Transient sputum eosinophilia may occur over time in non‐eosinophilic asthma and this is not prevented by salmeterol

Background and Objective: Symptomatic, steroid‐naïve asthmatic patients may have low sputum eosinophil numbers. The aim of the study was to determine whether low sputum eosinophil numbers persisted over time, during treatment with salmeterol monotherapy. Methods: Forty steroid‐naïve, symptomatic asthmatic patients, with sputum eosinophils <3%, were randomized to receive open‐label salmeterol (50 µg twice a day, n = 30) or fluticasone (125 µg twice a day, n = 10) and were then assessed at 1, 3 and 6 months. All patients underwent spirometry, a methacholine challenge test and sputum induction at each visit. Symptom scores and peak expiratory flow were recorded throughout the study. Patients were permitted to withdraw from the study at any time, if they experienced exacerbations or deterioration of symptoms. Results: The average sputum eosinophil percentage remained normal (≤1.9%) in both groups over the study period. The eosinophil percentages were ≤1.9% in 65 of the 80 samples obtained from salmeterol‐treated patients throughout the study period. Eight patients had an asthma exacerbation or deterioration, during which one developed sputum eosinophilia. Twelve patients, 11 of whom were randomized to salmeterol and one to fluticasone, developed transient sputum eosinophilia at least once during the study. This was not associated with asthma exacerbation (except for one patient). Sputum neutrophil percentage did not change in either group. Conclusions: Low sputum eosinophil numbers persisted over 6 months in a majority of patients with non‐eosinophilic asthma who received salmeterol monotherapy. However, transient sputum eosinophilia occurred in 40% indicating that non‐eosinophilic asthma may not be a stable phenotype.     

Role of Epicardial Mapping in Catheter Ablation of Postmyocardial Infarction Ventricular Tachycardia

The role of epicardial mapping for radiofrequency (RF) catheter ablation of postmyocardial infarction monomorphic ventricular tachycardia (VT) is still under investigation. We present two septuagenarian patients with a history of myocardial infarction, poor left ventricular function, and drug-refractory monomorphic VT who were treated with RF catheter ablation. The first patient had a history of myocardial infarction, left ventricular aneurysm, and mitral valve replacement complicated by recurrent drug refractory VT and congestive heart failure. The second patient had ischemic cardiomyopathy and VT and was implanted with a cardioverter defibrillator and subsequently suffered repeated episodes of VT refractory to multiple antiarrhythmic drugs. In both patients, coronary sinus mapping was performed with a multipolar catheter as endocardial mapping did not reveal satisfactory sites for ablation. Epicardial catheter mapping provided stable electrograms and identification of areas of slow conduction during VT. RF lesions guided by epicardial mapping resulted in successful ablation of VT and no recurrence at long-term follow-up. This report emphasizes the potential usefulness of coronary sinus mapping as an adjuvant to endocardial mapping to guide VT ablation.     

Transcutaneous Cardiac Pacing for Termination of Tachyarrhythmias

ALTAMURA, G., ET AL.: Transcutaneous Cardiac Pacing for Termination of Tachyarrhythmias. Transcutaneous cardiac pacing (TCP) was used for interruption of tachyarrhythmias in 31 patients: 20 with ventricular tachycardia (VT); eight with atrioventricular reentrant tachycardia (AVRT) and three had atrioventricular nodal tachycardia (AVNT). The stimulators used (Pace Aid 50/52) allow pacing at programmable rates (50–160 ppm) and output (10–200 mA at 20-msec pulse duration), when possible overdrive pacing was used. Short bursts of stimuli were delivered with increasing current intensity until interruption of the arrhythmia or to the maximum energy tolerated by the patient. VTs were interrupted in eight of the 20 patients: four of the six (67%) treated by overdrive pacing and four of the 14 (29%) were treated by underdrive pacing. Supraventricular tachycardias (SVT) were terminated in eight of the 11 patients: seven out of eight (88%) AVT, and one out of three AVNT (33%). We observed two cases of arrhythmia worsening: a VT acceleration and induction of ventricular fibrillation in a patient with AVNT. TCP was well tolerated by the majority of the patients. We conclude that TCP is an effective method for interruption of ventricular and supraventricular reentrant tachycardias, but the risk of arrhythmia worsening must be considered.     

Sudden Death Due to Atrial Fibrillation in Hypertrophic Cardiomyopathy:

FAVALE, S., et al .: Sudden Death Due to Atrial Fibrillation in Hypertrophic Cardiomyopathy: A Predictable Event in a Young Patient. This case refers to a 39-year-old woman with hypertrophic cardiomyopathy (HCM) and family history of sudden death (SD). In 1985, high rate atrial stimulation induced VF. In 1996 an ICD was implanted and she remained without arrhythmic events until November 2000 when the device reported one episode of atrial fibrillation degenerating into VF and terminated by the ICD. The VF induction mechanism recorded by the ICD was similar to that observed in 1985. The high incidence of atrial tachyarrhythmias in HCM renders cases like this at higher risk of SD. The predictive role of incremental atrial stimulation merits highlighting in future studies. (PACE 2003; 26[Pt. I]:637–639)     

Cyclols,cyclodepsipeptides, and N-acyl-diketopiperazines from linear precursors: Synthesis and crystal structure of 10-membered cyclodepsipeptides

In order to investigate the relative formation tendency of different tautomeric ring systems (cyclols, cyclodepsipeptides and corresponding N -acyl-diketopiperazines), two linear peptide precursors containing proline as C -terminal residue, have been synthesized and subjected to cyclizing conditions. Boc-Ser-Phe-Pro-ONp (I) gave three isomeric cyclic compounds: Boc-Ser-Phe-Pro-(IV), N -(Boc-Ser)-cyclo -(Phe-d -Pro) (III) and the corresponding aza-cyclol (II). Starting from Hyb-Phe-Pro-ONp (V) two epimeric N (3-hydroxybutyryl)diketopiperazines (VI) and (VII) and the corresponding 10-membered cyclodepsipeptide (VIII) could be isolated. Crystal and molecular structure of VIII is reported. Crystals of VIII are orthorhombic, P2₁2₁2₁ with a = 9.684, b = 22.985, c = 7.841, z = 4. The two peptidic bonds are cis with ω values of 6.6° and — 18.1°, whereas the lactonic bond is of transoid type. The pyrrolidine ring has C₂—Cγ-exo conformation.     

Multiform Ventricular Ectopic Rhythm by Combined Parasystolic and Reentrant Activities

Multiform ventricular ectopic rhythm (MVER), i.e., at least two QRS configurations of ventricular ectopic beats (VEBs), was assessed by 24-hour ambulatory ECG recording in four patients with ventricular parasystole (VP). In two of these four patients, VEBs with fixed coupling to the preceding impulses coexisted with VP beats of different configuration. In case no. 1, the VEBs had an identical coupling interval to sinus bents and VP beats, suggesting a mechanism of reentry elicited from both dominant pacemakers. In case no. 2, an intermittent form of VP due to type II second-degree entrance block was present. In this patient, the VEBs were coupled to sinus beats and to sinus-VP fusion beats and appeared to be dependent on the sinus beats reaching the VP focus. A mechanism of reentry determined by the penetration of sinus beats into the VP area, with prematurity-dependent aberrancy of VEBs, was suggested for the coupled VEBs in this patient. These observations suggest that the coexistence of an automatic ventricular ectopic focus and of a reentrant activity determined by, or elicited from, an area of automaticity may constitute the underlying mechanism of MVER in some patients.     

Radiofrequency Catheter Ablation of the Slow Reentrant Pathway of Sustained Ventricular Tachycardia

The article reports the cases of two patients with severe coronary artery disease and associated recurrent sustained ventricular tachycardia successfully treated with radiofrequency catheter ablation. In the first patient, two different types of ventricular tachycardia (one incessant) were eliminated. In all procedures, an area of slow conduction critical for tachycardia maintenance was localized by endocardial mapping techniques. Radiofrequency energy delivered to this area could permanently modify the anatomical substrate of the arrhythmia. After single follow-ups of 19, 14, and 13 months regarding the arrhythmic entities, the patients are well and free from spontaneous recurrences.     

Effects of Hydrophilic and Lipophilic β-Blockers on Heart Rate Variability and Baroreflex Sensitivity in Normal Subjects

To evaluate the effect of a hydrophilic and a lipophilic β- blocker on the autonomic nervous system, 20 normal subjects were studied under baseline conditions and 7 days after being randomly assigned to metoprolol (200 mg/day), nadolol (80 mg/day), and placebo. Under each condition, the time-domain parameters were analyzed by means of 24-hour ECG monitoring and the frequency-domain parameters by means of the autoregressive method using 10-minute ECGs during rest, controlled respiration, and after a head-up tilt test. The alpha index (the gain in the relationship between the RR period and systolic arterial pressure variability) was also calculated. Both nadolol and metoprolol significantly increased all of the time-domain parameters except the standard deviation of the RR intervals; they also modified the frequency-domain parameters. Both blunted the significant reduction in the high frequency (HF) component and alpha index during tilt. In normal subjects, hydrophilic and lipophilic β-blockers similarly modify the time- and frequency-domain parameters that are particularly evident when high sympathetic tone is present (during daytime and tilt). The value of the alpha index was increased by both β-blockers in the HF, but not in the low frequency band; this difference might be due to the fact that the former is a measure of the vagal component of the baroreflex control and the latter a measure of the sympathethic component. The effects of hydrophilic and lipophilic β-blockers on the time- and frequency-domain parameters of heart rate variability are similar.