Early and late reactions after the use of iopamidol 340, ioxaglate 320, and iodixanol 320 in cardiac catheterization

Adverse Reactions of Low Osmolar Non-Ionic and Ionic Contrast Media When Used Together or Separately During Percutaneous Coronary Intervention

BACKGROUND

Due to perceived advantages in the use of non-ionic contrast agents for diagnostic angiography and ionic agents for percutaneous coronary intervention (PCI), patients often receive various combinations of both types of agents.

AIM

To assess potential adverse effects of non-ionic and ionic contrast media when used together or separately during percutaneous coronary intervention.

METHODS

We retrospectively evaluated the outcomes of 532 patients undergoing percutaneous coronary intervention in our institution. Patients were divided into two groups: those that underwent diagnostic angiography and "follow on" PCI; and those that underwent "planned" PCI. The groups were subdivided on the basis of the use of the ionic agent ioxaglate or the non-ionic agent iopromide during PCI. The frequency of allergic reactions and major adverse cardiac events (MACE) were noted.

RESULTS

With respect to the "follow on" group, allergic reactions occurred in 9 of 150 patients (6.0%) who received the combination of ioxaglate and iopromide versus 1 of 93 (1.1%) who only received iopromide (p=0.094). There was no difference with respect to MACE [6 (4.0%) ioxaglate and iopromide versus 4 (4.3%) iopromide alone, p=1.00]. In the "planned" group, 7 of 165 patients (4.2%) receiving ioxaglate had an allergic reaction as opposed 0.0% (0 of 124 patients) in the iopromide group (p=0.021). All contrast reactions were mild. The incidence of a MACE was similar in both groups [1 (0.6%) ioxaglate versus 2 (1.6%) iopromide, p=0.579]. The incidence of allergic reactions was similar if ioxaglate was used alone or in combination with iopromide (p=0.478).

CONCLUSIONS

Whilst combining ionic and non-ionic contrast agents in the same procedure was not associated with any more adverse reactions than using an ionic contrast agent alone, the ionic contrast agent ioxaglate was associated with the majority of allergic reactions. With respect to choice of contrast agent, using the non-ionic agent iopromide alone for coronary intervention is associated with the lowest risk of an adverse event.

The no-flow phenomenon during diagnostic coronary angiography

OBJECTIVES

Slow flow of dye in epicardial coronary arteries is not an infrequent finding in patients during routine coronary angiography. The extreme form of this phenomenon, namely, no flow or Thrombolysis in Myocardial Infarction (TIMI) 0-1, is very uncommon with life-threatening consequences. We consider the present report as the first one, to our knowledge, that describes this angiographic entity and how prompt recognition and adequate management prevent certain death in this population.

DESIGN, SETTING, AND PATIENTS

Retrospective review of the cardiac catheterization laboratory database at our medical center. Out of 5700 cardiac catheterizations performed by the authors during the past 5 years, 10 cases (0.17%) were identified as having no flow or very slow flow during their routine diagnostic coronary angiogram.

CASE ANALYSIS

The no-flow phenomenon occurred during the first coronary injection in the left coronary system. We specifically emphasize that none of these cases was a consequence of inadvertent air injection, vasospasm, or coronary dissection. In 80% of our cases, flow was completely absent (TIMI 0), and in two cases (20%) it was very slow and never filling the distal vessel (TIMI 1). Despite immediate recognition and prompt maneuvers and treatment with intracoronary vasodilator administration, 60% of these patients progressed to full cardiopulmonary arrest with all of them having extended cardiopulmonary resuscitation (CPR) and pharmacological treatment. Only one patient required intra-aortic balloon pump (IABP) support and temporary pacemaker. All patients recovered completely with no clinical consequences. Characteristics of patients with this complication are described, and several possible etiologies are analyzed.

CONCLUSIONS

Definite conclusions for the reason of the no-flow phenomenon are not possible at present, despite multiple different theories that could explain it. What is important from the clinical standpoint is that, although rare, it is a potentially life-threatening condition during diagnostic coronary angiography that should be recognized and aggressively treated. We consider the present report as the first one, to our knowledge, that describes this angiographic entity, and how prompt recognition and adequate management prevents certain death in this population.

Allergy-like reactions to iodinated contrast agents. A critical analysis

Allergy-like reactions may occur following administration of iodinated contrast media (CM), mostly in at-risk patients (patients with history of previous reaction, history of allergy, co-treated with interleukin-2 or beta-blockers, etc.) but remain generally unpredictable. Severe and fatal reactions are very rare events. All categories of CM may induce such reactions, although first generation (high osmolar CM) have been found to induce a higher rate of adverse events than low osmolar CM. However, no differences were found between the two categories of CM with respect to mortality. Delayed reactions can also occur. There are no differences between the various categories of CM except for non-ionic dimers, which are more likely to induce such effect. Numerous clinical studies have evaluated the prophylactic value of drugs (mostly antihistamines and corticosteroids). Results are unclear and highly variable. Any prevention depends upon the mechanism involved. However, the mechanism of CM-induced allergy-like reaction remains disputed. Relatively recent data revived the hypothesis of a type-I hypersensitivity mechanism. Positive skin tests to CM have been reported. However, the affinity of IgE towards CM has been found to be very low in the only study which actually evaluated it. Other pathophysiological mechanisms (involving direct secretory effects on mast cells or basophils, or activation of the complement system associated or not with the plasma contact system) are also much debated. Anaphylaxis and anaphylactoid reactions are, in the end, clinically undistinguishable.

Pain in femoral arteriography. A double-blind, randomized, clinical study comparing safety and efficacy of the iso-osmolar iodixanol 270 mgI/ml and the low-osmolar iomeprol 300 mgI/ml in 9 European centers

PURPOSE

To compare the injection-associated pain and heat sensation after administration of the iso-osmolar contrast medium (IOCM) iodixanol (Visipaque trade mark 270 mg I/ml) and the low osmolar contrast medium (LOCM) iomeprol (Iomeron trade mark 300 mg I/ml) in femoral arteriography.

MATERIAL AND METHODS

352 patients received iodixanol or iomeprol in a prospective, double-blind, randomized, parallel-group clinical trial. The first injection during femoral arteriography (DSA with automated stepping) was standardized. Injection-associated pain and heat sensation, efficacy and safety up to 72 h were evaluated.

RESULTS

The iodixanol group reported significant less injection-associated pain than the iomeprol group after the first injection (7.4% vs. 17.6%; p = 0.007), and after all injections (11% vs. 19.4%; p = 0.045). Iodixanol caused less heat sensation after the first injection (p = 0.007) and after all injections (p = 0.029). Heat sensations in the iodixanol group were less intense after all injections (p < 0.0001). No difference was found between the groups regarding the frequency of patients having adverse reactions (5.1% vs. 4%).

CONCLUSION

The IOCM iodixanol caused significantly less frequent injection-associated pain and heat sensation than the LOCM iomeprol during femoral arteriography.

Effects of hyperosmolar ionic and low osmolar non-ionic contrast media on coagulation times and some blood parameters in dogs: an in vivo study

The purpose of this study is to evaluate the effects of hyperosmolar ionic contrast media (CM) (diatrizoate) and low osmolar non-ionic CM (iohexol and ioxilan) on coagulation time and some blood parameters in dogs in vivo. The animals were divided into three groups in equal numbers. The dogs in groups I, II and III received diatrizoate, iohexol and ioxilan at the dose of 700 mgI/kg intravenously (IV) as a bolus, respectively. Administration of contrast media and blood samples were collected from vena cephalica antebrachii prior to CM administration and thereafter at 3, 15, 30, 60, 90 and 180 min and 24 h to measure the coagulation factors [activated partial thromboplastin time (APTT), prothorombin time (PT), fibrinogen and fibrinogen degradation products] and some other blood parameters [red blood cells, platelet, white blood cells, haematocrit (Ht) and haemoglobin (Hb)]. While a statistically significant decrease was observed on APTT at 15 min in group III, no significant differences were found in groups I and II. All the groups had insignificant alterations for PT, fibrinogen and fibrinogen degradation product, following CM administration. Significant decreases were observed for platelet at 3 min in all groups. This decrease was also significant at 15- and 30- min intervals in group I. There were significant decreases for erythrocytes, Ht and Hb measurements within 30 min, and no significant alterations were observed for leucocytes within 60 min in all groups compared with baseline values. No differences were observed with regard to coagulation times and some blood parameters as far as long-lasting and major effects of each CM are concerned.

Comparative tolerability of contrast media used for coronary interventions

Radiographic contrast media (CM) are necessary to provide x-ray absorption of the bloodstream; all other observed effects need to be regarded as adverse. Four types of CM are currently used in diagnostic and interventional cardiology: ionic high-osmolar CM (HOCM), either ionic or non-ionic low-osmolar CM (LOCM), and non-ionic iso-osmolar CM (IOCM). Focusing on the potential cardiovascular effects caused by the CM, there is a clear difference between HOCM and the LOCM or IOCM. HOCM have a poorer profile due to a higher incidence of hypotension and electrophysiological effects. To prevent contrast-induced nephropathy, HOCM should be avoided and patients should receive the minimal dose of LOCM or IOCM with intravenous hydration before and after the procedure. Clinical hyperthyroidism has been detected after CM use, but the condition appears, ultimately, to be self-limited and to occur mainly in elderly patients. When assessing the need for a CM in terms of improved patient safety, preventing serious complications should be the major factor determining the choice. CM should not be selected on the basis of minor adverse effects since these are, ultimately, of low clinical relevance. Thrombotic events, in contrast, carry a high clinical relevance and we consider that these should be the main issue governing current choice. Ionic LOCM appear to have better profile than other CM with respect to interaction with platelet function and coagulation. In relation to thrombotic events in randomised clinical studies, ionic CM have been associated, mainly, with favourable and some neutral results compared with non-ionic agents. Only one trial indicated a more pronounced antithrombotic effect of the non-ionic IOCM relative to the ionic LOCM. The antithrombotic advantages of ionic over non-ionic LOCM are, in part, balanced by a greater frequency of minor adverse effects such as nausea, vomiting or cutaneous rashes. A matter of concern is the delayed adverse effects observed with non-ionic IOCM. However, severe and life-threatening reactions are exceptional and there are probably no significant differences between IOCM and LOCM whether ionic or non-ionic. However, in patients with known allergies, non-ionic CM are to be recommended. On the basis of the available pre-clinical and clinical data, the ionic LOCM or the non-ionic IOCM are the agents to be recommended in percutaneous coronary interventions because of their antithrombotic advantages over non-ionic LOCM.

A randomized prospective trial of ioxaglate 320 (Hexabrix) vs. iodixanol 320 (Visipaque) in patients undergoing percutaneous coronary intervention

We performed a randomized, prospective, double blind trial comparing the use of the ionic dimer contrast agent ioxaglate 320 (Hexabrix) with the nonionic dimer contrast agent iodixanol 320 (Visipaque) in 618 patients undergoing percutaneous coronary intervention (PCI) for stable or unstable coronary artery syndromes. The aim was to determine whether the different anticoagulant and antiplatelet properties of these two contrast agents resulted in a significant difference in the incidence of a combined endpoint comprising the major complications of PCI. Procedural success rates were marginally higher in the Visipaque group compared to the Hexabrix group, although this did not reach statistical significance (96.7% vs. 93.9%; P = 0.09). There was a borderline statistically significant higher requirement for bailout stenting in the Visipaque group compared to the Hexabrix group (6.8% vs. 3.2%; P = 0.05), although this was not a predefined endpoint. The incidence of the combined primary endpoint of failed catheter laboratory outcome/requirement for bailout stenting/requirement for abciximab/myocardial infarction/death before hospital discharge was higher in the Visipaque group compared to the Hexabrix group (17.9% vs. 14.8%), although this did not reach statistical significance (P = 0.29). When subgroup analysis was performed, the incidence of the combined endpoint in patients with stable coronary artery disease randomized to receive either Visipaque or Hexabrix was identical (13.7%). In patients with an acute coronary syndrome, there was a trend toward a reduced incidence of the combined endpoint in the Hexabrix compared to the Visipaque group, although this did not reach statistical significance (17.2% vs. 24.8%; P = 0.17). More adverse reactions occurred in the Hexabrix group compared to the Visipaque group (8.7% vs. 4.9%; P = 0.06). We conclude that there is no clear advantage with the use of an ionic contrast agent in a large population of patients undergoing PCI for both stable and unstable coronary artery disease. Although the study was underpowered to detect significant differences with the use of either agent when patients with either stable or unstable coronary disease were studied, it is highly unlikely that the ionicity of the contrast agent confers any advantage for patients with stable coronary disease. There remains a possibility that ionic agents do have advantages for patients with unstable coronary artery disease undergoing PCI, although a larger study than ours would be required to confirm or refute this.

Late-onset allergy-like reactions to X-ray contrast media

PURPOSE OF REVIEW

The purpose of the present review is to describe recent insight into the pathomechanism of the late-onset allergy-like reactions which affect 2-3% of contrast medium-exposed patients, and to give advice regarding prophylactic measures to avoid recurrence of such reactions.

RECENT FINDINGS

It is well recognized that the majority of contrast media-induced late-onset reactions are cutaneous reactions of the maculopapular, urticarial and angioedema types, with occasional occurrence of more serious, bullous eruptions. Recent findings strongly indicate that these reactions are T cell-mediated. The current evidences for this concept are the described clinical symptoms; the high incidence of reactions in interleukin-2-treated patients; the positive results from skin, provocation and lymphocyte transformation testing of affected patients; and the histopathology of skin eruptions and positive skin test sites.

SUMMARY

On the basis of this new knowledge, several prophylactic measures are proposed to avoid repeat reactions in patients with previous late-onset contrast medium reactions. All persons receiving contrast media should be informed that transient skin reactions may develop up to 7 days after contrast medium exposure. Those who experience such reactions should be advised to see an allergist for diagnosis of the reaction. Skin testing with a panel of different contrast media appears to be useful for confirming the presence of an allergic reaction and for identifying alternative contrast media that can be safely used. For undiagnosed persons, a contrast medium that is structurally different from the product that precipitated the reaction should be chosen if re-exposure to contrast media is required. Pretreatment with corticosteroids may also be tried, although its protective effect has not been systematically studied.

Acute cardiac tolerance of current contrast media and the new taxane protaxel using iopromide as carrier during porcine coronary angiography and stenting

RATIONALE AND OBJECTIVES

The systemic tolerance thresholds of modern low-osmolar x-ray contrast media (CM) are similarly high, but their effects on the cardiovascular system and on the coagulation differ. The aim of this study was to comparatively evaluate the cardiovascular tolerability of iopromide, ioxaglate, and iosmin, and of a novel taxane protaxel, dissolved in iopromide, as a carrier, by coronary angiography and stenting.

METHODS

Sixteen pigs were randomized into four groups: iosmin (350 mg iodine/mL, n = 4, nonionic dimer), iopromide (370 mg iodine/mL, n = 4, nonionic monomer), ioxaglate (320 mg iodine/mL, n = 4, ionic dimer), and 70-micromol protaxel dissolved in iopromide 370 mg iodine/mL, intended to prevent restenosis. Coronary angiography was performed via the left carotid artery followed by implantation of stents into the left anterior descending and the circumflex arteries. About 80 mL per animal was used in each group.

RESULTS

There were no thrombotic complications and no significant adverse events of electrocardiography, blood pressure, or contractility during or after CM injections. There were no differences among the CM tested except that ioxaglate was the only agent showing a significant reduction in dp/dt after 50 seconds compared to iosmin. The values of preinjection parameters were most rapidly regained after iosmin, compared with other CM tested.

CONCLUSIONS

The novel iso-osmolar nonionic CM iosmin is well tolerated in porcine coronary angiography and subsequent stenting. The cardiac tolerance of iopromide has not been adversely affected by addition of the cytostatic protaxel.