Tachycardia

Original Editor - Lucinda hampton

Top Contributors - Lucinda hampton and Tolulope Adeniji  

Introduction

ECG showing sinus tachycardia, 132 bpm

Sinus tachycardia is a regular cardiac rhythm in which the heart beats faster than normal. While it is common to have tachycardia as a physiological response to exercise or stress, it causes concern when it occurs at rest.

The normal resting heart rate for adults is between 60 and 100, which varies based on the level of fitness or the presence of medical comorbidities. Sometimes tachycardia signifies a health problem and could be the earliest sign of serious pathology. Thus, it is crucial to rapidly identify the underlying cause of tachycardia and determine if it indicates urgent evaluation and/or treatment. .

In some cases, tachycardia may cause no symptoms or complications. However if left untreated, tachycardia can disrupt normal heart function and lead to serious complications, including:

• Heart failure
• Stroke
• Sudden cardiac arrest or death.

Signs and Symptoms

Heart rate check

Tachycardia may cause no symptoms or complications. Signs and symptoms that may present include

• Shortness of breath and lightheadedness.
• Chest pain.
• A rapid, irregular pulse felt on the wrist or side of the neck.
• Uncomfortable and rapid heart palpitations felt in the chest.

Etiologies

Tachycardia can have physiological or pathological causes. Physiologically it is commonly associated with catecholaminergic triggers ,eg exercise, stress, pain, and anxiety. Pathologically, there are cardiac and non-cardiac etiologies, see below

Cardiac Etiologies

Include:

• Supraventricular (above the ventricle): where problems with the electrical signals in the atria of the heart cause the heart to beat faster, reducing blood flow to the rest of the body as the heart can't pump blood as effectively. eg atrial flutter and atrial fibrillation.
• Ventricular tachycardia: where the electrical signals in the ventricles of the heart cause the heart to beat faster affecting its ability to pump blood to the rest of the body.
• Acute coronary syndrome
• Torsades de pointes
• Myocarditis is an inflammatory process involving cardiac myocytes that is generally secondary to a viral infection.
• Cardiac tamponade is a collection of symptoms (traditionally hypotension, jugular venous distention, muffled heart sounds, pulses paradoxus, and interventricular septum bowing during inspiration) secondary to increased pressure in the pericardial space

Other Etiologies

Include:

1. Respiratory: Pulmonary Emboli; Hypoxia.
2. Gastrointestinal/Renal/Electrolyte: Hypoglycemia; Dehydration; Hyperkalemia; Hypomagnesemia.
3. Infectious Disease: Sepsis is a systemic inflammatory illness secondary to an infection that causes organ dysfunction
4. Vascular: Shock is an acute circulatory failure that provides insufficient tissue perfusion and hypoxia.
5. Hematologic: Hemorrhage is the disease process where a clinically significant amount of blood is lost after a blood vessel is damaged; Anemia
6. Toxicology: Ingestion of medications can cause tachycardia; Withdrawal from substances or medications is an additional source of tachycardia.
7. Sinus tachycardia; where the natural pacemaker in the heart sends electrical signals faster than normal. This can be in response to a stressor, or it can be a sign of eg anaemia, problems with the thyroid gland or general ill health.

Physiotherapy

Treadmill walk

Exercise is an important part of a healthy lifestyle, and it should not be avoided, even in clients who have a heart condition. For the vast majority of people with arrhythmias eg atrial fibrillation and tachycardia, exercise is encouraged. Exercise helps to strengthen the cardiovascular system and has a protective function against tachycardias

• Before starting exercise Cardiopulmonary Exercise Testing may be appropriate.
• Once client is cleaared by Cardiologist to commence exercise, stress importance of a slow start and and build up over time. If you client feels symptoms eg dizziness, palpitations or chest pain it is important to seek medical assistance immediately.
• Over time, client will understand how their body responds to certain exercise modalities and intensities, and you can adjust your exercise accordingly.
• Enrolling client into Cardiac Rehabilitation is a great option.
• See also Physical Activity and Cardiovascular Disease and Physical Activity and Exercise Prescription