A historical perspective of pacemaker infections: 40-years single-centre experience.

AIMS: The approach to infected cardiac devices has changed during recent decades. Optimal treatment is still a matter of debate, especially in pacemaker-dependent patients. Therefore, we investigated the management and outcome of patients with pacemaker infections in a single centre over four decades. METHODS AND RESULTS: We conducted a retrospective analysis of 4212 patients and extracted those with pacemaker infections admitted to Rostock Heart Center between 1973 and 2012. One hundred and thirty-one consecutive patients (median age 69.6 ± 14.9 years) were admitted for device infections. Two-stage exchange was performed in 42 patients (32.8%). In 72 patients (55%), explantation and implantation on the contralateral side was performed simultaneously. In 17 cases the device was not replaced. Mean follow-up was 63 ± 81 months. Reinfection rate was 12.2%, which declined from 24% (1980s) to 2.6% (after 2000). Complete device removal (in 57.3%) reduced the risk for reinfection by 75% (P = 0.02), as well as increasing age (0.049% per year, P = 0.001). One-stage exchange increased the risk of reinfection six-fold (P = 0.021). Cultured bacteria after initiation of antibiotic therapy predicted a four-fold increase in risk of a recurrent infection (P = 0.01). CONCLUSION: Continuous assimilation of guidelines for pacemaker infection improved the outcome over time: complete extraction of the infected device seems to be highly desirable. A one-stage exchange increased the risk of recurrent device infection and should probably be avoided, but complete extraction seems to be more important than timing.

The 125th anniversary of the His bundle discovery.

In 1893, Wilhelm His Jr. was the first to describe the AV (atrioventricular) bundle of the vertebrate heart, which now bears his name. Moreover, prior to the turn of the century, W. His Jr. had proved the function of the AV bundle by transection experiments in animals, and had interpreted Adams Stokes disease as heart block due to pathological changes within the bundle. In this way, he was ahead of his time. While clinical interest was limited to the bundle as the location of an AV block in the first half of the 125 years, it has gained attractiveness since then as a target of diagnostic and therapeutic procedures. The introduction of His bundle electrography relaunched the interest in cardiac arrhythmias. Once the AV bundle could be localized clinically, its ablation, and in recent times its permanent stimulation, became options in the therapy of well-defined arrhythmia and conduction problems.

The earliest published electrocardiogram showing ventricular preexcitation.

When in 1930, Wolff, Parkinson, and White published what is today known as the WPW, or preexcitation syndrome, they, and subsequently others, found few comparable cases in the preceding literature. Among these the report of Cohn and Fraser, published in 1913, was the earliest. However, another even earlier documentation in a 1909 article by Hoffmann escaped notice till now. The ECG of a patient with paroxysmal tachycardia reveals a short PR interval and a delta-wave-induced widening of the QRS complex, even though the reproduced tachycardia was not preexcitation related. The interpretation of this poorly reproduced ECG can be confirmed by another and more detailed description of the patient in an electrocardiography textbook published in 1914 by the same author. Thus, the earliest publication of an ECG showing ventricular preexcitation now can be dated back to 1909. Moreover, the Hoffmann monograph contains two additional examples of the WPW syndrome not noticed until now. All three cases published by Hoffmann had their first ECG recordings in 1912 or earlier.