Electronic article surveillance: a possible danger for pacemaker patients.

In order to evaluate if antitheft devices commonly designed as electronic article surveillance (EAS) systems can be dangerous for pacemaker patients, in vitro and in vivo studies were made in close cooperation between a pacemaker center and an EAS designer. Three types of EAS radiation including radiofrequency, magnetic, and pulsed electromagnetic fields were applied to various pacemakers. The in vitro study consisted of exposing to the EAS fields 28 pacemakers connected to unipolar leads. Radiofrequency fields and pulsed electromagnetic fields evoked minor effects and no prolonged inhibitions. When exposed to magnetic fields, most of the pacemakers switched to "fixed rate" pacing, but inhibitions were observed in 13 pacemakers exposed to 300 Hz, and in 14 pacemakers exposed to a 10-kHz magnetic field when they were moved at cardiac frequencies within the fields. The in vivo study was made on 32 volunteers treated by 26 different pacemakers: 22 single chamber and ten dual chamber. All patients had been monitored in the pacemaker clinic and pacemakers were working well. Radiofrequency and pulsed electromagnetic fields did not affect the pacemaker function. Magnetic interference evoked prolonged inhibition of seven out of the ten dual chamber pacemakers, causing brief asystole in patients being continually paced. None of the dual chamber pacemakers incorporated "safety stimulation intervals" after ventricular blanking. The EAS artifact was sensed after the ventricular blanking causing a cross-talk ECG pattern. No reprogramming was induced by the electromagnetic fields. This experience demonstrates that certain EAS may be dangerous for pacemaker patients. Following this cooperative study a pacemaker safe EAS circuit delivering short bursts of magnetic fields has been designed.

[Contribution of color echocardiography to the diagnosis of post-traumatic left ventricular-right atrial septal defect]. / Apport de l'échocardiographie couleur au diagnostic de communication ventricule gauche-oreillette droite post-traumatique.

The authors report the case of an acquired left ventricle--right atrial communication after closed chest trauma. This communication was associated with rupture of the aortic isthmus and complete atrioventricular block. The left-to-right shunt which was assumed for a long time to be a small, well-tolerated, ventricular septal defect, finally required surgical repair. The diagnosis was eventually made clear by Doppler color flow mapping which was of great value in orienting the surgical procedure.

[Prognostic value of two-dimensional echocardiography before aneurysmectomy in anterior aneurysm of the left ventricle]. / Evaluation du rôle pronostique de l'échocardiographie bidimensionnelle avant anévrismectomie pour anévrisme antérieur du ventricule gauche.

The prognostic value of echocardiographic apical 4 chamber recordings was assessed retrospectively in 18 patients who underwent left ventricular aneurysmectomy following anterior wall myocardial infarction. After an average follow-up period of 2 years, 7 patients had died or remained in functional Classes III or IV (Group 1) and 11 patients had satisfactory clinical outcomes (Group 2). There were no significant clinical or coronary angiographic differences between the two groups. The left ventricular surface area, transverse diameter and fractional shortening of the surface were also comparable in the two groups. The surface area of the aneurysm was greater in patients in Group 1 (37.4 +/- 11.8 cm2 vs 21.1 +/- 15.8 cm2, p less than 0.05). However, the more discriminating parameters were those related to the non-aneurysmal contractile zones (NACZ). Patients in Group 1 had a smaller relative surface area of the NACZ than those in group 2; 6 of the 7 patients in Group 1 had NACZ of less than 40 per cent of the left ventricle compared with none of the patients in Group 2 (p less than 0.001). In addition, the function of the NACZ was significantly worse in Group 1: surface fractional shortening: 9.6 +/- 10.2% vs 32.6 +/- 8.3% (p less than 0.001); ejection fraction: 20.7 +/- 9.1% vs 41.6 +/- 6.1% (p less than 0.001). All patients in Group 1 and none in Group 2 had ejection fractions of the NACZ of less than 30 per cent. Therefore, the apical 4 chamber view provides valuable prognostic information in patients who are candidates for surgical resection of left ventricular anterior wall aneurysms.

[Retrocardiac pheochromocytoma associated with a double carotid site. Diagnostic and therapeutic discussion]. / Phéochromocytome rétrocardiaque associé à une double localisation carotidienne. Discussion diagnostique et thérapeutique.

A case of cardiac paraganglioma is reported in a 30 year old man operated two years previously for bilateral carotid body paraganglioma. Due to the persistence of high catecholamine levels in the superior vena cava, a cardiac localization, suspected on echocardiography, was confirmed by coronary angiography. MRI identified the exact site of the tumour in contact with the posterior surface of the left atrium and the great vessels of the base of the heart. Complete resection was performed via sternotomy. The adhesions to the great vessels and atrium and the retrocardiac site of the tumour required continuation of the operation under CPB with transection of the superior vena cava, aorta and pulmonary artery in order to achieve complete resection despite the hypervascular nature of the tumour. Postoperative collapse of peripheral resistance requiring 48 hours of adrenaline infusion demonstrated the immediate efficacy of the surgical operation. After a follow-up of four months, the blood pressure and catecholamine levels remained normal. The authors emphasise: the value of MRI for the topographic diagnosis of thoracic lesions, the association of a double carotid body paraganglioma and a mediastinal tumour, especially cardiac, which has already been reported in the literature and the availability of CPB in order to perform complete resection of these tumours with complete security in view of their intimate relations with cardiac cavities and the vessels of the base of the heart.

[Infective endocarditis of a valve prosthesis. Multicenter study (179 cases)]. / Endocardite infectieuse sur prothèse valvulaire. Etude multicentrique (179 cas).

Over a 5-year period (1982-1986) 176 cases of infective endocarditis on prosthesis (IEP) were recorded in 40 cardiology departments. 65 p. 100 of the patients were male, and the mean age of the population was 51 years. Mechanical prostheses were involved in 57 p. 100 of the cases and bioprosthesis in 43 p. 100. There was a high proportion of initial indications for bacterial endocarditis (18 p. 100) and for reoperation on prosthesis (10 p. 100). IEP developed early in 40 cases and late in 139 cases; 19 (48 p. 100) of the early IEPs were staphylococcal, while 31 p. 100 of late IEPs were streptococcal (p less than 0.01). 143 patients were reoperated upon within less than 1 month in 41 p. 100 of the cases, with a pre-operative antibiotic therapy of less than 10 days in 39 p. 100. Reoperation was performed in stage IV or as an emergency in 45 p. 100 of the cases. Abscesses were three times more frequent with aortic prostheses than with mitral prostheses (58 p. 100 vs 20 p. 100, p less than 0.001). Vegetations were more frequent on mechanical prostheses than on bioprostheses (43 p. 100 vs 31 p. 100, NS). The operative mortality rate was 25 p. 100; the mortality rate of unoperated patients was even higher (31 p. 100). The survival rate in operated IEP was 51 p. 100 at 30 months, as against 46 p. 100 at 12 months in unoperated IEP.(ABSTRACT TRUNCATED AT 250 WORDS)

[Cardiac stimulation in children. 20 years' experience]. / La stimulation cardiaque infantile. Expérience de vingt ans.

Between July, 1967 and December, 1987, 71 children and adolescents (43 boys, 28 girls) aged from 9 days to 20 years (mean 7.8 years) underwent pacemaker implantation. In 91 p. 100 of the cases this treatment was performed for complete atrioventricular block (CAVB). Surgical CAVB was the reason for 59 p. 100 of implantations (correction of tetralogy of Fallot and, more recently, of complex cardiopathies), the second main reason (16.9 p. 100) being nonsurgical CAVB associated with heart disease; the children in this group were young (mean age 4.2 years), and the prognosis mainly depended on the heart disease. Isolated congenital CAVB accounted for only 8.5 p. 100 of pacemaker implantations; these were older children (mean age 13.7 years), and the decision to implant was often difficult to reach in the absence of major functional disorders; following implantation, it was frequently found that isolated congenital CAVBs regarded as being well tolerated in fact were unrecognized handicaps. Acquired CAVB (7 p. 100) mostly consisted of Kearns' syndrome (4/5 cases). In addition, 3 children with sinus node disease and 1 with Romano-Ward syndrome benefited from cardiac pacing. Seven children died; death was in no case due to pacing but to the heart disease associated with CAVB. Endocardial pacing (68.2 p. 100 of primary implantations during the last decade) was preferred to epicardial pacing. Since 1985 we have been using exclusively screwed endocardial monopolar electrodes. The pacemakers were usually of the single-chamber ventricular type (85.9 p. 100 of primary implantations), but since 1987 dual-chamber pacemakers have been increasingly preferred for children with permanent CAVB or for replacement of pacemaker cases. Single-chamber noncompetitive ("demand") pacemakers were implanted in only 2 children: one pacemaker was connected to a ventricular electrode (atrial paralysis), the other to an atrial electrode. Whatever the type of electrode used, the pacemakers were implanted in the abdominal region in very young infants and in the pectoral region in children older than 3 or 4 years. Breakage of the wire was the main complication. Rises in threshold are the major drawback of epicardial pacing, as they require reoperation when the energy delivered cannot be effectively programmed. Endocardial pacing, preferably with a dual-chamber instrument, seems to be the best method, being the least aggressive, with minimal complications in short and very long term; it is justified as first-line treatment of permanent or predominant CAVB.(ABSTRACT TRUNCATED AT 400 WORDS)

[10-year results of anastomoses of the left internal mammary artery to the anterior interventricular artery. Angiographic and radionuclide controls]. / Résultats á dix ans des anastomoses de l'artére mammaire interne gauche á l'artére interventriculaire antérieure. Contrôle angiographique et isotopique.

The long term patency of left internal mammary artery graft is better than that of saphenous vein graft. The aim of this study was to determined if this high patency rate was accompanied by a satisfactory myocardial perfusion. Among 143 patients treated with an internal mammary artery graft on the left anterior descending artery between 1972 and 1976, 42 patients underwent coronary angiogram and exercise tomoscintigraphy (thallium 201) over 10 years after surgery. The left internal mammary artery was patent in 92% without any atheromatous lesions. The myocardial perfusion in the area supplied by the left anterior descending artery was normal in 74%. A slight ischemia appeared during exercise in 19% without any clinical symptoms. This long term study shows excellent anatomical results correlated with a good myocardial perfusion during exercise in most cases.

Endarterectomy of the left main coronary artery stenosis by a 'transpulmonary artery approach'.

For better visualization of the left main coronary artery, a new technique involving transection of the main pulmonary artery is described. With this new method it was possible to perform endarterectomy of the left main coronary artery in 35 patients from February 1981 to July 1987. The endarterectomy incision was closed with a pericardial or venous patch. We had no mortality, and 91% are free from angina at a mean follow-up of 31 months. Angiographic evaluation was performed in 19 patients revealing good patency of the left main artery. This procedure is safe, and we recommend it in isolated left main coronary artery stenosis without distal involvement and with good left ventricular function.

Two-dimensional echocardiographic assessment of the right ventricle in patients with chronic obstructive lung disease.

A consecutive series of 40 patients (39 men, one woman; mean age 54.1 +/- 8.2 years) with chronic obstructive lung disease (COLD) underwent right heart catheterization and 2-D echocardiographic examination within 72 hr. An adequate 2-D echocardiographic study was obtained in 32 patients (80 percent) using the apical and/or subcostal views. Mean pulmonary artery pressure at rest and during exercise were correlated with right ventricular diameters and areas in end-systole and end-diastole (r = 0.63 to 0.73). Correlations between right ventricular free wall thickness and pulmonary artery pressure were weak (r = 0.51 and 0.57). Right ventricular end-diastolic pressure was also weakly correlated with right ventricular dimensions (r = 0.45 to 0.51), whereas right ventricular area fractional shortening was not correlated with hemodynamic parameters. Patients with previous episode of right heart failure had larger right ventricles than those without such episodes. Thus, 2-D echocardiography appears useful to study the right heart chambers in patients with COLD.

Echocardiographic features of right atrial thrombi.

The clinical and echocardiographic features of six patients in whom a right atrial thrombus was detected using two-dimensional echocardiography are reported. In four patients with acute cor pulmonale, the thrombus appeared as a coiled mass moving freely within the right atrium and prolapsing through the tricuspid valve. In another patient referred for syncope, a large coiled mass attached to the lateral wall of the right atrium was seen prolapsing regularly through the tricuspid valve, simulating an atrial myxoma. In the remaining patient who presented with chronic cor pulmonale, two-dimensional echocardiography demonstrated a motionless ovoid mass with a broad base of attachment to the interatrial septum.

[Clinical, echocardiographic and evolutive aspects of right atrial thrombosis]. / Aspects cliniques, échocardiographiques et évolutifs des thromboses de l'oreillette droite.

The clinical and echocardiographic features of right atrial thrombi were examined in 9 patients, 5 men and 4 women aged 16 to 86 years. The 2D echocardiographic diagnosis was confirmed at autopsy (4 cases) or by the association of severe recurrent pulmonary embolism (5 cases). Three patients had associated ischaemic heart disease and on patient had dilated cardiomyopathy. The clinical presentation was: acute cor pulmonale (5 cases including 2 patients which biventricular myocardial infarction), chronic post-embolic cor pulmonale (1 case), tricuspid valve obstruction (1 case), general ill health with pyrexia (1 case) and heparin-induced thrombocytopenia (1 case). Predisposing factors included: absence of anticoagulent therapy (7 cases), previous supraventricular arrhythmias (2 cases) and right ventricular failure (6 cases, including 2 of right ventricular infarction). In 2 patients the thrombi were relatively immobile and had a wide base of implantation on the interatrial septum; in 1 patient, multiple thrombi were observed lining the right heart cavities from the inferior vena cava to the pulmonary infundibulum. In the other 6 patients, the thrombi were very mobile with a visible pedicule of implantation (2 cases) or totally free (4 cases). The variable polylobulated appearances, completely irregular whirling motion and intermittent prolapse into the tricuspid valve were characteristic features of the latter 4 cases. They disappeared spontaneously (2 cases) or after fibrinolytic therapy (2 cases) in under 36 hours. Three patients were operated with one postoperative death. The global hospital mortality was 22%. The present occasional detection of right atrial thrombosis will certainly become more common if patients with pulmonary embolism, right ventricular infarction or deep venous thrombosis are systematically examined by 2D echocardiography in the acute phase of their illness.

[Apical hypertrophic cardiomyopathy: an element in the continuum of hypertrophic cardiomyopathies]. / La cardiomyopathie hypertrophique apicale: un élément du continuum des cardiomyopathies hypertrophiques.

Fourteen cases of apical hypertrophic cardiomyopathy (i.e. hypertrophy localized to the distal half of the left ventricular wall) are reported. There were 12 men and 2 women aged from 21 to 84 years. Only one of the patients presented, at first consultation, with severe functional symptoms, namely stage IV dyspnoea. ECG tracings were always abnormal, but the classical giant T waves were found in only 7 patients. In the 9 patients who had cardiac catheterization the left ventricular end-diastolic pressure was raised, and angiography showed an "ace of spades" diastolic image of the left ventricle with systolic obliteration of its tip. The distribution of parietal hypertrophy was best studied by two-dimensional echocardiography: the left ventricular apex was affected alone in 7 patients and concomitantly with the adjacent segments of the left or right ventricle in the other 7 patients. A family study showed that 3 patients had a descendant with obstructive cardiomyopathy. At a 4.6 years' follow-up the course of the disease was usually favourable. Apical hypertrophic cardiomyopathy is not a particular entity but one of different possible forms of hypertrophic cardiomyopathy. It seems to be benign in most cases.

[Compressive pericardial effusion after heart surgery in the adult. Contribution of bidimensional echocardiographic findings]. / Epanchement péricardique compressif après chirurgie cardiaque de l'adulte. Apports de l'échocardiographie bidimensionnelle.

In series of 1450 consecutive cardiopulmonary bypasses for cardiac surgery in adults, we observed 20 cases of post-operative compressive pericardial effusion. The effusion occurred some time after the thoracic drains were removed and had to be evacuated. Two-dimensional echocardiography proved essential to the diagnosis : it easily detected the lesion even when clinical symptoms were misleading but above all, it demonstrated, in our series, that the classical post-operative "tamponade" is a specific entity consecutive to posterior, circumscribed, small volume effusions which mainly compress the left cardiac cavities.

[Value of isotopic methods in the diagnosis of myocardial infarction of the right ventricle]. / Intérêt des méthodes isotopiques dans le diagnostic des infarctus du myocarde du ventricule droit.

In the left ventricle, isotope techniques can be used to study the perfusion of the myocardium or the ventricular function. Because of the thinness of the walls of the right heart, the classical examinations and Thallium 201 perfusion cannot be used to demonstrate a disorder of perfusion in the right ventricle. Nevertheless, it is possible, with the aid of Technetium 99m labeled pyrophosphate, to diagnose and localise necrosis of the inferior wall with an acceptable degree of sensitivity, during the acute phase of the infarction. However, the major value of isotope techniques is to evaluate right ventricular function by determining the value of the global ejection fraction and the kinetic anomalies of the different walls. These methods, together with echocardiography, allow the diagnosis of lesions of the inferior part of the right ventricle in patients with inferior necrosis... Furthermore, because these methods allow quantification and because they are reproducible and repeatable, they can be used to follow the course of the right ventricular function in response to treatment.

[Infarction of the right ventricle. Contribution of two-dimensional echocardiography]. / Infarctus du ventricule droit. Apport de l'échocardiographie bidimensionnelle.

This study, based on 39 cases, confirms the value of two-dimensional echocardiography in the diagnosis of right ventricular infarction during the acute phase. This diagnosis is confirmed by the presence of abnormalities of the segmental kinetics always present in the inferior wall and less frequently in the anterior wall. The inferior part of the septum is affected in two thirds of cases. Right ventricular dilation is frequently observed, but is not constant. Two-dimensional echocardiography has a diagnostic sensitivity similar to that of isotope ventriculography, but greater than that of haemodynamic investigations. Finally, apart from the easy demonstration of complications (tricuspid incompetence, septal rupture, intracardiac thrombosis), two dimensional echocardiography can be used to evaluate right ventricular function.

[Apical hypertrophic myocardiopathy. Apropos of 10 cases]. / Myocardiopathie hypertrophique apicale. A propos de 10 observations.

Apical hypertrophic cardiomyopathy is a recently defined subgroup of primary hypertrophic cardiomyopathy. Ten new cases are studied. The electrical features (anomalies of repolarisation) were constant and giant negative T waves were observed in 3 out of 10 cases. Two-dimensional ultrasonography confirmed the diagnosis in every case; the optimal views consisted of 4 cavity scans obtained by the apical approach. When angiography was performed (7 cases out of 10), it confirmed the ultrasonographic findings and was able to eliminate any coronary artery lesions. The patients had a mean age of 48.3 years with a marked male predominance (sex ratio of 0.8) and all of the patients are alive with a mean follow-up of 3.4 years. The functional handicap was moderate (class III: 1 case, class II: 5 cases and class I: 4 cases) and did not progress during the period of follow-up. The family surveys performed revealed that apical hypertrophy can be integrated into the spectrum of segmental hypertrophic cardiomyopathy. In two cases, this survey revealed the coexistence in the same family of segmental hypertrophy with different topography. The long term prognosis of this disease is unknown and the authors consider that the risk of ventricular arrhythmia justifies routine rhythmological evaluation in order to guide subsequent treatment.

[Sudden death in patients wearing pacemakers]. / La mort subite chez le porteur de stimulateur cardiaque.

10 to 30 p. cent of patients with cardiac pacemakers die suddenly. In most cases, the cause of death can not be established. Racing of the pacemaker is a rare but definite cause of sudden death. In contrast, failure of the stimulation, which occurs much more frequently, and which is due to failure of the pacemaker or the wire or to an elevation of the threshold of stimulation, rarely causes sudden death because of the development of an idioventricular rhythm, leading to detection of the fault. Competitive rhythms do not appear to be more dangerous than accidental inhibition in sentinel pacemakers; both of these mechanisms can lead to ventricular tachycardia which may degenerate to ventricular fibrillation. Programmable pacemakers have certain advantages and disadvantages, in that the programming may prove to be inappropriate. In most cases, the ventricular fibrillation is spontaneous, occurring in the context of myocardial failure. The extension of the indications for pacemakers is certainly responsible for the relatively high incidence of sudden death.