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An intracardiac foreign body was detected incidentally while the patient was having a pacemaker implanted. Even after necropsy its nature and mechanism of entry remained unclear.
A 78-year-old retired accountant sought advice because of recurrent blackouts. They had occurred over 49 years and happened every few months. Before an attack he would feel hot and start to sweat. He would lose consciousness for about 5 seconds and then rapidly return to normal. A year before, when he had a circumcision, the anaesthetists had noted an erratic pulse. He was found to have atrial fibrillation but 24 hour ambulatory electrocardiography showed no prolonged pauses and on echocardiography the heart seemed structurally normal. The initial diagnosis was of recurrent vasovagal attacks with more recent onset of atrial fibrillation. Blackouts continued, and one caused special concern because for two hours afterwards he was left with dysphasia and right facial paralysis. In addition to atrial fibrillation his electrocardiogram now showed left anterior hemiblock and right bundle branch block. In view of these new conduction abnormalities he was advised to have a pacemaker.
On his preoperative chest X-ray (Figure 1) and on screening for pacing he was found to have a linear, apparently metallic, needle-like structure with a gap in its centre. This was shown to lie in the left hemithorax and three weeks after successful pacing a CT scan confirmed that the foreign body lay in his heart. The patient was closely questioned about previous trauma. Neither he nor his wife could recall any traumatic experience. He had worked in Kenya during the Second World War and had not served in the Armed Forces. He gave permission for his heart to be examined when he died.
3 years later he was admitted with a gastrointestinal bleed due to a duodenal ulcer. Despite a laparotomy and underrunning of the bleeding ulcer he had a postoperative haematemesis and died. At necropsy the heart showed obvious gross concentric left ventricular hypertrophy, mild senile calcific aortic stenosis and moderate to severe coronary artery disease. A single-channel pacemaker wire was firmly adherent in the apex of the right ventricle (Figure 2). On the anterior surface of the heart just adjacent to the left anterior descending artery there was a short fibrous tag within which was a firm grey/black nodule. Dissection below this revealed a tract containing a straight rusty iron fragment 6 cm in length and less than 1 mm in diameter. There was extensive brown staining in the immediately surrounding tissue secondary to iron deposition. The metal came within 4 mm of the left anterior descending artery and was seen to run in the interventricular septum close to the right ventricular endocardium (Figure 3).
A sample of metal was retrieved and subjected to electron microscopic examination, which showed a thin metal core with surrounding rust. X-ray microanalysis revealed the presence of iron only. There was no evidence of material that could have been used for galvanizing and no other metallic elements were present that might have suggested a complex type of steel.
It remains quite unclear how this piece of iron entered the heart, but the fibrous tag presumably indicates a site of entry, so the most likely cause must be an unrecognized injury in the distant past, perhaps in childhood, rather than migration via the venous system from a distant site. In view of its position, the patient was fortunate not to have sustained damage to his left anterior descending coronary artery, but it seems possible that its site in the interventricular septum was responsible for the conduction abnormality which brought its presence to light.
We thank Dr R Moate, of the EM Unit, Faculty of Science, University of Plymouth, for performing the X-ray microanalysis.