Non ST-Elevation Myocardial Infarction Patient with Severely Depressed Ejection Fraction Supported by Impella® 2.5

Introduction Patients with compromised left ventricular (LV) function benefit from LV unloading during high-risk percutaneous coronary intervention (PCI). The Impella 2.5 (Impella, Figure 1) is a minimally invasive, catheter-based cardiac assist device designed to directly unload the LV and thereby reduce myocardial work and oxygen consumption. The device augments cardiac output and improves coronary and systemic end-organ perfusion. We report on a patient with severe LV impairment who underwent a complex PCI while supported with the Impella, and had an uneventful recovery and hospital discharge. Case presentation An 82-year-old female with history of inferior lateral myocardial infarction in 2001 was admitted to a referring hospital with non-ST elevation myocardial infarction complicated by acute decompensated systolic heart failure. An echocardiogram on admission estimated her left ventricular ejection fraction at 10%. Despite aggressive medical therapy, her heart failure remained refractory, and she continued to have angina at rest and non-sustained ventricular tachycardia. She was transferred to the Heart Center at Lankenau Hospital for cardiac catheterization, which identified complex, multi-level three-vessel coronary artery disease (CAD). The left anterior descending (LAD) coronary artery had 90% ostial and 80% mid vessel stenoses (Figure 2). The left circumflex (LCX) coronary artery had an 80% ostial stenosis and total occlusion distally. The ramus artery showed 100% occlusion at its origin. The right coronary artery (RCA) showed a 90% ostial stenosis. The patient was evaluated by cardiothoracic surgery for consideration of coronary artery bypass grafting (CABG); however, due to her complex co-morbidities, lack of well-defined distal vessels for bypass graft placement, advanced age, and low cardiac output/index, a surgical treatment option was not made available. Interventional procedure After discussion with the patient and her family, the patient consented to a high-risk complex multi-vessel PCI with left ventricular support with the Impella. A 2-dimensional echocardiogram was performed to rule out significant aortic valvular disease and the presence of any LV thrombus, which was negative. A 13 Fr sheath was placed in the left common femoral artery. Heparin and a glycoprotein IIb/IIIa inhibitor were used for anticoagulation to achieve an activated clotting time of at least 250 seconds. A multipurpose guiding catheter (6 Fr, Cordis Corporation, Miami, FL) was used to facilitate placement of a 0.035” J-shaped guidewire (180 cm long) across the aortic valve. The J guidewire was then exchanged out for a 0.018” stiff guidewire (180 cm long). An Impella 2.5 catheter was advanced over the 0.018” guidewire and the inflow port was centrally positioned in the LV (Figure 3). Having confirmed appropriate positioning of the inflow and outflow ports, Impella flow rate was gradually increased to achieve a device output into the ascending aorta of 2.5 liter/minute. An 8 Fr XB 3 guide catheter (Cordis) was then advanced from the right femoral artery to engage the left coronary artery. A 3mm x 24 mm Taxus (Boston Scientific Corporation, Natick, MA) drug-eluting stent (DES) was deployed in the mid LAD lesion. Two 3mm x 12mm Taxus DES were positioned at the LAD and LCX ostial lesions, respectively, and deployed utilizing a kissing stent technique (Figure 4). The lesion within the RCA ostium was dilated with balloon angioplasty. The final angiographic result was excellent for all treated coronary artery lesions (Figure 5). Impella pump performance parameters were gradually reduced during a weaning interval. The catheter was removed in the catheterization laboratory when patient hemodynamics had stabilized and circulatory support was no longer indicated. Hemostasis at the left femoral access site was quickly established, aided by the use of a pre-close technique in which two Perclose closure devices (Abbott Vascular, Redwood City, CA) were placed prior to Impella catheter insertion. The patient remained hemodynamically stable during the PCI procedure and without any significant arrhythmia during the interval of left ventricular support with the Impella 2.5. Post procedure, patient cardiac status continued to improve with optimal medical therapy. The patient was discharged one week after an uneventful recovery, free of angina and in stable condition. Discussion This case exemplifies the utility of an easy-to-use left ventricular assist device, such as the Impella 2.5, to facilitate the safe conduct of a high-risk PCI procedure in any patient categorized as extremely high surgical risk for CABG. The PROTECT I study and recently published Europella registry demonstrated that the Impella 2.5 system is safe and feasible for use during high-risk PCI. These studies demonstrated that the device was easy to use, provided excellent hemodynamic support and was associated with a low rate of adverse events compared to other devices, such as an intra-aortic balloon pump (IABP).^1-2 The ISAR-SHOCK randomized trial showed that the Impella 2.5 provided better hemodynamic support than an IABP in patients presenting with acute myocardial infarction cardiogenic shock.³ The MACH 2 trial results, presented at the American College of Cardiology Scientific Session in 2007, also showed significantly higher improvement in left ventricular ejection fraction at 3 days and 120 days in patients supported with the Impella versus patients receiving standard of care treatment (p 4 The three-year follow-up results for MACH 2, presented at the Transcatheter Cardiovascular Therapeutics (TCT) meeting in 2009, also showed significantly improved ejection fraction in the Impella patients, surpassing standard of care patients, with the ultimate ejection fraction increasing from 28% to 51%. In this case, coronary revascularization was considered not feasible without hemodynamic support. The Impella 2.5 is designed to provide critical hemodynamic support and ventricular unloading, and facilitates myocardial recovery post PCI. The authors can be contacted via Dr. Amid Khan at aarkhan@aol.com. Disclosure: Dr. Khan, Dr. Gnall and Dr. Shapiro report no conflict of interest regarding the content herein. References 1. Dixon SR, Henrique JP, Mauri L, et al. A prospective feasibility trial investigating the use of the Impella 2.5 system in patients undergoing high-risk percutaneous coronary intervention (The PROTECT I Trial). JACC Cardiovasc Interv 2009 Feb; 2(2): 91–96. 2. Sjauw KD, Konorza T, Erbel R, et al. Supported high-risk percutaneous coronary intervention with the Impella 2.5 device: The Europella registry. J Am Coll Cardiol 2009 Dec 15;54(25):2430–2434. 3. 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 Nov 4;52(19):1584–1588. 4. Henriques J. Preliminary experience of the MACH 2 trial: Safety and feasibility of left ventricular support with the Impella Recover LP2.5 device in patients with acute ST-segment elevation myocardial infarction. Paper presented at: American College of Cardiology’s (ACC) 56th Annual Scientific Sessions; March 24–27, 2007; New Orleans, La.

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