Suraj P. Ahuja

Rifampicin-quinidine interaction

Abstract Many interactions have been described between rifampicin and other drugs. They include increased metabolism of warfarin, glucocorticoids and oral contraceptives, presumably by enzyme induction (Zilly et al. 1977). We report the first documented case of an interaction between rifampicin and quinidine.

Experimental coronary artery ligation in conscious dogs six months after bilateral cardiac sympathectomy

Abstract The effects of left circumflex coronary artery (LCA) occlusion six months after bilateral cardiac sympathectomy on mortality, arrhythmias, and myocardial norepinephrine were studied with functional and histologic assessment of sympathetic regeneration. Bilateral stellate ganglionectomy, thoracic sympathectomy, and ansectomy (BSTG) were performed on 23 dogs and denervation was confirmed by electrical stimulation. Six months later, the LCA was ligated by a two-stage technique in these dogs (BSTG-6 mo.) and 23 control dogs in the conscious state. All dogs were autopsied at death or after 48 hours. Mortality at 15 minutes from ventricular fibrillation (VF) was 22 per cent in BSTG-6 mo. dogs and 52 per cent in control animals (p

Platelet survival in patients with prosthetic heart valves

Abstract Chromium-51 platelet survival studies were carried out in 20 patients with a prosthetic heart valve. Only 1 of 10 patients with a prosthetic mitral valve had a significantly shortened platelet survival time, and the mean value of 8.3 ± 0.96 (±1 standard deviation) days was not significantly different from that of normal control subjects (8.9 ± 0.75 days). Four of 10 patients with an aortic prosthesis had a shortened platelet survival time, and the mean value of 7.8 ± 0.10 days in this group differed significantly from the normal control value (P

The initiation of ventricular tachycardia and fibrillation in experimental coronary artery occlusion

Abstract Ninety-four dogs were studied electrocardiographically following acute occlusion of the circumflex branch of the left coronary artery in an attempt to elucidate the electrogenesis of ventricular arrhythmias. In terminal ventricular fibrillation, T wave interruption was invariably present, occurring at the peak or on the downslope of the T wave, and was progressively greater in two thirds of the recorded episodes. In nonterminal ventricular tachycardia, T wave cutoff (present in only one fourth of the episodes) was found near the end of the T wave and was progressively less in successive cardiac cycles. The commonest type of T wave interruption associated with ventricular arrhythmias occurred when an extrasystolic T wave was interrupted by the QRS of the succeeding ventricular extrasystole (V by V type). This was not seen in isolated ventricular premature beats. The drop in arterial pressure was quantitatively related to the degree of T wave interruption.

Value of apex cardiography in the assessment of cardiac aneurysms

Abstract Ultralow-frequency displacement curves of anomalous precordial pulsations in 3 cases of postinfarction ventricular aneurysm were recorded simultaneously with an apex cardiogram. The tracing in the case of complete thrombotic obliteration of the aneurysmal sac was characterized by a double systolic peak and a brief rapid-filling wave terminating in a diastolic bulge. In contrast, the tracings of the other 2 cases, presumed to have no significant obliteration of the aneurysmal cavity, showed a sustained systolic thrust with a delayed peak and absence of a rapid-filling wave. A mechanism is postulated to explain the differences.

Apex cardiography in the elucidation of a double or multiple impulse apex beat

Abstract An atrial thrust, a bifid systolic impulse and a palpable diastolic bulge account for a double or multiple pulsation at the cardiac apex. Various causes and the mechanisms of production of these abnormalities of the apex beat were discussed. The role of the simultaneously recorded electrocardiogram, arterial and venous pulse tracing, apex cardiogram and phonocardiogram in the elucidation of this cardiac sign was demonstrated. It is to be hoped that an intelligent palpation of the precordial movements, often neglected, will become an integral part of the physical examination in the differential diagnosis of heart disease.

Atraumatic study of left ventricular events following acute myocardial infarction

Time intervals of left ventricular dynamics were studied by a noninvasive polygraphic technique in 27 patients with proved acute transmural myocardial infarction. Contrary to previous reports, no statistically significant deviation from the normal was observed in systolic time intervals. However, there was a prolongation between the onset of ventricular depolarization and mechanical activity, the electromechanical interval. This seemed to disappear slowly during the healed phase of myocardial infarction. The origin of this abnormality is, at present, conjectural.

Further observations on the genesis of early systolic clicks: An intracardiac phonocardiographic study in a case of absence of the pulmonary valve

Abstract An early systolic click was heard in a 6 year old child with surgically produced absence of the pulmonary valve. Analysis of the external and intracardiac phonocardiograms pointed to the dilated pulmonary artery as the seat of origin of the extra sound.