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Patients with suspected coronary artery disease are sometimes unable to exercise adequately (85% of age calculated maximal heart rate) to validate their ergometric stress test. Some groups suggest performing dipyridamole scintigraphy from the outset but then the information provided by exercise stress testing is lost. The aim of this study was to compare scintigraphies performed after exercise alone and after exercise combined with dipyridamole using a method of quantification. Thirteen patients with ischaemic heart disease without necrosis (coronary lesions greater than 75% luminal narrowing in: 7 right coronary, 10 left anterior descending, 3 left circumflex arteries and 1 left main coronary artery with 50% luminal narrowing) underwent exercise stress testing followed by Thallium imaging. One week later, the same exercise stress test was performed followed by an intravenous injection of dipyridamole and Thallium scintigraphy. The circumference of the radioactivity was traced and the surface of each segment calculated in three different short axis views, subdivided into 4 segments (anterior, lateral, inferior and septal walls). Any segment vascularised by a stenosed coronary artery was considered to be underperfused (105 segments). The ratios of the surfaces of underperfused/normal segments were compared using the two study protocols. Segments of the same wall in the 3 short axis views were grouped in the same myocardial zone. Thirty five myocardial zones were thus obtained: 25 zones were more underperfused after combining exercise and dipyridamole than after simple exercise stress (p = 0.014). The average increase in underperfusion after the combined exercise-dipyridamole was 12.4% compared with 5.5% after exercise alone (p = 0.03). Secondary effects were minimal.(ABSTRACT TRUNCATED AT 250 WORDS)

The human thoracic aorta is usually considered to be a purely elastic vessel. Transoesophageal echo-cardiography (TEE) provides a new approach to study the mechanical properties of the descending aorta. The aim of the study was to evaluate the reproducibility and accuracy of M mode recordings of the human descending thoracic aorta and to appreciate the changes produced by an infusion of glyceryl trinitrate (GTN). The reproducibility of M mode recordings was studied in vitro on plexiglass tubes of different calibre, and also in vivo, the inter and intra-observer error was estimated to 0.6% in vitro and 1% in vivo. The accuracy of the method was evaluated in vitro by comparing the measured values (MV) with the actual diameters of the plexiglass tubes (T): MV = 1.012T + 0.9; r = 0.99; SE = 0.8 mm. The systolic and diastolic diameters of the descending thoracic aorta were measured in 8 healthy volunteers by TEE, before and during continuous intravenous infusion of GTN at a rate of 0.9 mg/hr and then 1.35 mg/hr after a 10 minutes interval. Systolic and diastolic blood pressures were recorded automatically every minute. The results showed a very significant increase in the systolic (from 20.3 +/- 0.7 to 20.9 +/- 1.3 and 22.1 +/- 2.2 mm) and diastolic diameters of the aorta (from 18.3 +/- 0.7 to 19.1 +/- 1.4 and 20.1 +/- 2.4 mm) despite a fall in systolic blood pressure (from 121.3 +/- 7.7 to 114.5 +/- 6.6 and 108.4 +/- 5.4 mmHg). This study shows that TEE is a reliable and reproducible method of measuring the diameter of the human descending thoracic aorta.(ABSTRACT TRUNCATED AT 250 WORDS)

Systolic, diastolic and mean pulmonary artery pressures can be evaluated by Doppler recordings of the maximal velocity of tricuspid regurgitation and early and late diastolic pulmonary regurgitant flow. The aim of this study was to assess the reliability of the calculation of systolic pulmonary artery pressure from pulmonary regurgitant flow by comparing the values with those obtained from the tricuspid regurgitant flow in the same patient. With this objective in mind, we investigated 70 patients with an average age of 45 +/- 34 years, in sinus rhythm, all of whom had tricuspid and pulmonary regurgitant jets which could be recorded with continuous wave Doppler. Systolic pulmonary artery pressure was calculated as follows: from tricuspid regurgitation: maximum pressure gradient + 10 mmHg; from pulmonary regurgitation: 3 x early diastolic gradient - 2 x late diastolic gradient + 10 mmHg. The systolic pulmonary artery pressures calculated from tricuspid and pulmonary regurgitation were: 42 +/- 16 mmHg and 43 +/- 17 mmHg respectively (r = 0.97) with an estimated standard error of 4.7 mmHg. These results show that the recording of pulmonary regurgitation by continuous wave Doppler allows accurate estimation of pulmonary artery pressures. The calculation by the two methods using tricuspid and pulmonary regurgitant jets increases the reliability of the results and provides a means of internal validation of the Doppler technique.

A better selection of patients referred for cardiac transplantation should lead to better surgical results. The presence of severe and irreversible pulmonary hypertension is an important factor and its pretransplantation assessment requires pharmacodynamic testing with vasodilators and dobutamine. The aim of this study of 10 patients in congestive cardiac failure referred for cardiac transplantation was to evaluate enoximone in this indication by comparing it with sodium nitroprussiate (3 micrograms/kg/mn). Intravenous enoximone (total dose of 1.5 mg/kg) increased the cardiac index (+49%; p less than 0.01), slightly reduced the mean systemic blood pressure (-8%; p less than 0.05) whilst inducing a greater reduction in systemic arterial resistances (-36%; p less than 0.01); the fall in mean blood pressure was less than with sodium nitroprussiate (-23%; p less than 0.01). Myocardial oxygen consumption (rate-pressure product) did not increase in contrast to the effect of dobutamine (+21%; p less than 0.01). There was a significant reduction in pulmonary arteriolar resistances (p less than 0.01) with all three drugs but the interpretation of this response and its prognostic significance in patients with a low cardiac output and persistent pulmonary hypertension are discutable even when pulmonary arteriolar resistances are less than 6 Wood units. The value of using an inotropic agent such as Dobutamine or Enoximone is to unmask fixed pulmonary hypertension which may be missed in patients with low cardiac output even with vasodilator drugs, and also to mimic the haemodynamic result of transplantation. In this indication Enoximone may be used like Dobutamine but with the advantage of not increasing myocardial oxygen consumption and being probably less arrhythmogenic.

The acute effects of captopril on haemodynamics, coronary flow and myocardial metabolism were studied in 12 patients with chronic severe cardiac failure (primary cardiomyopathy: 10 cases; ischaemic: 2 cases) in functional Classes III or IV of the NYHA. All patients were male and their average age was 51.3 +/- 14.1 years (range 27 to 68 years). Measurements were carried out under basal conditions and 90 minutes after a single dose of 50 mg (5 cases) or 100 mg (7 cases) of captopril. Captopril administration leads to an increase in cardiac index from 2.05 +/- 0.32 to 2.34 +/- 0.35 l/min/m2 (p less than 0.05) and a greater increase in systolic index from 23.9 +/- 6.7 to 29.8 +/- 6.9 ml/syst/m2 (p less than 0.01), because the heart rate decreased slightly (p less than 0.05). These changes were the result of a decrease in afterload: mean aortic pressure fell from 85 +/- 11.8 to 68 +/- 19.6 mmHg (p less than 0.01) and systemic arterial resistance fell from 2 886 +/- 745 to 2 010 +/- 610 dynes/cm-5/sec/m-2 (p less than 0.01). Captopril also led to a fall in venous tone, i.e. pre-load: left ventricular end diastolic pressure fell from 26.9 +/- 6.1 to 20.8 +/- 6.6 mmHg: p less than 0.01. There was no change in contractility as shown by the absence of variation of the V.max (0.92 +/- 0.18 under basal conditions, and 0.90 +/- 0.15 after 90 minutes).(ABSTRACT TRUNCATED AT 250 WORDS)

The authors report a case of serious streptococcus B endocarditis with a myocardial abscess that recurred after surgery. Streptococcus B endocarditis is a rare disease which is characterized by a pronounced tropism of the organism for cardiac tissues, with severe cardiac valve mutilation and abscess formation in 40% of the cases. A myocardial abscess makes the prognosis worse and must be treated surgically during the acute phase of endocarditis. Modern imaging methods, notably trans-oesophageal two-dimensional echocardiography and computerized tomography should now be used to detect such abscesses.

We present the case of a 50-year old man who progressively developed tricuspid valve insufficiency with opening of a patent foramen ovale responsible for right-to-left shunt with polycythaemia. The tricuspid valve insufficiency was due to a foreign body, probably of surgical origin as suggested by its radiological image and by the patient's previous history. It would have been introduced, far away from the tricuspid valve (compound fracture of the wrist), several years previously. At surgery, we found the foreign body embedded in the valve system. As a possible mechanism for the mutilation, an undiagnosed endocarditis was suspected but could not be confirmed. Three cases tricuspid endocarditis (with foreign bodies in the right ventricle) and 3 cases of asymptomatic tricuspid valve foreign bodies have been published. Fifty-five cases of foreign bodies introduced peripherally and migrated into the heart, the pericardium and the pulmonary artery are reviewed.

Twenty two cases of recurrent perivalvular leaks in aortic valve prostheses were reviewed in a multicentre cooperative study. From 1963 to 1978, 22 patients, mean age 39 years, underwent aortic valve replacement; 18 patients had aortic regurgitation, 6 due to infective endocarditis, and 4 patients had calcific aortic stenosis. Eight Starr-Edwards, 6 Smeloff-Cutter, 2 Braunwald-Cutter, 3 Björk, 1 Lillehei-Kaster and 2 bioprostheses were inserted. All 22 patients had to be reoperated for perivalvular leaks due to active or previous infective endocarditis in 7 cases. The prostheses implanted (3 reinsertions, 19 valve replacements) were 10 Starr-Edwards, 4 Smeloff-Cutter, 5 Björk, 1 Lillehei-Kaster, 1 Magovern and 1 bioprosthesis. All 22 patients had further perivalvular leaks, 6 caused by infective endocarditis, and 15 patients underwent a third operation. The prostheses implanted this time (2 reinsertions, 13 valve replacements) were 4 Starr-Edwards, 3 Smeloff-Cutter, 7 Björk and 1 bioprosthesis. Four patients had a third perivalvular leak, and 2 patients a fourth perivalvular leak. The first and second episodes of perivalvular leak were detected early in over half the cases. They were associated with cardiac failure, angina and hemolysis in 20 to 45% of cases. The average period between the first and second operations, and the 2nd and 3rd operations were 15 months and 9 months respectively. Overall, 11 patients died (50%), 4 due to cardiac failure and 3 of sudden death; 3 patients have been lost to follow-up (14%), and there are 8 survivors (36%) with a mean follow-up period of 5 years. However, the mortality rate when the cause of perivalvular leak was infective, was 82%, and only 18% when the cause was mechanical. The factors which favour recurrent perivalvular leaks are infection (30% of cases) and technical difficulties related to the poor quality of the aortic ring (calcification, dystrophy or dilatation). The prevention of this complication depends on careful peroperative technique, the use of certain surgical bypass techniques, a constant battle against infection, and regular examination of operated patients.

Transoesophageal pacing is mainly used for treatment of supraventricular tachycardias and assessment of refractory periods of accessory pathways. It has been proposed for the study of sinus node function and A-V nodal conduction. The aim of this study was to know if transoesophageal pacing could modify the vago-sympathetic tone, therefore the results of the tests, knowing it can be discomfortable and that endodigestive procedures can induce vagal responses. Furthermore, the stimulation is elicited near the left atrium, and not in the right atrium as during endocavitary tests. We have compared in 20 patients (age 68 +/- 12) the results obtained by both endocavitary and transoesophageal pacing (tension 21.2 +/- 4.5 V, duration 16 msec, interelectrode spacing 30 mm). We measured sino-atrial conduction time (SACT), sinus node recovery time (SNRT), Wenckebach's point and nodal refractory periods. After introduction of the oesophageal lead we observed a significant (p less than 0.01) but slight and transitory tachycardia. The results of A-V nodal conduction parameters were not significantly different and were significantly correlated (r = 0.94 for Wenckebach's point and effective refractory period). For the sinus node function, there was no significant difference between the parameters if the oesophago-atrial delay (mean 104.4 +/- 25.9 msec) is taken into account. The correlation is poor for sino-atrial conduction time (corrected SACT, r = 0.55), tighter for sinus node recovery time (maximal corrected SNRT, r = 0.92).(ABSTRACT TRUNCATED AT 250 WORDS)

This prospective study was undertaken to assess the results of 2D echocardiography in the assessment of valvular and subvalvular lesions in mitral stenosis. The echocardiographic findings (E) were compared with peroperative and laboratory anatomical examination of the excised valve (A). The following criteria were compared: 1) planimetry of mitral valve surface area, 2) mobility of the anterior leaflet, assessed anatomically by the flexibility of the tissue, and echocardiographically by the amplitude of early diastolic excursion, 3) length of anterior and posterior leaflets, 4) presence of calcification, 5) length of the longest tendinae chordae, measured from the papillary muscle to the insertion of the valve, 6) thickness of the thickest tendinae chordae attached to each leaflet. Echocardiography was carried out preoperatively by two different operators without knowledge of the haemodynamic and later anatomical findings. The anatomical results were taken as reference. Mitral valve surface area measured by both methods was comparable (A = 0,96 +/- 0,28 cm2; E = 1,04 +/- 0,33 cm2, N = 17, t = NS) and a good correlation was found between the two measurements (r = 0,79; p less than 0,01). 2D echo assessed the loss of valvular mobility by limitation of early diastolic opening of the AML with a sensitivity of 71 p. 100 and a specificity of 70 p. 100. Measurement of valve length of the anterior (N = 14) and posterior leaflets (N = 15) may be difficult in the presence of severe calcification. The results of both measurements were comparable. AML, 25,2 +/- 1,9 mm (A) and 24,6 +/- 2,1 mm (E); PML, 13,9 +/- 1,9 mm (A) and 14,2 +/- 2,2 (E) correlated well, r = 0,71 and r = 0,71 respectively (p less than 0,01).(ABSTRACT TRUNCATED AT 400 WORDS)

A study has been made of the haemodynamic affects of a single intravenous injection of amiodarone chorhydrate (5 mg/kg); the injection was given at rest to six normal subjects and six patients with coronary insufficiency due to atherosclerosis. The effects of the drug are most marked at the fifteenth minute after injection, and are: slowing of the heart rate; lessened cardiac output and left ventricular effort; a significant increase in mean pulmonary arterial pressure and diastolic pressure; slight variations in flow in the coronary sinus, with an increase in the ratio of coronary sinus flow to cardiac output. Amiodarone chlorhydrate appears to exert a favourable action upon the heart because, while it maintains myocardial perfusion, it tends to diminish the myocardial oxygen requirement by decreasing the rate of contraction and the contractility of the myocardium.

The haemodynamic and myocardial metabolic effects of intravenous Labetalol were studied in 7 normotensive coronary patients with at least one significant stenosis on the left anterior descending artery. The study consisted of 5 successive observation periods: basal (I); during atrial pacing at the theoretical maximal heart rate or when anginal pain occurred (II); return to basal conditions (III); 20 minutes after an injection of 1.5 mg/kg of Labetalol over 3 minutes into the pulmonary artery (IV); during repeat atrial pacing at the rate achieved during phase II (V). There was no significant difference between phases I and III except for a slightly faster heart rate in phase III. The effects of Labetalol were assessed by comparing the results during phases III and IV between phases II and V and by analysing the variations between phases I, II, IV and V. In comparison with basal conditions (phase III), Labetalol (phase IV) induced a slight decrease in cardiac output (p less than 0.05), a decrease in aortic pressure and systemic arterial resistances (p less than 0.01) and of the double product. Coronary sinus flow did not change but myocardial oxygen consumption fell by an average of 11% (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

The authors report the case of an asymptomatic 45 year old man in whom an abnormal origin of the left coronary artery was discovered fortuitously. Coronary angiography was carried out for electrocardiographic signs of anterior myocardial infarction and showed the left coronary artery arising from the pulmonary artery: there was apical dyskinesia with alteration of global left ventricular function. The ostium of the left coronary artery was closed and a saphenous vein aorto-left anterior descending artery bypass was performed. There were no complications. Left ventricular function has not improved 8 months after surgery. The haemodynamic and coronary signs of myocardial ischaemia demonstrated preoperatively regressed after surgery: the coronary "steal" caused by the malformation which led to poor perfusion of the territory of the left coronary artery has therefore been corrected by surgery. This procedure should be carried out as early as possible in order to limit extension of the myocardial lesions.

Several authors have studied variations in myocardial thickness on short-axis sections cut through healthy postmortem hearts. The circumferential profiles showed a series of minima and maxima, with a minimum at the septum, a maximum at the anterior interventricular junction and another at the anterolateral papillary muscle, a minimum at the inferior wall followed by a maximum at the posterior papillary muscle, then at the posterior interventricular junction, after which came a septal minimum again. When examined by short-axis thallium 201 tomography, the left ventricle does not look like a ring of even density. The purpose of this study was to try and explain the changes in density observed by variations in thickness and to devise a quantification method that would take anatomical features into account. 23 patients with normal coronary angiography underwent thallium 201 scanning after exercise. Circumferential profiles were drawn from short-axis sections with the angle on the abscissa and the number of sections on the ordinate. 29 other patients with a more than 75 p. 100 stenosis of coronary vessels (anterior interventricular artery 15, right coronary artery 10, circumflex artery 8, diagonal artery 4) had the same examination. The circumferential profiles of normal subjects closely resembled those of anatomical sections, with a minimum at the upper and anterior septal wall (the limit between the two areas being undefinable), a maximum at the anterolateral papillary muscle and adjacent myocardium, a minimum at the inferior wall and a maximum at the posterior papillary muscle and adjacent septum. These curves enabled us to determine the relative perfusion values of one area compared with another, which will serve as reference.(ABSTRACT TRUNCATED AT 250 WORDS)

The accuracy of continuous 24 hour recordings (Holter's method) in the diagnosis of coronary insufficiency has been studied in 115 patients, by comparison with coronary arteriography. The technique was highly specific, but only fairly sensitive under the conditions of the study, because of the relative inactivity of the patients or the absence symptoms during the recording. It has allowed us to detect certain painfree or relatively painless forms of myocardial ischaemia which may be severe, and to have a clearer understanding of the effect of treatment. Comparison with the exercise electrocardiogram has shown inconsistencies due to the limitations of the two techniques. Holter's method is a particularly simple way of detecting coronary insufficiency, and is most useful when exercise tests are impossible or contraindicated.

Transesophageal echocardiography is a new method of cardiac imaging with well-defined indications. In view of the absence of hindering anatomical obstacle between the probe and cardiac structures, the images obtained are of high definition, especially as regards the atria and atrial appendages, the mitral, aortic and tricuspid valves and the thoracic aorta. Being easy to perform and little traumatic, this method can be used in ambulatory patients. It is also valuable in intensive care patients and in the peri-operative period. Transesophageal echocardiography is primarily indicated to explore cardiac valve prostheses, notably those of the mitral valve, to identify vegetations and abscesses in infective endocarditis, to detect intra-atrial tumours and thrombi, to evaluate dissections of the aorta, to study the mechanism of mitral regurgitation, to investigate some congenital cardiopathies in adults, such as interatrial septal defects, and to monitor left ventricular function before and after surgery. Owing to its major contribution to the diagnosis of these potentially dangerous diseases, it should soon become a very useful and even indispensable complement of transthoracic exploration in certain cases.

The long term fate of mitral valve replacements (over 2 years) has been studied by the collection of information from many French cardiology centres. The Starr valve with a plastic ball-valve is by far the most commonly used prosthesis. The late complications are dominated by thrombo-embolic sequelae. The functional result seems to be proportionally better the earlier the stage at which the operation is carried out.