Low QRS voltage

WikiDoc Resources for Low QRS voltage
Articles
Most recent articles on Low QRS voltage Most cited articles on Low QRS voltage Review articles on Low QRS voltage Articles on Low QRS voltage in N Eng J Med, Lancet, BMJ
Media
Powerpoint slides on Low QRS voltage Images of Low QRS voltage Photos of Low QRS voltage Podcasts & MP3s on Low QRS voltage Videos on Low QRS voltage
Evidence Based Medicine
Cochrane Collaboration on Low QRS voltage Bandolier on Low QRS voltage TRIP on Low QRS voltage
Clinical Trials
Ongoing Trials on Low QRS voltage at Clinical Trials.gov Trial results on Low QRS voltage Clinical Trials on Low QRS voltage at Google
Guidelines / Policies / Govt
US National Guidelines Clearinghouse on Low QRS voltage NICE Guidance on Low QRS voltage NHS PRODIGY Guidance FDA on Low QRS voltage CDC on Low QRS voltage
Books
Books on Low QRS voltage
News
Low QRS voltage in the news Be alerted to news on Low QRS voltage News trends on Low QRS voltage
Commentary
Blogs on Low QRS voltage
Definitions
Definitions of Low QRS voltage
Patient Resources / Community
Patient resources on Low QRS voltage Discussion groups on Low QRS voltage Patient Handouts on Low QRS voltage Directions to Hospitals Treating Low QRS voltage Risk calculators and risk factors for Low QRS voltage
Healthcare Provider Resources
Symptoms of Low QRS voltage Causes & Risk Factors for Low QRS voltage Diagnostic studies for Low QRS voltage Treatment of Low QRS voltage
Continuing Medical Education (CME)
CME Programs on Low QRS voltage
International
Low QRS voltage en Espanol Low QRS voltage en Francais
Business
Low QRS voltage in the Marketplace Patents on Low QRS voltage
Experimental / Informatics
List of terms related to Low QRS voltage

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Synonyms and keywords: low volts; low voltage;

Definitions of Low QRS Voltage:

• If the total amplitude above and below the isoelectric line is < 5 mm in all 3 standard leads.
• An average voltage in the limb leads of < 5 mm with an average of < 10 mm in the chest leads.
• Should be at least 5 mm in V₁ and V₆ , 7 mm in V₂ and V₅ and 9 mm in V₃ and V₄.

Pathophysiology of Low QRS Voltage

Three general processes contribute to low QRS voltage:

1. Damping of the electrical signal due to excess air (emphysema, COPD), fluid (pericardial effusion, pericardial constriction, pleural effusion), edema (anasarca), fat (obesity), physiologic variant, or amyloid cardiomyopathy
2. Electrically inert myocardium due to a loss of viable myocardium such as in myocardial infarction and Chagas disease]]
3. Infiltration of the myocardium (myxedematous, Chagas disease)

Causes of Low QRS Voltage

The presence of low voltage on the EKG should prompt an evaluation to rule out life threatening emergencies such as cardiac tamponade or a large pericardial effusion. These two diagnoses are suggested by the presence of tachycardia and electrical alternans along with the low QRS voltage. In alphabetical order the differential diagnosis includes:

• Alcoholic cardiomyopathy
• Amyloidosis
• Anasarca
• Dilated cardiomyopathy
• Beriberi heart disease
• Cardiomyopathy
• Chagas disease
• Diffuse coronary artery disease
• Congestive heart failure
• Constrictive pericarditis
• COPD
• Dilated cardiomyopathy
• Generalized edema and pedal edema
• Emphysema
• Hemochromatosis
• Hypothermia
• Hypothyroidism
• Ischemic cardiomyopathy
• Prior myocardial infarction
• Myocarditis
• Myxedema
• Obesity
• Pericardial effusion
• Pneumothorax
• Rejection after heart transplantation
• Restrictive cardiomyopathy
• Sarcoidosis
• Scleroderma
• Tamponade
• Technical error in the settings on the ECG apparatus (sensitivity should be at 10 mm/mV)

Electrocardiographic Examples

Low voltage QRS <10mm precordial