Echocardiographic Aspects of Restrictive Cardiomyopathy

Background and Methods: We studied 17 patients with restrictive cardiomyopathy; eight had biventricular restriction (type A), four had left ventricular restriction (type B), and five had only right ventricular restriction (type C). Results: Type A disease was characterized by pulmonary and systemic venous congestion. The restrictive pattern was found in the inlet of both ventricles. Both atria were enormous, with small or normal-size ventricles. Differential diagnosis included constrictive pericarditis and systolic pump dysfunction. Type B restriction disease was characterized by venous pulmonary congestion, pulmonary hypertension, and important dilatation of the left atrium and right cavities with a small or normal-size left ventricle; the restrictive pattern was found only in the affected left ventricle. Conclusions: The clinical picture resembles that of rheumatic mitral valve disease with right ventricular failure. Type C disease had restriction only in the inlet of right ventricle, with giant right atrium, systemic venous hypertension with low flow, and normal pressure of pulmonary artery and left heart. Differential diagnosis included Ebstein's anomaly of tricuspid valve. The etiology of type A disease was amyloid, endomyocardial fibrosis of ventricles and idiopathic interstitial fibrosis. Asymmetric types were always caused by Davies' disease.     

Observations After Laryngo-Pharyngectomy

This paper records our observations and inferences followinglaryngopharyngectomy performed on 30 cases at the Tata MemorialHospital. The incidence of local recurrence after surgery is high. Preoperativeradiotherapy, given to 76% of our cases, did not significantlyreduce the incidence of local recurrences. It would perhapsbe more profitable to remove the disease primarily by surgerywhere possible, and follow with postoperative radiotherapy todecrease the incidence of local recurrences, as inferred fromcomparative studies. Stress is also placed on the wide removalof the primary during surgery rather than to concentrate onnode metastases. An elective or prophylactic cervical blockdissection did not reduce the incidence of local recurrencebut increased the postoperative morbidity. In a developing country, speech is a major and important meansof communication. The development of useful speech soon aftersurgery, with the use of external vibrators and voice tunnels,has helped to rehabilitate these patients at an early stage.     

POSTOPERATIVE ANALGESIA WITH EXTRADURAL CLONIDINE

The analgesic effect of extradural clonidine was evaluated ina double-blind study. In the recovery room, following orthopaedicor perineal surgery 20 ASA I and II patients were allocatedrandomly to two groups. The extradural clonidine (EC) groupreceived clonidine 2 µg kg^–1 in isotonic salinesolution 15 µg ml^–1. The extradural saline (ES)group received the equivalent volume of plain isotonic salinesolution. Pain was evaluated by a visual analogue scale (VAS)at 15-min intervals for the first 2 h and subsequently at 30-minintervals for the following 4 h. Morphine 5 mg was given s.c.when patients complained of pain after extradural saline orclonidine. In the EC group, the mean (SD) maximum pain reliefwas 68.2 (24.1)% of the initial VAS score, but it was only 14.7(25.2)% in the ES group. The mean duration of analgesia, beforeinjection of morphine, was significantly longer in the EC group(210 (87) min) compared with the ES group (45 (27) min) (P <0.001). Drowsiness and moderate hypotension were observed inthe EC group.     

Postural adjustment after an unexpected perturbation in children with haemophilia

Children with haemophilia often bleed inside joints and muscles, which may impair postural adjustments. These postural adjustments are necessary to control postural balance during daily activities. The inability to quickly recover postural balance could elevate the risk of bleeding. To determine whether children with haemophilia have impaired postural adjustment after an unexpected perturbation compared with healthy children. Twenty children with haemophilia comprised the haemophilic group (HG), and 20 healthy, age-paired children comprised the control group (CG). Subjects stood on a force plate, and 4% of the subjects' body weight was applied via a pulley system to a belt around the subjects' trunks. The centre of pressure (COP) displacement was measured after the weight was unexpectedly released to produce a controlled postural perturbation followed by postural adjustment to recover balance. The subjects' postural adjustments in eight subsequent intervals of 1 s (t1-t8), beginning with the moment of weight removal, were compared among intervals and between groups. The applied perturbation magnitudes were the same for both groups, and no difference was observed between the groups in t1. However, the COP displacement in t2 in the HG was significantly higher than in the CG. No differences were observed between the groups in the other intervals. Within-group analysis showed that the COP was higher in t2 than in t4 (P = 0.016), t5 (P = 0.001) and t8 (P = 0.050) in the HG. No differences were observed among intervals in the CG. Children with haemophilia demonstrated differences in postural adjustment while undergoing unexpected balance perturbations when compared with healthily children.     

Complete Atrioventricular Block As the First Manifestation of Noncompaction of the Ventricular Myocardium

Noncompaction of ventricular myocardium (NVM) is a rare cardiomyopathy, most probably caused by disturbances in embryonic morphogenesis of the myocytes, resulting in prominent trabeculations in the ventricular myocardium. Several diagnostic criteria have been proposed by echocardiography, and its association with other heart diseases is common. Its mortality is closely related to ventricular dysfunction, cardiac arrhythmias, and cardioembolic events. We report here a case of occurrence of atrioventricular block with syncope as the clinical manifestation of NVM. A brief review of the literature on morphological features, diagnosis, prognosis, and treatment will also be discussed.     

Electrode Polarity Is an Important Determinant of Defibrillation Efficacy Using a Nonthoracotomy System

Experimental and clinical data using epicardial patch electrodes and monophasic waveform suggest that electrode polarity may be an important determinant of defibrillation efficacy. Our objective was to examine the effect of electrode polarity in an animal model using a nonthoracotomy system and monophasic and biphasic waveforms for defibrillation. We examined the effect of lead polarity in 14 pentobarbital anesthetized dogs (21.1 ± 2.4 kg) using monophasic and biphasic shocks and a nonthoracotomy system. Monophasic and single capacitor biphasic shocks of 10-msec total duration were used. The lead system consisted of a right ventricular catheter electrode with 4-cm² surface area and a left chest wall subcutaneous patch electrode with 13.9-cm² surface area. Electrode polarities RV(?)-Patch(+) and RV(+)Patch(?) were tested using both monophasic and biphasic waveforms. Alternating current was used to induce ventricular fibrillation and test shocks were delivered after 10 seconds of ventricular fibrillation. Each polarity configuration for monophasic and biphasic waveforms was tested four times at five different capacitor voltage levels (200–600 V, in 100-V increments). Defibrillation efficacy curves were constructed using logistic regression analysis for each animal and energies associated with 80% probability of successful defibrillation (E80) were determined. The mean E80 ± SD values were as follows. Monophasic waveform: RV(?)Patch(+) 23.4 ± 7.5 J; RV(+)Patch(?) 20.9 ± 7.9 J(P <0.03). Biphasic waveform: RV(?)Patch(+) 15.8 ± 6.8 J; RV(+)Patch(?) 12.5 ± 6.0 J (P < 0.03). The mean impedance values for both waveforms using either polarity ranged from 65.4 to 67 ohms and were not significantly different. Biphasic waveforms were superior to monophasic (P < 0.01), regardless of lead polarity. For either waveform, reversal of lead polarity in some animals resulted in improved defibrillation efficacy and worsening in others, butasagroup, the RV(+)Patch(?) electrode configuration was superior. Conclusions: These observations suggest that electrode polarity is an important determinant of defibrillation efficacy for nonthoracotomy defibrillation. The optimal electrode configuration cannot be determined a priori, suggesting that alternate polarity configurations should be tested to maximize the defibrillation safety margin.