8.7
Code 8.7 — Minnesota Code 8-7: sinus tachycardia. The rhythm starts normally in the sinus node, with every QRS preceded by a normal P wave, but the heart rate is above 100 beats per minute. In most cases sinus tachycardia is a normal response of the body to physical or emotional load, fever, pain or blood loss. It can also be a sign of an illness that needs treatment.
Causes
| Group | Examples |
|---|---|
| Physiological | Exercise, emotion, pain, pregnancy, infancy |
| Illnesses | Fever and infection, anaemia, dehydration, bleeding, hyperthyroidism, pulmonary embolism, heart failure, low blood sugar, low blood pressure |
| Substances | Caffeine, nicotine, alcohol and withdrawal, stimulants, salbutamol, decongestants, thyroid hormone excess |
| Special conditions | Inappropriate sinus tachycardia, postural orthostatic tachycardia syndrome (POTS) |
Clinical significance
Treatment is aimed at the cause, not at the heart rate itself. Persistent tachycardia at rest without an obvious reason should be investigated: blood count, thyroid function, inflammation markers and, if needed, echocardiography or Holter monitoring. A fast heart rate that starts and stops abruptly is more likely to be another arrhythmia, such as supraventricular tachycardia, than sinus tachycardia.
if a fast heartbeat comes with chest pain, breathlessness, fainting, confusion, high fever or signs of bleeding.
References
- Page RL, Joglar JA, Caldwell MA, et al. 2015 ACC/AHA/HRS guideline for the management of adult patients with supraventricular tachycardia. Circulation. 2016;133(14):e506–e574. doi:10.1161/CIR.0000000000000311
- Prineas RJ, Crow RS, Zhang ZM. The Minnesota Code Manual of Electrocardiographic Findings. 2nd ed. London: Springer; 2010. doi:10.1007/978-1-84882-778-3
This article is for general information and does not replace a consultation with a doctor. ECG findings must be interpreted by a physician together with symptoms and other tests.
Published on 14 May 2019