Cardiac Imaging

The Cardiac Imaging Division is a joint program between Cardiology and Radiology. Cardiac imaging can give clinicians an early view of cardiovascular disease, the leading cause of death in the United States. Clinical applications include evaluation of coronary anatomy, diagnosis of aortic disease and evaluation of aneurysms, diagnosis of cardiac tumors, precise measurements of cardiac (ventricular) dimensions and function, and other advanced capabilities.

Advanced Cardiac Imaging
In 2005, Radiology entered an exciting new phase of imaging, cardiac CT. Cardiac CT allows non-invasive visualization and analysis of coronary arteries in less than 30 seconds. This speed is made possible by Radiology’s new 64-slice GE ultra fast CT scanner. The scanner can link imaging of the heart with the patient’s EKG, producing sub-millimeter imaging of the coronary arteries.

A typical cardiac CT exam produces over 1000 images, which can be reconstructed into 3D images of the heart and coronary arteries. This study helps clinicians decide whether to institute cholesterol-lowering statin therapy, or whether a patient should be referred to the cardiac catheterization laboratory for coronary artery stent placement.

Other advanced cardiac imaging modalities include cardiac MRI and nuclear cardiac imaging with detailed function evaluation, strain mapping, and perfusion. Cardiac PET is now clinically available for assessment of myocardial viability. Perfusion-sensitive MRI and cardiac CT, applied either as first tests or exams following nuclear scan or echo results, offer high-resolution definition of impaired blood supply and its consequences. These MR and CT tests may suffice to select cases that require full bypass or minimally invasive bypass, reducing the need for cardiac catheterization to direct interventions. Also, cardiac CT and/or interventional MRI could play a useful role in interventional catheterization by providing 3D visualization of blood vessels, yielding faster and safer procedures.

Research
The Cardiac Imaging Division performs clinical and basic research, especially in the area of angiogenesis (development of new vessels), which has applications for early cancer detection, improved treatment, and helping certain patients to avoid bypass surgery. We are investigating molecular imaging techniques that may potentially identify the molecular basis for disease in individuals through imaging, and target precise treatments. The Dartmouth Advanced Imaging Center will apply multi-disciplinary teams to problems in cardiovascular imaging.

Teaching
The Cardiac Imaging Division is very active in teaching. Residents, fellows, staff, and visiting professors are trained in both theory and practice, including how to decide when advanced tests are most useful and cost effective. Medical students, residents and fellows participate in lectures on the theory and practice of cardiovascular imaging. Advanced imaging capabilities in this field change constantly, so a student needs a solid foundation in the medical principles to keep pace with the technological advances. We aim to expand our teaching program to bring in even more top talent.

Drs. Tsapakos and Silas (Radiology) and Dr. Malenka (Cardiology) are involved with cardiac CT imaging. Dr. Vaccaro (Radiology) is consulted with pediatric cardiac cases. Dr. Pearlman (Cardiology and Radiology) and Dr. Tsapakos are involved with cardiac MRI.