EKG of the Week 1/27/2007

Background
Apical Hypertrophic Cardiomyopathy is a specific variant of Hypertrophic Cardiomyopathy. This disease has been first described in Japan by Yamagutchi where the prevalence is much higher than in the western world. It is characterized by hypertrophy that is confined to the apex which causes a ace of spades like configuration in RAO on the left ventriculogram.

EKG Characteristics
Giant negative T waves and tall R waves in the left precordial leads are the ECG hallmarks of the Japanese form of apical hypertrophy as seen on the EKG seen on the tracing above. Typically T waves in V4-V5 has the greatest degree of T wave depth possibly due to their proximity to the apex of the Left Ventricle which may result from the reversal in the direction of the vector of repolarization or myocardial ischemia due to hypoperfusion of the hypertrophied ventricle. Other findings on EKG include Left Atrial Enlargement, Right Atrial Enlargement, Left axis deviation, and First Degree AV Block.

See www.askdrwiki.com for more EKGs.

EKG of the Week 1/18/2007

This EKG shows marked right axis deviation (Negative vector in Lead I and Postive Vector in Lead aVF) as well as loss of voltage across the precordium seen in V1-V6. If you look closely you will notice there are negative or inverted p waves in lead I and aVL which is a clue to the diagnosis. The differential for inverted p waves in lead I and aVL is Dextrocardia or Reversed Arm Leads. Since there is loss of voltage across the precordium this is Dextrocardia. See more interesting EKGs on www.askdrwiki.com

EKG of the Week 1/5/2007

This EKG shows a slow wide complex tachycardia with intermittent narrow complex beats. The 5^th and 10^th beats are sinus rhythm and close examination of these beats will give you a clue to the cause of the wide complex rhythm. In Leads II and III you can appreciate ST elevation indicating an acute current of injury due to a myocardial infarction. The wide complex beats therefore represent an Accelerated Idioventricular Rhythm or AIVR which is usually seen following reperfusion after an acute infarct.

Accelerated Idioventricular Rhythms are ectopic ventricular rhythms at rates between 40 bpm and 100 to 120 bpm. The ventricular origin of this rhythm can be demonstrated by the usual EKG criteria which include AV dissociation, fusion, and capture complexes. In this EKG the 4^th beat represents a fusion complex and the 5^th beath represents a capture beat proving that these beats are ventricular in origin. The incidence of Accelerated Idioventricular Rhythms following acute MI is reported to be between 8 and 36 percent. This rhythm can also be seen in patients with primarily myocardial disease, hypertensive, rheumatic, and congenital heart disease. It can also be caused by digoxin. See more on www.askdrwiki.com

www.AskDrWiki.com is Launched

The use of medical Wikis can be a powerful tool for physicians in practice, fellows, residents, and medical students. A community of medical providers from all over the world discussing and publishing on medical related topics will become an invaluable resource for a physician in the future. There are several obstacles to overcome including:
1. Verifying that the information inputted into a medical wiki is based on scientific literature and is peer reviewed.
2. Keeping the sites free of vandals and advertisers
3. Building a community that will regularly contribute to the wiki
4. Ensuring that patient confidentiality is not compromised.

I hope to solve the problems above and work to make medical wikis an everyday part of our practice.