Primary Testicular Pre-B Lymphoblastic Lymphoma.

Primary testicular lymphoblastic lymphoma is a rare entity. We report a case of a 13-year-old boy referred with unilateral testicular swelling. After preliminary work-up orchiectomy was performed Histopathology detected primary testicular lymphoblastic lymphoma.

Extra long PR intervals.

This case review presents various manifestations of extra long PR intervals, an interesting form of atrioventricular (AV) block first described in 1977. All patients in this study had organic heart diseases and various combinations of multilevel conduction impairment. Perhaps the most common cause of chronic AV conduction impairment is the ill-defined degenerative and/or fibrotic damage to the intraventricular conduction system.

Doubling of the ventricular rate by interpolated junctional extrasystoles resembling supraventricular tachycardia.

In a study of seven cases of paroxysmal supraventricular tachycardia, it was noted that the fast rate was not caused by the mechanism of rapid firing, reentry, or dual atrioventricular nodal conduction but by an abrupt doubling of the rate by interpolation of junctional extrasystoles between adjacent sinus beats while the sinus mechanism remained undisturbed. Dual ventricular response to a single atrial depolarization was seriously considered in each case. The intervals separating the junctional extrasystoles tended to be quite fixed, thus conforming to the pattern of junctional parasystole with an intrinsic rate very close to the rate of the dominant sinus rhythm.

Alternating bundle branch block together with alternation of PR intervals: advanced Mobitz II atrioventricular block.

Certain electrocardiographic patterns are well recognized for their propensity to progress to more severe forms of atrioventricular (AV) block, thus requiring pacemaker implantation. This article presents an infrequently recognized and deceptively benign pattern of conduction abnormality with great potential for advancement to severe AV block and necessity for pacemaker therapy. The pattern consists of alternating bundle branch block (BBB) in unison with alternation of the PR interval so that the right BBB beats and left BBB beats appear to be wedded to their own but different PR intervals.

Verapamil-mediated atrioventricular nodal reentrant tachycardia and the uncovering of dual-pathway AV nodal conduction.

In a 67-year-old man with multiple myocardial infarctions in the past, the use of oral verapamil for control of angina pectoris was followed by the appearance of two previously undiagnosed abnormalities, namely, a dual-pathway AV node conduction pattern, and paroxysms of AV nodal reentrant tachycardia precipitated by premature ventricular beats (PVB). It is probable that the differential effects of verapamil on the fast and slow AV node pathways, and the interplay of PVB with its concealment within the AV node, created the necessary circumstances in the AV node to precipitate the tachycardia. Observed off verapamil over several months, the patient remained in normal sinus rhythm but continued to have numerous premature ventricular beats (PVB's).

Intermittent fascicular extrasystoles producing pseudo AV block: electrophysiologic effects of beta agonists and antagonists.

This report describes a patient with pseudo-type II second-degree AV block due to an intermittent parasystolic focus located in the left bundle branch. A paradoxical increase in the fascicular rate was seen following intravenous propranolol, and fascicular extrasystoles were suppressed after intravenous isoproterenol treatment. All propagated fascicular extrasystoles were conducted to the ventricle with incomplete or complete right bundle branch block and a decrease in the H'-V interval compared to the H-V interval during sinus rhythm.

Mechanically mediated pacemaker pseudomalfunction.

A case is described of pacemaker pseudomalfunction caused by intermittent displacement of the ventricular lead. The displacement was shown to be caused by critically timed atrial contractions, dislodging the looped ventricular lead, and resulting in intermittent failure to stimulate the heart.

Noninvasive detection of active pericardial bleeding using cardiac blood pool scintigraphy.

The diagnosis of active pericardial bleeding has traditionally depended on an invasive documentation by needle aspiration, angiography, or direct inspection. Blood pool scintigraphy performed in 2 patients just before and after the development of hemopericardium revealed unique images in which acute pericardial bleeding manifested itself by an additional blood pool adjacent to the cardiac chambers. With appropriate attention to technical factors, such distinctive images should be highly specific for active bleeding into the pericardial sac.

Myocardial performance and N2O analgesia in coronary-artery disease.

Inhalation of 40 per cent N2O by nine patients who had occlusive disease in two or more coronary arteries with elevation of left ventricular end-diastolic pressures (LVEDP) significantly decreased arterial pressure (average 5 per cent) and myocardial contractility as measured by dP/dt/CPIP (average 14 per cent), and increased LVEDP (average 21 per cent). N2O had no significant effect in four patients who had angina without angiographically demonstrable coronary arterial disease. It is concluded that N2O depresses myocardial function in patients who have occlusion of the coronary arteries and impaired left ventricular function.

Prolonged His-Q interval in chronic bifascicular block. Relation to impending complete heart block.

Although prolonged infra-His conduction time in bifascicular block is suspected of denoting trifascicular disease, adquate documentation is lacking concerning the correlation between lengthened His-Q interval (H-Q) and the risk of development of complete heart block (CHB). H-Q in conducted sinus beats in patients with bifascicular block associated with Mobitz II or intermittent CHB represents the approximation of maximal H-Q prolongation prior to onset of trifascicular block. To assess this relationship between prolongation of H-Q and trifascicular block, His bundle electrocardiography (HBE) was performed in 50 patients with chronic bifascicular block exhibiting Mobitz II block or transient CHB.

Electrophysiologic properties of perhexiline.

Perhexiline maleate (Pexid), a promising clinical antiarrhythmic and antianginal drug, was evaluated for its electrophysiologic effects on the entire conduction system of the intact canine heart throughout a wide range of therapeutic and potentially toxic doses. Intracardiac conduction times were measured by bipolar intramyocardial and transvenous endocardial electrodes before and following the intravenous administration of each dose of perhexiline maleate, 3 mg/kg every 30 min for a total of 4 doses in 7 open-chest anesthetized dogs. Eight animals served as controls in which similar operative technique and electrophysiologic variables were recorded after infusion of the maleate diluent.

Calcified left ventricular aneurysm and non-atherosclerotic myocardial infarction in a child.

A 14-year-old boy, admitted with intractable chest pain, was found to have an enlarged heart and calcification in the apical region, with electrocardiographic features of massive inferolateral myocardial infarction. Left ventricular angiography revealed a large left ventricular aneurysm. He died following resection of the aneurysm and post mortem examination showed changes of a non-specific chronic myocarditis.

Lack of sensing by demand pacemakers due to intraventricular conduction defects.

A previously unrecognized form of failure of normally functioning noncompetitive R-inhibited or R-triggered pacemakers to sense is described in 30 patients. The failure was produced by the delayed arrival of ventricular depolarization due to intraventricular conduction disturbances at the site of pacemaker sensing electrodes. These patinets with late activation of the right ventricle exhibited right bundle branch block (RBBB) during conducted sinus beats or had ectopic beats arising from the left ventricle.