Amyloid cardiomyopathy: characterization by a distinctive voltage/mass relation

Area of Science:

• Cardiology
• Cardiovascular Imaging
• Cardiac Electrophysiology

Background:

• Systemic amyloidosis can infiltrate the myocardium, leading to cardiac amyloidosis.
• Noninvasive cardiac testing is crucial for diagnosing cardiac involvement.

Purpose of the Study:

• To assess the utility of noninvasive cardiac testing in diagnosing cardiac amyloidosis.
• To identify specific patterns indicative of cardiac amyloidosis using electrocardiography and echocardiography.

Main Methods:

• Evaluated 14 patients with biopsy-proven systemic amyloidosis using electrocardiography (ECG) and echocardiography.
• Compared findings with patients suffering from pericardial or aortic valve disease.
• Analyzed the relationship between electrocardiographic voltage and echocardiographic muscle cross-sectional area.

Main Results:

• Electrocardiography showed low voltage (SV1 + RV5/V6 = 14.6 +/- 4.8 mm), and echocardiography revealed increased muscle cross-sectional area (11.4 +/- 2.7 cm2/m2).
• Individual tests lacked specificity, but combining ECG and echocardiography revealed an inverse correlation (r = -0.79) between voltage and muscle area in amyloidosis patients.
• Abnormal left ventricular radius to wall thickness ratios were observed in symptomatic patients, suggesting myocardial infiltration.

Conclusions:

• Combining electrocardiography and echocardiography provides a distinctive diagnostic pattern for cardiac amyloidosis.
• The voltage/muscle area relationship is a key indicator, with derangements correlating with symptoms and mortality.
• Cardiac amyloidosis is characterized by myocardial infiltration, impacting left ventricular geometry.