Case reports of pulmonary embolism following pacemaker implantation are rare.
One 1986 paper reported a "15% incidence of asymptomatic perfusion defects on V/Q lung scans". Forty patients were studied after PM implants. 20 were given low dose heparin and twenty were not. In the treatment arm there were 3 asymptomatic cases of high probability positive studies, normal ventilation,normal xray and decreased perfusion. In other words, the typical pattern of a pulmonary embolus on lung scan. So the number of 15% of silent PE post PM implantation is typically quoted in the literature on the basis of this single, small study .
A prospective study of 150 consecutive was published ,apparently a thesis at the University of Turku in Finland. There were five cases of PE. The abstract doesn't indicate if these were symptomatic or not.
My understanding is that routine post procedure anticoagulation is not widely done because of concern of pocket hematomas.
Full disclosure-my interests in this stems from having pulmonary emboli, clincally manifest six days after the implantation of a bi-ventricular pacemaker and after being treated for a pulmonary embolus with apixaban I developed a pacemaker pocket hematoma.
A physician can learn a great deal about a condition when he develops that condition.Talk about generating limbic valence.
One take home message I discovered was how variable radiologists' reading of CTPA
can be. A recent American Journal of Radiology article claimed that as many as 26% of CTPA are "false positive". In my case, the "official" reading indicated segmental emboli in the lingula and in the medial basal and anterior basal segments of the left lung.A second "unofficial" reading came from a friend, who is recently retired radiologist -no clots seen. Another unofficial done by a radiologist from the same institution as the EP cardiologist who was treating me and was read as showing some artifacts and "one or two emboli". Three radiologists produced three significantly different readings.