A 53-year-old man suffers a cardiac arrest and his wife calls paramedics, who arrive a few minutes later and begin resuscitative measures. A regular heart rate is established after about 40 minutes of resuscitative efforts as he is being transported to the hospital. A thrombolytic agent is administered on admission. Which of the following cellular changes is most likely to now be occurring within his myocardium? <image 1> 
['Apoptosis', 'Free radical injury', 'Heterophagocytosis', 'Squamous metaplasia']