Recanalization of Chronically Occluded Coronary Arteries: Single-Center Experience in 400 Cases, Including Long-Term Angiographic Follow-Up

The study presented comprises the initial and angiographic long-term results of a consecutive series of recanaliza-tion procedures in a single center. Between 1988 and 1992, a total of 400 patients underwent transluminal recanalization for total coronary occlusions. In 82% of successfully attempted patients, the occlusion could be passed by a standard guidewire. The overall initial success rate was 75% (298 of 400). The highest success rates could be achieved in the left circumflex artery (84%) and left anterior descending coronary artery (77%). Complications were uncomplicated myocardial infarction in ten patients (2.5%) and death in two patients (0.5%). Angiographic follow-up 3–6 months after recanalization could be achieved in 263 (88%) of 298 patients. Significant restenosis (≥ 50% minimum lumen diameter) was found in 57 (22%) of 263, and reocclusion was present in 38 (14%) of 263 patients, resulting in a total recurrence rate of 36%. In conclusion, recanalization can be performed with an initial success rate of 75% using bare-wire technique under the prerequisite operator experience. If a nearly complete angiographic follow-up is performed, the overall recurrence rate is 36%, which seems to be very acceptable in comparison with PTC A results for incomplete obstructions published so far . (J Interven Cardiol 1996;9:73–79)     

High Rate of Late Dislodgements of an Active Fixation Atrial Lead

Between May 1985 and May 1991 we implanted 115 DFH-leads as unipolar atrial leads. The active fixation mechanism of this electrode consists of two sickle-shaped anchoring hooks which are placed at a distance of 0.9 mm parallel to the distal flat end of the electrode. All leads were affixed to the free wall of the right atrium. One hundred eight leads (93.9%) were implanted for dual chamber pacing and seven leads (6.1%) for single chamber atrial pacing. Parameters measured at implantation were (mean values): stimulation threshold 1.06 ± 0.42 V at 0.5 msec pulse width, P wave amplitude 5.12 ± 2.04 mV, and lead impedance 560 ± 76.1 Ohms. Within the first week after implantation, three early dislodgements occurred (2.6%). The follow-up period averaged 30.4 ± 16.2 months (range 2–76 months). During this time, 14 late macrodislodgements (12.2%) occurred after a mean period of 18.4 months (range 2–59 months). All of them required reoperation. The active fixation mechanism of the DEH-lead appears to be unreliable, if implanted in the free wall of the right atrium for dual chamber pacing.     

Coarctation of the Aorta: Quantitative Analysis by Transesophageal Echocardiography

Transesophageal echocardiography and standard two-dimensional echocardiography were performed in 15 patients with suspected coarctation of the aorta. Aortic diameters and crosssectional areas were determined by means of TEE and compared with clinical findings and catheterization data. The isthmus of the aorta could be imaged in all patients using TEE, but in only seven patients using standard suprasternal echocardiography. Compared with controls, aortic diameters were narrowed in 9 of 15 patients, and cross-sectional areas were reduced in 13 of 15. There was a satisfactory correlation between TEE data and angiographic and hemodynamic data. TEE is a promising method of a diagnosing and quantifying coarctation of the aorta, and is more sensitive than conventional two-dimensional and Doppler echocardiography.     

Atrial Natriuretic Peptide Levels Reflect Hemodynamic Changes Under Pacemaker Stimulation

Pacemaker stimulation influences plasma levels of atrial natriuretic peptide (ANP). This study evaluated in individuals without impaired myocardial function whether a consecutive increase of pacing rates results in reduced alteration of plasma ANP levels mirroring a putative decrease of atrial contribution to cardiac output. In nine resting patients with DDD pacemakers, absolute and relative ANP plasma levels were determined under DDD (175 msec AV delay) and VVI pacing at a pacing rate of 72, 82, 92, and 113 beats/min. When pacing rates were consecutively increased, higher plasma ANP concentrations were measured. However, the differences in relative ANP levels were nearly identical. Therefore, it seems likely that the atrial contribution to cardiac output at high pacing rates is less important than at lower frequencies, at least when the overall myocardial function is not impaired.     

Social acceptance of smoking regulations in the workplace: A study from Southern Germany

Smoking regulations in the workplace are increasingly employedto protect non-smokers against passive smoking. Nevertheless,concern about their social acceptance hinders their implementationin many instances. Social acceptance of worksite smoking regulationswas assessed in a cross-sectional study, which was conductedin 1992 among 930 employees of a Southern German telephone company.A minority of 16.5% among employees who smoked felt discriminatedagainst. Perceived discrimination of smokers was strongly associatedwith the number of cigarettes smoked per day, but not with existingsmoking regulations. Most smokers (79.2%) and non-smokers (94.9%)were in favour of some type of smoking restrictions; proportionswere even higher in workplaces where smoking restrictions werealready in effect. Among current smokers, a preference for smokingrestrictions was positively associated with a desire to stopor reduce smoking. These results suggest that smoking regulationsin the workplace can be accepted by smokers and non-smokersand are perceived as an aid to stop or reduce smoking ratherthan a discriminating measure among current smokers.     

Human gastric mucosal adenylate cyclase activity: effects of various cytoprotective prostaglandins

Several prostaglandins prevent ulcer formation (called cytoprotection) by a mechanism other than inhibition of gastric acid secretion. One suggestion is that they increase cyclic AMP in non-parietal cells. A variety of prostaglandins with potent cytoprotective properties were tested for their capacity to modulate adenylate cyclase activity in homogenates of human gastric mucosa. Prostaglandin E2, prostacyclin (PGI2) and 15(S)-methyl-PGE2 stimulated the cyclase in human gastric mucosal biopsy specimens in a dose-dependent manner. Cytoprotective prostaglandins without antisecretory properties such as PGF2 beta were also able to activate the enzyme system dose-dependently. In contrast, cytoprotective prostaglandins such as PGD2, the PGE1-analogue, SC-29333, and the prostaglandin-like compound C83 did not stimulate human gastric adenylate cyclase. Whereas PGD2 did not modulate enzyme activity at all, SC-29333 and C83, at concentrations greater than 10 mumol/l, inhibited basal and PGE2-stimulated enzyme activities. These studies suggest that cyclic AMP is not directly related to the cytoprotective effect of prostaglandins, at least in human gastric mucosa.     

Interaction of laxatives with enzymes of cyclic AM P metabolism from human colonic mucosa

The mechanism by which laxatives such as dioctyl sodium sulfosuccinate and ricinoleic acid evoke colonic fluid secretion has been suggested to involve mucosal cyclic AMP. Ricinoleic acid and dioctyl sodium sulfosuccinate were tested for their capacity to modulate the key enzymes of cAMP-metabolism--adenylate cyclase and cAMP-phosphodiesterase--in human colonic mucosa. Both laxatives were ineffective stimuli of human colonic adenylate cyclase. In contrast to ricinoleic acid, dioctyl sodium sulfosuccinate was a competitive inhibitor of soluble cAMP-phosphodiesterase activity. These experiments suggest that the cathartic properties of dioctyl sodium sulfosuccinate in human colonic mucosa might be mediated by cyclic AMP via inhibition of soluble phosphodiesterase activity.     

IL-1 ALPHA-INDUCED EXPRESSION OF ICAM-1 ON CULTURED HYPERPROLIFERATIVE KERATINOCYTES: SUPPRESSION BY ANTIPSORIATIC DIMETHYL-FUMARATE

Background. In the psoriatic plaque both IL-1 dysregulation and ICAM-1 expression on keratinocytes have been previously described. Furthermore systemic administration of fumarates has been reported to be effective in psoriasis. We, therefore, studied the effect of dimethyl-fumarate ester (DMF) on the putative IL-1-induced ICAM-1 expression. Methods. Hyperproliferative human kertinocytes (HaCaT cell line) were incubated in 10 to 100 U/mL IL-1 alpha for 24 h with and without preincubation with 0.4–12.0 uM dmf. Expression of icam-1 was measured by a special ELISA-APAAP technique. Results. The exposure to 11-1 led to a significant dose-dependent induction of ICAM-1 expression of from 124 ± 17 to 194 ± 22% (control 100 ± 12%), while proliferation remained unaltered. Pretreatment with > 4 μM DMF resulted in a distinct suppression of ICAM-1 expression and a slight decrease in proliferation. Conclusions. The present results show that ICAMI-1 expression on hyperproliferative keratinocytes may be triggered by il-i alpha and serve as a molecular target for antipsoriatic DMF.