Faculty Bibliography

Three cases of LVAD outflow graft compression by material accumulated within a polytetrafluoroethylene external protective graft are presented.

BACKGROUND:Temporary mechanical circulatory support (MCS) devices provide hemodynamic assistance for shock refractory to pharmacological treatment. Most registries have focused on single devices or specific etiologies of shock, limiting data regarding overall practice patterns with temporary MCS in cardiac intensive care units. METHODS:The CCCTN (Critical Care Cardiology Trials Network) is a multicenter network of tertiary CICUs in North America. Between September 2017 and September 2018, each center (n=16) contributed a 2-month snapshot of consecutive medical CICU admissions. RESULTS:Of the 270 admissions using temporary MCS, 33% had acute myocardial infarction-related cardiogenic shock (CS), 31% had CS not related to acute myocardial infarction, 11% had mixed shock, and 22% had an indication other than shock. Among all 585 admissions with CS or mixed shock, 34% used temporary MCS during the CICU stay with substantial variation between centers (range: 17%-50%). The most common temporary MCS devices were intraaortic balloon pumps (72%), Impella (17%), and veno-arterial extracorporeal membrane oxygenation (11%), although intraaortic balloon pump use also varied between centers (range: 40%-100%). Patients managed with intraaortic balloon pump versus other forms of MCS (advanced MCS) had lower Sequential Organ Failure Assessment scores and less severe metabolic derangements. Illness severity was similar at high- versus low-MCS utilizing centers and at centers with more advanced MCS use. CONCLUSIONS:There is wide variation in the use of temporary MCS among patients with shock in tertiary CICUs. While hospital-level variation in temporary MCS device selection is not explained by differences in illness severity, patient-level variation appears to be related, at least in part, to illness severity.

Importance/UNASSIGNED:Single-center and claims-based studies have described substantial changes in the landscape of care in the cardiac intensive care unit (CICU). Professional societies have recommended research to guide evidence-based CICU redesigns. Objective/UNASSIGNED:To characterize patients admitted to contemporary, advanced CICUs. Design, Setting, and Participants/UNASSIGNED:This study established the Critical Care Cardiology Trials Network (CCCTN), an investigator-initiated multicenter network of 16 advanced, tertiary CICUs in the United States and Canada. For 2 months in each CICU, data for consecutive admissions were submitted to the central data coordinating center (TIMI Study Group). The data were collected and analyzed between September 2017 and 2018. Main Outcomes and Measures/UNASSIGNED:Demographics, diagnoses, management, and outcomes. Results/UNASSIGNED:Of 3049 participants, 1132 (37.1%) were women, 797 (31.4%) were individuals of color, and the median age was 65 years (25th and 75th percentiles, 55-75 years). Between September 2017 and September 2018, 3310 admissions were included, among which 2557 (77.3%) were for primary cardiac problems, 337 (10.2%) for postprocedural care, 253 (7.7%) for mixed general and cardiac problems, and 163 (4.9%) for overflow from general medical ICUs. When restricted to the initial 2 months of medical CICU admissions for each site, the primary analysis population included 3049 admissions with a high burden of noncardiovascular comorbidities. The top 2 CICU admission diagnoses were acute coronary syndrome (969 [31.8%]) and heart failure (567 [18.6%]); however, the proportion of acute coronary syndrome was highly variable across centers (15%-57%). The primary indications for CICU care included respiratory insufficiency (814 [26.7%]), shock (643 [21.1%]), unstable arrhythmia (521 [17.1%]), and cardiac arrest (265 [8.7%]). Advanced CICU therapies or monitoring were required for 1776 patients (58.2%), including intravenous vasoactive medications (1105 [36.2%]), invasive hemodynamic monitoring (938 [30.8%]), and mechanical ventilation (652 [21.4%]). The overall CICU mortality rate was 8.3% (95% CI, 7.3%-9.3%). The CICU indications that were associated with the highest mortality rates were cardiac arrest (101 [38.1%]), cardiogenic shock (140 [30.6%]), and the need for renal replacement therapy (51 [34.5%]). Notably, patients admitted solely for postprocedural observation or frequent monitoring had a mortality rate of 0.2% to 0.4%. Conclusions and Relevance/UNASSIGNED:In a contemporary network of tertiary care CICUs, respiratory failure and shock predominated indications for admission and carried a poor prognosis. While patterns of practice varied considerably between centers, a substantial, low-risk population was identified. Multicenter collaborative networks, such as the CCCTN, could be used to help redesign cardiac critical care and to test new therapeutic strategies.

Background Clinical investigations of shock in cardiac intensive care units (CICUs) have primarily focused on acute myocardial infarction (AMI) complicated by cardiogenic shock (AMICS). Few studies have evaluated the full spectrum of shock in contemporary CICUs. Methods and Results The Critical Care Cardiology Trials Network is a multicenter network of advanced CICUs in North America. Anytime between September 2017 and September 2018, each center (n=16) contributed a 2-month snap-shot of all consecutive medical admissions to the CICU. Data were submitted to the central coordinating center (TIMI Study Group, Boston, MA). Shock was defined as sustained systolic blood pressure <90 mm Hg with end-organ dysfunction ascribed to the hypotension. Shock type was classified by site investigators as cardiogenic, distributive, hypovolemic, or mixed. Among 3049 CICU admissions, 677 (22%) met clinical criteria for shock. Shock type was varied, with 66% assessed as cardiogenic shock (CS), 7% as distributive, 3% as hypovolemic, 20% as mixed, and 4% as unknown. Among patients with CS (n=450), 30% had AMICS, 18% had ischemic cardiomyopathy without AMI, 28% had nonischemic cardiomyopathy, and 17% had a cardiac cause other than primary myocardial dysfunction. Patients with mixed shock had cardiovascular comorbidities similar to patients with CS. The median CICU stay was 4.0 days (interquartile range [IQR], 2.5-8.1 days) for AMICS, 4.3 days (IQR, 2.1-8.5 days) for CS not related to AMI, and 5.8 days (IQR, 2.9-10.0 days) for mixed shock versus 1.9 days (IQR, 1.0-3.6) for patients without shock ( P<0.01 for each). Median Sequential Organ Failure Assessment scores were higher in patients with mixed shock (10; IQR, 6-13) versus AMICS (8; IQR, 5-11) or CS without AMI (7; IQR, 5-11; each P<0.01). In-hospital mortality rates were 36% (95% CI, 28%-45%), 31% (95% CI, 26%-36%), and 39% (95% CI, 31%-48%) in AMICS, CS without AMI, and mixed shock, respectively. Conclusions The epidemiology of shock in contemporary advanced CICUs is varied, and AMICS now represents less than one-third of all CS. Despite advanced therapies, mortality in CS and mixed shock remains high. Investigation of management strategies and new therapies to treat shock in the CICU should take this epidemiology into account.

BACKGROUND:There is substantial variability among hospitals in critical care unit (CCU) utilization for patients admitted with non-ST-Segment Elevation Acute Coronary Syndromes (NSTE ACS). We estimated the potential cost saving if all hospitals adopted low CCU utilization practices for patients with NSTE ACS. METHODS:National hospital claims data were used to identify all patients with a primary diagnosis of NSTE ACS initially admitted to an acute care hospital between 2007 and 2013. Hospital CCU utilization was classified as low (<30%), medium (30-70%), or high (>70%). RESULTS:Among the 270,564 NSTE ACS hospitalizations (71.6% non-ST-segment elevation myocardial infarction; 28.4% unstable angina) admitted to 261 hospitals, 41.9% (inter-hospital range 0.3%-95.1%) were admitted to a CCU. The proportion of patients admitted to a CCU in low, medium and high utilization hospitals was 16.3%, 49.5%, and high 81.1%, respectively. No differences in adjusted inpatient mortality were observed by hospital CCU utilization. The overall inpatient costs of caring for NSTE ACS were $1.1 billion. CCU care accounted for 45.2% of all hospitalization costs including 22.6%, 49.9%, and 69.0% (P < .001) of costs in low, medium and high utilization centers. The national potential direct cost savings of medium and high CCU utilization centers adopting low NSTE ACS CCU utilization practices was $113.4 million over the study period. CONCLUSIONS:In a population-based contemporary cohort, CCU utilization for patients with NSTE ACS varied widely and in-hospital mortality was similar between low, medium and high utilization centers. CCU care accounted for 45% of hospitalization costs; thus, implementing policies and admission practices to align hospital resources with patient care needs have the potential to reduce overall health care costs.

BACKGROUND:Hemolysis, assessed by elevated serum lactate dehydrogenase (LDH), is strongly associated with HeartMate II pump thrombosis (PT). However, it is unknown whether early intervention for elevated LDH circumvents the risk of serious PT requiring pump exchange. We sought to evaluate the relationship between elevated LDH and clinical outcomes, the effectiveness of early medical intervention, and risk factors for elevated LDH. METHODS:We studied 268 patients in the prospective, multicenter PREVENT study who had 2 or more LDH measurements at ≥30 days post-implant. Elevated LDH was defined as LDH ≥2.5× upper limit of normal (ULN) for 2 consecutive measurements. RESULTS:Fourteen percent of patients had elevated LDH. Stroke-free survival at 6 months was lower in patients with elevated LDH vs patients with normal LDH (83 ± 6% vs 93 ± 2%, p = 0.035). Elevated LDH resolved without intervention in 19% of patients, with intensified medical therapy in 43% and required surgical intervention in 38%. For patients receiving only medical therapy, survival was 94 ± 6% at 6 months post-treatment. In this subgroup, resolution of symptoms with intensified medical therapy was sustained in 15 of 16 patients, with PT occurring in 1 patient at 171 days after initial treatment for elevated LDH (202 days post-implant). Early medical intervention at moderately elevated LDH (2.5× to 3.2× ULN), as compared with higher levels (>3.2× ULN), led to more sustained resolution of symptoms without subsequent PT or need for surgical intervention (91% vs 26% at 6 months post-treatment, p = 0.002). CONCLUSIONS:Early medical intervention can successfully resolve moderate LDH elevations (2.5× to 3.2× ULN) with a low incidence of death or PT at 6 months post-treatment.

BACKGROUND:Quality indicators (QIs) are increasingly used in cardiovascular care as measures of performance but there is currently no consensus on indicators for the cardiovascular intensive care unit (CICU). METHODS:We searched Medline, CINAHL, EMBASE, and COCHRANE databases from inception until October 2016 and websites for organizations involved in quality measurement for QIs relevant to cardiovascular disease in an intensive or critical care setting. We surveyed 14 expert cardiac intensivist-administrators (7 European; 7 North American) on the importance and relevance of each indicator as a measure of CICU care quality using a scale of 1 (=lowest) to 10 (=highest). Indicators with a mean score ≥8/10 for both importance and relevance were included in the final set. RESULTS:Overall, 108 QIs (70 process, 18 structural, 18 outcome, 1 patient engagement, and 1 covering multiple domains) were identified in 30 articles representing 23 agencies, organizations, and societies. Disease-specific QIs included myocardial infarction (n = 37), heart failure (n = 31), atrial fibrillation (n = 11), and cardiac rehabilitation (n = 1); general QIs represented about one-quarter (n = 28) of all measures. Fifteen QIs were selected for the final QI set: 7 process, 2 structural, and 6 outcome measures, including 6 general and 9 disease-specific measures. Outcome measures chosen to evaluate general CICU performance included overall CICU mortality, length of stay, and readmission rate. CONCLUSIONS:Numerous QIs relevant to the CICU have been recommended by a variety of organizations. The indicators chosen by the cardiac intensivist-administrators could serve as a basis for future efforts to develop a standardized set of quality measures for the CICU.

Left ventricular assist device (LVAD) therapy has emerged as an increasingly vital facet of the treatment algorithm for advanced heart failure. Growing experience with LVAD support has led to substantial improvements in outcomes, with 1-year survival rates approaching that of cardiac transplantation. These therapeutic refinements have engendered growing interests in the potential for expanding the clinical indications for LVAD therapy to patients with less advanced heart failure. The primary obstacles to this evolution of care center largely on the prevention and/or management of the adverse events associated with LVAD therapy along with patient preference. Many programs also face the mounting difficulty of balancing quality outcomes with the increased volume of implants. During the recently assembled Users Meeting organized by St. Jude Medical, heart failure clinicians from nearly 50 LVAD implanting centers discussed these and other challenges and controversies impacting the field. The present review summarizes the key insights gleaned from this meeting.

BACKGROUND:Long-term survivors after implantation of left ventricular assist devices (LVADs) are increasing in prevalence. We describe the characteristics and outcomes in patients surviving longer than 4 years on LVAD support. METHODS:We performed a multicenter, retrospective analysis of patients surviving at least 4 years on continuous-flow LVAD (CF-LVAD) support with a HeartMate II at centers participating in the Evolving Mechanical support Research Group. RESULTS:Between 2005 and 2010, 156 long-term survivors were identified with a mean survival of 7.1 years (95% confidence interval: 6.7 to 7.5 years). The mean age was 58.2 ± 15.2 years and 30.1% were women. Readmission rate was low at 1.1 events per patient per year with the most common reasons leading to readmission being infection (0.10 readmissions per patient per year) and gastrointestinal bleeding (0.07 readmissions per patient per year). Two years after implantation, 97% of patients were either New York Heart Association functional class I or II, with 92% at 4 years. CONCLUSIONS:Patients surviving 4 years on CF-LVAD support can anticipate ongoing long-term survival with sustained improvements in functionality and low rates of rehospitalization.