Nanobacteria-associated calcific aortic valve stenosis.

Calcific aortic valve stenosis is the most common valvular disease in developed countries, and the major reason for operative valve replacement. In the US, the current annual cost of this surgery is approximately 1 billion dollars. Despite increasing morbidity and mortality, little is known of the cellular basis of the calcifications, which occur in high-perfusion zones of the heart. The case is presented of a patient with calcific aortic valve stenosis and colonies of progressively mineralized nanobacteria in the fibrocalcific nodules of the aortic cusps, as revealed by transmission electron microscopy. Consistent with their outstanding bioadhesivity, nanobacteria might serve as causative agents in the development of calcific aortic valve stenosis.

Laser extraction of infected pacemaker and ICD leads: early experience at Charleston Area Medical Center.

Infection of pacing and cardioverter defibrillator (ICD) implants is associated with high morbidity and mortality. To report a single center experience of extracted leads, we analyzed 42 (11 ICDs and 31 pacemakers) that had been extracted using laser sheath technology at Charleston Area Medical Center between November 2000 and September 2003. The indications for extractions were infection in 48% of the patients (n = 13) and lead malfunction in 52% (n = 14). In the infection group, 6 patients presented with endocarditis and 7 with pocket erosion and/or infection. Mean patient age was 69.5 years (range 46-96) and mean duration of lead implantation was 68.3 months (range 4-149). Complications with lead extraction occurred in 15% (n = 4); 1 patient had bleeding from right subclavian vein (RSCV); 1 patient had right ventricle perforation; and 2 patients developed cardiac tamponade. One patient with tamponade died despite emergency surgery. During a follow up of at least 8 months (range 8-42), 19% (n = 5) and 7% (n = 2) deaths occurred in the lead malfunction and infection groups respectively. This study shows that extraction is effective in treating pacemaker or ICD infections, but with a significant complication rate.

Methadone-induced torsade de pointes in a patient with normal baseline QT interval.

Torsade de pointes (TdP) is a life threatening cardiac arrhythmia that is typically associated with prolongation of the QT interval. A wide variety of nonantiarrthymic medications may trigger TdP in patients with prolonged QT interval, only a few reports have described an association between TdP and methadone. We report a case of TdP caused by a large dose of methadone in a patient with presumably normal QT interval at baseline prior to his presentation at the hospital.

Nanobacteria-caused mitral valve calciphylaxis in a man with diabetic renal failure.

We have found that nanobacteria, recently discovered Gram-negative atypical bacteria, can cause local calciphylaxis on the mitral valve in a setting of high-calcium X phosphorous product in the blood. We present the case of a 33-year-old man with diabetic renal failure on continuous ambulatory peritoneal dialysis who died as a result of multiple brain infarcts due to embolizations from mitral valve vegetations. Systemic calciphylaxis was not present. Spectrometric analysis of the mitral valve vegetations showed that they were composed of calcium phosphate, carbonate apatite form, and fibrin. The electron microscopy of the thrombotic vegetation demonstrated nanobacterium as a nidus for carbonate apatite formation. Investigation for the presence of nanobacteria in the multiple organs involved in systemic calciphylaxis may be of help in elucidating the pathogenesis of this frequently fatal disorder.