Syncopated Rhythm

Author(s)	L.R.C. Dekker, R. Tukkie
NHJ edition:	2007:4,157
These Rhythm Puzzles have been published in the Netherlands Heart Journal and are reproduced here under the prevailing creative commons license with permission from the publisher, Bohn Stafleu Van Loghum.
The ECG can be enlarged twice by clicking on the image and it's first enlargement

Figure 1

A 65-year-old woman was admitted because of recurrent syncope. Her complaints were difficult to interpret due to mental impairment after cerebral haemorrhage ten years earlier. She was once found lying in the street after walking her dog. Her medical history further included congestive heart failure after several untreated myocardial infarctions and diabetes. Under treatment with oral antidiabetics, furosemide, ACE inhibitor, digoxin and aspirin, she was in functional NYHA class I/IV. A 12-lead ECG is shown in figure 1.

What is the most likely level of this 2:1 AV block and what explains the p-wave pattern?

Answer