Bang for the Buck: Intensifying the Focus on Cardiogenic Shock in Order to Reduce Mortality in Acute Coronary Syndromes
Last Updated: July 17, 2020
Care for patients with acute cardiac disease has been characterized by a vigorous focus on patients with acute ST segment elevation myocardial infarction (STEMI). As a result, multiple organizations have motivated health care systems and regional health authorities to make drastic changes that have reduced the time between patient presentation and reperfusion therapy (largely primary PCI), with the effect that patient-specific mortality has been reduced, even though population mortality has changed little1. During this same period, the proportion of patients with myocardial infarction presenting with cardiogenic shock (CS) has increased from 6% to 10%2, while the frequency of CS in patients with out of hospital cardiac arrest is approximately 50%. Conversely about 80% of patients with CS initially present with acute coronary syndromes3. These cases account for most of the deaths among patients presenting with myocardial infarction. Interestingly, most patients who survive the acute phase of CS are alive one to six years later4,5. The Should We Emergently Revascularize Occluded Coronaries for Cardiogenic Shock (SHOCK) trial established that reperfusion reduced mortality in patients with CS complicating myocardial infarction6. Little progress has been made since then, however. Despite improved understanding of the pathophysiology of CS, mortality remains high – about 39% for patients < 75 years and 55% for those aged 75 or older2. Importantly, the relatively easy to implement strategies such as intraaortic balloon counterpulsation and novel pharmacologic approaches alone have not been successful in reducing shock mortality7,8. Data have accumulated from reports of more advanced mechanical support devices such as the Impella, suggesting strongly that early implementation of mechanical support may be associated with lower mortality9. These data and other aspects of pharmacologic and mechanical management of CS are reviewed in great detail in the current AHA/ASA Scientific Statement on Contemporary Management of Cardiogenic Shock10.
In addition, the statement makes a number of critically important points that are bound to attract attention. They are largely based on the assumption that earlier treatment and more closely coordinated care of patients with CS is likely to lead to the next round of mortality reduction.
- Early recognition of CS, including its less common presentations, is essential. The classical “wet and cold” (high filling pressure with peripheral vasoconstriction) picture is most common, but is not the only presentation of CS. Practitioners should be aware of “cold and dry” and normotensive presentations as well as right ventricular shock. Another important point is that although the classic teaching has been that mechanical complications occur late in the course of myocardial infarction, ample evidence now demonstrates that they frequently occur early after presentation11.
- Following recognition, the application of various scoring systems, such as APACHE III may be useful in selecting patients for more advanced therapeutic strategies.
- There is a graded relationship between center experience at managing CS and mortality of the syndrome, likely as a result of more frequent use of established therapies, availability of high volume PCI operators, and multidisciplinary management teams. After adjustment for baseline risk, CS mortality was reported to be approximately 27% lower when patients were managed in the highest compared with the lowest volume centers, even though the former group constituted only 3.2% of the hospitals studied12.
- Developing systems of care based on regional designation as specialized receiving centers has been successful in other serious illnesses whose outcomes are dependent on time to treatment, such as stroke, trauma, and out of hospital cardiac arrest. Such systems have also shorted reperfusion times for patients with STEMI. Early experience among surgical patients with post cardiotomy shock and in a French ambulance-based pilot trial13 has suggested that developing a similar system for shock may be useful. Such a system would necessarily be more complex than that used for STEMI as the number of centers would necessarily be smaller. The Statement proposes establishing specialized receiving centers, which would meet the following criteria:
- Minimal Level 1 organizational standards as proposed in the 2012 AHA Scientific Statement Evolution of Critical Care Cardiology. Such standards include the capability of managing “all cardiovascular conditions and major noncardiovascular comorbid conditions14.
- Multidisciplinary “Shock teams” consisting of cardiac surgeons, interventional cardiologists, advanced heart failure specialists, critical care specialists, transplantation teams, and other health professionals. This team must be able to select and implant appropriate circulatory support devices, perform complex revascularizations of coronary arteries that have not been addressed during primary PCI, manage the complex renal, respiratory and metabolic derangements that accompany CS and in many circumstances, perform triage to palliative care.
- Dedicated ICUs for patients with CS, which would be distinct from standard cardiac care units. Obviously developing such units would vary from hospital to hospital as dictated by available space and other logistic considerations.
- Availability 24 hours, 7 days a week with 30 minute response times to incoming phone calls
- In certain situations, mobile CS support teams that are able to stabilize and transport patients to Level 1 facilities.
- Extension of the AHA Mission Lifeline to include support for these recommendations. In the decade since its implementation, this initiative has demonstrated major success in promoting the proportion of patients with STEMI who receive timely reperfusion therapy.
These recommendations are perfectly logical and are fairly well, although imperfectly, supported by the existing evidence. It is important to recognize, though, that they will require fundamental changes in the way business is currently conducted. First, the recommendations would establish a three-tier system of managing CS, consisting of a primary hospital, a local PCI-capable hospital, and a designated “hub” institution. Currently, according to NCDR data, fewer than one out of four cases of CS are managed at high volume hospitals15. Revascularization will still need to be performed in the most rapid fashion possible. Once a primary PCI is performed, emphasis would shift to a formal assessment of the patient’s risk of developing CS and making plans for immediate transfer from “spoke” to “hub” hospitals when this risk is high. Unlike, the current approach, the third tier of care would become systematized, as the number of CS receiving hospitals would be considerably smaller due to the resources required to manage the 10% of infarctions in which CS develops. Adopting this mechanism would likely prove contentious as it would require alterations in referral patterns and would probably spur competition for designation as hub centers. Second, careful examination of the financial implications of this strategy will be required, as management of patients in CS is extremely resource-intensive and is likely to pose a burden on the spoke hospitals. Finally, as proposed in the statement alteration in the current public reporting system so that receiving centers are not penalized for managing these patients and do not become risk-averse. Precedent for this approach exists in some states in the US.
The hypothesis is clear – that a systematic approach to CS will reduce morbidity and mortality of the syndrome. The proof isn’t so clear – will such a strategy really work, and what will its downstream effects be? Surely a series of pilot studies is in order.
Citation
van Diepen S, Katz JN, Albert NM, Henry TD, Jacobs AK, Kapur NK, Kilic A, Menon V, Ohman EM, Sweitzer NK, Thiele H, Washam JB, Cohen MG; on behalf of the American Heart Association Council on Clinical Cardiology; Council on Cardiovascular and Stroke Nursing; Council on Quality of Care and Outcomes Research; and Mission: Lifeline. Contemporary management of cardiogenic shock: a scientific statement from the American Heart Association [published online ahead of print September 18, 2017]. Circulation. doi: 10.1161/CIR.0000000000000525.
References
- Nallamothu BK, Normand SL, Wang Y, Hofer TP, Brush JE, Jr., Messenger JC, Bradley EH, Rumsfeld JS, Krumholz HM. Relation between door-to-balloon times and mortality after primary percutaneous coronary intervention over time: a retrospective study. Lancet. 2015;385: 1114-1122.
- Kolte D, Khera S, Aronow WS, Mujib M, Palaniswamy C, Sule S, Jain D, Gotsis W, Ahmed A, Frishman WH, Fonarow GC. 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.
- Harjola VP, Lassus J, Sionis A, Kober L, Tarvasmaki T, Spinar J, Parissis J, Banaszewski M, Silva-Cardoso J, Carubelli V, Di Somma S, Tolppanen H, Zeymer U, Thiele H, Nieminen MS, Mebazaa A. Clinical picture and risk prediction of short-term mortality in cardiogenic shock. Eur J Heart Fail. 2015;17:501-509.
- Hochman JS, Sleeper LA, Webb JG, Dzavik V, Buller CE, Aylward P, Col J, White HD. Early revascularization and long-term survival in cardiogenic shock complicating acute myocardial infarction. JAMA. 2006;295:2511-2515.
- Shah RU, de Lemos JA, Wang TY, Chen AY, Thomas L, Sutton NR, Fang JC, Scirica BM, Henry TD, Granger CB. Post-Hospital Outcomes of Patients With Acute Myocardial Infarction With Cardiogenic Shock: Findings From the NCDR. J Am Coll Cardiol. 2016;67:739-747.
- Hochman JS, Sleeper LA, Webb JG, Sanborn TA, White HD, Talley JD, Buller CE, Jacobs AK, Slater JN, Col J, McKinlay SM, LeJemtel TH. 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.
- Thiele H, Zeymer U, Neumann FJ, Ferenc M, Olbrich HG, Hausleiter J, Richardt G, Hennersdorf M, Empen K, Fuernau G, Desch S, Eitel I, Hambrecht R, Fuhrmann J, Bohm M, Ebelt H, Schneider S, Schuler G, Werdan K. Intraaortic balloon support for myocardial infarction with cardiogenic shock. N Engl J Med. 2012;367:1287-1296.
- Alexander JH, Reynolds HR, Stebbins AL, Dzavik V, Harrington RA, Van de Werf F, Hochman JS. Effect of tilarginine acetate in patients with acute myocardial infarction and cardiogenic shock: the TRIUMPH randomized controlled trial. JAMA. 2007;297:1657-1666.
- Basir MB, Schreiber TL, Grines CL, Dixon SR, Moses JW, Maini BS, Khandelwal AK, Ohman EM, O'Neill WW. Effect of Early Initiation of Mechanical Circulatory Support on Survival in Cardiogenic Shock. Am J Cardiol. 2017;119:845-851.
- van Diepen S, Katz JN, Albert NM, Henry TD, Jacobs AK, Kapur NK, Kilic A, Menon V, Ohman EM, Sweitzer NK, Thiele H, Washam JB, Cohen MG; on behalf of the American Heart Association Council on Clinical Cardiology; Council on Cardiovascular and Stroke Nursing; Council on Quality of Care and Outcomes Research; and Mission: Lifeline. Contemporary management of cardiogenic shock: a scientific statement from the American Heart Association [published online ahead of print September 18, 2017]. Circulation. doi: 10.1161/CIR.0000000000000525.
- Menon V, Webb JG, Hillis LD, Sleeper LA, Abboud R, Dzavik V, Slater JN, Forman R, Monrad ES, Talley JD, Hochman JS. Outcome and profile of ventricular septal rupture with cardiogenic shock after myocardial infarction: a report from the SHOCK Trial Registry. SHould we emergently revascularize Occluded Coronaries in cardiogenic shocK? J Am Coll Cardiol. 2000;36:1110-1116.
- Shaefi S, O'Gara B, Kociol RD, Joynt K, Mueller A, Nizamuddin J, Mahmood E, Talmor D, Shahul S. Effect of cardiogenic shock hospital volume on mortality in patients with cardiogenic shock. J Am Heart Assoc. 2015;4:e001462.
- Beurtheret S, Mordant P, Paoletti X, Marijon E, Celermajer DS, Leger P, Pavie A, Combes A, Leprince P. Emergency circulatory support in refractory cardiogenic shock patients in remote institutions: a pilot study (the cardiac-RESCUE program). Eur Heart J. 2013;34:112-120.
- Morrow DA, Fang JC, Fintel DJ, Granger CB, Katz JN, Kushner FG, Kuvin JT, Lopez-Sendon J, McAreavey D, Nallamothu B, Page RL, 2nd, Parrillo JE, Peterson PN, Winkelman C. Evolution of critical care cardiology: transformation of the cardiovascular intensive care unit and the emerging need for new medical staffing and training models: a scientific statement from the American Heart Association. Circulation. 2012;126:1408-1428.
- Wayangankar SA, Bangalore S, McCoy LA, Jneid H, Latif F, Karrowni W, Charitakis K, Feldman DN, Dakik HA, Mauri L, Peterson ED, Messenger J, Roe M, Mukherjee D, Klein A. Temporal Trends and Outcomes of Patients Undergoing Percutaneous Coronary Interventions for Cardiogenic Shock in the Setting of Acute Myocardial Infarction: A Report From the CathPCI Registry. JACC Cardiovasc Interv. 2016;9:341-351.
Science News Commentaries
-- The opinions expressed in this commentary are not necessarily those of the editors or of the American Heart Association --
Pub Date: Monday, Sep 18, 2017
Author: Neal S. Kleiman, MD, FAHA
Affiliation: Houston Methodist DeBakey Heart and Vascular Center, Weill Cornell Medical College