Valve strands are strongly associated with systemic embolization: a transesophageal echocardiographic study

OBJECTIVES: We attempted to determine the prevalence of strands on native and prosthetic valves, as detected by transesophageal echocardiography, and to assess the relative risk for systemic emboli associated with these strands. BACKGROUND: Fine threadlike strands, seen on native and prosthetic valves by transesophageal echocardiography, have been implicated in systemic embolization. METHODS: During a 2-year period, 1,559 patients underwent transesophageal echocardiography at our center. Of these, 41 patients had strands and no other identifiable source of systemic emboli. They were matched for age, gender, history of hypertension and history of smoking with a control group of 41 patients without strands who also had no identifiable source of emboli. The risk of embolization in the two groups was compared. RESULTS: Of 1,559 patients studied by transesophageal echocardiography, 86 (5.5%) had strands. Strands were far more common on mitral valves than on aortic valves. Of the patients with strands, 38% had had an event consistent with a systemic embolus, whereas 62% had not. Of 597 patients with an embolic event, 63 (10.6%) had strands, whereas only 23 (2.3%) of 962 patients without emboli had strands. In the case-control study, 33 (83%) of the 41 patients with strands without another source of embolism had emboli compared with only 12 (29%) of the 41 control patients without another source (odds ratio 10.0, 95% confidence interval 3.6 to 27.8, p = 0.00001). CONCLUSIONS: Valvular strands visualized by transesophageal echocardiography are associated with systemic embolization.     

Susceptibility to varicella zoster virus infection in health care workers

Doppler ultrasound detection of abnormally high-pitched signals within the arterial waveform offers a new method for diagnosis, and potentially for prediction, of embolic complications in at-risk patients. The nature of Doppler "microembolic" signals is of particular interest in patients with prosthetic heart valves, where a high prevalence of these signals is observed. Monitoring the middle cerebral artery with 2-MHz transcranial Doppler ultrasound (TC-2000, Nicolet Biomedical; Warwick, UK), we looked for microemboli signals in 150 patients (95 women and 55 men), and found 1 or more signals during a 30-min recording in 89% of 70 patients with Bjork-Shiley valves (principally monostrut), 54% of 50 patients with Medtronic-Hall valves, and 50% of 30 patients with Carpentier-Edwards valves (p < 0.001, chi 2). In the patients with Bjork-Shiley valves, the mean number of signals per hour was 59 (range, 42-86; 95% confidence interval), which was significantly higher than the mean in patients with Medtronic-Hall and Carpentier-Edwards valves (1.5[range, 0.5-2.5] and 1 [range, 0-5.3], respectively; both p < 0.04, multiple comparisons. Bonferroni correction). In the patients undergoing serial pre- and postoperative studies, the causative role of the valve implant was emphasized. There was no correlation between the number of emboli signals and a prior history of neurologic deficit, cardiac rhythm, previous cardiac surgery, or the intensity of oral anticoagulation, in patients with prosthetic heart valves. In Bjork-Shiley patients, dual (mitral and aortic) valves were associated with more signals than were single valves. In Medtronic-Hall patients, the signal count was greater for valves in the aortic position than it was for valves in the mitral position. Comparative studies of Doppler emboli signals in other clinical settings suggest a difference in composition or size of the underlying maternal between prosthetic valve patients and patients with carotid stenosis. These studies also suggest that the signals are of gaseous origin in valve patients. The clinical significance of continuing microembolism remains to be determined.     

Idiopathic mitral valve prolapse-analysis by real-time two-dimensional echocardiography

Mitral valve prolapse is diagnosed in real-time two-dimensional echocardiograms when there are discrepancies in the coaptation zone of the anterior mitral leaflet and the posterior mitral leaflet. Out of the 100 cases of mitral valve prolapse diagnosed in this way, 65 had prolapsed anterior mitral leaflets, 28 prolapsed posterior mitral leaflets and 7 prolapses of both the anterior and posterior mitral leaflets. In addition to the cases with mitral valve prolapse 23 cases of ruptured chordae tendineae of the mitral valve, including 15 cases which had undergone surgery, were investigated. The frequent site of mitral valve prolapse was the posteromedial commissure in the anterior leaflet and the posteromedial and anterolateral commissures in the posterior leaflet. These sites coincide with those where rupture of the chordae tendineae of the mitral valve was apt to occur. An investigation of the relation between age and mitral valve prolapse showed that the number of cases of prolapsed anterior leaflet did not increase with age, but there was an age-related increase in the number of cases of prolapsed posterior leaflets. It was also found that the degree of the prolapse progressed with age. Many of the cases of ruptured chordae tendineae of the mitral valve were in their forties or fifties, and there appeared to be some relation between the progress of the prolapse and age. Mitral regurgitant murmurs were recorded on phonocardiograms, and the severer the degree, the wider the range of the prolapse. Mitral regurgitation was more likely to occur in cases of prolapsed posterior leaflets than in those with prolapsed anterior leaflets, even if the degree and the range of the prolapse were mild.     

Cineangiographic diagnosis of papillary muscle involvement in rheumatic mitral stenosis

Left ventricular cineangiography was performed in 25 patients with normal mitral valves and in 49 patients with rheumatic mitral valve disease to estimate the spatial relations between the mitral valve leaflets and papillary muscles. The findings in the pathologic group were compared with observations at operation or with the excised mitral valves. It is concluded that fusion of the papillary muscles with the mitral valve leaflet or severe shortening of the chordae is predicted with a reasonable accuracy preoperatively by means of left ventricular cineangiography. The surgical implications are discussed.     

Pathology of mitral valve stenosis and pure mitral regurgitation--Part I

This two-part article examines the histologic and morphologic basis for stenotic and purely regurgitant mitral valves. In Part I, conditions producing mitral valve stenosis are reviewed. In over 99% of stenotic mitral valves, the etiology is rheumatic disease. Other rare causes of mitral stenosis include congenital malformed valves, active infective endocarditis, massive annular calcium, and metabolic or enzymatic abnormalities. In Part II, conditions producing pure mitral regurgitation will be discussed. In contrast to the few causes of mitral stenosis, the causes of pure (no element of stenosis) mitral regurgitation are multiple. Some of the conditions producing pure regurgitation include floppy mitral valves, infective endocarditis, papillary muscle dysfunction, rheumatic disease, and ruptured chordae tendinae.     

Retinal stroke. Is the patient at risk?

A follow-up study was performed to determine the general prognosis for health and life in 86 patients with retinal artery occlusion or ophthalmoscopically observed retinal cholesterol emboli, not subjected to surgery. Survivorship rates and incidence of subsequent cerebrovascular disease were calculated and compared to expected survivorship rate of an age-and sex-matched population. Results were as follows: the patient group with retinal stroke as a whole showed a statistically significant diminished survivorship rate from the third year onward; patients with retinal occlusions without visible emboli had a survivorship rate comparable to the matched control; but patients with visible emboli demonstrated a strikingly diminished survivorship rate. In the study group, the combined time corrected annual stroke mortality was 1,695 per 100,000 (four to five times greater than expected), but the largest single cause of death was cardiovascular disease.     

Mitral valve prolapse. Recent concepts and observations

The conditions associated with prolapse of the posterior leaflet of the mitral valve are multiple. The mechanisms of mitral valve prolapse as well as the pathogenesis of pain and ectopic impulse formation are reviewed. Propranolol appears to be the drug of choice for the symptomatic treatment of patients with this syndrome since it decreases myocardial oxygen demand and wall tension thus reducing or abolishing the discrepancy between myocardial oxygen demand and supply within the mitral apparatus. It has also been reported to modify the auscultatory findings associated with this condition. The frequency of this mitral valve abnormality in patients with obstructive coronary artery disease is reviewed. It appears that prolapse of the posterior leaflet scallops in patients with significant obstructive coronary artery disease represents an intermediate stage before mitral insufficiency occurs. This group of patients with papillary muscle dysfunction includes those with prolapsed leaflets without mitral insufficiency, those with systolic murmurs and compensated heart failure and others with progressive cardiac decompensation and severe mitral regurgitation.     

Cardiology: prolapsed mitral valve syndrome

A patient with the prolapsed mitral valve syndrome may have no symptoms referable to the heart or, at the other extreme, may have disabling chest pain, severe arrhythmias, and electrocardiographic abnormalities. The syndrome is characterized by a midsystolic click and a late systolic murmur. The mechanism responsible for the valve deformity appears to be related to myxomatous degeneration. Associated ECG abnormalities strongly suggest myocardial disease. The diagnoses is established by echocardiography or cineangiocardiography.     

Myxoma of the mitral valve prolapsing into the left atrium and ventricle: report of a case

A rare case of myxoma originating from the mitral valve is reported. A 25-year-old woman was found to have a mobile mass around the mitral valve that prolapsed into the left atrium and the left ventricular outflow tract. The mitral valve was approached via the left atrium and aorta, and was excised completely along with the tumor; it was thus replaced with a mechanical prosthesis. The patient recovered and demonstrated no signs of recurrence 16 months postoperatively.     

Right thoracotomy to approach mitral or tricuspid valve in reoperation

Four patients underwent mitral valve re-replacement, and required tricuspid annuloplasty in two, through a right thoracotomy. There was no major postoperative morbidity and recovery was full and uneventful. The indications for selection of this approach were isolated mitral valve disease or combined tricuspid and mitral valve disease, severe adhesion between heart and sternum on CT scan, intact aortic valve and no severe reduction of respiratory function. We recommend right thoracotomy to approach atrioventricular valves in selected situations in patients for reoperations.     

Expression of microfibrillar proteins by bovine bladder urothelium

OBJECTIVE: To compare hydrodynamic characteristics of a new bileaflet heart valve, the CarboMedics kinetic cardiac valve prosthesis, with those of a St. Jude Medical (SJM) heart valve. METHODS: Hydrodynamic characteristics were determined in the mitral and aortic positions of a Vivitro Systems pulse duplicator for size 23 Kinetic aortic values, size 23 SJM aortic valves, size 29 Kinetic mitral valves and size 29 SJM mitral valves. Test conditions were 72 beats per min with cardiac outputs of 2, 5 and 7 l/min. Values of forward flow pressure drop (delta P), regurgitant and energy loss were determined for each valve. The test results for the two valve designs were compared by valve size. RESULTS: The test results show that both the size 23 and size 29 Kinetic valves have 8-14% lower delta P values and 5-10% greater effective orifice area (EOA) values. The size 29 Kinetic mitral valve has a 1-2 ml lower regurgitant volume, while the size 23 Kinetic aortic valve has a 0.5 ml greater regurgitant volume than the corresponding SJM values. These factors combine to provide a 5-10% lower energy loss for size 23 Kinetic aortic valves and a 15-25% lower energy loss for size 29 Kinetic mitral valves over the cardiac cycle than for corresponding sizes of SJM valves. CONCLUSIONS: The Kinetic valve's fluid dynamics are superior to equivalent sizes of SJM valves. This is especially impressive considering that the tissue annulus diameters for Kinetic valves are approximately 0.5 mm less than equivalent size SJM valves. The primary reasons for the superior hydrodynamic performance of Kinetic valves are (1) the larger orifices which result in lower forward flow delta P values and (2) the opening angles, which have been customized for each valve size to minimize energy loss.     

Heart valve replacement with the Ionescu-Shiley pericardial xenograft

Between March, 1971, and September, 1975, glutaraldehyde-stabilized pericardial xenografts were used for single valve replacement in.212 patients (142 aortic, 67 mitral, and three tricuspid). The 195 operative survivors were observed for a total of 5,926 months over a period 6 to 61 months (mean 30). actuarial analysis of late results indicates an expected survival rate at 5 years of 92.3 per cent for patients with aortic and 91.1 per cent for patients with valve replacement. The rate of systemic embolism has been 0.62 episodes per 100 patient years for the aortic and 2.48 episodes per 100 patient years for the mitral group in the absence of anticoagulant treatment. All six emboli occurred early postoperatively, were trivial or mild, and left no sequelae. Symptomatically, 96.7 per cent of patients are now in Class I and 3.3 per cent in Class II (N.Y.H.A.). Maintenance of structural and functional integrity of the glutaraldehyde-stabilized pericardial zenograft was demonstrated by histologic and hemodynamic investigations. Catheterization showed substantial circulatory improvement in both patients with aortic and those with mitral replacement. The transaortic gradients were negligible (8 mm. Hg at rest and 17.5 mm. Hg during exercise). The available indicates that results of valve replacement withpericardial xenografts. Over this period of follow-up, compare very favorably with those obtained with other available prostheses and tissue valves.     

Apical cross-sectional echocardiography. Standard for the diagnosis of idiopathic mitral valve prolapse syndrome

In light of the nonspecificity of left ventricular angiography and physical examination, and the limitations of M-mode echocardiography to define the presence of mitral valve prolapse syndrome, we evaluated left ventricular longitudinal and apical four-chamber tomographic views of cross sectional echocardiography in 19 subjects with normal left ventricular cineangiography and in 5 patients with congestive cardiomyopathy. None had auscultatory findings suggestive of mitral valve prolapse syndrome. In all 24 control subjects, the apical view demonstrated the coaptation point and the leaflets of the mitral valve to lie inside the left ventricular cavity. A retrospective analysis of 900 consecutive cross sectional echocardiographic studies revealed 105 subjects with no evidence of structural heart disease other than the presence of the mitral valve leaflets in the left atrium in systole defining the existence of idiopathic mitral valve prolapse syndrome. Both mitral leaflets were prolapsed in 90 percent of the involved populations, and the apical tomographic cross sectional echocardiographic view was superior to the left ventricular longitudinal view for the detection of anterior leaflet prolapse. These data suggest that the apical cross sectional view may be the single best technique to define the presence of idiopathic mitral valve prolapse syndrome.     

Urethral diseases in children at surgical departments of the Cotonou Hospital. Apropos of 77 cases

Over a 6-year period in the surgical departments of Cotonou hospital, urethral diseases in children represented 20% of all infantile urological diseases and essentially consisted of urethral strictures (26 cases), hypospadias (22 cases), posterior urethral valves (12 cases), prolapsed urethral mucosa, the only disease observed in girls (9 cases). These diseases generally do not raise any diagnostic problems, but the real problem concerns follow-up of these children, who are usually lost to follow-up after discharge.     

Detection of asymptomatic cerebral embolic signals with Doppler ultrasound

Can asymptomatic cerebral emboli be detected? With transcranial Doppler ultrasonography of the middle cerebral artery, short-duration high-intensity asymptomatic embolic signals were detected in 6 of 25 patients with carotid stenosis and in 9 of 24 with prosthetic cardiac valves, but not in 20 normal controls. In carotid stenosis the signals were usually unilateral and ipsilateral to the stenosis. Embolic signals were significantly more common in patients with mechanical valves than with pig xenografts (8/13 vs 1/11). With mechanical valves embolic signals were usually bilateral. Detection of asymptomatic emboli may allow identification of and preventive treatment in at-risk patients.     

Acute mitral insufficiency in osteogenesis imperfecta

A 56-year-old woman with known osteogenesis imperfecta tarda but no obvious sign of cardiac disease developed increasing dyspnoea, eventually even at rest, with blood-streaked sputum over a period of 10 days. The chest radiograph demonstrated intraalveolar pulmonary oedema. Transthoracic echocardiography revealed as the likely cause of these signs chordal rupture of the anterior leaflet of the mitral valve with mitral regurgitation. After treatment of the cardiac failure with frusemide (up to 500 mg daily intravenously), nitrates and captopril (25 mg daily by mouth) the diagnosis was confirmed by transoesophageal echocardiography. Elective replacement of the mitral and aortic valves was performed 6 months later. Acid mucopolysaccharides were demonstrated histologically in the valvar stroma, a finding consistent with osteogenesis imperfecta. Echocardiography should be performed routinely in connective-tissue disease to reveal any possible cardiovascular involvement.     

A comparison of outcomes in men 11 years after heart-valve replacement with a mechanical valve or bioprosthesis. Veterans Affairs Cooperative Study on Valvular Heart Disease

BACKGROUND: Mechanical heart valves are durable but thrombogenic, and their use requires that the patient receive anticoagulants. In contrast, bioprosthetic valves are less thrombogenic, but they have limited durability because of tissue deterioration. METHODS: To compare the outcomes of patients who receive these two types of valves, we randomly assigned 575 men scheduled to undergo aortic-valve or mitral-valve replacement to receive either a mechanical or a bioprosthetic valve. The primary end points were death from any cause and any valve-related complication. RESULTS: During an average follow-up of 11 years, there was no difference between the two groups in the probability of death from any cause (11-year probability for mechanical valves, 0.57; for bioprostheses, 0.62; P = 0.57) or in the probability of any valve-related complication (0.65 and 0.69, respectively; P = 0.39). There was a much higher rate of structural valve failure among patients who received bioprosthetic valves (11-year probability, 0.15 for the aortic valves and 0.36 for the mitral valves) than among those who received mechanical valves (no valve failures; P < 0.001). However, this difference was offset by a higher rate of bleeding complications among patients with mechanical valves than among those with bioprosthetic valves (11-year probability, 0.42 and 0.26, respectively; P < 0.001) and by a greater frequency of peri-prosthetic valvular regurgitation among patients with mechanical mitral valves than among those with mitral bioprostheses (11-year probability, 0.17 and 0.09, respectively; P = 0.05). CONCLUSIONS: After 11 years, the rates of survival and freedom from all valve-related complications were similar for patients who received mechanical heart valves and those who received bioprosthetic heart valves. However, structural failure was observed only with the bioprosthetic valves, whereas bleeding complications were more frequent among patients who received mechanical valves.     

Haemophilus paraphrophilus endocarditis in a prolapsed mitral valve

A case of Haemophilus paraphrophilus endocarditis successfully treated with ampicillin is described. The patient, a 24-year-old woman, had a prolapsed mitral valve. The organism was initally misidentified as H. parainfluenzae, which it closely resembles. H. paraphrophilus is distinguished by its requirement of 10% CO2 for growth on NaCl-free medium and its inability to ferment xylose.     

Reoperation for mitral regurgitation 13 years after aortic valve replacement and manouguian's anulus enlargement: report of a case

The patient was 22-year-old female. She had undergone aortic valve replacement and Manouguian's anulus enlargement with low porosity woven Dacron patch for congenital aortic stenosis 13 years ago, and developed mitral regurgitation 9 years after that operation. Two regurgitant flow were observed. One was originated from the orifice due to mitral prolapse. The other was from a tear in the anterior leaflet. It was around the tip of the prosthetic patch, approximately 7 mm in size, and was repaired easily. But the mitral valve itself was found to be malformed and prolapsed, requiring mitral valve replacement. Her postoperative course was uneventful.     

Mitral valve repair vs replacement. Current recommendations and long-term results

Techniques now exist to correct abnormalities of all components of the mitral valvular apparatus except extensive loss of pliable leaflet area. Thus, paradoxically, myxomatous valves with redundant leaflets represent the ideal candidates for mitral valve repair. Repair for mitral insufficiency can be performed for some rheumatic valves, but patient selection is critical. Loss of leaflet area, leaflet thickening, and extensive calcification of the leaflets or commissures are contraindications to repair. The abnormalities of the subvalvular apparatus are less important because a complete set of new chordae can be reconstructed using PTFE suture material. Some cases of endocarditis are ideal for repair using localized débridement and pericardial patch repair with or without PTFE chordal replacement. True ischemic mitral regurgitation of the Carpentier type I category is still something of a surgical enigma. Because it is a restrictive leaflet motion problem, annuloplasty alone is not always effective, and the outcome of any given repair attempt is less predictable. Repairs in patients with small annuli and multiple leaflet defects requiring complex series of maneuvers have a low probability of success. Furthermore, such patients with small left ventricular cavities are more prone to experience SAM. Several factors contributing to which therapy is chosen for mitral valve disease are summarized in Table 1. Patient selection, accurate evaluation of the cause or causes of mitral regurgitation, and well-executed application of the appropriate techniques for repair are all critical factors in the early and late success of mitral valve repair.