Embolism

An embolism is the lodging of an embolus, which may be a blood clot, fat globule, gas bubble or foreign material in the bloodstream. This can cause a blockage in a blood vessel. Such a blockage (vascular occlusion) may affect a part of the body distanced from the actual site of the embolism. This is in contrast to a thrombus, which causes a blockage at the site of origin.

Etymology

The word embolism comes from the Greek ἐμβολισμός, meaning "interposition".

Classification

There are different types of embolism, some of which are listed below.

Arterial or venous

Embolism can be classified as to where it enters the circulation either in arteries or in veins. Arterial embolism are those that follow and, if not dissolved on the way, lodge in a more distal part of the systemic circulation. Sometimes, multiple classifications apply; for instance a pulmonary embolism is classified as an arterial embolism as well, in the sense that the clot follows the pulmonary artery carrying deoxygenated blood away from the heart. However, pulmonary embolism is generally classified as a form of venous embolism, because the embolus forms in veins, e.g. deep vein thrombosis.

Intercalation (timekeeping)

Intercalation or embolism in timekeeping is the insertion of a leap day, week, or month into some calendar years to make the calendar follow the seasons or moon phases. Lunisolar calendars may require intercalations of both days and months.

Solar calendars

The solar or tropical year does not have a whole number of days (it is about 365.24 days), but a calendar year must have a whole number of days. The most common way to reconcile the two is to vary the number of days in the calendar year.

In solar calendars, this is done by adding to a common year of 365 days, an extra day ("leap day" or "intercalary day") about every four years, causing a leap year to have 366 days (Julian, Gregorian and Indian national calendars).

The Decree of Canopus, which was issued by the pharaoh Ptolemy III, Euergetes of Ancient Egypt in 239 BC, decreed a solar leap day system; an Egyptian leap year was not adopted until 25 BC, when the Roman Emperor Augustus successfully instituted a reformed Alexandrian calendar.

Embolism (liturgy)

The embolism in Christian Liturgy (from Greek ἐμβολισμός, an interpolation) is a short prayer said or sung after the Lord's Prayer. It functions "like a marginal gloss" upon the final petition of the Lord's Prayer (". . . deliver us from evil"), amplifying and elaborating on "the many implications" of that prayer. In the Roman Rite of Mass, the embolism is followed by the doxology or, in the Tridentine Mass (which does not have that doxology), by the Fraction.

According to the 1913 Catholic Encyclopedia, "[t]he embolism may date back to the first centuries, since, under various forms, it is found in all the Occidental and in a great many Oriental, particularly Syrian, Liturgies."

In the Roman Rite

In the Mass of the Roman Rite, as revised in 1969, the priest celebrant says or sings:

The English translation is:

A less literal English translation was used before 2011:

Older form

In the Tridentine form of the Roman Missal the embolism, said inaudibly by the priest except for the final phrase, "Per omnia sæcula sæculorum", is: