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Examining 18 patients without regurgitation (control group) and 20 patients with mitral regurgitation the method of Doppler echokardiography, the pulsating and continual wave, was applied. Both groups consisted of patients with heart diseases in whom a heart catheterization was indicated for the evaluation of the actual state. Thus, the competence of the mitral orifice was also evaluated. The aim of the investigation was to quantify or more accurately estimate the degree of mitral regurgitation. The accuracy of the Doppler method was tested by means of the measured cardiac stroke volumes of the right heart side in both groups with the probability higher than 80% but lower than 90% (0.80 less than p 0.23 less than 0.90), and by testing the cardiac stroke volumes of the right heart and the diastolic volumes of the left heart (control group: mitral and pulmonal orifice) with the probability higher than 70% and lower than 80% with the error of 6% of the measured volume. The regurgitation mitral fraction (RF) was presented as the difference between the total forwards volume (TFV) in the mitral orifice and the net forwards volume (NFV) in the pulmonal orifice and calculated in cm3, and as the regurgitation fraction index (RFI) in percentages (RFI = 1--NFV/TFV). It was also expressed as the regurgitation volume index (RVI) whose values were divided into degrees, according to the literature data. Numerical values of the regurgitation fraction and the regurgitation fraction index were classified in the mitral insufficiency degrees from 1 to 4. A fast regurgitation screening was possible due to the regurgitation fraction index, which is lower than the 45% of the diastolic volume in the cases of mild mitral insufficiency, while the values over 45% denote severe mitral insufficiency. The obtained values of the regurgitation fraction and index divided into degrees showed a close correlation with the angioventriculographic degrees obtained by heart catheterization. Cardiac output measured by the Doppler and Fick methods in the group with regurgitation showed a high correlation coefficient (r = 0.85) (0.60 less than p 0.47 less than 0.70).
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PMID:[Quantification of mitral regurgitation using Doppler echocardiography]. 235 94

The authors analyzed the left atrial (LA) time activity curve (TAC) in 18 normal subjects and 30 patients with mitral regurgitation (MR) to assess the usefulness of radionuclide ventriculography (RNV) in detecting MR. The LA TAC was generated from gated blood pool images using phase and amplitude images. The configuration of normal LA TAC was M shaped. The first peak and last peak of LA TAC were represented as points B and D, respectively. In addition, the trough following B was named point C. The presence and severity of MR was analyzed by use of three methods: (1) analysis of LA TAC, (2) analysis of left ventricular TAC, and (3) measurement of the stroke count ratio of left ventricle to right ventricle. In the diagnosis of MR using RNV, the rapid emptying fraction [REF:(B-C)/(B-A)] of LA TAC was the most sensitive index compared with the other two methods. The sensitivity and specificity of MR with Sellers' II degrees or more were 0.84 and 0.90 in LA TAC but were 0.42 and 0.90 in the count method.
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PMID:Assessment of mitral regurgitation using gated radionuclide ventriculography: analysis of left atrial time activity curve. 235 76

Recent studies have suggested that excision of the mitral valve apparatus during mitral valve replacement impairs left ventricular performance. However, functional measurements in humans have been difficult to obtain in a load-independent fashion. To investigate this concept, 12 patients (mean age, 65 +/- 8 years; mean New York Heart Association functional class, 3.3 +/- 0.7) with 4+ mitral regurgitation (n = 8) or mitral stenosis (valve area, 1.2 +/- 0.2 cm2) (n = 4) underwent prosthetic valve replacement using crystalloid cardioplegia. No patient required therapeutic inotropic support, every patient had at least the anterior mitral leaflet excised, and paced heart rate was maintained constant throughout. Left ventricular volume was measured with radionuclide angiocardiography, left ventricular pressure with a 3F micromanometer, and left ventricular wall volume with two-dimensional transesophageal echocardiography. Left ventricular preload was varied over a mean end-diastolic pressure range of 9 to 20 mm Hg and an end-diastolic volume range of 134 to 170 mL to generate four to five steady-state pressure-volume loops before and ten minutes after cardiopulmonary bypass. Left ventricular performance was estimated with the stroke work/end-diastolic volume relationship, which is insensitive to load. After bypass, no significant change (p greater than 0.1) was noted in wall volume for patients with mitral regurgitation or mitral stenosis (175 +/- 68 to 189 +/- 63 mL/m2 and 130 +/- 22 to 127 +/- 19 mL/m2, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effects of standard mitral valve replacement on left ventricular function. 236 81

We have used Doppler echocardiography to estimate the stroke volume (SV) in a study of 13 patients equipped with DDD pacemakers. SV was measured both during DDD and VVI pacing after observation times of 1,3,6, and 12 months of DDD pacing. SV was also measured at seven atrioventricular (AV) intervals (75-250 ms) in the search for optimal AV intervals. Mitral flow velocity was investigated to see if DDD pacing resulted in synchronous atrial contraction, and if mitral insufficiency existed at any of the pacing modes. Compared with the VVI mode, DDD pacing resulted in a mean increase in SV of 21 +/- 2% for the four observation periods. Two patients with severe left ventricular failure had no significant increase in SV during DDD vs VVI pacing. In each patient, an optimal AV interval ranging between 100-250 ms for the SV was found. Velocity profiles of mitral flow showed synchronous atrial contraction during DDD pacing, but not during VVI pacing. Mitral insufficiency was not seen in any pacing mode. DDD pacing resulted in a reduction in SV during the first 6 months, and was constant thereafter. Doppler echocardiography can be used repeatedly to evaluate the hemodynamic response of DDD pacing vs VVI pacing, and to find which AV interval gives the highest SV in the individual patient. Our study further shows that the hemodynamic benefit of DDD pacing is present after short-term as well as after long-term DDD pacing.
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PMID:A time-related study of the hemodynamic benefit of atrioventricular synchronous pacing evaluated by Doppler echocardiography. 241 37

The importance of the mitral complex in left ventricular contraction was studied in seventy-five patients who underwent mitral valve replacement (MVR) with preservation of the posterior mitral complex (modified MVR:mMVR), and in one hundred and twenty-two patients who had conventional mitral valve replacement (cMVR). Mechanical heart valves (Medtronic Hall or St. Jude Medical valves) were used in MVR. Patients after mMVR showed lower left atrial pressures, higher left ventricular stroke work indexes, and better left ventricular function curve using less catecholamines than those after cMVR during the initial 24 hours following cardiopulmonary bypass. M-mode echocardiographic analysis revealed that the sequential apex-to-base contraction of the ventricular wall was better preserved after mMVR than after cMVR. This tendency was more prominent in mitral regurgitation (MR) than in mitral stenosis (MS) patients. Echocardiographic analysis revealed that the posterior mid left ventricular segment began to contract and reached maximal contraction earlier than the basal segment in patients before and after mMVR. After cMVR, this tendency was less noticeable, and the contraction processed and peaked almost simultaneously in all segments. The mitral complex plays an important role in left ventricular contraction, and modified MVR can be said to be an excellent procedure for preserving left ventricular function.
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PMID:Importance of the mitral complex in left ventricular contraction--an analysis of the results of mitral valve replacement with preservation of the posterior mitral complex. 244 36

Cardiac performance and mitral regurgitation were measured by Doppler echocardiography and right heart catheterization in 12 patients with severe congestive heart failure who performed isometric exercise during control and intravenous administration of dobutamine and nitroglycerin. During control isometric exercise, mitral regurgitant volume increased from 18 +/- 13 to 31 +/- 17 ml (p less than 0.01), while forward stroke volume, by both thermodilution and Doppler echocardiography, substantially decreased. At rest, dobutamine decreased mitral regurgitant volume from 18 +/- 13 to 11 +/- 10 ml (p less than 0.05), while forward stroke volume increased from 46 +/- 13 to 55 +/- 15 ml (p less than 0.05). During isometric exercise, dobutamine tended to decrease mitral regurgitant volume (24 +/- 12 vs. 31 +/- 17 ml; NS) when compared with control exercise. At rest, nitroglycerin decreased mitral regurgitant volume from 18 +/- 13 to 11 +/- 11 ml (p less than 0.05), while forward stroke volume, by both thermodilution and Doppler echocardiography, substantially increased. Similarly, during isometric exercise, nitroglycerin decreased mitral regurgitant volume from 31 +/- 17 to 20 +/- 14 ml (p less than 0.05), while significantly increasing forward stroke volume. At control rest, the median mitral regurgitant fraction was 24% for the 12 patients. Neither dobutamine nor nitroglycerin changed significantly forward stroke and mitral regurgitant volumes at rest and during isometric exercise in the six patients with resting mitral regurgitant fraction below the median. In contrast, dobutamine and nitroglycerin significantly decreased mitral regurgitant volume and increased forward stroke volume both at rest and during isometric exercise in the six patients with mitral regurgitant fraction greater than the median.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Dynamic mitral regurgitation. An important determinant of the hemodynamic response to load alterations and inotropic therapy in severe heart failure. 250 26

To evaluate the short- and long-term effects of beta-adrenergic blockade (metoprolol) as well as the reaction to withdrawal and readministration of metoprolol in severe heart failure, 33 patients (25 men and eight women; mean age, 47.6 +/- 14.0 years) with dilated cardiomyopathy were studied by right and left heart catheterization, right ventricular biopsy, two-dimensional and Doppler echocardiography, and external pulse recordings. Twenty-six of 33 patients survived more than 6 months, and 24 of the 26 patients improved their functional class (from mean 3.3 to 1.8, p less than 0.0001). These 24 patients were subjected to withdrawal of metoprolol until the number of symptoms increased and deterioration occurred as observed noninvasively (group 1, n = 16), whereas the eight patients did not deteriorate during a 12-month period (group 2). During long-term treatment with metoprolol, there was an increase in ejection fraction from 0.24 to 0.42 (p less than 0.0001), whereas there was a decrease in the left ventricular (LV) end-diastolic dimension (from 7.3 to 6.4 cm, p less than 0.0001), in the grade of mitral regurgitation (from 1.7 to 0.4, p less than 0.0001), and in the grade of tricuspid regurgitation (from 0.6 to 0.05, p less than 0.007). There was a decrease in pulmonary wedge pressure (from 23.8 to 10.7 mm Hg, p less than 0.0001), LV end-diastolic pressure (from 24.1 to 13.4 mm Hg, p less than 0.002), and systolic vascular resistance (from 1,782 to 1,499 dynes/sec/cm, p less than 0.04). There was an increase in systolic blood pressure (from 116 to 132 mm Hg, p less than 0.003), cardiac index (from 2.17 to 2.58 l/min/m2, p less than 0.005), and LV stroke work index (from 31 to 65 g.m/m2, p less than 0.0001). During withdrawal of metoprolol, the heart rate and left atrial dimension increased (p less than 0.0001), whereas ejection fraction decreased (p less than 0.0001). The 12 (of 16) patients in group 1 who survived the withdrawal period had metoprolol readministered, and subsequently, ejection fraction increased (from 0.23 to 0.33, p less than 0.002). Patients had a low number of ventricular beta-adrenergic receptors compared with healthy control subjects (30.3 +/- 2.9 vs. 97.4 +/- 8.7 fmol/mg protein, p less than 0.001), but long-term treatment with metoprolol caused a moderate up-regulation (from 30.3 +/- 2.9 to 49.0 +/- 7.1 fmol/mg protein, p less than 0.05), which may facilitate a more normal response to sympathetic stimulation.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Long-term beta-blockade in dilated cardiomyopathy. Effects of short- and long-term metoprolol treatment followed by withdrawal and readministration of metoprolol. 234 91

The authors analyzed a group of 50 patients with an implanted artificial mitral valve. Group I consisted of 20 patients with an isolated left venous ostial stenosis. Group II consisted of 23 patients with a complex mitral disease, and group III--of 7 patients with mitral incompetence. Depending on the degree of improvement, the first two groups were divided into two subgroups: group Ia (13 patients) and group IIa (15 patients) with full clinical improvement, and group Ib (7 patients) and group IIb (8 patients) still requiring cardiological drugs and from time to time--dehydrating drugs. The observation time was from 1.5 to 4 years (on the average 39 months). In all the patients the artificial valve functioned properly. Before and after surgery the clinical state was evaluated according to NYHA, heart volume index (WOS), cardiopulmonary index (WSP) by a radiological examination, left-ventricular diastolic dimension (WRLK), left-ventricular systolic dimension (WSLK), left-ventricular end-diastolic volume index (WOKRLK), left-ventricular end-systolic volume index (WOKSLK), right-ventricular diastolic dimension (WRPK) and left atrium were evaluated by means of echocardiographic examination. Before surgery all the patients underwent the measurements of pressures in the pulmonary circulation, pulmonary resistance and heart index. The authors found a correlation between a degree of improvement after surgery and a functional group before surgery. Eleven patients from functional group III according to NYHA had been (before surgery) in a state of advanced circulatory failure (IV functional group). Clinical improvement was confirmed by statistically significant decrease in heart dimension evaluated by radiological and echocardiographic examinations. In group I left atrium dimension (LP) was significantly statistically larger in patients with incomplete clinical improvement. The authors also found a dependence of a distant result on a degree of hypertension in pulmonary artery, increased pulmonary resistance and decrease in stroke volume.
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PMID:[Late results of the treatment of mitral valve defects by implantation of an artificial heart valve]. 262 56

To evaluate the potential of magnetic resonance imaging (MRI) in detection and quantification of mitral regurgitation, 26 pts. with echocardiographically or angiographically documented mitral regurgitation were examined using a 0.5 Tesla superconducting magnet. In each patient a multislice-multiphase study in a sagittal-coronal double angulated projection (four-chamber view equivalent) was performed to assess left and right ventricular volumes, ejection fraction and regurgitant fraction. Additionally a blood flow sensitive cine-study (fast field echo: FFE) was done to visualize direction and area of regurgitant jet. MRI data were compared with quantitative and quantitative assessment of mitral regurgitation by angiography, 2D echocardiography, Doppler sonography and color flow mapping. Using the FFE mode MRI was able to detect the regurgitant jet as a typical signal loss within the left atrium in all patients. The ratio of regurgitant jet area/left atrium area as determined by MRI showed a correlation with a comparable ratio from color Doppler sonography of R = 0.87 (p less than 0.001). There was also good agreement in semiquantitative grading of mitral regurgitation between MRI and angiography (R = 0.77, p less than 0.001). The determination of left and right ventricular stroke volume allowed the calculation of the regurgitant fraction, which showed a correlation with invasively determined regurgitation fraction of R = 0.84 (p less than 0.001). These data provide additional information that MRI may be useful as a noninvasive technique to detect and quantify mitral regurgitation.
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PMID:Assessment of mitral regurgitation by magnetic resonance imaging. 263 Aug 43

This study was undertaken to determine whether rigid-ring annuloplasty and flexible-ring annuloplasty have the same effect on left ventricular function in patients with chronic mitral regurgitation secondary to degenerative disease of the mitral valve. Twenty-five patients who underwent isolated mitral valve repair and required annuloplasty were randomized into two groups: rigid-ring and flexible-ring annuloplasty. Left ventricular function was assessed by echocardiography and radionuclide angiography on the day before operation and 2 to 3 months later. Preoperative left ventricular function was similar in the two groups of patients. Postoperatively, left ventricular end-diastolic diameter and volume decreased significantly in both groups. The left ventricular end-systolic diameter and volume decreased significantly only in patients with a flexible annuloplasty ring. Left ventricular systolic function as assessed by pressure-volume relationships was significantly better in patients with a flexible ring (p less than 0.02 by analysis of covariance), and left ventricular performance measured by stroke volume-end-diastolic volume relationships was also better in these patients (p less than 0.05 by analysis of covariance). These data indicate that patients with a flexible annuloplasty ring have better left ventricular systolic function than patients with a rigid annuloplasty ring 2 to 3 months after mitral valve reconstruction for chronic mitral regurgitation secondary to degenerative disease of the mitral valve.
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PMID:Mitral valve annuloplasty: the effect of the type on left ventricular function. 231 Feb 67


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