Tachycardia – Fast Heart Rate

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When the heart beats for more than 100 beats per minute, this condition is called tachycardia. There is a shorter relaxation phase whenever the heart beats too quickly. This is usually caused by two primary problems: cardiac output is decreased because the ventricles are unable to fill completely or blood supply to the heart decreases because the coronary arteries receive less blood.

  • Tachycardia is defined as either stable or unstable.
  • When the heart reaches 150 beats per minute or more, other symptoms usually abound.
  • Keen attention is always required when dealing with unstable tachycardia.
  • Attention to stable tachycardia is still necessary, as this can quickly evolve into an unstable one.

Symptoms of Tachycardia

  • Hypotension
  • Sweating
  • Pulmonary edema/congestion
  • Jugular venous distension
  • Chest pain/discomfort
  • Shortness of breath
  • Weakness/dizziness/lightheadedness
  • Altered mental state

Symptomatic Tachycardia With Heart Rate > 100 BPM

1. Give immediate synchronized cardioversion if the patient is unstable.

  • Is the tachycardia experienced by the patient leading to instability or are other symptoms starting to show?
  • Are the symptoms (i.e., pain and distress of acute myocardial infarction (AMI)) producing the tachycardia?

2. Inspect the person’s hemodynamic status by administering IV, supplying supplementary oxygen and continually observing the heart.

  • Sinus tachycardia is often reflected by a heart rate of 100 to 130 BPM. When this happens, the goal is to determine and solve the root problem.
  • For heart rates greater than 150 BPM, it is likelier that this is just a symptom; the higher the heart rate, the likelier it is that the symptoms stem from tachycardia

3. Investigate the QRS Complex.

Treatment of stable patients can easily become hazardous, which is why it is strongly recommended for you to immediately seek professional help whenever you feel uncomfortable treating a stable patient.
Adenosine can lead to bronchospasm; therefore, adenosine should be administered with caution to patients suffering from asthma.

Regular Narrow Complex Tachycardia (Probable SVT)

  • Seek to perform vagal maneuvers.
  • Get 12-lead ECG; consider expert consultation.
  • Adenosine 6 mg rapid IVP; if no conversion, administer 12 mg IVP (second dose); may only attempt 12 mg once.

Irregular Narrow Complex Tachycardia (probable A-FIB)

  • Gain access to 12-lead ECG; consider consulting an expert.
  • Control rate with diltiazem 15 to 20 mg (0.25mg/kg) IV over two minutes or beta blockers.

Regular Wide Complex Tachycardia (Probable VT)

  • Gain access to 12-lead ECG; consider consulting an expert.
  • Convert rhythm amiodarone 150 mg IV over 10 minutes.
  • Perform elective cardioversion.

Irregular Wide Complex Tachycardia

  • Gain access to 12-lead ECG; consider consulting an expert.
  • Consider anti-arrhythmic.
  • If Torsades de Pointes, give magnesium sulfate 1 to 2 gm IV; may follow with 60 minutes.
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