Hubert Petitier

Angiographic Explorations: Congenital Anomalies of the Coronary Arteries

With the development of coronary arteriography and myocardial revascularization surgery, and with advances in the surgical repair of congenital cardiopathies, there has been renewed interest in congenital anomalies of the coronary arteries.

Angiographic Explorations: Coronary Atheroma

Ventriculography and coronary arteriography are basic investigative techniques for use in patients with coronary atheroma. They indicate the site of stenoses, assess their severity and determine their operability, as well as sometimes providing positive diagnosis of the disease.

Radio-Nuclide Explorations: Ventricular Function Studies

The occurrence of acute myocardial ischaemia is invariably associated with impairment of left ventricular function [39]. Whether or not this is detected depends upon the sensitivity of the technique used to measure this parameter. Continuous monitoring of left ventricular pressure in patients with recurrent spontaneous episodes of myocardial ischaemia has shown elevation of the end-diastolic pressure which precedes the onset of electrocardiographic changes often by several minutes [40]. Furthermore, this rise in left ventricular end-diastolic pressure is associated with a fall in both contraction and relaxation peak rate of change of pressure, reflecting impairment of “contractility” of the ventricle. In other words, the ischaemic ventricle is in “acute failure”, and this ventricular failure is an early manifestation which can be detected by a number of methods. The value of left ventricular pressure recording is obviously severely limited by its invasive nature. However, changes in left ventricular volume and regional contraction probably accompany the pressure changes, and recording these aspects of ventricular function will therefore probably provide useful diagnostic information. Contrast left ventriculography does not provide an adequate solution because of its invasive nature, its interference with cardiovascular physiology and the restriction of total contrast dose. Whilst echocardiography overcomes these problems, geometrical limitations preclude assessment of ventricular volume and impose some restriction on regional wall motion assessment. Many of the above-mentioned limitations can be overcome by radioisotopic methods of assessment of ventricular function.

Angiographic Explorations: Techniques

The name of Mason Sones is inseparably associated with the concept of selective coronary arteriography. Thanks to his work, the examination has become a routine part of cardiological exploration. Sones’ achievement is to have created a veritable doctrine of the selective examination of the coronary arteries. His method is based on the introduction of the catheter probe into the brachial artery by arteriotomy and on the recording of the images by radio-cinematography. The first examinations performed by the pioneers of the method used the direct view of the image intensifler output screen. Beginning in 1958, technical advances proceeded apace. Improvements in the chemical structures of contrast media reduced the rate of ventricular fibrillations. The gradual replacement of cradles by different systems of stands with arms rotating around the patient, the increased resolution power of image intensifies, and the perfecting of axial oblique, sagittal oblique and double-oblique (craniocaudal and caudocranial) projections made detection of stenotic lesions more reliable. The association of coronary arteriography with other procedures (pharmacological tests, exercise tests, atrial stimulation with measurement of the products of cardiac metabolic degradation in the coronary sinus, injection of various radionuclides into the coronary arteries) led to a better understanding of the physiology of myocardial ischaemia. It may be added that examination of the coronary arteries is necessarily accompanied by left ventriculography to explore the muscle side of myocardial ischaemia.

Angiographic Explorations: Normal Results

The left ventricle (LV) can be compared to two partially amalgamated and connected cones representing the filling and ejection chambers (Fig. 1), with a common point towards the front and two adjoining bases towards the spine. The input orifice of the filling chamber and the output orifice of the ejection chamber are connected by the intervalvular trigone, a fibrous formation joining together the mitral septal leaflet and the posterior and left aortic semi-lunar valves (Fig. 2). A cross-sectional view of the LV, perpendicular to its longitudinal axis (Fig. 3), shows a septal wall and three free walls which seem to form a single regularly convex wall successively anterior, lateral and inferior. The practice of left ventriculography in right anterior oblique (RAO) and left anterior oblique (LAO) projections has led to the adoption of a suitable terminology to designate the LV walls: anterior and inferior clearly visible in RAO projection, lateral and septal in LAO projection (Figs. 4 and 5).

Angiographic Explorations: Natural History of Coronary Atheroma and Clinico-Angiographic Correlations

The fact that atheroma impairs the coronary arteries at an early age has been well known since Enos in 1953 reported his autopsy observations in young American men killed in Korea. It is also well known that there is no parallel between the anatomical and clinical severity of the disease, which, in the case of one or more identical arterial stenoses, can be revealed by sudden death, infarction or anginal attack.

Angiographic Explorations: Critical Appraisal of Coronary Arteriography

The degree of reliability of angiographic documents for analysis depends on several factors the film quality of the images (mastery of the techniques of radiological filming and development); knowledge of the enlargement factor (choice of a precise method for its measurement); certainty that no part of the ventricle or coronary arteries escapes observation (correct centring on the film, and panning, if necessary); the possibility of obtaining a complete spatial representation of the left ventricle (LV) (LV filmed in two complementary projections, and simultaneously, if possible — that is, preferably with a biplanar system; certainty that all arterial segments are clear, in at least one projection, of any su- perimposition of an adjacent artery (sufficiently numerous projections and suitable angulations); lack of doubt about the atheromatous or vasospastic nature of a stenotic or occlusive lesion (judicious use of nitroglycerin); the validity of the methods of measurement chosen; and the vigilance, objectivity and competence (level of theoretical knowledge and degree of experience) of the person analysing the ventriculography and coronary arteriography documents.

Radio-Nuclide Explorations: Short-Lived Radio-Nuclides: Present and Future Applications to the Study of Perfusion and Metabolism in the Heart

The clinical methods available can provide useful estimates of ventricular function and detection of myocardial ischaemia in situations where the information may aid the management of the condition. Nevertheless, these widely available methods have a limited ability to quantify and measure the determinants of cardiac physiology that are essential prerequisites to normal ventricular function, and which are disturbed at the onset of myocardial ischaemia (i. e. coronary blood flow and myocardial metabolism).

Radio-Nuclide Explorations: Diagnostic Use of Radioisotopes in Coronary Disease

The clinical applications of nuclear medicine in cardiology have rapidly expanded since the development of imaging cameras and short-lived isotopes suitable for practical use. Indeed, cardiovascular nuclear medicine is often available not only in specialized centres but also in peripheral hospitals. The reasons for this rapid expansion are multiple and reflect the remarkable spread of sophisticated technology in medicine and cardiology. The possibility of investigating pathophysiological problems from a new angle, the appeal of using techniques that have proved useful in research, the attraction of non-invasive methods and the pressure from industry have all played a role in the establishment of the present state of affairs.

Angiographic Explorations: Coronary Arterial Involvement in Various Diseases

The actual frequency of association of a coronary artery disease with a valvular disease is not known with accuracy because published works concern either autopsy analyses after valve replacement [1] or non-randomized arteriographic studies [2], most often limited to aortic valvular diseases [3–6]. Coronary atheromatous lesions have been observed in 15%–40% of aortic [4–7] and 16% of mitral valvular diseases [2]. The association is found to be increasingly more frequent in relation to the subject’s advancing age, a fact which in itself accounts for the difference in frequency between aortic (17.7%), mitro-aortic (21%) and mitral (8.6%) valvular diseases in the autopsy series of Coleman [1].