**1. Introduction**

The decrease of the cardiac electrical systole—short PR and QTc intervals in the same electrocardiogram, also known as "Breijo electrocardiographic pattern"—is increasingly studied by several authors. The vast majority of the time it can be overlooked in an electrocardiogram tracing. More than 127 cases have been studied and cross-checked. Its diagnosis is essential in avoidance of the most heartbreaking consequence, that is, avoidable death. Despite the fact that for many authors, the cardiac electrical systole comprises only from the beginning of the Q wave to the end of the T wave, that is, depolarization and repolarization of the ventricles the atria are also part of it. Therefore, the P wave, as well as the PR segment, must be a part of the electrical cardiac systole. When there is a shortening of the PR interval along with a shortening of the QT interval, we should talk about the *Decrease of cardiac electrical systole*. This peculiar electrocardiographic pattern is denominating the **Breijo pattern**: "A PR interval less than 0.120 s along with a QTc interval less than 0.360 s." It is typical in this type of patients, carriers of the **Breijo pattern**, to have some common peculiarities in all of them. 1. Unspecific

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symptoms that are considered mild, such as: Palpitations, usually nocturnal, which awaken the patient from the natural sleep. Profuse nocturnal sweating. Light-headedness feelings misinterpreted. 2. A feeling of chest pain very unspecified, not irradiated and whose electrocardiographic study is regarded, in the vast majority of cases, as nonspecific and atypical, since coronary alterations are not observed. 3. A personal background, in childhood, of seizures treated with antiepileptic drugs without the presence of an epileptic focus on the electroencephalogram. 4. Low levels of lythemia. 5. A preference for young age (up to 40) and male sex.

conclusions. We agree to Gollop, these values may vary; for us and with a broader context, the

Breijo Electrocardiographic Pattern

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There are many formulas to measure the amount of these ranges; the most used are *Bazett and* 

Like the R-R interval, the QT interval is dependent on the heart rate in an obvious way (the faster the heart rate, the shorter the R-R Interval and QT interval) and may be adjusted to

The length of the PR (or PQ) interval, of the QRS complex, of the ST segment and the corrected

If greater than 200 ms, it would be denominated like an *Auricle-ventricular block in any of its* 

The QRS complex should have a maximum length of 0.10 s. If it were longer lasting, we would

**Figure 1.** Graphical representation of a normal heart cycle. Indicating the waves, segments and intervals in time (abscissa)

be in front of a branch block in its different modalities (complete or incomplete).

improve the detection of patients at increased risk of ventricular arrhythmia.

standard QTc values are between 0.400 and 0.450 s in length).

QT interval, are all-important and must be valued in all cases.

The PR interval must be greater than 120 ms and lower than 200 ms. Otherwise, we would find a **"short PR"** if this is fewer than 120 ms.

*Fridericia* yet (**Figure 1**).

*variants.*

and millivolts (ordinate).

In 2008, Breijo-Marquez et al. [1–3] presented an electrocardiographic pattern, in which both the PR and QT intervals were shorter in milliseconds than what is regarded as acceptable limits.

They called this phenomenon as *Decrease of electrical cardiac systole"*[1], since both, depolarization and repolarization, atrial and ventricular, are lower in their standard lengths (PR interval and QT interval).

It is well known that, in an electrocardiogram, there are different waves, intervals, and segments.

They are as follows:


In spite of the repeated repetition of the image, we put it below to gain a better understanding:
