[Impact of experimental infarction of the right ventricle on P, Ta and QTa readings].
Right atrial (RA) damage was produced by subepicardial infiltration with 96 percent alcohol in 18 dogs' hearts. Anterolateral, right appendage and right side of interauricular band were injected. 19 surface readings, including right thoracic, abdominal (MD, ME, MI), and five direct atrial unipolar records were obtained using VR6 photographic paper and a direct-writing machine (Sanborn 150) with 4 channels at 50 and 100 mm/sec speed. Records were made in control conditions and immediately after infiltration as well as 120 minutes later. Premature atrial contractions and A-V block were provoked in order to measure, precisely, the QTa duration and its termination in the ventricular ST. Rate slowing, slight broadening of P and P-R as well and in 4 cases low right atrial rhythm were observed. Significant changes in the right thoracic leads and even in the V4-V5 leads, as well as in RA unipolars, were also demonstrated, that is: P-R segment elevation (injury vector pointing toward the RA), Qr or Wp waves (necrosis vector away from RA). Nevertheless, leads II, III and a VF showed q o w p waves with less significant Ta changes. Ischemic vector went away RA pointing toward the left one, magnifying the protuberance or irregularities on ventricular ST. The QTac was prolonged beyond VM + 0.04, with the greater one in RA leads. This behaviour was evidenced on premature blocked atrial contractions as well as in A-V block. Similar alterations of P wave can be observed in RA infarction as well in myocarditis.
G A
GA
Medrano
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A
de Micheli
A
A
Osornio
D000818:Animals; D005117:Cardiac Complexes, Premature / Q000209:etiology; D009202:Cardiomyopathies / Q000209:etiology; D004285:Dogs; D004562:Electrocardiography; D006325:Heart Atria; D006470:Hemorrhage / Q000209:etiology; D009203:Myocardial Infarction / Q000150:complications / Q000473:pathology / Q000503:physiopathology*; D009206:Myocardium / Q000473:pathology; D009336:Necrosis
Repercusiones del infarto experimental de la aurícula derecha sobre P, Ta y QTa.