What is electrical alternans on ECG?

Electrical alternans is defined as alternating QRS amplitude that is seen in any or all leads on an electrocardiogram (ECG) with no additional changes to the conduction pathways of the heart. This rhythm is typically associated with pericardial effusion via the “swinging heart” from the fluid surrounding the heart.

How do you check for Pulsus alternans?

Physical examination Next use a blood pressure cuff to confirm the finding: Inflate the blood pressure cuff past systolic pressure and then slowly lower cuff pressure towards the systolic level. If alternating loud & soft Korotkoff sounds are heard, pulsus alternans is indicated.

When do you see Pulsus alternans?

Pulsus alternans (during pulse palpation, this is the alternation of one strong and one weak beat without a change in the cycle length) occurs most commonly in heart failure due to increased resistance to LV ejection, as occurs in hypertension, aortic stenosis, coronary atherosclerosis, and dilated cardiomyopathy.

Why is there electrical alternans in cardiac tamponade?

Electrical alternans, i.e. alternating QRS voltage, is a specific but insensitive ECG finding of a large pericardial effusion with tamponade. It is caused by mechanical anterior–posterior swinging of the heart in the large fluid and is frequently seen in malignant causes such as metastatic lung or breast cancer.

What kind of ECG does pulsus alternans show?

Twelve-lead ECG showed sinus tachycardia, and pulsus alternans was evident on simultaneous plethysmographic waveform ( Figure, A) in the form of strong and weak pulses. Transthoracic echocardiogram revealed left ventricular global hypokinesia with reduced ejection fraction of ≈30% (Movie I in the online-only Data Supplement).

What is the meaning of the Pulsus alternans?

Pulsus alternans. Pulse pressure waveform displaying the variation in pressure between beats in pulsus alternans. Pulsus alternans is a physical finding with arterial pulse waveform showing alternating strong and weak beats. It is almost always indicative of left ventricular systolic impairment, and carries a poor prognosis.

How are electrical alternans related to pericardial effusion?

Electrical alternans is an electrocardiographic phenomenon of alternation of QRS complex amplitude or axis between beats and a possible wandering base-line. It is seen in cardiac tamponade and severe pericardial effusion and is thought to be related to changes in the ventricular electrical axis due to fluid in…

What kind of pulse has alternating strong and weak beats?

Pulsus alternans describes a regular pulse that has alternating strong and weak beats ( Fig. 15.1).