HWN Suggests

Torsades de Pointes: Approach to resuscitation

A 46 year old female is referred into the emergency department after multiple syncopal episodes. Her family physician did blood work and found her to be hypokalemic. She is on venlafaxine for depression and amitriptyline for sciatica. She is currently on a course of moxifloxacin for her sinusitis and this morning took a dose of fluconazole for the resultant candidiasis. On arrival, she is alert and looks well. However, as the ECG is being performed, she slumps over and you see torsades de pointes:

Torsades de pointes is a ventricular tachycardia. In the unstable patient, cardiovert. In the pulseless, defibrillate. (The polymorphic nature of the rhythm may interfere with the defibrillator’s…

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  Torsades de Pointes

Torsades can be caused by either congenital long-QT syndrome or acquired long-QT syndrome (due to electrolyte abnormalities and/or medications). The vast majority of torsades results from acquired long-QT syndrome, which is the focus of this chapter.

Articles of Interest

Magnesium infusions for atrial fibrillation & torsade

Having a cardiac magnesium infusion protocol is very useful for torsade de pointes, where it may reduce the risk of recurrent cardiac arrest.

QT interval prolongation and torsade de pointes in patients with COVID-19 treated with hydroxychloroquine/azithromycin

The combination of HY/AZ significantly prolongs the QTc interval in patients with COVID-19. This prolongation may be responsible for life-threatening arrhythmia in the form of TdP. This risk mandates careful consideration of HY/AZ therapy in light of its unproven efficacy. Strict QTc interval monitoring should be performed if the regimen is given.

The Twisted Truth Identifying and Treating Torsade de Pointes in Surreptitious Drug Use

Abuse of loperamide, an antidiarrheal agent, for its euphoric effects is increasingly common in the current opioid epidemic. While its full cardiotoxic profile is not yet known, loperamide abuse should be considered in all patients with unexplained tachyarrhythmias and TDP

Torsades de Pointes Patient Testimonial: Steve Ciani

Steve Ciani, a bus driver and life-long Brooklyn resident lost consciousness while a mechanic was working on his vehicle. It turns out that Steve suffers from a rare heart condition called short-coupled toursades, which was treated by Dr. Yisachar Greenberg, Director of Electrophysiology and Pacing at Maimonides. Steve credits Dr. Greenberg and his cardiology team with his successful recovery.

Call “the Cleaners”

Drug-induced torsades de pointes (TDP) is the epitome of a therapeutic intervention gone awry despite the best intentions. Clinically indicated drug therapy, often involving medications that have no cardiac indications and are therefore assumed to be free of cardiac effects, unintentionally provoke QT interval prolongation and iatrogenic arrhythmias.

Common Antibiotics Cause Arrhythmias, Death And Everything Else

Shocking news—unless you are a physician or know healthcare—that commonly used antibiotics can cause death!

Drug-Induced QT Prolongation And Torsades de Pointes

There is no threshold of QTc prolongation at which TdP is certain to occur. A QTc greater than 500 milliseconds (ms) has been associated with a twofold to threefold higher risk for TdP, and each 10-ms increase contributes to approximately a 5% to 7% exponential increase in risk. QT prolongation can increase hospital length of stay and all-cause mortality in patients. In addition, many drugs have the potential to cause QT prolongation and/or TdP, either alone or in a drug interaction situation.

ECG Pointers: Is it Torsade de Pointes?

Torsade de pointes is a form of polymorphic ventricular tachycardia characterized by a gradual change in the amplitude of QRS complexes. It will appear as if there is “twisting” of the QRS complexes around the isoelectric line. Torsade is associated with a prolonged QT interval, which may be congenital or acquired (for example, due to medications, hypokalemia, or hypomagnesemia). Torsade usually terminates spontaneously but frequently recurs and may degenerate into ventricular fibrillation.

Long QT Syndrome with Continuously Recurrent Polymorphic VT: Management

Excellent review of management.

Long QT Syndromes and Torsade de Pointes

To diagnose LQTS, we should first know how long a QT interval is too long. Since the QT interval varies with heart rate, we must use the rate-corrected QT (QTc) interval calculated using the Bazett formula (QTc = QT/square root of the R-R interval in seconds). The latest American Heart Association/American College of Cardiology Foundation/Heart Rhythm Society Scientific Statement for interpretation of ECG in 2009 defines prolonged QT as follows: women, QTc lasts for 460 ms or longer men, QTc lasts longer than 450 ms.

Pharmacological treatment of acquired QT prolongation and torsades de pointes

It is now half a century since the French cardiologist François Dessertenne published his original report of a characteristic polymorphic ventricular tachycardia and coined the phrase ‘torsades de pointes’ (TdP) or ‘twisting of the points’ to describe its ECG appearance. This uncommon arrhythmia characteristically occurs in self-terminating bursts, causing dizziness or syncope and occasionally convulsions, but can occasionally degenerate into ventricular fibrillation, resulting in sudden cardiac death. TdP occurs when there is delayed ventricular repolarization with associated triggered activity due to early afterdepolarizations (EADs).

Prevention of Torsade de Pointes in Hospital Settings

Cardiac arrest due to torsade de pointes (TdP) in the acquired form of drug-induced long-QT syndrome (LQTS) is a rare but potentially catastrophic event in hospital settings. Administration of a QT-prolonging drug to a hospitalized population may be more likely to cause TdP than administration of the same drug to an outpatient population, because hospitalized patients often have other risk factors for a proarrhythmic response.

Resources

ERcast.Lite

Torsades de pointes is very bad. It easily degenerates into Ventricular Fibrillation (VF) and that’s sudden cardiac death. How many cases of torsades have you seen in your career? Are your ready for it when you see it?

Life in The Fastlane

Polymorphic ventricular tachycardia (PVT) is a form of ventricular tachycardia in which there are multiple ventricular foci with the resultant QRS complexes varying in amplitude, axis and duration. The commonest cause of PVT is myocardial ischaemia. Torsades de pointes (TdP) is a specific form of polymorphic ventricular tachycardia occurring in the context of QT prolongation; it has a characteristic morphology in which the QRS complexes “twist” around the isoelectric line. For TdP to be diagnosed, the patient has to have evidence of both PVT and QT prolongation.

Patient

Torsades de pointes is usually not sustained and terminates spontaneously but frequently recurs unless the underlying cause is corrected. Torsades de pointes may degenerate into sustained ventricular tachycardia or ventricular fibrillation. Torsades is a life-threatening arrhythmia and may present as sudden cardiac death in patients with structurally normal hearts.

StatPearls

Torsades de Pointes is a type of polymorphic ventricular tachycardia characterized by a gradual change in amplitude and twisting of the QRS complexes around an isoelectric line on the electrocardiogram. Torsades de Pointes is associated with QTc prolongation, which is the heart rate adjusted lengthening of the QT interval. A QTc is considered long when it is greater than 450 ms in males and 460 ms in females. A QTc greater than 500 ms has been associated with a two-fold to three-fold increase in risk for Torsades de Pointes. The rhythm may terminate spontaneously or may degenerate into ventricular fibrillation.