Causes of death and heart pathology in pacemaker or implantable cardioverter-def ibrillator patients who died in hospital.

UNLABELLED: 83 pacemaker (PM)/14 implantable cardioverter-defibrillator (ICD) autopsied patients, predominantly males, deceased 4.0±3.0/2.8±2.5 years after implantation in hospital. Coronary artery disease was most frequent. Its consequences were more severe in ICD patients. Sclerotic and rheumatic heart changes were present in older PM patients group only. The immediate cause of death was mostly of cardiac etiology. Relatively short implant-death interval should be explained by rather great part of non-cardiac causes of death in hospitalised patients. KEYWORDS: pacemakers - implantable cardioverter - defibrillators-causes of death - heart pathology - autopsy.

Histological findings around electrodes in pacemaker and implantable cardioverter-defibrillator patients: comparison of steroid-eluting and non-steroid-eluting electrodes.

AIMS: To analyse histological findings surrounding the electrodes in pacemaker/implantable cardioverter-defibrillator (PM/ICD) patients. To compare histology around steroid-eluting and non-steroid ventricular pacing electrodes. METHODS AND RESULTS: In autopsied PM/ICD patients histopathological findings around the electrodes were determined. Seventy patients were studied, PM(58), ICD(12), mean age 75.1 ± 9.3 years. The implantation-death interval was 4.0 ± 3.3 years. Most causes of death were cardiac (PM 52%, ICD 58%). The majority of atrial electrodes were attached to the endocardium and most ventricular electrodes were found in the myocardium (P ≤ 0.001). The maximum thickness of the fibrous electrode sheath was greatest for the ICD ventricular electrodes. Some electrodes were covered with fibrin thrombi and granulation tissue, most frequently in the ICD ventricular electrodes. The fibrous sheath usually contained chronic inflammatory cells and in some cases particles of foreign material, foreign body giant cells, and haematogenous pigment. The tissue around steroid-eluting ventricle PM electrodes was compared with the tissue around the non-steroid-eluting ventricle PM electrodes; granulation tissue, foreign material, giant cells being found more frequently around the steroid-eluting electrodes. The fibrous sheath was slightly thinner in the steroid-eluting electrodes. The histology around four coronary sinus electrodes was described. CONCLUSIONS: Atrial electrodes were attached more superficially to the endocardium while PM and ICD ventricular electrodes were more frequently embedded in the myocardium. The electrodes were covered by a connective tissue sheath as a result of thrombus organization. This process persisted most frequently around ICD ventricular electrodes. Only borderline differences were found between the histological findings around steroid-eluting and non-steroid-eluting PM ventricular electrodes.

Autopsy and clinical context in deceased patients with implanted pacemakers and defibrillators: intracardiac findings near their leads and electrodes.

AIMS: To evaluate intracardiac findings near leads and causes of death in pacemaker/defibrillator patients. METHODS AND RESULTS: Special autopsy was performed on 78 patients deceased in a hospital. Age at death was 77.9 +/- 10.0, implantation-death interval 4.0 +/- 3.3 years, ventricular leads n = 78, and atrial leads n = 21. Thrombi along leads in brachiocephalic vein/upper caval vein (BV/UCV) were found in 22 (7), in right atrium (RA) in 11 (8), and in right ventricle (RV) in 11 cases. Bipolar lead rings were fixed by fibrous tissue in 43 (4) cases. Connective tissue bridges and tunnels were found in BV/UCV in 44 (13), in RA in 17 (15), and in RV in 68 cases, with a length of 0.2-12.0 cm. Right ventricular leads in tricuspidal orifice were fixed by fibrous tissue in 11 and penetrating chordae in 25 cases. Main causes of death were: heart failure in 35, pulmonary embolism in 9, and myocardial infarction in 11 cases. CONCLUSION: We have found (i) thrombi on ventricular/atrial leads in 33/48%, (ii) bipolar lead rings fixed by fibrous tissue in 68/22%, (iii) connective tissue bridges or tunnels in ventricle/atrium in 87/71%, and (iv) ventricular leads fixed to valve or penetrating chordae in 46% of patients. We do recommend caution when extracting leads.