Can pace and sense in one, two, or three chambers.

Two types of lead: unipolar or bipolar.

International codes: first letter, chamber paced (V = ventricle, A = atrium, D = dual); second letter, chamber sensed (V = ventricle, A = atrium, D = dual); third letter, how the device responds to the event (I = inhibits, T = triggers, D = dual, O = nothing). A fourth letter can be present to describe added features.

Ventricular lead placed most commonly in RV apex, RVOT, or on septum.

Atrial lead placed in the right atrial appendage.

Indications: (1) symptomatic complete heart block; (2) symptomatic second-degree heart block; (3) bifascicular block with intermittent third-degree block, second-degree block, or BBB; (4) trifascicular block with intermittent third-degree or second^–degree block; (5) symptomatic sinus node dysfunction; (6) symptomatic chronotropic incompetence; (7) carotid sinus hypersensitivity; (8) sustained VT caused by pauses; (9) drugs that result in symptomatic bradycardia.

Absolute contraindication to MR. In particular circumstance when the scan is vital the MR examination could be performed after accurate situation assessment under strictly monitorization.

New MR-compatible pacemaker is recently available.

Complication of bacterial endocarditis

The aortic valve ring is more frequently affected than the mitral valve.

MR: (1) heterogeneous low signal on T1w and high SI on T2w; (2) contrast enhancement; (3) cine images are helpful to detect the presence of communication between the abscess cavity and the cardiac chambers.

Techniques: echocardiography, SPECT, PET, MR, CT.

Pharmacological agents: (1) vasodilators (adenosine, dipyridamole, regadenoson); (2) beta-agonist (dobutamine).

Myocardial perfusion reserve: the ratio of regional myocardial blood flow after induced vasodilatation to that under resting conditions (cutoff value: 1.5).

CT perfusion: (1) dynamic acquisition, absolute quantitative assessment; (2) single-energy or dual-energy helical acquisition, semiquantitative assessment.

MR perfusion: (1) dynamic acquisition, absolute quantitative assessment.

Qualitative interpretation: presence of subendocardial or transmural hypointense rim during the “first pass” of contrast.

Semiquantitative interpretation: measurement of myocardial perfusion reserve.

Quantitative interpretation: measurements of regional myocardial blood flow (in ml/g/min) using time–intensity curve deconvolution with a measured arterial input function (usually from the left ventricular cavity or ascending aorta).

See also Adenosine, Dobutamine, Dipyridamole, and Regadenoson.

Most common location is right cardiophrenic angle (80 %).

CT/MR: (1) thin wall, without septa; (2) no contrast enhancement; (3) compression of adjacent structures.

Differential diagnosis: hydatid disease, extracardiac cyst, pericardial tumor.

Causes: (1) pericarditis; (2) cardiac failure; (3) malignancy; (4) uremia; (5) iatrogenous after percutaneous cardiac procedure.

Pericardial effusion is not specific for myocarditis but could represent a sign of acute inflammation.

MR: high sensitivity and allows individuation of effusion small as 30 ml.

See also Pericarditis, Acute.

Causes: lung, breast, melanoma, esophagus, leukemia, multiple myeloma, lymphoma, and thymoma.

CT/MR: (1) pericardial effusion; (2) irregular thickening or pericardial mass; (3) lesion contrast enhancement.

Common benign tumors: lipoma, teratoma, fibroma, hemangioma, lymphangioma, neurofibroma, paraganglioma, and granular cell myoblastoma.

Malignant tumors: pericardial metastasis (10–12 % of patients with malignancy), pericardial mesothelioma.

See also Pericardial Metastasis.

Acute inflammation of pericardium with or without pericardial effusion.

CT: (1) pericardial effusion (transudate, 0–25 HU; exudate, >25 HU); (2) pericardial thickening or irregularity of pericardial contour.

MR: (1) pericardial effusion (transudate: T1w hypointense and T2w hyperintense; exudate: T1w and T2w hyperintense); (2) pericardial edema; (3) pericardial and adjacent myocardium LE.

Complete: (1) heart displaced laterally and posteriorly; (2) dilated RV; (3) lung tissue interposition between base of the heart and diaphragm.

Partial: ventricular indentation.

Usually asymptomatic, but LV herniation is possible in partial absence with arrhythmias and chest pain.

Development of cardiac failure between the last month of pregnancy and 5 months postpartum in the absence of any identifiable cause or recognizable heart disease prior to the last month of pregnancy and LV systolic dysfunction.

Full recovery in 50 % of cases.

Lipid plaque: instable with higher risk of rupture.

Calcified plaque: stable.

CT: (1) predominantly lipid-rich plaques, ≤60 HU; (2) intermediate plaques, 61–119 HU; (3) predominantly calcific plaques, ≥120 HU.