Contribution of a pacemaker bradycardia detection algorithm in the study of patients with carotid sinus syndrome.

While carotid sinus syndrome (CSS) is often suspected as a cause of syncope in the elderly, whether it represents an indication for cardiac pacing may remain uncertain. Bradycardia algorithms included in pacemakers are now able to establish a precise relationship between spontaneous asystole and occurrence of symptoms and strengthen the indication for permanent pacing. This study included seven men and three women (70.5 +/- 7.3 years of age) who, over an average period of 54.1 +/- 17 months, had suffered from syncope (12.6 episodes/patient) and presyncope (11.2 episodes/patient) attributed to pure cardioinhibition (2 patients) or mixed CSS (8 patients). Other sources of symptoms were excluded by thorough clinical evaluations, including Holter monitoring, echocardiography, and electrophysiological testing. All patients received a CHORUS 6234 pacemaker, the memory of which includes a dedicated bradycardia detection algorithm capable of storing atrial and ventricular chains, and date and time of the last ten pauses and/or bradycardic events. After a initial period of 14.7 +/- 8 months, during which symptoms were suppressed, the bradycardia algorithm was activated. From then on, a cumulative increase in the number of patients presenting with diurnal pauses was measured (1 month, n = 0; 3 months, n = 6; 9 months, n = 7; 2 years, n = 8). Fourteen episodes of diurnal asystole were recorded. The mean duration of the longest episodes of spontaneous ventricular standstill was 6,319 +/- 1,615 ms and was due to sinoatrial block (n = 7), atrioventricular block (n = 5), and a combination of both (n = 2). In conclusion, activation of the CHORUS bradycardia algorithm allowed confirmation of the appropriateness of permanent pacing in a majority of patients suffering from CSS.

Reliability of single-lead VDD atrial sensing and pacing during exercise.

If atrial sensing ability of a single-lead VDD pacemaker is well accepted at rest, the detection quality by atrial floating electrodes remains less recognized during exercise. The aim of this study was to verify, during treadmill test and a continous telemetry, the atrial tracking performance using four different leads technologies. From November 1994 to July 1997, 21 patients (71.3 +/- 6.3 years old, 7 female, cardiopathy: 57%) were paced for isolated high degree (permanent: 13, paroxystic: 8) AV block. The implanted devices were the Vitatron Saphir/Brillant lead (13 patients), Intermedics Unity/425/04-13 lead (5 patients), Pacesetter Addvent (2 patients), and Biotronik Eikos (1 patient). The acute atrial signal amplitude was 1.66 +/- 0.75 mV. The treadmill test used the chronotropic assessment exercise protocol after pacemaker reprogramming to detect atrial undersensing (AV delay < or = 120 ms, no hysteresis, no flywheel, upper rate increase). The mean delay was 31.1 weeks (range 1-100). The testing duration was 6.1 +/- 2.3 minutes, the number of steps was 3.3 +/- 1.3 per patient, and the peak exercise rate was 135 +/- 19 beats/min. At rest, complete atrial tracking was complete in 90% of the patients, and during testing in only 23.8% of the patients, while AV synchronization > 95% was present in 57.1%, > 90% in 71.4%, and > 85% in 90.4% of patients (Vitatron 13/13, Intermedics 3/5, Biotronik 1/1, and Pacesetter 1/2). During the recovery period synchronization was always > 95%. The mean P wave amplitude at rest was 1.1 +/- 0.5 mV; during the first step, 1.04 +/- 0.61 mV; second step, 0.94 +/- 0.53 mV; third step, 0.82 +/- 0.58 mV; fourth step, 0.67 +/- 0.39 mV; and during recovery, 1.13 +/- 0.67 mV. The mean P wave decrease signal at peak of exercise is 0.21 mV (from -1.31 to +0.5). In fact, P wave variations have several patterns: a decrease was measured in 7 patients, an increase in 2 patients, and no significant change in 7 patients. Single-lead VDD P wave identification during exercise was almost accurate. However, often there was progressive lowering of atrial sensing with transient loss of AV synchrony.

Wavelength and atrial vulnerability: an endocavitary approach in humans.

If atrial vulnerability parameters are well defined, wavelength (WL) measurement (conduction velocity x refractory period), has never been assessed through an endocavitary electrophysiological exam. We investigated 30 patients (14 female, mean age 63.4 +/- 13 y.o.), 10 with paroxysmal atrial fibrillation (PAF group), 10 with ischemic cerebral injury (ICI group) by comparison with 10 controls (C group). The upper to lower right atrium conduction time and velocity were measured in the right atrium with a decapolar electrode catheter applied along the free wall. Others parameters correlated to atrial excitability were also taken into account: effective (ERP) and functional refractory periods (FRP); spontaneous or paced atrial electrogram (A1) or extrastimulated atrial electrogram (A2) widths, ERP/A2 ratio, provocative atrial testing. Measurements were taken in sinus rhythm and in 600-460 ms paced cycle lengths. If ERP, FRP, A1 widths are the same in the 3 groups, PAF and ICI groups have a significant increased conduction time and lower conduction velocity, leading to a shorter A1 WL during 600 and 460 ms paced rhythms (p < 0.05) and A2 WL during 460 ms paced rhythm. The provocative testing was positive in 60% of PAF and ICI groups, and there is a significant correlation between arrhythmia induction and 600 ms A1 WL or 460 ms A2 WL. This electrophysiological study suggests the possibility of an approach in humans of wavelength concept and proves the presence of correlation between a short wavelength and atrial spontaneous or induced arrhythmias. A no-arrhythmia band (A1 WL > 17 cm during 600 ms paced rhythm, A1 WL > 16 cm or A2 WL > 12 cm during 460 ms paced rhythm) and a fibrillation-band (A1 WL < 12 cm during 600 and 460 ms pacing, A2 WL < 7 cm during 460 ms pacing) can be defined. Therefore, the ICI group has the same atrial pattern as the AF group.

[A randomized double-blind trial comparing cibenzoline and disopyramide in the prevention of recurrences of atrial tachyarrhythmia]. / Etude randomisée en double aveugle comparant la cibenzoline et le disopyramide dans la prévention de récidives de tachyarythmies atriales.

The aim of this multicenter, randomised, double-blind trial was to compare the efficacy and tolerance of oral disopyramide (D: 250 mg slow release twice daily) compared with cibenzoline (C: 130 mg twice daily) in the prevention of recurrences of atrial arrhythmias over a 6 month period. Sixty patients (mean age: 62 +/- 14 years; 37 men, 23 women; cardiac disease in 60% of cases) were randomised to two groups: C (N = 31) and D (N = 29). The commonest arrhythmia was atrial fibrillation (83%). The arrhythmia was recent (< 3 months) in 41% of patients and present for more than one year in 38% of patients. Sixteen patients of Group C (52%) and 11 of Group D (38%) had recurrences after an average of 79 +/- 58 days for Group C and 58 +/- 40 days for Group D (p = NS). The probability of absence of recurrence at 6 months was 36 +/- 11% in Group C and 55 +/- 10% in Group D (p = NS). Four patients in Group C (13%) and 13 patients in Group D (45%) had at least one unwanted side-effect (p = 0.009). Treatment was stopped because of side-effects in 2 patients in group C (6%) and 6 patients in Group D (21%). These results show that cibenzoline has a comparable efficacy for the prevention of recurrence of atrial tachyarrhythmia and is significantly better tolerated than disopyramide. This differences is mainly related to the marked anticholinergic effects of disopyramide.

[Short and medium-term outcome after radiofrequency ablation of the atrioventricular junction]. / Evolution à court et moyen termes après ablation de la jonction auriculoventriculaire par courant de radiofréquence.

The aim of this retrospective study was to assess short and long-term mortality and morbidity after radiofrequency ablation of the atrioventricular junction in patients with supraventricular arrhythmias resistant to treatment. This cooperative series included 91 patients (47 men, mean age 68 +/- 9 years). The arrhythmia was paroxysmal in 56% of cases. The mean duration of symptoms was 67 +/- 61 months and 45 patients (49.4%) were in the NYHA Classes III and IV. An escape rhythm was present in 58 patients with a mean frequency of 39 +/- 9/min. Early complications were observed in 5 patients (venous thromboses, pulmonary embolism, mild pericardial effusion and haemothorax). The hospital mortality was 4 patients (4.4%). Death was of cardiac origin in 1 case (cardiac failure). The mean follow-up of patients was 14.5 +/- 8.6 months. Eleven patients died during this period, 8 of cardiac causes: cardiac failure (3 cases), sudden death (3 cases), thrombosis of a valve prosthesis (1 patient) and major electrolyte disturbances causing loss of stimulation in 1 case. Six patients had recurrences. Long-term morbidity was either related to cardiac pacing (3 cases) or cardiac failure (3 cases). Thirteen patients were in NYHA Classes III or IV at the end of follow-up. The authors conclude that radiofrequency ablation at the atrioventricular junction is an effective method of treating resistant supraventricular arrhythmias. Complications are not frequent but mortality appears to be high, probably due to the presence of advanced cardiac disease in the majority of cases. Sudden death seems to be rare and unrelated to pacing defects.

Long-term pacemaker dependency after radiofrequency ablation of the atrioventricular junction.

This prospective study was conducted to determine the percentage of patients with long-term pacemaker dependency after successful radiofrequency ablation of the atrioventricular junction. Abrupt inhibition of the pacemaker was performed 13.5 +/- 8.1 months after ablation in 59 patients. A > or =5-second asystole was considered to indicate pacemaker dependency. Pacemaker dependency was present in 18 patients. Absence of escape rhythm immediately after ablation was strongly associated with a higher incidence of long-term pacemaker dependency. The following variables were not associated with pacemaker dependency: age, presence of cardiac disease, presence of preablation bundle branch block, number of radiofrequency applications, a bilateral approach for ablation, and continuation of antiarrhythmic therapy after ablation. We concluded that (1) long-term pacemaker dependency is present in 30.5% of the patients after successful atrioventricular junction radiofrequency ablation and (2) absence of escape rhythm immediately after ablation predicts long-term pacemaker dependency.

Prospective evaluation of high-dose or low-dose isoproterenol upright tilt protocol for unexplained syncope in young adults.

The sensitivity of the passive head-up tilt test (HUT) in the evaluation of unexplained short-lasting syncope in young adults remains insufficient. The infusion of isoproterenol was proposed to improve the benefit. To evaluate the sensitivity-specificity relationship during isoproterenol dosing, we studied 76 young adults (aged 20.9 +/- 1.7 years) (group S) with recurrent (mean 3.8 +/- 1.6) losses of consciousness that remained unexplained after clinical and noninvasive assessment and 35 young healthy volunteers (aged 22.6 +/- 2.7 years) (group V). Subjects underwent either passive HUT (45 min, 60 degrees without drug dosing for 48 subjects in group S (S1) and 17 in group V (V1), or HUT with isoproterenol infusion at progressive doses (2 then 5 micrograms/min) after 30 minutes of passive tilting for 28 patients in group S (S2) and 18 in group V (V2). During passive HUT, the test was positive (asystole, bradycardia, or fall in systolic blood pressure) in 2 of 17 (11.8%) patients in group V1 and in 7 of 48 (14.6%) in group S1 before 30 minutes, and in 3 of 17 (17.6%) in group V1 compared with 10 of 48 (20.8%) in group S1 at the end of the 45-minute infusion, with no difference in delay before the appearance of a positive result. During HUT with isoproterenol dosing, the test was positive in 2 of 18 (11.1%) patients in group V2 and in 18 of 28 (64.2%) in group S2 before 45 minutes (2 micrograms/min; p < 0.01) in 7 of 18 (38.8%) in group V2 compared with 24 of 28 (85.7%) in group S2 before 60 min (5 micrograms/min; p < 0.01). In both cases the mean delay in evoking a positive response was significantly shorter. No asystolic response was observed in the volunteers regardless of the protocol used. The most characteristic response to isoproterenol injection was the appearance of a junctional escape rate with a fall in systolic blood pressure (61.5% of subjects in group S2). The infusion of isoproterenol considerably improves the sensitivity of the HUT with satisfactory specificity if low doses are used (< 3 micrograms/min). These results support the use of HUT with isoproterenol in the evaluation of unexplained syncope in young adults.

A randomized, single-blind crossover comparison of the effects of chronic DDD and dual sensor VVIR pacing mode on quality-of-life and cardiopulmonary performance in complete heart block.

The aim of this study was to compare DDD and dual sensor VVIR (activity and QT) pacing modes in complete AV block (CAVB). Eighteen patients (14 men and 4 women, aged 70 +/- 6.5 years) implanted with a dual chamber, dual sensor pacemaker for CAVB with normal sinus node chronotropic function were studied. A quality-of-life and cardiovascular symptom questionnaire, and a treadmill exercise test were completed after a period of VVIR and a period of DDD pacing, each lasting 1 month. Overall quality-of-life and cardiovascular symptoms did not significantly differ, though three patients felt discomfort during VVIR mode. There was no significant statistical difference in cardiopulmonary parameters. DDD and VVIR modes yielded the following respective data: maximum heart rate = 105.7 +/- 21.8 beats/minute versus 107.6 +/- 21.6 beats/minute (NS); maximum workload = 60 +/- 33.4 W versus 59.3 +/- 37.8 W (NS); treadmill duration = 10.1 +/- 3.8 minute versus 10.1 +/- 3.6 minute (NS); oxygen consumption at anaerobic threshold = 14.6 +/- 4.1 mL/kg per minute versus 14.9 +/- 4.6 mL/kg per minute (NS); maximum minute ventilation = 49.6 +/- 9L/min versus 46 +/- 12 L/min (NS); and respiratory quotient = 1.08 +/- 0.15 versus 1.08 +/- 0.13 (NS). We conclude that, during a 1-month follow-up period, no difference was found between DDD and dual sensor VVIR (QT and activity) pacing modes in CAVB patients with regard to quality-of-life and cardiopulmonary performance, though a trend toward an increased sense of well being was noted with the DDD mode.

[Multifactor prevention of endocarditis and cardiac pacemakers. A prospective study apropos of 207 patients]. / Prévention polyfactorielle des endocardites et stimulateurs cardiaques. Une étude prospective à propos de 207 patients.

Infections after cardiac pacemaker implantation are rare (0.13 to 12.6%) but potentially severe complications. Staphylococcus is the genus most frequently isolated (72 to 100% of cases). The use of systematic prophylactic antibiotics remains controversial. From November 1991 to October 1993, 207 consecutive patients were submitted to a series of measures designed to reduce the risk of infection: a) intravenous bolus injection of Cefamindole, 15 minutes before implantation, b) cutaneous disinfection with iodinated polyvindone, c) injection of an ampoule of rifampin before closure of the pacemaker in the pouch, d) absence of drainage system. Patients were predominantly female (60.9%), with a mean age of 77 +/- 10 years, frequently suffering from heart disease (53.8%). The indication for implantation was atrioventricular block (39.7%), carotid sinus syndrome (27.5%), atrial arrhythmia (27.5%), resection of the node-His tract (5.3%). This procedure corresponded to the first implantation in 88.4% or replacement of a previous pacemaker in 11.6% of cases and the pacing mode was single-chamber (38.4% or replacement of a previous pacemaker in 11.6% of cases and the pacing mode was single-chamber (38.7%), or double chamber (61.3%). The mean duration of the procedure was 51.5 min +/- 30 min. The mean follow-up was 12.7 +/- 5 months. The overall mortality was 14% (11 cases of cardiac failure, 6 sudden deaths, 4 cerebrovascular accidents, 4 cases of pneumonia, 4 neoplasms). Only one infectious problem (endocarditis, i.e. 0.48%) was observed.

[Mid-term outcome of escape rhythm after radiofrequency ablation of the atrioventricular junction]. / Evolution à moyen terme du foyer d'échappement après ablation par radiofréquence de la jonction auriculoventriculaire.

UNLABELLED: Mid-term outcome of the underlying escape rhythm developed after radiofrequency ablation of the atrio-ventricular junction was studied in 50 consecutive patients (28 women and 22 men with a mean age of 66.2 +/- 9.6 years). The escape rhythm was assessed immediately after ablation and after 13.7 +/- 8 months. At the end of ablation: an escape rhythm was present in 38 patients (76%), with a mean rate of 40.7 +/- 9.7 beats/min and a QRS morphology identical to the preablation QRS morphology in 22 patients (58%). At follow-up: an escape rhythm was present in 37 patients (74%), with a slower mean rate of 36.4 +/- 6.8 beats/min (p < 0.05) and an unchanged QRS morphology in 87.5% of the patients. Patients presenting with an escape rhythm at follow-up were more frequently found to have a postablation escape rhythm (p < 0.01). Escape rhythm presence at follow-up was not influenced by age, presence of a cardiac disease, continuation of an antiarrhythmic treatment after ablation, use of a bilateral approach for ablation or number of radiofrequency applications. CONCLUSION: after abrupt inhibition of the stimulation, an escape rhythm was present only in 74% of the patients 13.7 +/- 8 months after atrio-ventricular junction radiofrequency ablation. QRS morphology was identical to the preablation morphology in 57% of the patients.

[Characteristics and influence of different clinical forms on the development and prognosis of carotid sinus syndrome. Apropos of 215 cases]. / Caractéristiques et influence des différentes formes cliniques sur l'évolution et le pronostic des syndromes du sinus carotidien. A propos de 215 cas.

The carotid sinus syndrome is a well-known cause of syncope: the cardio-inhibitory forms are the easiest to diagnose and probably the easiest to treat. However, the vasodepressive forms are as common but their outcome is mainly unknown. Eight hundred and fifty-three patients underwent endocavitary electrophysiological studies with invasive blood pressure measurement for unexplained syncope between October 1984 and January 1990. A carotid sinus syndrome was diagnosed in 215 cases. Fifty-two patients (24.2%) had a cardio-inhibitory form (ventricular standstill > or = 3 s during carotid sinus massage), 40 (18.6%) had a pure vasodepressive form (isolated fall of systolic blood pressure > 50 mmHg during massage) and 123 patients (57.2%) had a mixed form. The average age was 74.1 +/- 9.7 years with no difference between the different forms. A number of parameters was different on the cardio-inhibitory and vasodepressive forms: the number of men (75.6 vas 24.4%; p < 0.05) and the number of syncopes (83.3 vs 60%; p < 0.02) were greater in the cardio-inhibitory form; the vasodepressive forms were more often associated with a history of transient ischaemic attacks (15 vs 0%), a poor cardiovascular status (hypertension: 47.5 vs 15.7%; p < 0.01), coronary artery disease (47.5 vs 25.5%; p < 0.05), cardiac failure (27.5 vs 11.7%; p < 0.05), induction of sustained supraventricular tachycardia (50 vs 23.5%; p < 0.05) and a greater pacemaker effect (53.6 vs 34.8 mmHg; p < 0.01); of the 191 patients (84.9% of the population) followed up for an average of 21.2 months, 168 received treatment: implantation of a cardiac pacemaker in 108 patients, reduction of antihypertensive and/or potentially bradycardia-inducing drugs in 30 patients, prescription of antiarrhythmic therapy, in 30 patients.(ABSTRACT TRUNCATED AT 250 WORDS)

[Emery-Dreifuss muscular dystrophy with major conduction disorders and cardiac excitability]. / Dystrophie musculaire d'Emery-Dreifuss avec troubles majeurs de la conduction et de l'excitabilité cardiaque.

The case of a 53-year-old patient with scapulo-humero-peroneal wasting, early flexion contractures of the elbows and ankles, abnormal cardiac conduction and probable X-related heredity is reported. Histology was suggestive of a primary and very slowly progressive muscular disorder. CT scan revealed fatty muscle degeneration which was more extensive than suggested by clinical findings. Electrophysiological studies revealed right atrial paralysis, left atrial tachycardia and supra and, above all, infra-His block. Sustained episodes of ventricular tachycardia, an anomaly described only rarely in pathology of this type, occurred some time after the fitting of a permanent pacemaker. The originality of this case of Emery-Dreifuss progressive muscular dystrophy lies in the usefulness of muscle CT scan and the existence of life-threatening arrhythmias.

[Symptomatic sinus dysfunction. A new use of electrophysiology]. / La dysfonction sinusale symptomatique. Une nouvelle utilisation de l'électrophysiologie.

The authors undertook a prospective electrophysiological study of 950 patients: 53 subjects considered to be "controls" since they were free of any history of syncope or faintness were identified, as well as 39 symptomatic subjects with a strong suspicion of sinus dysfunction, since no other detectable cause of fainting episodes was found by extracardiac investigation, 24 hour ECG nor electrophysiology. Following the creation of a computerised tool enabling not only the entry of indirect tests, processing, averaging of results, printing and memorization, but also assistance in interpretation, several electrophysiological parameters were used: heart rate and existence of sinus arrhythmia, Strauss tests with adjusted data or not, effective nodal refractory period, Guize, Narula and Mandel tests, and an atropine (0.03 mg/kg) test which was performed only in the symptomatic group. These tests were studied by single-variate and correlative analysis to define their normal ranges, their critical values and their dependence or independence. The performance of each test (i.e. its efficiency, and the specificity and sensitivity of each critical value) was measured. Tests found to be most useful (specificity and efficiency > 90%) were as follows: Mandel test = CSRT > or = 534 ms, Narula test = TECASA > or = 339 ms, heart rate < or = 55/min, type II, IIa and chaotic Strauss curve associated with a pathological Guize test. The combination of these tests in this algorithm resulted in an increase in sensitivity to 84%, at the price of a very moderate fall in specificity to 87%.(ABSTRACT TRUNCATED AT 250 WORDS)

[Measurement of pacemaker effect: incidences on the choice of pacing mode? A prospective and statistical study of 396 patients]. / La mesure de l'effet pacemaker: incidences sur le choix du mode de stimulation? Etude prospective et statistique de 396 patients.

Single ventricular stimulation induces haemodynamic disturbances, the best known of which is the pacemaker syndrome. In order to assess the prevalence and severity of these abnormalities, invasive blood pressure monitoring was performed in 396 consecutive patients undergoing endocavitary electrophysiological investigations: a decrease in systolic blood pressure at a rate near to that of the spontaneous rhythm defines the pacemaker syndrome. It is maximal after 3 to 5 beats of equivalent intensity with or without retrograde conduction. The pacemaker syndrome is greater in hypertensive and coronary patients than in subjects with healthy hearts (-44.2 mmHg and -37.2 mmHg versus -33 mmHg, p < 0.001 and p < 0.04). It is less pronounced in cases of cardiac failure (-31.8 mmHg). The pacemaker syndrome increases in intensity with age (-44.3 mmHg after 80 years of age versus -23.1 mmHg in subjects under 50 years of age; p < 0.001). Two electrophysiological abnormalities are associated with an increased pacemaker syndrome even in apparently normal hearts: sustained induced supraventricular tachycardia (-34.2 mmHg versus -26 mmHg, p < 0.002), mixed carotid sinus syndromes (-38 mmHg) and pure vasodepressive syndromes (-48.5 mmHg, p < 0.001). The study of the pacemaker syndrome is useful for three reasons: the detection of another cardiac abnormality in cases of sustained induced supraventricular tachycardia, even in an apparently healthy heart; to assess the presence of a second haemodynamic abnormality independent of the vagal effect in cases of carotid sinus syndrome with vasodepression; finally, to identify the patients at high risk of a pacemaker syndrome.

[Value of intravenous flecainide in electro-induced supraventricular arrhythmia. Apropos of 37 cases]. / Intérêt du flécaïnide en intraveineuse dans les troubles du rhythme supraventriculaires électro-déclenchés. A propos de 37 observations.

Thirty-seven patients presenting with electro-induced supraventricular arrhythmia sustained for more than 10 min or symptomatic received an intravenous injection of flecainide acetate (1.5 mg/kg; 10 mg/min). There were 24 cases of atrial fibrillation, 13 of atrial tachysystole with more than 180 beats per minute. Electrophysiological exploration was carried out for syncope (13 cases), lipothymia with palpitations (11 cases) or without palpitations (8 cases), or for a stroke of unknown origin. The induced arrhythmia was the only electrophysiological abnormality in 57% of cases. A return of sinus rhythm was obtained in 70% of cases during the injection (12 cases) or shortly after the end of the injection (14 patients). Safety was good, with the exception of the onset of two junctional rhythms and one case of non-syncopal monomorphic ventricular tachycardia. After an initial reduction, the PR, QRS, PA and HV intervals were significantly longer than baseline, whereas the AH space and the systolic blood pressure remained virtually unchanged. Thus the provision of IV flecainide acetate can only be beneficial in carrying out study protocols of abnormalities of the atrial substrate.

[Effects on the bone metabolism of long-term treatment with antivitamins K1]. / Retentissement sur le métabolisme osseux des traitements au long cours par les antivitamines K1.

Oral anticoagulants (OC) prevent the activation by carboxylation of coagulation proteins. However this action also affects osteocalcin, or bone Gla-protein, a parameter of bone remodelling. Phosphorus and calcium metabolism, osteocalcin levels and bone mineral content were studied in twelve men aged under 60, and who had been taking OC for more than a year, in comparison with a paired group of nine controls with the same cardiovascular pathology but not taking anticoagulants. Osteocalcin levels were lower in the OC group (3.44 ng/ml) than in the control group (5.88 ng/ml) (p = 0.01). There was no significant difference in other phosphorus/calcium balance parameters nor in bone density between the two groups. No evidence was found of any osteopathy in the OC group, but the decrease in serum osteocalcin could result either from inhibition of its secretion or of its carboxylation, or from an action on the osteoblast.

[Myocardial infarction in patients aged 70 years and over]. / Infarctus du myocarde chez les sujets âgés de 70 ans et plus.

109 subjects aged 70 years (58 women, 51 men; average age 77 years) were hospitalized in the CICU (Cardiology Intensive Care Unit) over the period stretching from 1984 to 1986. The average length of stay in the CICU was 1 week, completed by an average stay of 5 days in the cardiology department. 100 per cent of the patients were followed up. Of the clinical parameters made evident by this study, the authors note that hypertension was the predominant risk factor (52.2 per cent); a history of coronary disease was noted in 60.5 per cent; 26.6 per cent of the patients were hospitalized before the 6th hour, chest pain being typical in 78 per cent versus painless in 11 per cent of patients; topographically, the infarction was anterior in 55 per cent, posterior in 40.4 per cent, and around the circumference in 4.6 per cent of cases; 80.8 per cent of the infarctions were transmural versus 19.2 per cent of infarctions without the Q wave--the latter accounted for a higher hospital mortality rate (38 per cent versus 27.3 per cent). The main complications were disturbances in rhythm (60.6 per cent) and LVI (56.9 per cent). Complications on the form of infections were noted in 15.6 per cent. Apart from the usual indicators of severity (cardiogenic shock, VF, LVI), infarction of the RV and AF had a serious effect on the prognosis. latrogenic disease accounted for 18.9 per cent. From the point of view of prognosis, hospital mortality was 30 per cent; mortality after one year was 44 per cent and 47.7 per cent after 2 years (in a group of 76 subjects).(ABSTRACT TRUNCATED AT 250 WORDS)