What causes widening of the QRS complex?

What causes widening of the QRS complex?

A “wide QRS complex” refers to a QRS complex duration ≥120 ms. Widening of the QRS complex is related to slower spread of ventricular depolarization, either due to disease of the His-Purkinje network and/or reliance on slower, muscle-to-muscle spread of depolarization.

What do peaked T waves indicate?

Tall T-waves (also called hyper-acute T waves) can be an early sign of ST-elevation myocardial infarction. The morphology of the T waves can begin to broaden and peak within 30 minutes of complete coronary artery occlusion, and thus may be the earliest sign of myocardial infarction on the EKG.

What type of arrhythmia has a widened QRS complex?

Wide QRS complex tachycardia can be originated by 3 main mechanisms1: Ventricular tachycardia (VT). Supraventricular tachycardia (SVT) with an aberrant conduction attributable to a preexisting bundle-branch block or functional bundle-branch block induced by the fast heart rate.

What causes tall peaked T waves?

Hyperkalemia: Hyperkalemia is a common cause of tall or peaked T waves.

What does it mean when the QRS is wider than normal?

A wider QRS may indicate that the bottom of the heart is contracting a little later than it should. Wide QRS is noted on ECG when there is a delay, or widening, in the part of the ECG called the QRS complex.

What happens during QRS complex?

As the name suggests, the QRS complex includes the Q wave, R wave, and S wave. These three waves occur in rapid succession. The QRS complex represents the electrical impulse as it spreads through the ventricles and indicates ventricular depolarization.

What does QRS complex stand for?

The QRS complex represents the electrical impulse as it spreads through the ventricles and indicates ventricular depolarization. As with the P wave, the QRS complex starts just before ventricular contraction.

What does abnormal QRS T angle mean?

An abnormal spatial QRS-T angle was associated with a higher risk of death from all causes [hazard ratio (HR) 2.33; 95% confidence interval (CI) 1.46-3.70] and especially a higher risk of sudden cardiac death (HR 2.99; 95% CI 1.04-8.60).

What does QRS complex represent on ECG?

A combination of the Q wave, R wave and S wave, the “QRS complex” represents ventricular depolarization. This term can be confusing, as not all ECG leads contain all three of these waves; yet a “QRS complex” is said to be present regardless.

How is the QRS complex described in atrial fibrillation?

The diagnosis of atrial fibrillation is confirmed with a standard 12-lead ECG. P waves are absent, coarse “fibrillatory waves” can frequently be seen and sometimes no atrial activity can be identified. The QRS complexes are “irregularly irregular”, with varying R-R intervals.

What causes the T wave?

The two main causes of these waves are myocardial ischemia and hypokalemia.

What would be indicated by a QRS complex that was large wide and slow?

What does a QRS complex look like on an ECG?

In this ECG, in addition to tall T waves (more peaked than in previous ECG), QRS complex is wide and has left bundle branch block pattern. There is ST segment depression and T wave inversion in the lateral leads, though the T waves are very tall and peaked in mid precordial leads.

How do you name the waves in the QRS complex?

Naming of the waves in the QRS complex is easy but frequently misunderstood. The following rules apply when naming the waves: A deflection is only referred to as a wave if it passes the baseline. If the first wave is negative then it is referred to as Q-wave.

What is a wide QRS complex?

QRS complexes are abnormally wide in the presence of bundle branch block (see Ch. 2), or when depolarization is initiated by a focus in the ventricular muscle causing ventricular escape beats, extrasystoles or tachycardia (see Ch. 3 ).

What is the difference between Q-wave and R-wave?

If the first wave is negative then it is referred to as Q-wave. If the first wave is not negative, then the QRS complex does not possess a Q-wave, regardless of the appearance of the QRS complex. All positive waves are referred to as R-waves. The first positive wave is simply an “R-wave” (R). The second positive wave is called “R-prime wave” (R’).