Converting the Fontan Circulation: Challenges and Evolution.

The Fontan operation, the final palliative step after a series of complex operations in patients with univentricular hearts, has undergone multiple modifications throughout the last decades, with the goal of finding the method which combines the optimal hemodynamic effects of the Fontan circulation with minimal long term side effects. An understanding of the operative evolution and subsequent side effects, as well as the management thereof seems imperative. Since its inception by Francis Fontan the, now obsolete, initial atriopulmonary connection has passed through several milestones into having now reached the era of total cavopulmonary connection. However, recently published results bring to light the new option of biventricular conversion which comes to challenge the management of Fontan patients as we know it. Currently, there is no consensus as to whether to continue with palliation in this challenging group of patients or proceed with heart transplantation. In this collective review, we provide a historic overview of the Fontan evolution as well as future insights, discussing the perspectives of options for patients with failing Fontan, including the latest addition of biventricular correction.

Repair of Bronchial Anastomosis Following Lung Transplantation.

BACKGROUND: Bronchial anastomotic complications are reported in 2 to 18% of patients after lung transplantation. The majority of complications can be managed with bronchoscopic intervention. When extensive dehiscence is present, surgical intervention can be entertained. MATERIALS AND METHODS: Between March 1, 2006, and December 31, 2019, our program performed 244 lung transplantations. We conducted a retrospective review of our patient cohort and identified patients who suffered from significant anastomotic complications that required surgical interventions. RESULTS: Twenty-eight and 216 patients underwent single and bilateral lung transplantations, respectively. Eighteen patients developed airway complications (7.4%). The incidence of anastomotic complications was 5.2% (24 complications for a total of 460 bronchial anastomoses). Four patients were managed conservatively. The majority of the bronchial anastomotic complications were managed endoscopically (eight patients). Four patients with associated massive air leak underwent repair of the bronchial anastomosis and two patients were retransplanted because they developed severe distal airway stenosis. CONCLUSION: Bronchial anastomotic complications are a major cause of morbidity in lung transplantation. The majority of cases can be managed bronchoscopically. In more severe cases associated with massive air leak or imminent massive hemoptysis from bronchopulmonary arterial fistula, surgical intervention is necessary. Aortic homograft interposition along with vascularized pedicle wrapping may be a viable option to re-establish airway continuity when tension-free bronchial anastomotic revision is not possible. In cases with smaller bronchial defects, primary repair with utilization of a vascularized flap can be effective as treatment option.

Utilization of high donor sequence number grafts in cardiac transplantation.

Donor sequence number (DSN) represents the number of candidates to whom a graft was offered and declined prior to acceptance for transplantation. We sought to investigate the outcomes of patients receiving high DSN grafts. Consecutive isolated adult cardiac transplantations performed at a single-center were reviewed. Recipients were grouped into standard (≤75th percentile) DSN and high (>75th percentile) DSN. A previously validated donor risk index was used to quantify the risk associated with donor grafts, and recipient outcomes were assessed. Overall, 254 patients were included: 194 standard DSN (range 1-79) and 60 high DSN (range 82-1723). High DSN grafts were harvested at greater distance (P < .001) with increased ischemia time (P < .001), resulting in a modest increase in donor risk index (1 point median difference, P = .014). High DSN recipients were less frequently listed as UNOS status 1A (P < .001). Despite a nonsignificant trend toward increased in-hospital/30-day mortality in high DSN recipients, there were no differences in primary graft dysfunction or 1-year survival (high DSN 89% vs standard DSN 88%, P = .82). After adjustment for risk factors, high DSN was not associated with increased 1-year mortality (hazard ratio 1.18, 95%-CI 0.54-2.58, P = .68).

HeartMate II Left Ventricular Assist Device Pump Exchange: A Single-Institution Experience.

Background Left ventricular assist devices (LVADs) have revolutionized the treatment of patients with end-stage heart failure. These devices are replaced when pump complications arise if heart transplant is not possible. We present our experience with HeartMate II (HMII (Thoratec, Plesanton, California, United States)) LVAD pump exchange. Materials and Methods We retrospectively reviewed all cases that required pump exchange due to LVAD complication from November 2011 until June 2016 at a single high-volume institution. The indications, demographics, and outcome were extracted and analyzed. Results Of 250 total patients with implanted HMII LVADs, 16 (6%) required pump exchange during the study period. The initial indications for LVAD placement in these patients were bridge to transplantation (n = 6 [37.5%]) or destination therapy (n = 10 [62.5%]). Fifteen patients (93.8%) required pump exchange due to pump thrombosis and 1 (6.2%) due to refractory driveline infection. Nine patients (56.2%) underwent repeat median sternotomy while a left subcostal approach was used in the remaining seven patients. Fifteen patients (93.7%) survived until hospital discharge. During the follow-up period (median, 155 days), 11 patients remained alive and 4 of these underwent successful cardiac transplantation. Conclusion HMII LVAD pump exchange can be safely performed for driveline infection or pump thrombosis when heart transplantation is not an option.

How to Do It: The Commando Operation for Reconstruction of the Fibrous Skeleton with Double Valve Replacement.

Infiltrative processes that extend into the intervalvular fibrosa, such as infection or calcification, often mandate a complex reconstructive procedure known as the Commando operation. First described less than 20 years ago, this operation is not widely implemented, with experience limited to a few select centers. This report provides a detailed summary of our approach to this intricate procedure.

Treatment Strategies and Outcomes of Right Ventricular Failure Post Left Ventricular Assist Device Implantation: An INTERMACS Analysis.

Right heart failure (RHF) management after left ventricular assist device (LVAD) implantation includes inotropes, right ventricular mechanical support, and heart transplantation. The purpose of this study is to compare different RHF treatment strategies in patients with a magnetically levitated centrifugal LVAD. A total of 6,632 Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) patients from 2013 to 2020 were included. Of which, 769 (69.6%) patients (group 1) were supported with inotropes (≥14 days post-LVAD implantation), 233 (21.1%) patients (group 2) were supported with temporary right ventricular assist device (RVAD) that was implanted during LVAD implant, 77 (7.0%) patients (group 3) with durable centrifugal RVAD implanted during the LVAD implant, and 26 (2.4%) patients (group 4) were supported with RVAD (temporary or permanent), which was implanted at a later stage. Groups 1 and 4 had higher survival rates in comparison with group 2 (hazard ratio [HR] = 0.513, 95% confidence intervals [CIs] = 0.402-0.655, p < 0.001, versus group 1) and group 3 (HR = 0.461, 95% CIs = 0.320-0.666, p < 0.001, versus group 1). Patients in group 3 showed higher heart transplantation rates at 12 and 36 months as compared with group 1 (40.4% and 46.6% vs. 21.9% and 37.4%, respectively), group 2 (40.4% and 46.6% vs. 25.8% and 39.3%, respectively), and group 4 (40.4% and 46.6% vs. 3.8% and 12.0%, respectively). Severe RHF post-LVAD is associated with poor survival. Patients with LVAD who during the perioperative period are in need of right ventricular temporary or durable mechanical circulatory support constitute a group at particular risk. Improvement of devices tailored for right ventricular support is mandatory for further evolution of the field.

The Application of Precision Medicine in Structural Heart Diseases: A Step towards the Future.

The personalized applications of 3D printing in interventional cardiology and cardiac surgery represent a transformative paradigm in the management of structural heart diseases. This review underscores the pivotal role of 3D printing in enhancing procedural precision, from preoperative planning to procedural simulation, particularly in valvular heart diseases, such as aortic stenosis and mitral regurgitation. The ability to create patient-specific models contributes significantly to predicting and preventing complications like paravalvular leakage, ensuring optimal device selection, and improving outcomes. Additionally, 3D printing extends its impact beyond valvular diseases to tricuspid regurgitation and non-valvular structural heart conditions. The comprehensive synthesis of the existing literature presented here emphasizes the promising trajectory of individualized approaches facilitated by 3D printing, promising a future where tailored interventions based on precise anatomical considerations become standard practice in cardiovascular care.

Lung Transplantation for the Treatment of Vaping-Induced, Irreversible, End-Stage Lung Injury.

Recently, there has been a rise in the incidence of E-cigarette/Vaping-Associated Lung Injury (EVALI) in the United States, mostly involving tetrahydrocannabinol. Current treatment strategies for EVALI are aimed at controlling the inflammatory and infectious causes, in addition to supportive care. Although most patients improve with supportive measures, the long-term pulmonary effects of this illness are still not well defined. This report describes a case of EVALI resulting in progressive, irreversible destruction of the lung parenchyma that was treated with double lung transplantation.

HeartMate 3 left ventricular assist device implant after excision of a large apical aneurysm.

The presence of a left ventricular apical aneurysm may pose a technical challenge during implantation of a left ventricular assist device (LVAD). We describe implantation of a HeartMate III LVAD under cardioplegic arrest. A ventricular aneurysmectomy was performed and the LVAD was implanted at the left ventricular apex at the level of the transition zone between the scar tissue and the viable myocardium. Two pursestring 2-0 Prolene Fontan sutures were placed circumferentially at the transition zone to make up for the size discrepancy between the left ventricular opening and the HeartMate 3 pump. The echocardiographic analysis demonstrated optimal inflow cannula orientation, and the patient had an uneventful recovery.

Outcomes based on blood pressure in patients on continuous flow left ventricular assist device support: An Interagency Registry for Mechanically Assisted Circulatory Support analysis.

BACKGROUND: An optimal blood pressure (BP) range to mitigate morbidity and mortality on left ventricular assist device (LVAD) support has not been clearly defined. METHODS: Average Doppler opening pressure, mean arterial pressure (MAP), and/or systolic blood pressure (SBP) were calculated in operative survivors (n = 16,155) of LVAD support in the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS). BP distributions were used to group patients into low (BP <25th percentile), normal (25-75th percentile), high (75th-95th percentile), and very high (>95th percentile). Associations between BP and adverse events were evaluated using Cox regression (hazard ratio[HR], 95% confidence interval). RESULTS: The median (25th, 75th) MAP, Doppler, and SBP (mm Hg) during continuous flow LVAD support were 84 (77, 90), 85 (80, 92), and 99 (90, 107) mm Hg, respectively. BP had a bimodal risk association with survival. At 3 years, survival was 58% ± 1.8% in those with low MAP (≤75 mm Hg) vs 70% ± 0.9%, 71% ± 1.5%, and 63% ± 3.0% in the those with normal, high, or very high average MAP, respectively. Patients with chronically low MAP (≤75 mm Hg), Doppler (≤80 mm Hg), and SBP (<90 mm Hg) had 35%-42% higher adjusted hazards of death than patients with normal or high BP (p ≤ 0.0001). Patients with MAP >100 mm Hg, Doppler ≥105 mm Hg, and SBP ≥120 mm Hg had 17%-20% higher adjusted hazards of death than those with normal pressures (p < 0.05). In patients on axial flow LVADs, elevated SBP (HR 1.08 [95% confidence interval, 1.04-1.13] per 10 mm Hg increase) but not MAP correlated with increased incident of stroke. CONCLUSIONS: In INTERMACS, BP extremes during LVAD support increase the risk for adverse events, supporting a MAP goal >75 mm Hg and <90 mm Hg. Hypotension conferred the highest risk for mortality. Excessive BP control should be avoided, and Doppler opening pressure should not be assumed to represent MAP in all patients.

Novel Cardiac Coordinate Modeling System for Three-Dimensional Quantification of Inflow Cannula Malposition of HeartMate II LVADs.

Optimal function of left ventricular assist devices (LVADs) depends on proper alignment of the inflow cannula (IC). Quantitative guidelines for IC angulation are lacking because of variation in cardiac geometry and difficulty in analyzing three-dimensional (3D) cannula orientation relative to the left ventricle (LV). Based on contrast-enhanced computed tomography images from five normal and five clinically malpositioned IC cases in patients with HeartMate II LVADs, we developed a method for 3D quantification of IC malpositioning. Using Mimics image software (Materialise, Leuven, Belgium), the native heart, major arteries, and LVAD were segmented to create patient-specific 3D models, allowing LV cavity volume and long-axis length to be measured directly. The deviation of the IC was quantified in a cylindrical coordinate system at the IC insertion point relative to the mitral valve and septum, and IC occlusion was assessed by the distance between cannula inlet and the proximal endocardium. Compared with normal cases, patients with malpositioned pumps had shorter LV length (p = 0.03) and reduced pump pocket depth (p = 0.009). Malpositioned pumps may experience greater obstruction by the nearby myocardium. This quantitative 3D modeling tool may help identify different modes of pump malalignment and migration and may facilitate preoperative planning and minimally invasive approaches via virtual LVAD implantation.

Reoperative sternotomy is associated with primary graft dysfunction following heart transplantation.

OBJECTIVES: Prior sternotomy is associated with increased morbidity and mortality following heart transplantation. However, its effect on primary graft dysfunction (PGD), a major contributor to early mortality, is unknown. Herein, this effect is studied using the International Society for Heart and Lung Transplantation consensus definition for PGD. METHODS: Medical records of consecutive adult cardiac transplants between 2012 and 2016 were reviewed. Baseline characteristics, postoperative findings and 1-year survival were compared between patients with and without prior sternotomy. RESULTS: Among 255 total patients included, 139 (55%) had undergone prior sternotomy; these recipients were older, more often male, had higher body mass index, higher frequencies of united network for organ sharing (UNOS) 1A status and ischaemic cardiomyopathy and experienced longer waitlist times when compared with those without prior sternotomy (all P < 0.018). Postoperatively, the prior sternotomy group exhibited higher rates of mild to severe PGD (32% vs 18%; P = 0.015) and higher short-term mortality (P = 0.017) and 1-year mortality (P = 0.047). They required more blood transfusions, had more postoperative pneumonia, wound infection and longer hospital stays. A stepwise multivariable regression model identified prior sternotomy as a predictor of PGD (odds ratio 2.7). Multiple prior sternotomies was associated with even more UNOS 1A status, ischaemic cardiomyopathy and pneumonia. However, logistic modelling did not show a difference in the rate of PGD between those with 1 or ≥2 prior sternotomies. CONCLUSIONS: Our data suggest that prior sternotomy is a risk factor for PGD. Consistent with previous reports, prior sternotomy is associated with increased morbidity, blood product utilization and 1-year mortality following cardiac transplantation.

Right atrial thrombus and its causes, complications, and therapy.

A 70-year-old man who presented with dyspnea and intermittent chest pain was found to have a large free-floating right atrial thrombus on two-dimensional echocardiogram. Atriotomy was performed, and an 18-cm-long thrombus was removed from the right atrium and inferior vena cava. Postoperatively, the patient developed cardiogenic shock treated by intravenous vasopressor agents and extracorporeal membrane oxygenation. The postoperative course was also complicated by bilateral pulmonary emboli requiring pulmonary artery thrombectomy. Right atrial thrombus is an underdiagnosed condition with a high mortality rate. The best management modality has not yet been established.

Application of the International Society for Heart and Lung Transplantation (ISHLT) criteria for primary graft dysfunction after cardiac transplantation: outcomes from a high-volume centre†.

OBJECTIVES: A standardized definition for primary graft dysfunction (PGD) after cardiac transplantation was recently proposed by the International Society of Heart and Lung Transplantation (ISHLT). We sought to characterize the outcomes associated with and identify risk factors for PGD following cardiac transplantation using these criteria at a high volume centre. METHODS: Donor and recipient medical records of 201 consecutive adult cardiac transplantations performed between November 2012 and March 2015 were retrospectively reviewed. Patients undergoing isolated heart transplantation were diagnosed with none, mild, moderate, or severe PGD using ISHLT criteria. Cumulative survival was calculated according to the Kaplan­Meier method. Associations of risk factors for combined moderate/severe PGD were assessed with univariate and multivariate analyses. RESULTS: A total of 191 consecutive patients underwent isolated heart transplantation, and 59 (30%) met ISHLT criteria for PGD: 35 (18%) mild, 8 (4%) moderate and 16 (8%) severe. Thirty-day/in-hospital mortality occurred in six (3%) patients, all of whom were diagnosed with severe PGD. Patients with moderate/severe PGD also had significantly increased intensive care unit length of stay (LOS), total LOS, reoperations for bleeding and postoperative infections. Survival at 1-year was diminished with increasing severity of PGD (none 93%, mild 94%, moderate 75% and severe 44%; log-rank P < 0.001). Elevated preoperative creatinine, pretransplantation hospitalized recipient and undersized donor were independently predictive of moderate/severe PGD. CONCLUSIONS: A diagnosis of PGD portends worse outcomes including increased 30-day and 1-year mortality. The ISHLT diagnostic criteria for moderate and severe PGD identify and discriminate patients with PGD in a clinically relevant manner.

Ambulatory extracorporeal membrane oxygenation with subclavian venoarterial cannulation to increase mobility and recovery in a patient awaiting cardiac transplantation.

Venoarterial extracorporeal membrane oxygenation (ECMO) can provide temporary cardiopulmonary support for patients in hemodynamic extremis or refractory heart failure until more durable therapies-such as cardiac transplantation or a left ventricular assist device-can be safely implemented. Conventional ECMO cannulation strategies commonly employ the femoral artery and vein, constraining the patients to the supine position for the duration of ECMO support. We have recently adopted a modified cannulation approach to promote patient mobility, rehabilitation, and faster recovery and to mitigate complications associated with femoral arterial cannulation, such as limb ischemia and compartment syndrome. This technique involves cannulation of the subclavian artery and vein. The current case report details our recent experience with this approach in a critically ill patient awaiting cardiac transplantation.

Comparison of Outcomes of Operative Therapy for Acute Type A Aortic Dissections Provided at High-Volume Versus Low-Volume Medical Centers in North Texas.

Immediate surgery is standard therapy for acute type A aortic dissections (TAAD). Because of its low incidence, many smaller cardiac surgery programs do not routinely perform this procedure because it may negatively affect outcomes. Many high-risk, low-volume (LV) surgical procedures are now preferentially performed in reference centers. We compared the outcomes of surgery for TAAD in high-volume (HV) and LV centers in a single metropolitan area to determine the optimal setting for treatment. Thirty-five of the 37 cardiac surgery programs in the Dallas Ft. Worth metropolitan area participate in a regional consortium to measure outcomes collected in the Society of Thoracic Surgeons Adult Cardiac Database. From January 01, 2008, to December 31, 2014, 29 programs had treated TAAD. Those programs performing at least 100 operations for TAAD were considered HV centers and the others LV. Surgery for TAAD was performed in 672 patients over the 7-year study period with HV centers performing 469 of 672 (70%) of the operations. Despite similar preoperative characteristics, operative mortality was significantly lower in HV versus LV centers (14.1% vs 24.1%; p = 0.001). There was no significant difference in postoperative paralysis rates (2.6% vs 4.5%; p = 0.196), stroke rates (10.7% vs 9.4%; p = 0.623), or 30-day readmission rates (12.1% vs 15.5%; p = 0.292). An improved survival rate in HV centers was maintained over a 5-year follow-up period. Surgery for TAAD in a single large metropolitan area was most commonly performed in HV centers. In conclusion, the treatment of acute thoracic aortic dissection is recommended to be performed in reference centers because of lower early and midterm mortality.

Impact of donor age on cardiac transplantation outcomes and on cardiac function.

OBJECTIVES: Although the impact of older donors on heart transplant outcomes has been previously published, the survival results are conflicting. We herein analyse the impact of older donors on transplant survival and myocardial function. METHODS: The records of the patients who underwent heart transplant at Baylor University Medical Center at Dallas from November 2012 until March 2015 were reviewed and the data were extracted. The heart recipients were divided into two groups based on donors age; 50 years of age was the division point. The two groups were compared with regard to the following transplant outcomes: in-hospital and 1-year survival, severe (3R) rejection, primary graft dysfunction, myocardial performance as reflected by the inotropic score, left ventricular ejection fraction, intensive care unit and overall length of stay. RESULTS: Anoxia was more common cause of death in younger donors (43.9%), whereas intracranial bleeding was more frequent in older donors (48.1%, P = 0.016). The in-hospital survival and 1-year survival were the same between the two groups. Additionally, cardiac transplantation from older donors was not associated with higher incidence of graft dysfunction, higher inotropic support score, longer intensive care unit and total hospital length of stay or more frequent severe rejection episodes. The left ventricular ejection fraction was similar between the two groups. CONCLUSIONS: Heart transplant from older donors is not associated with lower in-hospital and mid-term survival if donors are carefully selected; furthermore, the graft function is comparable. The use of hearts from donors older than 50 years of age can be expanded beyond critically ill recipients in carefully selected recipients.

Using extracorporeal membrane oxygenation support preoperatively and postoperatively as a successful bridge to recovery in a patient with a large infarct-induced ventricular septal defect.

Rupture of the ventricular septum during acute myocardial infarction usually occurs within the first week. The event is usually followed by low cardiac output, heart failure, and multiorgan failure. Despite the many advances in the nonoperative treatment of heart failure and cardiogenic shock, including the intra-aortic balloon pump and a multitude of new inotropic agents and vasodilators, these do not supplant the need for operative intervention in these critically ill patients. This article describes the successful use of extracorporeal membrane oxygenation support as a bridge to recovery postoperatively in a patient with a large infarct-produced ventricular septal defect.