Patient History at Presentation
A 59-year-old man was referred to California Pacific Medical Center for treatment of decompensated heart failure. The patient had a past history of ischemic cardiomyopathy, implantable cardioverter defibrillator (ICD) implantation, five-vessel coronary artery bypass graft (CABG) surgery in 1997, insulin-dependent diabetes mellitus, tobacco dependence, and chronic atrial fibrillation on anticoagulation therapy. The patient’s ejection fraction was <15% and he was on home intravenous dobutamine therapy. A coronary angiography, performed at the referring hospital, revealed a 90% proximal stenosis of the left anterior descending (LAD) coronary artery and total occlusion of the mid LAD, a 50% proximal stenosis of a large arborizing first diagonal artery, which supplied most of the anterolateral wall, and collateralized a 100% proximally occluded circumflex artery. The right coronary artery (RCA) was occluded proximally (Figure 1). None of the bypass grafts were patent. A linear opacity suspicious for a dissection of unknown mechanism was evident in the shaft of left main coronary artery (LMCA) (Figure 2).

Surgical consultation to assess the patient’s suitability for repeat CABG was obtained. However, due to his significant co-morbidities and suboptimal distal targets, the patient was turned down for re-do surgery. The patient declined evaluation for implantation of a left ventricular assist device as destination therapy.

The patient was considered to be at very high risk for possible abrupt left main closure and death, given his diffuse coronary artery disease (CAD), possible LMCA dissection, and severely depressed left ventricular function. He was advised to undergo repeat catheterization with intravascular ultrasound (IVUS) guidance to confirm the presence of the dissection and develop a percutaneous coronary intervention (PCI) strategy. Because of the potential risk of profound ischemia from IVUS catheter obstruction or extension of dissection during imaging, we decided to place an Impella Recover LP 2.5 left ventricular assist device (Abiomed, Inc., Danvers, MA) for intra-procedural hemodynamic support.

High-Risk PCI: Procedure Details
The Impella Recover LP 2.5 (Figure 3) is a percutaneous micro-axial left ventricular assist device that utilizes the Archimedes principle to draw blood from the left ventricle through an inflow cannula and deliver non-pulsatile blood flow up to 2.5 L/min into the ascending aorta through an outflow port. The maximum diameter of the device is 4 mm [13 French (Fr)] at the pump body that is positioned in the ascending aorta. The axial flow pump is powered by an encapsulated extracorporeal electric motor connected to an external control console.

A 13 Fr sheath was placed in the right femoral artery using a pre-close technique with two orthogonally placed 6 Fr Perclose closure devices (Abbott Vascular, Redwood City, CA). Intra-arterial heparin was administered to maintain an activated clotting time >250 seconds. A 0.018-inch exchange length guidewire (Boston Scientific, Natick, MA) was advanced into the left ventricle through a 6 Fr JR 4 diagnostic catheter (Boston Scientific). The JR 4 diagnostic catheter was removed and the Impella inflow cannula was advanced across the aortic valve and positioned within the left ventricle with fluoroscopy guidance and pressure monitoring (Figure 4). The assist device was activated and a maximum flow of 2.5 L/min was established.

IVUS imaging confirmed a mid shaft dissection of the LMCA and high-risk (unprotected) PCI was performed with Impella support maintained at 2.5L/min. A 3.0 mm x 16 mm drug-eluting stent (Taxus Liberte, Boston Scientific) was positioned in the proximal LAD. This stent was crushed by a 4 mm x 15 mm balloon (Quantum Maverick RE, Boston Scientific) inflated to 14 atmospheres for 20 seconds, followed by deployment of a 4.0 mm x 24 mm drug-eluting Taxus Liberte stent, positioned from the proximal LMCA into the mid diagonal coronary artery. The bifurcation stents were post-dilated using a kissing balloon technique, performed with 3.0 mm and 4.0 mm balloons to the LAD and LMCA/diagonal stents, respectively (Figure 5). The patient’s systolic blood pressure fell transiently from his baseline of 85 to 60 mmHg at the time of LMCA stent deployment and balloon dilatations; however, however, it quickly recovered and remained stable during the course of the procedure

The patient was weaned from Impella circulatory support over 40 minutes post-PCI. The 13 Fr sheath was removed and hemostasis was achieved using the pre-close technique. Post procedure, the patient had an uneventful recovery with no elevation of myocardial enzymes, or evidence of ischemia or decline in cardiac output. The patient was discharged 48 hours after the high-risk PCI with encouragement to quit smoking and to begin a supervised exercise program.

Discussion
The patient underwent successful percutaneous intervention of his LMCA, diagonal artery and LAD with implantation of drug-eluting stents to LMCA/diagonal arteries (4.0 x 24 mm) and LAD (3.0 x 16 mm) using a “crush” technique. The left main was his only remaining vessel, as his RCA and previous bypass grafts all were occluded. Despite the patient's severe left ventricular dysfunction, the Impella percutaneous left ventricular device maintained hemodynamic stability during the procedure. A TandemHeart device (CardiacAssist, Inc., Pittsburgh, PA) was also considered, but we believed that the lower risk and relative simplicity of the Impella device was more appropriate for this patient.

This case demonstrated the utility of the Impella 2.5 in supporting high risk PCI of the only remaining vessel in a patient with severe ischemic cardiomyopathy.

Dr. Beyer can be contacted at BeyerA@sutterhealth.org.

Note: This article is a corrected version and differs from the original print version.