What is electrical alternans on ECG?
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.
Why are electrical alternans in 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 does cardiac tamponade look like on ECG?
The ECG criteria of cardiac tamponade we adopted was as follows: 1) Low QRS voltage in a) the limb leads alone, b) in the precordial leads alone or, c) in all leads, 2) PR segment depression, 3) Electrical alternans, and 4) Sinus tachycardia.
What P wave alternans?
P-wave electrical alternans is a beat to beat alternation in the morphology of the P- wave, the wave in an electrocardiogram corresponding to atrial depolarization.
What is the difference between Pulsus Paradoxus and Pulsus alternans?
Pulsus alternans is a pulse pattern in which there is alternating (beat-to-beat) variability of pulse strength due to decreased ventricular performance. This is sometimes seen in patients with severe CHF. Pulsus paradoxus indicates an exaggeration of the normal reduction of systolic blood pressure during inspiration.
What is Brugada syndrome ECG?
Brugada syndrome is a disorder characterized by sudden death associated with one of several electrocardiographic (ECG) patterns characterized by incomplete right bundle-branch block and ST elevations in the anterior precordial leads.
How is tamponade diagnosed?
How is cardiac tamponade diagnosed?
- Echocardiogram, to look at the fluid around the heart and heart motion.
- Electrocardiogram (ECG), to check the heart’s electrical rhythm.
- Chest X-ray, to see the heart anatomy.
- CT or MRI scan.
Why does electrical alternans happen?
Alternans due to cardiac motion is the most well-known mechanism of electrical alternans, encountered in large pericardial effusions and cardiac tamponade. The pendulous swinging motion of the heart in a fluid-suspended cavity in such situations effectively causes electrical alternans.
What changes visible to the QRS waveform with cardiac tamponade?
Low QRS voltage is a feature of cardiac tamponade but not of pericardial effusion per se. Our findings indicate that the presence and severity of cardiac tamponade, in addition to inflammatory mechanisms, may contribute to the development of low QRS voltage in patients with large pericardial effusions.
How do you check pulsus alternans?
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.
Why pulsus alternans occur in left ventricular failure?
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.
What is Type 3 Brugada pattern?
Type 2: It has ≥2 mm J-point elevation, ≥1 mm ST-segment elevation and a saddleback appearance, followed by a positive or biphasic T-wave. Type 3: It has either a saddleback or coved appearance, but with an ST-segment elevation <1 mm.