In the last years, cardiac MRI techniques have progressively improved. No other noninvasive imaging modality provides the same degree of contrast and temporal resolution for the assessment of cardiovascular anatomy and pathology. Contraindications MRI are the same as for other magnetic resonance techniques.
The primary advantage of MRI is extremely high contrast resolution between different tissue types, including blood. Moreover, MRI is a true 3 dimensional imaging modality and images can be obtained in any oblique plane along the true cardiac axes while preserving high temporal and spatial resolution with precise demonstration of cardiac anatomy without the administration of contrast media.
Due to these properties, MRI can precisely characterize cardiac function and quantify cavity volumes, ejection fraction, and left ventricular mass. In addition, cardiac MRI has the ability to quantify flow (see flow quantification), including bulk flow in vessels, pressure gradients across stenosis, regurgitant fractions and shunt fractions. Valve morphology and area can be determined and the severity of stenosis quantified. In certain disease states, such as myocardial infarction, the contrast resolution of MRI is further improved by the addition of extrinsic contrast agents (see myocardial late enhancement).
A dedicated cardiac coil, and a field strength higher than 1 Tesla is recommended to have sufficient signal. Cardiac MRI acquires ECG gating. Cardiac gating (ECGs) obtained within the MRI scanner, can be degraded by the superimposed electrical potential of flowing blood in the magnetic field. Therefore, excellent contact between the skin and ECG leads is necessary. For male patients, the skin at the lead sites can be shaved. A good cooperation of the patient is necessary because breath holding at the end of expiration is practiced during the most sequences.

See also Displacement Encoding with Stimulated Echoes.
For Ultrasound Imaging (USI) see Cardiac Ultrasound at Medical-Ultrasound-Imaging.com.

See also the related poll results: 'In 2010 your scanner will probably work with a field strength of' and 'MRI will have replaced 50% of x-ray exams by'

Cine sequences used in cardiovascular MRI are collection of images (usually at the same spatial location) covering of one full period of cardiac cycle or over several periods in order to obtain complete coverage.
The pulse sequence used, is either a standard gradient echo pulse sequence, a segmented data acquisition, a gradient echo EPI sequence or a gradient echo with balanced gradient waveform. In cardiac gating studies it is possible to assign consecutive lines either to different images, yielding a multiphase sequence with as many images as lines, or the lines are grouped together into segments and assigned to the same image. The overall time to acquire such a segment has to be small compared to the RR-interval of the cardiac cycle, i. e. 50 ms, and hence contains typically 8 to 16 image lines.
This strategy is called segmented data acquisition, and has the advantage of reducing overall imaging time for cardiac images so that they can be acquired within a breath hold, but obviously decreasing the temporal resolution of each individual image. This method shows dynamic processes, such as the ejection of blood out of the heart into the aorta, by means of fast imaging and displaying the resulting images in a sequential-loop, the impression of a real-time movie is generated. Ejection fractions and stroke volumes calculated from these cine MRI images in different cardiac axes have been shown to be more accurate than any other imaging modality.

See also Cardiac Gating.

Contrast enhanced MRI is a commonly used procedure in magnetic resonance imaging. The need to more accurately characterize different types of lesions and to detect all malignant lesions is the main reason for the use of intravenous contrast agents.
Some methods are available to improve the contrast of different tissues. The focus of dynamic contrast enhanced MRI (DCE-MRI) is on contrast kinetics with demands for spatial resolution dependent on the application. DCE-MR imaging is used for diagnosis of cancer (see also liver imaging, abdominal imaging, breast MRI, dynamic scanning) as well as for diagnosis of cardiac infarction (see perfusion imaging, cardiac MRI). Quantitative DCE-MRI requires special data acquisition techniques and analysis software.
Contrast enhanced magnetic resonance angiography (CE-MRA) allows the visualization of vessels and the temporal resolution provides a separation of arteries and veins. These methods share the need for acquisition methods with high temporal and spatial resolution.
Double contrast administration (combined contrast enhanced (CCE) MRI) uses two contrast agents with complementary mechanisms e.g., superparamagnetic iron oxide to darken the background liver and gadolinium to brighten the vessels. A variety of different categories of contrast agents are currently available for clinical use.
Reasons for the use of contrast agents in MRI scans are:
Common Indications:
Brain MRI : Preoperative/pretreatment evaluation and postoperative evaluation of brain tumor therapy, CNS infections, noninfectious inflammatory disease and meningeal disease.
Spine MRI : Infection/inflammatory disease, primary tumors, drop metastases, initial evaluation of syrinx, postoperative evaluation of the lumbar spine: disk vs. scar.
Breast MRI : Detection of breast cancer in case of dense breasts, implants, malignant lymph nodes, or scarring after treatment for breast cancer, diagnosis of a suspicious breast lesion in order to avoid biopsy.

For Ultrasound Imaging (USI) see Contrast Enhanced Ultrasound at Medical-Ultrasound-Imaging.com. See also Blood Pool Agents, Myocardial Late Enhancement, Cardiovascular Imaging, Contrast Enhanced MR Venography, Contrast Resolution, Dynamic Scanning, Lung Imaging, Hepatobiliary Contrast Agents, Contrast Medium and MRI Guided Biopsy.

(TrueFISP) True fast imaging with steady state precession is a coherent technique that uses a fully balanced gradient waveform. The image contrast with TrueFISP is determined by T2*//T1 properties and mostly depending on TR. The speed and relative motion insensitivity of acquisition help to make the technique reliable, even in patients who have difficulty with holding their breath.
Recent advances in gradient hardware have led to a decreased minimum TR. This combined with improved field shimming capabilities and signal to noise ratio, has allowed TrueFISP imaging to become practical for whole-body applications. There's mostly T2* weighting. With the used ultrashort TR-times T1 weighting is almost impossible. One such application is cardiac cine MR with high myocardium-blood contrast. Spatial and temporal resolution can be substantially improved with this technique, but contrast on the basis of the ratio of T2* to T1 is not sufficiently high in soft tissues. By providing T1 contrast, TrueFISP could then document the enhancement effects of T1 shortening contrast agents. These properties are useful for the anatomical delineation of brain tumors and normal structures. With an increase in SNR ratio with minimum TR, TrueFISP could also depict the enhancement effect in myoma uteri. True FSIP is a technique that is well suited for cardiac MR imaging. The imaging time is shorter and the contrast between the blood and myocardium is higher than that of FLASH.

See Steady State Free Precession.

The use of MR spectroscopy for acquiring functional activation of the brain.
There are two possible approaches:
In the first, localized spectra of brain water are acquired and subtle changes in these spectra reflect the biophysical water environment. Changes in T2 due to deoxyhaemoglobin concentration may be detected in this way. The disadvantages of poor spatial resolution are to some extent offset by the high signal to noise ratio SNR of the spectroscopic data.
An alternative approach is to use MR spectroscopy directly to detect metabolites that are altered by brain activation. These include lactate and glucose. Such experiments have inherently poor spatial and temporal resolution, but do give a direct indication of the metabolic response of the brain to functional activation.