Clinical experience with the percutaneous hemopump during high-risk coronary angioplasty

Percutaneous Left Ventricular Assist Devices

Percutaneous left ventricular assist devices (P-LVADs) can be life saving and may permit the stabilization of a patient in cardiovascular collapse who would otherwise face imminent demise. For specific patients and clinical indications, or where a greater degree of hemodynamic support is required, numerous studies have demonstrated the feasibility and safety of the newer generation P-LVADs. The potential applications for P-LVADs have continued to expand, now including diverse uses such as support for cardiogenic shock, bridge to and following cardiac surgery, and more novel applications such as complex electrophysiologic mapping and ablation studies of unstable ventricular rhythms.

[High-risk left main coronary stenting supported by percutaneous Impella Recover LP 2.5 assist device]

Percutaneous coronary interventions (PCI) of complex coronary lesions in patients with severely depressed left ventricular (LV) function may increasingly constitute an alternative to surgical revascularization. The availability of hemodynamic support devices offers a promising option to reduce PCI-related complications in such high-risk procedures. We report the case of a successful distal left main coronary artery T-stenting supported by the Impella Recover LP 2.5 assist device in a patient with severe LV dysfunction.

Small pumps for ventricular assistance: progress in mechanical circulatory support

Compared with earlier models, current pumps are much smaller, simpler, and more efficient, offering long-term or even permanent support. They fit a wider size range of patients and are less invasive to implant. Because they have few moving parts, they are less susceptible to infection and failure. Additionally, they offer much greater patient comfort, allowing a relatively normal lifestyle. This article focuses on the current state of continuous-flow pumps for both temporary and long-term use in treating acute and chronic heart failure.

Percutaneous Left Ventricular Support Devices

Patients undergoing percutaneous coronary intervention (PCI) who have severely compromised left ventricular systolic function and complex coronary lesions including multivessel disease, left main disease, or bypass graft disease are at higher risk of adverse outcomes from hemodynamic collapse. The TandemHeart percutaneous left ventricular assist device and the Impella Recover LP 2.5 System may provide rapid circulatory support in high-risk PCI patients and in those who have cardiogenic shock. Identification of patients who are at high risk for severe hemodynamic compromise and most likely to benefit from mechanical circulatory support is crucial to derive the most benefit from this therapy. Multicenter randomized clinical trials are needed to clearly define the role of these two devices in providing circulatory support in a variety of clinical settings.

Transradial unprotected left main coronary stenting supported by percutaneous Impella® Recover LP 2.5 assist device

Percutaneous coronary intervention (PCI) has been increasingly applied to patients with severely depressed left ventricular function and complex coronary lesions. The availability of hemodynamic support devices offers a promising option to reduce PCI-related complications in high-risk procedures. We report the case of a 79-year-old man who suffered from unstable angina. The coronary angiogram revealed multivessel disease including a significant distal left main (LM) stenosis. Additionally, the patient had a history of chronic lymphatic leukemia with immune hemolysis. Therefore, the patient was considered to be at exceptionally high mortality risk in case of cardiac surgery. We decided to perform a percutaneous revascularization of the LM supported by the Impella Recover LP 2.5 assist device. This case report discusses the principles of indications, technique and complications of this new addition to interventional cardiology.

High-risk percutaneous coronary intervention using the intracardiac microaxial pump ‘Impella Recover’

Patients with multivessel coronary artery disease and severe left ventricular dysfunction are considered to be at high risk for percutaneous coronary intervention, and often are poor surgical candidates because of severe comorbidity. We report a case of high-risk percutaneous coronary intervention in a 67-year-old man with a severe left ventricular dysfunction and three-vessel coronary artery disease using a novel left ventricular assist device.

Left ventricular unloading and concomitant total cardiac output increase by the use of percutaneous impella recover LP 2.5 assist device during high-risk coronary intervention

A number of techniques have been proposed for circulatory support during high-risk percutaneous coronary interventions (PCI), but no single approach has achieved wide acceptance so far. We report on a patient with severe left ventricular (LV) impairment who underwent a PCI with the use of a new left ventricular assist device, the Impella Recover LP 2.5 system. The effects on global cardiac output were determined by thermodilution (TD) and LV pressure-volume loops obtained by conductance catheter. The activation of the pump resulted in a rapid and sustained unloading effect of the LV. At the same time, the continuous expulsion of blood into ascending aorta throughout the cardiac cycle produced by the pump resulted in an increase of systemic overall CO, measured by the TD technique, of 1.43 L/min. The procedure was uncomplicated and the patient remained uneventful at follow-up. Our single experience gives new input for future trials to assess the effect of the Impella Recover LP 2.5 assist device on outcome in this subset of patients.

Successful high-risk coronary angioplasty in a patient with cardiogenic shock under circulatory assist with a 16F axial flow pump

We report the case of a 75-year-old patient who suffered from subacute myocardial infarction and severely impaired left ventricular ejection fraction (EF: 17%). Using a novel 16F left ventricular assist device we performed an angioplasty of the right coronary artery, and of the left anterior descending artery. As a result of the circulatory support the patient recovered from cardiogenic shock within 8 hr. At a pump speed of 45,000 rpm the axial flow pump generated flow rates up to 3.3 l/min. The 16F pump cannula was removed using local compression. The EF was 51% at 30-day follow-up examination.

Percutaneous left ventricular assist device: “TandemHeart” for high-risk coronary intervention

Patients undergoing percutaneous coronary intervention (PCI) with severely compromised left ventricular systolic function and complex coronary lesions, including multivessel disease, left main disease, or bypass graft disease, are at higher risk of adverse outcomes from hemodynamic collapse. The TandemHeart percutaneous ventricular assist device may provide circulatory support during high-risk PCI. We implanted the TandemHeart device in eight patients who underwent high-risk PCI. The patients were considered to be at exceptionally high risk for decompensation due to procedural complexity combined with underlying LV dysfunction. The mean ejection fraction was 30% +/- 9% and five patients were turned down for surgical revascularization. Seven patients underwent multivessel PCI, including three patients who underwent unprotected left main coronary artery PCI. There was 100% procedural success. The TandemHeart was removed immediately post-PCI with no groin complications. Six patients are event- and symptom-free at 189 +/- 130 days; one patient died 10 days post-PCI after lower extremity bypass surgery and another developed acute renal failure postprocedure, requiring hemodialysis. Our initial clinical experience with the TandemHeart ventricular assist device demonstrates that hemodynamic support can be rapidly achieved percutaneously during high-risk PCI, with excellent procedural success in highly complex and critically ill patients.

High-risk left main coronary stenting supported by percutaneous left ventricular assist device

Percutaneous left ventricular assist devices could nowadays offer a valid support to percutaneous coronary interventions even in very high risk patients. This case illustrates a successful distal left main coronary artery V-stenting supported by the Tandem Heart in a patient with severe left ventricular dysfunction, severe aortic stenosis, and refractory myocardial ischemia.

Clinical introduction of the Tandemheart, a percutaneous left ventricular assist device, for circulatory support during high-risk percutaneous coronary intervention

BACKGROUND

In patients with poor left ventricular function and high-risk coronary lesions, prolonged ischemia during percutaneous coronary intervention (PCI) may have major hemodynamic consequences. The Tandemheart is a percutaneous left ventricular assist device intended for short-term circulatory support.

METHODS AND RESULTS

The Tandem-heart incorporates 9-17 F. arterial cannulae and a unique 21 F. transseptal cannula and centrifugal bloodpump. Operating at 7500 rpm, the pump withdraws oxygenated blood from the left atrium and delivers up to 4 liters/min to the arterial circulation. As of May 2001, the Tandem-heart was electively employed in three male patients (ages 52, 54 and 56) scheduled for high-risk PCI. The mean time to initial circulatory support was less than 30 minutes. Systemic hemodynamics significantly improved prior to PCI in two patients. Pump flow after one hour ranged from 2.43 to 3.8 liters/min (mean 3.17 liters/min) and duration of support from 23 to 49 hours (mean 33 hours). Procedural success was 100%, with no significant hemolysis or bleeding. Successful weaning was completed in all patients, who have remained free of major cardiac events up to seven months post-PCI.

CONCLUSIONS

In this first clinical experience of elective use of Tandem-heart for circulatory support during high-risk PCI, the device was easily inserted and preserved hemodynamic stability, regardless of the intrinsic cardiac function, creating optimism for more widespread use for this and other indications.

[Reperfusion therapy and mechanical circulatory support in patients in cardiogenic shock]

Cardiogenic shock is a state of inadequate tissue perfusion due to cardiac dysfunction, which is most commonly caused by acute myocardial infarction. The pathophysiology of cardiogenic shock is characterized by a downward spiral: ischemia causes myocardial dysfunction, which, in turn, augments the ischemic damage and the energetical imbalance. With conservative therapy, mortality rates for patients with cardiogenic shock are frustratingly high reaching more than 80%. Additional thrombolytic therapy has not been shown to significantly improve survival in such patients. Emergency cardiac catheterization and coronary angioplasty, however, seem to improve the outcome in shock-patients, which most probably is due to rapid and complete revascularization generally reached by angioplasty. In addition to interventional therapy with rapid coronary revascularization, the use of mechanical circulatory support may interrupt the vicious cycle in cardiogenic shock by stabilizing hemodynamics and the metabolic situation. Different cardiac assist devices are available for cardiologists and cardiac surgeons: 1. intraaortic balloon counterpulsation (IABP), 2. implantable turbine-pump (Hemopump), 3. percutaneous cardiopulmonary bypass support (CPS), 4. right heart, left heart, or biventricular assist devices placed by thoracotomy, and 5. intra- and extrathoracic total artificial hearts. Since percutaneous application is possible with IABP, Hemopump and CPS, these devices are currently used in interventional cardiology. The basic goals of the less invasive intraaortic balloon counterpulsation (IABP; Figure 1) are to stabilize circulatory collapse, to increase coronary perfusion and myocardial oxygen supply, and to decrease left ventricular workload and myocardial oxygen demand (Figure 2). Since the advent of percutaneous placement, IABP has been used by an increasing number of institutions (Figure 3). In addition to cardiogenic shock, the system may be of use in a variety of other indications in the catheterization laboratory and intensive care unit, including weaning from percutaneous cardiopulmonary bypass, in ischaemic left ventricular failure, in unstable angina, in high risk PTCA, and in prophylactic support in patients with myocardial infarction and successful revascularization. Animal experimental data showed that IABP may improve success of thrombolysis and recent clinical data suggest that survival is enhanced and transfer for revascularization is facilitated when patients with myocardial infarction and cardiogenic shock undergo thrombolysis and IABP rather than thrombolysis alone. A lot of studies had demonstrated before, that combined use of counterpulsation and revascularization therapy (i.e. coronary bypass surgery or angioplasty) may improve prognosis in patients with myocardial infarction complicated by cardiogenic shock (Table 1). In such patients, early treatment with IABP is most important: Multivariate analysis identified early IABP-support with a duration of shock to IABP-treatment of > or = 4 hours as an independent predictor of a positive short-term outcome. In shock-patients with postinfarction ventricular septal defect, IABP provides a marked hemodynamic improvement, and a significant decrease in shunt-flow (Figure 5). However, despite initial stabilization with IABP, such patients need immediate surgical repair of the septal defect to avoid hemodynamic deterioration. The rate of complications related to percutaneous IABP was significantly attenuated by employing catheters of reduced size. Using 9.5-F catheters, a long duration of counterpulsation emerged as the most significant factor associated with complications. In our hospital, those patients with 9.5-F catheters in whom counterpulsation did not exceed 48 hours had a low complication rate of 3.9%. The Hemopump is a catheter-mounted transvalvular left ventricular assist device intended for surgical placement via the femoral artery (Figures 6 and 7). (ABSTRACT TRUNCATED)