Impella 2.5 for haemodynamic support during high-risk percutaneous coronary interventions

Level of innovation

Two specialist commentators indicated that, when it was introduced, the Impella 2.5 was a marked improvement on existing technology with greater cardiac output than intra‑aortic balloon pumps (IABPs) and the ability to provide a stable output independent of the underlying heart rhythm or function. However, the Impella pump has been available for a number of years and is now not considered to be novel. They considered that the Impella 2.5 has been superseded by the Impella CP (Cardiac Power), which increases cardiac output by up to 3.5 litres per minute, requires slightly larger‑bore vascular access and is likely to be of greater benefit to patients. Two specialists noted that several similar devices are currently available but did not think that the Impella 2.5 had been superseded.

Potential patient impact

The specialist commentators each identified subgroups of patients who may benefit from Impella 2.5. Five specialist commentators considered Impella 2.5 to be of more benefit in patients who are in extreme haemodynamic states, for example cardiogenic shock following myocardial infarction. One added that Impella 2.5 could be used as a 'bridge' to more invasive methods in these patients.

Other subgroups identified by specialist commentators as potentially benefitting from Impella 2.5 included:

Potential system impact

Four specialist commentators noted that the use of Impella 2.5 would have cost implications because of the high device cost. One added that the device would also add complexity to treatment.

One commentator suggested that although Impella 2.5 may have a dramatic and potentially life‑saving impact for selected patients for whom it is suitable, this is unlikely to translate to system‑wide cost savings.

However, 2 specialist commentators suggested that it may reduce costs in the long term if it prevents patients from progressing to more complex forms of haemodynamic support.

Another specialist considered that, for particular high‑risk cohorts (such as patients who need rotational atherectomy or complex chronic total occlusion angioplasty), using Impella 2.5 may allow PCI procedures that would otherwise not be possible. This would have a positive system impact because Impella would allow for revascularisation procedures in these patients, and so would lead to fewer future hospital admissions.

One specialist highlighted the fact that using Impella 2.5 allowed cardiogenic shock patients to be managed in a coronary care unit (CCU) rather than cardiac ICU (cICU). This was likely to have a major system impact because of the significant reduction in terms of cost and bed management. However, the specialist noted that these cost savings would not be seen in centres that do not use surgical LVADs; these centres would see an increase in costs, because patients having Impella 2.5 are more likely to be managed medically in the early period following PCI. Similarly, extracorporeal membrane oxygenation (ECMO) can lead to cancellation of elective cardiac surgical cases because so many cICU staff are needed; 2 commentators felt that reducing the need for ECMO would avoid these implications.

Three specialist commentators noted the need for training to use Impella 2.5. One considered there to be a clear learning curve associated with using Impella 2.5, not only for interventional cardiologists but for the intensive care and coronary care units and staff managing the patients once they leave the cardiac catheter laboratory.

General comments

Two specialist commentators suggested that the broad patient inclusion criteria in the PROTECT II trial may account for the lack of mortality benefit or differences in outcomes observed. One noted that it may not be feasible to carry out a randomised controlled trial for patients having high‑risk PCI as this is a select group and the risks may be too high.

Two commentators noted the lack of definitive clinical evidence and saw this, along with the cost of the technology, as a barrier to the adoption of Impella 2.5 across the NHS.