Faculty Bibliography

OBJECTIVES:The goal of this study was to assess the utility of transvenous lead extraction for cardiovascular implantable electronic device (CIED) infection in patients with a left ventricular assist device (LVAD). BACKGROUND:The use of transvenous lead extraction for the management CIED infection in patients with a durable LVAD has not been well described. METHODS:Clinical and outcomes data were collected retrospectively among patients who underwent lead extraction for CIED infection after LVAD implantation at Duke University Hospital. RESULTS:Overall, 27 patients (n = 6 HVAD; n = 15 HeartMate II; n = 6 Heartmate III) underwent lead extraction for infection. Median (interquartile range) time from LVAD implantation to infection was 6.1 (2.5 to 14.9) months. Indications included endocarditis (n = 16), bacteremia (n = 9), and pocket infection (n = 2). Common pathogens were Staphylococcus aureus (n = 10), coagulase-negative staphylococci (n = 7), and Enterococcus faecalis (n = 3). Sixty-eight leads were removed, with a median lead implant time of 5.7 (3.6 to 9.2) years. Laser sheaths were used in all procedures, with a median laser time of 35.0 s (17.5 to 85.5s). Mechanical cutting tools were required in 11 (40.7%) and femoral snaring in 4 (14.8%). Complete procedural success was achieved in 25 (93.6%) patients and clinical success in 27 (100%). No procedural failures or major adverse events occurred. Twenty-one patients (77.8%) were alive without persistent endovascular infection 1 year after lead extraction. Most were treated with oral suppressive antibiotics after extraction (n = 23 [82.5%]). Persistent infection after extraction occurred in 4 patients and was associated with 50% 1-year mortality. CONCLUSIONS:Transvenous lead extraction for LVAD-associated CIED infection can be performed safely with low rates of persistent infection and 1-year mortality.

BACKGROUND:The prevalence of renal disease in cardiac intensive care units (CICUs) is increasing, but little is known about the utilization, concurrent therapies, and outcomes of patients requiring acute renal replacement therapy (RRT) in this specialized environment. METHODS:In the Critical Care Cardiology Trials Network, 16 centers submitted data on CICU admissions including acute RRT (defined as continuous renal replacement therapy and/or acute intermittent dialysis). RESULTS:Among 2,985 admissions, 178 (6.0%; interhospital range 1.0%-16.0%) received acute RRT. Patients receiving RRT, versus not, were more commonly admitted for cardiogenic shock (15.7% vs 4.2%, P < .01), cardiac arrest (9.6% vs 3.7%, P < .01), and acute general medical diagnoses (10.7% vs 5.8%, P < .01), whereas acute coronary syndromes (16.9% vs 32.1%, P < .01) were less frequent. Variables independently associated with acute RRT included diabetes, heart failure, liver disease, severe valvular disease, shock, cardiac arrest, hypertension, and younger age. In patients receiving acute RRT, versus not, advanced therapies including mechanical ventilation (55.6% vs 18.0%), vasoactive support (73.0% vs 35.2%), invasive hemodynamic monitoring (59.6% vs 29.2%), and mechanical circulatory support (27.5% vs 8.4%) were more common. Acute RRT was associated with higher in-hospital mortality (42.1% vs 9.3%, adjusted odds ratio 3.74, 95% CI, 2.52-5.53) and longer median length of stay (10.0 vs 5.3 days, P < .01). In conclusion, acute RRT in contemporary CICUs was associated with the provision of other advanced therapies and lower survival. CONCLUSIONS:These data underscore the risks associated with the provision of renal support in patients with primary cardiovascular problems and the need to develop standardized indications and potential futility measures in this specialized population.

The use of veno-arterial extracorporeal membrane oxygenation (VA ECMO) has increased substantially over the past few decades. Today's clinicians now have a powerful means with which to salvage a growing population of patients at risk for cardiopulmonary collapse. At the same time, patients supported with VA ECMO have become increasingly more complex. The successful use of VA ECMO depends not only on selecting the appropriate patients, but also on effectively navigating a potential torrent of device- and patient-related complications until ECMO is no longer needed. A multitude of monitoring tools are now available to help the treatment team determine the adequacy of care, to detect problems, and to anticipate recovery. Monitoring with devices such as the Swan-Ganz catheter, transthoracic and transesophageal echocardiography, chest radiography, and near-infrared spectroscopy can provide useful information to complement routine clinical care. Leveraging data derived from the ECMO circuit itself also can be instrumental in both evaluating the sufficiency of support and troubleshooting complications. Each of these tools, however, has its own unique sets of limitations and liabilities. A thorough understanding of these risks and benefits is critical to the contemporary care of the individual managed with VA ECMO. In addition, more research is needed to establish optimal evidence-based care pathways and best-practice principles for using these devices to improve patient outcomes.

Longevity is increasing, and more adults are living to the stage of life when age-related biological factors determine a higher likelihood of cardiovascular disease in a distinctive context of concurrent geriatric conditions. Older adults with cardiovascular disease are frequently admitted to cardiac intensive care units (CICUs), where care is commensurate with high age-related cardiovascular disease risks but where the associated geriatric conditions (including multimorbidity, polypharmacy, cognitive decline and delirium, and frailty) may be inadvertently exacerbated and destabilized. The CICU environment of procedures, new medications, sensory overload, sleep deprivation, prolonged bed rest, malnourishment, and sleep is usually inherently disruptive to older patients regardless of the excellence of cardiovascular disease care. Given these fundamental and broad challenges of patient aging, CICU management priorities and associated decision-making are particularly complex and in need of enhancements. In this American Heart Association statement, we examine age-related risks and describe some of the distinctive dynamics pertinent to older adults and emerging opportunities to enhance CICU care. Relevant assessment tools are discussed, as well as the need for additional clinical research to best advance CICU care for the already dominating and still expanding population of older adults.

Extracorporeal membrane oxygenation has evolved, from a therapy that was selectively applied in the pediatric population in tertiary centers, to more widespread use in diverse forms of cardiopulmonary failure in all ages. We provide a practical review for cardiovascular clinicians on the application of veno-arterial extracorporeal membrane oxygenation in adult patients with cardiogenic shock, including epidemiology of cardiogenic shock, indications, contraindications, and the extracorporeal membrane oxygenation circuit. We also summarize cannulation techniques, practical management and troubleshooting, prognosis, and weaning and exit strategies, with attention to end of life and ethical considerations.

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.

INTRODUCTION:Patients with a continuous-flow left ventricular assist device (CF-LVAD) require anticoagulation with a vitamin K antagonist to prevent thromboembolic events. Fluctuations in the international normalized ratio are associated with both increased thrombotic and bleeding episodes. To date, risk factors for low time in therapeutic range (TTR) among ambulatory patients with a CF-LVAD have not been explored. METHODS:A retrospective single-center analysis of 121 patients implanted with a CF-LVAD was performed. International normalized ratios were systematically recorded from the initial postdischarge outpatient visit to 12 months of time on the device. Risk factors for low TTR were evaluated using a multivariable linear regression analysis. Each of the 21 independent variables was entered into a stepwise regression designed to minimize the Akaike information criteria. RESULTS:In the multivariable analysis, the model output revealed that every 1-year increase in age was associated with a 0.4% increase in TTR (p=0.008), and every 1 mile further from clinic was associated with a 0.08% increase in TTR (p=0.03). Female sex was associated with a 10.1% decrease in TTR (p=0.04), type 2 diabetes was associated with an 11.5% decrease in TTR (p=0.006), and prior warfarin use was associated with an 8.3% decrease in TTR (p=0.03). CONCLUSION:In CF-LVAD recipients receiving warfarin, increasing age and distance from clinic are independent predictors of higher TTR. Female sex, type 2 diabetes, and prior warfarin use are independent predictors of lower TTR.

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.

UNLABELLED:Prior studies have demonstrated that the cardiac intensive care unit (CICU) patient population has evolved over time. We sought to describe the temporal changes in comorbidities, illness severity, diagnoses, procedures and adjusted mortality within our CICU practice in recent years. METHODS:We retrospectively reviewed unique CICU admissions at the Mayo Clinic from January 2007 to April 2018. Comorbidities, severity of illness scores, discharge diagnosis codes and CICU procedures and therapies were recorded, and temporal trends were assessed using linear regression and Cochran-Armitage trend tests. Trends in adjusted hospital mortality over time were assessed using multivariable logistic regression. RESULTS:We included 12,418 patients with a mean age of 67.6 years (including 37.7% females). Temporal trends in the prevalence of several comorbidities and discharge diagnoses were observed, reflecting an increase in the prevalence of non-coronary cardiovascular diseases, critical care diagnoses, and organ failure (all P ≪ .05). The use of several CICU therapies and procedures increased over time, including mechanical ventilation, invasive lines and vasoactive drugs (all P ≪ .05). A temporal decrease in adjusted hospital mortality was observed among the subgroup of patients with (adjusted OR per year 0.97, 95% CI 0.94-0.99, P = .023) and without (adjusted OR per year 0.91, 95% CI 0.85-0.96, P = .002) a critical care discharge diagnosis. CONCLUSIONS:We observed an increasing prevalence of critical care and organ failure diagnoses as well as increased utilization of critical care therapies in this CICU cohort, associated with a decrease in risk-adjusted hospital mortality over time.