There are significant cardiac abnormalities observed following subarachnoid hemorrhage (SAH) that varies depending upon the grade of SAH, but correlate with the degree of elevation of cardiac troponin I (cTnI). These effects are likely mitigated through sympathetic and parasympathetic dysfunction that results from global cerebral dysfunction following SAH. This chapter presents a case study of a 54-year-old male with no significant past medical history who suddenly developed a thunderclap headache. The patient underwent an uneventful ventriculoperitoneal shunt placement and after 2 more weeks in the neurosurgical intensive care unit (ICU) was transferred to the general care ward. The histopathology of neurogenic cardiac lesions is distinct from the coagulation necrosis observed following myocardial infarction. Both sympathetic overactivity and parasympathetic dysfunction result in a pro-arrhythmogenic state as well that worsens electrocardiogram (ECG) changes associated with myocardial necrosis.