Cath-mounted heart pumps for short-term use

September 12, 2018 0 By S Harachand

Impella heart pump is a percutaneous ventricular assist device to temporarily aid the flow of blood while the patient is undergoing an elective or urgent high-risk percutaneous cardiac intervention (PCI) procedure. This catheter mounted micro-axial pump works on the principle of Archimedes’ Screw. With each rotation, the screw system scoops a certain volume of blood from the left ventricle and ejects it into ascending aorta. A motor rotates the assembly at high speed leading up to 5 litres of cardiac output, depending on the type of Impella device used. The device can be removed soon after the procedure. However, it can be left in place if required even after the procedure until the functioning of the heart stabilises.

Currently, the device is available as Impella 2.5, Impella LP 5.0, Impella LD, Impella CP and Impella RP. All the versions, except Impella RP, received pre-market approval by the USFDA in 2016 for short-term use (<= 4 days for 2.5 and CP, and <=6 days for 5.0 and LD) in ongoing cardiogenic
shock that occurs immediately (<48 hours) following acute myocardial infarction or open heart surgery as a result of isolated left ventricular failure that is not responsive to optimal medical management and conventional treatment measures. The approval was based on trials ISAR-SHOCK, RECOVER I, and PROTECT-II.

The indications were expanded in February 2018 to include cardiomyopathy leading to cardiogenic shock. In addition, the expanded approval included the short-term use (<6 hours) of Impella 2.5 and Impella CP during urgent or elective percutaneous coronary interventions in patients with severe coronary artery disease, complex coronary anatomy, and multiple comorbidities with or without reduced left ventricular systolic function, supported by the data from PROTECT I and PROTECT II trials.

The Indian drug regulator granted approval to Impella 2.5, Impella 5.0 and Impella CP in July 2018 for use during high-risk percutaneous coronary intervention, cardiogenic shock and other reduced-left-ventricular-function conditions. The approval gains importance at a time when India is witnessing an alarming increase in  heart disease cases and a proportionate increase in the number of deaths due to cardiac ailments.

“Indian hospitals are commonly witnessing patients
with severe coronary artery disease and multiple
co-morbidities. While coronary intervention in such
patients is high risk, these patients have high mortality if
the disease is left untreated,” says Dr Anoop Agrawal, Consultant Interventionist, CARE Hospitals, Banjara Hills, Hyderabad.

Many such patients with complex diseases may benefit from PCI using Impella heart pump. India has witnessed a 34% rise in death from cardiovascular causes in the past 26 years, he added.

Impella is getting increasingly accepted the world over. Abiomed Inc, which makes the device, registered a jump of 42% in its worldwide revenues from Impella heart pump in the fourth quarter of the financial year 2018 compared to the previous year.

In India, a protected PCI procedure, including atherectomy with Impella 2.5 support, was performed in July at Fortis Escorts Heart Institute, New Delhi, probably for the first time in the country.

According to Dr Agrawal, Impella’s enrollment is currently limited to centres in Delhi and Jaipur. Apart from lack of expertise and limited availability, early adoption of the device could be restricted due to its high cost.

“Impella, as it stands currently, is cost-prohibitive for
the majority of the Indian population,” Dr Agrawal says. “Impella increases the overall cost of a PCI multi-fold,
which, in a cost-sensitive Indian healthcare market, can certainly be a point of contention, particularly since Impella use in high-risk PCI has not conclusively shown to improve mortality.”

There is a learning curve associated with Impella implantation and its troubleshooting, particularly among technicians and nurses.

Impella heart pump is the only percutaneous ventricular assist device approved for a variety of cardiovascular scenarios. This breakthrough device can be a powerful addition to any cardiac catheterization laboratory armamentarium. Whether it will find its place in Indian healthcare market will largely depend on cost-effectivity as well as local availability of device and clinical expertise, Dr Agrawal pointed out.

The feasibility of Impella for use in ischemia-related cardiac arrest, especially when cardiac intervention is needed, is well established. But further clinical studies are required to prove its routine use in cardiopulmonary resuscitation (CPR) situations.