Nephropathy induced by contrast medium may be less likely to develop in high-risk patients when iodixanol is used rather than a low-osmolar, nonionic contrast medium.

No abstract

Objective. To investigate individual variations of platelet inhibition after clopidogrel-loading doses. Setting. Department of Cardiology, Linköping University Hospital, Linköping, Sweden. Subjects. Individuals with stable angina pectoris (n ¼ 18) subject to percutaneous coronary interventions (PCI) and subsequent stenting were investigated. Methods and experimental protocol. A 300-mg clopidogrel loading dose was administrated immediately after stenting (day 1) followed by an additional 75 mg clopidogrel after 24 h (day 2). The ADP-evoked platelet fibrinogen binding was analysed to estimate platelet reactivity immediately before angiography and on day 2. A flow cytometry technique was used with two ADP solutions (final concentrations 0.6 and 1.7 lmol L )1 ) employed as platelet activating agents. Soluble P-selectin was used as a marker of platelet activity.Results. When using 1.7 lmol L )1 ADP to activate platelets four individuals had a strong inhibition (i.e. platelet reactivity <10% of the day 1-value day 2).In contrast, five patients demonstrated a weak inhibition (i.e. platelet reactivity >60% of the day 1-value day 2). Similar results were obtained when using 0.6 lmol L )1 ADP as a platelet-activating agent. Clopidogrel, however, fails to suppress platelet activity as estimated from soluble P-selectin.Conclusions. Clopidogrel evoked platelet inhibition exhibits a considerable individual heterogeneity. Some individuals only had weak responses whereas others displayed strong platelet inhibition. The present flow cytometry technique appears suitable for identifying patients with abnormal reactions after clopidogrel exposure.

In a study comprising 100 patients referred to a surgical clinic with symptoms suggestive of gastro-oesophageal reflux disease the value of different diagnostic procedures was investigated. Positive acid perfusion and 24-h pH tests were the commonest findings. Forty-nine per cent showed a normal oesophageal mucosa or diffuse oesophagitis at endoscopy. The severity of heartburn and regurgitation did not differ between patients with normal oesophageal mucosa and oesophagitis of various severities. The severity of macroscopic oesophagitis was significantly correlated to the total reflux time, the presence of reflux or a hiatal hernia at radiology, an open cardia or reflux at endoscopy, pressure transmission or reflux and low lower oesophageal sphincter pressure at manometry. Gastric hypersecretion was found in 66% of the patients. Gastric acid secretion was not correlated to the severity of oesophagitis or to the findings at 24-h pH test. In patients with severe oesophagitis the sensitivity for radiologic, manometric, and endoscopic signs of incompetence of the gastro-oesophageal junction was 94%.

All vascular injuries occurring at this hospital department over a 5-year period (1987-91) as a result of cardiac catheterization, coronary angiography, or coronary angioplasty (PTCA) and requiring transfusion, surgical consultation, or repair, are reviewed. Such complications may occur late and, to detect cases not apparent from the protocol accompanying every examination, a questionnaire was sent to all surgical clinics in the region asking for details of vascular surgical intervention after angiography. The present review of 4879 examinations disclosed 18 patients with 19 vascular injuries (0.39%); four of them were detected by the questionnaire. The types of injury were: pseudoaneurysm (12), thrombembolic episode (4), and excessive bleeding (3). Of the patients with a vascular complication 11 (61%) were receiving anticoagulation treatment, compared to 10% in the whole series; two others suffered from a coagulopathic state. Catheterization was difficult or severe atherosclerosis was present in three, inadvertent mobilization occurred in one, and unintentional puncture distal to the common femoral artery occurred in two patients. With the increasing use of invasive diagnostic and interventional procedures in cardiovascular diseases, knowledge of the type and frequency of possible complications is important, especially of those that may occur late. In the present study anticoagulation, coagulation disorders, and cardiac catheterization combined with brachial puncture and angiography all predisposed to a vascular complication.