ST Elevation Anterior “Spiked Helmet” Sign

Abstract

suggestive of ST-segment elevation myocardial infarction in patients who were found not to have ST-segment elevation myocardial infarction. 1 Typical of those cases were a critical illness, a unique dome-and-spike pattern always in the inferior leads, and high in-hospital mortality.We recently reported a case in which the "spiked helmet" sign appeared in the anteroapical leads ( Figure). 2 Coronary angiography excluded coronary artery disease as a cause of ST-segment elevation. The cause of death, as established by autopsy, was traumatic aortic dissection due to a car accident. The morphology of the ST-segment elevation resembled the second case in the series of Littmann and Monroe. The exact mechanism of this pseudo-STsegment elevation is not known, but in the case of inferior ST-segment elevation, the proposed mechanism was diaphragmatic movement or an acute rise in intra-abdominal pressure. In our case, an acute rise in intrathoracic pressure due to aortic dissection may have been the cause of the pseudo-ST-segment elevation. In reply: We thank Tomcsányi et al for their interest in our work. The presented case extends our observations by demonstrating that with a sudden rise in intrathoracic pressure, the spiked helmet pattern can also show up in the chest leads. As was typical of our series, their patient did not have myocardial infarction (according to standard diagnostic criteria) and did not survive to hospital discharge. Our purpose in describing the spiked helmet sign was to raise physician awareness of this potential electrocardiographic marker of a high risk of death. 1 We hope that if physicians can recognize the spiked helmet sign in real time, it will assist in the rapid evaluation and management of critically ill patients. The case presented by Tomcsányi et al is a further step in this direction. FIGURE.The "spiked helmet" sign. Atrial fibrillation and ST-segment elevation in leads V 2 through V 4 . The dome-and-spike sign is most pronounced in leads V 3 and V 4 . Reprinted from J Electrocardiol, 2 with permission from Elsevier.

Letter by Littmann Regarding Article, “Giant J Waves and ST-Segment Elevation Associated With Acute Gastric Distension”

“…In the original article and in subsequent publications, acute abdominal events such as ileus, bowel perforation, and gastric obstruction usually were associated with the spiked helmet pattern showing up in the inferior leads, whereas acute thoracic events such as aortic dissection, pneumothorax, and mechanical hyperventilation caused the spiked helmet sign in the chest leads. [2][3][4][5] Similar to the case of Hibbs et al, 1 normalization of the underlying noncardiac condition resulted in prompt resolution of the pseudo-ST-segment elevation. 5 We and others have hypothesized that the most likely cause of the spiked helmet sign was pulsatile epidermal stretch that occurred in concert with the cardiac cycle in the setting of an acute rise in intracavitary pressures.…”

“…5 We and others have hypothesized that the most likely cause of the spiked helmet sign was pulsatile epidermal stretch that occurred in concert with the cardiac cycle in the setting of an acute rise in intracavitary pressures. [2][3][4][5] In the case report by Hibbs et al also, the apparent ST-segment elevation seen in the lateral chest leads resembled the spiked helmet sign. An enlargement of leads V 3 through V 6 of their Figure 2 showed that the upright swing of the baseline started before the onset of the QRS complexes and therefore could not have reflected a true repolarization abnormality.…”

“…[2][3][4][5] I applaud Hibbs et al for providing another striking example in which an acute abdominal event resulted in an ECG pattern resembling ST-segment-elevation myocardial infarction. Because now multiple centers have observed this clinical-electrocardiographic phenomenon independently, [1][2][3][4][5] it may be time to educate providers who take care of critically ill patients of this strange ECG abnormality. Understanding the characteristics and clinical significance of the spiked helmet sign not only may help avoid unnecessary emergent cardiac catheterizations but also could assist in the early recognition and treatment of potentially life-threatening abdominal or thoracic events.…”

Helmet Sign on EKG: A Rare Indicator of Poor Prognosis in Critically Ill Patients

“…Several explanations for the appearance of this abnormal EKG findings include pulsatile contraction of the diaphragm in sync with the cardiac cycle [4,5] and other mechanisms of diaphragmatic activities including abnormal breathing patterns with unexplained respiratory artifacts [6] or repetitive epidermal stretch due to acute increase in intra-abdominal or intrathoracic pressures [7,8]. These findings often indicate the need to rule out acutely evolving events in the chest or the abdomen [9]. These EKG findings have also been known to commonly occur in the inferior leads and in which case, may point strongly to an acute abdomen.…”

“…These EKG findings have also been known to commonly occur in the inferior leads and in which case, may point strongly to an acute abdomen. Additionally, the presence of these EKG findings in the precordial leads may be more suggestive of acute rise in intrathoracic pressure with causes such as an aortic dissection, pneumothorax, pneumomediastinum or acute respiratory distress syndrome [7,8,9,10]. A link between phrenic nerve stimulation and the baroreceptor reflex has also been suggested to play a role in the presence of synchrony between diaphragmatic contractions and ventricular contractions [5].…”