The Role of Percutaneous Mechanical Circulatory Support Devices in High-Risk Percutaneous Coronary Interventions

¹Division of Cardiology, Department of Internal Medicine, University of Missouri School of Medicine, Columbia, Missouri; ²Harry S Truman Veterans Hospital, Columbia, Missouri

Disclosures: Dr. Harsh Agrawal and Dr. Kul Aggarwal report no conflicts of interest regarding the content herein.

Harsh Agrawal MD, FACP, can be contacted at harshagrawal@hotmail.com.
Kul Aggarwal MD, FACC, Director, Cardiac Catheterization Lab, Truman VA Medical Center; Professor of Medicine, University of Missouri School of Medicine, can be contacted at aggarwalk@health.missouri.edu.

A condensed version of this article was published originally in Agrawal H, Aggarwal K. Mechanical circulatory support in percutaneous coronary interventions: expanding the possibilities. J Invasive Cardiol. 2016 Jun; 28(6): 243-245 and any text is reprinted with permission from HMP Communications.

Introduction

Percutaneous coronary interventions (PCI) have increased both in number and complexity in the last two decades. Tackling complex coronary lesions in patients who have reduced coronary and central perfusion pressures, depressed cardiac output, and increased myocardial oxygen demand has led to greater use of mechanical circulatory support devices. An intra-aortic balloon pump (IABP) was one of the first mechanical circulatory support devices to be used for coronary revascularization in patients with cardiogenic shock.¹ Since then, several other percutaneous ventricular assist devices (PVADs) have been developed, such as the Impella (Abiomed), TandemHeart (CardiacAssist, now TandemLife), and extracorporeal membrane oxygenation (ECMO). Other temporary MCS devices that require a median sternotomy for placement include the BVS 5000 (Abiomed), CentriMag and Thoratec percutaneous ventricular assist device (pVAD) (both from Thoratec Corporation/St. Jude Medical), all of which can provide mechanical circulatory support in patients undergoing high-risk PCI (Table 1).

Patient, lesion, and hemodynamic factors are all taken into consideration when planning a high-risk PCI. Examples of high-risk PCI include unprotected left main interventions, a proximal artery supplying large amount of myocardium, patients with left ventricular (LV) dysfunction, status post cardiac arrest, incessant ventricular tachycardia, and ST elevation myocardial infarction (STEMI) with shock. 

In a recent CathPCI registry analysis of 56,497 patients with acute myocardial infarction (AMI) complicated with cardiogenic shock (CS) revealed increased in-hospital mortality from 27.6% in 2005 to 2006, to 30.6% in 2011 to 2013 (P<0.01)², possibly indicating the increased complexity of patients presenting with AMI and CS. Of the 1,249,547 PCI procedures performed between July 2009 and June 2011 in the United States, 17% were emergent cases.³ The American College of Cardiology/American Heart Association/Society for Cardiovascular Angiography and Interventions (ACC/AHA/SCAI) guidelines support the use of these devices in various settings, including hemodynamic support during high-risk PCI, patients presenting with cardiogenic shock as a bridge to recovery, or during revascularization.^4-6 Despite widespread use and availability of these devices, there is a paucity of randomized, controlled trials data demonstrating unequivocal superiority of these devices in the aforementioned settings.^7-9 A contemporary review by the Interventional Scientific Council of the ACC outlines an elegant algorithm providing various scenarios where use of mechanical circulatory support may be appropriate and helpful in patients undergoing high-risk PCI with CS.¹⁰ The Council recommends a heart team approach, including interventional cardiologists, cardiothoracic surgeons, intensivists, and heart failure specialists, for pre and post procedure device management for high-risk patients. In this review, we discuss the contemporary evidence regarding the use of mechanical circulatory support in the current PCI era. 

Intra-aortic balloon pump (IABP)

The IABP has been the most widely used mechanical circulatory support in the recent era.¹¹ It is placed in the descending aorta between the aortic arch vessels and the renal arteries, and it augments diastolic coronary artery perfusion by balloon inflation (Figure 1).¹² An IABP also reduces afterload by balloon deflation during the isovolumetric contraction phase of the cardiac cycle, thus creating a vacuum effect in the aorta and helping systolic unloading, reducing left ventricular work and myocardial oxygen demand, and increasing the cardiac output.¹³  

A recent National Inpatient Sample (NIS) database registry analysis¹⁴ estimated 122,333 IABPs were inserted for patients undergoing same-day PCIs in the United States from 2004 to 2012, a statistically significant increase from previous years. In this population, patients with an IABP as compared to other PVADs were more likely to have an acute MI or cardiogenic shock. Patients who received an IABP had a higher mortality in the unadjusted analysis; however, this difference was no longer seen in the propensity-matched analysis (odds ratio [OR] for PVAD group 0.90, 95% confidence interval [CI] 0.70 to 1.16, P=0.40). Data from the ACC’s National Cardiovascular Data Registry (NCDR) looking at IABP use in high-risk PCI (defined as unprotected left main artery stenting, cardiogenic shock, LV function <30%, or STEMI) demonstrated no mortality benefit of IABP use in this population across all quartiles of hospitals with high and low IAPB usage.¹⁵ The SHOCK trial16 enrolled 302 patients with LV dysfunction due to MI. Eighty-six percent of all patients who were randomly assigned to revascularization vs medical stabilization received hemodynamic support with an IABP. A 6-month mortality benefit was seen in the revascularization arm (50.3% vs 63.1%; 95% CI -23.2 to -0.9%, P=0.027) along with a mortality benefit in the revascularization with IABP group in the post-hoc analysis.^17,18 Long-term results from the Balloon Pump-Assisted Coronary Intervention Study-119, a prospective, open, multicenter, randomized, controlled trial (RCT) are now available. Three hundred and one (301) patients with LV ejection fraction (LVEF) <30% and extensive myocardium at risk were assigned in a 1:1 fashion to receive PCI with IABP or PCI alone. Five-year follow-up shows survival benefit of elective IABP over the no-IABP group (hazard ratio 0.66 [95% CI, 0.44–0.98; P=0.039]). The IABP-SHOCK II trial²⁰ was an open-label, randomized trial of 600 patients with AMI complicated by CS. IABP-SHOCK II showed no mortality benefit in either of the groups who were assigned in a 1:1 fashion to revascularization with or without IABP support. The study had some limitations, including the use of vasopressors, mechanical ventilators for about 80% of the patients, and some patients may not have been sick enough to warrant pre-procedure IABP. The complication rate was similar between the two groups and 12-month follow-up did not reveal any differences in term of mortality between the two groups.²¹ Some smaller studies have shown mortality benefit for the use of pre-procedure IABP for high-risk PCIs with minimal complications.^22,23 Multiple meta-analyses have reflected the finding of the above trial and the registries.^24-27 

IABP holds a class IIB recommendation in the recent ACC/AHA/SCAI guidelines, to be used in selected high-risk patients.⁴ The European Society of Cardiology/European Association for Cardio-Thoracic Surgery (ESC/EACTS) have a class III A (harm) recommendation for the routine use of IABP in cardiogenic shock.²⁸

Percutaneous ventricular assist devices (PVADs)

PVADs consist of a group of mechanical circulatory support devices, as mentioned above. There has been a steady rise in the use of PVADs in the United States.^29,30 About a 1500% increase in the use of these devices was observed in 5 years, along with reduction in cost and mortality (P= 0.027).³¹ This is likely due to improved hemodynamic support as compared to an IABP. PVADs currently hold a class IIb indication, to be used both in patients with refractory CS and carefully selected, high-risk PCI patients.^4,5 In an analysis of the NIS database, Khera et al²⁹ found that the utilization of PVADs had increased 30-fold from 2007 to 2012. Compared to IABP, PVAD patients were more likely to have congestive heart failure and undergo PCI; however, in the propensity-matched analysis, PVADs were associated with higher mortality (odds ratio, 1.23 [95% CI, 1.06-1.43]; P=0.007).²⁹ When compared to IABP, use of PVADs from an NIS analysis of all patients undergoing PCI demonstrated a decreased mortality (P<0.001) and complications (OR 0.72, 0.65–0.79, P<0.001) rates.³⁰ PVADs had more vascular complications and mortality benefit was seen in patients who had no evidence of CS or AMI. Another recent NIS registry analysis, from 2004-2012, of patients who received mechanical circulatory support on the same day as the PCI, showed that PVADs were associated with lower in-hospital mortality in the unadjusted analysis (12.8% vs 20.9%, P<0.001) as compared to IABP; however, this benefit was not seen in the propensity-matched analysis.¹⁴ Romeo et al³² conducted a meta-analysis of  6 RCTs and 24 observational studies, totaling 15,799 patients. This meta-analysis compared IABP, PVADs, and medical therapy in AMI with CS patients, and IABP use was found to be associated with increased mortality. Similar to the meta-analysis by Cheng et al³³, Romeo et al confirmed that the use of PVAD was not associated with a survival benefit.^32,33 When used together, ECMO and IABP demonstrated a mortality benefit.³² As seen in other studies, PVAD patients were more likely to be older and had a higher burden of co-morbidities.^14,29,30 

a. Impella

Impella is a pigtail catheter-shaped device that helps in the unloading of the LV by sucking blood from the LV and transferring it to the ascending aorta. It is an axial, continuous-flow device that works independently of the heart rate or the LVEF. Use of the Impella leads to improved hemodynamics, including improving coronary flow velocity reserve, increasing mean arterial pressure, decreasing LV wall stress, decreasing microvascular coronary resistance, improved diastolic compliance, and supported myocardial recovery after AMI.^34-36 Three different forms of Impella devices are available. The Impella 2.5 LP and CP devices (Figures 2-4) provide up to 2.5 L/min and 3.5 L/min of estimated flow, respectively, while the Impella 5.0 (Figure 5) provides up to 5 L/min of estimated flow.  

A United States Impella registry analysis of 637 patients undergoing high-risk PCI with the Impella 2.5 observed that the mortality rate was at par with other studies at 2.8%, with no increase in complications and a significant decline in transfusion rates.³⁷ In the Impella EUROSHOCK registry³⁸, 120 patients with AMI and CS were placed on Impella 2.5 support. At 30 days, 77 of the 120 patients had died. The high mortality in this study is attributed to the enrollment of sicker patients than in other registries. Bleeding due to Impella insertion was a major complication in 34 patients. The ISAR-SHOCK³⁹ trial prospectively randomized patients with AMI and CS to either the Impella LP 2.5 or IABP, and measured cardiac index (CI) after 30 minutes as the primary endpoint. Change in CI was significantly higher in the Impella group (CI 0.49 ± 0.46 L/min/m²) than in patients with IABP (CI 0.11 ± 0.31 L/min/m²; P=0.02), but there was no difference in 30-day mortality. The PROTECT II study⁸ prospectively randomized 452 patients undergoing high-risk PCI and with a depressed ejection fraction to Impella 2.5 and IABP comparing major adverse events (MAE) at discharge or at 30-day follow-up. The trial was stopped early, after 69% of the patients were enrolled, due to futility. However, at 90 days, in the per protocol analysis, the Impella group had significantly fewer MAEs (40.0% vs 51.0%, P=0.023), with a relative risk reduction of 22%. Incidence of repeat revascularization was also significantly lower in the Impella group at 90 days and there were no differences in complication rates in either group. A study comparing Impella 2.5 versus Impella 5.0 in STEMI patients with CS suggested that Impella 5.0 may be associated with better outcomes specifically after upgrading from Impella 2.5 to 5.0.⁴⁰  

b. TandemHeart 

The TandemHeart is an extracorporeal centrifugal flow pump providing LV unloading via a left atrial to femoral arterial bypass, achieved through a venous transseptal inflow cannula that drains oxygenated blood from the left atrium and transfers it to the femoral artery via a femoral arterial catheter (Figures 6A-B). Pre-procedure aortoiliac angiography has been recommended to avoid any foreseeable vascular complications. The TandemHeart has the ability to pump 3-5 liters/minute and can augment cardiac output, and decrease preload and oxygen consumption depending on the placement of the outflow cannula in the ascending vs the descending aorta.^41,42 In a study that randomized 41 patients with AMI and CS, use of a PVAD was associated with improved cardiac output, pulmonary artery wedge pressure, cardiac power index, and reduced lactate levels as compared to an IABP.⁹ The PVAD group had more complications such as severe bleeding and limb ischemia, associated with complex procedural techniques used for insertion; however, there was no difference in mortality in either group. Burkhoff et al⁷ randomized 30 AMI with CS patients to TandemHeart (n=19) vs IABP (n=14). Although there was no significant survival benefit, TandemHeart was associated with improved hemodynamic parameters, with more bleeding in the TandemHeart group. Argon et al demonstrated short-term feasibility and safety of TandemHeart in a case series of 8 patients with LV dysfunction undergoing high-risk PCI.⁴³ Retrospective analysis of 74 high-risk PCIs with TandemHeart support at Texas Heart Institute demonstrated that it is a viable option in patients across the spectrum of coronary artery disease who are undergoing high-risk PCI.⁴⁴ Mayo Clinic reported 90% 30-day survival and 13% vascular complications in 54 patients undergoing high-risk PCI with TandemHeart.⁴⁵ Multiple single-center studies have demonstrated safety, feasibility, and an improved hemodynamic support profile with TandemHeart in patients undergoing high-risk PCI with a depressed LVEF, representing a prohibitive surgical risk group requiring more support than is provided by standard IABP.^46-52 

c. ECMO

ECMO uses a centrifugal pump to direct blood from the patient to an external system for gaseous exchange of carbon dioxide and oxygen, and then returns oxygenated blood back to the patient’s arterial system (Figure 7). Two ECMO systems are available, including veno-arterial (VA-ECMO) and veno-venous (VV-ECMO). The VV-ECMO system is not used for PCI support. The right atrium or superior vena cava are typical sites for the inflow cannula, and subclavian or femoral artery for the outflow cannula. Some of the benefits seen with the use of VA-ECMO in CS patients include augmentation in cardiac output, decreasing preload, increasing mean arterial pressure (MAP), and increased oxygenation; however, VA-ECMO may also cause an increase in afterload and myocardial oxygen demand, leading to worsening ischemia and congestion.^53,54 In a study comparing standby (n=180) vs prophylactic (n=389) ECMO in patients undergoing PCI, there was no mortality difference. In the subgroup analysis of patients with LVEF <20% (n=158), procedural complications were higher in the prophylactic group (41% vs 9.4%, P<0.01); however, mortality was higher in the standby group (4.8% vs 18.8%, P<0.05).⁵⁵ Sheu et al⁵⁶ prospectively recruited patients with STEMI and CS, and patients who received IABP plus ECMO support had a survival benefit, with a relative risk reduction of 45.8%. In a retrospective study by Wu et al looking at early coronary revascularization in 35 AMI and CS patients on ECMO, 29% survived to hospital discharge after revascularization.⁵⁷ The authors hypothesized that these patients might not have survived without ECMO support. In a retrospective, single-center study in patients presenting with AMI and CS who were either placed on IABP or on IABP with ECMO, the survival benefit seen was immediate after weaning: IABP 44% vs IABP plus ECMO 81.82%, (P=0.005). At 1-year follow-up, the rate of survival was 24% and 63.64%, respectively (P=0.004).58 All the above studies show feasibility and benefit of ECMO in patients undergoing high-risk PCI, but vascular complications do remain the Achilles’ heel of ECMO. 

Temporary VADs requiring a median sternotomy

The BVS 5000, CentriMag, and Thoratec percutaneous ventricular assist device (pVAD) can be used for left, right, or biventricular support, depending on the patient’s need and hemodynamics. All require surgical expertise for placement. Randomized clinical trial data is lacking for these devices, but their use has been shown to be feasible for temporary support in bridge-to-decision situations. CentriMag is the most commonly implanted temporary continuous-flow VAD and has been shown to have acceptable survival rates.⁵⁹ These devices are not routinely utilized for supporting PCI.

Durable VADs including total artificial heart

The INTERMACS registry analysis of 502 critically ill AMI patients supported with durable VADs shows significant survival benefit, with 93% at 1 month, 77% at 1 year, and 70% at 2 years, and no increase in complications in the risk-adjusted analysis.⁶⁰ 

Right heart support devices

Right ventricular (RV) failure has high mortality, RV failure can lead to decreased LV function, and around 40% of patients with LV failure can have RV failure.^61,62,63 Up to 50% of patients presenting with an inferior MI can have echocardiographic evidence of RV dysfunction.⁶² RV support devices are now available, including the TandemLife ProtekDuo (Figure 8), the Impella RP device, and VA-ECMO. The Impella RP (Figure 9) is a percutaneously inserted right ventricular assist device (RVAD) that can direct blood from the IVC to the pulmonary artery with flow rates up to 4 L/min. The TandemLife ProtekDuo can provide a right atrial to pulmonary artery conduit, thereby bypassing the failing RV. Successful use and implantation in cases of RV infarction have been reported.^64,65 AMI patients implanted with a centrifugal RVAD had the best survival rates (33%) over all the indications for which it was used.66 In the RECOVER-RIGHT⁶⁷ trial, in the subgroup of 12 patients with AMI and RV failure, 30-day survival was 73%, significant improvement was seen in the CI, and a significant decrease was observed in central venous pressure. VA-ECMO can be used for bi-ventricular failure in such cases as well.

Anticoagulation and antiplatelet therapy

Since blood is circulated in an external circuit in all of these devices, which increases the propensity of embolic and thrombotic phenomena, intravenous heparin should be used for anticoagulation. VAD implantation causes consumption of coagulation proteins, activation of the coagulation cascade, platelet activation, and loss of von Willebrand protein.68,69 Along with anticoagulation, most patients undergoing PCI are placed on antiplatelet therapy for added benefit. Bleeding complications are common in LVAD patients, and are a cause of increased mortality and morbidity.² Triple therapy after PCI is generally initiated in such patients, but no data is available in regards to its recommended duration or patient outcomes. 

Conclusion

There are now many options available for mechanical circulatory support in high-risk PCI in various settings. However, except in cases of cardiogenic shock, the use of such devices has been modest at best.^15,70 Mechanical circulatory support devices should be considered for use in patients undergoing high-risk PCI and in those patients with cardiogenic shock and bi-ventricular failure.^6,71 Patient selection is paramount in the use of these devices, as each can be conformed to specific patient and clinical needs. Uncertainty still remains regarding superiority, safety, and long-term outcomes. There are some observational data and meta-analyses that also show use of IABP has been associated with decreased survival.^32,70,72 The use of IABP and ECMO together may be more beneficial than either one used individually, as they can complement each other’s hemodynamic profiles. A heart team approach is recommended in making a sound patient and device selection, and operators should keep in mind that the hemodynamic support can be escalated in a stepwise fashion if needed.^10,71 Data has been lacking in terms of duration of anticoagulation and antiplatelet therapy, and individualized decisions need to be made while recognizing bleeding and thrombotic risks. 

The performance of complex PCI procedures is likely to continue its increase well into the future. Improvement in PCI techniques, and the increased ease and safety of utilization of ventricular assist devices will further allow for percutaneous support in patients undergoing high-risk PCI procedures. The major drawbacks of bleeding complications associated with large-bore sheaths will hopefully continue to decrease as these support devices further evolve.

References

1. Weintraub RM, Aroesty JM, Paulin S, et al. Medically refractory unstable angina pectoris. I. Long-term follow-up of patients undergoing intraaortic balloon counterpulsation and operation. Am J Cardiol. 1979; 43: 877-882.
2. Wayangankar SA, Bangalore S, McCoy LA, et al. 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.
3. Brennan JM, Curtis JP, Dai D, et al. Enhanced mortality risk prediction with a focus on high-risk percutaneous coronary intervention: results from 1,208,137 procedures in the NCDR (National Cardiovascular Data Registry). JACC Cardiovasc Interv. 2013; 6: 790-799.
4. Levine GN, Bates ER, Blankenship JC, et al. 2011 ACCF/AHA/SCAI Guideline for percutaneous coronary intervention: executive summary: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines and the Society for Cardiovascular Angiography and Interventions. Catheter Cardiovasc Interv. 2012; 79: 453-495.
5. O’Gara PT, Kushner FG, Ascheim DD, et al. 2013 ACCF/AHA guideline for the management of ST-elevation myocardial infarction: executive summary: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Circulation. 2013; 127: 529-555.
6. Rihal CS, Naidu SS, Givertz MM, et al. 2015 SCAI/ACC/HFSA/STS clinical expert consensus statement on the use of percutaneous mechanical circulatory support devices in cardiovascular care (endorsed by the American Heart Association, the Cardiological Society of India, and Sociedad Latino Americana de Cardiologia Intervencion; Affirmation of Value by the Canadian Association of Interventional Cardiology-Association Canadienne de Cardiologie d’intervention). J Card Fail. 2015; 21: 499-518.
7. Burkhoff D, Cohen H, Brunckhorst C, O’Neill WW, TandemHeart Investigators G. A randomized multicenter clinical study to evaluate the safety and efficacy of the TandemHeart percutaneous ventricular assist device versus conventional therapy with intraaortic balloon pumping for treatment of cardiogenic shock. Am Heart J. 2006; 152: 469 e1-e8.
8. O’Neill WW, Kleiman NS, Moses J, et al. A prospective, randomized clinical trial of hemodynamic support with Impella 2.5 versus intra-aortic balloon pump in patients undergoing high-risk percutaneous coronary intervention: the PROTECT II study. Circulation. 2012; 126: 1717-1727.
9. Thiele H, Sick P, Boudriot E, et al. Randomized comparison of intra-aortic balloon support with a percutaneous left ventricular assist device in patients with revascularized acute myocardial infarction complicated by cardiogenic shock. Eur Heart J. 2005; 26: 1276-1283.
10. Atkinson TM, Ohman EM, O’Neill WW, Rab T, Cigarroa JE; Interventional Scientific Council of the American College of Cardiology. A practical approach to mechanical circulatory support in patients undergoing percutaneous coronary intervention: an interventional perspective. JACC Cardiovasc Interv. 2016; 9: 871-883.
11. Cohen M, Urban P, Christenson JT, et al. Intra-aortic balloon counterpulsation in US and non-US centres: results of the Benchmark Registry. Eur Heart J. 2003; 24: 1763-1770.
12. Clauss RH, Birtwell WC, Albertal G, et al. Assisted circulation. I. The arterial counterpulsator. J Thorac Cardiovasc Surg. 1961; 41: 447-458.
13. Myat A, McConkey H, Chick L, Baker J, Redwood S. The intra-aortic balloon pump in high-risk percutaneous coronary intervention: is counterpulsation counterproductive? Interventional Cardiology. 2012; 4: 211-234.
14. Khera R, Cram P, Vaughan-Sarrazin M, Horwitz PA, Girotra S. Use of mechanical circulatory support in percutaneous coronary intervention in the United States. Am J Cardiol. 2016; 117: 10-16.
15. Curtis JP, Rathore SS, Wang Y, Chen J, Nallamothu BK, Krumholz HM. Use and effectiveness of intra-aortic balloon pumps among patients undergoing high risk percutaneous coronary intervention: insights from the National Cardiovascular Data Registry. Circ Cardiovasc Qual Outcomes. 2012; 5: 21-30.
16. 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.
17. Hochman JS, Buller CE, Sleeper LA, et al. Cardiogenic shock complicating acute myocardial infarction—etiologies, management and outcome: a report from the SHOCK Trial Registry. J Am Coll Cardiol. 2000;36:1063-1070.
18. Sanborn TA, Sleeper LA, Bates ER, et al. Impact of thrombolysis, intra-aortic balloon pump counterpulsation, and their combination in cardiogenic shock complicating acute myocardial infarction: a report from the SHOCK Trial Registry. SHould we emergently revascularize Occluded Coronaries for cardiogenic shocK? J Am Coll Cardiol. 2000; 36: 1123-1129.
19. Perera D, Stables R, Clayton T, et al. Long-term mortality data from the balloon pump-assisted coronary intervention study (BCIS-1): a randomized, controlled trial of elective balloon counterpulsation during high-risk percutaneous coronary intervention. Circulation. 2013; 127: 207-212.
20. 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.
21. Thiele H, Zeymer U, Neumann FJ, et al. Intra-aortic balloon counterpulsation in acute myocardial infarction complicated by cardiogenic shock (IABP-SHOCK II): final 12 month results of a randomised, open-label trial. Lancet. 2013; 382: 1638-1645.
22. Briguori C, Sarais C, Pagnotta P, et al. Elective versus provisional intra-aortic balloon pumping in high-risk percutaneous transluminal coronary angioplasty. Am Heart J. 2003; 145: 700-707.
23. Mishra S, Chu WW, Torguson R, et al. Role of prophylactic intra-aortic balloon pump in high-risk patients undergoing percutaneous coronary intervention. Am J Cardiol. 2006; 98: 608-612.
24. Bahekar A, Singh M, Singh S, et al. Cardiovascular outcomes using intra-aortic balloon pump in high-risk acute myocardial infarction with or without cardiogenic shock: a meta-analysis. J Cardiovasc Pharmacol Ther. 2012; 17: 44-56.
25. Cassese S, de Waha A, Ndrepepa G, et al. Intra-aortic balloon counterpulsation in patients with acute myocardial infarction without cardiogenic shock. A meta-analysis of randomized trials. Am Heart J. 2012; 164: 58-65 e1.
26. Chen S, Yin Y, Ling Z, Krucoff MW. Short and long term effect of adjunctive intra-aortic balloon pump use for patients undergoing high risk reperfusion therapy: a meta-analysis of 10 international randomised trials. Heart. 2014; 100: 303-310.
27. Sjauw KD, Engstrom AE, Vis MM, et al. A systematic review and meta-analysis of intra-aortic balloon pump therapy in ST-elevation myocardial infarction: should we change the guidelines? Eur Heart J. 2009; 30: 459-468.
28. Kolh P, Windecker S, Alfonso F, et al. 2014 ESC/EACTS Guidelines on myocardial revascularization: the Task Force on Myocardial Revascularization of the European Society of Cardiology (ESC) and the European Association for Cardio-Thoracic Surgery (EACTS). Developed with the special contribution of the European Association of Percutaneous Cardiovascular Interventions (EAPCI). Eur J Cardiothorac Surg. 2014; 46: 517-592.
29. Khera R, Cram P, Lu X, et al. Trends in the use of percutaneous ventricular assist devices: analysis of national inpatient sample data, 2007 through 2012. JAMA Intern Med. 2015; 175: 941-950.
30. Patel NJ, Singh V, Patel SV, et al. Percutaneous Coronary Interventions and Hemodynamic Support in the USA: A 5 Year Experience. J Interv Cardiol. 2015; 28: 563-573.
31. Stretch R, Sauer CM, Yuh DD, Bonde P. National trends in the utilization of short-term mechanical circulatory support: incidence, outcomes, and cost analysis. J Am Coll Cardiol. 2014; 64: 1407-1415.
32. Romeo F, Acconcia MC, Sergi D, et al. Percutaneous assist devices in acute myocardial infarction with cardiogenic shock: Review, meta-analysis. World J Cardiol. 2016; 8: 98-111.
33. Cheng JM, den Uil CA, Hoeks SE, et al. Percutaneous left ventricular assist devices vs. intra-aortic balloon pump counterpulsation for treatment of cardiogenic shock: a meta-analysis of controlled trials. Eur Heart J. 2009; 30: 2102-2108.
34. Reesink KD, Dekker AL, Van Ommen V, et al. Miniature intracardiac assist device provides more effective cardiac unloading and circulatory support during severe left heart failure than intraaortic balloon pumping. Chest. 2004; 126: 896-902.
35. Remmelink M, Sjauw KD, Henriques JP, et al. Effects of left ventricular unloading by Impella recover LP2.5 on coronary hemodynamics. Catheter Cardiovasc Interv. 2007; 70: 532-537.
36. Sjauw KD, Remmelink M, Baan J, Jr., et al. Left ventricular unloading in acute ST-segment elevation myocardial infarction patients is safe and feasible and provides acute and sustained left ventricular recovery. J Am Coll Cardiol. 2008; 51: 1044-1046.
37. Cohen MG, Matthews R, Maini B, et al. Percutaneous left ventricular assist device for high-risk percutaneous coronary interventions: Real-world versus clinical trial experience. Am Heart J. 2015; 170: 872-879.
38. Lauten A, Engstrom AE, Jung C, et al. Percutaneous left-ventricular support with the Impella-2.5-assist device in acute cardiogenic shock: results of the Impella-EUROSHOCK-registry. Circ Heart Fail. 2013; 6: 23-30.
39. Seyfarth M, Sibbing D, Bauer I, et al. A randomized clinical trial to evaluate the safety and efficacy of a percutaneous left ventricular assist device versus intra-aortic balloon pumping for treatment of cardiogenic shock caused by myocardial infarction. J Am Coll Cardiol. 2008; 52: 1584-1588.
40. Engstrom AE, Cocchieri R, Driessen AH, et al. The Impella 2.5 and 5.0 devices for ST-elevation myocardial infarction patients presenting with severe and profound cardiogenic shock: the Academic Medical Center intensive care unit experience. Crit Care Med. 2011; 39: 2072-2079.
41. Goldstein AH, Pacella JJ, Clark RE. Predictable reduction in left ventricular stroke work and oxygen utilization with an implantable centrifugal pump. Ann Thorac Surg. 1994; 58: 1018-1024.
42. Kono S, Nishimura K, Nishina T, et al. Autosynchronized systolic unloading during left ventricular assist with a centrifugal pump. J Thorac Cardiovasc Surg. 2003; 125: 353-360.
43. Aragon J, Lee MS, Kar S, Makkar RR. Percutaneous left ventricular assist device: “TandemHeart” for high-risk coronary intervention. Catheter Cardiovasc Interv. 2005; 65: 346-352.
44. Nascimbene A, Loyalka P, Gregoric ID, Kar B. Percutaneous coronary intervention with the TandemHeart percutaneous left ventricular assist device support: six years of experience and outcomes. Catheter Cardiovasc Interv. 2016 May; 87(6): 1101-1110.
45. Alli OO, Singh IM, Holmes DR, Jr., Pulido JN, Park SJ, Rihal CS. Percutaneous left ventricular assist device with TandemHeart for high-risk percutaneous coronary intervention: the Mayo Clinic experience. Catheter Cardiovasc Interv. 2012; 80: 728-734.
46. Al-Husami W, Yturralde F, Mohanty G, et al. Single-center experience with the TandemHeart percutaneous ventricular assist device to support patients undergoing high-risk percutaneous coronary intervention. J Invasive Cardiol. 2008; 20: 319-322.
47. Gimelli G, Wolff MR. Hemodynamically supported percutaneous coronary revascularization improves left ventricular function in patients with ischemic dilated cardiomyopathy at very high risk for surgery: a single-center experience. J Invasive Cardiol. 2008; 20: 642-646.
48. Giombolini C, Notaristefano S, Santucci S, et al. Percutaneous left ventricular assist device, TandemHeart, for high-risk percutaneous coronary revascularization. A single centre experience. Acute Card Care. 2006; 8: 35-40.
49. Rajdev S, Krishnan P, Irani A, et al. Clinical application of prophylactic percutaneous left ventricular assist device (TandemHeart) in high-risk percutaneous coronary intervention using an arterial preclosure technique: single-center experience. J Invasive Cardiol. 2008; 20: 67-72.
50. Thomas JL, Al-Ameri H, Economides C, et al. Use of a percutaneous left ventricular assist device for high-risk cardiac interventions and cardiogenic shock. J Invasive Cardiol. 2010; 22: 360-364.
51. Vranckx P, Foley DP, de Feijter PJ, Vos J, Smits P, Serruys PW. Clinical introduction of the Tandemheart, a percutaneous left ventricular assist device, for circulatory support during high-risk percutaneous coronary intervention. Int J Cardiovasc Intervent. 2003; 5: 35-39.
52. Vranckx P, Meliga E, De Jaegere PP, Van den Ent M, Regar ES, Serruys PW. The TandemHeart, percutaneous transseptal left ventricular assist device: a safeguard in high-risk percutaneous coronary interventions. The six-year Rotterdam experience. EuroIntervention. 2008; 4: 331-337.
53. Aghili N, Kang S, Kapur NK. The fundamentals of extra-corporeal membrane oxygenation. Minerva Cardioangiol. 2015; 63: 75-85.
54. Kawashima D, Gojo S, Nishimura T, et al. Left ventricular mechanical support with Impella provides more ventricular unloading in heart failure than extracorporeal membrane oxygenation. ASAIO J. 2011; 57: 169-176.
55. Teirstein PS, Vogel RA, Dorros G, et al. Prophylactic versus standby cardiopulmonary support for high risk percutaneous transluminal coronary angioplasty. J Am Coll Cardiol. 1993; 21: 590-596.
56. Sheu JJ, Tsai TH, Lee FY, et al. Early extracorporeal membrane oxygenator-assisted primary percutaneous coronary intervention improved 30-day clinical outcomes in patients with ST-segment elevation myocardial infarction complicated with profound cardiogenic shock. Crit Care Med. 2010; 38: 1810-1817.
57. Wu MY, Tseng YH, Chang YS, Tsai FC, Lin PJ. Using extracorporeal membrane oxygenation to rescue acute myocardial infarction with cardiopulmonary collapse: the impact of early coronary revascularization. Resuscitation. 2013; 84: 940-945.
58. Tsao NW, Shih CM, Yeh JS, et al. Extracorporeal membrane oxygenation-assisted primary percutaneous coronary intervention may improve survival of patients with acute myocardial infarction complicated by profound cardiogenic shock. J Crit Care. 2012; 27: 530 e1-11.
59. Borisenko O, Wylie G, Payne J, et al. Thoratec CentriMag for temporary treatment of refractory cardiogenic shock or severe cardiopulmonary insufficiency: a systematic literature review and meta-analysis of observational studies. ASAIO J. 2014; 60: 487-497.
60. Acharya D, Loyaga-Rendon RY, Pamboukian SV, et al. Ventricular Assist Device in Acute Myocardial Infarction. J Am Coll Cardiol. 2016; 67: 1871-1880.
61. Ghio S, Gavazzi A, Campana C, et al. Independent and additive prognostic value of right ventricular systolic function and pulmonary artery pressure in patients with chronic heart failure. J Am Coll Cardiol. 2001; 37: 183-188.
62. Jacobs AK, Leopold JA, Bates E, et al. Cardiogenic shock caused by right ventricular infarction: a report from the SHOCK registry. J Am Coll Cardiol. 2003; 41: 1273-1279.
63. Kapur NK, Jumean MF. Defining the role for percutaneous mechanical circulatory support devices for medically refractory heart failure. Curr Heart Fail Rep. 2013; 10: 177-184.
64. Atiemo AD, Conte JV, Heldman AW. Resuscitation and recovery from acute right ventricular failure using a percutaneous right ventricular assist device. Catheter Cardiovasc Interv. 2006; 68: 78-82.
65. Prutkin JM, Strote JA, Stout KK. Percutaneous right ventricular assist device as support for cardiogenic shock due to right ventricular infarction. J Invasive Cardiol. 2008; 20: E215-216.
66. Kapur NK, Paruchuri V, Jagannathan A, et al. Mechanical circulatory support for right ventricular failure. JACC Heart Fail. 2013; 1: 127-134.
67. Anderson MB, Goldstein J, Milano C, et al. Benefits of a novel percutaneous ventricular assist device for right heart failure: The prospective RECOVER RIGHT study of the Impella RP device. J Heart Lung Transplant. 2015; 34: 1549-1560.
68. Himmelreich G, Ullmann H, Riess H, et al. Pathophysiologic role of contact activation in bleeding followed by thromboembolic complications after implantation of a ventricular assist device. ASAIO J. 1995; 41: M790-M794.
69. Matsubayashi H, Fastenau DR, McIntyre JA. Changes in platelet activation associated with left ventricular assist system placement. J Heart Lung Transplant. 2000; 19: 462-468.
70. Zeymer U, Bauer T, Hamm C, et al. Use and impact of intra-aortic balloon pump on mortality in patients with acute myocardial infarction complicated by cardiogenic shock: results of the Euro Heart Survey on PCI. EuroIntervention. 2011; 7: 437-441.
71. Myat A, Patel N, Tehrani S, Banning AP, Redwood SR, Bhatt DL. Percutaneous circulatory assist devices for high-risk coronary intervention. JACC Cardiovasc Interv. 2015; 8: 229-244.
72. Barron HV, Every NR, Parsons LS, et al. The use of intra-aortic balloon counterpulsation in patients with cardiogenic shock complicating acute myocardial infarction: data from the National Registry of Myocardial Infarction 2. Am Heart J. 2001; 141: 933-939.