[2 or 3 level blocks in the Tawara node during atrial tachycardia]

In atrial flutter (or paroxysmal atrial tachycardia), the ventricular response is dependant on the passage through 3 superposed zones of conduction in the Tawara node, the zone of decremential conduction being the central zone N. When the ventricular response is between half and a quarter of the atrial rate there are two possible explanations: type B alternate Wenckebach period (mobitz I block in the central zone N, 2/1 block at the nodo-ventricular junction) or type A alternate Wenckebach period (Mobitz I block in the central zone N and 2/1 block at the atrio-nodal junction). These two responses may alternate in the same patient depending on the drug therapy or vagal activity due to a phenomenon similar to the "GAP" phenomenon. Inexactitudes in the working out of the arithmetic formulae may easily be explained by a certain degree of concealed conduction of blocked activation in one zone or more rarely by hisian extrasystoles. Type A alternate Wenckebach periods are always easier to construct than type B. Perfect 3/1 atrial flutter can only be explained by a type B alternate Wenckebach period with a 3/2 period with a 3/2 period in the N zone and a 2/1 block in the NH zone. When the ventricular rhythm is permanently very slow or when the RR intervals are greater than four times the atrial cycle, 3 zones of block are usually at issue (the third being located in the inferior part of the node or superior part of the bundle of His). Examples of 5/1, 6/1 flutter are thereby analysed. Rapid atrial pacing after termination of the atrial arrhythmia allows a better analysis of its mechanism and the successive reproduction of conduction defects in each zone of block.

[Pulmonary arterial hypertension caused by neoplastic thrombosis of the pulmonary artery]

Neoplastic thrombosis of the pulmonary artery is a rare and little known cause of pulmonary arterial hypertension. The clinical picture is one of acute respiratory failure and progressive right ventricular failure caused by pre-capillary pulmonary hypertension. In the living patient there is no way of distinguishing this condition from that of subacute cor pulmonale due to embolism, especially as the primary tumour is not always found either because it is too small or because it has already regressed by the time it has metastasised. The diagnosis usually rests on histological examination of the lungs, and two pathological types can be distinguished: carcinomatous lymphangitis with secondary invasion and thrombosis of the pulmonary arterioles on the one hand, and the neoplastic arterial emboli of a chorio-epithelioma on the other.

[The atrial arrhythmia syndrome of vagal origin]

Having observed 18 cases, the authors describe a syndrome of recurrent paroxysmal atrial arrhythmia which was very homogeneous from the clinical and ECG point of view. It was usually found in middle aged males, with no demonstrable underlying heart disease, whose disorder of intra-atrial conduction occurred during sinus rhythm. The condition developed slowly over the course of years towards a maximum incidence of several short daily attacks of an arrhythmia which alternated between an atrial fibrillation and atrial flutter. Vagal overactivity is the precipitating cause of these attacks which are usually not completely nocturnal. The condition never progressed to sino-atrial block nor to permanent fibrillation. The beginning of each attack, often heralded by atrial coupling with a long enough interval to cause re-entry, is accompanied by slowing of the sinus rate down to the threshold level. The vagal effect of shortening the action potential and refractory period is recognised to be non-homogeneous in the atrial wall, and suggests a re-entry mechanism rather than hyper-excitability. This would explain the usual resistance of atrial arrhythmias of vagal origin to digitalis, beta blockers and quinidine. Amiodarone alone is usually effective because of the prolongation of the action potential which it causes. In 5 particularly resistant cases a good clinical result was obtained by the insertion of an atrial pacemaker with a fairly rapid rate.

[An unusual type of mid-ventricular obstruction. A discussion of the findings]

The authors report a case of left-sided mid-ventricular obstruction which was completely different from the usual type of obstructive cardiomyopathy, and had asymetrical hypertrophy of the septum demonstrable both by angiocardiography and macroscopically. Complete clinical and haemodynamic recovery followed left ventricular myectomy with replacement of the mitral valve (one year's follow-up).

[Biventricular massive infarction with rupture of a mitral papillary muscle and a tricuspid papillary muscle]

The authors report the case of a man of 62 who was admitted with a clinical and electrocardiographic picture of a posterior infarction which was very soon complicated by collapse and anuria. The findings on catheterisation of the right side of the heart were as expected. The cardiac index was very low, and the major abnormality was a type of adiastole with equal pressures in the right ventricle and the auricle of the right atrium. Despite an attempt to assist the circulation by an intra-aortic ballon, the patient died within a few hours. The postmortem examination confirmed the presence of a massive infarction of the left ventricle, but also of the right ventricle, together with rupture of the posterior papillary muscle of the mitral valve, and ischaemic rupture of one papillary muscle of the tricuspid valve.

[Emergency treatment of mechanical complications of acute myocardial infarction. Septum perforations and mitral insufficiency]

Over the last three years, thanks on the one hand to improvements in surgical techniques and ressuscitation, and on the other to assisted circulation using the intra-aortic balloon, which allows improved preoperative preparation of the patients, urgent medicosurgical treatment of the mechanical complications of infarction has improved the prognosis by comparison with the recent past. During the above period, our figures for operative intervention during the first two weeks after an acute infarction have been as follows: 1. Twenty nine cases of septal perforation (17 of which had previously had assisted circulation by balloon): there were 8 immediate deaths and 8 successful cases (no secondary deaths over a follow-up period of from 2 to 41 months). In all these cases, the surgeon approached the perforation by way of the left ventricle. No patient required an additional bypass procedure. Where indicated, assisted circulation by means of a balloon should not be continued for more than a few days. If there is no improvement with its use, it seems unreasonable to proceed to surgery regardless. 2. Ten cases of acute mitral incompetence; 8 were due to ruptured papillary muscle and two to mal function. 5 patients out of the 10 had required circulatory assistance by balloon preoperatively. There were 2 immediate deaths and 8 successful cases, with one secondary death (follow-up period of between 2 and 37 months).

[Rupture of the papillary muscles of the mitrale valve during myocardial infarction]

Between 1967 and 1976, 13 cases of papillary muscle rupture during the acute phase of myocardial infraction were collected. Six patients have been treated surgically during the past three years. Three could undergo surgery by virtue of the use of an intra-aortic counterpulsion balloon. There were no operative deaths. One patient died ten days after surgery as a result of a neurological complication; while a second died 4 months after a successful operation of an undetermined cause. For very satisfactory results were obtained with a follow-up of 7, 16, 18 and 18 months.

[Treatment of junctional paroxysmal tachycardia, without patent Wolff-Parkinson-White syndrome, by sectioning an accessory Kent-His bundle]

The authors report the case of a patient suffering from a Bouveret's tachycardia without syndrome of Wolff-Parkinson-White. The analysis of the tachycardic spells however showed that during a reciprocal crisis, the circuit went through a left accessory ventriculo-atrial bundle, functioning only in the reverse direction. This accessory bundle was successfully cut by the surgeon, following the procedure of wide atrioventricular desinsertion as described by the authors of Duke University for the surgical treatment of the Wolff-Parkinson-White syndrome.

'Incessant' tachycardias in Wolff-Parkinson-White syndrome. II: Role of atypical cycle length dependency and nodal-his escape beats in initiating reciprocating tachycardias

Descriptions of patients with the Wolff-Parkinson-White (WPW) syndrome and reciprocating tachycardia in whom the initiation of the arrhythmia depended neither on the occurrence of premature beats nor on antecedent cycle-length shortening are given. In 5 the occurrence of escape beats in the bundle of His, usually in the presence of sinoatrial disease, activated the tachycardia circuit, but in the other 2 there were unusual mechanisms related to bradycardia-dependent block in the anomalous pathway, and delayed response to shortening of the atrial cycle length, respectively. Careful assessment of such mechanisms is essential for the correct choice of antiarrhythmic prophylactic therapy.

[Isolated ventricular tachycardia without patent cardiopathy]

The authors have made a further study of the case notes of 49 patients who were followed up for several years with isolated ventricular tachycardia occurring in a heart which was otherwise healthy; such tachycardias are also called essential or idiopathic. First they define the criteria necessary for the diagnosis of essential ventricular tachycardia: -- an arbitrary age criterion (less than 45 years in men and 50 years in women) which seeks to exclude the so-called "arterial" ventricular tachycardias; -- a follow-up period of supervision of more than two years, which excludes certain primary cardiomyopathies whose presenting feature is a series of attacks of ventricular tachycardia. They then attempt to classify the ventricular tchycardias into four types, according to their clinical features and the electrocardiographic tracings at rest and on exercise, and to predict the prognosis. The most frequently encountered and benign type was the classical ventricular tachycardia of Bouveret.

[Massive tricuspid insufficiency during idiopathic dilatation of the right atrium. Surgical treatment. Apropos of two cases]

Tricuspid incompetence occuring in isolation is extremely rare, and had only been described under certain very particular conditions: trauma, septicaemia of genital origin, intravenous injection of narcotics. Idiopathic dilatation of the auricle of the right atrium is a disorder which has been described during the last fifteen years or so, and is recognised mainly because of the disorders of rhythm which it causes. These two cases demonstrate that, in the long-term, massive dilatation of the auricle can lead to tricuspid incompetence by dilating the ring, and require surgical intervention.

[Paroxysmal tachycardia due to a latent Wolff-Parkinson-White syndrome]

The authors studied 35 cases of Bouveret type paroxysmal tachycardia with normal baseline ECB, without any signs of Wolff-Parkinson-White syndrome. In more than half the patients, it seems that it may be stated that the paroxysmal tachycardia is related not to a reciprocal intranodal rhythm, as is said classically, but to a reciprocal rhythm using in the anterograde direction the normal pathways and in a retrograde direction a direct atrio-ventricular bundle in which only retrograde conduction is possible. This explains the absence of any patent preexcitation pattern on tracings in sinus rhythm. The authors particularly stress the value of a sign recorded at the onset of an attack of tachycardia: transient slowing of the rate of the tachycardia when functional bundle branch block is present can only be explained by the existence of a latent preexcitation bundle on the side of the "slowing bundle branch block".

[Paroxysmal junctional tachycardia. Determination of the inferior point of junction of the reentry circuit. Dissociation of the intra-nodal reciprocal rhythms]

Stimulation of the bundle of His and of the uppermost portion of the interventricular septum gives us an opportunity to make a precise study of capture phenomena in patients with paroxysmal nodal tachycardia. According to whether the capture is correctly timed, delayed, or unusually premature, the inferior junction point of the reentry circuit can be located precisely by reference to the H wave and the onset of the R wave. Out of a series of 65 patients, only 30 of whom had a true WPW syndrome, it was shown that 43 cases had a bundle of Kent which ensured retrograde conduction during the tachycardia, and was therefore the seat of a unidirectional block in 13 cases. In 22 cases (33.8%) the diagnosis of WPW syndrome was excluded, but the reentry circuit was nevertheless not of nodal origin. The inferior junction point of the circuit was effectively situated between H and R in 12 cases, and at H in 5. In only 5 cases (7.8%) might there have been a reciprocal intra-nodal rhythm, which should not necessarily be taken as proof of its existence. The validity of the classical criteria in localising the reentry circuit is discussed.

[Tachycardia caused by reciprocal rhythm between normal pathways and a rapid atrial-His pathway]

Report of one unhabitual case of reciprocal rhythm with anterograde conduction through James' fibres and retrograde conduction through the normal nodal pathways. The reality of an anterograde nodal short-circuit is indicated by many arguments, and in particular by the presence of a double ventricular response, after induced atrial premature beats reaching the ventricle once by the rapid pathway and the second time by the slow pathway.

[Apparent auricular paralysis and disorders of auriculo-ventricular conduction. anatomo-clinical study]

Correlation between the endocardial electrocardiographic recording and the histological findings of the conduction pathways in one case of apparent atrial standstill makes it possible to state the following facts: 1. The presence of a supranodal block through an intraatrial conduction disturbance. 2. The presence of James' fibres by-passing the upper part of Tawara node. 3. The functional character of these James' fivres which constitute, in view of the presence of lesions of the upper part of the Tawara node, the only possible pathway from the atria to the ventricles in this case. 4. The possibility to record the action potentials of James' fibres in that exceptional case. The histological examination made it possible also to recognize the anatomical lesions responsible for the idiopathic dilatation of the right atrium and of the apparent atrial standstill which represented the end-stage of an atrial rhythm disease.

[Septal perforation of myocardial infarct. Progress and limitation of current treatment. Apropos of 28 recent cases]

The emergency treatment of septal perforation in a myocardial infarction was markedly improved by pre-operative preparation of the patient by an intra-aortic balloon. If one excludes 7 cases in which the favourable immediate course made possible a delayed operation, 21 cases, severe from the start, were observed in the last two years: 8 patients, were thought to be operable with 6 successes. The type of the patient, the age, the associated diseases, the gravity and extension of the local lesions explain that this complication nevertheless still remains very often beyond the present possibilities of the medical-surgical treatment.

Wolff-Parkinson-White syndrome. Problems in evaluation of multiple accessory pathways and surgical therapy

Total atrioventricular bypass (Kent bundle) does not explain all the findings in some cases of Wolff-Parkinson-White (W-P-W) syndrome. Two cases are reported in which two accessory pathways, set in series or in parallel, could be demonstrated. In case 1, a short P-R interval, gap phenomenon, and presence of delta wave with either a short or long P-R interval suggested the hypothesis of an atrio-His accessory path (James fibers). The presence of a type-B delta wave during His stimulation demonstrated the takeoff of another bypass (Mahaim fibers) below or at the point of stimulation. The His-ventricle accessory path had a supernormal phase of conduction during either atrial or His stimulation. In case 2, the rapid spread of the impulse to the His bundle (P-H 65 msec) was responsible for a normal H-R interval (35 msec) during either reciprocating tachycardia or normal sinus rhythm wtih a nonwidened QRS and minimal W-P-W deformity (partial cancellation of the delta wave). During reciprocating tachycardia, alternatively short and long P'-H intervals with constant H-R (His bundle) and R-P' (Kent bundle) were due to alternate antegrade atrio-His conduction through the atrionodal nodal bypass (James fibers) and the A-V node. Surgical findings confirmed the existence of a left bundle of Kent. The division of the His bundle resulted in a maximal W-P-W deformity (type A) and abolished the reciprocating tachycardia.