Showing papers by "Elliott M. Antman published in 1979"

Low-Pressure Cardiac Tamponade

Abstract: An elderly man developed cardiac tamponade from a tuberculous pericardial effusion but without such typical manifestations as pulsus paradoxus and jugular-vein distension. This case illustrates the difficulties in clinical recognition of low-pressure cardiac tamponade, which can develop in the presence of dehydration and hypovolemia. The hemodynamic factors that account for this phenomenon are discussed.

Physiologic determinants of the electrocardiographic diagnosis of left ventricular hypertrophy.

Abstract: The relative importance of left ventricular (LV) geometry, wall thickness, and mass on the inscription of left ventricular hypertrophy (LVH) on the ECG was examined in 93 patients; 36 had no LVH on the ECG, 10 had borderline voltage for LVH, and 47 had LVH on the ECG. LV cineangiograms in the right anterior oblique projection were analyzed for LV end-diastolic volume, free wall thickness (h), semiminor radius (R), LV mass index (LVMI), and the geometric relations described by h/R, mass/volume, and h . R. Although mean LVMI was greater in patients whose ECG voltage was either borderline or diagnostic of LVH, increased LVMI also occurred without LVH on the ECG. None of the variables (h, R, h/R or mass/volume) reliably indicated when LVH would be inscribed on the ECG. The product of h . R, however, defined three electrocardiographic groups; all patients with LVH on their ECG had h . R greater than 2.6 cm2. Wall thickening sufficient to result in an increased LV mass did not result in LVH on the ECG unless sufficient concurrent chamber dilatation was present. Thus, a critical geometric relationship resulting from the interplay of wall thickness and chamber dilatation is necessary for LVH to appear on the ECG. This finding is consistent with the solid-angle theory of electrocardiography as it relates to ventricular hypertrophy.

Continuous monitoring for ventricular arrhythmias during exercise tests.

Abstract: Exercise stress testing is being increasingly used to verify exerciseinduced arrhythmia and to aid in assessing antiarrhythmic drug efficacy. The true prevalence of ventricular arrhythmia during exercise testing is underestimated by means other than continuous monitoring. We compared the yield of ventricular premature beats (VPBs) between a continuous recording system ("trendscription") and intermittent monitoring among 39 patients undergoing a total of 50 consecutive exercise studies. By intermittent monitoring, 22 (44%) of 50 of the exercise tests demonstrated VPBs; with trendscription, 31 (62%) exhibited such arrhythmia. Most striking, however, was a sixfold increase in the disclosure of complex and repetitive forms of VPBs (56 vs nine episodes). Thus, this form of monitoring presents a cost-efficient, on-line method that allows concentration on the patient during exercise as well as clear recording of all arrhythmic events. (JAMA241:2802-2805, 1979)