HIS bundle electrogram in rheumatic mitral valve disease with special reference to Bachmann's bundle block in P mitrale

HBEs were recorded from either the right or left ventricle or simultaneously from both in 26 patients with chronic rheumatic mitral stenosis alone or in association with other mild valvular lesions during the diagnostic cardiac catheterization. Eleven of the patients had auricular fibrillation. Of the remaining 15 patients with sinus mechanism and P mitrale in the surface electrocardiogram, 12 were noted to have H potential preceded the termination of P wave and gave P2H interval of negative value- so-called "Bachmann's bundle block". Among these, double atrial activities (A and A' waves) could be identified on the HBE recorded from the left ventricular endocardial surface with catheter electrodes positioned at the subarotic region in 7 patients studied. Interatrial conduction time (P1A' interval) measured in these patients was prolonged in all and ranged from 47 to 82 with an average of 66 msec. Prolongation of intraatrial (or internodal) conduction time was noted in only one patient who also had first degree A-V block and prolonged A-H interval. There was no correlation of either P1P2 or P2H interval to the degree of left atrial enlargement. The P1P2 or P2H interval also had no correlation with hemodynamic parameters. In patients with auricular fibrillation, all impulses unable to conduct to the ventricle were blocked proximal to the His bundle and concealed conduction was not observed distal to it.

Gastric sarcoidosis presenting with haematemesis

Sarcoidosis is a very rare disease in Singapore. Sarcoid granuloma involving the stomach alone is even more rare, and only about 21 cases have been reported in the literature up to 1953 (Scott et alii, 1953). In a review of the literature, Wadina and Melamed (1966) found 34 cases of granulomatous involvement of the stomach, all purporting to be sarcoidosis. However, on closer examination of the evidence, many of these 34 cases of so-called sarcoidosis of the stomach were subject to doubt. Bleeding from gastric sarcoidosis is also rare, and only about eight cases have been reported in the literature up to 1970. The present report presents a further example of this rare cause of upper gastrointestinal bleeding and attempts to review the significance of sarcoid granulomas in the stomach.

Left ventricular approach for recording His bundle potential in man

The electrical potentials of the His bundle (HB) were recorded from the left ventricular endocardial surface in 28 patients ranging from 16 to 63 years of age. In 14 of the patients the left bundle branch (LB) potentials were also obtained. Placement of a bipolar electrode catheter tip toward the interventricular septum, right at and also 1 to 2 cm below the aortic valve, resulted in stable recordings of both potentials in successive cardiac cycles even at performing atrial or HB pacing from the right heart. The following intervals were measured in milliseconds (msec): P-A, A-H, H, H-V, LB, and LB-V. The average values in 12 patients (average age 26 plus or minus 7 years and average heart rate 90 plus or minus 16 beats per minute) with normal A-V conduction were as follows: P-A 28 plus or minus 7, A-H 76 plus or minus 16, H 19 plus or minus 3 and H-V 45 plus or minus 6 msec. The average values for LB and LB-V in 10 of these 12 patients were 15 plus or minus 3 and 25 plus or minus 3 msec respectively. Validation of the His bundle electrogram (HBE) from the left ventricular endocardial surface was based on simultaneous recordings of the intracardiac electrograms from both left and right sides of the heart in 18 patients. The individual average values for the intervals obtained from both sides of the heart in these patients were statistically not different, except that the H potential was slightly longer in duration fr m the left heart (P equals 0.05). Among these, 16 showed simultaneous onset of the H potentials, and the LB-V and RB-V conduction times from comparable points were almost the same. Indications for the left sided electro-physiologic studies include the following situations: (a) inability to record H from the right of the heart; (b) giant right atrium; and (c) possibly during atrial fibrillation.