ECG changes in Acute severe Asthma

Pulmonary Medicine Blog By Dr Deepu

Reversible ECG changes in Acute severe Asthma

Dear Friends I got a call from the emergency department to treat a patient who was gasping for air, the intern at the ER department informed me that the patient had RAD, RBBB and P pulmonale, After examining the patient and taking proper history from the attendants we came to know that the patient is an asthmatic and this was an acute asthmatic attack. Then the intern was baffled by the ECG changes, he thought the event to be a acute cardiac event, I then explained him the ECG changes which are seen in acute asthma. I thought to share the same with you

Here are the ECG changes in Acute Severe Asthma

1.     Sinus tachycardia

2.      Right axis deviation

3.      P pulmonale 

4.      Precordial leads -  voltage of the "p" wave is reduced

5.      Poor progression of the R wave in the precordial leads and marked persistence of the S wave in the left precordial leads

6.      Right bundle branch block

7.      Ventricular premature complexes

8.     Atrial enlargement

9.     Transient ST-segment depression or elevation     in inferior leads ; T-wave abnormalities

10.                        Ventricular repolarization shows a lowered J point with an upward oblique ST segment in the peripheral leads

The mechanism of these electrocardiographic changes appears to depend on the vertical position of the heart caused by over expansion of the lungs and pulmonary arterial hypertension

What are the causes of ECG changes???

1.     Adrenergic stimulation

2.     Hyperventilation

3.     Hyperinflation

4.     Primary or secondary coronary insufficiency

5.     Severity of ECG signs correlates with the degree of airway obstruction.

So, Various ECG changes can occur in acute severe asthma which are nonspecific and these may mimic an acute cardiac event and can cause diagnostic dilemma, most of these changes are reversible usually within 10 days of treatment