Evolutive aortic stenosis in hemodialysis patients: analysis of risk factors.

Cardiovascular diseases represent the major cause of death in hemodialysis patients. However, little information is available about the repercussion of uremia on cardiac valves. We retrospectively investigated the incidence rate of aortic stenosis (AS), from 1991 to 1996, in 110 hemodialysis patients followed by Doppler-echocardiography. Progressive AS was diagnosed in 16 patients who had a decrease in their indexed aortic valve area from 1.24 +/- 0.09 to 0.66 +/- 0.21 cm2/m2 of BSA in 16.8 +/- 1.9 months. The mean incidence of AS per year was of 3.3%, ranging from 1.5 to 8.0%. Eight patients died in less than 3 years after the diagnosis of AS with a mean survival time of 23.0 +/- 9.5 months. Survival curves using Kaplan-Meier estimates showed a statistically significant decrease in the survival rate of patients with AS compared with patients without valvulopathy (p < 0.001). They were older than patients with normal valve, 68.6 +/- 11.1 versus 56.7 +/- 16.0 years, respectively. Men were 4 times more affected than women and showed a significantly more rapid progression to AS than women. The calcium-phosphorus product was higher in AS patients, 5.43 +/- 0.98 than in patients without AS, 3.95 +/- 0.50 mM. It was mainly due to hyperphosphatemia without hypercalcemia and the hyperphosphatemia was associated with biological signs of hypoparathyroidism or adynamic bone disease in 62% of the cases. Plasma vitamin D3 was also higher in patients with AS, 20.5 +/- 13.5 ng/ml than in those with normal valves, 9.6 +/- 6.3 ng/ml. Logistic regression showed that age, vitamin D3 and hyperphosphatemia correctly predicted 56% of the AS cases. In conclusion, AS is frequent and of poor outcome in hemodialysis patients. Age, relatively high plasma vitamin D3 levels, and hyperphosphatemia, mostly due to hypoparathyroidism, must be considered as risk factors.

[Recommendations of the French Society of Cardiology for the training of echocardiographers and performing echocardiograms]. / Recommandations de la Société Française de Cardiologie concernant la formation des échocardiographistes et la réalisation des échocardiogrammes.

The considerable advances achieved in the field of echocardiography have made this investigation an essential diagnostic tool. Under the auspices of the French Society of Cardiology, the Working group on Echocardiography publishes its practical recommendations for optimising the training of echocardiographers (theoretical instruction and practical courses) and for performing echocardiography (understanding the clinical problem, referral to previous examinations, necessary recordings and measurements, and appropriate equipment). In the future, these recommendations should be updated to take into account continuing technical improvements and changes in methods of studying cardiac disease by echocardiography.

Coronary artery revascularisation without extracorporeal circulation. Indications and results.

OBJECTIVE: Coronary artery revascularisation without extracorporeal circulation is a technique which can be performed in selected patients in need of a coronary artery bypass graft. METHODS: Consecutive patients (210) underwent coronary artery bypass graft without extracorporeal circulation. Indications were high risk patients, or single coronary artery lesion. To predict perioperative mortality, preoperative risk factors were reviewed, and Parsonnet score was calculated. RESULTS: There were seven deaths (3.3%), and univariate analysis revealed greater age, NYHA, and poor ejection fraction to be the only predictors of early mortality. Perioperative myocardial infarction included 15 patients (7.1%), most of them seen in the multiple bypass group (10/39, 26%). Patients were divided into low risk (Parsonnet score < 15) 155 patients with two deaths (1.2%), and high risk (Parsonnet score > 15) 55 patients with five deaths (9%). Complete revascularisation was performed in the low risk group, while in the high risk only the symptomatic vessel was bypassed and other angiographic lesions treated with postoperative angioplasty (10 patients). A total of 12 patients developed early postoperative angina (5.7%), 9 presented an anastomosis dysfunction which was treated by angioplasty (5) and surgery (4), and 188 patients (85.7%) did not receive transfusions while 190 patients (90.4%) did not need postoperative inotropes. Length of stay, operating room time, and medical costs were all significantly reduced. CONCLUSIONS: Myocardial revascularisation without extracorporeal circulation can be performed with a low operative mortality, and minimal morbidity only in patients undergoing single bypass revascularisation. It can also be performed as part of a multiple revascularisation strategy in association with angioplasty in high risks patients.

Calcified embolus of the left coronary ostia after aortic valve replacement.

A patient with a left coronary calcified embolus causing acute myocardial dysfunction immediately after aortic valve replacement is described. Prompt diagnosis by transesophageal echocardiogram was made, which led to removal of the embolus and a subsequent satisfactory course.

[Incidence and development of aortic stenosis in chronic hemodialysis. An ultrasonographic and biological study of 112 patients]. / Incidence et évolutivité des rétrécissements aortiques chez l'hémodialysé chronique. Une étude échographique et biologique sur une population de 112 patients.

Valvular calcification in chronic haemodialysis patients has already been reported in the literature, particularly the abnormally high incidence of aortic stenosis. In this study, 112 haemodialysis patients were followed up by Doppler echocardiography for a period of 36 months. Sixteen patients developed aortic valvular calcification with aortic stenosis over an 18.7 +/- 7.5 months period. The indexed aortic valve surface area decreased from 1.24 +/- 0.9 cm2/m2 to 0.66 +/- 0.21 cm2/m2 with abnormally rapid progression. Eight patients with aortic stenosis died during the 3 year study period. These results reflect the abnormal extra-skeletal calcification of chronic haemodialysis patients. Several predisposing factors were demonstrated: age (68.5 +/- 11.1 years versus 57.1 +/- 16.3 years in patients without calcifications), male gender, a longer period of dialysis than the patients without aortic stenosis (8.1 +/- 5.3 versus 5.9 +/- 5.7 years), abnormalities of calcium and phosphate metabolism, increased of the phosphocalcic product by hyperphosphoraemia and not by hypercalcaemia, hypoparathyroidism in 62% and hyperparathyroidism in 38% an increase in vitamin D 3 (19.7 +/- 14 ng/ml versus 9.6 +/- 6.3 ng/ml) biological signs of adynamic osteodystrophy. Calcific aortic stenosis is a commonly observed valvular lesion in haemodialysis patients: its progression may be very rapid, associated with a poor prognosis. Old age, male gender, duration of haemodialysis, hyperphosphataemia associated with hypoparathyroidism and raised Vitamin D3 are predisposing factors.

[Contribution of multiplane transesophageal echocardiography in the study of mitral valve prostheses]. / Apport de l'échographie transoesophagienne multiplan dans l'étude des prothèses mitrales.

Many reports have confirmed the value of transoesophageal echocardiography in the diagnosis of mechanical mitral valve prosthesis dysfunction: new biplane and multiplane probes seem to provide additional information in the assessment of cardiac disease. The aim of this study was to quantify the additional value of these new probes in the assessment of mitral valve prostheses. Seventy-five mitral valve prostheses were assessed with the multiplane probe, 45 normal bileaflet prostheses, 17 with regurgitant dysfunction and 12 with non obstructive thrombi and/or strands, and one with a blocked leaflet. In order to compare the respective values of monoplane, biplane and multiplane probes, the recordings were performed at 0 degrees, 90 degrees and from 0 degrees to 180 degrees in continuous sweep mode through the scanning plane. Globally, with the monoplane assessment, it was only possible to visualise both leaflets simultaneously in 13% of cases. The majority of prostheses was correctly analysed between 60 and 100 degrees. This was of paramount importance for the diagnosis of blockage of one leaflet. With respect to para-prosthetic valve regurgitation, the transverse view allowed visualisation of the lateral and paraseptal annular regions. The addition of a longitudinal view allowed visualisation of anterior and posterior regurgitant jets: the supplementary views provided by the multiplane probe allowed detection of small regurgitant jets in the diagonal planes between the longitudinal and transverse views. The multiplane probe offers the possibility of identifying the precise origin of the jet and helps quantification and peroperative localisation of its position. Small, non-obstructive thrombi and strands are better seen using a multiplane probe, especially when of small size. Therefore, multiplane transoesophageal echocardiography improves the assessment of mitral valve prostheses, the majority of diagnoses being, however, accessible with biplane probes.

[Guidelines of the French Society of Cardiology on the training of echocardiographers and the performing of echocardiography]. / Recommandations de la Société française de cardiologie concernant la formation des échocardiographistes et la réalisation des échocardiogrammes.

The considerable advances achieved in the field of echocardiography have made this investigation an essential diagnostic tool. Under the auspices of the French Society of Cardiology, the Working group on Echocardiography publishes its practical recommendations for optimising the training of echocardiographers (theoretical instruction and practical courses) and for performing echocardiography (understanding the clinical problem, referral to previous examinations, necessary recordings and measurements, and appropriate equipment). In the future, these recommendations should be updated to take into account continuing technical improvements and changes in methods of studying cardiac disease by echocardiography.

[Late potentials and mitral valve prolapse]. / Potentiels tardifs et prolapsus valvulaire mitral.

Signal averaged electrocardiogrammes were recorded in 100 consecutive patients with echocardiographic mitral valve prolapse (MVP) and compared with 50 normal control subjects. Criteria of normality were defined in the reference population: QRS duration after averaging < 113 ms, Simson's vector of the last 40 ms (RMS40) > or = 17 microV, and duration of the terminal potential within the 40 microV range < 38 ms, using a high-pass bidirectional 40 Hz filter. Of the 100 patients with MVP, late ventricular potentials (LP) were recorded in 38 cases with at least 2 criteria of positivity, compared to only 3 out of 50 (6%) in the control group (p < 0.01). The prevalence of LP was very dependent on the appearances of the valve; when the valve was of normal thickness and only showed slight systolic bulging there were only 5/46 cases of LP (10.9%) which did not differ significantly from the control group. On the other hand, when the valve showed myxoid changes, the prevalence of LP was very high: 33/54 = 61% (p < 0.001 versus controls). Six patients had severe ventricular arrhythmias (sustained ventricular tachycardia or ventricular fibrillation): all had LP. In cases of MVP with frequent ventricular extrasystoles (VEs) the prevalence of LP was the same with normal valves (2/23 = 9% and 2/22 = 9%, NS) whereas LPs were more common in cases of VEs with myxoid valve (23/33 = 70% versus 5/16 = 31%; p = 0.01). The high prevalence of LP in MVP with myxoid valves is a convincing argument in favour of myocardial abnormality in this disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Percutaneous double balloon valvuloplasty for stenosis of porcine bioprostheses in the tricuspid valve position: a report of 2 cases.

The feasibility and results of percutaneous double balloon valvuloplasty were evaluated in 2 patients with stenosis of porcine bioprostheses in the tricuspid valve position. The procedures were performed with a Trefoil 3 x 10 and a 15 mm balloon. Long inflations (4 and 3 minutes) were well tolerated. A significant immediate increase in the valve area, without significant valvular regurgitation, was achieved in both cases, from 0.65 to 1.15 cm2 in case 1 and from 0.9 to 1.65 cm2 in case 2. Both patients required valve replacement during the follow-up, at 14 and 21 months. There was no restenosis, but echocardiography showed right atrial thrombosis in case 1. Progressive restenosis with peripheral edema and increase of the mean doppler gradient occurred in case 2. The procedure is feasible, safe, and well tolerated. It provides significant immediate hemodynamic improvement, but it should be considered as a palliative technique since a normal valve area can not usually be obtained and a restenosis is likely to occur at midterm follow-up.

[Value of early systematic postoperative transesophageal echocardiography in mitral valve replacements. A prospective study of 50 patients]. / Intérêts de l'échocardiographie transoesophagienne systématique postopératoire précoce des remplacements valvulaires mitraux. Une étude prospective sur 50 patients.

The aim of this study was to assess the value of routine transoesophageal echocardiography in the early postoperative period after mitral valve replacement. The authors report their experience in 50 consecutive operated patients (43 mechanical and 7 bioprostheses) investigated routinely by this method in the postoperative period in the surgical unit. Abnormal findings were observed in 36% of cases (18 patients): trans-prosthetic leaks (8 cases) and thrombosis (10 cases) in 2 bioprostheses and 8 mechanical prostheses; in 3 cases this led to haemodynamic dysfunction but in 7 cases the thrombus had no influence on the trans-prosthetic pressure gradient. No predisposing factor could be identified (spontaneous contrast, left atrial volume, left ventricular function, poor anticoagulation, blood clotting abnormalities). No abnormality of the mobile components of the prosthesis was observed at radioscopy. The outcome with heparin therapy was favourable with disappearance of the thrombi in 6 cases; the thrombi did not regress in 4 patients on heparin: 2 patients underwent thrombolytic therapy with a complete cure in 1 case and a severe embolic complication in the other; in 2 cases, the thrombus was so big that the patients were reoperated. Systematic early postoperative transoesophageal echocardiography before discharge from the surgical unit would seem to be necessary after early mitral valve replacement: it allows diagnosis of asymptomatic thrombosis which has an important emboligenic potential. The management of these thromboses remains controversial, but the poor natural outcome in cases of large thromboses should lead to referral for early reoperation.

[Asymptomatic postoperative thrombosis of a Saint Jude mitral valve prosthesis. Treatment by fibrinolysis with rt-PA]. / Thrombose postopératoire asymptomatique d'une valve de Saint-Jude mitrale: traitement par fibrinolyse au rt-PA.

Routine Doppler echocardiography after cardiac surgery demonstrated stenotic dysfunction of a Saint Jude Medical mitral valve prosthesis due to blockage of one hemidisc although the patient was totally asymptomatic. Despite the precocity of this thrombosis (14th postoperative day), thrombolytic treatment was undertaken. It led to normalisation of the Doppler parameters of prosthetic valve function and mobility of the two hemidiscs. Haemopericardium occurred at the end of thrombolytic therapy and was drained easily, a benign complication of early postoperative thrombolysis.

[Color Doppler echocardiography]. / L'échocardiographie Doppler couleur.

Colour-coded doppler echocardiography uses a pulsed doppler shooting lines scanning system to perform a true real-time doppler angiography of intracradiac flows. Combined with ultrasonic imaging, it has proved irreplaceable for the diagnosis of leakages and for direct visualization of intracradiac shunts; by determining the anatomical location of the jet it facilitates an accurate pulsed and continuous Doppler study. Aortic leakages are best evaluated by measuring the jet at its point of origin. The quantification of moderate to medium leakages remains difficult since it depends on numerous factors and needs integration of other echocardiographic data. Echocardiographic contrast tests after intravenous injection of microbubbles diagnose the right-to-left shunts by the passage of contrast into the left cavities, and the left-to-right shunts by a washing image.

[Quantitative analysis of ventricular volumes by digital two-dimensional echocardiography]. / Analyse quantitative des volumes ventriculaires par échocardiographie bidimensionnelle numérisée.

The purpose of this study was to assess the usefulness of digital enhancement of two-dimensional echocardiographic images by cardiac cycle-synchronized summation and digital manipulation of the resulting images. We developed a system which provides for: (1) real-time storage of end-diastolic and end-systolic cardiac cycle images irrespective of rhythm variations; (2) exclusion from summation of end-diastolic and end-systolic images altered by respiratory movements or transducer displacements; (3) performance on the resulting images of various mathematical operations (3*3 convolutions, colour scale-guided manipulation of grey shades); (4) performance of complex mathematical calculations from the extracted edges including, in particular, reconstruction of ventricular volumes by Simpson's crossed method from a transverse and an apical section or from two apical sections. This method was used to collect echocardiographic images from 32 patients who had undergone left ventricular quantitative angiography during the same week. Qualitatively, digital enhancement of two-dimensional echocardiographic images undoubtedly facilitated the identification of endocardial edges and reduced image noise, notably in patients whose ventricular edges were virtually unrecognizable by any other method. Moreover, summation improved correlations with angiography and reduced the variability of quantitative ventricular volume assessment. Finally, the ease and rapidity with which this "real-time" system can be used enables quantitative analysis of left ventricular function to be routinely carried out.

[Doppler echocardiography in dysfunctions of valvular prostheses: diagnostic and quantitative significance. Apropos of 20 cases]. / L'échocardiographie Doppler dans les dysfonctions de prothèses valvulaires: intérêt diagnostique et quantitatif. A propos de 20 cas.

We present a retrospective study of 20 patients with cardiac valve prosthetic dysfunction who required reoperation and underwent pre-operative doppler echocardiography. There were 13 cases of mitral valve prosthesis (3 mechanical, 10 xenografts), 5 cases of aortic valve prosthesis (1 mechanical, 4 xenografts), 1 pulmonary valve bioprosthesis and 1 tricuspid valve mechanical prosthesis. Our purpose was to evaluate the diagnostic and quantitative value of this examination in prosthetic dysfunction by comparing doppler data with anatomical findings at surgery. The parameters measured were peak and mean pressure gradients in all cases, gradient half-decrease time and valve surface calculated therefrom in mitral and tricuspid valve prostheses. The results of doppler examination were compared with per-operative anatomical findings in 6 cases, and pre-operative haemodynamic exploration was performed in one case. The diagnosis of prosthetic stenosis was found to be correct in all patients, even in those with moderate stenosis. All leaks and their locations were diagnosed, except in a mitral valve mechanical prosthesis where leaking was detected by continuous doppler. 14 out of the 20 patients were reoperated upon without catheterization. These results suggest that doppler examination is a sensitive and specific method for evaluating cardiac valve dysfunction. However, variations in doppler results from one prosthesis to another make it necessary to perform pulsed and continuous doppler at the end of the operation to be used as reference if dysfunction is suspected subsequently.