From the Guidelines
The management approach for patients presenting with low QRS voltage in chest leads should prioritize identifying and addressing the underlying cause, with a focus on conditions such as pericardial effusion, amyloidosis, and obesity, through comprehensive evaluation including echocardiography, chest X-ray, and laboratory studies as indicated by the European Society of Cardiology guidelines 1. The initial assessment for patients with low QRS voltage in chest leads involves a thorough history and physical examination to identify potential causes. Key considerations include:
- Pericardial effusion, which may require pericardiocentesis if hemodynamically significant
- Infiltrative cardiomyopathies, such as amyloidosis, which may necessitate disease-specific therapy, including further imaging like cardiac magnetic resonance (CMR) or technetium-99m 3-diphosphono-1,2-propanodicarboxylic acid (99mTc-DPD) scan, and potentially endomyocardial biopsy 1
- Obesity or chronic obstructive pulmonary disease (COPD), which may not require specific intervention for the low voltage itself but should be managed appropriately to reduce cardiovascular risk
- Other conditions like myocardial ischemia or infarction, which would require appropriate cardiac evaluation including echocardiography, troponins, and potentially coronary angiography 1 Given the potential for low QRS voltage to be associated with significant cardiac pathology, a comprehensive diagnostic approach is essential, guided by the clinical presentation and supplemented by diagnostic tests as needed, to ensure timely and appropriate management of underlying conditions. Monitoring for disease progression with serial ECGs and echocardiograms is crucial, with the frequency of follow-up determined by the underlying condition and its severity. The European Society of Cardiology guidelines provide a framework for the diagnosis and management of heart failure and related conditions, including those that may present with low QRS voltage, emphasizing the importance of a thorough and multidisciplinary approach to patient care 1.
From the Research
Management Approach for Low QRS Voltage in Chest Leads
The management approach for patients presenting with low QRS voltage in chest leads involves several considerations, including the underlying cause of the low voltage and the patient's overall clinical condition.
- Cardiac Tamponade and Pericardial Effusion: Low QRS voltage can be a feature of cardiac tamponade, but not of pericardial effusion per se 2. In patients with cardiac tamponade, pericardiocentesis or anti-inflammatory medication may help improve QRS voltage.
- Multi-vessel Disease: Low QRS voltage has been associated with multi-vessel disease in patients with anterior ST-segment elevation myocardial infarction 3. In these cases, coronary artery bypass grafting (CABG) may be necessary.
- Left Ventricular Hypertrophy: Low QRS voltage in limb leads can indicate accompanying precordial voltage attenuation, resulting in underestimation of left ventricular hypertrophy 4. Echocardiography may be necessary to accurately diagnose left ventricular hypertrophy in these patients.
- In-hospital Mortality: Low QRS voltage has been shown to be a predictor of in-hospital mortality in acutely ill medical patients 5. A combined lead I + II voltage <1.8 mV was significantly associated with in-hospital mortality.
- Cardiac Amyloidosis: Low QRS voltages are a common electrocardiographic feature in patients with cardiac amyloidosis, and have been shown to be independently associated with cardiovascular mortality 6.
Clinical Correlates and Prognostic Value
The clinical correlates and prognostic value of low QRS voltage vary depending on the underlying condition.
- In cardiac amyloidosis, low QRS voltages are more frequent in light chain amyloidosis (AL) than in transthyretin amyloidosis (ATTR) 6.
- In patients with anterior ST-segment elevation myocardial infarction, low QRS voltage is associated with multi-vessel disease and in-hospital CABG 3.
- In acutely ill medical patients, low QRS voltage is a predictor of in-hospital mortality, along with impaired mobility, National Early Warning Score, and male gender 5.