The study was conducted on 42 patients including both pediatric (33 patients) and adult patients (9 patients). The patients were referred from the cardiology department, Kasr El Aini Hospital , the Children Hospital (Abu El Reesh) , Egypt and Hospital of Gonesse ,France . Their ages range from 5 months to 32 years and mean 10.1+7.4 (13 females and 29 males). 28 patients were submitted to both echocardiographic examination and MRI study. CTA was performed in 11 cases.
A Philips Gyroscan Intera (1.5 T) super conducting magnet was used in the radiology department, Kasr ElAini Hospital, Cairo University.
A General Electric Optima MR 450w 1.5 T conducting magnet was used in the radiology department, Hospital of Gonesse ,France
A convenient sample of the patients was included in the study to cover a wide range of the congenital heart lesions. Patients were screened for contraindications to MR imaging. Absolute contraindications include the presence of a pacemaker, cardiac defibrillator, or other conductive metallic devices. A relative contraindication is the presence of a new coronary stent placed within 6 weeks prior to the MR study. There were no patients with contraindications for the MR imaging.
The imaging protocol used is standard for all age groups with MRI flowmetry not done for 8 pateitns and CE-MRA not done for 7 patients
Ventricular volumes were calculated for all successful 38 examinations of patients .
MRI proves to be a very useful technique for the evaluation of both the intra and extra cardiac congenital heart lesions and is also the gold standard for ventricular function assessment.
Management of patients with congenital heart disease relies heavily on imaging, with echocardiography remaining the mainstay for diagnosis and follow-up.
Echocardiography combines the benefit of being able to accurately assess anatomy and function with portability and ease of use. However, echocardiography is limited by acoustic windows, provides poor images of the distal vasculature, and is user-dependent.
Cardiovascular imaging is becoming an important tool for both the initial diagnosis and follow-up of children and adult patients who are subjected to surgical or cardiac catheterization interventional procedures. Its main role is an adjunct to echocardiography, rather than a replacement. In situations where echocardiography can not answer all the clinical questions, cardiovascular MR can provide an accurate, non invasive method of imaging patients with congenital heart disease. CMRI has the potential of assessing intracardiac, myocardial and extracaridac vasculature. It plays a crucial role in sequential segmental analysis of cardiac chambers and great vessels and characterizing the morphology of cardiac chambers in cases of complex congenital cardiopathies and situs ambiguous. We can also never ignore the important diagnostic role of MRI in both the ischaemic and non ischaemic cardiomyopathies. The value of MRI is now well recognized as an optimal imaging modality for assessing and monitoring a wide variety of diseases of the great vessels and surrounding structures. It can even represent a viable alternative to cardiac catheterization in the future.
Cardiovascular MR also represents the best available in vivo method for quantification of ventricular function and vascular flow. The use of velocity-encoded phase-contrast MR allows accurate, non invasive quantification of blood flow and pressure gradients. Finally, MR allows the assessment of coronary anatomy, perfusion and scar. Thus, MR provides a “one-stop” imaging modality, allowing assessment of anatomy, function and perfusion.
Multi-detector row computed tomography has also been used widely for the evaluation of the thoracic vascular structures and quantification of ventricular function. However, there are two important issues, which only CT has to face, the necessity to administer iodinated contrast and the high radiation doses of the multislice CT machines. Thus, CT should be considered as being a minimally invasive rather than non-invasive technique. This increases the hazard of x-ray exposure to children who can be exposed to more than one cardiac catheterization procedure. MRI can totally replace CT angiography and spare the children the hazards of contrast injection and exposure to radiation with all its magnificent potentials of evaluating both intracardiac and extracardiac anatomy, ventricular functions, hemodynamic assessment for blood flow volume (Qp/Qs), peak velocities and pressure gradients all in one examination.
We also hope that in the near future MR guided cardiac catheterization will be possible in all patients without x-ray back up. The reduced x-ray exposure, better anatomical visualization, and improved accuracy of hemodynamic information should make this the method of choice for diagnostic cardiac catheterization. With further developments in catheters and devices making them MR compatible, MR guided cardiac catheterization will have a role in interventional procedures.
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