Statin use in patients with an ICD was associated with a reduction in the risk of cardiac death or VT/VF, whichever occurred first, and was associated with a reduction in VT/VF episodes. These findings suggest that statins have anti-arrhythmic properties.

The concentrations of acetone, isoprene, and pentane in alveolar breath were examined in 50 smokers and 50 nonsmokers by gas chromatography. The baseline pentane in smokers was 0.17 +/- 0.03 nmol/L (mean +/- SE), which was not different from pentane in nonsmokers (0.23 +/- 0.03 nmol/L). There were also no differences between smokers and nonsmokers in the concentrations of acetone and isoprene. Serial breath samples were obtained from 15 smokers before smoking and at 5, 15, and 60 min after smoking. Although acetone was not altered by smoking, isoprene increased by 86% +/- 26% 5 min after smoking (P <0.001) and returned to baseline 10 min later. Pentane increased by 456% +/- 156% 5 min after smoking (P <0.001) and remained increased 10 min later (204% +/- 73% of baseline, P <0.05). Isoprene concentrations in mainstream cigarette smoke were >5000 times greater than breath concentrations, whereas pentane could not be detected in mainstream smoke. Because pentane is produced from the peroxidation of n-6 polyunsaturated fatty acids, the results provide evidence that cigarette smoking causes an immediate increase in lipid peroxidation.

Controversy continues regarding the precise nature of the reentrant circuit of AV nodal reentrant tachycardia, especially the existence of an upper common pathway. In this case report, we show that marked variation and irregularity in atrial activation (maximum AA interval variation of 80 msec) can exist with fixed and constant activation of the His bundle and ventricles during AV nodal reentrant tachycardia in a 45‐year‐old female patient. We propose that irregular atrial activation is due to variable and inconsistent conduction from the AV node to the atria through the perinodal transitional cell envelope extrinsic to the reentrant circuit. Our observations support the concept of an upper common pathway, at least in some patients with AV nodal reentrant tachycardia. (J Cardiovasc Electrophysiol, Vol. 14, pp. 309‐313, March 2003)

A unique form of ventricular tachycardia is described. The QRS complex morphology on the 12-lead ECG during tachycardia was grossly similar to that during sinus rhythm. The His bundle activation was passive and occurred with a long activation time from the ventricle to the His bundle. Although it mimics usual bundle branch reentry, this form of ventricular tachycardia appears to be due to a different mechanism in which the His bundle is not obligatory for the continuation of the reentrant phenomenon.

We describe the case of a patient who has a right atrial tachycardia and atrial fibrillation who was found to have a single site responsible for both. We recorded a tachycardia from this site with exit block into the remainder of the atria.