Torsades de Pointes

Vijayalakshmi G

Non Critical Ward Incharge, Kauvery Heartcity, Trichy, India

*Correspondence:nursing.heartcity@kauveryhospital.com

Foreword

We nurses at Heart City see Ventricular Tachycardia very often, which provoked interest in Torsades de Pointes.

Background

Torsades de pointes is a type of very fast heart rhythm (tachycardia) that begins in the ventricles.

It is a type of polymorphic ventricular tachycardia which can occur in patients with a long QT interval.

Unlike a normal pulse rate 60-100 beats a minute, ventricular tachycardia is more than 100 beats a minute. Torsades de pointes can present with a heartrate anywhere between 150 to 300 beats a minute.

People who have long QT interval (seen on the ECG), an electrical conduction delay in the heart, tend to get torsades de pointes.

It can be life-threatening condition.

Symptoms

  1. Dizziness
  2. Palpitation
  3. Light headedness
  4. Syncope
  5. Cardiac arrest
  6. Sudden death

Causes

Some people are born with long QT syndrome, which may lead to Torsades de pointes.

Some medicines can cause Torsades de pointes:

  1. Antifungal
  2. Antibiotics
  3. Antipsychotics
  4. Antiemetic
  5. Antiarrhythmic
  6. Cancer medicines

Risk factors

  1. Having long QT syndrome(congenital)
  2. Having heart disease (Acute MI)
  3. Being a woman
  4. Being older than 65
  5. Taking diuretics
  6. Having profound bradycardia (very slow heartrate)
  7. Having low levels of calcium, magnesium or potassium
  8. Having excessive diarrhea and vomiting
  9. Acute kidney injury, liver failure

Complications

    1. Ventricular fibrillation
    2. Syncope
    3. Sudden cardiac death

Tests to diagnose long QT interval include:

  1. Electrocardiogram
  2. Blood tests to check electrolyte levels
  3. Echocardiogram
  4. Heart monitor

ECG:

Heart-monitor

Fig. 1. Torsade de pointes, an uncommon and distinctive form of polymorphic ventricular tachycardia (VT), characterized by a gradual change in the amplitude and twisting of the QRS complexes around the isoelectric line.

Medications

  1. Inj. Magnesium sulphate
  2. Isoprenaline (Beta 1-adrenergic agonists)
  3. Beta blockers (propronolol)
  4. Verapamil

Medical devices

  1. Implantable cardioverter defibrillator (ICD)
  2. Electrical cardioversion
  3. Defibrillation
  4. Temporary or permanent pacemaker

Prognosis

In congenital long QT syndrome, the mortality rate for untreated patients is 50% in 10 years, which can be reduced to 3-4% with therapeutic intervention.

In acquired long QT syndrome, the prognosis is excellent once the inciting factor has been identified and reliably withheld.

Patient education

Instruct patients to use medications only with the approval of a physician.

Instruct patients to avoid competitive sports (in cases of congenital long QT syndrome).

Close follow-up is needed because of a risk of sudden cardiac death. Offer emotional support; suggest attending a cardiac support group.

Patients should be taught how to monitor their pulse and recognize adverse drug effects. Families should undergo training for basic life support.

References

Jatin Dave, Torsade de Pointes, https://emedicine.medscape.com/article/1950863-overview, Updated: May 06, 2022

Vijayalakshmi

Ms. Vijayalakshmi

Non Critical Ward Incharge

Kauvery Hospital