How Is Arrhythmia Diagnosed?
Cardiac arrhythmias often have symptoms that prompt patients to seek medical attention. Others have silent pathology that is discovered incidentally on a routine physical exam (and the risk-associated extra testing that is assigned as part of routine health management, e.g., blood tests, ECG, etc.).
Symptoms of palpitations and/or syncope (fainting/passing out) and near-syncope (dizziness/light-headedness) prompt diagnostics that can lead to prevention of cardiac events. Alternately, any incidental findings can prompt the same work-up as part of normal health maintenance.
History and Physical Exam
A medical history and family history are the first steps in diagnosing overt and covert warning signals. Diabetes, hypertension, smoking, dyslipidemia (elevated cholesterol/triglycerides), and any previous cardiac history will set a patient apart for extra testing. Chest pain is always significant until proven otherwise.
- A medication history can isolate signs and symptoms of arrhythmias due to side effects of certain drugs used for non-cardiac purposes or even for arrhythmias themselves
- Close relatives with a history of arrhythmia, sudden or unexplained death, or who have required the insertion of pacemakers or defibrillators will also spotlight those at risk
- The physical exam relies on vital signs, examination for arterial pulse rate and (jugular vein) pulsations, blood pressure, as well as the appearance of pallor or diaphoresis that can prompt cardiac diagnostics Auscultation of the heart is an essential component to discern extra heart sounds and murmurs, unusual pauses or separations between heart sounds, or irregularity of contractions (pulse)
Blood tests can identify biomarkers that identify myocardial infarction, but this is has the disadvantage of identification only after-the-fact.
ECG and Other Monitoring Modalities
The 12-lead electrocardiograph is the standard way to identify cardiac disease, ischemia, and arrhythmias. Although it is unsurpassed in getting a true, sweeping picture of the heart’s electrical activity over 360°, it can be limited by its brief 10-second snapshots of cardiac activity.For those with covert, intermittent, or very fleeting cardiac events and arrhythmias, long-term monitoring is accomplished by using a Holter monitor for 24-48 hours, 2-week surveillance using a Zio pad, or even years of monitoring using an implanted loop recorder with wireless technology to stream data on a daily basis to a patient’s doctor.
Problematic arrhythmias that can be diagnosed with the above diagnostics include:
- Atrial premature beats
- Ventricular premature beats
- Bradycardia (sinus bradycardia and “sick sinus” syndrome)
- Ventricular tachycardia
- Supraventricular tachycardia
- Dysrhythmia from atrioventricular block
- Atrial fibrillation