Biomedical subjects

U Nellessen

Publications and source records attributed to U Nellessen.

At least 37 records · Page 2Linked to original sources

PubMed1992

[An aortopulmonary shunt after a knife wound].

An extensive hemopneumothorax developed in a 23-year-old man after having been knifed in the region of the left nipple. After general surgical care a Bülau suction drain was inserted. Cardiological examination became necessary a week later when a chest X-ray film demonstrated an enlarged cardiac silhouette. Echocardiography revealed pericardial effusion (about 600 ml) which was removed by pericardial aspiration. Cross-sectional and colour Doppler echocardiography showed a shunt between the aorta and right ventricular outflow tract at the origin of the pulmonary artery. At surgery a fistula between the root of the aorta and the pulmonary artery was identified (the posterior sinus near the anulus was nearly completely detached). The fistula was closed and the pulmonary valve reconstructed. The early and late postoperative course was unremarkable.

Adult↗

PubMed1992

Performance of a stentless xenograft aortic bioprosthesis up to four years after implantation.

Conventional biologic and mechanical prostheses have important limitations with regard to their hemodynamic characteristics and long-term durability. We evaluated the hemodynamic function of a stentless porcine aortic prosthesis in 10 patients by invasive pressure measurements and angiography with videodensitometry 8 +/- 4 days after operation, as well as by Doppler echocardiography 35 +/- 15 months after valve replacement. The early postoperative invasive study revealed a mean gradient of 8 +/- 6 mm Hg across the prosthesis, no regurgitation in eight patients, and mild regurgitation, defined as less than 20% regurgitant fraction, in the remaining two patients. The late postoperative Doppler echocardiographic study revealed a mean gradient across the aortic prosthesis of 6 +/- 3 mm Hg, mean Doppler-derived valve orifice area of 1.8 +/- 0.6 cm2, and color Doppler flow velocity mapping suggested no regurgitation in eight patients and mild regurgitation in two patients corresponding to early postoperative angiography. None of the 10 patients received anticoagulation therapy. The clinical course of all patients was without incident. This stentless aortic bioprosthesis may offer hemodynamic advantage; however, further studies are needed to allow comparison with conventional mechanical and biologic prostheses.

Adult↗

PubMed1991

Unstented and partial stented bioprostheses for aortic valve replacement--up to 6 years of follow-up.

Since January 8, 1985, three different designs of unstented (type A, n = 9) and partial stented (type B, n = 4; and type C, n = 3) glutaraldehyde preserved porcine aortic valves were used for aortic valve replacement in 16 patients with acquired aortic valve lesions. Type A and type B prostheses were implanted using a two suture row technique. In type C prostheses, only a single suture row was necessary for implantation, facilitating surgery considerably. In all patients, the fully flexible commissures of the bioprostheses were secured to the aortic wall of the recipient. There was no hospital mortality. Two patients with type A bioprostheses died due to noncardiac causes, 4 and 24 months postoperatively. One bioprosthesis in this group had to be replaced after 3 months because of insufficiency. Serial Doppler echocardiographic studies were performed up to 6 years after implantation. No significant leaflet calcification was observed. In three type A bioprostheses, a mild insufficiency without progression was recorded. The latest mean/peak transprosthetic pressure gradients were: type A: 6 +/- 4 mmHg/12 +/- 6 mmHg; type B: 6 +/- 3 mmHg/14 +/- 5 mmHg; and type C: 11 +/- 5 mmHg/18 +/- 8 mmHg. The functional results of the type A and type B bioprostheses have proven to be satisfactory. The slightly higher pressure gradients in patients with a type C bioprosthesis give rise to further refinements of its design. These results confirm the usefulness of imitating normal anatomy by using unstented or partial stented bioprostheses.

Adult↗

PubMed1991

[Flexible aortic valve prostheses: long-term functional results with porcine bioprostheses without mechanical commissure stent and aortic homografts].

The long-term performance of two different types of flexible aortic prostheses was evaluated in 10 patients who received a stentless porcine prosthetic valve (group A) and in 18 patients who underwent aortic valve replacement with an aortic homograft (group B). In group A early postoperative angiography (5-16 days post surgery) revealed a mean gradient across the aortic prosthesis of 8 +/- 6 mmHg. Late postoperative Doppler echocardiography (3.2 +/- 0.9 years post surgery) suggested a mean gradient of 6 +/- 3 mmHg with a Doppler derived valve orifice area of 1.8 +/- 0.6 cm2. Color Doppler visualized mild prosthesis regurgitation in two of the 10 patients and two-dimensional imaging showed no significant leaflet calcification. In group B late postoperative Doppler echography (5.2 +/- 1.6 years post surgery) suggested a mean gradient of 11 +/- 14 mmHg with a mean graft orifice area of 1.8 +/- 0.5 cm2. Color Doppler revealed prosthesis regurgitation in 15 patients (severe 1, moderate 2, mild 12) and two-dimensional imaging visualized significant prosthesis leaflet calcification in two patients. The good hemodynamic function of a stentless porcine bioprosthesis which seems to be preserved for at least several years indicates that the use of the flexible aortic xenograft is worthwhile pursuing. The long-term performance of an aortic homograft is relatively poor and may be due to unsolved problems with regard to sterilizing and storing the valves.

Adult↗

PubMed1991

[Young patient with left brain infarct and transient right sided hemiparesis in cardiac papillary fibroelastoma].

This is a case report of a 25-year-old female with recurrent episodes of transient cerebral ischemia accompanied by transient hemiparesis. Cardiac ultrasound examination revealed a small left-ventricular tumor located between the chordae tendineae. The echocardiographic finding was subsequently confirmed by surgery. The entire tumor was removed and the mitral valve remained intact. Due to the histological and immunohistochemical findings a papillary fibroelastoma was diagnosed. The early and late postoperative course was without event.

Adult↗

PubMed1990

Features of the angiographic evaluation of the INTACT study. International Nifedipine Trial on Antiatherosclerotic Therapy.

INTACT (International Nifedipine Trial on Antiatherosclerotic Therapy) is a prospective, placebo-controlled, randomized, double-blind, multicenter trial analyzing the influence of 80 mg nifedipine/day on the angiographic progression of early stage coronary atherosclerosis. Coronary angiograms were taken in identical projections before and after a treatment period of 3 years. Quantitative analysis of the angiograms was performed with the computer-assisted contour detection system CAAS. For definition purposes, the coronary artery system was subdivided into 25 different segments, including all anatomic variants. Measurement parameters of segments were mean and minimal diameter, and of stenoses minimal diameter, percentage diameter reduction (at least 20%), length, and plaque area. The variable extent of the changes of these parameters in the different projections analyzed per patient in the two study angiograms was considered by separate computation of the maximal, mean, and minimal changes over these projections; the comparison of the parameter changes between the two treatment groups was performed separately according to these three modes. For all parameters, this comparison was performed on the basis of the individual 25 segments, as well as after aggregation of individual segments to arteries (RCA, LAD, and LCX), to groups of large and small segments, and to the entire coronary artery system. Assessment of changes of the coronary (patho)morphology by quantitative analysis of coronary angiograms is associated with a number of methodical limitations, which may lead to a certain variability of the results. However, due to the double-blind feature of INTACT, this variability should be comparable in the two groups of this study, allowing for a conclusive comparison.

Angiography↗

PubMed1990

[Diagnosis of ventricular septum rupture following acute myocardial infarct using a fiber-optic indwelling catheter].

Rupture of the ventricular septum is a rare complication of acute myocardial infarction. Time of diagnosis, hemodynamic condition, as well as duration and effectiveness of the preoperative treatment determine the clinical outcome after surgical repair. Since its introduction the bedside-applied Swan-Ganz catheter has maintained an important role for the rapid confirmation and quantitation of the infarct-induced ventricular septal rupture. We report on the clinical courses of two patients whose diagnoses were established by means of a fiberoptic-armed Swan-Ganz catheter. Accuracy of the measured oxygen saturation was controlled by in vitro gas analyses with heparinized blood samples. As compared to conventional methods the continuous in vivo oximetry by a fiber-optic system is a simple procedure which facilitates repeated shunt calculations during hemodynamic monitoring in critically ill patients.

Catheterization, Swan-Ganz↗

PubMed1989

Ultrasonic tissue characterization with a real time integrated backscatter imaging system in normal and aging human hearts.

Experimental studies have shown that variation in the magnitude of integrated ultrasonic backscatter during the cardiac cycle represents acoustic properties of myocardium that are affected by pathologic processes; however, there are few clinical studies using integrated backscatter. Forty subjects without cardiovascular disease (aged 22 to 71 years, mean 41) were studied with use of a new M-mode format integrated backscatter imaging system to characterize the range of cyclic variation of integrated backscatter in normal subjects. Cyclic variation in integrated backscatter was noted in both the septum and the posterior wall in all subjects. The magnitude of the cyclic variation of integrated backscatter and the interval from the onset of the QRS wave of the electrocardiogram to the minimal integrated backscatter value were measured using an area of interest of variable size for integrated backscatter sampling and a software resident in the ultrasound scanner. The magnitude of cyclic variation was larger for the posterior wall than for the septum (6.3 +/- 0.8 versus 4.9 +/- 1.3 dB, p less than 0.01). The interval to the minimal integrated backscatter value was 328 +/- 58 ms for the septum and 348 +/- 42 ms for the posterior wall (p = NS). There was a weak correlation between the magnitude of cyclic variation of integrated backscatter and subject age for the posterior wall (r = -0.47, p less than 0.01), but this was not significant for the septum (r = -0.21) (partially because of inability to exclude specular septal echoes) and septal endocardium.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1989

Coronary vasodilation with dihydropyridines--a pharmacokinetic study.

In 26 patients with coronary artery disease, the mean diameters of angiographically 'normal' epicardial coronary arteries were assessed with the aid of a computer-assisted contour detection system (CAAS) before and up to 15 min after onset of a 4-min intravenous-infusion of 2 mg nifedipine (13 patients, group I) or 1 mg nisoldipine (13 patients, group II). Maximal coronary dilation amounted to 20 +/- 9% (4th min) in group I and to 18 +/- 9% (15th min) in group II. In addition, in group II changes of the minimal diameters of 9 coronary obstructions were measured; the maximum increase averaged 28 +/- 15% (7th min). In order to compare the pharmacokinetic properties of these compounds the dilation of the 'normal' coronary segments was correlated with the respective drug plasma levels; maximal plasma concentrations averaged 62 +/- 21 ng ml-1 (7th min) in group I and 17 +/- 7 ng ml-1 (4th min) in group II respectively. A positive, linear correlation between coronary dilation and plasma levels was only found with nifedipine (P less than 0.05); with nisoldipine, however, coronary dilation developed in form of a hysteresis curve, when plotted against plasma levels, probably due to the high receptor affinity of this substance. The prolonged efficacy of nisoldipine could be favourable in oral long-term treatment of patients with coronary artery disease.

Adult↗

PubMed1989

Influence of ionic and non-ionic radiographic contrast media on the vasomotor tone of epicardial coronary arteries.

The effect of ionic and non-ionic contrast media on the vasomotility of epicardial coronary arteries was investigated in 21 patients during coronary angiography by use of either diatrizoate-76% (10 patients, group A) or iopromide-370 (11 patients, group B). Coronary angiograms were taken in RAO 30 degrees projection before (= reference) and directly after (t0) diagnostic angiography of the left coronary artery (approx. 7 dye injections in approx. 7 min). Additional angiograms in the same projection followed after 1, 3, 6 and 10 min. Mean diameters of angiographically normal coronary segments were analysed with an automatic edge detection system (CAAS). With diatrizoate-76% coronary dilation at t0 averaged 18.9 +/- 6.7% (P less than 0.001); it correlated positively (P less than 0.001) with the number of diagnostic injections performed per min (mean 1.2 +/- 0.3 min-1), and negatively (P less than 0.5) with the time interval between the last diagnostic contrast injection and t0 (mean interval 73 +/- 35 s). Coronary dilation was unchanged 1 min after t0 (18.3 +/- 5.4%, P less than 0.001) and was still present after 6 min (6.2 +/- 4.6%, P less than 0.01). With iopromide-370 coronary dilation at t0 was mild (5.4 +/- 4.3%; P less than 0.05); the subsequent injections led to minimal insignificant dilation. It is concluded that in quantitative angiographic studies on changes in coronary vasomotor tone repeated coronary angiograms should be taken with non-ionic contrast media; furthermore adequate injection intervals of greater than 3 min should be observed.

Adult↗

PubMed1989

Mitral prosthesis malfunction. Comparative Doppler echocardiographic studies of mitral prostheses before and after replacement.

To assess the influence of mitral prosthesis malfunction on various Doppler echocardiographic indexes, we studied the changes in the peak mitral flow velocity during early diastolic filling phase (Vmax), the mean transprosthesis pressure drop from the simplified Bernoulli equation, the mitral valve area by the pressure half-time method, and the left ventricular isovolumic relaxation time in 15 patients before and after replacement of the malfunctioning mitral prosthesis using continuous wave Doppler echocardiography. Examination of the 15 replaced prostheses revealed a torn or perforated leaflet in 12 valves and a sewing ring dehiscence in one valve. Additional restricted leaflet motion (classified as mild obstruction) was seen in three of these 13 valves. In the remaining two valves, severe prosthesis obstruction was noted. Changes in the Doppler indexes between the preoperative and postoperative study were present in all patients regarding Vmax (mean, 2.2 +/- 0.3 versus 1.6 +/- 0.2 m/sec; p less than 0.001), mean gradient (mean, 9 +/- 5 versus 5 +/- 0.8 mm Hg; p less than 0.001), and isovolumic relaxation time (mean, 47 +/- 12 msec versus 80 +/- 13 msec; p less than 0.001). The mean mitral valve area remained virtually unchanged (2.3 +/- 0.9 versus 2.6 +/- 0.3 cm2; p = NS) but increased postoperatively in each patient with preoperative mild or severe prosthesis obstruction without concomitant aortic regurgitation. Our conclusion is that the peak mitral flow velocity, the mean gradient, and the isovolumic relaxation time are useful parameters in the differentiation of normal and abnormal mitral prosthesis function but may not define the underlying lesion.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1989

Endothelium-dependent arterial vasoconstriction after balloon angioplasty.

To determine whether balloon angioplasty can provoke arterial vasoconstriction independent of platelet aggregation and neurogenic input, we studied the spontaneous vasomotor effects of balloon dilatation in isolated, perfused whole-vessel segments of rabbit aorta and pig carotid artery. Freshly dissected rabbit thoracic aortas were mounted in a muscle bath-perfusion chamber, perfused with physiologic saline solution at 70 mm Hg, and allowed to equilibrate. The proximal or distal half of the aortas were dilated with either a "large" (5 mm, 31-51% stretch beyond relaxed diameter) or a "small" (4 mm, 5-16% stretch) balloon angioplasty catheter with the other half of the vessel serving as the control. A similar series of experiments were performed in pig carotid arteries using "large" (6 or 8 mm, 48-90% stretch) balloon catheters. The spontaneous vasomotor effects of balloon angioplasty were examined with long-axis, high-frequency ultrasonic imaging combined with computerized edge detection image processing to measure changes in segmental internal vessel diameters. Additional experiments were carried out in rabbit aortas to determine the roles of the endothelium, extracellular calcium, indomethacin, ibuprofen, and calcium-channel blockade in modulating angioplasty-induced vasoconstriction. Significant arterial vasoconstriction was observed in the balloon angioplasty segments after dilatation with 5-mm balloons but not with 4-mm balloons. After dilatation with 5-mm balloons, the angioplasty segments' cross-sectional areas decreased by an average of 31% versus 4% for the nondilated (control) segments (p less than 0.0001). Similar postangioplasty vasoconstriction was observed in the pig carotid arteries (decrease in minimal vessel cross-sectional area of 41% [angioplasty segment] versus 2% [control segment]) (p less than 0.005). This angioplasty-induced vasoconstriction was prevented by endothelial denudation before angioplasty, removal of extracellular calcium, and pretreatment with indomethacin or ibuprofen. The vasoconstriction was only partially inhibited by calcium channel blockade with verapamil. These findings demonstrate that stretch-pressure-induced arterial vasoconstriction may occur after balloon angioplasty, independent of platelet aggregation and neurogenic input. This angioplasty-induced vasoconstriction appears to be mediated by an endothelially derived cyclooxygenase product(s).

Angioplasty, Balloon↗

PubMed1989

[Computer-assisted geometric measuring technic in coronary angiography interval studies: results of initial angiograms of the International Nifedipine Trial of Anti-atherosclerotic Therapy (INTACT) study].

In 396 of 423 (93.6%) patients with mild to moderate coronary artery disease participating in a coronary angiographic follow-up trial, diameters of the epicardial coronary arteries were measured with an automatic contour detection system (CAAS). The underlying INTACT study (International Nifedipine Trial on Antiatherosclerotic Therapy), a prospective, placebo-controlled, randomized, double-blind multicenter trial, investigates the influence of the calcium antagonist nifedipine (80 mg/day) on the progression of coronary atherosclerosis over a three-year interval. The study is based on coronary angiograms repeated in identical projections after premedication with 10 mg isosorbide dinitrate sublingually. For quantitative analysis the coronary artery system was, in consideration of all anatomical variations, subdivided into 25 segments. In the first angiograms of the 396 patients evaluated up to April 1, 1988, altogether 5,425 different coronary segments could be analyzed over their entire length in one or more angiographic projections--on the average 13.7 +/- 2.8 segments per patient. Analysis parameters were the mean diameters of the entire segments and of the individual subsegments (about 5 mm in length). The 10 major proximal segments could be evaluated in 76-94% of patients respectively in more than two different angiographic projections on the average; in 0-13% of patients the respective segments were occluded. In 1-4% of patients the evaluation of these segments was prevented by poor film quality and in 1-16% of patients prevented by anatomical abnormalities (e.g., segment too short or too small). 184 segments were found occluded (RCA 42%, LAD 30%, CX 28%) and 909 mostly low-grade to moderate stenoses (RCA 34%, CX 32%, LAD 30%, left main 4%) were analyzed with a special algorithm. The following obstruction parameters were derived: minimal diameter, percentage severity, length, and plaque area. The present data demonstrate that in an angiographical multicenter follow-up study such as INTACT a nearly complete quantitative morphometric analysis of the visualized coronary artery system can indeed be obtained in virtually all angiograms when a computer-assisted contour detection system is applied.

Clinical Trials as Topic↗

PubMed1988

Effects of acetylcholine on epicardial coronary arteries after cardiac transplantation without angiographic evidence of fixed graft narrowing.

The coronary response to acetylcholine was evaluated in 10 patients who had had cardiac transplantation 1 to 8 years earlier and in 4 patients who did not undergo transplantation. All 14 patients had no angiographic evidence of fixed coronary arterial narrowing. Acetylcholine was infused in 10-fold increasing concentrations (10(-6) to 10(-2) M) into the midpoint of the left anterior descending coronary artery by an infusion catheter. Administration was terminated when either vasoconstriction was noted at fluoroscopy or when the maximal acetylcholine concentration was reached. Vascular responses were evaluated by quantitative angiography. All 14 patients had a decrease in coronary lumen size in response to acetylcholine. The mean percentage of vasoconstriction was 37 +/- 24% (p less than 0.001). Combined infusion of nifedipine and the maximal vasoconstricting dose of acetylcholine did not result in a significant reversal of coronary vasoconstriction in all 10 cardiac transplantation patients. It was concluded that acetylcholine is a potent coronary vasoconstrictor in patients who had cardiac transplantation and possibly lacks vasodilating effects in most normal patients without angiographic evidence of coronary artery disease, thus suggesting that acetylcholine might not be a suitable pharmacologic agent for testing endothelial cell integrity.

Acetylcholine↗

PubMed1988

Clinical application of quantitative coronary angiography using the CAAS system: preliminary results of the INTACT study (International Nifedipine Trial on Antiatherosclerotic Therapy).

It is the objective of the INTACT-study to test in man, whether a significant retardation of the progression of coronary artery disease is attainable with the Ca-antagonist nifedipine; this may be possible on the basis of numerous animal experiments. INTACT is a prospective, randomized, double blind, placebo controlled investigation in 423 patients with preferably early stages of coronary sclerosis in whom a progression of the disease seems likely. A proper coronary angiogram led to inclusion of the patients in the study (October 1983-June 1985). Over the following 3-years-period patients received either nifedipine 80 mg/day or placebo. The study is concluded by a control coronary angiogram with angiographic projections which are identical to those of the first coronary angiography. The extent of coronary sclerosis is objectivated by computer-assisted quantitative measurement of the entire coronary arterial system with the CAAS-system (Rotterdam). For definition purposes the coronary artery system subdivided into 25 segments. Parameters for progression assessment will be mean segment diameter, minimal obstruction diameter, percentage severity of obstruction, length of obstruction and plaque area. So far 4826 coronary segments have been analyzed from the first angiograms of 383 patients. Per patient an average of 12.6 different segments could be evaluated in at least one angiographic projection. The major coronary segments could be measured in 72-93% of the patients in one or more angiographic projections (at the average about 2 different projections). Five hundred and forty-six coronary obstructions were analyzed; 131 of these were total occlusions. Only 9% of the length of the vessel contours detected by the computer algorithm required manual correction by the operators, suggesting a high reliability of the system. It can be concluded that quantitative measurement of the complete coronary artery system can indeed be obtained in a large angiographical multicenter study such as INTACT.

Angiography↗

PubMed1988

Left atrial spontaneous echo contrast in mitral valve disease: an indicator for an increased thromboembolic risk.

The incidence of left atrial spontaneous echo contrast was evaluated in 52 patients with isolated or predominant mitral valve stenosis (Group 1) and 70 other patients who had undergone mitral valve replacement (Group 2). All patients were studied by conventional transthoracic and transesophageal two-dimensional echocardiography. Spontaneous echo contrast could be visualized within the left atrium in 35 Group 1 patients (67.3%) (including 7 patients with sinus rhythm) and 26 Group 2 patients (37.1%) (all with atrial fibrillation). Patients with spontaneous echo contrast had a significantly larger left atrial diameter and a greater incidence of both left atrial thrombi and a history of arterial embolic episodes than did patients without spontaneous echo contrast. Association between spontaneous echo contrast and left atrial thrombi and a history of arterial embolization (considered individually or in combination) showed a high sensitivity and negative predictive value. It is concluded that spontaneous echo contrast is a helpful finding for identification of an increased thromboembolic risk in patients with mitral stenosis and after mitral valve replacement.

Adult↗

PubMed1988

Effects of nifedipine and nitrates on coronary vasomotion.

The diameter changes of angiographically normal coronary arteries following vasodilator drugs were studied in 41 patients. In group 1 (22 patients) angiograms and plasma levels were obtained before as well as 10, 20 and 30 minutes after 20 mg nifedipine s.l. (15 patients) or placebo (7 patients). A cluster analysis allowed a classification of patients into group A (N = 4) and B (N = 11) according to the slope of plasma level increase. Plasma levels A versus B were 27.8 +/- 9.8/13.5 +/- 4.5 ng ml-1; P less than 0.05; 54.0 +/- 11.7/21.7 +/- 6.6 ng ml-1; P less than 0.001; 79.1 +/- 9.3/28 +/- 9.8 ng ml-1; P less than 0.001. Corresponding diameter changes A versus B were: 7.3 +/- 5.1%/-5.6 +/- 9.0%; P less than 0.01; 11.4 +/- 4.1%/-4.5 +/- 11.3%; P less than 0.01; 14.5 +/- 5.9%/0.5 +/- 13.6%; P less than 0.05. In group 2 (N = 19) angiograms were obtained before as well as 2, 4, 7 and 15 minutes after administration of 10 mg isosorbide dinitrate (N = 9) or placebo (N = 10). Coronary dilation ISDN versus placebo was: 2.4 +/- 3.6%/0.9 +/- 4.0%; NS; 10.6 +/- 5.1%/3.1 +/- 3.8%; P less than 0.001; 12.3 +/- 5.9%/-0.3 +/- 6.4%; P less than 0.005; 10.5 +/- 6.5%/-4.0 +/- 7.7%; P less than 0.005. These data indicate that the interindividual variations of changes in coronary lumen size are due to different slopes of plasma level increase, most likely due to different rates of drug absorption after sublingual administration of nifedipine.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Sublingual↗

PubMed1988

Transesophageal two-dimensional echocardiography and color Doppler flow velocity mapping in the evaluation of cardiac valve prostheses.

To determine the value of transesophageal ultrasound in the assessment of cardiac valve prostheses, 14 patients with clinically suspected mitral prosthesis malfunction were studied by transthoracic and transesophageal two-dimensional imaging as well as by color Doppler flow velocity mapping (color Doppler). Patients underwent left ventricular angiography (n = 13), surgery (n = 11), or both angiography and surgery (n = 10). Nine patients had only mitral valve replacement, four patients had both mitral and aortic valve replacement, and one patient had mitral, aortic, and tricuspid valve replacement. There were 16 biological and four mechanical prostheses. The degree of mitral regurgitation was graded by both transthoracic and transesophageal color Doppler according to the area of the regurgitant jet visualized and was compared with a three-point classification of mitral regurgitation by left ventricular angiography judged by observers blinded to the echocardiographic results. All transesophageal studies were performed without complication and were well tolerated. The pathological morphology of the mitral prosthesis was additionally or more clearly visualized by transesophageal two-dimensional imaging and subsequently proven at surgery in three patients with flail leaflets and one patient with a vegetation compared with images obtained by the transthoracic approach. Valvular regurgitation was graded by the transthoracic approach as absent in four patients, mild in two patients, moderate in five patients, and severe in only three patients. The transesophageal assessment showed absence of mitral regurgitation in two patients, moderate regurgitation in two patients, and severe regurgitation in 10 patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗