radiation-induced heart disease

Epidemiology

• increased likelihood with 3600-4000 Gy of cardiac radiation

Pathology

• myocardial fibrosis
  • microvascular ischemia at the level of myocardial capillaries
  • diastolic dysfunction is common
• effusive pericarditis
  • most commonly during 1st 6 months after radiation
  • generally asymptomatic
  • appearance may be delayed for years
• constrictive pericarditis
• radiation induced valvular heart disease
• cardiac conduction system disease
• radiation-induced coronary artery disease (CAD)
  • distinct from atherosclerotic CAD
  • tendency to involve osteal & proximal coronary arteries
  • greater extent of intimal fibrosis & adventitial thickening

Clinical manifestations

• effusive pericarditis
  • generally asymptomatic
  • occasionally patients complain of exertional dyspnea
• occult constrictive pericarditis
  • unexplained exertional dyspnea
  • occurs several years after radiation
  • jugular venous distention may be noted
  • no edema
  • no pericardial knock
• symptoms associated with constrictive pericarditis

Management

• increased likelihood of atherosclerosis
• friability of internal mammary artery when used as a bypass conduit for CABG
• constrictive pericarditis
  • seldom need pericardiectomy
  • symptoms generally controlled with diuretics
• no established guidelines for long-term follow-up

More general terms

• heart disease (cardiac disease)
• radiation injury; radiation toxicity

Additional terms

• pericarditis
• radiation therapy (XRT)