Narrow QRS Complex: Causes & Reasons

Possible Causes for Narrow QRS Complex

In summary, although atrial flutter with regular narrow QRS complexes is often a knee-jerk diagnosis, care must be taken to establish the AV relationship. [ahajournals.org]

To the Editor: Adenosine is the treatment of choice for tachycardia with narrow QRS complexes involving the atrioventricular node as part of its reentrant circuit 1. [nejm.org]

The QRS complex is narrow, implying a supraventricular mechanism, and each QRS complex is preceded by a P wave with a constant PR interval. [reliasmedia.com]

Atrial Fibrillation

On an ECG (EKG), atrial fibrillation is characterized by absence of P-waves and irregular narrow QRS complexes. [youtube.com]

QRS complexes are typically narrow; a wide complex may occur with intraventricular conduction defects or Wolff-Parkinson-White syndrome. [merckmanuals.com]

Supraventricular Tachycardia

QRS complex. [en.wikipedia.org]

Narrow QRS Complex SVT. When tachycardia has a narrow QRS complex, it's much easier to diagnose it as supraventricular tachycardia. [pulmccm.org]

On electrocardiography, a narrow QRS complex tachycardia was evident. After carotid sinus massage, the patient immediately returned to sinus rhythm. [ncbi.nlm.nih.gov]

Paroxysmal Nodal Tachycardia

Diagnostic steps for any type of PSVT include obtaining the patient history and a 12-lead ECG, which typically shows tachycardia and narrow QRS complexes. [amboss.com]

QRS complex. [en.wikipedia.org]

Most types of SVT have narrow QRS complexes. [aafp.org]

Paroxysmal Supraventricular Tachycardia

QRS complex. [en.wikipedia.org]

A 40-year-old man was admitted because of 180 beats/min regular narrow QRS-complex tachycardia. [ncbi.nlm.nih.gov]

PSVT is a regular narrow QRS complex tachycardia (Figure 3). The QRS complex is of normal width, usually less than 0.08-0.10 seconds in duration. [patientcareonline.com]

Third Degree Atrioventricular Block

If the AV block is within the AV junction, the escape rhythm has narrow QRS complexes unless bundle branch block coexists. [en.my-ekg.com]

When the conduction starts within, or close to, the atrioventricular node, a narrow QRS complex escape rhythm is seen. [cardionetics.com]

Nodal blocks occur within the AV node and usually result in a narrow QRS complex with a ventricular escape rate greater than 40 beats per minute (bpm). [cancertherapyadvisor.com]

Paroxysmal Ventricular Tachycardia

Verapamil, or diltiazem if narrow QRS complex. [quizlet.com]

Figure 1 12-lead ECG showing a burst of non-sustained polymorphic tachycardia elicited by Valsalva manoeuver during a narrow QRS-complex tachycardia (210 b.p.m.). [academic.oup.com]

PSVT is a regular narrow QRS complex tachycardia (Figure 3). The QRS complex is of normal width, usually less than 0.08-0.10 seconds in duration. [patientcareonline.com]

AV Block Mobitz I

However, none of these P waves will be followed by a narrow QRS complex as nothing is being conducted through the AV node. [nurseyourownway.com]

Nodal blocks occur within the AV node and usually result in a narrow QRS complex with a ventricular escape rate greater than 40 beats per minute (bpm). [clinicaladvisor.com]

In proximal block the origin of escape rhythm is located above the His bundle bifurcation, QRS complexes are narrow, and their rate is 40 to 60/min (see Figure 3.2-2). [empendium.com]

AV Block Mobitz II

Nodal blocks occur within the AV node and usually result in a narrow QRS complex with a ventricular escape rate greater than 40 beats per minute (bpm). [clinicaladvisor.com]

In proximal block the origin of escape rhythm is located above the His bundle bifurcation, QRS complexes are narrow, and their rate is 40 to 60/min (see Figure 3.2-2). [empendium.com]

The electrocardiogram showed high degree AV block with narrow QRS complexes. [ncbi.nlm.nih.gov]

Second Degree Atrioventricular Block

Long-term follow-up studies of subjects with type I block and narrow QRS complexes have however produced rather conflicting results. [ncbi.nlm.nih.gov]

Generally, it may be distinguished by the width of the QRS complex; a narrow QRS complex suggests nodal block, while a broad QRS complex indicates an infranodal block [ 1, [jaclinicalreports.springeropen.com]

Nodal blocks occur within the AV node and usually result in a narrow QRS complex with a ventricular escape rate greater than 40 beats per minute (bpm). [clinicaladvisor.com]

Atrioventricular Junctional Rhythm

Narrow complex QRS. No P waves. Heart rate fast. Treatment Amiodarone to control the rhythm, electrical cardioversion is not used. [en.wikipedia.org]

Narrow QRS complex tachycardias. Mayo Clin Proc 1995;70:371–5 PubMed CrossRef Google Scholar 3. Kadish A, Passman R. [link.springer.com]

The rate is faster, and the QRS complexes narrow, both conditions causing a better cardiac output than wide QRS complexes and extremely slow rates. [ecgguru.com]

Supraventricular Tachycardia with Aberrant Conduction

NARROW QRS COMPLEX (≤ 0.09 s) WIDE QRS COMPLEX (> 0.09 s) Atrial fibrillation or Atrial flutter Ventricular tachycardia Sinus tachycardia Unusual SVT Supraventricular Tachycardia [nhcps.com]

In the lower tracing aberration, when heart rate slows down the aberration with wide QRS complexes disappear and narrow QRS complexes reappear. [metealpaslan.com]

Narrow QRS, normally (can be wide complex): Usually unless there is a bundle branch block. [quizlet.com]

Tachyarrhythmia

[…] interval is shorter than PR interval QRS complex Orthodromic AVRT: narrow QRS complex Antidromic AVRT: wide QRS complex with delta waves AV nodal reentry tachycardia (AVNRT [amboss.com]

Sinus tachycardia • ‘Normal’ p wave before every QRS • Narrow QRS complex (assuming no aberrancy / accessory pathway) • Rough guide to maximum predicted rate ~220 – age but [slideshare.net]

The QRS complex in most SVTs is narrow (QRS <120 ms). [unboundmedicine.com]

Atrial Tachyarrhythmia with Short PR Interval

QRS complex common (orthodromic); regular, wide QRS complex uncommon (orthodromic or antidromic) if bundle branch block or aberrancy present Orthodromic AVRT: RP interval [explainmedicine.com]

Therefore, neither the short PR interval nor the narrow QRS complexes characterized these forms of pre-excitation. [heart.bmj.com]

QRS complex (< 120 msec); regular, wide QRS complex (≥ 120 msec); may not see any P-wave activity in either type (atypical or typical) Atypical AVNRT: RP interval > PR interval [explainmedicine.com]

Lown-Ganong-Levine Syndrome

Therefore, neither the short PR interval nor the narrow QRS complexes characterized these forms of pre-excitation. [ncbi.nlm.nih.gov]

QRS complex common (orthodromic); regular, wide QRS complex uncommon (orthodromic or antidromic) if bundle branch block or aberrancy present Orthodromic AVRT: RP interval [explainmedicine.com]

Case 1, with short PR interval and narrow QRS complexes had a short AH interval and intermittent right bundle-branch block. [ncbi.nlm.nih.gov]

Preexcitation Syndrome

Therefore, neither the short PR interval nor the narrow QRS complexes characterized these forms of pre-excitation. [heart.bmj.com]

Features of orthodromic AVRT are: Fast rate (usually approximately 140-250 beats per minute) Narrow QRS complexes (unless BBB or IVCD present) P waves retrograde, if seen [ecgguru.com]

Narrow QRS complexes. No evidence of delta waves. [lifeinthefastlane.com]

Bradyarrhythmia

Regular, narrow QRS complex tachyarrhythmias include. [merck.com]

Figure 2 Development of junctional rhythm with narrow QRS complexes with retrograde conduction of P wave. [nature.com]

Bidirectional Tachycardia

QRS complex (140 ms) and alternating left- and right-axis deviation. [onlinejacc.org]

"Narrow" QRS complex, i.e. <120 ms duration. Figure 2. Bidirectional ventricular tachycardia. [revespcardiol.org]

QRS complex (arguing against aberrancy). [journals.lww.com]

Sinus Tachycardia

Second, determine the width of the QRS interval: narrow QRS complex tachycardias are supraventricular (from the sinus node, the atria, and the atrioventricular junction) in [mdedge.com]

The 12‐lead ECG showed a narrow QRS complex tachycardia with a heart rate of 126 bpm, the morphology of the P wave being positive in lead II, III, and aVF, positive in DI, [onlinelibrary.wiley.com]

appropriate management (including possible urgent referrals) should begin immediately. 1 A stable patient with a regular rhythm and a narrow QRS complex can be further investigated [mdedge.com]

Diffuse Intraventricular Block

Mangiardi LM, Bonamini R, Conte M, et al (1982) Bedside evaluation of atrioventricular block with narrow QRS complexes: usefulness of carotid sinus massage and atropine administration [link.springer.com]

The QRS complex of the first conducted P wave is narrow and recurs in a similar pattern. [revespcardiol.org]

[…] with relatively narrow QRS. [rjmatthewsmd.com]

Atrioventricular Dissociation

We describe the case of a 22-year-old man who had frequent episodes of narrow QRS complex tachycardia with atrioventricular dissociation. [ncbi.nlm.nih.gov]

If the AV block is within the AV junction, the escape rhythm has narrow QRS complexes unless bundle branch block coexists. [en.my-ekg.com]

QRS complex) or the ventricle (wide QRS complex) to take over ventricular activation. [6] This rhythm strip reveals interference atrioventricular dissociation, as there is [emedicine.medscape.com]

Incessant Infant Ventricular Tachycardia

The block occurs at the AV node in about 75% of patients with a narrow QRS complex and at infranodal sites (His bundle, bundle branches, or fascicles) in the rest. [merckmanuals.com]

QRS complexes are narrow unless there is underlying bundle branch disease. [ahcmedia.com]

First-Degree Atrioventricular Block

Nodal blocks occur within the AV node and usually result in a narrow QRS complex with a ventricular escape rate greater than 40 beats per minute (bpm). [cancertherapyadvisor.com]

The underlying rhythm here is a junctional escape rhythm with narrow QRS complexes and a rate of approximately 65 beats/minute. [merckmanuals.com]

A narrow QRS complex suggests nodal arrhythmia and likely type I block, while a wide complex indicates an infranodal location and type II block. [cancertherapyadvisor.com]

Right Bundle Branch Block

QRS complex. [journals.viamedica.pl]

On arrival, an ECG was performed showing sinus tachycardia with a narrow QRS complex (figure 1). [bjcardio.co.uk]

A Mobitz type I block (Wenckebach phenomenon) with narrow QRS complex is almost always due to a lesion in the AV node. [ncbi.nlm.nih.gov]

Sinus Arrest

In junction rhythm we find narrow QRS complexes without the P waves (as the source of the signal is the AV node and not the atria). [health-tutor.com]

A baseline ECG confirmed sinus rhythm with a normal PR interval (124 ms) and narrow QRS complex (81 ms) with a normal corrected QT interval (383.2 ms). [casereports.bmj.com]

Typically, the atrial impulse propagates normally through the atrioventricular node and into the cardiac ventricles, resulting in a normal, narrow QRS complex. [allnurses.com]

Left Bundle Branch Block

complex and 32 with LBBB), post-GDMT LVEF was >35% in 39 narrow QRS complex subjects (56%) and 2 LBBB subjects (6%) (P < .0001). [ncbi.nlm.nih.gov]

In patients without PPI, mortality was lower in those with narrower QRS complex and transient LBBB. [ncbi.nlm.nih.gov]

METHODS AND RESULTS: This retrospective study comprises 107 patients with initially narrow QRS complex of whom 40 did not and 67 did develop persistent LBBB after TAVI. 12 [ncbi.nlm.nih.gov]

Conduction Disorder of the Heart

Beats PVC: Early wide bizarre QRS, no p wave seen PAC: abnormally shaped P wave PJC: Narrow QRS complex, no p wave or inverted p wave Sick sinus syndrome Brady-tachy: Arrhythmia [smartypance.com]

Regular, narrow QRS complex tachyarrhythmias include. [msdmanuals.com]

The QRS complex will be narrow. [physicianassistantexamreview.com]

Neonatal Cardiac Arrhythmia

QRS complex. [en.wikipedia.org]

Acute Therapy of Supraventricular Arrhythmias in the Pregnant Woman Narrow-QRS-complex Tachycardia Narrow-QRS-complex tachycardia is a cardiac rhythm with a rate faster than [ecrjournal.com]

QRS complex tachycardia [Figure 2] b. [onlinejets.org]

Atrial Bigeminy

QRS Complex) References 1. [journals.lww.com]

The P waves associated with the narrow QRS complexes are upright in II, III and aVF suggesting that the rhythm originates in the sinoatrial (SA) node. [mdmag.com]

[…] caffeine intake, fatigue, smoking, alcohol use, and emotional stress, as these factors have been linked to the occurrence of PACs.2 Table: Irregular Rhythms at Normal Rates (Narrow [journals.lww.com]

Ventricular Tachycardia

QRS complex. [en.wikipedia.org]

This results in a capture beat in which ventricular conduction occurs over the normal pathways, resulting in a normal-appearing (narrow) QRS complex. [sjo.org]

QRS complexes. [en.wikipedia.org]