Atrial and Ventricular Enlargement Chapter 6 Cardiac Enlargement

Atrial and Ventricular Enlargement Chapter 6

Cardiac Enlargement dilation stretched congestive heart failure hypertrophy increase size of heart muscle fibers aortic stenosis

Cardiac Enlargement Increase amount of cardiac tissue How would this affect amount of depolarization? How could that affect an ECG?

Right Atrial Abnormality Overload of the right atria dilation hypertrophy Increase voltage of the P wave

Right Atrial Abnormality Normal P wave amplitude is less than 2. 5 mm and 0. 12 seconds in width. Abnormal P waves are typically taller than 2. 5 mm but not longer the 0. 12 sec.

Right Atrial Abnormality Causes: Pulmonary disease Congenital heart disease

Right Atrial Abnormality • Tall P waves in any of the following leads: • II, III, a. VF or sometimes V 1.

Right Atrial Abnormality P pulmonale artial enlargement due to severe pulmonary disease Atrial enlargement can occur in the absence of tall P waves.

Left Atrial Abnormality Left atria normally depolarizes after the right atria. Left atrial enlargement should prolong the P wave greater than 0. 12 sec. P wave height may be normal or increased

Left Atrial Abnormality CAD may produce wide P waves without left atrial enlargement.

• Left Atrial Abnormality Leads I and/or II may show notched P waves • • • (second hump due to delayed depolarization of the left atrium) (P mitrale: mitral valve disease) V 1 may show a bi-phasic P wave • • negative part is > 0. 4 sec. or 1 mm in depth (right atria is anterior to the left atria)

Left Atrial Abnormality Causes: Valvular heart disease Hypertensive heart disease Cardiomyopathies CAD

Right Ventricular Hypertrophy What do you think will happen to the ECG with ventricular hypertrophy?

Normal QRS V 6? V 1? FIG. 4 -6 V 1?

Normal QRS V 1 V 6

Right Ventricular Hypertrophy Consider right ventricular hypertrophy and V 1 NORMAL HYPERTROPHY

Right Ventricular Hypertrophy 1. In V 1, R wave is greater than the S wave 2. In V 1, T wave inversion (reason unknown) 3. Right axis deviation

Right Ventricular Hypertrophy Causes of RVH congenital heart disease atrial septal defects others Emphysema may mask signs of RVH

Left Ventricular Hypertrophy With LVH, the electrical balance is tipped even further to the left. Predominate S waves in the right chest leads Tall R waves in the left chest leads

Left Ventricular Hypertrophy • If S wave in V + R wave in either V 5 or V 6 > 35 mm (not specific indicator). 1 • R wave > 11 -13 mm in a. V • ST segment changes • Left axis deviation • Left atrial abnormality L

ST strain patterns

Left Ventricular Hypertrophy Causes: Hypertension Aortic stenosis Risks of LVH congestive heart failure arrhythmias

Left Ventricular Hypertrophy High voltage can be seen in normal people, especially athletes Hypertrophy in both ventricles the ECG will show more evidence of LVH