Perforation of the Anterior Mitral Leaflet After Impella LP 5.0 Therapy in Cardiogenic Shock

Outcome of Patients Supported by Large Impella Systems After Re-implantation Due to Continued or Recurrent Need of Temporary Mechanical Circulatory Support

Despite the growing utilization of a large microaxial pump, i. e., Impella 5.0 or 5.5 (Abiomed Inc., Danvers, MA, USA) (Impella 5+) for patients with cardiogenic shock (CS), adverse events including the necessity of re-implantation have not been well discussed. In all 67 patients, in-hospital mortality was 52.2% (n = 35). Explantation of Impella 5+ was performed in 39 patients (58.2%), 22 of whom (32.8%) recovered under Impella 5+, and ten further patients (14.9%) survived after a successful transition to permanent mechanical circulatory support. Embolic events were considerable complications in each access. They occurred in the right arm after the removal of Impella 5+ via a subclavian artery (SA) (n = 3, 9.1%) or in the form of leg ischemia in patients with Impella 5+ via femoral artery (FA) (n = 2, 33.3%). Re-implantation was necessary for 10 patients (14.9%) due to 1) recurrent CS (n = 3), 2) pump thrombosis (n = 5), or 3) pump dislocation (n = 2), all of which were successfully performed via the same access route. In univariate analysis, FA access was a significant risk factor for Impella dysfunction compared to SA access (FA vs. SA, 42.9% vs. 9.8%, p < 0.05, odds ratio 6.88). No statistical difference of overall mortality was observed in patients with Impella 5+ re-implantation (n = 10) compared to patients with primary Impella 5+ support (n = 57) (80.0% (n = 8/10) vs. 47.4% (n = 27/57), p = 0.09). Our results suggested the acceptable clinical outcome of Impella 5+ despite a 15% re-implantation rate. Our observational data may merit further analysis of anticoagulation strategies, including risk stratification for embolic events.

Echocardiographic imaging of temporary percutaneous mechanical circulatory support devices

Cardiogenic shock is a state of end-organ hypoperfusion due to primary cardiac dysfunction and portends a poor prognosis. Shock refractory to inotropic and vasopressor support is often an indication for mechanical circulatory support. When mechanical support device complications or malfunction arise, echocardiography offers rapid assessment of device position and function. Repositioning can be done under echocardiographic guidance. Despite the widespread use of percutaneous mechanical circulatory support, there is a dearth of information regarding echocardiography as it pertains to these devices. In this review, we discuss the utility of echocardiography with percutaneous mechanical circulatory support devices.

Intensive care unit management of percutaneous mechanical circulatory supported patients: the role of imaging

The clinical management of patients on Impella support requires multimodality monitoring and imaging. Upon intensive care unit admission, echocardiography is essential to ensure correct pump positioning/guide repositioning, to monitor acute myocardial infarction/device-related cardiac complications and to evaluate baseline left and right ventricular function. Over time, the echocardiographic assessment of myocardial viability has become an essential target for guiding mechanical circulatory support escalation and long-term strategies. The recognition and grading of any valvular dysfunction and damage in Impella patients are challenging, as the device interferes with the colour Doppler signal, and the loading conditions of the left ventricle are modified by the pump. Valvular disease in such patients is often secondary, and correct identification is pivotal for future therapeutic strategies. The emerging use of newer techniques, including speckle-tracking echocardiography, is of increasing interest in the imaging of critically ill patients.

Left Ventricle Architecture and Valvular Integrity Following Microaxial Mechanical Support: A Two-Year Follow-Up Study

Although the use of microaxilar mechanical circulatory support systems may improve the outcome of patients with cardiogenic shock (CS), little is known about its effect on the long-term structural integrity of left ventricular (LV) valves as well as on the development of LV-architecture. Therefore, we aimed to study the integrity of the LV valves and architecture and function after Impella support. Thus, 84 consecutive patients were monitored over two years having received Impella^TM CP (n = 24) or 2.5 (n = 60) for refractory CS (n = 62) or for high-risk percutaneous coronary interventions (n = 22) followed by optimal medical treatment. Beside a significant increase in LV ejection fraction after two years (p ≤ 0.03 vs. pre-implantation), we observed a statistically significant decrease in LV dilation (p < 0.001) and severity of mitral valve regurgitation (p = 0.007) in the two-year follow-up period, suggesting an improved LV architecture. Neither the duration of support, nor the size of the Impella device or the indication for its use revealed any devastating impact on aortic or mitral valve integrity. These findings indicate that Impella device is a safe means of support of LV-function without detrimental long-term effects on the structural integrity of LV valves regardless of the size of the device or the indication of support.

The Physiologic Basis and Clinical Outcomes of Combined Impella and Veno-Arterial Extracorporeal Membrane Oxygenation Support in Cardiogenic Shock

Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) provides effective hemodynamic support in cardiogenic shock, but in some cases may be complicated by left ventricular (LV) distension and pulmonary edema. The Impella, a catheter-mounted microaxial pump has been used to unload the LV. Recent studies have compared the clinical outcomes of VA-ECMO to the combination of Impella and VA-ECMO. The purpose of this review is threefold: firstly, to discuss the physiological effects of Impella support in addition to VA-ECMO, secondly to review published studies on the outcome of this combined support, and thirdly to provide a practical overview of the approach to combining Impella and VA-ECMO.

Percutaneous Approaches to the Treatment of Mitral Leaflet Perforation and to Residual Regurgitation After Transcatheter Edge-to-Edge Mitral Valve Repair

Mitral valve disease becomes more prevalent as the population ages. As the number of percutaneous mitral valve interventions expands, obscure clinical scenarios may emerge and challenge conventional treatment algorithms. Strategies for dealing with complex repairs build on prior experience in mitral perivalvular leak repair. Cases using nitinol- and expanded polytetrafluoroethylene-based devices are used to treat mitral regurgitation in cases of focal mitral perforations and leaks between previously placed mitral valve edge-to-edge devices. This review discusses risks and benefits of performing such complex mitral repairs and informs clinicians of the strengths of weaknesses of different occluder devices in the mitral position.

A method for maintaining vascular access when Impella exchange is required

A 45-year old male with no prior cardiac history, presented with cardiogenic shock in the setting of an anterolateral ST elevation myocardial infarction. We first placed a 2.5 Impella for hemodynamic support, and proceeded with emergent percutaneous coronary intervention to the proximal LAD. Several hours following percutaneous coronary intervention (PCI), the patient became acutely hypotensive and an echocardiogram revealed the Impella catheter was kinked within the left ventricle. The patient was taken back to the cath lab for Impella adjustment; however, damage to the distal catheter required the Impella be exchanged. As the patient was therapeutically anticoagulated and on dual antiplatelet therapy, we modified the Impella catheter in order to maintain existing vascular access during Impella exchange. This case demonstrates our method for maintaining vascular access during Impella exchange, thereby eliminating the need for a second arterial puncture. © 2017 Wiley Periodicals, Inc.

Maintenance of valvular integrity with Impella left heart support: Results from the multicenter PROTECT II randomized study

BACKGROUND

The Impella 2.5 axial flow pump, which is positioned across the aortic valve, is widely employed for hemodynamic support. The present study compared structural and functional integrity of the left heart valves in patients undergoing Impella vs intra-aortic balloon pump in the randomized PROTECT II trial.

METHODS AND RESULTS

Transthoracic echocardiograms were performed at baseline, 1 and 3 months in 445 patients in the PROTECT II trial. Serial studies were analyzed by an independent echocardiography core laboratory for aortic and mitral valve structure and function, and left ventricular ejection fraction (LVEF). During Impella support there was no appreciable change in the degree of baseline valvular regurgitation. There were no cases of structural derangement of the mitral or aortic valve after use of the Impella device. At 90-day follow-up, there was an average 22% relative increase in LVEF from baseline (27% ± 9 vs. 33% ± 11, P < 0.001).

CONCLUSIONS

The present echocardiographic analysis of the PROTECT II study confirms prior observations regarding the safety of the Impella 2.5 device with respect to mitral and aortic valve function.

Mechanical circulatory support in patients with severe aortic stenosis and left ventricular dysfunction undergoing percutaneous coronary intervention

Management of obstructive coronary artery disease in patients with aortic stenosis and severe left ventricular dysfunction is challenging. Mechanical circulatory support at the time of percutaneous coronary interventions may be necessary in these extreme-risk patients. We present a case in which the TandemHeart was used to support a patient with severe aortic stenosis, severe protected left main and circumflex disease, and severe cardiomyopathy and review the literature on this subject.

Temporary Mechanical Circulatory Support in Cardiac Critical Care: A State of the Art Review and Algorithm for Device Selection

With more than 60 years of continuous development and improvement, a variety of temporary mechanical circulatory support (MCS) devices and implantation strategies exist, each with unique advantages and disadvantages. A thorough understanding of each available device is essential for optimizing patient outcomes in a fiscally responsible manner. In this state of the art review we examine the entire range of commonly available peripheral and centrally cannulated temporary MCS devices, including intra-aortic balloon pumps, the Impella (Abiomed, Danvers, MA) family of microaxial pumps, the TandemHeart (CardiacAssist Inc, Pittsburg, PA) pump and percutaneous cannulas, centrally cannulated centrifugal pumps such as the CentriMag (Thoratec Corp, Pleasanton, CA/St Jude Medical, St Paul, MN/Abbott Laboratories, Abbott Park, IL) and Rotaflow (Maquet Holding BV & Co KG, Rastatt Germany), and extracorporeal membrane oxygenation. Several factors need detailed consideration when contemplating MCS in any given patient, mandating a balanced, algorithmic approach for these sick patients. In this review we describe our approach to MCS, and emphasize the need for multidisciplinary input to consider patient-related, logistical, and institutional factors. Evidence is summarized and referenced where available, but because of the lack of high-quality evidence, current best practice is described. Future directions for investigation are discussed, which will better define patient and device selection, and optimize MCS-specific patient care protocols.