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Angiography is performed to image the anatomical and structural details of the vascular system, including the cardiac chambers. Initially used for structural diagnosis of intravascular pathologies, angiography has been expanded to offer functional assessment and therapeutic options. This activity reviews the fundamental principles, indications, procedure technique, and complications of angiography, and also highlights the role of the interprofessional team in performing this procedure. Objectives: Review the indications for angiography. Describe the technique of angiography. Review the appropriate evaluation of the potential complications of angiography. Explain the importance of improving care coordination among interdisciplinary team members to improve outcomes for patients undergoing angiography. Access free multiple choice questions on this topic.

Medical imaging has benefitted from a boom in innovation in the past 50 years, which has allowed for rapid development in the field of interventional radiology. Angiography is used to image anatomical and structural details of the vascular system by detecting contrast injected into a blood vessel and projecting this on a series of x-rays to outline the inner vessel wall and show flow through the lumen. Starting as a diagnostic tool, angiography underwent a technological transformation over the last century and became a basis for interventional therapy as well. Angiography, initially a static two-dimensional record of the vasculature on screen-films, has evolved to a real-time two-dimensional display of the vasculature on television screens, and three-dimensional reconstruction from computed tomographic scans. Angiography has many advantages as it achieves real-time, dynamic imaging using a traditional imaging device - such as x-rays or computed tomography (CT), and it also offers therapeutic options at the time of initial diagnosis. Conventional angiography is invasive. In addition to providing therapeutic options, invasive angiography remains the gold standard in diagnosing most intravascular pathologies. Advances in imaging technology in the last three decades have expanded the scope of angiography to include non-invasive techniques using CT and magnetic resonance imaging technologies. In CT angiography (CTA), intravenous contrast is administered via a peripheral vein, and triple-phase CT is usually acquired. CTA is based on high-resolution CT data acquisition, with subsequent angiographic two or three-dimensional reconstruction. Advances and adaptations of CTA principles have been of immense benefit to patients with cardiovascular diseases. Whereas this is an excellent first-line investigation and offers information regarding the surrounding soft tissues, it is less useful in investigating blood flow to the extremities due to the small diameter. Interventional angiography provides higher resolution imaging and can detect changes in the small vessels.[1]

In CT angiography (CTA), intravenous contrast is administered via a peripheral vein, and triple-phase CT is usually acquired. CTA is based on high-resolution CT data acquisition, with subsequent angiographic two or three-dimensional reconstruction. Advances and adaptations of CTA principles have been of immense benefit to patients with cardiovascular diseases. Whereas this is an excellent first-line investigation and offers information regarding the surrounding soft tissues, it is less useful in investigating blood flow to the extremities due to the small diameter. Interventional angiography provides higher resolution imaging and can detect changes in the small vessels.[1] Magnetic resonance angiography (MRA): Clinical applications of MRA have become more salient for the patient and the clinician, especially in this era of rapid advances in imaging techniques. Magnetic resonance imaging (MRI) relies on the intrinsic magnetic trait of body tissues in an external magnetic field. It does not require ionizing radiation.[2] The details of CTA and MRA are beyond the scope of this review.

Though overall complications related to angiography remain low, the risk of complications following conventional angiography is higher in the elderly, patients with reduced cardiac reserve, calcified non-compliant arteries, renal disease, and multiple comorbidities. Minor Complications Bruising Nausea Pain at the puncture site Minor allergic reactions like rash, itch, or hives Transient deterioration in renal function Transient hot flushes or burning sensation Major Complications Significant bleeding, hematoma, or false aneurysm occur in <5% of angiograms, and 1 in 100 patients require overnight admission in the observation unit, while 1 in 500–1000 patients will require a second intervention or blood transfusion to correct the bleeding.[9] Significant allergic reaction (anaphylactoid reaction) Acute renal failure Contrast-induced nephropathy (CIN) is a substantial source of morbidity, which might require a brief period of renal replacement therapy. The essential preventive measures for contrast related complications include adequate peri-procedural hydration and use of minimal contrast volume.[9] Cigarroa et al. estimated the maximal acceptable contrast dose (MACD) using the following equation: (5 x bodyweight in Kg) divided by serum creatinine in mg/dl; up to a maximum volume of 300ml.[10] However, this formula is less useful in high-risk patients such as those with anemia, diabetes, heart failure, and cardiogenic shock, and it is infrequently used in clinical settings. Gurm et al. concluded that the ratio of contrast volume (CV) to the calculated creatinine clearance (CCC) of less than two is associated with a low incidence of CIN. In contrast, the risk of CIN is markedly increased when the ratio exceeds three.[11]

Successful angiography requires a collaborative interprofessional effort by the entire healthcare team. Registered nurses, nurse managers, and radiologic technologists with specialized critical care and technical skills are essential components of the angiography team. In the post-procedural period, case managers and social workers address the social circumstances peculiar to each patient and coordinate patients’ care with the clinicians.