The Society of Thoracic Surgeons (STS)-Interagency Registry for Mechanically Assisted Circulatory Support (Intermacs) 2020 Annual Report reviews outcomes on 25,551 patients undergoing primary ...isolated continuous-flow left ventricular assist device (LVAD) implantation between 2010 and 2019. In 2019, 3198 primary LVADs were implanted, which is the highest annual volume in Intermacs history. Compared with the previous era (2010-2014), patients who received an LVAD in the most recent era (2015-2019) were more likely to be African American (26.8% vs 22.9%, P < .0001) and more likely to be bridged to durable LVAD with temporary mechanical support devices (36.8% vs 26.0%, P < .0001). In 2019, 50% of patients were INTERMACS Profile 1 or 2 before durable LVAD, and 73% received an LVAD as destination therapy. Magnetic levitation technology has become the predominant design, accounting for 77% of devices in 2019. The 1- and 2-year survival in the most recent era has improved compared with 2010 to 2014 (82.3% and 73.1% vs 80.5% and 69.1%, respectively; P < .0001). Major bleeding and infection continue to be the leading adverse events. Incident stroke has declined in the current era to 12.7% at 1 year. STS-Intermacs research publications are highlighted, and the new quality initiatives are introduced.
Display omitted
Small-scale solar thermal cogeneration shows promise as an effective way to get increased benefit out of a given solar availability, since it does not waste potential during summer after the water ...capacity is heated. In this paper a scroll expander is tested in a small organic Rankine cycle (ORC) and used to calibrate a static expander model. Validation of the scroll expander model shows agreement generally within 10% for the shaft power, 5% for the rotational speed and 6 K for the exhaust temperature, with some outliers at very low pressure ratios. This calibrated model is then incorporated into a larger dynamic model of a solar thermal cogeneration system, designed for some larger dwelling unit or small commercial establishment that requires a larger volume of hot water. An annual simulation is conducted using a collector area of 50 m2, and the scroll expander shows a maximum isentropic efficiency of 59% while the ORC efficiency is 3.47%. The total energy produced is 1710 kWh and the hot water available is on average 2540 L/day. The maximum instantaneous power that can be produced by the system is 676 W, and it is possible to shift the time period that the system is producing power to match the peak demand period by adjusting the solar store volume.
► A scroll expander is modelled and parameter values are estimated experimentally. ► The scroll expander shows a maximum isentropic efficiency of 59%. ► A dynamic model of a low-cost solar thermal cogeneration system is presented. ► The cycle thermal efficiency is 3.47%. ► 1710 kWh electricity is produced per year as a by-product of heating water.
Prenatal diagnosis allows improved perioperative outcomes for fetuses with certain forms of congenital heart disease (CHD). Variability in prenatal diagnosis has been demonstrated in other countries, ...leading to efforts to improve fetal imaging protocols and access to care, but has not been examined across the United States. The objective was to evaluate national variation in prenatal detection across geographic region and defect type in neonates and infants with CHD undergoing heart surgery.
Cardiovascular operations performed in patients ≤6 months of age in the United States and included in the Society of Thoracic Surgeons Congenital Heart Surgery Database (2006-2012) were eligible for inclusion. Centers with >15% missing prenatal diagnosis data were excluded from the study. Prenatal diagnosis rates were compared across geographic location of residence and defect type using the χ(2) test.
Overall, the study included 31,374 patients from 91 Society of Thoracic Surgeons Congenital Heart Surgery Database participating centers across the United States. Prenatal detection occurred in 34% and increased every year, from 26% (2006) to 42% (2012). There was significant geographic variation in rates of prenatal diagnosis across states (range 11.8%-53.4%, P < .0001). Significant variability by defect type was also observed, with higher rates for lesions identifiable on 4-chamber view than for those requiring outflow tract visualization (57% vs 32%, P < .0001).
Rates of prenatal CHD detection in the United States remain low for patients undergoing surgical intervention, with significant variability between states and across defect type. Additional studies are needed to identify reasons for this variation and the potential impact on patient outcomes.
Background Perioperative advances have led to significant improvements in outcomes after many complex neonatal open heart procedures. Whether similar improvements have been realized for the modified ...Blalock-Taussig shunt, the most common palliative neonatal closed-heart procedure, is not known. Methods Data were abstracted from The Society of Thoracic Surgeons Congenital Heart Surgery Database (2002 to 2009). Inclusion criteria were all neonates who received a modified Blalock-Taussig shunt with or without cardiopulmonary bypass, and with or without concomitant ligation of a patent ductus arteriosus. Discharge mortality was the primary end point. A composite morbidity end point one or more of the following: postoperative extracorporeal membrane oxygenation, low cardiac output, or unplanned reoperation. Associations with patient and procedural variables were assessed with univariable and multivariable analyses. Results The inclusion criteria were met by 1273 patients. The discharge mortality rate was 7.2%, and composite morbidity, as defined, was 13.1%. Primary diagnoses were classified as (1) those potentially amenable to biventricular repair (62%), (2) functionally univentricular hearts (22%), and (3) pulmonary atresia with intact ventricular septum (PA/IVS; 14%), and miscellaneous (2%). Discharge mortality stratified by primary diagnoses was PA/IVS (15.6%), functionally univentricular hearts (7.2%), and diagnoses potentially amenable to biventricular repair (5.1%). Need for preoperative ventilatory support, diagnosis of PA/IVS or functionally univentricular hearts, and any weight less than 3 kg, were risk factors for death. Preoperative acidosis or shock (resolved or persistent) and diagnosis of PA/IVS or functionally univentricular hearts were predictors of composite morbidity. Nearly 33% of the deaths occurred within 24 hours postoperatively, and 75% within the first 30 days. Conclusions The mortality rate after the neonatal modified Blalock-Taussig shunt remains high, particularly for infants weighing less than 3 kg and those with the diagnosis of PA/IVS.
Using combined data from the Relativistic Heavy Ion and Large Hadron Colliders, we constrain the shear and bulk viscosities of quark-gluon plasma (QGP) at temperatures of ∼ 150 – 350 MeV . We use ...Bayesian inference to translate experimental and theoretical uncertainties into probabilistic constraints for the viscosities. With Bayesian model averaging we propagate an estimate of the model uncertainty generated by the transition from hydrodynamics to hadron transport in the plasma's final evolution stage, providing the most reliable phenomenological constraints to date on the QGP viscosities.
The Society of Thoracic Surgeons Adult Cardiac Surgery Database is one of the most mature, comprehensive, and respected clinical data registries in health care. Through nearly three decades of growth ...and refinement, it is widely recognized for accurately benchmarking risk-adjusted outcomes in cardiac surgery and serves as the foundation for all quality measurement and improvement activities of The Society of Thoracic Surgeons. This is the fourth in a series of annual reports that provides updated national outcomes, volume trends, and database-related developments in quality measurement and performance improvement.
BACKGROUND:Optimal strategies to improve national congenital heart surgery outcomes and reduce variability across hospitals remain unclear. Many policy and quality improvement efforts have focused ...primarily on higher-risk patients and mortality alone. Improving our understanding of both morbidity and mortality and current variation across the spectrum of complexity would better inform future efforts.
METHODS:Hospitals participating in the Society of Thoracic Surgeons Congenital Heart Surgery Database (2014–2017) were included. Case mix–adjusted operative mortality, major complications, and postoperative length of stay were evaluated using Bayesian models. Hospital variation was quantified by the interdecile ratio (IDR, upper versus lower 10%) and 95% credible intervals (CrIs). Stratified analyses were performed by risk group (Society of Thoracic Surgeons–European Association for Cardiothoracic Surgery STAT category) and simulations evaluated the potential impact of reductions in variation.
RESULTS:A total of 102 hospitals (n=84 407) were included, representing ≈85% of US congenital heart programs. STAT category 1 to 3 (lower risk) operations comprised 74% of cases. All outcomes varied significantly across hospitalsadjusted mortality by 3-fold (upper versus lower decile 5.0% versus 1.6%, IDR 3.1 95% CrI 2.5–3.7), mean length of stay by 1.8-fold (19.2 versus 10.5 days, IDR 1.8 95% CrI 1.8–1.9), and major complications by >3-fold (23.5% versus 7.0%, IDR 3.4 95% CrI 3.0–3.8). The degree of variation was similar or greater for low- versus high-risk cases across outcomes, eg, ≈3-fold mortality variation across hospitals for STAT 1 to 3 (IDR 3.0 95% CrI 2.1–4.2) and STAT 4 or 5 (IDR 3.1 95% CrI 2.4–3.9) cases. High-volume hospitals had less variability across outcomes and risk categories. Simulations suggested potential reductions in deaths (n=282), major complications (n=1539), and length of stay (101 183 days) over the 4-year study period if all hospitals were to perform at the current median or better, with 37% to 60% of the improvement related to the STAT 1 to 3 (lower risk) group across outcomes.
CONCLUSIONS:We demonstrate significant hospital variation in morbidity and mortality after congenital heart surgery. Contrary to traditional thinking, a substantial portion of potential improvements that could be realized on a national scale were related to variability among lower-risk cases. These findings suggest modifications to our current approaches to optimize care and outcomes in this population are needed.
Data from The Society of Thoracic Surgeons Adult Cardiac Surgery Database were analyzed to identify trends in patient characteristics and outcomes of mitral valve operations in North America.
All ...patients with isolated primary mitral valve operations with or without tricuspid valve repair, surgical atrial fibrillation ablation, or atrial septal defect closure performed July 2011 to September 2016 were identified. A subgroup analysis assessed patients with degenerative leaflet prolapse (DLP).
Isolated primary mitral valve operations were performed on 87,214 patients at 1,125 centers, increasing by 24% between 2011 (n = 14,442) and 2016 (n = 17,907). The most common etiology was DLP (60.7%); 4.3% had functional mitral regurgitation. Preoperatively, 47.3% of patients had an ejection fraction less than 60% and 34.2% had atrial fibrillation. Overall mitral valve repair rate was 65.6%, declining from 67.1% (2011) to 63.2% (2016; p < 0.0001). Repair rates were related to etiology (DLP, 82.5%; rheumatic, 17.5%). Of the 29,970 mitral valve replacements, 16.2% were preceded by an attempted repair. Repair techniques included prosthetic annuloplasty (94.3%), leaflet resection (46.5%), and artificial cord implantation (22.7%). Bioprosthetic valves were implanted with increasing frequency (2011, 65.4%; 2016, 75.8%; p < 0.0001). Less-invasive operations were performed in 23.0% and concomitant tricuspid valve repair in 15.7%. Unadjusted operative mortality was 3.7% (replacements) and 1.1% (repairs).
Patients undergoing primary isolated mitral valve operations commonly have ventricular dysfunction, atrial fibrillation, and heart failure. Although contemporary outcomes are excellent, earlier guideline-directed referral and increased frequency and quality of repair may further improve results of mitral valve operations.
The Society of Thoracic Surgeons (STS) uses statistical models to create risk-adjusted performance metrics for Adult Cardiac Surgery Database (ACSD) participants. Because of temporal changes in ...patient characteristics and outcomes, evolution of surgical practice, and additional risk factors available in recent ACSD versions, completely new risk models have been developed.
Using July 2011 to June 2014 ACSD data, risk models were developed for operative mortality, stroke, renal failure, prolonged ventilation, mediastinitis/deep sternal wound infection, reoperation, major morbidity or mortality composite, prolonged postoperative length of stay, and short postoperative length of stay among patients who underwent isolated coronary artery bypass grafting surgery (n = 439,092), aortic or mitral valve surgery (n = 150,150), or combined valve plus coronary artery bypass grafting surgery (n = 81,588). Separate models were developed for each procedure and endpoint except mediastinitis/deep sternal wound infection, which was analyzed in a combined model because of its infrequency. A surgeon panel selected predictors by assessing model performance and clinical face validity of full and progressively more parsimonious models. The ACSD data (July 2014 to December 2016) were used to assess model calibration and to compare discrimination with previous STS risk models.
Calibration in the validation sample was excellent for all models except mediastinitis/deep sternal wound infection, which slightly underestimated risk and will be recalibrated in feedback reports. The c-indices of new models exceeded those of the last published STS models for all populations and endpoints except stroke in valve patients.
New STS ACSD risk models have generally excellent calibration and discrimination and are well suited for risk adjustment of STS performance metrics.
The Interagency Registry for Mechanically Assisted Circulatory Support (Intermacs), a joint effort among the National Heart, Lung, and Blood Institute, the Food and Drug Administration, the Centers ...for Medicare and Medicaid Services, and others, was established in 2005 at the University of Alabama at Birmingham. The registry examined clinical outcomes and quality-of-life metrics of patients who received an Food and Drug Administration-approved durable mechanical circulatory support (MCS) device to treat advanced heart failure. On January 1, 2018, the Intermacs Database became part of The Society of Thoracic Surgeons National Database, providing additional resources for quality assessment and improvement and scientific advancement.
The Intermacs Database Annual Report summarizes outcomes in patients (≥19 years of age) who underwent durable MCS implant between June 23, 2006, and December 31, 2017. Outcomes are presented for patients who underwent isolated continuous flow left ventricular assist device (CF LVAD) support, CF LVAD support with concomitant right ventricular assist device (RVAD) implant, or total artificial heart implant. Analyses of patients with CF LVADs are stratified by axial flow and centrifugal flow configurations. Because of the association of era with outcomes, the survival analyses are restricted to isolated CF LVADs implanted in the 2012 to 2016 era.
There were 25,145 adult patients with MCS reported to Intermacs, of whom 18,539 (74%) received CF LVADs, 667 (2.6%) had an RVAD with CF LVAD, 339 received a total artificial heart (1.3%), and 20 (0.07%) received an isolated RVAD. Of the CF LVADs, mean age was 57 ± 1 years, 26% were listed for transplantation, and 51% were in cardiogenic shock (profile 1 to 2) preoperatively. CF LVADs included 14,527 axial flow (78%) and 4,012 centrifugal flow (22%) devices. Intermacs patient phenotype has evolved over time to include more patients with profile 3 (26% in 2006 to 2011 versus 35% in 2012 to 2016) and fewer patients with profile 2 (40% versus 35%), patients with better markers of preoperative renal and hepatic function, and more patients who received implants for destination therapy (29% versus 48%) indication. In 2017, centrifugal flow implants (51%) approximated that of axial flow devices (49%). Mean CF LVAD support duration was 20 months (31,563 patient-years). One-year survival for isolated CF LVADs was 83% and 5-year survival was 46%. One-year survivals for centrifugal versus axial flow devices were 85% and 84%, respectively. Patients who required concomitant RVAD support had 1- and 5-year survivals of 58% and 28%, respectively. Freedom from all-cause readmission was 70% at 1 month and 20% at 1 year. At 1 year, stroke occurred in 20% of patients on centrifugal flow and 13% of patients on axial flow support (p < 0.001), gastrointestinal bleeding affected 20% of patients with centrifugal flow devices and 25% of patients with axial flow devices (p < 0.001), and pump-related infection occurred in 28% of patients with centrifugal flow devices versus 25% of patients with axial flow devices (p = 0.01). Neurologic dysfunction (19% of deaths) and multisystem organ dysfunction (15%) were the most common causes of death.
With the evolution of MCS, patient phenotype and outcomes are also changing over time. CF LVAD support is increasingly being used in the less ill patient phenotype and more patients are supported for destination therapy. Mean survival is now approaching 5 years, but adverse events, especially neurologic events, continue to have a detrimental impact on the success of CF LVAD support.
PDF
