Definition (Pediatr Infect Dis J 2006;25:165)
• Pericardium w/ 2 layers, outer (parietal) and inner (visceral) w/ small amount of fluid
• Pericarditis is inflammation of these layers; can be inflammation alone, inflammation w/ purulent, serosanguineous or hemorrhagic effusion +/− tamponade, and fibrosis +/− constriction
Pathophysiology (Pediatr Infect Dis J 2006;25:165)
• Inflammation of the pericardium results in pain and can result in fluid accumulation
• With purulent pericarditis, effusion can accumulate quickly resulting in right heart failure or tamponade; if develops slowly, greater amt of accum can be tolerated
• Tamponade = accumulated pericardial fluid compresses heart, prevents nml venous return on insp (↓ SBP and cardiac output w/ insp 2/2 ventricular interdependence w/ bowing of interventricular septum into LV impairing filling); “pulsus paradoxus”
Etiology: Multi-etiologies possible for pediatric pericarditis (Pediatr Infect Dis J 2006;25:165)
• Bacterial: Staph, Strep, Haemophilus, Neisseria, Tularemia, TB, Bartonella, Actinomyces, Nocardia, Salmonella, Coxiella
• Viral: Enteroviruses (coxsackie B), adenovirus, CMV, VZV, EBV, flu, HIV
• Parasites: E. histolytica and Echinococcus
• Fungi: Candida and Aspergillus
• Other infections: Spirochetes, Mycoplasma, Chlamydia, rickettsiae
• Noninfectious: Postsurgical, CTD, autoimmune, toxin mediated, Kawasaki
• Genetic/metabolic: Glycogen storage disease, hypothyroidism, FMF, uremia
• Cancer associated: Leukemia, metastatic or solid tumor, 2/2 chemo or XRT
• Trauma: Blunt or penetrating or iatrogenic/surgical
• Contemporary studies of mod to large pericardial effusions in ages 1 d–17.8 yr w/ neoplastic dz (39%), idiopathic (37%), collagen vascular dz (9%), renal dz (8%), bacterial infection (3%), HIV (2%) (Pediatr Cardiol 2007;29:90)
Diagnosis (Pediatr Infect Dis J 2006;25:165)
• EKG w/ diffuse ST elevation in all vascular distributions and PR depression in all but aVR, PR elevation in aVR most sens, QRSs +/− low voltage, electrical alternans, if effusion
• Eval of etiology includes CBC w/ diff, electrolytes w/ BUN/Cr, cardiac enzymes, viral assays, blood cx, & possibly evaluation for CTD, autoimmunity, or malignancy
• CXR +/− “globular” cardiac enlargement on PA film; huge heart but nml pulm vasc
• Echo is gold std for eval; cannot determine kind of fluid (hemorrhagic, infectious, etc.)
• Constrictive pericarditis: Assessment by echo limited, usually dx made by cath
• CT and MRI can both evaluate pericardium but echo is sufficiently sens and spec
• Pericardiocentesis if tamponade or suspected bact infxn; diagnostic in pts w/ unknown etiology (cell count, diff, cx, along w/ AFB, fungal & viral cx, viral PCR, cytology)
• Acute mgmt of tamponade is VOLUME resuscitation while arranging pericardiocentesis
• Assessment of tamponade via pulsus paradoxus; measure diff btw SBP at which Korotkoff sounds 1st audible (at 1st audible only w/ expiration) & pressure at which audible throughout full resp cycle; >10 mm Hg is a +pulsus (JAMA 2007;297:1810)
Treatment (Eur Heart J 2004;25:587)
• Management depends on type and underlying etiology of pericarditis
• Pain management and treatment of inflammation with NSAIDs, theoretical risk of hemorrhagic conversion exists but not established
• Colchicine demonstrated to be effective in adult trials, not approved in peds
• Acutely, steroids only for pts recalcitrant to NSAIDs or pts w/ acute pericarditis 2/2 connective tissue disease, autoimmune pericarditis or uremic pericarditis
• Purulent pericarditis w/ severe inflam resp may benefit from 1–2 wk steroids, as may TB pericarditis both acutely & chronically (Pediatr Infect Dis J 2006;25:165)
• Pericardiocentesis indicated in tamponade physiology, or if purulent, tuberculous, or malignant effusion suspected
Complications
• Fibrosis and constrictive pericarditis can occur 2/2 purulent pericarditis resulting in heart failure w/ a small rather than large globular appearing heart