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D T Anbe

Publications and source records attributed to D T Anbe.

12 recordsLinked to original sources
PubMed1979

Performance of the failing and nonfailing right ventricle of patients with pulmonary hypertension.

Hemodynamic performance of the right ventricle was measured in 34 patients: 17 with pulmonary hypertension, 9 with pulmonary hypertension and right ventricular failure and 8 control subjects. Among the patients with pulmonary hypertension who did not have right ventricular failure, right ventricular maximal isovolumic rate of development of ventricular pressure (dP/dt) was significantly elevated (P less than 0.001), whereas maximal 1/P dP/dt and maximal velocity of contractile element shortening (Vmax) were comparable with values observed in control subjects. The patients with pulmonary hypertension who had right ventricular failure also showed an augmented right ventricular maximal dP/dt (P less than 0.001) and normal 1/P dP/dt and Vmax. These observations indicate that in pulmonary hypertensive heart disease, even when the right ventricle failed in a clinical sense, the contractile effort was normal. Consequently, right ventricular failure may develop in patients with pulmonary hypertensive heart disease even though the cardiac muscle performs normally as a contractile tissue.

Cardiac Output↗
PubMed1979

Diagnostic value of visualization of the right ventricle using thallium-201 myocardial imaging.

The diagnostic significance of visualizing the right ventricle on thallium-201 myocardial perfusion scans (T-scan) at rest was studied in 53 patients. In 33 patients the right ventricle was visualized clearly on the T-scan (group A). Hemodynamic evidence of right ventricular hypertension with systolic pressure greater than or equal to 30 mmHg was present in 28 of 33 (85%) of these patients. Right ventricular volume overload with left-to-right shunt greater than 2:1 was present in three patients. Other tests were diagnostic for right ventricular enlargement and or pulmonary hypertension as follows: chest x-ray (58%), echocardiogram (36%) and electrocardiogram (15%). In an unselected group of 20 patients (group B) where resting T-scan did not show visualization of the right ventricle, the right ventricular systolic pressure was less than 30 mm Hg in all. The other noninvasive tests did not reveal presence of right ventricular hypertrophy or enlargement. T-scan appears to be a useful and sensitive test in detecting right ventricular pressure or volume overload compared with other noninvasive tests. This may be useful in detection of patients with right ventricular hypertrophy or enlargement secondary to pulmonary hypertension or other causes.

Adult↗
PubMed1979

Intracardiac sound as a diagnostic adjunct in subaortic stenosis.

The purpose of this investigation is to demonstrate the potential diagnostic value of intracardiac sound recordings in patients with subaortic stenosis. Intracardiac pressure and sound were measured in 10 patients with various types of subaortic obstructions using a catheter-tip micromanometer. Seven patients had idiopathic hypertrophic subaortic stenosis (IHSS), 2 had a subvalvular membrane, and 1 had a subvalvular tunnel. Within the left ventricular cavity, at the site of maximal systolic left ventricular pressure, either there was no systolic murmur, or the murmur was of low intensity. However, within the outflow tract of the left ventricle, distal to the site of intraventricular obstruction, a prominent systolic murmur was detected in all patients. This murmur was of higher intensity than the one measured distal to the aortic valve. In one patient, in whom no subvalvular obstruction was present, but in whom entrapment of the tip of the catheter occurred, no murmur was detected in the left ventricle even though a subvalvular pressure gradient was observed. Therefore it appears that a systolic murmur recorded with maximal intensity in the outflow tract of the left ventricle may be of substantial help in distinguishing between an artifactual intraventricular pressure gradient, and one that results from intraventricular obstruction.

Aortic Stenosis, Subvalvular↗
PubMed1978

Significance of momentary pressure changes during isovolumic relaxation.

Sudden momentary fluctuations of left ventricular, aortic, right ventricular, and pulmonary arterial pressure were noted during isovolumic relaxation of the respective ventricles. The presence of such transients raised questions related to their meaning and significance. The purpose of this report is to emphasize the nonartifactural nature of these pressure transients and to describe their origin and significance in the cardiac cycle. Pressure transients were observed in 31 of 32 patients with normal aortic valves, and in 17 patients with normal pulmonary valves in whom right-sided measurements were made. Such transients, however, were absent on the left ventricular and aortic pressure recordings of three patients with calcific aortic stenosis. These sudden changes in pressure are indicative of momentary compressions and rarefactions of the blood that occur within the ventricles and their respective arterial chambers. Whenever present, pressure transients were noted to occur coincident with the major aortic or pulmonary components of the second sound. Since intraaterial sound pressure is derived from the pressure signal by litering the low frequencies and amplifying the high frequencies, one can deduce that intraarterial sound pressure is in fact a representation of these pressure changes. The recognition of these pressure transients on an otherwise smooth ventricular, aortic, or pulmonary arterial pressure places in proper perspective their role in the production of the second heart sound.

Aorta↗
PubMed1978

Exploration of the cause of the low intensity aortic component of the second sound in nonhypotensive patients with poor ventricular performance.

This investigation was undertaken to explore the cause of the diminished second sound (S2) that may occur in normotensive patients with poorly performing ventricles. Intra-aortic sound and pressure were measured in 16 patients with angina; eight had normal ventricular performance (ejection fraction greater than or equal to 60%) and eight had poor performance (ejection fraction less than 50%). The amplitude of S2 was lower in patients with poor ventricular performance as was negative d/dt. Aortic pressure was conparable in both groups. The ampitude of S2 was linearly related to the rate of change of the pressure gradient that developed across the aortic valve during diastole (r = 0.82). The latter also correlated with negative dp/dt (r = 0.82). These observations indicate that in patients with poor ventricular performance, isovolumic relaxation may be compromised. This would cause a reduction of the rate of development of the diastolic pressure gradient, which would result in a diminished S2.

Adult↗
PubMed1977

The aortic closure sound in pure aortic insufficiency.

The second sound in aortic insufficiency has been described as accentuated, normal, or moderately diminished. A study of intracardiac phonocardiograms was performed to evaluate its intensity and to eliminate extracardiac factors. Pressure and intracardiac sound measurements were made in 28 patients undergoing diagnostic cardiac catheterization. Recordings were obtained above the aortic valve and within the left ventricle in 14 patients with normal aortic valves and 11 patients with aortic insufficiency uncomplicated by aortic stenosis. The amplitude of the aortic closure sound in the patients with pure aortic insufficiency, 1000 +/- 100 dynes/cm2, was significantly lower than in those patients with normal aortic valves, 3100 +/- 200 dynes/cm2 (P less than 0.001). The results indicate, therefore, that the presence of aortic insufficiency causes a diminished amplitude of the aortic closure sound. These results are supportive of the theory that the second heart sound is caused by diastolic vibrations of the closed aortic cusps. Diminished valvular vibrations and sound would occur in pure aortic insufficiency if the valve is unable to properly tense during diastole, or if the rate of development of the driving pressure is diminished.

Aortic Valve↗
PubMed1975

Spontaneous closure of paravalvular leak after mitral valve replacement.

Complications after prosthetic valve replacement may be multiple. In biologic valves, valve detachment and cusp perforation may occur. If this is of significant magnitude, reoperation may be required. This report describes recurrent mitral regurgitation after mitral valve replacement with a Hancock porcine xenograft. The regurgitation subsided spontaneously three months later. We felt that a paravalvular leak closed, with progressive fibrosis and tightening of the annulus. Functional results in this patient were excellent.

Adult↗
PubMedDate not supplied

Delayed conversion to sinus rhythm after direct-current countershock.

Elective cardioversion for supraventricular arrhythmias has been performed in 203 patients during a 30-month period beginning in May, 1972. In five instances conversion to normal sinus rhythm occurred well after the electric shock had been delivered. The interval ranged from 4 to 105 seconds after DC countershock. In one patient, atrial fibrillation clearly persisted for eight seconds after DC countershock, however, immediately after countershock the ventricular rate became regular and, in addition to the fibrillatory activity, apparent sinus P-waves became visible and the same regular rate persisted after disappearance of fibrillatory waves. This raised the possibility of atrial dissociation. Our experience suggests that if apparent failure of conversion is noted after DC countershock, a repeat shock at a higher level should not be administered immediately but only after observing the rhythm for up to two minutes. Other possible mechanisms of delayed conversion are discussed.

Adult↗