Cardiac Arrhythmias (I)

Its no secret that Cardiology is my one-true-love. :)
I love it so much, I'm going to specialize in it, Insyaallah...

All of my favourite Internal Medicine teachers were great at teaching Cardiology, which I think definitely inspires me and a lot of my friends here to study well in this field. To name a few names, Elena Ivanovna Panova, Tatyana Anatolevna Nekrasova, Ilya Gregorevich Pachenko and my current teacher, the HOD of Cardiology, Svetlana Nikolaevna Botova. Dr. Nekrasova is an Endocrinologist by profession, but her knowledge of ECGs and Cardiology is extremely good. :)

Since yesterday was so cold, my group made a sad face and asked the HoD for a one-day break. If other groups want to call us "weak" and "lazy" so that they can appear as "hardworking" and "strong-willed", this is the chance for you to do so. The buses here were not heated AT ALL, and taking the bus for an hour is like sitting in the freezer. And upon reaching the bus stop, there was a 10-15 minute walk to the hospital in frigid cold weather of -27C. So yeah, I am weak. Lazy? Well, let's not go there. xD Let's call me....easygoing? Haha.

Anyway, today is officially my ECG day. Interpreting ECGs is not an easy job, for a medical student. For the cardiologists who picked up their first rhythm strip when I was in my diapers, of course its easy!! ^^

Here's a few pointers I learned from my attendings, esp. Ilya Gregorevich Pachenko, a.k.a. Bradley Cooper a.k.a McDreamy a.k.a. God of 4th Floor, 13th Hospital. Sometimes people refer to him as I.G.P or as the HoD~

Step 1 : Calculate rate

-          Count the R-waves in a 6-second rhythm strip and then multiply by 10

-          Find R waves that land on a bold line. Count the number of large boxes to the next R wave. If the 2^nd R is 1 large box away, the rate is 300, 2 box = 150, 3 box= 75, etc.

Step 2 : Determine regularity

-          Look at R-R distances

-          Regular (are they equidistant apart?), Occasionally irregular? Irregularly irregular?

Step 3 : Assess P waves

-          Is P wave present?

-          Do they look alike?

-          Are they regular?

-          Is there a P wave before each QRS?

Step 4 : PR interval

-          N: 0.12 – 0.2 seconds (3-5 boxes)

Step 5 : QRS duration

-          N: 0.04 – 0.12 seconds (But acc to Ilya, 0.04 – 0.10, not 0.12)

He He loves these 5 steps! :)) 

• Sinus Tachycardia is rate >100bpm (with sinus rhythm of course)
• P wave amplited often INCREASES and PR interval often DECREASES with increasing HR
•  RBBB, Complete has a QRS duration of >0.12 seconds
•  Secondary R (R') wave in lead V1 is usually taller than the intial R~
• ST segment depression and T inversion in leads V1-2
• QRS axis is usually normal!
• RBBB does NOT interfere with the ECG diagnosis of LVH or Q-wave MI (unlike its counterpart, LBBB)
•  Left Posterior Fascicular Block is diagnosed when
• RAD with mean axis between 100-180 degrees
• QRS duration between 0.08-0.1 seconds
• NO OTHER EXPLANATION for RAD is found (important~!)

• RAD explanations
• RVH
• Vertical Heart
• Emphysema
• PTE
• Lateral wall MI
• Dextrocardia
• Lead reversal
• WPW

 :) Are you having fun yet? Yes?? Hehe...Good, because Cardiology IS fun!! ^^ Most of the times anyway... ;)