman with exertional angina was found to have a complex precordial CPF, severe Mitral regurgitation, and Pulmonary Hypertension. CPF treatment was recommended prior to minimally invasive mitral valve replacement (to avoid postoperative myocardial ischemia from worsened steal). The CPF was supplied by multiple branches from the LAD and RCA, and formed a complex common varicosity with multiple drainage channels to the pulmonary artery. The CPF was treated by injecting a liquid embolic agent, Ethylene Vinyl Alcohol Copolymer (Onyx, Medtronic, MN), into two of the feeding arteries arising from the RCA through a Scepter C Dual lumen balloon micro catheter (Microvention, Aliso Viejo, CA. This resulted in complete obliteration of the fistula, and the patient subsequently underwent successful mitral valve replacement surgery.

Impact of Postoperative Liver Dysfunction on Survival After Left Ventricular Assist Device Implantation.

BACKGROUND: Liver dysfunction in left ventricular assist device (LVAD) recipients is common both before and after implantation. Postoperative liver dysfunction (PLD) develops in some LVAD recipients without preoperative liver dysfunction. The aim of this study was to assess clinical outcomes in such patients. METHODS: Records of all patients undergoing implantation of a HeartMate II (HM II, St. Jude Medical, Inc, Minneapolis, MN) LVAD at a single center at the University of Minnesota from January 2005 through June 2014 were analyzed. PLD was defined by hypertransaminasemia or hyperbilirubinemia, or both, during the hospitalization for LVAD implantation. RESULTS: During the study period, 284 patients underwent HM II implantation. Excluded from analysis were 14 recipients with preoperative liver dysfunction. In the final cohort (n = 270), there were no major difference in preoperative characteristics among those patients with versus without PLD. PLD developed in 129 (47.8%) recipients: 16 (12.4%) had isolated hypertransaminasemia (group I), 76 (58.9%) had isolated hyperbilirubinemia (group II), and 37 (28.7%) had combined hypertransaminasemia and hyperbilirubinemia (group III). Group III LVAD recipients had significantly greater rates of 30-day, 90-day, and 1-year mortality, along with significantly higher transfusion requirements and higher rates of renal replacement therapy, prolonged ventilation, and vasopressor use. Moreover, their mortality risk was significantly higher than that of PLD-free LVAD recipients (hazard ratio, 4.6; 95% confidence interval, 2.1 to 10.1; p < 0.001). CONCLUSIONS: Isolated hyperbilirubinemia is common after LVAD implantation. In this study, it was not associated with an increase in early or midterm postoperative mortality. However, postoperative combined transaminasemia and hyperbilirubinemia was associated with a significant increase in early and midterm morbidity and mortality. Further research into the pathogenesis of post-LVAD PLD is necessary.

A Decade of Experience With Continuous-Flow Left Ventricular Assist Devices.

The use of continuous-flow left ventricular assist devices (CF-LVADs) has revolutionized the landscape of mechanical circulatory support for patients with heart failure. Clinical trials are already testing the next generation of CF-LVADs. In this study, our objective was to review our long-term experience with the current generation of CF-LVADs, specifically, the HeartMate (HM) II (Thoratec Corp, Pleasanton, CA). In this single-center retrospective analysis, we evaluated the records of 278 consecutive patients who underwent a total of 302 HM II placements from June 2005 through June 2014. We excluded 11 patients from our final study group, who had previously undergone placement of a HM XVE that failed. We divided the remaining 267 patients into 3 equal groups of 89 patients each, by time period: group 1, June 2005 through May 2009; group 2, June 2009 through January 2012; and group 3, February 2012 through June 2014. To examine differences in survival between our 3 groups, we used time-to-event analysis, including the Kaplan-Meier method. To examine secondary outcomes (including stroke, hemolysis, gastrointestinal bleeding, pump thrombus, and transplant), we used one-way analysis of variance. For our final study group of 267 patients, the total follow-up time was 479.01 patient-years (median, 469 days). The mean age of patients was 57 years; 81.4% were male. In all, 209 (78.9%) patients underwent HM II placement as a bridge to transplant; 58 (21.1%), as destination therapy (DT). The overall survival rate was 94% at 30 days, 77% at 1 year, 65% at 2 years, 60% at 3 years, 50% at 4 years, and 48% at 5 years. In bridge to transplant patients, the survival rate was 78% at 1 year and 66% at 2 years; in DT patients, 70% and 60%. In group 1 patients, the survival rate was 94% at 30 days, 64% at 1 year, and 48% at 2 years; in group 2, 93%, 88%, and 76%; and in group 3, 94%, 77%, and 73% (P = 0.003). In the later years of our study period, from June 2009 onwards (ie, in groups 2 and 3), we noted a statistically significant increase in HM II placement as DT, a reduction of driveline infections, increasing pump exchange, increasing hemolysis, a reduced frequency of transplants, and an improved survival rate (as compared with the earlier group 1). The HM II has favorably influenced the outcomes of patients with end-stage heart failure, yet major complications still limit their survival. Improving compatibility between the pump and the individual host patient, enhancing anticoagulation strategies, and developing a totally implantable pump might further reduce complications thereby improving survival times and allowing CF-LVAD placement to be a true long-term alternative to a heart transplant.

Stroke After Left Ventricular Assist Device Implantation: Outcomes in the Continuous-Flow Era.

BACKGROUND: Left ventricular assist devices (LVADs) are increasingly used in patients with heart failure. To study the impact of stroke on clinical outcomes after continuous-flow (CF-) LVAD implantation, we evaluated our single-center experience. METHODS: From 2006 to 2013, we implanted the HeartMate II CF-LVAD in 230 patients. We used standard statistical methods to evaluate our results. RESULTS: Of our study group, 185 patients (80.4%) received the CF-LVAD as a bridge to transplantation. Strokes occurred in a total of 39 patients (17%), an incidence rate of 0.064 strokes per person-year: 19 (48.7%) were embolic, and 20 (51.3%) were hemorrhagic. The stroke-free rate at 6 months after HeartMate II implantation was 92.6%, at 12 months, 89.6%, and at 24 months, 86.1%. Baseline demographic characteristics did not differ significantly, except that stroke patients had a lower incidence of coronary artery disease (p = 0.004) and prior cardiac surgery (p = 0.001). We noted a trend toward an increased risk of stroke in patients with CF-LVAD-related infections (p = 0.053). The survival rate in stroke (versus stroke-free) patients at 6 months was 84.6% (versus 84.2%); at 12 months, 71.8% (versus 81.6%); and at 24 months, 53.9% (versus 74.7%; p = 0.0019). During a median follow-up time of 761 days, mortality risk in stroke patients was 2.01 times that of stroke-free patients (hazard ratio = 2.01; p = 0.004). CONCLUSIONS: Stroke while on CF-LVAD support was associated with significant mortality. To reduce the risk of stroke, it is essential to further elucidate risk factors, to optimize anticoagulation, and to further understand the impact of LVAD-related infections.

Derivation and high engraftment of patient-specific cardiomyocyte sheet using induced pluripotent stem cells generated from adult cardiac fibroblast.

BACKGROUND: Induced pluripotent stem cells (iPSCs) can be differentiated into potentially unlimited lineages of cell types for use in autologous cell therapy. However, the efficiency of the differentiation procedure and subsequent function of the iPSC-derived cells may be influenced by epigenetic factors that the iPSCs retain from their tissues of origin; thus, iPSC-derived cells may be more effective for treatment of myocardial injury if the iPSCs were engineered from cardiac-lineage cells, rather than dermal fibroblasts. METHODS AND RESULTS: We show that human cardiac iPSCs (hciPSCs) can be generated from cardiac fibroblasts and subsequently differentiated into exceptionally pure (>92%) sheets of cardiomyocytes (CMs). The hciPSCs passed through all the normal stages of differentiation before assuming a CM identity. When using the fibrin gel-enhanced delivery of hciPSC-CM sheets at the site of injury in infarcted mouse hearts, the engraftment rate was 31.91%±5.75% at Day 28 post transplantation. The hciPSC-CM in the sheet also appeared to develop a more mature, structurally aligned phenotype 28 days after transplantation and was associated with significant improvements in cardiac function, vascularity, and reduction in apoptosis. CONCLUSIONS: These data strongly support the potential of hciPSC-CM sheet transplantation for the treatment of heart with acute myocardial infarction.

Hemolysis, pump thrombus, and neurologic events in continuous-flow left ventricular assist device recipients.

BACKGROUND: An ongoing challenge in the management of patients with heart failure who receive left ventricular assist devices (LVADs) is achieving optimal anticoagulation. Adverse prothrombotic events include hemolysis or pump thrombus (H/T) and neurologic events (NEs), and all limit the success of LVAD therapy. Our aim was to study the incidence and clinical outcomes associated with these events in a large single-center cohort. METHODS: We retrospectively reviewed our prospectively collected database of all patients receiving a HeartMate II (Thoratec Corp, Pleasanton, CA) LVAD from 2005 to 2012. Demographic, clinical, and outcome data were analyzed using standard statistical methods. All adverse events were recorded. RESULTS: Of 193 patients receiving LVADs, we identified 39 H/T events in 26 (13.4%) patients and 22 NEs in 19 (9.8%) patients. Seventy-four percent of events occurred in the last 3 years of the series, during which time 63% of implants were placed. Of patients with H/T, 8 (31% of those having H/T, 4.1% of total) had more than 1 event and 4 (15.4% of those having H/T, 2.1% of total) underwent pump exchanges. Five (23%) patients had NEs after H/T, and 6 (32%) died as a result of the NE. Of patients with H/T, 27% had preceding episodes of infection, 31% had an international normalized ratio (INR) of less than 1.5, 31% had an INR of 1.5 to 2, 15% had a history of clotting or were hypercoagulable, and 4% had anticoagulation intentionally withheld. Lactate dehydrogenase (LDH), plasma hemoglobin, INR, and platelet determinations were significantly different at the time of H/T compared with baseline values. The survival at 6 months (alive or having undergone transplantation) for those with a prothrombotic event compared with those without was 70% versus 75.2% (p = 0.5). CONCLUSIONS: The incidence of H/T or NEs is significant and results in major morbidity after LVAD placement. Infection and suboptimal anticoagulation are associated with the majority of these events. Identification of patients at higher risk for hemolysis (ie, infection) may allow for modification of anticoagulation regimens to reduce these risks and improve clinical outcomes.

Benefits and limitations of multimodality imaging in the diagnosis of a primary cardiac lymphoma.

Primary cardiac tumors are far rarer than tumors metastatic to the heart. Angiosarcoma is the primary cardiac neoplasm most frequently detected; lymphomas constitute only 1% of primary cardiac tumors. We present the case of a 55-year-old woman with a recently diagnosed intracardiac mass who was referred to our institution for consideration of urgent orthotopic heart transplantation. Initial images suggested an angiosarcoma; however, a biopsy specimen of the mass was diagnostic for diffuse large B-cell lymphoma. The patient underwent chemotherapy rather than surgery, and she was asymptomatic 34 months later. We use our patient's case to discuss the benefits and limitations of multiple imaging methods in the evaluation of cardiac masses. Certain features revealed by computed tomography, cardiac magnetic resonance, and positron emission tomography can suggest a diagnosis of angiosarcoma rather than lymphoma. Cardiac magnetic resonance and positron emission tomography enable reliable distinction between benign and malignant tumors; however, the characteristics of different malignant tumors can overlap. Despite the great usefulness of multiple imaging methods for timely diagnosis, defining the extent of spread and the hemodynamic impact, and monitoring responses to treatment, we think that biopsy analysis is still warranted in order to obtain a correct histologic diagnosis in cases of suspected malignant cardiac tumors.

Left ventricular outflow tract occluding thrombus after biventricular mechanical circulatory support as a bridge to recovery.

The role of mechanical circulatory support for cardiopulmonary failure is expanding. Anticoagulation in the setting of static blood, hypercoagulable states, extracorporeal circuits, and surgery presents an intricate and delicate balance. We present a patient with large, biventricular thrombi during and succeeding biventricular mechanical support. Management of the thrombi and device selection in this patient are discussed.