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The technique used
to examine the heart depends on the question asked by those who requested
the autopsy.
Most of the
pathologists those who carry out autopsies will have learnt the
traditional method of opening the heart sequentially in the sequence of
blood flow starting at the inferior vena cava.
Removal
of the heart :
- The heart is
removed from the lungs by placing a finger through the transverse sinus
and then dividing the aorta and main pulmonary artery about 3cm above the
aortic valve.
- The pulmonary
veins can then be identified and divided.
- Finally the
superior vena cava is divided about 2cm above where the crest of the right
atrial appendage meets the vena cava, thus preserving the sinus node, and
the inferior vena cava is divided close to the diaphragm.
- The pathologist
now has an isolated but intact heart in which the venous connections have
been confirmed as normal.
Examination of
the heart: (Traditional Method) -
- Open the right
atrium by a cut from the inferior vena cava into the right atrial
appendage.
- Open the
tricuspid valve laterally down to the apex of the right ventricle.
- Cut from the
apex of the right ventricle through the pulmonary valve into the pulmonary
artery.
- Join two
pulmonary veins across the roof of the left atrium to view the inside of
the chamber.
- Cut through the
mitral valve orifice laterally down to the apex of the left ventricle.
- Cut from the
apex of the left ventricle up through its outflow tract into the aorta.
- There are two
variations in this final cut. It may be made through the anterior
cusp of the mitral valve itself or pass anteriorly, leaving a flap of
anterior wall of the ventricle hinged on an intact anterior cusp of the
mitral valve.
Advantage of
this method of examination:
It is possible
to examine the structure in detail.
Disadvantage of
this method of examination:
Destroy any understanding of the valve function ; Poorly
demonstrating the regional distribution of ischaemic myocardial damage and
ventricular shape and of having no correlation with the echocardiographic
planes used by clinicians.
Various other
techniques are followed the cardiovascular pathologists.
Some pathologists
routinely take a transverse 1cm thick slice across the ventricles before
opening the rest of the heart. Such slices allow accurate recording
of ventricular shape and of the distribution of ischaemic damage.
A general outline for examining the heart: CLICK
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