Faculty Bibliography

Background Arrhythmogenic cardiomyopathy (ACM) can mimic inflammatory processes. We present a complex patient with scleroderma (Sc)-dermatomyositis overlap syndrome (Sc-DM) and cardiac disease. Case A 57-year-old woman with family history of Sc presented with progressive weakness, dyspnea, edema, and Raynaud's (1A). Troponin was 1.6 ng/mL and CRP was 13.2 mg/L. EKGs revealed sinus rhythm with RBBB and AV sequential pacing with multifocal PVCs (1B-C). CT chest showed bibasilar fibrosis (1D). Echocardiography revealed biventricular dysfunction. Cardiac catheterization showed non-obstructive coronaries and a cardiac index of 1.8 L/min/m2. Cardiac MRI had diffuse biventricular subendocardial late gadolinium enhancement (1E). Electromyography revealed proximal myopathy. Rheumatologic workup was consistent with seronegative Sc-DM. Decision-making She was treated with steroids, mycophenolate, IV immunoglobulins, diuretics, and inotropes. Her course was complicated by recurrent VT cardiac arrests, prompting escalation to VA-ECMO. She underwent cardiac transplant on day 9 of ECMO. Pathology revealed biventricular fibrofatty replacement consistent with ACM (1F-G), patchy fibrosis of the pericardium, and mitral valve with thickened and fused chordae suggestive of inflammatory changes from Sc (1H-I). Conclusion This case highlights an atypical presentation of ACM in a patient with Sc-DM and the multidisciplinary approach necessary for proper diagnosis and management. [Figure presented]
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Background Positive end-expiratory pressure (PEEP) may have differential hemodynamic effects according to right ventricular (RV), left ventricular (LV) function and filling pressures. We assessed the association between PEEP and outcomes in patients (pts) admitted to the cardiac intensive care unit (CICU) undergoing mechanical ventilation (MV). Methods Patients undergoing MV in the first 48 hours of CICU admission at Beth Israel Deaconess Medical Center (MIMIC III database) were included. Pts were stratified into preload dependent (hypovolemia, RV dysfunction, tamponade, hypertrophic obstructive cardiomyopathy) and high afterload (LV dysfunction). Pts with a pulmonary artery catheter (PAC) were classified by their pulmonary artery diastolic pressure (PADP) as high (>20mmHg) and normal (<20mmHg). Mortality, lactate clearance and inotropic vasopressor score were compared in pts with PEEP levels above and below the median. Multivariable regression analysis was performed adjusting for age, sex, OASIS score, PaO2, pH, lactate and cardiac arrest on admission. Results We included 321 CICU pts (age 68, IQR 57-78) who had a median PEEP levels of 5.38 (IQR 5.00-6.78) cmH2O in the preload dependent group and 5.00 (IQR 5.00-8.00) cmH2O in the afterload dependent group. Unadjusted hospital mortality was higher in pts receiving PEEP above the median in the preload dependent group (66.7% vs. 36.4%, p=0.04, adjusted OR 1.74 95%CI 0.85-3.57, p=0.12), but not in the afterload dependent group (31.1% vs. 26% p=0.51, adjusted OR 1.002 95%CI 0.81-1.24, p=0.98). In patients with PAC (n=80), multivariate analysis demonstrated no differences in mortality by PEEP in low PADP (OR 0.93, 95%CI 0.38-2.75, p=0.87) or high PADP (OR 1.17, 95%CI 0.72-1.91p=0.51). There were no differences in lactate clearance or inotropic/vasopressor score by PEEP in preload/afterload dependent status and with normal/high PADP. Conclusion In CICU pts undergoing MV, the use of low-moderate levels of PEEP was not associated with differences in outcomes. Further research is warranted to better characterize the impact of PEEP, particularly at higher levels, on hemodynamics and clinical outcomes.
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Cardiogenic shock (CS) is often complicated by respiratory failure, and more than 80% of patients with CS require respiratory support. Elevated filling pressures from left-ventricular (LV) dysfunction lead to alveolar pulmonary edema, which impairs both oxygenation and ventilation. The implementation of positive pressure ventilation (PPV) improves gas exchange and can improve cardiovascular hemodynamics by reducing preload and afterload of the LV, reducing mitral regurgitation and decreasing myocardial oxygen demand, all of which can help augment cardiac output and improve tissue perfusion. In right ventricular (RV) failure, however, PPV can potentially decrease preload and increase afterload, which can potentially lead to hemodynamic deterioration. Thus, a working understanding of cardiopulmonary interactions during PPV in LV and RV dominant CS states is required to safely treat this complex and high-acuity group of patients with respiratory failure. Herein, we provide a review of the published literature with a comprehensive discussion of the available evidence on the use of PPV in CS. Furthermore, we provide a practical framework for the selection of ventilator settings in patients with and without mechanical circulatory support, induction, and sedation methods, and an algorithm for liberation from PPV in patients with CS.

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.

Despite increasing medical complexity in patients with heart failure (HF), there are limited data on incidence and outcomes for patients with HF needing respiratory support. This study sought to examine contemporary trends of respiratory support strategies among patients with HF. Using the National Inpatient Sample, we identified adults aged greater than 18 years hospitalized with a primary diagnosis of HF. We assessed for trends in the use of invasive mechanical ventilation (IMV) and noninvasive ventilation (NIV), length of stay, hospital costs, and in-hospital mortality. From 2002 to 2014, we identified 9,508,768 HF hospitalizations, which included 202,340 (2.13%) and 257,549 (2.71%) patients that required IMV and NIV, respectively. Over the study period, the proportion of HF patients requiring IMV significantly decreased (3.25% in 2002 to 1.56% in 2014) whereas the use of NIV significantly increased from 0.95% to 7.25% (p_trend <0.001 for both). In-hospital mortality significantly increased for IMV (31.5% in 2002 to 38.6% in 2014) recipients and decreased for patients requiring NIV (9.0% to 5.6%, p_trend <0.0001 for both). The average length of stay was nearly 7 days longer in the IMV group (12.2 days) and 2 days longer in the NIV group (6.8 days; p <0.001 for both). Hospital charges have nearly tripled for patients requiring IMV ($99,358 in 2014, p_trend <0.001) and doubled for those requiring NIV ($37,539 in 2014, p_trend <0.001). In conclusion, respiratory support strategies for patients with HF have significantly evolved with increasing use of NIV as compared with IMV. However, the in-hospital mortality associated with respiratory failure remains unacceptably high.

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:Sodium nitroprusside is the preferred agent for the treatment of high blood pressure during acute aortic syndrome if blood pressure remains elevated after heart rate control with beta-blockers. The increasing cost of sodium nitroprusside in the USA led us to assess the efficacy and safety of intravenous clevidipine, a calcium channel blocker with quick onset of action, short half-life and significantly lower costs than sodium nitroprusside, in patients presenting with acute aortic syndrome. METHODS:We performed a retrospective chart review of consecutive patients admitted to the Cleveland Clinic Cardiac Intensive Care Unit from 2013-2016 with a diagnosis of acute aortic syndrome. Patients who received intravenous sodium nitroprusside were compared with those receiving intravenous clevidipine. The primary outcome was a significant difference in blood pressure at one, three and six hours. Secondary outcomes included time to achieving blood pressure target and in hospital mortality with rates of hypotension and bradycardia as safety endpoints. RESULTS:A total of 85 patients with suspected acute aortic pathology received clevidipine and 50 received sodium nitroprusside. Clinical and demographic characteristics were similar in both groups, except for a higher incidence of abdominal aortic aneurysm in the clevidipine group and for a trend towards higher use of labetalol in the clevidipine group. There were no significant differences in blood pressure or heart rate at one, three and six hours after starting either infusion. The rates of hypotension, bradycardia and in-hospital mortality did not differ. Time to achieve blood pressure control were also similar between groups. CONCLUSION/CONCLUSIONS:Intravenous clevidipine appears to be a safe and effective alternative to sodium nitroprusside for the management of high blood pressure during acute aortic dissection. In the USA, clevidipine could represent a cost effective therapy providing similar outcomes than sodium nitroprusside.

Contemporary cardiac intensive care units (CICUs) provide care for an aging and increasingly complex patient population. The medical complexity of this population is partly driven by an increased proportion of patients with respiratory failure needing noninvasive or invasive positive pressure ventilation (PPV). PPV often plays an important role in the management of patients with cardiogenic pulmonary edema, cardiogenic shock, or cardiac arrest, and those undergoing mechanical circulatory support. Noninvasive PPV, when appropriately applied to selected patients, may reduce the need for invasive mechanical PPV and improve survival. Invasive PPV can be lifesaving, but has both favorable and unfavorable interactions with left and right ventricular physiology and carries a risk of complications that influence CICU mortality. Effective implementation of PPV requires an understanding of the underlying cardiac and pulmonary pathophysiology. Cardiologists who practice in the CICU should be proficient with the indications, appropriate selection, potential cardiopulmonary interactions, and complications of PPV.