CardioExchange Archive

A 65-year-old African American woman with a history of hypertension, diabetes, and seizure disorder is brought to the ED via emergency medical services for respiratory distress requiring intubation. Two weeks earlier she was hospitalized for an exacerbation of acute diastolic heart failure; a transthoracic echocardiogram at that time documented an LV ejection fraction of 60% with inferolateral hypokinesis. Her current medications are amlodipine, metformin, and lamotrigine.

On her current arrival at the ED, she develops pulseless electrical activity requiring CPR for 5 minutes, after which circulation returns spontaneously. She has a heart rate of 122 beats per minute, a blood pressure of 112/74 mm Hg, and a ventilator-assisted respiratory rate of 14 breaths per minute. The patient is intubated but arousable, has diminished breath sounds, and has no murmur on cardiac examination. Her electrocardiogram is shown here:

Click image to enlarge

Questions:

1. What does the electrocardiogram show?

2. What treatment would you recommend next?

3. Should the patient undergo cardiac catheterization?  If so, why? If not, why not?

4. Should hypothermia be used in this situation? Explain your answer.

5. How does the patient’s neurologic status influence your decision?

Response:

James Fang, MD  February 21, 2014

1. What does the electrocardiogram show?

In the setting of a wall-motion abnormality on echocardiogram (e.g., underlying heart disease), this wide-complex tachycardia (at least 120 ms to my review), RBBB-type, should be considered ventricular tachycardia (or an accelerated idioventricular rhythm due to heart rate) until proven otherwise, although atrioventricular dissociation is not apparent. However, the slow heart rate increases the temptation to consider this either sinus tachycardia or supraventricular tachycardia with aberrancy (e.g., RBBB). Using the Brugada criteria, a diagnosis cannot be made definitively without resorting to morphology of the QRS complexes, which suggests slow VT or accelerated idioventricular rhythm. A definitive diagnosis requires slowing the ventricular response to discern atrial activity and/or having documentation of the tachycardia’s onset.

2. What treatment would you recommend next?

Intravenous amiodarone would be reasonable in this setting until the diagnosis is clear. If the patient remains stable, a beta-blocker could also be considered. Synchronized cardioversion with adequate sedation would also be reasonable if the blood pressure is unstable or other signs of instability are apparent.

3. Should the patient undergo cardiac catheterization?  If so, why? If not, why not?

In the setting of CAD risk factors (e.g., hypertension, diabetes) and a wall-motion abnormality on echocardiogram, CAD should be excluded. The patient’s episode of acute diastolic heart failure may have been related to dynamic mitral regurgitation in the setting of the inferior ischemia. Other etiologies, including pulmonary embolism, should also be considered in the differential diagnosis. An echo showing acute RV strain and/or PE protocol chest CT would be a reasonable test in the ED as well. Catheterization is not necessary emergently but should eventually be performed as part of the patient’s cardiovascular evaluation if an alternative diagnosis is not made.

4. Should hypothermia be used in this situation? Explain your answer.

Hypothermia is not necessary. Despite her PEA arrest and being intubated, the patient is arousable and not comatose.

5. How does the patient’s neurologic status influence your decision?

Her almost immediately arousable state suggests that the anoxic insult has been limited and would not therefore attenuate an aggressive approach to diagnosis or therapy. Her presentation was life-threatening and needs a diagnosis.

Follow-Up

Saurav Chatterjee, MD

February 27, 2014

It was decided that emergent catheterization would have a prohibitive level of risk for the patient. After extensive consultation with the attending physician and the patient’s family, an attempt was made to offer the patient the best possible chance at neurological recovery, by inducing hypothermia with surface cooling to 33°C. A CT scan ruled out acute intracranial pathology.

The patient was successfully cooled and then rewarmed, but unfortunately she never regained a meaningful level of consciousness. Brain imaging conducted at that time revealed diffuse neuronal injury, for which the cause was unclear given that the reported downtime of the patient was just a few minutes. Seven days after admission to the CCU, the family decided to proceed with terminal extubation, after multiple neurologic evaluations indicated that her prognosis was dismal.