Dr. Usman's Cardiology Notes

How to differentiate whether right axis deviation is due to right bundle branch block or left posterior fasicular block? Differentiating between right axis deviation due to a right bundle branch block (RBBB) or a left posterior fascicular block (LPFB) can be challenging but can involve several key points: QRS Duration: RBBB often causes a widened QRS complex (>0.12 seconds) while LPFB typically doesn't cause as much widening. Presence of R/S Ratio in Lead I: In RBBB, Lead I often shows an R/S ratio less than 1, whereas LPFB displays an R/S ratio greater than 1. QRS Morphology in V1 and V6: In RBBB, V1 often shows an rSR' pattern (bunny ears) and V6 shows a wide, slurred S wave. In LPFB, V1 can show a qR pattern and V6 often has a small r wave followed by a deep S wave. Prolonged R-wave peak time in avF: Time from onset of the QRS to the peak of the R wave in aVF > 45 ms suggests LPFB. Associated Findings: RBBB is frequently associated with ST-T changes and a slurred S wav...

Understanding Normal and Abnormal Waves of Hepatic Vein Doppler on Echocardiography Echocardiography, particularly the Doppler assessment of the hepatic veins, provides valuable insights into the functioning of the heart and liver. By analyzing the hepatic vein Doppler waves, clinicians can evaluate conditions related to right-sided heart function, heart failure, and hepatic congestion. Normal Waves of Hepatic Vein Doppler: In a healthy individual, hepatic vein Doppler shows characteristic waveforms reflecting the normal flow of blood from the liver back to the heart. There are three main phases: 1. S Wave (Systolic Flow): This initial positive wave occurs during ventricular systole, indicating the forward flow of blood towards the right atrium. 2. D Wave (Diastolic Flow): Following the S wave, there's a transient reversal or cessation of flow during early diastole. It signifies the closure of the tricuspid valve and cessation of the blood flow. 3. A Wave (Atrial Contraction): The ...