Coronary anatomy: Difference between revisions

=Left ventriculography=

Left ventriculography provides information about global and segmental left ventricular function and mitral regurgitation, and some other abnormalities (ventricular septal defect, hypertrophic cardiomyopathy, left ventricular thrombi)<cite>Baim</cite>.  

''Technique''

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The large amount of contrast that is needed in short time, is delivered by a pigtail catheter with multiple side holes. The RAO 30° projection is used without magnification. The catheter is placed on the aortic valve with a guidewire, retracted a few centimeters in the catheters. After pushing the pigtail on the valve until bending, it is retracted slowly while being rotated clockwise, untill passing into the left ventricle (figure 1<cite>Hartcatheterisatie</cite>). The optimal catheter position is midcavitary. About 35 ml of contrast is delivered at 10ml/second at a PSI of maximal 1000 at RAO 30° and LAO 60°. Left ventriculography can be performed with normal quiet breathing (in LAO, the diaphragm can be obstructive during expiration).  

''Interpretation''

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The left ventriculogram is analysed qualitatively on a sinus beat following a previous sinus beat since ectopic of postectopic beats give a false impression of ventricular function. Overall ventricular function is described. In RAO view, the anterolateral, apical, inferior and posterobasal segment can be seen, in LAO view the posterolateral, lateral and septal segments (figure 1). The degree of mitral regurgitation can be estimated.  

''Complications''

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It is normal for the patient to experience a hot feeling due to powerful vasodilatation of the contrast. Ventricular extrasystoles occur frequently but also ventricular tachycardia or ventricular fibrillation can occur. The pigtail can be placed under chordae (catheter close to inferior wall). If it is placed under the papillary muscles with a side hole firmly against the endocardium, deposition of contrast material within the endocardium and myocardium can occur, leading rarely to myocardial perforation. A possible complication that can lead to death is the injection of air (air embolism). If the catheter is placed in the left ventricular outflow tract, a left anterior fascicular block can occur, leading to complete heart block in pre-existing right bundle branch block and left posterior fascicular block.  

Figure 1

[[File:TimeOut_figure1.png]]

Figure 2

[[File:TimeOut_figure2.gif]]

#Anterobasal  

#Lateral  

#Septal

Figure 3

[[File:TimeOut_figure3.gif]]

=Shock=