John W. Allen

Percutaneous double balloon valvotomy for severe rheumatic mitral stenosis

Percutaneous double balloon valvotomy for severe rheumatic mitral stenosis was successfully performed in 281 of 285 consecutive patients. The changes evoked were a decrease of the mean transvalvular gradient from 16 +/- 7 to 5 +/- 3 mm Hg, an increase in cardiac output from 3.8 +/- 1.0 liters/min to 5.4 +/- 1.5 liters/min and an increase in mitral valve area from 0.86 +/- 0.24 cm2 to 2.41 +/- 0.54 cm2. The mean pulmonary artery pressure decreased from 37 +/- 13 mm Hg to 27 +/- 12 mm Hg and the pulmonary vascular resistance decreased from 307 +/- 181 to 238 +/- 122 dynes/s/cm-5. Symptomatic improvement occurred in 272 of the 285 (95%) patients. There were 3 procedure-related deaths (1%). Postdilatation mitral regurgitation was not significant in most patients. Therefore, this procedure can be performed at a low risk with effective results and a fast recovery.

Mitral E point septal separation: A reliable index of left ventricular performance in coronary artery disease

The diagnostic value of E point septal separation (EPSS) was assessed in 108 patients with coronary artery disease who underwent coronary angiography and M-mode echocardiography within a 2-year period at LAC/USC Medical Center. In patients with anterior myocardial infarction, EPSS correlated well with angiographic ejection fraction, with a specificity of 85% and sensitivity of 82%. In inferior myocardial infarction, a 21% frequency of falsely elevated EPSS values was encountered; the sensitivity for detecting reduced ejection fraction was 100% and the specificity was 67%. In combined anterior and inferior myocardial infarction, EPSS accurately estimated abnormal ejection fractions with a sensitivity and specificity of 100%. An abnormal EPSS (more than 7 mm) was found to be more sensitive (87%) and specific (75%) in detecting individuals with angiographically reduced ejection fraction (less than 50%) compared to other echocardiographic indices of pump function. Importantly, EPSS was effective in estimating left ventricular function in the presence of left bundle branch block, paradoxical septal motion, and angiographic septal, posterior, and anterior wall motion abnormalities.

Problems in ultrasonic estimates of septal thickness

Problems related to cardiac anatomy and ultrasonic instrumentation affect the accuracy of echographic identification of endocardial echoes. A cadaver model and 13 patients were studied, with direct identification or with the aid of echographic contrast techniques, to identify accurately the endocardial echo. The study showed that (1) echographic contrast agents delineate an endocardial echo in the central portion of the ultransonic beam; (2) a specular reflector exists within the right ventricular cavity; (3) specular reflectors within the septum may give the false appearance of border-forming echoes; (4) septal thickness varies by 1 to 5 mm after the endocardial echo has been identified by the contrast agent; and (5) spurious echoes, related to a wide beam angle, can be confused with the endocardial echo. In light of these problems, three criteria were utilized for endocardial echo identification: the prominent notch in the left septal echo, the specular quality of the right septal echo, and the association of multiple myocardial echoes moving in parallel. With these criteria, the endocardial echoes in 11 of the 13 patients could be accurately identified without the use of a contrast agent. The identification of these problems should provide helpful guidelines in developing more accurate and reproducible criteria for septal thickness measurements.

Musical murmurs: an echo-phonocardiographic study.

Five patients with muscial murmurs were studied noninvasively with simultaneous echocardiography and phonocardiograpy and phonocardiography. Three patients had aortic regurgitation, one mitral regurgitation and one tricuspid regurgitation. The frequency of the muscial murmurs ranged from 40 to 158 cycles/sec. The patient with tricuspid regurgitation manifested an inspiratory honk. Simultaneous echo-phonocardiography revealed regular valve leaflet flutter (aortic, mitral or tricuspid) at a frequency identical to that of the simultaneously recorded muscial murmur. This study demonstrates that echocardiography is a useful noninvasive tool in identifying the site of origin of musical murmurs.

Double opening sound related to dysfunction in a caged disc mitral valve prosthesis

Abstract A grooved embolic fragment was removed from the femoral artery of a patient with a Kay-Shiley caged disc mitral valve prosthesis. An extra opening click that had been present before embolization disappeared coincidentally. This study demonstrates (1) the importance of establishing an expected range of normal systolic time intervals for a given prosthetic heart valve configuration, (2) the value of postoperative phonocardiograms in documenting the presence of an unexpected extra sound, and (3) the need for careful examination of embolic fragments recovered from patients with valve prostheses.

The role of serial echocardiography in the evaluation and differential diagnosis of pericardial disease

Echocardiography is an established method for the diagnosis of pericardial effusion. Echographic findings in fibroadhesive disease have also been described. The interpretation of a changing serial echogram during the clinical course of pericardial disease has not been established. Sixteen patients with echographic evidence of pericardial effusion were followed with serial echographic studies. In seven, surgical or autopsy correlation was obtained. Because of the serial changes noted we undertook a study in dogs to clarify the problem of variability in intensity of sound reflected from the pericardial space. Three open-chested dogs were studied with rapid sequence surface echograms as blood introduced into the pericardial space was converted from the unclotted to the clotted state. In all three dogs blood clooting increased the intensity or sound reflected from the pericardial space. Our study of two patients with fibroadhesive pericardial disease documents serial changes in echoes from the pericardium and pericardial space accompanying the clinical evolution of the disease process, and suggests a method for avoiding the commonly encountered difficulty in proper identification of the pericardial and epicardial echoes. Our preliminary studies suggest that serial echograms should play an important role in the management of patients with pericardial effusion; further surgical/pathological correlations are required.

R-pulse wave timing: A technique for continuous cardiovascular monitoring in obstetrics—Preliminary report

A simple, noninvasive technique for continuous cardiovascular monitoring in obstetrics using R--pulse wave timing is described. This preliminary study suggests that different maternal heart rate/R pulse patterns are found in different clinical circumstances. A significant decrease in the R pulse interval occurred in the third trimester in both normal and diabetic women in the left lateral position when compared to the supine position. The R pulse intervals were all prolonged in the standing position in both gravid and nongravid women. During labor R pulse interval usually shortened during uterine contraction. Prolongation of R pulse interval was observed during thiopental injection, hypotension, and excessive bleeding at cesarean section. Exercise testing in healthy male subjects suggested that the change in R pulse interval becomes constant when the oxygen consumption rate reaches a plateau at 100% maximal work load. Further extensive clinical study appears worthwhile since it may add another dimension to cardiovascular monitoring and give an early indication of cardiovascular reserve.

Effects of atenolol on left ventricular hypertrophy and early left ventricular function in essential hypertension

Echocardiographic studies of left ventricular (LV) hypertrophy indicate clinical benefits of antihypertensive therapy. Therefore, M-mode and Doppler techniques were used to assess changes in LV hypertrophy after 10, 30 and 50 weeks of atenolol therapy (50 or 100 mg once daily) in 19 patients with essential hypertension. After 50 weeks of atenolol treatment, the most notable changes were: for M-mode parameters, increases (p less than 0.05) in diastolic LV internal dimension, radius to thickness ratio and stroke volume, and decreases (p less than 0.01) in total wall thickness and heart rate; for Doppler parameters, increases (p less than 0.01) in slope and peripheral resistance, and decreases (p less than 0.01) in heart rate, stroke volume and cardiac output. The decreased total wall thickness and increased radius to thickness ratio suggest a trend toward regression of LV hypertrophy. These findings, along with improvements in blood pressure, pulse and exercise stress tests, indicate potential benefits of atenolol in managing patients with essential hypertension and LV hypertrophy.

Clinical data versus noninvasive testing as an estimate of coronary status

The step from coronary angiography to surgery is taken primarily on the basis of the ejection fraction (EF) and number of diseased vessels (NV), taken jointly as coronary status (CS). This study reviewed (1) how well EF, NV and CS are estimated from clinical data, (2) how much improvement is gained by adding noninvasive data, (3) how good this model is when applied to a larger cohort and (4) whether the decision to angiography can be made on the basis of CS estimated from clinical data alone. A quantitative definition of CS was established as a principal component of EF and NV. Estimates of EF, NV and CS were made from clinical data of 60 patients. Correlations with the actual values were EF 87%, NV 93% and CS 93%. When noninvasive data were added to this model, the correlations increased to EF 95%, NV 99% and CS 98%. When the clinical data model was applied to 169 patients, the correlations decreased to EF 77%, NV 71% and CS 74%. CS estimated from clinical data alone was set up as a test for angiography for 169 patients. This test had a sensitivity of 98% and a specificity of 63%, demonstrating the feasibility of using clinical data alone in deciding angiography.