Faculty Bibliography

The COVID-19 pandemic has presented a major unanticipated stress on our workforce, organizational structure, systems of care, and critical resource supply. In order to ensure provider safety, maximize efficiency, and optimize patient outcomes, health systems need to be agile. Critical care cardiologists may be uniquely positioned to treat the numerous respiratory and cardiovascular complications of the SARS-CoV-2 virus and support clinicians without critical care training who may be suddenly asked to care for critically ill patients. This manuscript draws upon the experiences of colleagues from heavily impacted regions of the United States and Europe as well as lessons learned from military mass casualty medicine. We offer pragmatic suggestions on how to implement scalable models for critical care delivery, cultivate educational tools for team training, and embrace technologies such as telemedicine to enable effective collaboration despite social distancing imperatives.

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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BACKGROUND:Little is known about clinical outcomes of patients with acute myocardial infraction (AMI) complicated by cardiogenic shock (CS) requiring mechanical ventilation (MV). The aim of this study was to identify the characteristics, risk factors, and outcomes associated with the provision of MV in this specific high-risk population. METHODS:Patients with CS complicating AMI and multivessel coronary artery disease from the CULPRIT-SHOCK trial were included. We explored 30 days of clinical outcomes in patients not requiring MV, those with MV on admission, and those in whom MV was initiated within the first day after admission. RESULTS:Among 683 randomized patients included in the analysis, 17.4% received no MV, 59.7% were ventilated at admission and 22.8% received MV within or after the first day after admission. Patients requiring MV had a different risk-profile. Factors independently associated with the provision of MV on admission included higher body weight, resuscitation within 24 h before admission, elevated heart rate and evidence of triple vessel disease. CONCLUSIONS:Requiring MV in patients with CS complicating AMI is common and independently associated with mortality after adjusting for covariates. Patients with delayed MV initiation appear to be at higher risk of adverse outcomes. Further research is necessary to identify the optimal timing of MV in this high-risk population.

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.

Chronic obstructive lung diseases and CVD are common conditions with a significant prevalence worldwide and substantial morbidity. There is a growing body of evidence that associates asthma as a potential risk factor for CVD, in particular, CAD, acute myocardial infarction and stroke. These observations appear to be stronger in patients with uncontrolled asthma and in women. Moreover, asthma that appears later in life has been also linked to CVD. The associations between asthma and CVD are incompletely understood, but chronic and systemic inflammation derived from the airways may have a role in the development of the atherosclerosis and hypercoagulable states. Additionally, eosinophils, smooth muscle factors, endothelial dysfunction and haemodynamic stress may be important factors that link asthma and CVD. These observations have raised clinical awareness and may identify asthmatics with a higher risk profile for CVD, opening an opportunity for potential interventions in the earlier stages of the disease.
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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.

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.