Left ventricular unloading therapy using Impella 5.5 after emergency surgery for acute myocardial infarction mechanical complication: a case report

Abstract

Abstract Background Following an acute myocardial infarction (AMI), surgery for left ventricular free wall rupture (LVFWR) and ventricular septal rupture (VSR) has a high in-hospital mortality rate, which has not improved significantly over time. Unloading the LV is critical to preventing excessive stress on the repair site and avoiding problems such as bleeding, leaks, patch dehiscence, and recurrence of LVFWR and VSR because the tissue is so fragile. We present two cases of patients who used Impella 5.5 for LV unloading following emergency surgery for AMI mechanical complications. Case presentation A 76-year-old male STEMI patient underwent fibrinolysis of the distal right coronary artery. Three days later, he passed out and went into shock. Echocardiography revealed a cardiac tamponade. We found an oozing-type LVFWR on the posterolateral wall and treated it with a non-suture technique using TachoSil. Before the patient was taken off CPB, Impella 5.5 was inserted into the LV via a 10 mm synthetic graft connected to the right axillary artery. We kept the flow rate above 4.0 to 4.5 L/min until POD 3 to reduce LV wall tension while minimizing pulsatility. On POD 6, we weaned the patient from Impella 5.5. A postoperative cardiac CT scan showed no contrast leakage from the LV. However, a cerebral hemorrhage on POD 4 during heparin administration complicated his hospitalization. Case 2: A diagnosis of cardiogenic shock caused by STEMI occurred in an 84-year-old male patient, who underwent PCI of the LAD with IABP support. Three days after PCI, echocardiography revealed VSR, and the patient underwent emergency VSR repair with two separate patches and BioGlue applied to the suture line between them. Before weaning from CPB, we implanted Impella 5.5 in the LV and added venoarterial extracorporeal membrane oxygenation (VA-ECMO) support for right heart failure. The postoperative echocardiography revealed no residual shunt. Conclusions Patients undergoing emergency surgery for mechanical complications of AMI may find Impella 5.5 to be an effective tool for LV unloading. The use of VA-ECMO in conjunction with Impella may be an effective strategy for managing VSR associated with concurrent right-sided heart failure.

Keywords

• Impella
• Acute myocardial infarction
• Ventricular septal rupture
• Left ventricular free wall rupture.