The giant R wave of acute myocardial infarction.

Faillace, Robert T.; Akiyama, Toshio; Chang, Winshih

doi:10.1536/ihj.26.165

Cited by 8 publications

(2 citation statements)

References 23 publications

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“…As illustrated in figure 1, a giant R wave quickly developed during the first 4 min of coronary occlusion, and also later in time around 11-22 min. This particular finding has been reported in previous studies carried out in experiments with pigs (Chang et al 1989) and also in humans (Faillace et al 1985). However, those other studies did not focus their attention on the two different peaks in R a evolution.…”

Section: Ischemia-induced Ecg Changes In Depolarization and Repolarizsupporting

confidence: 69%

Characterization of ventricular depolarization and repolarization changes in a porcine model of myocardial infarction

Romero¹,

Ringborn²,

Demidova³

et al. 2012

Physiol. Meas.

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In this study, several electrocardiogram (ECG)-derived indices corresponding to both ventricular depolarization and repolarization were evaluated during acute myocardial ischemia in an experimental model of myocardial infarction produced by 40 min coronary balloon inflation in 13 pigs. Significant changes were rapidly observed from minute 4 after the start of coronary occlusion, achieving their maximum values between 11 and 22 min for depolarization and between 9 and 12 min for repolarization indices, respectively. Subsequently, these maximum changes started to decrease during the latter part of the occlusion. Depolarization changes associated with the second half of the QRS complex showed a significant but inverse correlation with the myocardium at risk (MaR) estimated by scintigraphic images. The correlation between MaR and changes of the downward slope of the QRS complex, [Formula: see text], evaluated at the two more relevant peaks observed during the occlusion, was r = -0.75, p < 0.01 and r = -0.79, p < 0.01 for the positive and negative deflections observed in [Formula: see text], temporal evolution, respectively. Repolarization changes, analyzed by evaluation of ST segment elevation at the main observed positive peak, also showed negative, however non-significant correlation with MaR: r = -0.34, p = 0.28. Our results suggest that changes evaluated in the latter part of the depolarization, such as those described by [Formula: see text], which are influenced by R-wave amplitude, QRS width and ST level variations simultaneously, correlate better with the amount of ischemia than other indices evaluated in the earlier part of depolarization or during the ST segment.

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Section: Ischemia-induced Ecg Changes In Depolarization and Repolarizsupporting

confidence: 69%

Characterization of ventricular depolarization and repolarization changes in a porcine model of myocardial infarction

Romero¹,

Ringborn²,

Demidova³

et al. 2012

Physiol. Meas.

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“…One theory suggests that severe myocardial ischemia leads to the release of intracellular potassium from cardiomyocytes, leading to a local intra-myocardial conduction delay with concomitant extracellular positive electrical gradient in the affected area while the rest of the heart is in repolarization, with a resultant unopposed accentuated and broad R wave in leads facing the area of acute severe ischemia [4-5, 7]. The changes in the terminal portion of the QRS complex are a consequence of the conduction abnormalities at the level of the Purkinje fibers, which normally develop only after a severe and prolonged episode of ischemia [10].…”

Section: Discussionmentioning

confidence: 99%

Transient Giant R Wave as a Marker for Ischemia in Unstable Angina

Chugh

Maraboto

Christia

et al. 2017

Cureus

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Unstable angina is a clinical diagnosis that may present with or without electrocardiographic changes. The “giant R wave” on electrocardiogram has been reported as a manifestation of acute ischemia; however, it is a rare finding in current clinical practice. We describe a case of a patient with unstable angina and a transient “giant R wave” pattern with a culprit lesion in the right coronary artery.

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