Our patient was having an uneventful and ordinary day. He got his children off to school, and spent the morning at the office completing paperwork. By noon he had eaten lunch, and went to the company workout center. It was Wednesday, so it was arms day. He started as he always did with 20 minutes of cardio on the elliptical machine, then shoulders, biceps, triceps, forearms — big muscle to small muscle. It was at the end of his first rep of triceps that things changed.
He felt some dizziness, and the nausea began within 30 seconds or so. He couldn't hold himself upright, and he slouched sideways off the bench onto the ground, losing consciousness. Others had seen him slide to the floor, and tended to him immediately. He did not have a pulse, and chest compressions were started. Another person ran to get an AED, which advised a shock. A jolt of electricity, and remarkably he had a pulse and regained consciousness.
He was brought by ambulance to the ED, and said he felt fairly well except for minor chest wall pain from the CPR. The patient didn't have exercise-related chest pain or chest tightness, and denied a sense of racing heart or palpitation prior to the event. He had no previous cardiac history or exertional syncope. He had no family history of premature coronary artery disease, cardiomyopathy, or sudden cardiac death.
An emergent transthoracic echocardiogram was performed, and a parasternal long axis view is shown in Figure 1. Left ventricular hypertrophy was present, systolic function was at the lower limits of normal, and he had a mild asynchronous kinesis of the septum. Most notably, he had an inferolateral wall motion abnormality, with a suggestion of thinned myocardium over the segment.
A cardiac MRI showed an akinetic segment of marked myocardial thinning in the inferolateral wall of the mid left ventricle with near transmural delayed enhancement. This is consistent with sequelae of previous myocardial infarction and indicates nonviable myocardium in this territory. No evidence was seen for an acute or recent myocardial infarction.
The patient later reported treating himself for heartburn several months before his cardiac arrest, which could have been an unrecognized acute coronary event that resulted in scarring. The cardiac arrest appears to be a primary arrhythmic event probably mediated by a myocardial scar. He was treated with aspirin, beta-blockade, ACE inhibitor, and high-intensity statin even in the absence of underlying obvious coronary disease based on the presence of myocardial scar and suspicious previous symptoms. An ICD was placed for secondary prevention of sudden cardiac death.
Find a complete discussion of this case, two videos, and additional images on July 5 in the EMN iPad app and on July 12 in the Spontaneous Circulation blog on www.EM-News.com, where the EMN app can also be downloaded for free.