Left ventricular 'relative wall thickness', determinedfrom the ratio between echocardiographic measurements of end-systolic wall thickness and cavity transverse dimension, was related to peak systolic intraventricular pressure in I5 normal subjects, in I5 patients with left ventricular volume or pressure overload without aortic stenosis, and in 23 patients with aortic stenosis. All these patients had a mean rate of circumferential fibre shortening greater than I.O circumference per second and were regarded as having good ventricular function. Relative wall thickness was found to be normal in cases of volume overload and to be increased in pressure overload, being proportional to the systolic intraventricular pressure. Values for the ratio of systolic intraventricular pressure to relative wall thickness in the normal subjects and patients without aortic stenosis were similar (mean 30+ 2.5). Based on this relation, estimates ofpeak systolic intraventricular pressure were made in the cases of aortic stenosis using theformula: systolic intraventricular pressure (kPa) = 30 x wall thickness . transverse dimension. Peak systolic aortic valve gradients derived by subtracting brachial artery systolic pressure, measured by sphygmomanometer, from the echocardiographic estimates of intraventricular pressure comparedfavourably with the gradients measured at left heart catheterization (r=o.87, P< o.OOi).Aortic valve orifice areas, derived from echocardiographic estimates of stroke volume, ejection time, and valve gradient, rangedfrom 0.21 to 3.16 cm2 and appeared to correlate with the severity of aortic stenosis. All patients with aortic stenosis, with or without coexistent mild aortic regurgitation, who were recommended for aortic valve surgery, had estimated valve orifice areas of less than o.8 cm2.A further io patients with pressure or volume overload had mean rates of circumferentialfibre shortening of less than I.o circumference per second and were regarded as having poor ventricular function. In these cases values for relative wall thickness were lower than in those with good ventricular function and were not proportional to systolic intraventricular pressure.In patients with good left ventricular function systolic intraventricular pressure is proportional to, and can be estimatedfrom, echocardiographic measurement of relative wall thickness.

Summary:Two cases are reported in which amiodarone was administered during pregnancy for longer periods than has been reported previously. Limited placental transfer of amiodarone and its desethyl metabolite was observed in both cases. A normal child resulted from each pregnancy despite, in one case, amiodarone therapy throughout the entire pregnancy. However, caution is urged in the use of amiodarone during pregnancy in view of the limited data available.

SummaryFifty-nine (42 %) of 140 schizophrenic patients taking phenothiazines were found to have abnormal electrocardiograms. The abnormalities included T wave changes, S-T depression, P-R and Q-T prolongation, persistent sinus tachycardia (110 or more/min) and right bundle branch block.In forty-eight (34%) of the fifty-nine patients, the ECG abnormalities disappeared after stopping the phenothiazine and reappeared on its resumption. IntroductionElectrocardiographic abnormalities and sudden death have been reported in patients taking phenothiazines and closely related compounds such as imipramine and amitriptyline (Kelly, Fay and Laverty, 1963;Alexander and Nino, 1969). This paper records the incidence of ECG abnormalities in a large population of schizophrenic patients taking phenothiazine -chiefly chlorpromazine, thioridazine, fluphenazine and trifluoperazine-and provides new evidence of the effects of exercise on these changes.

Echocardiography detected asymmetric septal hypertrophy (ASH) in five of 200 adults being assessed for aortic valve surgery. Four of these were among 119 patients with dominant aortic stenosis, which was severe in three. ASH was confirmed at the time of aortic valve replacement in two of these patients; the third declined operation.The finding of ASH in only one of 81 patients with free aortic reflux is consistent with chance association. While the same explanation could apply to the higher prevalence in those with aortic stenosis, it may be that a long-standing pressure overload can trigger inappropriate septal hypertrophy in predisposed individuals.Brock (1957)

The mitral valve was assessed by echocardiography in 20 patients, aged 27 to 67 years, who subsequently underwent mitral valve replacement. After removal, the mitral valve cusps were examined by direct measurement, radiography, and quantitative calcium extraction. Increased thickness of the E-F echo was found where calcification or fibrosis was present, differentiation by echocardiography alone being unreliable. However, multiple dense parallel E-F echoes were found in all 10 patients with more than 80 milligrammes of calcium in the valve, while a single thin E-F echo indicated the absence of significant calcification or fibrosis. This study was undertaken primarily to test the middle of its free edge. The degree of any fibrosis clinical impression that dense E-F echoes denote present was scored 1 to 3. calcification of the mitral leaflets. The basis of the The valve was then placed in calcium-free fixative study was the comparison of preoperative echo-and suspended in a known volume of Custer's decalcicardiographic measurements with the operative fying fluid for 72 to 96 hours. The amount of calcium findings and with the pathological findings in the extracted was estimated by fluorimetry. inndigs and with the pathological findigs i the Correlation between the in vivo and in vitro data was removed valves, but correlation with the fluoro-sought, using standard statistical methods. scopic appearances was also sought.