Are Q waves normal in V1 and V2?

Results: Because of its intermittence in subjects with multiple ECGs, QS deflections in leads V1-V2 appeared most often to be an artifact of precordial lead placement. Prior myocardial infarction, or presence of clinical coronary disease was present in only about 20% of the cases.

Is there Q wave in V1?

Q-waves can be physiological (in aVR, V1 and III, and tiny Q’s laterally), secondary to depolarization abnormalities (LBBB, LVH, WPW), or pathological (acute or chronic).

What do Q waves on ECG mean?

By definition, a Q wave on the electrocardiogram (ECG) is an initially negative deflection of the QRS complex. Technically, a Q wave indicates that the net direction of early ventricular depolarization (QRS) electrical forces projects toward the negative pole of the lead axis in question.

What is V1 and V2 in ECG?

V1, V2 = RV. V3, V4 = septum. V5, V6 = L side of the heart. Lead I = L side of the heart. Lead II = inferior territory.

What is Q wave myocardial infarction?

Q wave myocardial infarction refers to myocardial infarctions that in a Q wave forming on the 12-lead ECG once the infarction is completed.

What is an abnormal Q wave?

Background: Abnormal Q waves (AQW) in the electrocardiogram are commonly ascribed to underlying myocardial infarction (MI). As an imperfectly specific sign of MI, the usefulness of AQW in identifying MI depends on its incidence in the population studied.

Where is the Q wave?

Q waves are normally seen in the inferior and left lateral precordial leads in pediatric patients. The duration of these Q waves is almost always less than 20 ms. The amplitude can be rather large (up to 14 mm)7, especially in infants.

Where is V3 placed?

V3 is placed directly between V2 and V4. V5 is placed directly between V4 and V6. V6 is placed over the fifth intercostal space at the mid-axillary line (as if drawing a line down from the armpit).

Where is V2 placed?

The proper location of V1 and V2 have not changed in many decades. They are located in the 4th intercostal space, just right and left, respectively, of the sternum. It is fairly easy to determine this spot using the angle of Louis as a landmark.

What is a transmural infarction?

A transmural myocardial infarction refers to a myocardial infarction that involves the full thickness of the myocardium. It was one believed that the development of Q waves indicated the infarction was “transmural;” however, autopsy studies failed to confirm this.

What clinical condition could one suspect if the Q wave is abnormal?

Abnormal Q waves on the electrocardiogram (ECG) usually represent remote or recent myocardial infarction.

What is normal Q wave in ECG?

Normal Electrocardiogram Q waves are likely to be present in more leads when the transitional zone is located on the right side of the precordium. The duration of the Q waves is 0.03 second or less. The amplitude usually is less than 0.2 mV, although it may reach 0.3 mV or even 0.4 mV.

What is a normal Q wave?

Origin of the Q Wave. The Q wave represents the normal left-to-right depolarisation of the interventricular septum. Small ‘septal’ Q waves are typically seen in the left-sided leads (I, aVL, V5 and V6)

What causes Q waves?

The usual cause of Q wave irregularities is a previous heart attack (MI – myocardial infarction) resulting in dead heart muscle tissue or thickening of the heart muscle possibly from insufficient blood flow to the heart.

What does the Q wave abnormalities mean?

Q-WAVE ABNORMALITIES. Q waves represent the initial phase of ventricular depolarization. They are pathologic if they are abnormally wide (>0.2 second) or abnormally deep (>5 mm). Q waves that are pathologically deep but not wide are often indicators of ventricular hypertrophy. Q waves that are both abnormally deep and wide imply myocardial infarction.

What is a physiological Q wave?

A pathological Q wave is a result of absence of electrical activity, following myocardial damage. They generally take several hours to develop after an MI, and usually persist indefinitely.