A new electrocardiographic concept: V1-V2-V3 are not only horizontal, but also frontal plane leads

Different degrees of anterior displacement of QRS complex

Electrocardiogram of a patient affected by hypertrophic cardiomyopathy showed normal PR and QRS intervals and signs of left ventricular hypertrophy. In leads I,V5 and V6 the initial q waves were absent. A subsequent electrocardiogram revealed the appearance of prominent anterior QRS forces expressed by a change from rS to R pattern in leads V2 and V3 with a tall R wave in V2. PR and QRS intervals and QRS axis remained substantially unchanged. Other electrocardiograms showed day-to-day variations of the anterior displacement of QRS complex. The different degrees of anterior displacement appear to be an expression of an underlying left septal fascicular block, but a diagnosis cannot be made with certainty.

An interesting electrocardiogram caused by lead reversal

BACKGROUND

During normal sinus rhythm, atrial depolarization is conducted from right atrium to left atrium through Bachmann's bundle, and a normal P wave axis which is measured on the frontal plane is between 0º and + 75º. The change of P wave polarity is helpful for the analysis of origin point.

CASE PRESENTATION

We report a patient with negative P wave in lead I. The characteristics of QRS complex in leads V1 to V6 are helpful to preliminarily differential diagnosis. The 12-lead electrocardiogram (ECG) with correct limb leads (right arm-left arm) placement shows sinus rhythm with complete right bundle branch block (RBBB).

CONCLUSIONS

The change of P wave polarity as well as characteristics of QRS complex can help identify limb-lead reversals.

Intermittent isolated anterior displacement of QRS complex - Differential diagnosis

BACKGROUND

The proposed criteria for diagnosis of left septal (middle) fascicular block (LSFB) appear to be conflicting. Moreover, it has been claimed that isolated anterior displacement (AD) of QRS complex could be a manifestation of a conduction delay of the right bundle branch, besides of LSFB. The purpose of the present study was to better define the etiology of AD through an analysis of the case reports dealing with intermittent AD, published up to now.

METHODS

PubMed search was performed to include all case reports dealing with intermittent AD occurring spontaneously, with an available 12‑lead electrocardiographic recording. Pertinent data were extracted from the papers for further analysis.

RESULTS

Eighteen case reports were found in the literature; in all cases intermittent AD was attributed to LSFB. In all cases AD was associated to changes of initial QRS forces, characterized by disappearance of septal q waves (in I and V6) and/or appearance of a small q wave in leads V1-V3. Morphology of terminal QRS forces, analysed for the first time, was unchanged in 90% of cases. Some Isolated ADs observed during induction of premature atrial extra-stimuli and recorded by vectorcardiographic tracing and some electrocardiographic leads were attributed to a conduction delay of the right bundle branch. In this case, initial QRS forces did not change and terminal QRS forces shifted to the right.

CONCLUSIONS

In the presence of intermittent isolated AD, a differential diagnosis between LSFB and a conduction delay of the right bundle branch appears to be possible by the analysis of initial and terminal QRS forces. Instead, the diagnosis of permanent LSFB remains a challenge.

A proposal for better visualization of Aslanger pattern

In the context of reporting a case of a patient with Aslanger pattern, the application of additional leads in the frontal plane is proposed to facilitate the recognition of this condition - indicating occlusive myocardial infarction - as eligible for the current ST-segment elevation myocardial infarction (STEMI) criteria and consequently for immediate reperfusion strategy recommendation.

A puzzling overnight change in the QRS morphology

Pacemakers set in a bipolar pacing mode often result in no discernible spikes on surface 12‑lead ECG registrations. In this situation, left axis deviation combined with wide QRS can help to identify the paced ECG morphology. We present a case of a non-pacemaker dependent patient whose normal atrioventricular conduction also appeared as atypical left axis deviation with wide QRS on the ECG. These two depolarization-repolarization morphologies, and the switch between the two raised differential diagnostic questions. The case also illustrates a paced ECG demonstrating the concept of Littmann: a close relationship between leads V2 and aVL.

Clinical and electrocardiographic features in acute total left main coronary artery occlusion without collateral circulation

BACKGROUNDS

Study concerning the clinical features, electrocardiogram (ECG) findings and outcomes in patients presenting with acute total occlusion of left main coronary artery (LM) without collateral circulation is limited.

METHODS

25 patients with acute total LM occlusion without collateral circulation by emergency coronary angiography, from muti-center registry, were retrospectively studied. The clinical and angiographic characteristics, ECG and in-hospital mortality were reviewed.

RESULTS

Nineteen patients (76%) presented with cardiogenic shock. Twelve (60%, 12/20) patients had coronary slow flow or no reflow phenomenon after primary percutaneous coronary intervention (PCI). The in-hospital mortality rate was 88% (n = 22). All the patients presented with ST-segment elevation myocardial ischemia (STEMI) pattern, mostly involving leads I, aVL, V2, V3, V4, V5 and ST-segment depression in leads II, III and aVF.

CONCLUSIONS

Acute total LM occlusion without collateral circulation portends high in-hospital mortality. Anterior ST elevation in the precordial leads from V2 to V4 through V6, and ST elevation in leads I and aVL, accompanying with ST depression in the inferior leads is associated with acute total LM occlusion without collateral circulation.

[Vexillology on the electrocardiogram. South Africa´s flag sign]

The electrocardiogram (ECG) is a test that will allow making life-saving decisions. It has different patterns, and differential diagnoses, like the pattern of acute coronary syndrome with an elevation of the high lateral ST segment, which is called the sign of the flag of South Africa. We present the case of a 44-year-old patient presented with typical chest pain; the ECG showed ST-segment elevation in the DI, DII, AVL - V2, and ST depression in DIII, corresponding to an acute coronary occlusion with a compromise of the lateral segment of the heart. This ECG pattern is known as the flag sign of South Africa. The early recognition allowed the decision to perform immediately pharmacological reperfusion therapy and rescue angioplasty.