Combination Gadolinium Angiography and Intravascular Ultrasound Study for Coronary Artery and Graft Assessment

Abstract

Contrast allergies may range from minor to life-threatening, such as Stevens-Johnson syndrome, and pose a challenge to obtaining timely coronary angiography. Here, we present a complex patient with a history of 5-vessel coronary artery bypass grafting and end-stage renal disease who required native coronary and bypass graft angiogram prior to listing for renal transplant. Due to a history of iodinated contrast-induced Stevens-Johnson syndrome, this patient was unable to undergo standard angiography. This diagnostic challenge was overcome with the safe, hybrid approach of using intravascular ultrasound to guide minimal administration of gadolinium contrast media to obtain a complete angiography.

Introduction

Despite the advancements in noninvasive diagnostic testing for coronary artery disease (CAD), such as cardiac positron emission tomography stress myocardial perfusion imaging, invasive coronary angiography remains the standard, especially after coronary artery bypass grafting (CABG). Approximately 0.1% of patients who receive iodinated contrast media during radiographic studies experience an allergic reaction, most commonly erythema and urticaria.¹ These patients may be pretreated with steroids and antihistamines prior to receiving iodinated contrast to prevent future reactions. Rarely, some may develop Stevens-Johnson syndrome (SJS), a serious and potentially life-threatening desquamation reaction, when exposed to contrast media. Attempts to desensitize a patient to a medication known to cause SJS are generally contraindicated.² There exists a case report of using multiple rounds of IVIG and oral prednisone taper to diminish the SJS response after iodinated contrast was used in coronary angiography.³ Gadolinium-mediated coronary angiography is a novel approach when iodinated contrast media is contraindicated,⁴ such as in cases of contrast-associated angioedema, severe hyperthyroidism, or when there is a critical shortage of contrast. However, gadolinium contrast use in patients with end-stage renal disease (ESRD) is not without risks, historically nephrogenic systemic fibrosis (NSF). Once a grave concern with certain forms of gadolinium agents, a recent systematic review and meta-analysis have revealed that in lowest-risk group II gadolinium agents (ie, gadobenate dimeglumine and gadoterate meglumine), the estimated risk of NSF is likely <0.07% in patients with ESRD.⁵

We present the case of a patient with a complex medical history including prior 5-vessel CABG, ESRD, and contrast-induced SJS who was referred for coronary angiography as part of renal transplantation evaluation. Here, we discuss a unique, hybrid approach to safely perform a high-quality diagnostic coronary and bypass graft angiography using a minimal amount of gadolinium contrast directed by intravascular ultrasound (IVUS).

Case presentation

The patient is a 40-year-old man with a history of premature CAD with 5-vessel CABG 6 years prior, ESRD on hemodialysis via an upper extremity arteriovenous fistula, and contrast-induced SJS undergoing evaluation for renal transplant. He had an abnormal single photon emission computed tomography stress test with mildly-to-moderately reduced perfusion in the apical anterior, apical septal, and true apical segments, as well as in the basal to midinferior segments during stress, which partially resolved at rest. He was referred for a coronary angiogram. The patient previously had 4 fistulograms with the standard iodinated contrast media, and after each exposure, he experienced a crescendo of worsening reactions. The last reaction occurred 3 years prior; he developed severe blistering of the mouth, upper airway, and genitalia, requiring hospitalization and prolonged treatment with systemic steroids for SJS. He did not receive any premedication prior to the fistulograms. Allergy and immunology specialists recommended that iodinated contrast media be strictly avoided given concerns the reactions would become life-threatening. After interdisciplinary specialist meetings, it was decided to employ a hybrid approach to coronary angiogram using IVUS and the minimum amount of gadolinium contrast.

Ultrasound-guided femoral access was obtained. To identify the aortic anastomotic site of the venous graft, a 6F Judkins Right 4 guide catheter (Cordis) was delivered to the ascending root over a 0.035-inch wire. Instead of contrast to identify the ostium, we studied the guide motion and ability to advance the coronary wire under fluoroscopy to assess graft engagement. This approach allowed us to engage the saphenous vein grafts to the obtuse marginal (OM) and posterior left ventricular arteries under fluoroscopy (Figure 1). The OPTICROSS HD IVUS catheter (Boston Scientific) was then delivered over the 0.014-inch wire into the native vessel, and then pulled back to demonstrate a patent graft without significant atherosclerosis. Both native coronary arteries were wired and imaged with IVUS beyond the anastomosis.

Figure 1.

Placement of Coronary wire in to coronary and saphenous vein graft. (A) Coronary wires placed in the obtuse marginal branches followed by intravascular ultrasound (IVUS) imaging to evaluate the vessels. (B) IVUS catheter over the coronary wire to assess the saphenous vein graft to the obtuse marginal artery.

The 6F XB 3.5 guide (Cordis) was then used to engage the left main coronary artery. A single-shot angiogram using GADOVIST 1.0 (gadobutrol, Bayer Inc) was performed to define the arterial anatomy prior to IVUS evaluation. Then, the left anterior descending and high OM were wired with the coronary guide wire, followed by IVUS (Figure 2). Finally, the left internal mammary artery graft was engaged using 0.014-inch wire; a single-shot angiogram was performed (Figure 3). By the end of the procedure, all saphenous vein grafts, the left internal mammary artery graft, left main coronary, OM, and circumflex arteries were confirmed to be patent on IVUS. A total of 15 mL of gadolinium contrast medium was used for the procedure. Subsequently, he underwent same-day, postangiogram hemodialysis and was monitored overnight. There were no complications; the patient was later listed for and underwent a successful renal transplantation.

Figure 2.

Intravascular ultrasound image demonstrating patency of one of the saphenous vein grafts (SVG) to the obtuse marginal artery (OM).

Figure 3.

Angiography of LIMA-LAD bypass with gadolinium contrast. LIMA, left internal mammary artery; LAD, left anterior descending artery.

Discussion

Based on a literature review, this is the first case to date describing the use of IVUS and gadolinium contrast angiography in a patient with ESRD and iodinated contrast–related SJS. The development of increasingly severe allergic reactions, including SJS, from prior exposure to iodinated contrast presented an unacceptable risk to this patient. Other alternatives for contrast media are available, such as carbon dioxide; however, its use is contraindicated in supradiaphragmatic arterial studies given the risk of cerebral air embolism.⁶ Gadolinium-based contrast agents carry an extremely small, estimated risk of NSF in patients with ESRD. By limiting the volume of gadolinium media used with our hybrid approach, this patient underwent an angiogram without complication.

The concept of a zero-contrast percutaneous coronary intervention has been described in patients with severe renal impairment. This has been used safely with the treatment of even complex coronary lesions.⁷ Several techniques from these reports were employed to minimize contrast use in this case. When proper vessel engagement was confirmed, we utilized intracoronary imaging via IVUS not only to evaluate the arterial lesions but also to confirm the optimal position to minimize contrast use when performing the gadolinium angiogram (15 mL was used for the entire case).

Despite multiple barriers to angiography, this patient underwent the requisite evaluation for renal transplant safely due to the hybrid approach of using IVUS to minimize gadolinium contrast administered. This is the first reported case describing a hybrid approach for a zero iodinated contrast coronary graft angiography for a patient with ESRD and severe iodinated contrast allergy. This case demonstrates an expansion of the techniques for CAD evaluation without iodinated contrast to now include patients with complex anatomy following CABG.