Page 481 - Cardiac Nursing

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C HAPTER 2 0 / Cardiac Catheterization 457
Other Possible Problems tion due to systolic constriction from encircling muscle bands or
MI, stroke, and HF are very rare complications after cardiac to coronary artery spasm is also observed, and its degree, distri-
catheterization. However, the nurse caring for patients after car- bution, and pattern are evaluated. If bypass grafts have been in-
diac catheterization should be aware of the signs and symptoms of jected, they are evaluated in the same manner for patency, flow
these complications. indices, and the condition of the perfused artery. Figures 20-12
and 20-13 show normal angiograms of the right and left coro-
nary arteries.
INTERPRETATION OF DATA Evaluation of myocardial function is an important part of the
evaluation of CAD. Patterns of ventricular contraction are evalu-
Table 20-2 lists normal ranges for some of the data gathered ated by ventriculography and estimated ejection fraction. The an-
during cardiac catheterization. The assessment of CAD involves teriolateral, apical, inferior, and posterobasal segments of the left
evaluation of the coronary vasculature and left ventricular ventricle can be examined in the RAO projection. In the LAO
function. projection, the basal septal, apical septal, apical lateral, and basal
The first step in evaluating the coronary arteriogram is to de- lateral segments can be evaluated. Regional contraction may be
termine whether the coronaries are unobstructed and free of le- classified as follows:
sions. Each major artery is traced along its entire length, and 1. Normal
branches and collaterals are noted and evaluated for irregularities 2.Mild hypokinesis—mild reduction in myocardial contraction
or narrowing. When occlusion is present, the degree of disease 3. Severe hypokinesis—more severe reduction in myocardial con-
and the suitability of the artery for revascularization are of pri- traction
mary concern. 4. Akinesis—total absence of wall motion in a discrete area
In addition to grading the occlusion, the condition of the dis- 5. Dyskinesis—disturbance causing abnormal movement of left
tal artery must be evaluated. The distal artery may be identified ventricular wall contraction
by antegrade or collateral flow, and its caliber and suitability as a 6. Aneurysm—paradoxical systolic expansion of a portion of the
recipient for bypass grafting are evaluated. Arteries with diffuse left ventricular wall
atherosclerotic plaquing and small distal targets are less suitable
for bypass grafting. The proximity of the occlusion determines The reversibility of myocardial contraction abnormalities is an
the amount of myocardium in jeopardy. A subjective evaluation important consideration in the decision for surgery and long-term
of the degree of arterial flow is made by observing the time re- prognosis. Improved function is more common with hypokinesis
quired for perfused arteries to fill and clear. Contrast medium than with akinesis or dyskinesis. The presence of collateral vessels
clears faster with higher flow rates. Intermittent luminal obstruc- and the lack of Q waves favor the reversibility of hypokinesis. 41
A B
■ Figure 20-12 Normal RCA shown in (A) RAO projection and (B) LAO projection. (Courtesy of Swedish
Medical Center, Seattle, Washington.)