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The electrocardiographic appearances and the significance of right bundle branch block were described at the beginning of the 20th century. Typical appearances include prolongation > 0.12 s of the QRS complex, RR' or rR' or Rr' appearances in V1 and widened S waves in the leads exploring the left ventricle (SI, aVL, V5 and V6). A delay in the appearance of the intrinsic deflection > 0.08 s may also be observed in the right precordial leads and negative T waves with ST depression may be seen in V1 and sometimes in V2. Left axis deviation of the QRS complex greater than - 45 degrees suggests associated left anterior hemiblock. Right axis deviation beyond + 120 degrees is equivocal. The principal differential ECG diagnosis is the Brugada syndrome, a familial arrhythmogenic autosomal dominant cardiomyopathy of variable penetration. This diagnosis is suggested when ECG abnormalities are observed in patients with a personal or family history of sudden death. Right bundle branch block only seems to have haemodynamic consequences in cardiac failure with associated asynchrony of the left ventricle or in certain cases of right ventricular dilatation encountered in congenital heart disease. The prognosis of right bundle branch block in the absence of underlying cardiac disease is good but it may be poor in other cases, particularly coronary artery disease. Moreover, the prognosis of right bundle branch block to complete atrioventricular block is rare in the absence of associated cardiac disease.

The consequences of implanting an automatic cardioverter defibrillator (ICD) on vehicle driving in France are poorly known. This retrospective study examined the behaviour at the wheel of ICD recipients who were recommended to abstain from driving for 3 to 6 months after device implantation. The study population included 98 patients (mean age = 59.5 +/- 14.8 years) followed for a mean of 24. +/- 23.9 months, who underwent ICD implant for ventricular tachycardia (65% of patients ventricular fibrillation (15%), syncope (8%), as part of a research protocol of myocardial cell transplantation 6%, or for primary prevention (5%). The underlying heart disease was ischemic in 59% of patients dilated cardiomyopathy in 11%,hypertrophic cardiomyopathy in 8%, valvular in 6%. Brugada syndrome in 4%, right ventricular arrhythmogenic cardiomyopathy in 2%, and miscellaneous disorders in 9% of patients. Five patients died without post mortem interrogation of the ICD. Only 28% of drivers remembered, and 13% observed, the recommended driving limitations. However, 45% (the oldest) claimed to drive prudently. During follow-up, 47% of patients received an ICD shock. Their mean it ventricular ejection fraction was 34 +/- 14%, versus 43 +/- 18% in patients who received no ICD therapy (p = 0.015). Syncope occurred in 16% who received ICD shocks. Shocks were delivered during driving in 6 patients, without consequent accident. Despite their non-observance of recommended driving limitations. ICD recipients suffered few traffic accidents. Legislation in France should reproduce the guidelines issued by European professional societies and enacted by the British laws.

Aerobatics is an aerial sport which has many physiological constraints, principally cardiovascular, with a risk if not adapted of sudden mid-air incapacity which could jeopardise aviation safety, and thus justifies the selection and surveillance of pilots. The aeronautical constraints during flight are multiple, related to the environment traversed, how the aircraft functions and its movements. Those which cause accelerations (+G in particular) pose the problem of haemodynamic tolerance because they can induce loss of consciousness due to cerebral hypoxia. Tolerance of acceleration varies among individuals; it can be improved with training, certain protective manoeuvres, and is reduced by hypoxia, certain medications, dehydration and heat. Moreover, in aerobatics certain tricks require manoeuvres which reduce this tolerance to +G accelerations. This is the "push-pull" effect (_G acceleration immediately followed by +G acceleration). This leads to a risk of sudden loss of consciousness with a load factor much lower than that which the pilot knows he is capable of tolerating. Besides the haemodynamic effects, the existence of an actual acceleration cardiomyopathy has been suggested but has not been proven in man. Finally, while changes in cardiac rhythm during accelerations are usual and relate to changes in vaso-sympathetic balance, ventricular and supra-ventricular rhythm disturbances are rare and are related to the intensity and duration of the acceleration.

The authors report 3 cases of resuscitated sudden death in which the investigations clearly showed coronary spasm. This was demonstrated by systematic coronary angiography with an ergometric test. Two patients underwent electrophysiological investigations which were normal. The three patients were prescribed long-term calcium antagonist therapy and one of them underwent coronary angioplasty. With a follow-up of 6 months to 3 years, there was no clinical recurrence or documented arrhythmia. A review of the literature shows that this is a cause of sudden death which is probably underestimated and unrecognised. Electrophysiological investigations often give disappointing results and medical therapy is the keystone of treatment. Coronary angioplasty and implantation of an automatic defibrillator are second-line treatments reserved to forms refractory to medical therapy.

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)

This study reviewed the clinical histories of 148 coronary patients aged 34 +/- 5 years (20-40 years) documented in the same cardiology unit. Myocardial infarction was the presenting condition in 114 patients (77%): inaugural 65%, with prodrome 7%, asymptomatic 4%. The presentation was angina pectoris in 32 patients (22%): effort angina 15%, unstable angina 7%. Two patients had other symptoms (1%). The coronary lesions were significant (greater than 50%) in 112 patients (77%) which included 41% single vessel diseases and 36% multiple vessel diseases. The coronary lesions were insignificant in 10 patients (7%) and absent in 21 (15%) (33% under and 11% over 30 years of age). After an average follow-up of 48 months (range 1 to 10 years), 20 of the 32 patients presenting with angina developed myocardial infarction and 6 had episodes of unstable angina (65% in the first year following diagnosis). Six patients had no serious coronary events, but thereafter, 3 died. Fifteen patients (47%) are asymptomatic (including 8 after coronary bypass surgery). Ten patients are symptomatic. Of the 114 patients with inaugural myocardial infarction, 3 have died, 67 (58%) are symptomatic; the average number of risk factors per patient was related to age and to the degree of coronary artery disease. The left ventricular ejection fraction was significantly higher in asymptomatic patients than in those who had presented a coronary event after myocardial infarction.(ABSTRACT TRUNCATED AT 250 WORDS)