Case Review, AMI Cardiogenic Shock
Case Review: Heart Recovery in AMI Cardiogenic Shock Patients
Bryan Kluck, DO, and Gautam Kumar, MD, discuss strategies for managing AMI cardiogenic shock cases and improving heart recovery in an interview conducted by George Vetrovec, MD, MACC, MSCAI, Professor Emeritus at VCU in Richmond, Virginia. Dr. Kluck is an interventional cardiologist, endovascular interventionalist, and vascular medicine specialist at Lehigh Valley Hospital in Allentown, PA. Dr. Kumar is an interventional cardiologist at Emory University Hospital in Atlanta, GA.
The first case Dr. Kluck and Dr. Kumar present is a 51-year-old male with no prior cardiac history who was jogging to the gym and was found down on a front lawn. EKG revealed no clear acute myocardial infarction, but high-grade stenosis of the left anterior descending (LAD) artery was seen in the cath lab. Balloon dilatation resulted in reasonable hemodynamics, no support was initiated, and patient was brought back to CICU when a second case arrived.
The second case was a 64-year-old male with unknown medical history who was found down in a campground. Bystander had initiated CPR and patient was shocked several times when EMS arrived. EKG demonstrated significant ST-segment elevation. A balloon and stent were placed across the lesion in the LAD and then flow stopped. The Impella® heart pump was placed due to elevated hemodynamics, notably elevated left ventricular end diastolic pressure. Hemodynamics improved and patient returned to CICU, at which time the first patient was found to be significantly hypertensive with severe pulmonary edema.
First patient returned to cath lab where Impella was placed and hemodynamics improved. Both patients left the hospital with normal or near-normal ejection fraction (EF 60% in Case 1; EF 45-50% in Case 2).
The physicians discuss door-to-unload time and their cardiogenic shock management strategies to deliver optimal patient outcomes. Dr. Kluck states that his institution has adopted a strategy wherein most patients are taken to the cath lab. Dr. Kumar explains that cardiogenic shock treatment is evolving and taking into account reperfusion injury and the need for significant ventricular unloading, even prior to attempting PCI. He notes support for these strategies in results from the STEMI DTU™ pilot trial which demonstrated that early unloading before reperfusion is associated with better outcomes. Dr. Kluck notes that after the slow reflow happened in the second case, he wished he’d put Impella in sooner.
Dr. Kluck and Dr. Kumar discuss the importance of cardiogenic shock management strategies, such as obtaining lactate levels and arterial blood gasses, to help determine whether patients are likely to benefit from going to the cath lab and see meaningful recovery. They also discuss the “biochemical tsunami” caused by inotropes. Dr. Kluck emphasizes key cardiogenic shock protocol considerations, such as the importance of placing Impella first, before interventions, so that cases don’t get into that storm and so that physicians don’t have to undo the storm on the back end. He calls the treatment of patients in the CICU with multiple rounds of pressors “wrong think.” His message for cardiogenic shock management is: “We really need to start early with mechanical support.”
Dr. Vetrovec concludes the discussion noting that while management of these patients could potentially have benefited from a cardiogenic shock guideline of earlier mechanical support, it is very satisfying and gratifying to see very sick patients, such as these 2 cases, receive support and leave the hospital with good heart recovery.