B P9 C86 Pericardial Diseases Flashcards
The pericardium is composed of two layers, the _____, a monolayer of mesothelial cells and collagen and elastin fibers adherent to the epicardial surface of the heart, and the _____, which is normally about 2 mm thick and surrounds most of the heart
Visceral pericardium
Fibrous parietal pericardium
The _____ pericardium is largely acellular and contains collagen and elastin fibers
Parietal
The _____ pericardium reflects back near the origins of the great vessels and is continuous with and forms the inner layer of the parietal pericardium.
Visceral
The pericardial space or sac is contained within these two layers, and normally contains up to _____ of serous fluid.
50 mL
While its removal has no obvious negative consequences, the pericardium does function:
(1) to maintain a relatively constant position of the heart in the thorax
(2) provides a barrier to infection
The best-characterized mechanical function of the pericardium is its _____. This reflects the mechanical properties of the parietal pericardium.
Restraining effect on cardiac volume
In developing regions where _____ is endemic, it is the most common cause of pericarditis and effusion.
TB
In developed countries, presumed _____ etiologies are most common
Viral and idiopathic
Idiopathic cases of acute pericarditis are presumed to be _____.
Viral
Cases of acute pericarditis with concomitant myocarditis with impaired function are labeled _____
Perimyocarditis
Cases of acute pericarditis with concomitant myocarditis with normal LV function are labeled _____
Myopericarditis
In greater than 90% of cases, the main symptom of acute pericarditis is _____, often quite severe
Chest pain
Classically, the pain of acute pericarditis radiates to the _____.
Trapezius ridge
The pathognomonic physical sign of acute pericarditis is the _____, reported in about one third of cases.
Friction rub
The classic rub consists of three components corresponding to _____, and can be likened to the sound made when walking on crunchy snow.
Ventricular systole
Early diastole
Atrial contraction
The _____ is a key test for diagnosing acute pericarditis
ECG
The classic finding in the ECG of patients with acute pericarditis is _____
Diffuse ST-segment elevation.
The ST-segment vector points leftward, anterior, and inferior, with ST-segment elevation in all leads except aVR and often V1
The distinction between acute pericarditis and transmural ischemia is usually not difficult because of _____.
(1) More extensive lead involvement
(2) Lack of evolution to pathologic Q waves in pericarditis
(3) More prominent reciprocal ST depression in ischemia
_____ is also common and considered the earliest ECG sign of acute pericarditis, reflecting pericardial involvement overlying the atria
PR-segment depression
Typical ECG evolution in acute pericarditis follows four stages: _____ The ECG often evolves without all four stages
(1) PR depression and/or diffuse ST segment elevation
(2) Normalization of ST segment
(3) T wave inversion with or without ST segment depression
(4) Normalization
In acute pericarditis, additional ECG changes that may constitute clues to the cause of pericarditis or associated findings include _____ in Lyme disease, _____signifying a previous, silent MI, and _____ pointing toward significant effusion.
Lyme disease: AV block
Previous /silent MI: Pathologic Q waves
Significant effusion: Low-voltage or electrical alternans
In acute pericarditis, CRP usually normalizes within _____
1 week and in almost all cases by 4 weeks after initial evaluation
In addition to aiding in diagnosis, ___ can be used to monitor disease activity and individualize duration of therapy
CRP
Because small to moderate effusions may not cause an abnormal cardiac silhouette, even modest cardiac enlargement is of concern and generally associated with an effusion greater than _____ mL.
300 mL