From the Guidelines
Bradycardia symptoms include fatigue, dizziness, lightheadedness, fainting or near-fainting spells, shortness of breath, chest pain, confusion, difficulty exercising, and weakness, as noted in the 2019 ACC/AHA/HRS guideline on the evaluation and management of patients with bradycardia and cardiac conduction delay 1.
Symptoms of Bradycardia
The symptoms of bradycardia can vary widely from insidious symptoms to episodes of frank syncope, and can be broadly classified into two general categories: sinoatrial node dysfunction (SND) and atrioventricular block.
- Fatigue
- Dizziness
- Lightheadedness
- Fainting or near-fainting spells
- Shortness of breath
- Chest pain
- Confusion
- Difficulty exercising
- Weakness Some people may experience palpitations or the sensation of missed or irregular heartbeats.
Severity of Symptoms
The severity of symptoms often correlates with how slow the heart rate is and whether underlying heart conditions exist. If you experience these symptoms, especially fainting or severe dizziness, seek medical attention promptly as untreated severe bradycardia can lead to complications including heart failure, sudden cardiac arrest, or other serious conditions 1. Many individuals with mild bradycardia may not experience any symptoms, particularly athletes whose slower heart rates are normal adaptations. Symptoms typically become noticeable when the heart rate drops significantly or when the body requires increased cardiac output, such as during physical activity. The clinical manifestations of bradycardia can be explained by the disparate electrophysiologic manifestations, ventricular rates, transience of these abnormalities, overall medical conditions, and medications 1. The term “symptomatic bradycardia” is used to denote a documented bradyarrhythmia that is directly responsible for development of the clinical manifestations of syncope or presyncope, transient dizziness or lightheadedness, heart failure symptoms, or confusional states resulting from cerebral hypoperfusion attributable to slow heart rate 1.
From the Research
Symptoms of Bradycardia
The symptoms of bradycardia can vary, but common symptoms include:
- Syncope (fainting) 2, 3
- Dizziness 2
- Chest pain 2
- Dyspnea (shortness of breath) 2
- Fatigue 2
- Asystole (a condition where the heart stops beating) 4, 5
Diagnosis and Treatment
Diagnosis of bradycardia-induced symptoms can be made through a combination of:
- Medical history 3
- ECG (electrocardiogram) 3
- 24-hour Holter monitoring 3
- Event-recorder 3 Treatment for symptomatic bradycardia may include:
- Atropine administration 2, 4, 5
- Isoproterenol administration 6
- Pacemaker implantation 2, 3, 6, 5
- Theophylline administration 5
- Aminophylline administration 4
Special Considerations
In certain cases, such as high cervical spinal cord injury, bradycardia can be a significant complication 4, 5. In these cases, treatment may need to be tailored to the individual's specific needs. Additionally, in patients with asymptomatic sinus bradycardia, evaluation of chronotropic reserve using atropine and isoproterenol tests can help identify those who may require preventive pacemaker implantation 6.