Cardiogenic Shock Management: International Survey of Contemporary Practices

Abstract: Background. Limited data exist on current cardiogenic shock (CS) management strategies. Methods. A 48-item open- and closed-ended question survey on the diagnosis and management of CS. Result. A total of 211 respondents (3.2%) completed the survey, including 64% interventional cardiologists, 14% general cardiologists, 11% advanced heart failure cardiologists, 5% intensivists, 3% cardiothoracic surgeons; the remainder were internists, emergency medicine, and other physicians. Nearly half (45%) reported practicing at sites without advanced heart failure support/resources, with neither durable ventricular assist devices nor heart transplant available; 16% practice at sites without on-site cardiac surgery and 6% do not offer 24/7 percutaneous coronary intervention (PCI) coverage. The majority (70%) practice in closed intensive care units with multidisciplinary rounding (73%), cardiologists frequently involved in patient care (89%), and involving cardiology-intensivist co-management (41%). Over half (55%) reported use of CS protocols, 61% reported routine arterial line use, 25% reported routine use of pulmonary artery catheter use to guide management and 9% did not. The preferred vasopressor and/or inotrope was norepinephrine (68%). For coronary angiography and PCI, 53% use transradial access, 72% only revascularize the culprit vessel, and 44% institute mechanical circulatory support (MCS) prior to revascularization. Percutaneous MCS availability was as follows: intra-aortic balloon pump (92%), Impella (78%), peripheral veno-arterial extracorporeal membrane oxygenation (66%), and TandemHeart (28%). Most respondents (58%) do not use a scoring system for risk stratification and most (62%) reported that CS-specific cardiac rehabilitation programs were unavailable at their sites. Conclusion. Wide variation exists in the care delivered and/or resources available for patients with CS. Our survey suggests opportunities for standardization of care.

J INVASIVE CARDIOL 2020;32(10):371-374. 

Key words: heart failure, mechanical circulatory support, risk stratification, shock

Cardiogenic shock (CS) is a complex, low cardiac output state resulting in critical end-organ hypoperfusion. It remains the leading cause of in-hospital mortality following acute myocardial infarction (AMI).^1-6 Despite advances in therapeutic options and recent studies suggesting improved outcomes using a standardized-team based approach to patient care, variations exist in time to diagnosis, management, and resource availability, such as hemodynamic monitoring, mechanical circulatory support (MCS), and treatment by multidisciplinary teams.^7-14 We performed an online survey to better understand contemporary diagnostic and treatment strategies for CS patients. 

Methods

We designed an open- and closed-ended survey and circulated a link to a 48-item questionnaire (Supplemental Table S1) via email (the email list was obtained from the Cardiovascular Innovations Foundation, which is a non-profit organization) and social media (Twitter), including interventional cardiologists, general cardiologists, advanced heart failure cardiologists, intensivists, and cardiovascular surgeons. The survey was open between March 2019 and May 2019. Following study completion, anonymized summary data and individual responses were examined using an online survey development cloud-based software (SurveyMonkey, Inc). Funding for SurveyMonkey was provided by the Minneapolis Heart Institute Foundation.

Results

The survey was circulated to 6683 physicians, of whom 211 (3.2%) completed the survey. Respondents were mostly interventional cardiologists (64%), followed by general cardiologists (14%), advanced heart failure cardiologists (11%), intensivists (or pulmonary critical care specialists) (5%), cardiothoracic surgeons (3%), and other (3%). The location of practice for the participants was not obtained due to institutional review board restriction. Summary data for the entire completed survey are provided in Supplemental Table S1. 

Over half of the respondents (68%) care for CS patients on a regular basis (at least once every 1-2 weeks). Approximately 40% have access to all types of hemodynamic support, including inotropes, intra-aortic balloon pump (IABP), Impella, durable ventricular-assist device (VAD), as well as heart transplantation. Approximately 21% practice at centers in which only percutaneous coronary intervention (PCI) and IABP are available. Regarding CS patient transfers from other centers, 63% of respondents stated that such patients are always accepted, whereas 30% indicated selective acceptance. Almost 70% of respondents practice in closed intensive care units (ICUs) and 78% work in cardiovascular-specific ICUs. CS patients are managed mainly by cardiologists (32%) or by a team of intensivists and cardiologists (41%). Multidisciplinary rounds were conducted in 73%.

General management. Most respondents (94%) practice at centers where 24-hour percutaneous coronary intervention (PCI) is available and 84% have cardiac surgery on site. Approximately half of the respondents (55%) have an established CS algorithm or protocol for management. Only 25% routinely use invasive circulatory monitoring systems (eg, pulmonary artery catheter [PAC]); however, an additional 36% report use in most, but not all patients. Similarly, 61% report routine use of an arterial line for guidance, with an additional 28% reporting use in most, but not all patients. Hemodynamic indices, such as cardiac power output (CPO), pulmonary artery pulsatility index (PAPi), or tricuspid annular plane excursion (TAPSE), are calculated routinely by 57% of respondents. Lactate measurements are used by 87% to guide management. More than half of the respondents use a mean arterial pressure (MAP) of 60 mm Hg as a threshold for initiating hemodynamic support. Norepinephrine is the first-line vasopressor for 68%, followed by dobutamine (15%) and dopamine 8%. Over half of the respondents (58%) do not use any scoring system for predicting clinical outcomes in CS patients; among those who do, the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) score is preferred in 28%, followed by the Acute Physiology And Chronic Health Evaluation (APACHE) II score in 10%. Beta-blockers or angiotensin-receptor inhibitors are initiated by approximately half of respondents (49%) within the first 24 hours after resolution of CS and statins in 68%. Regarding cardiac arrest, the majority of respondents (82%) have resuscitation time cut-offs when considering MCS. 

Revascularization. Radial artery is the preferred access site for PCI in 53%. When revascularization is needed, 72% perform culprit-lesion only revascularization. In patients presenting with ST-segment elevation myocardial infarction (STEMI) and CS, 66% initiate MCS (Impella, extracorporeal membrane oxygenation [ECMO], or IABP) prior to performing revascularization.

Mechanical circulatory support. Forty-five percent of respondents consider MCS when response is not optimal with 2 vasopressors and 43% consider MCS based on PAC measurements of cardiac output (or cardiac power). Regarding types of MCS, Impella is the preferred device in 48% of respondents, IABP in 44%, and veno-arterial (VA)-ECMO in 8%. MCS is initiated before PCI in 44% and its initiation is dependent of hemodynamics. VA-ECMO is placed by interventional cardiologist in the cardiac catheterization laboratory in 29%, by surgeons in the operating room in 24%, and in the ICU or emergency department by cardiologists, intensivists, or emergency physicians in the remaining centers. If left ventricular venting is needed in CS-ECMO, 41% prefer Impella and 24% prefer IABP. 

Discussion

Our survey offers novel insights into the contemporary management of CS, demonstrating significant variation in diagnostic and treatment strategies and access to resources. 

A substantial proportion of respondents have limited or no access to several resources that are part of the contemporary CS armamentarium. Over 20% of respondents indicated that they practice at sites in which only inotropes and IABP are available, approximately 6% practice at hospitals that do not provide around-the-clock PCI coverage, and 16% do not have cardiac surgery back-up. Hence, several hospitals likely do not meet the 2017 American Heart Association CS center designation.⁴ 

Several respondents do not routinely care for CS patients. Only approximately half of the respondents use invasive hemodynamics (PAC) to guide management, with only 25% reporting routine use and 57% reporting use of a validated hemodynamic indices such as CPO or PAPi. Most contemporary CS management algorithms recommend a multidisciplinary approach and integration of invasive hemodynamics in the care of CS patients. In addition, only half of the respondents report use of an established algorithm in the care for CS patients, and over half (58%) do not use a scoring system to predict clinical outcomes. 

Most respondents manage CS patients on a regular basis, have access to MCS devices, and treat CS patients in closed ICUs. The treatment team consists of a cardiologist or a cardiologist working together with an intensivist. Prior studies have reported improved outcomes in a closed-unit model, and delivery of care by dual-trained cardiologist-intensivists.^15,16 

When revascularization is needed for CS patients, the preferred arterial access is the radial artery in 53% and culprit-only revascularization is performed by 72% of respondents following the results of the CULPRIT-SHOCK (Culprit Lesion Only PCI vs Multivessel PCI in Cardiogenic Shock) trial.¹⁷ In those presenting with STEMI-CS, 66% of respondents place MCS prior to revascularization. 

Approximately half of respondents use MCS when hemodynamic response to 2 vasopressors/inotropes is inadequate, whereas the other half place MCS based on cardiac output goals. Impella is used more often (48%), followed by IABP (44%) and VA-ECMO (8%). The need and type of MCS for CS patients remains controversial. The IABP-SHOCK II (Intraortic Balloon Support for Myocardial Infarction With Cardiogenic Shock) trial found no difference with routine IABP use in CS patients; hence, IABP use was downgraded to a class IIIA recommendation in the most recent European revascularization and non-ST elevation acute coronary syndromes guidelines.^1,16,18-20 Data on MCS are quite limited. Outcomes were worse among CS patients treated with Impella in a recent retrospective study.²¹ The DanGer Shock (Danish-German Cardiogenic Shock; NCT01633502) trial is randomizing CS patients to conventional circulatory support or the Impella CP device. VA-ECMO may be required due to cardiac failure, respiratory failure, or a combination of both. In our survey, VA-ECMO is used by 8% of the respondents and is usually placed by interventional cardiologists (29%) or by surgeons in the operating room (24%). Relative contraindications and potential complications of VA-ECMO must be taken into consideration.²² Currently, there are no published randomized control trials assessing the clinical effectiveness of VA-ECMO in CS, although 3 trials are currently ongoing: (1) Euro-Shock (Testing the Value of Novel Strategy and its Cost Efficacy in Order to Improve the Poor Outcomes in Cardiogenic Shock; NCT03813134), (2) ANCHOR (Assessment of ECMO in Acute Myocardial Infarction Cardiogenic Shock; NCT04184635); and (3) ECLS-SHOCK (Extracorporeal Life Support in Cardiogenic Shock; NCT03637205).

Study limitations. Our study has a few limitations. First, the questionnaire for this survey is not validated. Second, the response rate was low. Third, 64% of the respondents are interventional cardiologists, so the findings may not fully reflect the practices of other key members of the multidisciplinary CS team. Fourth, most of the respondents (68%) treat CS patients on a regular basis, so the results may not apply to physicians treating CS patients infrequently. Fifth, the countries of origin of the participants were not collected.

Conclusion

Our survey suggests wide variation in the care delivered to CS patients, highlighting the need for consensus building and standardization. The limited use of CS treatment protocols and frequent lack of a full complement of advanced heart failure therapy options in centers treating CS patients indicates the need for educational efforts to inform clinicians on contemporary, multidisciplinary strategies to manage CS patients, and highlights the importance of developing hub and spoke models for transferring patients to centers able to provide advanced therapies for patients who do not respond to initial management. 

From the ¹Department of General Internal Medicine, Mayo Clinic, Rochester, Minnesota; ²Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minnesota; ³Academic Medical Center – University of Amsterdam, Amsterdam, The Netherlands; ⁴Division of Cardiovascular Medicine, University of Utah School of Medicine, Salt Lake City, Utah; ⁵Vanderbilt University Medical Center, Nashville, Tennessee; ⁶Cardiovascular Division, Department of Medicine, University of Miami Miller School of Medicine, Miami, Florida; ⁷Cardiovascular Division, University of Nebraska Medical Center, Omaha, Nebraska; ⁸Minneapolis Heart Institute, Abbott Northwestern Hospital, Minneapolis, Minnesota; and ⁹Leipzig Heart Center at University of Leipzig, Department of Internal Medicine/Cardiology, Leipzig, Germany.

Disclosure: The authors have completed and returned the ICMJE Form for Disclosure of Potential Conflicts of Interest. Dr Sandoval reports advisory board/speaker board without personal financial compensation for Abbott Diagnostics; past member of the advisory board without personal financial compensation for Roche Diagnostics. Dr Henriques reports research funding from Abbott Vascular and AstraZeneca. Dr Cohen reports consultant income from Abiomed, Medtronic, AstraZeneca, and Merit Medical. Dr Chatzizisis reports speaker honoraria, advisory board fees, and research grant from Boston Scientific; grant support from Medtronic. Dr Drakos reports consulting income from Abbott. Dr Brilakis reports consulting/speaker honoraria from Abbott Vascular, American Heart Association (associate editor, Circulation), Boston Scientific, Cardiovascular Innovations Foundation (Board of Directors), CSI, Elsevier, GE Healthcare, InfraRedx, and Medtronic; research support from Regeneron and Siemens; shareholder in MHI Ventures; Board of Trustees for the Society of Cardiovascular Angiography and Interventions. The remaining authors report no conflicts of interest regarding the content herein. 

Manuscript accepted April 9, 2020.

Address for correspondence: Emmanouil S. Brilakis, MD, PhD, Minneapolis Heart Institute, 920 East 28th Street #300, Minneapolis, MN 55407. Email: esbrilakis@gmail.com

1. Bagai J, Brilakis ES. Update in the management of acute coronary syndrome patients with cardiogenic shock. Curr Cardiol Rep. 2019;4:21:17.
2. Thiele H, Ohman EM, Desch S, Eitel I, de Waha S. Management of cardiogenic shock. Eur Heart J. 2015;36:1223-1230.
3. Thiele H, Zeymer U, Neumann FJ, et al. Intraaortic balloon support for myocardial infarction with cardiogenic shock. N Engl J Med. 2012;367:1287-1296.
4. Van Diepen S, Katz JN, Albert NM, et al. Contemporary management of cardiogenic shock: a scientific statement from the American Heart Association. Circulation. 2017;136:e232-268.
5. Baran DA, Grines CL, Bailey S, et al. SCAI clinical expert consensus statement on the classification of cardiogenic shock: this document was endorsed by the American College of Cardiology (ACC), the American Heart Association (AHA), the Society of Critical Care Medicine (SCCM), and the Society of Thoracic Surgeons (STS) in April 2019. Catheter Cardiovasc Interv. 2019;94:29-37.
6. Samsky M, Krucoff M, Althouse AD, et al. Clinical and regulatory landscape for cardiogenic shock: a report from the Cardiac Safety Research Consortium Thinktank on Cardiogenic Shock. Am Heart J. 2019;219:1-8.
7. Kolte D, Khera S, Aronow WS, et al. Trends in incidence, management, and outcomes of cardiogenic shock complicating ST-elevation myocardial infarction in the United States. J Am Heart Assoc. 2014;3:e000590.
8. Sandhu A, McCoy LA, Negi SI, et al. Use of mechanical circulatory support in patients undergoing percutaneous coronary intervention: insights from the National Cardiovascular Data Registry. Circulation. 2015;132:1243-1251.
9. Shaefi S, O’Gara B, Kociol RD, et al. Effect of cardiogenic shock hospital volume on mortality in patients with cardiogenic shock. J Am Heart Assoc. 2015;4:e001462.
10. Tehrani BN, Truesdell AG, Sherwood MW, et al. Standardized team-based care for cardiogenic shock. J Am Coll Cardiol. 2019;73:1659-1669.
11. Taleb I, Koliopoulou AG, Tandar A, et al. Shock team approach in refractory cardiogenic shock requiring short-term mechanical circulatory support: a proof of concept. Circulation. 2019;140:98-100.
12. Basir MB, Schreiber T, Dixon S, et al. Feasibility of early mechanical circulatory support in acute myocardial infarction complicated by cardiogenic shock: the Detroit Cardiogenic Shock Initiative. Catheter Cardiovasc Interv. 2018;91:454-461.
13. Hryniewicz K, Sandoval Y, Samara Y, et al. Percutaneous venoarterial extracorporeal membrane oxygenation for refractory cardiogenic shock is associated with improved short- and long-term survival. ASAIO J. 2016;62:397-402.
14. Hochman JS, Sleeper LA, Webb JG, et al. Early revascularization in acute myocardial infarction complicated by cardiogenic shock. SHOCK Investigators. Should we emergently revascularize occluded coronaries for cardiogenic shock. N Engl J Med. 1999;341:625-634.
15. Pronovost PJ, Angus DC, Dorman T, et al. Physician staffing patterns and clinical outcomes in critically ill patients: a systematic review. JAMA. 2002;288:2151-2162.
16. Na SJ, Chung CR, Jeon K, et al. Association between presence of a cardiac intensivist and mortality in an adult cardiac care unit. J Am Coll Cardiol. 2016;68:2637-2648.
17. Thiele H, Akin I, Sandri M, et al. PCI strategies in patients with acute myocardial infarction and cardiogenic shock. N Engl J Med. 2017;377:2419-2432. 
18. Abdel-Wahab M, Saad M, Kynast J, et al. Comparison of hospital mortality with intra-aortic balloon counterpulsation insertion before versus primary percutaneous coronary intervention for cardiogenic shock complicating acute myocardial infarction. Am J Cardiol. 2010;105: 967-971.
19. Thiele H, Zeymer U, Thelemann N, et al. Intraaortic balloon pump in cardiogenic shock complicating acute myocardial infarction: long-term 6-year outcome of the randomized IABP-SHOCK II trial. Circulation. 2019;139:395-403.
20. Cheng JM, van Leeuween MA, de Boer SP, et al. Impact of intra-aortic balloon pump support initiated before versus after primary percutaneous coronary intervention in patients with cardiogenic shock from acute myocardial infarction. Int J Cardiol. 2013;168:3758-3763.
21. Amin AP, Spertus JA, Curtis JP, et al. The evolving landscape of Impella® use in the United States among patients undergoing percutaneous coronary intervention with mechanical circulatory support. Circulation. 2020;141:273-284. Epub 2019 Nov 17.
22. Eckman PM, Katz JN, El Banayosy A, Bohula EA, Sun B, van Diepen S. Veno-arterial extracorporeal membrane oxygenation for cardiogenic shock: an introduction for the busy clinician. Circulation. 2019;140:2019-2037.