Hypertrophy and the ECG Flashcards
What is the definition of hypertrophy?
An adaptive response to pressure, volume stress and mutations. It leads to an increase in the thickness of the myocardium.
What are the two types of hypertrophy?
Concentric hypertrophy is a narrowing of the walls, causing the ventricular volume to decrease, while eccentric hypertrophy is a decrease in the thickness of the walls, causing the ventricular volume to increase.
What relation do preload and afterload have to the two types of hypertrophy?
An increase in preload will lead to eccentric hypertrophy, while an increase in afterload will lead to concentric hypertrophy.
What changes can be seen on an ECG during right atrial hypertrophy?
A peaked P-wave of 2.5mm in leads 2, 3 and aVF and 1.5mm in leads V1 and V2.
What changes can be seen on an ECG during left atrial hypertrophy?
A broad, M-shaped P-wave in lead 2 and a biphasic P-wave in lead V1.
What changes can be seen on an ECG during right ventricular hypertrophy?
Right axis deviation of 110 degrees or more, a dominant R-wave in V1, a dominant S-wave in V5 or V6, a QRS duration of less than 120ms (so that RBBB can be ruled out).
What changes can be seen on an ECG during left ventricular hypertrophy?
Both voltage and non-voltage criteria must be found, the voltage criteria require the S-wave in V1 and the R-wave in V5 or V6 must equal more than 35mm. The non-voltage criteria include an increased R-wave peak time in lead V5 or V6, and a left ventricular strain pattern (which is ST depression and T-wave inversion in V5 or V6).
