Al parecer la imagen del ECG3 no puede ser vista en tamaño mas grande, lo voy a subir de nuevo y la discusion interpretacion de el. Me entere Gracias al Dr Carlos Ruiz que fue muy gentil al comunicarmelo y asi tratar de corregir. Bueno espero que asi sea Buen dia.
Discussion ECG 3
This tracing exhibits sinus rhythn1 at 68 beats per rninute, with 2:1 AV block (ventricular rate 34 beats per rninute)- The ORS cornplexes have the pattern of left bundle branch block- The PR intervals are norrnal in the conducted complexes-
The atrial rhythrn is nearly regular, but the PP cycles that contain a ORS are 20 – 30 rns shorter than those immediately before and after that do not contain a QRS- This variation in sinus rate in 2:1 or higher grade AV block has been terrned ventriculophasic arrhythmia ln the presence of 2:1 AV block with a slow ventricular rate, the possibility n1ust be considered that the AV block rnay be cornplete, with the ventricular rate only coincidentally exactly one half of the atrial rate- Longer recordings are helpful in detecting this condition (sometimes tern1ed “hookin • ” or “acchrocha • e’ but even short recordings usually show more variation in the PR intervals than is seen here. 2:1 AV block may be either AV nodal (Type 1) or infranodal (Type 2). The distinction cannot be made with certainty when only surface ECG recordings with constant 2:1 block are available. Long recordings often show changes from the constant 2:1 ratio, with periods of either Type 1 block (Wernckebach) or Mobitz Type II block, providing reliable clues to the presence of underlying AV nodal, or of infranodal block. A narrow ORS complex in the presence of 2:1 block would almost rule out infranodal block, but a wide complex, as seen in this tracing, is consistent with either condition. Long PR intervals favor
AV nodal block, as does a PR interval that varies inversely with the RP interval.
The clinical setting has some predictive value in distinguishing the AV nodal and infranodal forms of 2:1 AV block. Acute inferior infarction and digitalis toxicity virtually always cause AV nodal block, while acute anterior infarction and chronic conduction systern disease in the elderly with syncope are more likely to be associated with infranodal block.
Langendorf R, Cohen H, Gozo EG Jr-
Observations on second degree
atrioventricular block, including nevv criteria
for the differential diagnosis betvveen Type I
and Type ll block. Arn J Cardiol 1972;29:111-9.
Rardon DP, Miles VVM, Mitrai RD, Klein LS,
Zipes DP. Cardiac Electrophysiology, From
Cell to Bedside- In: Zipes DP, Jalife J, eds-
Atrioventricular block and dissociation. 2nd
Edition ed- Philadelphia: VV-B- Saunders;