Meta-analysis of adverse cardiovascular events associated with echocardiographic contrast agents

In October 2007, the Federal Drug Agency issued a black box warning for contrast agents used in patients undergoing echocardiography and restricted their use in patients with acute coronary syndrome, a decompensated heart, and respiratory failure. We performed a systemic review and meta-analysis to study the adverse effects of contrast agents used with respect to myocardial infarction and all-cause mortality. MEDLINE, EMBASE, BIOSIS, and Cochrane databases from inception to October 2009 were searched for studies that reported myocardial infarction and all-cause mortality after the use of contrast agents for echocardiography. A total of 8 studies were included in the present meta-analysis. A random-effect model was used, and between-studies heterogeneity was estimated with I². A total of 8 studies reported death as an outcome and only 4 reported myocardial infarction. The incidence of death in the contrast group was 0.34% (726 of 211,162 patients) compared to 0.9% (45,970 of 5,078,666 patients) in the noncontrast group. The pooled odds ratio was 0.57 (95% confidence interval 0.32 to 1.01, p = 0.05). The reported incidence of myocardial infarction in the contrast group was 0.15% (86 of 57,264 patients) compared to 0.2% (92 of 44,503 patients) in the noncontrast group. The pooled odds ratio was 0.85 (95% confidence interval 0.35 to 2.05, p = 0.72). Significant heterogeneity was seen among the studies. In conclusion, the cumulative evidence has suggested that the use of contrast agents for echocardiography is safe and not associated with a greater incidence of myocardial infarction or and mortality.