CMR Reveals Undetected Cardiac Disease in Rheumatology

Connective tissue disorders (CTDs) represent a diverse and challenging variety of rheumatologic diagnoses that impact many parts of the body. Although targeted treatments for CTDs have improved symptoms and decreased mortality rates in patients with rheumatologic disease, these patients are still not living as long as the general population. This is due to non-rheumatologic coexisting diseases, in particular, heart and vascular disease.

Using magnetic resonance imaging or more specifically, cardiovascular magnetic resonance (CMR), clinicians can uncover unseen cardiac disease without requiring invasive or surgical methods or radiation seen with CT scanning or coronary artery angiography (also know as cardiac catheterization). CMR is capable of providing measurable, valid data with regards to many aspects of the heart muscle, function and most importantly with respect to CTDs, cardiac tissue characteristics and vascular structures, which are often involved in progressive CTDs.

A group of experts from throughout the world have assembled The International Consensus Group on CMR in Rheumatology and have developed a set of recommendations to standardize the indications for use of CMR across the different disease states under the umbrella of CTDs as well as protocols, terminology for reporting and criteria for diagnosis utilizing CMR. The consensus group is looking to the future with having developed a research agenda to address changes in this evolving discipline.

Writing in the April 27 online issue of the International Journal of Cardiology, the group made the following observations and recommendations: 

1.      Connective tissue diseases increase the likelihood of cardiovascular disease through systemic inflammation, early onset coronary and peripheral vascular disease, fibrosis of the heart muscle itself and through the use of treatments that are sometimes toxic to the heart.

2.      CMR is an emerging alternative to echocardiography, nuclear imaging and angiography, which are the standards at this time.

3.      It is the noninvasive nature of CMR and the avoidance of ionizing radiation that make it appealing as a diagnostic tool.

4.      Patients who cannot undergo CMR include those with permanent pacemakers, automated implantable defibrillators or ferromagnetic aneurysm clips. It is further recommended to avoid CMR in the first trimester of pregnancy.

5.      Consensus indications for use of CMR in CTDs include:  diagnosis of cardiovascular disease acuity, myocarditis, myocardial infarction, vasculitis, myocardial perfusion, myocardial fibrosis and infiltration, microvascular disease, coronary artery evaluation, assessment of ventricular function, constrictive pericarditis, evaluation of unexplained heart failure and assessment of valvular heart disease.

6.      Used for the detection of myocardial ischemia and fibrosis, stress testing with CMR is superior or equal to stress electrocardiogram, stress echocardiography, and nuclear stress in the areas of spatial resolution, artifact generation, operator dependency and radiation delivered. High cost and less availability limit the access to stress CMR.

7.      X-ray coronary angiography and endomyocardial biopsy can only be used in specific clinical indications. This is important to know because patients with CTDs usually have silent or oligosymptomatic cardiac presentation. And, 25-30% of patients with inflammatory myopathies and SLE cannot always be detected by echocardiography.  Neither echocardiography nor nuclear imaging is capable of detecting subendocardial vasculitis with great accuracy.

Summary and Conclusions:

Connective tissue diseases represent a wide variety of rheumatologic disorders that affect many organ systems. CVD assessment in patients with CTDs is now regarded as standard practice. While advances in treatment have led to better quality of life and less CTD-related death, unrecognized or improperly treated cardiovascular disease may continue to shorten patients life expectancy.  Prompt diagnosis of cardiovascular complications is essential for disease management.

Current standards for diagnosis of cardiovascular disease include echocardiography, nuclear imaging and angiography, which are less sensitive at detecting many of the cardiovascular manifestations of CTDs while, in many cases, subject the patient to high doses of radiation and or invasive procedures when compared to CMR. CMR represents a low risk highly sensitive tool to detect cardiovascular disease in patients with CTDs in an effort to determine risk and optimize management whether in conjunction with current modalities or as an alternative to them.

The International Consensus Group on CMR in Rheumatology suggests that CMR be considered as a diagnostic tool for CTDs in the following cases:

 (Continued on next page.) 

The International Consensus Group on CMR in Rheumatology suggests that CMR be considered as a diagnostic tool for CTDs in the following cases:

 1.      To evaluate patients with acute or persistent typical or atypical cardiac symptoms and normal routine noninvasive evaluation 2.      To evaluate the possibility of silent myocardial inflammation in inflammatory myopathies with normal routine noninvasive evaluation 3.      To clarify the myocardial status in scleroderma with acute symptoms and normal routine noninvasive evaluation 4.      To evaluate the possibility of myocardial and/or vascular inflammation in primary or secondary vasculitis 5.      To evaluate any CTD patient with acute LV dysfunction 6.      To evaluate any CTD patient with recent onset of RBBB, LBBB, atrioventricular block or evidence of arrhythmia with or without positive routine noninvasive evaluation 7.      To clarify the myocardial status in technically inconclusive routine noninvasive evaluation or in case that the results of this evaluation cannot explain the patients' symptoms and signs 8.      When, although the systemic disease appears under control, the patient has typical or atypical cardiac symptoms and noninvasive cardiac evaluation is negative 9.      If the patients' symptoms suggest to commence or modify cardiac treatment and the routine noninvasive evaluation is normal or doubtful 10.   To assess stress myocardial perfusion in CTDs, unable to exercise, with poor acoustic window or increased breast size; additionally, in young CTDs in whom repeated radiation should be avoided 11.   As a gatekeeper for X-ray coronary angiography in CTDs with cardiac symptoms and mild or abnormal echocardiographic findings 

References:

Sophie I Mavrogeni, George D Kitas, et al.

"Cardiovascular Magnetic Resonance in Rheumatology:  Current Status and Recommendations for Use,"

International Journal of Cardiology. Aug. 27, 2016. http://dx.doi.org/10.1016/j.ijcard.2016.04.158