Here is a nifty ECG case with two unrelated — but interesting — findings on one ECG tracing. One, a life-threatening diagnosis, and the other, a rare incidental finding leading to heart failure in this patient.
An 81-year-old, previously healthy male presents with recurrent syncope. He has also noted increasing dyspnea and lower extremity edema for the past year; it has been mild, and thus he never sought medical attention. Here is his ECG:
ECG Finding #1 - Life Threatening
The rhythm is sinus (upright P waves in lead II), but with third-degree atrioventricular (AV) block, also known as complete heart block. Look at the rhythm strip at the bottom in V1. You can march out the P waves and see they are not at the same rate as the QRS complexes.
Here is what you should know about third-degree AV block:
The P waves are not able to conduct at all through the AV node to the ventricles.
P waves (atrial depolarization) are at a different rate than the QRS complexes (ventricular depolarization). This is called "AV dissociation."
The QRS rate is usually quite slow and originates at the AV junction (junctional escape, narrow QRS, rate 40-60) or in the ventricles (ventricular escape, wide QRS, rate 20-40).
Symptoms of bradycardia are usually present, including syncope, weakness, dyspnea and heart failure.
A permanent pacemaker (PPM) is the treatment of choice.
Here is another example of third-degree AV block:
Here are even more examples:
ECG Finding #2 - Rare Cause of Heart Failure
This patient was found to have "Apical Hypertrophic Cardiomyopathy" — also known as "Yamaguchi syndrome" — a variant of hypertrophic cardiomyopathy. This can lead to slowly progressing diastolic congestive heart failure.
The ECG findings of apical hypertrophic cardiomyopathy include giant T-wave inversions in the precordial leads. Here is another ECG example of apical hypertrophic cardiomyopathy, with the arrow pointing at the giant T-wave inversions:
Here is our patient's echocardiogram showing abnormal left ventricular hypertrophy only towards the cardiac apex (top of the image):
Some points to know about apical hypertrophic cardiomyopathy:
Treat with verapamil or diltiazem (dihydropyridine calcium channel blockers) or beta-blockers to lower heart rate, allowing for more diastolic filling time.
There are no data to support disopyramide in this disease, as there is in typical hypertrophic obstructive cardiomyopathy (HOCM).
Surgical apical myomectomy is reserved for refractory cases.
I have only had one patient undergo apical myomectomy. That patient developed severe systolic dysfunction and severe mitral valve regurgitation requiring surgical repair about 2 years later!
- by Steven Lome, DO, RVT