Cardiac Tumors

Introduction

1. Thrombus or vegetations are the most likely etiology
2. Cardiac tumors are mostly secondary
3. Primary cardiac tumors are mostly benign

• Cardiac tumors are extremely rare (<0.1%)
• Found incidentally on cardiac imaging
• Characteristics
  • Echo contrast - malignant tumors are vascular, and hyper-enhance (thrombi do not)
    • Myxomas get partially enhanced
  • Attachment of a mass to an area of abnormal wall motion (typically akinesis or dyskinesis) = likely thrombus
  • Attachment to valve = more likely thrombotic (sterile) or vegetation (infectious)
• Consequences
  • Embolic Phenomena
    • L-sided --> more likely to embolize (i.e. myxoma)
    • Pulmonary embolization reported (esp with lymphomas)
  • Hemodynamic Consequences
    • Reduce cardiac output by obstructing inflow or valvular dysfunction

Types

Identified echocardiographically by:

• Location, imaging characteristics, clinical context

• Myxoma
  • Most common primary cardiac tumor
  • 70-80% in LA
  • Mid-portion of atrial septum by narrow stalk (15-20% in RA)
  • Heterogeneous mobile mass, two apperances:
    • Polypoid myxoma - larger, smooth surface, rough core.  Cystic lucencies (hemorrhage, necrosis)
      • Obstructs blood flow (HF symptoms)
    • Papillary Myxoma - larger, stretched apperance, multiple villi.
      • Embolic phenomena
  • Fever, weight loss, anemia, inflammatory markers. 
  • Management:
    • Surgical resection due to high risk of embolism. 
• Papillary Fibroelastoma
  • 3rd most common
  • Can arise from any endocardial surface
    • Commonly on valves (aortic and mitral)
    • Stippled borders (finger-like projections - "sea anemone")
    • Highly mobile stalk
  • Often multiple!!
  • High risk of embolism (either tumor itself embolizes or causes thrombus)
  • Can present as TIA/Stroke
  • Management:
    • Surgical excision if ≥ 1cm, left-sided, if good surgical candidate.
    • R-sided rarely need removal (unless huge)
• Lipoma
  • Adipose tissue
  • Broad based, immobile, without pedicle, well circumscribed.
  • Homogeneous (no calcification)
  • Can cause arrhythmias or valve dysfunction (most asymptomatic)
• Rhabdomyoma
  • Pediatric population
  • Ventricular free walls, (LV or septum) or AV valves.  
  • Small, well circumscribed (multiple), nodules or a pedunculated mass in cardiac cavity
  • Most regress spontaneously
  • Follow echocardiographically
  • Resection only if obstructing or arrhythmias.
• Fibroma
  • 2nd most common
  • Pediatric population
  • Distinct, well-demarcated, non-contractile, solid, highly echogenic mass (in myocardium)
    • Calcification possible
  • Locations:
    • LV free wall, anterior free wall, septum
  • Can extend into cavity, cause obstruction