Cardiovascular and electrocardiographic effects of iopentol in left ventricular angiography. Comparison of the low-osmolar, non-ionic iopentol (Imagopaque 350) and the hyper-osmolar, ionic metrizoate meglumine-Na-Ca (Isopaque Coronar 370) in patients with coronary heart disease.

UNLABELLED: The aim of the study was to evaluate and compare the hemodynamic and electrocardiographic effects following injection of the non-ionic, low-osmolar contrast medium iopentol (Imagopaque 350, Nycomed Imaging AS, Oslo, Norway) and the ionic, hyper-osmolar contrast medium metrizoate meglumine-Na-Ca (Isopaque Coronar 370, Nycomed Imaging AS, Oslo, Norway) when used for left ventricular angiography. The study was performed in a double-blind, randomized manner in 82 patients with severe coronary heart disease. The patients who received iopentol experienced less adverse events and subjective discomfort of lesser intensity than those who received metrizoate (p = 0.0001). Both contrast media induced a biphasic change in left ventricular (LV) systolic pressure, with an initial fall followed by a prolonged rise, but the alterations were statistically significantly more pronounced with metrizoate than with iopentol. The changes in LV end-diastolic pressure (p = 0.023), and LV negative dP/dt (p = 0.002) were significantly more pronounced with metrizoate than with iopentol. Cardiac output and heart rate increased more with metrizoate, while stroke volume was equally increased by both agents. A prolonged increase in the QT-interval, throughout the 10-min observation period, was seen only after injection of metrizoate (p = 0.0006 for comparison between contrast media). CONCLUSION: Iopentol was well tolerated and induced markedly less severe hemodynamic and electrocardiographic alterations than did metrizoate in patients with severe coronary heart disease.

Image quality and safety in pediatric urography using an ionic and a non-ionic iodinated contrast agent.

The safety and diagnostic efficacy of the new non-ionic, monomeric contrast medium iopentol (Imagopaque) were evaluated and compared with those of the ionic medium metrizoate (Isopaque), in urography in children in a randomized, double-blind, parallel study. The trial comprised 59 children aged from 3 months to 8 years; children with predefined risk factors were not included. The difference in attenuation between the renal and perirenal tissue, assessed from film density measurements, was chosen as the main variable. Diagnostic efficacy was also evaluated subjectively from demarcation of the kidney and the pelvic structures. There was no statistically significant difference between the groups in the diagnostic efficacy. Serious adverse events did not occur in either group. Mild to moderate, transient adverse events were significantly less frequent in the iopentol group than in the metrizoate group, but in no case was medical treatment required. There were no changes or trends toward changes of clinical importance in either group, in serum chemistry variables measured in blood samples taken 2 min after injection of contrast medium compared to baseline values.

Inadvertent intrathecal use of ionic contrast media for myelography.

PURPOSE: To describe instances of inadvertent intrathecal injection of ionic contrast media and to consider treatment approaches, and diagnostic and medicolegal issues. METHODS: Ten cases of inadvertent injection, of which nine were reported to the manufacturers/authors and one appeared in the literature, are related with emphasis on similarity of reactions. RESULTS: Six criteria are enumerated and used to coin the term "ascending tonic-clonic seizure syndrome." CONCLUSIONS: Therapeutic possibilities seem limited, but several methods for controlling seizures are suggested. The importance of identifying the contrast material is underscored. Awareness of the grave possibility of administering the wrong contrast material is the first step in avoiding this problem; awareness of the symptoms is the first step toward therapy.

Iopentol in urography. A clinical comparison between iopentol and metrizoate including delayed reactions.

A double-blind comparative study of the nonionic contrast medium iopentol and the ionic contrast medium metrizoate for urography was carried out in 200 adult outpatients. Significantly less discomfort and other side effects were observed following iopentol than following metrizoate. No serious adverse reactions and no clinically significant alterations in heart rate or blood pressure were observed. A questionnaire was used to record delayed symptoms, from 30 min after contrast medium injection and for one week. The response rate was 92% and delayed adverse events were reported by 45%. The incidence of delayed reactions was significantly lower following iopentol than following metrizoate, i.e., delayed arm pain, fatigue, headache, diarrhea, nasal congestion, and rash. Delayed arm pain was probably due to contrast medium induced thrombosis in 1% following iopentol and in 8% following metrizoate. Most other symptoms were probably related to a combination of nocebo effect and coincidentally occurring symptoms. The urograms with both media were of similar high quality. Iopentol was found a suitable contrast medium for urography.

[The evaluation of urinary NAG activity in patients undergoing urography]. / Valutazione dell'attività NAG-urinaria in pazienti sottoposti ad urografia.

A study has been carried out to verify the nephrotoxic effect of hyperosmotic substances used as a contrast medium in radiology employing the enzymuria technique (NAG). The research was carried out in 202 patients, some of whom diabetic, suffering from various pathologies and subjected to perfusion urography by inoculating an iodate contrast medium (isopaque). The result showed that NAG urinary activity grows significant in the 24-36 hours subsequent to X-ray examination in both diabetics and nondiabetics although the increase is greater in the former. After 5-7 days, enzymuria returns to normal in nondiabetic patients but remains high in the diabetic.

The spectrum of isolated ocular reactions following intravascular contrast administration.

Five out of 2930 (0.2%) consecutive patients developed ocular adverse reactions following intravascular administration of sodium-meglumine diatrizoate. The adverse reactions included bilateral blurring of vision (2), unilateral orbital oedema (2) and bilateral intense conjunctival congestion (one patient). The latter two phenomena responded to steroid and antihistaminic agents. Contrast medium-induced ocular anaphylactoid response is rare but clinically significant.

Fulminant pulmonary edema following intravenous administration of radiocontrast media.

A 29-year-old woman who developed fulminant pulmonary edema several minutes after intravenous administration of radiocontrast media (RCM) is reported. The low pulmonary-capillary wedge pressure and the high protein concentration in pulmonary edema fluid indicated a noncardiogenic pulmonary edema related to increased lung vascular permeability. Laboratory studies showed a slight decrease of several complement components (C3, C4 and factor B) and a transient consumption coagulopathy. Potential pathophysiologic mechanisms involved in RCM- induced pulmonary edema are discussed.

Influence of urography on renal function in children. A double blind study with metrizoate and iohexol.

Thirty-two children were given either metrizoate or iohexol for urography in a double blind study. Mild to moderate adverse reactions were observed in all patients receiving metrizoate (15/15) and in 4 receiving iohexol (4/17). Alkaline phosphatase in urine was significantly increased 4 hours after the injection of both media, but had returned to pre-injection levels 16 hours later. The excretion of beta 2-microglobulin and albumin was not altered. In 9 children in the metrizoate group and 11 in the iohexol group the glomerular filtration rate (GFR) was determined before urography by the single injection 99Tcm-DTPA-technique and 3 to 4 hours after urography by measuring the plasma disappearance of the contrast medium with the x-ray fluorescence technique. No reduction of GFR was observed.

Nephrotoxicity of contrast media in patients with diabetes mellitus. A comparative urographic and angiographic study with iohexol and metrizoate.

A double-blind urographic and angiographic study was done with the ionic contrast medium meglumine metrizoate and the non-ionic iohexol in 90 patients with diabetes mellitus. Twenty patients were insulin dependent, and 70 non-insulin dependent diabetics. Diabetic patients with decreased as well as normal renal function prior to the examination sustained a reversible and small increase in the plasma creatinine level postexamination. The small increase caused by meglumine metrizoate was significantly higher than the increase caused by iohexol. There was also a significantly higher increase in plasma creatinine among the patients with diabetic nephropathy compared with those without nephropathy.

Nonionic versus ionic contrast media in intravenous urography: clinical trial in 1,000 consecutive patients.

A double-blind clinical trial was performed in 1,000 consecutive patients to compare the safety and efficacy of intravenously administered nonionic (iohexol) and ionic (metrizoate) urographic contrast media. The patients ranged in age from 10 to 80 years. The incidence of mild to moderate adverse effects was 7.7% with iohexol and 31.2% with metrizoate. No serious reactions were recorded with either of the contrast media. Urography with iohexol was found to give better parenchymal opacification, pelvocalyceal opacification, and overall quality. The sum of examinations with good and excellent overall quality was 97.8% with iohexol and 91.1% with metrizoate. The frequency of poor overall quality urograms was 1.6% with iohexol and 7.5% with metrizoate. The data suggest that iohexol is safer and more frequently produces urograms of better quality.

Complications in cerebral angiography with iohexol (Omnipaque) and meglumine metrizoate (Isopaque cerebral).

The complications of cerebral angiography have been recorded in 1509 examinations with metrizoate (Isopaque Cerebral) and in 1000 examinations with iohexol (Omnipaque). The frequency of complications was 2.0 percent for metrizoate and 1.3 percent for iohexol. Permanent sequelae were seen in 4 patients, 3 in the metrizoate and one in the iohexol group. One of these patients died, probably from thromboembolism. Blood coagulation parameters were studied during the angiography in 22 patients and only minor, probably clinically insignificant changes were found, with no difference between the two contrast media.

Hemodynamic and electrocardiographic consequences of high- and low-osmolality contrast agents for left ventricular angiography.

The cardiovascular effects of two nonionic contrast agents with low osmolality (iohexol and metrizamide) were compared with one standard ionic, high-osmolality contrast agent (metrizoate) used for left ventricular (LV) angiography in patients with coronary heart disease. Metrizoate induced a marked elevation of LV end-diastolic pressure and LV systolic pressure and an increase in cardiac output after a delay of a few minutes. All these changes were significantly less severe with iohexol and metrizamide. Hypotension occurring 30 sec after LV angiography was observed only with use of metrizoate. All agents increased heart rate, but the increase after metrizoate was significantly more pronounced and prolonged. The PQ and QT interval was prolonged only by metrizoate. The subjective symptoms were significantly more marked with metrizoate than with the two other agents. Thus the new nonionic contrast agent iohexol and metrizamide produced markedly less hemodynamic and electrocardiographic disturbance than the ionic agent metrizoate.

Effects of metrizoate and iohexol on the liver at visceral angiography.

Hepatic angiography was performed in a double-blind two-group study in 60 patients using iohexol 350 mg I/ml and metrizoate 350 mg I/ml. A slight increase in serum values of hepatic enzymes was found when metrizoate was used, particularly in patients with impaired liver function. Iohexol gave considerably less pain and sensation of heat than did metrizoate. A non-expected significant increase of creatine kinase was recorded when iohexol was used. The reason for this is not yet known.

Formation of potential antigens from radiographic contrast media.

The use of radiographic contrast media is occasionally accompanied by more or less serious adverse effects, evidently of complex etiology, following intravascular administration. Some of these reactions are suspected of having an allergic basis. The in vitro and in vivo formation of iodinated serum proteins following gamma irradiation in the presence of two commonly used radiographic contrast media is demonstrated. Non-toxic concentrations of ascorbate present during the irradiation is shown to prevent the formation of such iodo-proteins in vitro as well as in vivo. The amounts of potentially antigenic iodoprotein formed during radiographic procedures will certainly be very small, but this quantity may be sufficient to elicit a hypersensitivity reaction in cases when an individual has been previously sensitized to immunologically similar iodo-proteins, a mechanism that could account for certain rare and unpredictable reactions. The radiation induced formation of iodo-proteins may also serve as a model for the formation of iodine containing antigens mediated by a free radical mechanism, i.e. in the metabolism of iodinated compounds like erythrosine, a widely used colouring agent for certain foods.

Abnormal nephrogram pattern as an adverse reaction to contrast material. Case report.

Up to now two abnormal nephrographic patterns have been described as a result of arterial hypotension as an adverse response to urographic contrast material. We would like to describe a third pattern.

Selective injection of iopentol, iohexol and metrizoate into the left coronary artery of the dog. Induction of ventricular fibrillation and decrease of aortic pressure.

In twenty beagle dogs selective injections were made into the left coronary artery with iopentol, iohexol and metrizoate in doses of 4 ml, 8 ml and 16 ml. Thirty-six iopentol injections, 35 iohexol injections and 37 metrizoate injections were made. Frequencies of ventricular fibrillation were significantly lower (p less than 0.05) after iopentol (0%) and iohexol (3%) than after metrizoate (22%). Iopentol and iohexol also produced significantly less decrease in aortic blood pressure than metrizoate at the different doses.

Herniography: comparison of morbidity and image quality after use of high and low osmolality contrast media.

The morbidity and image quality after administration of three different contrast media were compared in 229 patients referred for herniography. Sixty patients received metrizoate 150 mg I/ml, 92 received metrizoate 200 mg I/ml, and 77 patients, ioxaglate 200 mg I/ml. Patient discomfort was single-blindedly assessed based on an arbitrary verbal rating scale. The number of patients with pain increased with the osmolality of the contrast media. Metrizoate 200 induced pain in 57% of the patients, metrizoate caused pain in 39%, and ioxaglate 200 in 18%. Hernia patients who received metrizoate 200 had pain significantly more often (72%) than patients without hernia (45%). Seven patients, predominantly young men, had a vasovagal reaction associated with the administration of contrast media. The image quality was sufficient after all injections of 200 mg I/ml. The results indicate that low osmolality contrast media with an iodine concentration of about 200 mg I/ml are well suited for herniography.