QRS Duration Prolonged: Causes & Reasons

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Possible Causes for QRS Duration Prolonged

Sick Sinus Syndrome Type 1

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Left Posterior Fascicular Block

As in LAFB, the QRS duration will by prolonged by approximately 0.01 to 0.04 s, but total QRS duration will not reach 0.12 second. Refer to Figure 1. [ecgwaves.com]

duration normal or slightly prolonged (80-110ms) Prolonged R wave peak time in aVF Increased QRS voltage in the limb leads [maricopaemergencymedicine.com]

’ complexes) QRS duration normal or slightly prolonged (80-110 ms) Prolonged R wave peak time in AVF > 45 ms Increased QRS voltage in limb leads No evidence of right ventricular [medicalexamprep.co.uk]

Left Anterior Fascicular Block

As in LAFB, the QRS duration will by prolonged by approximately 0.01 to 0.04 s, but total QRS duration will not reach 0.12 second. Refer to Figure 1. [ecgwaves.com]

Here we can see that the QRS duration is prolonged at 110 ms (but under 120 ms). We also note qR complexes in leads I and aVL and rS complexes in leads II, III and aVF. [ems12lead.com]

Diffuse Intraventricular Block

Nonspecific intraventricular block 2017 Billable/Specific Code Disorder of the atrioventricular conduction system characterised by a prolonged QRS duration (QRS duration greater [medicbind.com]

Nonspecific intraventricular block 2017 Billable/Specific Code Disorder of the atrioventricular conduction system characterised by a prolonged QRS duration (QRS duration [codelay.com]

Associated ECG findings include decreased P wave amplitude, widened QRS duration, progressive PR prolongation and, in a terminal phase, a sinusoidal ECG pattern. [clinicaladvisor.com]

Right Bundle Branch Block

We hypothesized that prolonged R' wave duration in lead V1 would extend the later portion of the QRS complex and can act as an indicator of reduced RV function in patients [ncbi.nlm.nih.gov]

Complete RBBB was found less often in control subjects (1.37%; P < .0001), and the QRS duration was more prolonged in patients with IVF: 139 ± 10ms vs 150 ± 14ms (P = .0061 [ncbi.nlm.nih.gov]

The QRS duration was more prolonged in patients with BS and CRBBB compared with age- and sex-matched controls: 170±13 versus 145±15 milliseconds in V1 and 144±19 versus 128 [ncbi.nlm.nih.gov]

Left Bundle Branch Block

The hallmark of LBBB is the prolonged QRS duration. A QRS duration of 120 ms (0.12 s) or more is required to diagnose a complete left bundle branch block. [ecgwaves.com]

CRT is a therapeutic option for patients with heart failure, sinus rhythm, prolonged QRS complex duration and reduced ejection fraction. [ncbi.nlm.nih.gov]

Patients with an LBBB according to Strauss showed a significantly more prolonged QRS duration (P CONCLUSIONS: Applying stricter criteria, only 37% of patients undergoing CRT [ncbi.nlm.nih.gov]

Bidirectional Tachycardia

This ECG has two distinct QRS morphologies alternating every other beat. The QRS complex duration is prolonged (wide). [healio.com]

Although the QRS duration during the arrhythmia was prolonged, it remained narrower than the patient’s intrinsic QRS with the LBBB. The arrhythmia spontaneously abated. [ahajournals.org]

One of the QRS complexes is upward concordant in the precordial leads (all upward) indicating a ventricular origin. [healio.com]

Bifascicular Block

As in LAFB, the QRS duration will by prolonged by approximately 0.01 to 0.04 s, but total QRS duration will not reach 0.12 second. Refer to Figure 1. [ecgwaves.com]

The QRS duration is modestly prolonged at 108 ms. There is a left axis deivation with rS complexes in the inferior leads and qR complexes in the high lateral leads. [ecgmedicaltraining.com]

The QRS duration will be slightly prolonged (the prolongation ranges between 0.01 to 0.04 seconds). [ecgwaves.com]

Torsade-De-Pointes Syndrome with Short Coupling Interval

duration prolongation due to slow conduction and intraventricular dyssynchrony. [innovationsincrm.com]

[…] premature atrial or ventricular contractions, previously described elsewhere. 4 Right ventricular apical (RVA) pacing alters left ventricular electrical activation, causing QRS [innovationsincrm.com]

Preexcitation Syndrome

The classic electrocardiogram in Wolff-Parkinson-White (WPW) syndrome is characterized by a short PR interval and prolonged QRS duration in the presence of sinus rhythm with [ncbi.nlm.nih.gov]

Subsequent studies have demonstrated that premature ventricular excitation, not delayed conduction, prolongs QRS-complex duration. [nejm.org]

[…] complex, but the similarity lies in the fact that the initial direction of QRS deflection is reversed and the total QRS duration is also prolonged. [frca.co.uk]

Low-Cardiac-Output Syndrome

QRS duration (QRSd; > or =120 ms) is an independent predictor of low cardiac output syndrome (LCOS) in patients with low left ventricular (LV) ejection fraction (EF) who [ncbi.nlm.nih.gov]

Remember that a LBBB and RBBB, by definition, prolong the QRS duration. [healio.com]

[…] information 1 Department of Cardiology, Başkent University Adana Teaching and Medical Research Center, Adana, Turkey. tacil@lycos.com Abstract This study determined whether prolonged [ncbi.nlm.nih.gov]

Third Degree Atrioventricular Block

The HV interval increased (mean 43%) and the QRS duration was prolonged (mean 24%). [ncbi.nlm.nih.gov]

Otherwise this block has no other effect on the ECG. 1° Atrioventricular Block Rate: Unaffected Regularity: Unaffected P-Waves: Unaffected PR Interval: Prolonged, >0.2 s QRS [ems12lead.com]

[…] complex (delta wave) representing early ventricular activation through normal ventricular muscle in region of the accessory pathway Prolonged QRS duration (usually > 0.10s [ecg.utah.edu]

Phenothiazine Poisoning

Typical EKG findings include prolonged QRS duration, prolonged QT duration, or ventricular dysrhythmias. [calpoison.org]

Beta Blocker Poisoning

This property, usually not evident at therapeutic doses, may significantly contribute to toxicity by prolonging QRS duration and impairing cardiac conduction. [emedicine.medscape.com]

It has nasty sodium channel blocking effects and it prolongs QRS duration; moreover it penetrates the blood brain barrier. [derangedphysiology.com]

Respiratory bronchospasm CNS lethargy, stupor, coma seizures (especially following propranolol OD, particularly if QRS duration >100msec) Metabolic Hyperglycemia, hypokalaemia [aic.cuhk.edu.hk]

Cardiac Dilatation

QRS duration Hypertrophy may cause a slight prolongation of the QRS duration because it takes longer to depolarize the large ventricular mass. [ecgwaves.com]

It does not, however, reach 0.12 s (such significant prolongation is due to intraventricular conduction defects ). [ecgwaves.com]

Propoxyphene Intoxication

Typical EKG findings include prolonged QRS duration, prolonged QT duration, or ventricular dysrhythmias. [calpoison.org]

HF) QT prolongation Tricyclic antidepressants A QRS duration >100 ms suggests blockade of cardiac fast sodium channels. [lifeinthefastlane.com]

Value of the QRS duration verus the serum drug level in predicting seizures and ventricular arrhythmias after an acute overdose of tricyclic antidepressants. [lifeinthefastlane.com]

Atrioventricular Dissociation

The ECG of all 3 patients showed right bundle branch block with very prolonged QRS duration (0.16 to 0.20 s). [ncbi.nlm.nih.gov]

QRS complex shape is unusual and of prolonged duration (usually >0.12 seconds). [patient.info]

[…] complex (delta wave) representing early ventricular activation through normal ventricular muscle in region of the accessory pathway Prolonged QRS duration (usually > 0.10s [ecg.utah.edu]

AV Block Mobitz II

The QRS duration is prolonged. [emdocs.net]

Otherwise this block has no other effect on the ECG. 1° Atrioventricular Block Rate: Unaffected Regularity: Unaffected P-Waves: Unaffected PR Interval: Prolonged, >0.2 s QRS [ems12lead.com]

[…] complex (delta wave) representing early ventricular activation through normal ventricular muscle in region of the accessory pathway Prolonged QRS duration (usually > 0.10s [ecg.utah.edu]

AV Block Mobitz I

The QRS duration is prolonged. [emdocs.net]

Otherwise this block has no other effect on the ECG. 1° Atrioventricular Block Rate: Unaffected Regularity: Unaffected P-Waves: Unaffected PR Interval: Prolonged, >0.2 s QRS [ems12lead.com]

[…] complex (delta wave) representing early ventricular activation through normal ventricular muscle in region of the accessory pathway Prolonged QRS duration (usually > 0.10s [ecg.utah.edu]

Tricyclic Antidepressant Overdose

[…] of the QRS duration (greater than 0.10 sec) (p less than 0.05), and a threefold increase in the prevalence of QTc prolongation (p less than 0.05). [ncbi.nlm.nih.gov]

Sodium bicarbonate is indicated in tricyclic overdose in the context of hypotension or significant ECG abnormalities (arrhythmias; prolonged QRS/QT duration). [icmcasesummaries.com]

Electrocardiographic changes include prolongation of the PR, QRS and QT intervals, nonspecific ST segment and T wave changes, atrioventricular block, right axis deviation [ncbi.nlm.nih.gov]

Crush Syndrome

Severe hyperkalemia (8 – 9 mmol/l) – atrial standstill, prolonged QRS duration, further peaking T waves. Life-threatening hyperkalemia (>9 mmol/l) – sine wave pattern. [ems1.com]

Moderate hyperkalemia (7 – 8 mmol/l) – flattened P wave, prolonged PR interval, depression of ST segment, peaked T wave. [ems1.com]

Supraventricular Tachycardia with Aberrant Conduction

The delta wave prolongs QRS duration to > 0.12 sec, although the overall configuration, apart from the delta wave, may appear normal. [merckmanuals.com]

QRS complex shape is unusual and of prolonged duration (usually >0.12 seconds). [patient.info]

Most of the parameters – rate, PR interval, and QRS duration – are normal. [ecgguru.com]

Heart Block

Alternatively, if the PR interval is normal and the QRS duration is prolonged, then it is most likely second-degree AV nodal block type II, and a pacemaker is probably warranted [healio.com]

Otherwise this block has no other effect on the ECG. 1° Atrioventricular Block Rate: Unaffected Regularity: Unaffected P-Waves: Unaffected PR Interval: Prolonged, >0.2 s QRS [ems12lead.com]

[…] complex (delta wave) representing early ventricular activation through normal ventricular muscle in region of the accessory pathway Prolonged QRS duration (usually > 0.10s [ecg.utah.edu]

Long QT Syndrome 2

Relationship between dominant prolongation of the filtered qrs duration in the right precordial leads and clinical characteristics in brugada syndrome. [med.niigata-u.ac.jp]

First-Degree Atrioventricular Block

BACKGROUND: Prolongations of PR interval and QRS duration on 12-lead electrocardiogram are associated with atrioventricular and interventricular/intraventricular dyssynchrony [ncbi.nlm.nih.gov]

[…] complex (delta wave) representing early ventricular activation through normal ventricular muscle in region of the accessory pathway Prolonged QRS duration (usually > 0.10s [ecg.utah.edu]

Although the PQ interval is prolonged, all P waves are followed by QRS complexes: there is no dropout of complexes In first degree AV block there is a prolongation of PQ duration [en.ecgpedia.org]

Incessant Infant Ventricular Tachycardia

Prolongation of QRS duration. Prolongation of PR interval. Disappearance of P waves. Wide bizarre biphasic QRS complexes (sine waves). Eventual asystole. [lifeinthefastlane.com]

A short PR interval of 50 ms was seen as well as a delta wave resulting in a prolonged QRS duration of 110 ms (Figure 1). [hindawi.com]

The QRS duration is not prolonged in this case, but due to the non-reactivity and low rate, this fetus will require pacing after birth. Fig. 10. [glowm.com]

Conduction Disorder of the Heart

[…] complex (delta wave) representing early ventricular activation through normal ventricular muscle in region of the accessory pathway Prolonged QRS duration (usually > 0.10s [ecg.utah.edu]

The only independent predictor of the need for a PM was a prolonged QRS duration, and the authors concluded that patients with a QRS of less than 128 ms after TAVI have no [revespcardiol.org]

When using a QRS duration ≥100 ms as a criterion of “prolonged” QRS (as in ref.[ 13 ]), 57 patients (27%) fell into this category, Table 2. [bmcmusculoskeletdisord.biomedcentral.com]

Anterior Pituitary Disease

As in LAFB, the QRS duration will by prolonged by approximately 0.01 to 0.04 s, but total QRS duration will not reach 0.12 second. Refer to Figure 1. [ecgwaves.com]

I and aVL Small R waves with deep S waves (= ‘rS complexes’) in leads II, III, aVF QRS duration normal or slightly prolonged (80-110 ms) Prolonged R wave peak time in aVL [lifeinthefastlane.com]

The QRS duration will be slightly prolonged (the prolongation ranges between 0.01 to 0.04 seconds). [ecgwaves.com]

Lenegre Disease

[…] occurs at 20-30 bpm </li></ul><ul><li>QRS duration prolonged </li></ul><ul><li>Does not  with atropine </li></ul><ul><li>Site of block distal to AV node </li></ul><ul><li [slideshare.net]

QRS duration, prolonged His-ventricle conduction time, and ventricular escape rhythms. [findzebra.com]

Patients with prolonged QRS duration, even without bundle branch block, are at increased risk for future pacemaker implantation and may warrant monitoring for progressive [thoracickey.com]

Right Ventricular Dilatation

QRS duration Hypertrophy may cause a slight prolongation of the QRS duration because it takes longer to depolarize the large ventricular mass. [ecgwaves.com]

QRS duration (QRS>180 ms), or inducible ventricular arrhythmias using programmed ventricular stimulation during electrophysiology study. 3 Because of the absence of long-term [revespcardiol.org]

It does not, however, reach 0.12 s (such significant prolongation is due to intraventricular conduction defects ). [ecgwaves.com]