Effect of calcium-binding additives on ventricular fibrillation and repolarization changes during coronary angiography

Nonrenal Complications of Contrast Media

Injection of contrast media is the foundation of invasive and interventional cardiovascular practice. Iodine-based contrast was first used in the 1920s for urologic procedures and examinations. The initially used agents had high ionic and osmolar concentrations, which led to significant side effects, namely nausea, vomiting, and hypotension. Newer contrast agents had lower ionic concentrations and lower osmolarity. Modifications to the ionic structure and iodine content led to the development of ionic low-osmolar, nonionic low-osmolar, and nonionic iso-osmolar contrast media. Contemporary contrast agents are better tolerated and produce fewer major side effects.

Nonrenal Complications of Contrast Media

Nonrenal complications of contrast media are caused by chemotoxic or anaphylactoid reactions related to the contrast agent used. Chemotoxicity is mainly attributed to ionic concentration and osmolality. Anaphylactoid reactions are typically caused by direct activation of basophils, mast cells, and complement rather than an observable antigen-antibody interaction, and may be acute or delayed. History of an adverse reaction following prior exposure is the strongest predictor of a subsequent adverse reaction to contrast. Premedication regimens of corticosteroids or antihistamines can lower the risk of repeat adverse reactions. Treatment of anaphylactoid reactions depends on the severity of symptoms.

Risks and complications of coronary angiography: a comprehensive review

Coronary angiography and heart catheterization are invaluable tests for the detection and quantification of coronary artery disease, identification of valvular and other structural abnormalities, and measurement of hemodynamic parameters. The risks and complications associated with these procedures relate to the patient’s concomitant conditions and to the skill and judgment of the operator. In this review, we examine in detail the major complications associated with invasive cardiac procedures and provide the reader with a comprehensive bibliography for advanced reading.

The Clinical Value of the ECG in Noncardiac Conditions

The ECG is an indispensable tool in the ICU for the detection and diagnosis of heart disease. ECG abnormalities however can be present in a wide variety of noncardiac conditions, complicating the differential diagnosis with primary cardiac pathology. This overview discusses the ECG abnormalities and their pathophysiologic basis in the most frequently encountered noncardiac conditions, such as electrolyte abnormalities, pulmonary embolism, CNS diseases, esophageal disorders, hypothermia, and drug-related and other conditions. Knowledge of the characteristic ECG changes may provide early clues to the presence of these disorders, the prompt recognition of which can be life saving.

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.

Mechanisms of ventricular fibrillation during coronary angioplasty: increased incidence for the small orifice caliber of the right coronary artery

BACKGROUND

Ventricular fibrillation (VF) is not an infrequent complication of percutaneous transluminal coronary angioplasty (PTCA). However, it is not clear why there is a marked discrepancy in the higher incidence of VF during right coronary artery (RCA) approach.

METHODS AND RESULTS

We analyzed in detail every case of VF occurring in 905 consecutive PTCA procedures to investigate possible mechanisms. Sixteen patients (M/F=15/1, mean age: 71 +/- 8 years) with VF during PTCA for the RCA as Group I. Those 51 patients (M/F=48/3, mean age: 70 +/- 9 years) without VF during PTCA for the RCA engagement were designated as Group II. Patients were equipped with cardiac event recorder (CardioCall, Reynolds Medical, UK) before the PTCA, and we set the time period 1 min before and after the event. The lead II was selected to check the QRS width, QTc interval, ST segment change and RR interval before and after event. A total of 905 PTCA procedures were included. There were 561 procedures for the left coronary artery and three events (0.5%) with spontaneous VF. However, there were 16 events (4.6%) of VF during 344 PTCA procedures for the right coronary artery. The incidence of VF for the right side PTCA was significantly higher than for the left side. The orifice of RCA in Group I was smaller than Group II (orifice of RCA in Group I vs. Group II - 2.7+/-0.8 vs. 4.1+/-1.2 mm, P<0.001). Most cases (68.7%) presented with ST segment depression before the onset of VF.

CONCLUSION

A small caliber of RCA and associated ST segment changes played important roles in the patients with VF during the PTCA.

Iomeprol and iopamidol in cardiac angiography: a randomised, double-blind, parallel-group comparison

During cardiac angiography, hemodynamic alterations and surface electrocardiographic changes are common, predictable and dose-related adverse reactions to radiocontrast media. High osmolality, inadequate sodium content and local transient hypocalcemia are thought to be the main mechanisms responsible for these untoward cardiovascular effects. The purpose of this double-blind, parallel-group trial was to compare the hemodynamic and electrocardiographic responses to cardiac and selective coronary artery injection of iomeprol 400 (400 mgI/ml) and iopamidol 370 (370 mgI/ml). One-hundred consenting adult inpatients were randomised to receive iomeprol 400 (41 males, nine females; mean age, 56.6 years) or iopamidol 370 (46 males, four females; mean age, 57.6 years). Both agents produced minor and transient hemodynamic and electrophysiological effects. Following left ventriculography, iopamidol 370 produced a significantly greater increase in LVEDP than iomeprol 400 (mean increases after first and second left ventriculogram: 2.5 and 4.6 mmHg with iomeprol 400, 3.3 and 9.9 mmHg with iopamidol 370, P = 0.027). The QT-interval was more affected by iopamidol 370 than by iomeprol 400. However, post-contrast prolongation of the QT-interval was not significant with either agent, nor were there any significant T-wave, ST-segment or RR-interval changes associated with the injection of the test compounds. No serious adverse events occurred throughout the study. Mild pain was complained by only one patient, while most patients reported mild to moderate sensation of heat. Image quality of the vast majority of the procedures was rated as good or excellent in both patient groups.(ABSTRACT TRUNCATED AT 250 WORDS)

A comparison of low- with high-osmolality contrast agents in cardiac angiography. Identification of criteria for selective use

BACKGROUND

Controversy exists as to whether low-osmolality radiographic contrast agents, which have less detrimental pharmacological effects but are considerably more expensive than high-osmolality agents, should be used universally or only for selected high-risk patients.

METHODS AND RESULTS

A randomized, double-blind study was used to compare the frequency and severity of adverse events in 2245 consecutive patients undergoing diagnostic cardiac angiography. Two thousand one hundred sixty-six patients were successfully randomized to either iohexol, a low-osmolality contrast agent, or diatrizoate (as Hypaque 76), a high-osmolality agent. The end point event included clinically important adverse events (which jeopardized the patient or required aggressive treatment), contrast agent-related procedure abbreviations, and conversion to open-label contrast agent. Clinically important end point events were associated with increased age, New York Heart Association functional class, left ventricular end-diastolic pressure, arteriovenous oxygen difference, severity of coronary artery disease, and history of a previous reaction to contrast agent. End point events were less frequent in patients receiving iohexol (2.6% versus 4.6%; adjusted odds ratio, 1.59; 95% confidence interval, 0.97-2.60; P = .07). The difference in event frequency between iohexol and diatrizoate was confined to the highest-risk quartile of the patient population. An algorithm was developed to classify patients as being at high or low risk for an event based on patient age, New York Heart Association class, history of a prior contrast reaction, and left ventricular end-diastolic pressure. Application of this algorithm for selective use of low-osmolality agents only for high-risk patients to a theoretical population of 1000 patients reduced contrast agent costs 66% without increasing the frequency of contrast agent-related adverse events.

CONCLUSIONS

The advantages of low-osmolality contrast agents are clinically important in patients with severe heart disease but are not in less ill patients. Universal use of low-osmolality agents for cardiac angiography in an unselected population is not necessary. Appropriately guided selective use of low-osmolality contrast agents is feasible and has the potential to reduce cost substantially without compromising safety or effectiveness.

Evidence for a reexcitability gap in man after treatment with type I antiarrhythmic drugs

The intention of this study was to determine whether type IA antiarrhythmic drugs cause a disparity between refractoriness and repolarization, and if so, its magnitude. We simultaneously measured monophasic action potential duration (MAPD) and effective refractory period (ERP) at a right ventricular site in 11 patients without overt right ventricular disease. The pacing protocol, which included sinus rhythm and a 600 and 400 msec cycle length of ventricular drive, was performed at baseline and after the intravenous administration of 15 mg/kg of procainamide in nine patients, and of 10 mg/kg of quinidine in two patients. Despite trivial changes in sinus rates, drug therapy caused a 10% to 17% increase in MAPD and ERP that shortened with decreasing drive cycle lengths. At baseline there was a small gap (10 to 13 msec) between MAPD and ERP in sinus rhythm and with a 600 or 400 msec drive. However, the type IA drug caused a significant widening of this gap that was most profound in sinus rhythm (45 msec) and that shortened but was not abolished with a 600 and 400 msec drive (28 and 29 msec, respectively). The disparity was caused in one third of cases by postrepolarization refractoriness. Type I drugs increase the difference between repolarization and refractoriness, and this effect is partially reversed with increases in heart rate. The clinical implications of these findings are discussed.

Use of nonionic or low osmolar contrast agents in cardiovascular procedures. American College of Cardiology Cardiovascular Imaging Committee

Low osmolar contrast agents produce less adverse electrophysiologic and hemodynamic alterations during cardiac catheterization. The nonionic agents probably reduce the risk of provoking myocardial ischemia during coronary arteriography or ventriculography. Patients also report less subjective sensation of discomfort during administration of low osmolar agents for cardiovascular procedures. However, nonionic agents have not been proved to reduce the incidence of several serious complications of cardiac catheterization, including acute renal failure and anaphylactoid reaction. Although evidence is inconclusive, there may be an increased risk of thromboembolic complications during cardiac catheterization when certain low osmolar nonionic agents are administered. Nonionic contrast agents have not been definitely proved to reduce the risk of death after cardiac catheterization.

Adverse reactions of low osmolality contrast media during cardiac angiography: a prospective randomized multicenter study

A multicenter study was performed to determine the incidence of adverse reactions to two contrast media with similar low osmolality during cardiac angiography. The study was of a randomized double-blind design comparing ioxaglate (an ionic dimer) and iopamidol (a nonionic compound) and included 500 patients; 250 patients received ioxaglate and 250 iopamidol. There were 58 adverse reactions attributed to the contrast media in the ioxaglate group and 29 in the iopamidol group (p less than 0.001). Chest pain occurred in 11 patients in the ioxaglate group compared with 5 in the iopamidol group (p = 0.123). Nausea or vomiting was present in 20 and 2 patients, respectively (p less than 0.0003). Allergic adverse reactions, such as bronchospasm, urticaria and itching, occurred in 15 of the ioxaglate group and only 1 of the patients receiving iopamidol (p less than 0.0007). Fifty-two patients in the ioxaglate group had a known allergic history (not to contrast medium) or asthma, whereas 77 receiving iopamidol had a similar history. Seven of the 52 ioxaglate-treated patients developed an allergic adverse reaction compared with none of the 77 in the iopamidol group (p = 0.001). Of 41 patients receiving ioxaglate who were premedicated with diphenhydramine, 4 had an allergic adverse event. In the iopamidol group 45 patients received similar premedication and none had an allergic adverse reaction (p less than 0.03). Thus, this multicenter study shows that adverse reactions occur more often with ioxaglate than with iopamidol and that patients with an allergic history have a greater risk with ioxaglate therapy compared with iopamidol.

A comparison of nonionic, low-osmolality radiocontrast agents with ionic, high-osmolality agents during cardiac catheterization

BACKGROUND

Nonionic, low-osmolality radiocontrast agents are used frequently because they are believed to be safer than ionic, high-osmolality agents, but they are also more expensive. We conducted a randomized trial to compare the incidence of adverse events after the administration of ionic, high-osmolality and of non-ionic, low-osmolality radiocontrast agents during cardiac angiography.

METHODS

We compared the need to treat patients for adverse reactions and the frequency and severity of specific hemodynamic, systemic, and symptomatic side effects in two groups of patients randomly assigned to receive either ionic, high-osmolality or nonionic, low-osmolality radiocontrast material, and also in 366 patients who could not be randomized.

RESULTS

Treatment for adverse events was required in 213 of 737 patients who received high-osmolality contrast agents (29 percent) but in only 69 of 753 patients who received nonionic agents (9 percent) (95 percent confidence interval for the percent difference, 15.9 to 23.6 percent). Hemodynamic deterioration and symptoms also occurred more often in the high-osmolality group, as did severe or prolonged reactions (2.9 percent, as compared with 0.8 percent in the nonionic group; P = 0.035). The severe reactions were largely confined to patients with severe cardiac disease. Multivariate analysis showed that the presence of severe coronary disease and unstable angina were predictors of clinically important adverse reactions. If all the patients in our randomized trial had been given nonionic contrast material, the incremental cost per procedure would have been $89.

CONCLUSIONS

Nonionic, low-osmolality contrast material is better tolerated during cardiac angiography than ionic, high-osmolality contrast material. Since cost constraints may prevent the universal use of nonionic contrast material, its selective use in patients with severe cardiac disease could be considered.

Safety and cost effectiveness of high-osmolality as compared with low-osmolality contrast material in patients undergoing cardiac angiography

BACKGROUND AND METHODS

Low-osmolality contrast agents produce fewer hemodynamic and electrophysiologic alterations during cardiac angiography, but they are 20 times more expensive than high-osmolality contrast agents. In a randomized, double-blind trial comparing a nonionic low-osmolality contrast agent (Omnipaque 350) with a high-osmolality agent that does not avidly bind calcium (Hypaque 76) in 505 patients undergoing cardiac angiography, we determined the incidence of minor, mild, moderate, and severe adverse reactions, identified risk factors for such reactions, and evaluated the cost effectiveness of various strategies for the use of contrast material.

RESULTS

The 253 patients who received a high-osmolality contrast agent were three times more likely to have a moderate adverse reaction (95 percent confidence interval for the relative risk, 1.6 to 5.5) but no more likely to have a severe reaction (95 percent confidence interval, 0.2 to 2.3) than the 252 patients who received a low-osmolality agent. All 10 severe reactions occurred in patients who were older than 60 years or had unstable angina. Patients with these characteristics were also 3.5 times more likely (95 percent confidence interval, 1.8 to 6.8) to have a moderate reaction (44 of 310 patients, or 14 percent) than those without either characteristic (8 of 195 patients, or 4 percent). We estimated that the incremental cost of each moderate reaction avoided would be $1,698 with a strategy that involved giving a low-osmolality contrast agent only to patients who were over 60 years of age or had unstable angina, instead of giving a high-osmolality agent to all patients. The incremental cost per moderate reaction avoided by giving a low-osmolality contrast agent to all patients rather than only to those over 60 or with unstable angina would be $5,842.

CONCLUSIONS

The use of contrast agents with low rather than high osmolality during cardiac angiography reduces the risk of moderate, but not of severe, adverse reactions to the agent used. A strategy of reserving low-osmolality contrast agents for use in patients at high risk for adverse reactions would be more cost effective than one requiring their use in all patients.

Contrast agents for cardiac catheterization: conceptions and misconceptions

Ionic and nonionic contrast materials are similarly efficacious in providing excellent images with minimal risk to the patient. In comparison with ionic media, the nonionic agents produce minor alterations in intracardiac and peripheral pressures as well as in electrocardiographic intervals and morphology. In addition, nonionic media are less often associated with undesirable symptoms, such as flushing and vomiting. At the same time, ionic and nonionic media are accompanied by a similar incidence of nephrotoxicity, serious arrhythmias, and death. Finally, nonionic contrast material is substantially more expensive than ionic media. In light of this marked difference in cost, one could argue that nonionic media should be reserved for "high-risk" patients, that is, those with a history of a serious adverse reaction to ionic contrast media and those in whom contrast-induced hypotension would be particularly deleterious.

Effects of nonionic versus ionic contrast media on complications of percutaneous transluminal coronary angioplasty

To evaluate the effect of contrast agents on percutaneous transluminal coronary angioplasty (PTCA) complications, 913 patients undergoing 1,058 separate PTCA procedures were prospectively randomized to receive either nonionic iopamidol (Isovue-370) [n = 507 PTCA procedures] or ionic contrast media, meglumine sodium diatrizoate (Renografin-76) [n = 551 PTCA procedures]. Angioplasty operators, technicians, nurses and patients were blinded to the agent used. All patients were pretreated with 0.6 mg of atropine sulfate intravenously before any contrast injections. Hypotension (mean arterial pressure less than 65 mm Hg associated with contrast injections) occurred during 8.5% of PTCA procedures in which the patients were receiving iopamidol and during 9.5% of the procedures in which the patients were given diatrizoate (difference not significant). Bradycardia (heart rate of less than 40 beats/min associated with contrast injections) developed during 5.7% of procedures when patients were given iopamidol and during 5.1% of procedures when patients were given diatrizoate (difference not significant). The need for additional atropine or temporary pacing during the procedure was similar for patients given iopamidol and diatrizoate. The overall incidence of ventricular tachycardia or fibrillation, or both, during the procedure occurred less frequently when iopamidol was used compared with diatrizoate (1 vs 2.5%, p = 0.045). These serious ventricular arrhythmias were attributable to contrast injections in 0.6% of the PTCA procedures when iopamidol was given and in 2.0% of the cases in which diatrizoate was the contrast agent (p = 0.09). Only 1 patient had an allergic reaction to the contrast agent, and this was in a patient who received iopamidol.(ABSTRACT TRUNCATED AT 250 WORDS)

Significance of ventricular tachyarrhythmias complicating cardiac catheterization: a CASS Registry Study

Ventricular tachycardia and ventricular fibrillation are recognized complications of cardiac catheterization. Despite numerous reports documenting the frequency of these occurrences, their significance has not been systematically examined. Accordingly, the outcome of 108 patients who experienced either ventricular tachycardia or ventricular fibrillation during coronary angiography between 1975 and 1979 in the Coronary Artery Surgery Study (CASS) Registry were examined. There were 20,142 patients analyzed. Patients with ventricular tachyarrhythmias had more objective evidence of left ventricular impairment, clinical heart failure, and ventricular arrhythmia recorded as a clinical symptom. The overall 5-year survival rates were 83% and 88% for patients with and without ventricular tachyarrhythmias, respectively (p = 0.07). When ventricular function, age, gender, angina, and previous myocardial infarction were added in a stepwise Cox survival analysis, the presence of arrhythmias was not significant (p = 0.66). At 5 years, 80% of the medically treated patients and 82% of the surgically treated patients remained alive (p = 0.95). The only statistically significant differences in the patients with ventricular arrhythmias who were treated medically or surgically were age (medically treated patients 52 +/- 10 years, surgical patients 57 +/- 9 years, p = 0.01) and number of diseased vessels (p less than 0.001). In a stepwise Cox survival analysis, functional impairment secondary to congestive heart failure was the only significant covariate to affect survival in the medical and surgical groups (p = 0.0001). Surgical therapy itself was not significant (p = 1.00). The incidence of sudden death during 5 years for patients with and without ventricular tachyarrhythmias during catheterization was 5% and 4%, respectively (p = 0.28).(ABSTRACT TRUNCATED AT 250 WORDS)

Polymorphous ventricular tachycardia: a side effect of intracoronary papaverine

Polymorphous ventricular tachycardia occurred in 1.3% of patients (5 of 391) who received intracoronary papaverine over a 47 month period. The arrhythmia lasted less than 1 min in all five patients, converting spontaneously in four and requiring electrical cardioversion in one. Ventricular tachycardia occurred in 4.4% of women (4 of 90) and 0.3% of men (1 of 301) (p less than 0.0025). Only one of the patients with ventricular tachycardia had coronary artery disease. To determine whether other clinical or procedural factors predispose patients to this side effect of papaverine, these 5 patients were compared with 25 control patients who were matched for gender and extent of coronary artery disease. The following variables were analyzed: age, baseline serum potassium and calcium levels, left ventricular ejection fraction, baseline heart rate, mean arterial pressure, corrected QT interval, the change in corrected QT interval produced by papaverine and the maximal dose of the drug per kilogram of body weight. Of these variables, only baseline heart rate differed significantly in the two groups of patients. Thus, polymorphous ventricular tachycardia is an infrequent, but important, side effect of papaverine that is usually self-limited. Women with a relatively slow heart rate appear to be predisposed to this side effect.

Reduction of ventricular arrhythmias by atropine during coronary arteriography

Sustained ventricular arrhythmia is a well-recognized complication of cardiac catheterization, often occurring after selective coronary artery injection of contrast medium. The role of autonomic reflexes in the pathogenesis of this phenomenon is unclear. Although the muscarinic antagonist atropine is often administered prophylactically before coronary angiography to reduce the likelihood of sinus bradycardia and vasovagal reactions, its influence on ventricular arrhythmias in this setting has not been established. This case-control trial studied 648 patients undergoing coronary arteriography to investigate this issue. Eleven case subjects (those with ventricular tachyarrhythmia) were identified. Control subjects (those without ventricular tachyarrhythmia) were matched for baseline heart rate (+/- 6 beats/min), age (+/- 10 years), sex and calendar year of procedure using a 1:3 sampling ratio. All 26 potential clinical, anatomic and hemodynamic covariates were statistically similar between groups. Ventricular tachyarrhythmias were more likely to occur after selective right coronary injection (odds ratio 15.1, p = 0.0008) but not after multiple contrast injections (odds ratio 0.918, difference not significant). Most importantly, atropine sulfate was administered prophylactically to 18 of 33 control subjects (55 +/- 9%) but only 1 of 11 cases (9 +/- 9%), generating a significant odds ratio of 12.0 (p = 0.02). Thus, the odds of experiencing sustained ventricular tachyarrhythmias during coronary arteriography may potentially be reduced 12-fold by prior administration of atropine, even in patients with normal baseline heart rates.

Comparison of low osmolality ionic (ioxaglate) versus nonionic (iopamidol) contrast media in cardiac angiography

A double-blind randomized study was performed in 60 patients to compare the electrocardiographic and hemodynamic changes induced during cardiac angiography by 2 contrast media with relatively low osmolality. Ioxaglate meglumine sodium, an ionic dimer contrast medium, was compared with iopamidol, a nonionic compound. Of the 30 patients who received ioxaglate, 13 (43%) experienced a mild to moderate adverse reaction to the contrast media, while only 2 of the 30 patients (7%) in the iopamidol group had similar side effects (p less than 0.005). Significant prolongations of the QT intervals occurred with the ioxaglate injections. The QT intervals increased from 402 +/- 46 to 442 +/- 59 ms (p less than 0.001) with the right coronary artery injection and similar changes were observed after the left coronary artery injection and left ventriculography. Significant ST-segment and T-wave amplitude changes also occurred in the ioxaglate group. With iopamidol injections, there were no significant changes in any of these parameters. After the left ventriculogram, there were similar decreases in the systolic arterial pressures in both groups (-14 +/- 10 mm Hg with ioxaglate and -21 +/- 9 mm Hg with iopamidol). The left ventricular end-diastolic pressures increased after the ventriculogram in both groups (5 +/- 5 vs 2 +/- 3 mm Hg with ioxaglate and iopamidol, respectively, 60 seconds after the injection). This report demonstrates that mild to moderate adverse reactions, QT-interval prolongations, ST and T-wave changes were significantly greater during coronary angiography with ioxaglate when compared with iopamidol.(ABSTRACT TRUNCATED AT 250 WORDS)

Contrast media-related complications during cardiac catheterization using Hexabrix or Renografin in high-risk patients

Contrast media may lead to adverse reactions during cardiac catheterization. Hexabrix has less hemodynamic and electrophysiologic effects than Renografin-76. To assess relative complication rates using these agents, 82 patients with heart failure or "unstable" ischemic syndromes and undergoing catheterization were prospectively randomized to receive either Hexabrix or Renografin. Clinical diagnoses, hemodynamics before contrast media administration, left ventricular ejection fraction, case duration, contrast volume and cine film quality were similar in the 2 groups. The condition of 1 patient assigned to receive Renografin was deemed too unstable and Hexabrix was safely used. In the other patients, a total of 17 adverse reactions occurred (7 before administration of contrast and thus unrelated: 4 Hexabrix- and 3 Renografin-assigned patients, difference not significant). Three contrast-induced adverse reactions were considered minor (Hexabrix 2, Renografin 1, difference not significant). Severe adverse reactions requiring intervention, such as pulmonary edema and hypotension, were more frequent in patients who received Renografin (6 of 38, 16%) as compared with Hexabrix (1 of 43, 2%) (p less than 0.05). It is concluded that in high-risk patients undergoing cardiac catheterization, Hexabrix is tolerated better than Renografin and should be considered for routine use.