Cardiac diagnostic imaging: understanding angiography

Reviewed by Dr. J.M. Montero-Cabezas, Interventional Cardiology Department, Leiden University Medical Center (LUMC)

Cardiac diagnostic imaging is a critical component of modern cardiovascular medicine. These tests are vital to healthcare providers, as they reveal symptoms and allow for the diagnosis and management of heart-related ailments. In its early practice, cardiac imaging mainly consisted of catheterization and angiography. However, in recent decades, testing has evolved to become less invasive and more sophisticated. By evaluating the strengths and applications of each form of cardiac diagnostic imaging, tests can be applied more practically to patients to manage their conditions. This article will detail techniques, applications, and limitations of angiography and other cardiac diagnostic imaging modalities. Additionally, it will provide comprehensive knowledge of emerging innovations that will enhance the ability to identify and treat cardiovascular disorders. (1,3)

What is cardiac diagnostic imaging?

Cardiac diagnostic imaging refers to the variety of test procedures used to take pictures of the heart and surrounding anatomy. Overall, heart imaging tests are used to better understand the health of a patient. This can involve screening for early detection of heart ailments, the diagnosis of heart conditions, and monitoring to evaluate the effectiveness of treatments. Diagnoses may include arrhythmia, heart valve disease, coronary artery disease, heart attack, and heart failure. (1,3)


Exploring types of cardiac imaging methods

There are a range of methods employed by healthcare providers to capture cardiac images. Common types of heart scanning include:

  • Coronary Angiogram 

  • Echocardiogram (echo)

  • Cardiac MRI

  • Cardiac computed tomography (CT)

  • Stress Tests

  • Single-photon emission commuted tomography (SPECT)

  • Cardiac positron emission tomography (PET)

  • Multigated acquisition scan (MUGA)

Cardiac imaging - Wikipedia

The administration techniques, as well as the orientation of the heart, image resolution, and angle selection vary between these tests which may increase the difficulty of the diagnosis, but they all are used to accomplish the similar objectives. Factors such as the clinical indication, patient characteristics, and availability of resources influence which heart imaging modality is selected. In some cases, a combination of these modalities may even be used to better understand the state of the heart. (1)

What are the roles of CT Scans and MRI in cardiac imaging?

Cardiac magnetic resonance imaging (MRI) is a diagnostic that produces both still and moving images of the heart. This is another type of non-invasive heart scanning, performed with a computer using magnetic and radio frequencing. With the ability to capture movement, they allow for the detection of abnormal blood flow, tumors, diseases, cardiac hypertrophy, and other heart ailments.

Cardiac CT technology is a type of cardiac imaging that evaluates the coronary vessels and other adjacent structures to identify blockages, blood clots, tumors, and aneurysms, as well as assess the risk of developing cardiovascular disease. What sets this technique apart from an MRI is that it uses small amounts of radiation instead of magnets. This cardiac imaging procedure is non-invasive and uses X-rays to view the heart and its surrounding structures. (2)

CT Scans and MRIs are part of the standard of care to diagnose cardiac conditions. However,

the cost of these procedures is very high and oftentimes take a long-waiting list.


Deep dive into coronary angiography

Cardiac imaging tests and treatments are complex, and application varies widely among patients. Angiography is an invasive form of cardiac imaging using catheterization that can be combined with other tests and treatments. Before undergoing an angiography, it is pivotal to understand the process, risks, and objectives of the procedure. 


 The Procedure of Angiography

Coronary angiography is often administered using cardiac catheterization. The process takes only 30-60 minutesnvasive. During the procedure, local anesthesia is applied at the puncture site and access is established either through the radial or femoral artery. Catheters and wires are then introduced into the arterial system, and a contrast agent is injected into the coronary arteries. This process highlights the coronary arteries on X-ray images, allowing doctors to identify any blockages or narrowing of arteries. (4)

            Cardiac Angiography

Risks and Advantages of Angiography

Angiography and cardiac catheterization are more invasive than other heart imaging tests, and because of this, they come with certain risks. A possibility always remains for the following complications to occur:

  • Injury to a coronary artery

  • Reaction or kidney damage from contrast dye

  • Irregular heartbeat

  • Cardiac tamponade

  • Low blood pressure

  • Bleeding, blood clots

  • Infection

  • Heart attack

  • Stroke. 

Still, the risk of this procedure remains very low– less than 1% experience major complications. Furthermore, it gives the healthcare providers life-saving information to analyze the heart’s condition and determine the best form of treatment. Typically, a coronary angioplasty also involves the placement of a stent– a tubular, expandable metal piece of mesh. The primary objective of coronary stents is to keep the artery open and prevent narrowing or occlusion post-treatment. (5)

Preparing for your appointment

Prior to an angiography, your healthcare provider will explain the process and its risks, and you will be required to sign a consent form in front of a witness. It is important to let your provider know of any allergies, medications, past reactions to materials being used, or if you may be pregnant. Before your test, you should not consume food or beverages for 6-8 hours, and you may be asked to spend the night at the hospital. (5)

Interpreting and responding to cardiac imaging results

In some forms of heart scanning, the images can be read directly, but others require reconstruction to form 3D images. Measurements of blood flow, oxygen levels, and biopsies must also be interpreted to diagnose certain heart conditions. Interpretation of and terminology used to indicate results vary by modality. With an angoigram, “normal” results indicate that no visible disease or luminal irregularities are present. Abnormal results take the form of a diagnosis of a heart condition, and allow the healthcare provider to plan treatment. (1)

Although angiography and stent placement have the potential to save lives, risk of future complications, such as stent restenosis, fracture, or thrombosis must be considered. Because of this, it is crucial to follow the clinical check-ups recommended by specialists after undergoing these procedures. 

To mitigate the risk of further cardiovascular issues or stent complications, we encourage you to check out our blog and read about Post Coronary Stent Care.

In the event of symptoms indicating stent failure, coronary angiography may be used to ensure the stent is working properly. Read about How to recognize symptoms of sent failure.

The future of cardiac imaging: the NIMBLE Diagnostics System

Advancements in technology are continually being developed to diagnose cardiac ailments in a non-invasive manner. Methods of angiography and heart imaging have already evolved significantly beyond their early practices. However, the technology currently available to cardiologists lacks the capacity for non-invasive monitoring of coronary stents. Consequently, many patients do not receive the diagnoses on time, either due to the expense and invasiveness of coronary angiography, or when they do not exhibit any apparent symptoms. (2)

NIMBLE Diagnostics is committed to the development, testing, and launch of its innovative NIMBLE System, engineered to offer clinicians objective insights on the status of coronary stents. Using state-of-the-art microwave imaging technology, this device can assess stents in both symptomatic and asymptomatic patients without resorting to invasive angiography. This technology is quick, cost-effective, and will be widely accessible for patients. Unlike with current practices, patients will not require hospitalization, as the system can be easily accessed from a clinic. The NIMBLE System has the capacity to detect stent malfunctions before they escalate

into serious complications such as stroke, heart attack, or sudden death.

TECHNOLOGY - Nimble Diagnostic


Cardiac imaging has undergone significant evolution, offering healthcare providers increasingly sophisticated tools for diagnosing and managing cardiovascular disorders. With ongoing advancements in technology, the future of cardiac imaging holds promise for further enhancing patient care and outcomes.

The information published in this Blog article, or in NIMBLE DIAGNOSTICS website, is provided for information purposes only and does not and cannot be considered as a consultation, treatment, therapy, or medical or clinical prescription, nor is it a substitute for treatment, diagnosis, therapy, or supervision by a healthcare professional. The information published is neither intended to be used as a guide and should not serve nor be used as an exclusive orientation for the healthcare professionals to make decisions about the treatment and therapy of their patients, nor does it replace the healthcare professionals’ criteria. NIMBLE DIAGNOSTICS makes no warranties as to the accuracy, suitability, or completeness of the information provided, and shall not be held responsible for any decisions made based on the information provided on this Blog article, NIMBLE DIAGNOSTICS website or any other websites linked or referenced in NIMBLE DIAGNOSTICS website.

Sources 1 2 3 4,Cardiac%20catheterization%20is%20used%20to%20study%20the%20various%20functions%20of,or%20vein%20into%20the%20heart. 5

Image Citations 1 2