Utilizing Percutaneous Ventricular Assist Devices in Acute Myocardial Infarction Complicated by Cardiogenic Shock

Percutaneous ventricular assist devices are increasingly being used in patients with acute myocardial infarction and cardiogenic shock. This video demonstrates best practices for insertion of the impella catheter. Utilization of best practices for femoral arterial access and insertion of percutaneous ventricular assist devices is extremely important to reduce the risk of vascular complications in patients with cardiogenic shock.

Begin by using a micropuncture needle to obtain common femoral access over the lower half femoral head under fluoroscopic and ultrasound guidance. To confirm an appropriate arteriotomy location, position the micropuncture sheath and acquire an angiogram of the femoral artery. Insert a six French sheath into the femoral artery, and a pigtail catheter into the inferior portion of the abdominal aorta.

To ensure the absence of peripheral artery disease, obtain an angiogram of the iliofemoral system. Using 8, 10, and 12 French dilators, serially dilate the arteriotomy site over a stiff 0.035 inch wire, before inserting the 14 French peel away sheath under fluoroscopic guidance. Administer an approximately 100 unit per kilogram heparin bolus for an ACT goal of 250 to 300 seconds and flush the sheath.

Use a 0.035 inch J tipped wire to position the pigtail catheter within the left ventricle, then remove the J wire to check the left ventricular end-diastolic pressure. Shape the tip of the exchange length 0.018 inch wire included in the kit, and insert the wire into the left ventricle so that it forms a stable curve at the left ventricular apex. Then, use a preassembled loading red lumen to replace the catheter with an axial flow Archimedes screw pump at a 45 degree angle of insertion.

Gently pull on the label while holding the catheter to remove the loading red lumen and advance the device in small increments into the left ventricle over the 0.018 inch wire. Position the pump in the left ventricle with the inlet four centimeters below the aortic valve, taking care of that the pump is free from the mitral chordae and remove the 0.018 inch wire to allow the pump to be started. Remove excess slack so that the pump rests against the lesser curvature of the aorta, and monitor the console to make sure that the motor current is pulsatile and that the aortic wave form is displayed.

If a ventricular wave form is displayed, the pump may need to be retracted. If the device needs to be left inside tube, you replace the peel away sheath with the repositioning sheath preloaded on the device, and check the device position by fluoroscopy and the wave forms on the console. If the flow is obstructed, place of reperfusion sheath prior to transferring the patient to the critical care unit, then apply sterile dressing and have the patient monitored by personnel trained in the use of the device.

Immediately upon arrival to the cardiac intensive care unit use bedside transthoracic echocardiography in the parasternal long axis view to confirm that the inlet of the device is positioned three to four centimeters from the aortic valve, and note the position of the device in relation to the mitral valve. If the device needs to be repositioned, turn down the device to P-2 and unscrew the locking mechanism on the sterile cover to allow the device to be advanced or retracted. Then lock the device in the new position, document the position, and increase the device to the desired level of support.

Early diagnosis of cardiogenic shock, early insertion of PVAD, and a protocolized and multidisciplinary approach to cardiogenic shock has been shown to improve outcomes in observational data. Vascular complications and limb ischemia due to PVAD is a real concern in patients with cardiogenic shock because it can lead to increased morbidity and mortality. Therefore, it's imperative for the implanting physician to follow best practices for vascular access and insertion of PVAD in order to minimize complications and improve clinical outcomes.

Additionally, it is important to assess for limb ischemia in patients with PVAD and ensure reperfusion to the ischemic limb. It's important to diagnose cardiogenic shock early and follow a protocol-based approach to treat it. Additionally, operators should ensure a safe vascular access with utilization of ultrasound and fluoroscopy.

It's also important to assess limb perfusion in patients with PVAD and perform reperfusion in case of compromised flow. Robust observational data have shown improved survival in patients with cardiogenic shock with utilization of a protocol-based multidisciplinary approach. On the horizon are large randomized control trials to assess for best treatment strategies in patients with cardiogenic shock.