Comparison of clinical and echocardiographic characteristics of Streptococcus bovis endocarditis with that caused by other pathogens

The aim of our study was to compare the clinical, echographic, and prognostic features of Streptococcus bovis (S. bovis) endocarditis with those caused by other streptococci and pathogens in a large sample of patients with definite endocarditis by Duke criteria, using transesophageal echocardiography. Two hundred six patients (149 men, mean age 57 +/- 15 years) with a diagnosis of infective endocarditis formed the study population. All patients underwent multiplane transesophageal echocardiography and blood cultures. Cerebral, thoracoabdominal computed tomographic scan was performed in almost all patients (95%). All patients with S. bovis endocarditis underwent colonoscopy. Incidence of S. bovis endocarditis in our sample was 19%. Patients with S. bovis endocarditis were older than other groups. Multiple valve involvement, native valves, and large vegetations (>10 mm) were more frequent in patients with S. bovis. There was a significantly higher occurrence of embolism in the S. bovis group. Splenic embolism and multiple embolisms were significantly more frequent in patients with S. bovis. Gastrointestinal lesions, anemia, and spondylitis were observed more frequently with S. bovis endocarditis. In addition to the requirement for gastrointestinal examination for S. bovis endocarditis, our study underlines the need for systematic screening for vertebral and splenic localizations, and suggests the use of early surgery to prevent the high risk of embolism in these patients.

Echocardiography predicts embolic events in infective endocarditis

OBJECTIVES

The aim of our study was to assess the value of transesophageal echocardiography (TEE) in predicting embolic events (EEs) in a large group of patients with definite endocarditis according to the Duke criteria, including silent embolism.

BACKGROUND

The value of echocardiography in predicting embolism in patients with endocarditis remains controversial. Some studies reported an increased risk of embolism in patients with large and mobile vegetations, whereas other studies failed to demonstrate such a relationship.

METHODS

Multiplane transesophageal echocardiograms of 178 consecutive patients with definite infective endocarditis (IE) were analyzed. The incidence of embolism was compared with the echocardiographic characteristics (localization, size and mobility) of the vegetations. To detect silent embolism, cerebral and thoraco-abdominal scans were performed in 95% of patients.

RESULTS

Among 178 patients, 66 (37%) had one or more EEs. There was no difference between patients with and without embolism in terms of age, gender and left valve involved. On univariate analysis, Staphylococcus infection, right-side valve endocarditis and vegetation length and mobility were significantly related to EEs. A significant higher incidence of embolism was present in patients with vegetation length >10 mm (60%, p < 0.001) and in patients with mobile vegetations (62%, p < 0.001). Embolism was particularly frequent among 30 patients with both severely mobile and large vegetations (> 15 mm) (83%, p < 0.001). On multivariate analysis, the only predictors of embolism were vegetation length (p = 0.03) and mobility (p = 0.01).

CONCLUSIONS

Our study shows that the presence of vegetations on TEE is predictive of embolism and that the morphologic characteristics of vegetations are helpful in predicting EEs in both mitral and aortic valve IE. It also suggests that early operation may be recommended in patients with vegetations > 15 mm and high mobility, irrespective of the degree of valve destruction, heart failure and response to antibiotic therapy.

[Validation of quantitative parameters of paraprosthetic mitral valve regurgitation of the zone of convergence by transthoracic echocardiography]

The study of the convergence zone by echocardiography is a validated method of quantification of native valve mitral regurgitation. However, there is little data concerning its applications to paraprosthetic mitral regurgitation. The aim of this study was to evaluate the method in this indication. Thirty consecutive patients (21 mechanical and 9 bioprostheses) with paraprosthetic mitral regurgitation quantified by transoesophageal echocardiography were included: 4 mild, 13 moderate and 13 severe. The regurgitant volume RV) and the regurgitant surface area (RSA) were calculated by the following formulae: RV = 2 pi.r2.Va.t.alpha/180 and RSA = RV/VTI (r: mid systolic radius of the convergence zone, Va: aliasing velocity, t: regurgitation time, alpha/180: the angular correction due to parietal stress, VTI: velocity time integral of the regurgitant flow). The feasibility of the calculation of the RV and RSA was 93 and 63% respectively. There was a statistically significant correlation between the RV and transoesophageal echocardiography (r: 0.85, p < 0.001), between RSA and transoesophageal echocardiography (r: 0.67, p < 0.05) and between RV and RSA (r: 0.95, p < 0.001). When severe paraprosthetic regurgitation was defined by a RV greater than 60 ml and RSA greater than 40 mm2, the concordance between RV, RSA and transoesophageal echocardiography was 75% and 74% respectively. Therefore, the study of the convergence zone provides an accurate evaluation of paraprosthetic mitral regurgitation by transthoracic echocardiography.

Interelectrode (Accufix) lead fracture

An interelectrode fracture was diagnosed 7 years after the implantation of an Accufix lead. The lead body separated from the tip with the helix screwed into the atrial wall. The retention wire was intact and may have contributed to the lead rupture.

[Heart perforation following transvenous implantation of a cardiac pacemaker]

OBJECTIVES

We studied the incidence, clinical signs and severity of heart perforations occurring after transvenous pacemaker implantation.

PATIENTS AND METHODS

A series of 16 consecutive cases of heart perforation observed in one cardiac pacing unit from 1989 to 1998 were reviewed.

RESULTS

Heart perforation occurred after implantation in 9 cases; the verall incidence for all lead implantation was 0.57%. The ventricle was perforated in 6 cases, the atrium in 1, and an undetermined site in 2 cases. Active fixation was involved in 5 cases, passive fixation in 4. A bipolar lead was used in 7 cases and a unipolar lead in 2. Heart perforation occurred after prior external stimulation in 7 cases, including one case with tamponnade requiring emergency pericardial drainage after implantation. Repositioning the lead in the ventricle was sufficient in 6 cases and a thoracotomy for an atrial wound was performed in 1 case. Difficulties in right ventricular catheterism due to kyphoscoliosis in elderly subjects was found to be a risk factor.

CONCLUSION

Heart perforation following transvenous pacemaker implantation is an exceptional complication with currently used material. Tamponnade is extremely rare. Besides verifying the mechanical performance of the leads, prevention requires a rigorous protocol for catheterism and wall fixation.

[Criteria of localization of the bundle of Kent]

The high success rate (> 90%) of radiofrequency ablation of accessory pathways is related to accurate mapping. This determines the site of the accessory pathway and the best target for ablation with the object of reducing the number of applications and the associated morbidity. Analysis of the surface ECG is the first step of localisation of a Kent bundle. Different algorithms may be used based on the correlation between the polarity of the delta wave, of the QRS and the site of the accessory pathway confirmed at surgery or during radiofrequency ablation procedures. Some of the recent algorithms allow localisation of certain postero-septal or sub-epicardial pathways, the ablation of which can only be accomplished via the coronary sinus or one of its branches, or in an abnormally dilated coronary sinus, the so-called diverticulum. A relatively accurate localisation of the accessory pathway from the surface ECG reduces the duration of an ablation procedure and may economise the need for left-sided catheterisation. However, the endocavitary electrogrammes determine the precise target of ablation whether this be the ventricular or atrial pole of the bundle of Kent. The association of the criteria obtained by bipolar and unipolar recordings in sinus rhythm, during pacing or reentrant tachycardia enables accurate localisation in the majority of cases. Ablation of some pathways may be more complex because of their site or the presence of associated congenital or acquired cardiac disease which alters the anatomical or electrical markers. In these cases, the electrical criteria, especially those of the surface ECG may be erroneous and non invasive investigations such as Doppler echocardiography, isotopic ventriculography with phase analysis are most valuable with a positive predictive value of over 90%.

[Homocysteine and coronary events in coronary disease patients]

The objective of this study was to determine the prognostic value of serum homocysteine levels in patients with coronary heart disease. Homocysteine was assayed in 76 coronary patients with a mean age of 59.2 years hospitalized for myocardial ischaemia or myocardial infarction. Percutaneous transluminal angioplasty was performed in 47 (70%) of these patients during this hospitalization. The mean follow-up for these patients was 22 months (range: 11 to 67 months). In these patients, serum homocysteine levels were not correlated with the usual risk factors of coronary heart disease (age, sex, treated hypercholesterolaemia, smoking, diabetes) except for hypertension. It was strongly correlated with serum creatinine (R = 0.61; p = 0.0001). Eleven patients presented a major event during follow-up (8 deaths, 1 nonfatal myocardial infarction, 1 cardiac transplantation) and 16 underwent a revascularization procedure. The blood homocysteine level does not have any prognostic value for any coronary events. However, it is higher in patients who develop a major event than in those which do not (15.8 +/- 4 mumol/l versus 11.5 +/- 6.6 mumol/l, p = 0.05). Using multivariate analysis, taking into account age, serum creatinine and serum homocysteine, only serum homocysteine was predictive of major event-free survival (p = 0.02).

Diagnostic value of the preoperative sestamibi scan in intraoperative localization of parathyroid adenomas: a case study

A retrospective chart review of 43 patients who underwent technetium 99m (Tc-99m) sestamibi scans from June 1995 to January 1997 was performed. Only those who underwent subsequent parathyroid exploration with excision were included in the study. Twenty subjects (13 women and seven men) were included in the study. Ages ranged from 21 to 84 years (mean, 58 years). All patients had laboratory values and clinical findings consistent with primary hyperparathyroidism. Two patients had preoperative magnetic resonance imaging (MRI) scans (one patient with recurrent disease), and one had a preoperative computed tomography (CT) scan. The remaining patients had the sestamibi scan as the only preoperative localization study. There were 18 pathologic diagnoses of parathyroid adenoma and two of parathyroid hyperplasia. Sestamibi failed to correctly identify the location of the parathyroid lesion in two cases. In 18 cases the preoperative sestamibi scan correctly localized the lesion, a predictive value of 90%. We conclude that the Tc-99m sestamibi scan is an accurate preoperative tool that can be used as a single modality to localize parathyroid adenomas.

[ECG anomalies and axis deviations in heart transplant recipients: MRI studies]

The electrocardiogram is often abnormal after orthotopic cardiac transplantation. This study was conducted in order to evaluate the frequency of these abnormalities in a population of 29 patients transplanted according to the conventional mode or the total mode. We also investigated the correlation between these abnormalities and the presence of left ventricular hypertrophy or deviation of the left ventricular long axis. The left ventricular mass was measured by TM echocardiography. The position of the left ventricular long axis was determined by MR on a ultrarapid sequence. The ECG was normal in 5 patients. The abnormalities revealed in the other 24 patients were: an rSr' or rsr' appearance in V1 with a QRS complex less than 0.12 sec in 11 patients, complete right block in 1 patients, repolarization abnormalities (apart from those associated with branch blocks) in 8 patients, left axis deviation of the QRS in 5 patients, a biphasic P wave in V1 with a Morris index greater than 4 mV.sec in 5 patients, and double atrial activity in 3 patients. These abnormalities were observed regardless of the type of transplantation, with the exception of double atrial activity which was only observed in the group of patients undergoing conventional transplantation. On average, the long axis of the left ventricle was more horizontal and deviated to the left compared to age- and sex-matched controls. All patients with left axis deviation of the QRS had left ventricular hypertrophy versus 13 of the 24 patients without QRS axis deviation and abnormalities of position of the anatomical left ventricular long axis. Our results therefore suggest that the frequent presence of right branch block in heart transplant recipients is due to factors other than the position of the heart in the thorax, for example right ventricular hypertrophy.

[Quantification of mitral regurgitation by cine-MRI. Comparison with transesophageal echocardiography in 45 patients]

Cine-MRI demonstrates the presence of mitral regurgitation by a signal void. This study was undertaken to assess the value of this method for quantification of mitral regurgitation in a population not excluding either patients with mitral valve prostheses or those with atrial fibrillation. The subjects included had a mean age of 59 years and were referred for transoesophageal echocardiography, either for assessment of valvular heart disease (38 patients), or for detection of atrial thrombosis before external electrical cardioversion (7 patients). Eight patients had mitral valve prostheses and 19 were in atrial fibrillation. Cine-MRI was performed within 12 days of the transoesophageal echocardiography study with a 1.5 tesla magnet, using a sequence of gradient echo in 3 parallel planes in the 4 chamber view. The regurgitation was quantified by MRI from the extension of the signal void in the left atrium. The transoesophageal Doppler echocardiographic criteria were the width of the regurgitant jet at its origin, the intensity of the regurgitation signal recorded by continuous wave Doppler and the extension of the jet within the left atrium. The quantification by degrees 1 to 4 did not differ by more than 1 degree between the 2 techniques in 43 of the 45 patients. Out of 4 left atrial thrombus detected by transoesophageal echocardiography, only 1 was visible by MRI. The authors concluded that quantification of mitral regurgitation by cine-MRI provides similar results to those obtained by transoesophageal echocardiography and that the correlation remains valid in cases of atrial fibrillation. However, Doppler echocardiography provides further valuable information for the clinician.

[Abnormal origin of the left coronary artery from the pulmonary artery. Diagnostic contribution of ultrasonographic technique]

We report a case of abnormal origin of the left coronary artery from the pulmonary artery trunk. The original features of this case were its discovery in a young pregnant woman, the normality of basal left ventricular function and the electrocardiogram, the diagnosis by transoesophaegeal echocardiography, and the demonstration of severe myocardial ischaemia by stress echocardiography.

[Value of echocardiography in the study of aortic valve homografts and autografts]

Although increasingly used, the echocardiographic parameters of aortic valve homografts and autografts have not been extensively investigated. The aim of this study was to assess the value of transthoracic (TTE) and transoesophageal (TOE) echocardiography in the preoperative assessment of these patients, especially with regards to prediction of homograft size and to describe the normal and pathological echocardiographic appearances of this type of prosthesis. Thirty-seven consecutive patients were studied. Before surgery, the diameter of the aortic ring (24.1 +/- 3 mm), correlated well with the value measured by the surgeon (24.4 +/- 2 mm; r = 0.9), but in 2 cases, this measurement was impossible and in 3 cases inaccurate, the difference between the 2 measurements being greater than 2 mm. It was possible to measure the aortic ring diameter in all cases by TOE. After surgery, TTE showed normal function of 33 of the 37 prosthetic valves with minimal or no obstruction (mean gradient 5.9 +/- 4 mmHg, aortic surface area = 2.8 +/- 0.5 cm2) with no significant difference between the homografts and autografts. Better visualisation of the homograft leaflets was possible by TOE and detected minimal central regurgition in 16 (84%) of the homografts examined, the persistence of an annular abscess in 2 patients and a minimal aorto-left atrial fistula in 1 patient. In conclusion. TTE coupled with Doppler examination is usually adequate for preoperative selection of the homografts and haemodynamic evaluation and follow-up of these patients. TOE should be performed preoperatively in patients with unsatisfactory TTE studies but is mainly useful for preoperative evaluation and postoperative follow-up of patients operated for aortic endocarditis with paravalvula abscess.

[Non bacterial thrombotic endocarditis (marantic endocarditis). Apropos of a case and value of transoesophageal echocardiography]

Marantic or non-bacterial thrombotic endocarditis is a common complication of terminal malignancy, usually discovered at autopsy. The authors report a case of marantic endocarditis as a presenting sign of pancreatic carcinoma in which the diagnosis was made ante-mortem by transoesophageal echocardiography.

Body surface potential distributions during idiopathic ventricular tachycardia

BACKGROUND

The purpose of this report is to describe the body surface potential maps (BSPMs) during idiopathic ventricular tachycardia (VT) and to determine what differences exist between different idiopathic VT morphologies.

METHODS AND RESULTS

We performed BSPMs during VT on 12 consecutive patients (3 women and 9 men; mean age, 42 +/- 13 years) presenting symptomatic idiopathic VT referred to our institution for electrophysiological study. Basal ECG, chest radiograph, and echocardiogram were normal in all patients. Clinical tachycardia showed left bundle branch block pattern (LBBB) in 9 patients, with sustained VT in 5 and nonsustained VT in 4, and right bundle branch block pattern (RBBB) in 3 with sustained VT. We found a unique pattern of BSPMs in each of the 9 patients during idiopathic LBBB VT configuration, whether sustained or nonsustained VT. This pattern appeared at the onset of the QRS and remained stable during the whole QRS complex. The area of minimal potential located in the upper anterior part of the torso was compatible with an origin of VT in the right ventricular outflow tract, as confirmed in 5 patients by successful radiofrequency ablation. We found an evolving pattern with two phases in each of the three RBBB VTs. The electrical axis during the initial part of the QRS could correspond to an endocardial-epicardial vector. The second phase, with a high voltage and area of minimal potential located in the inferior and anterior part of the torso, was compatible with a left ventricular apical origin that was confirmed by epicardial and endocardial mapping during cryosurgery in 1 patient. For all the VTs, the QRS isoarea maps showed the same pattern as the second phase of the QRS.

CONCLUSIONS

Two different BSPM patterns were found. All LBBB VTs had the same stable pattern corresponding to an infundibular origin. All RBBB VTs had an evolving pattern that stabilized in the second part of the QRS complex corresponding to an apical origin.

[Primary ventricular fibrillation and early recurrence: apropos of a case of association of right bundle branch block and persistent ST segment elevation]

The authors report the case of a 36 year old man who presented with an early recurrence of primary ventricular fibrillation. The initial investigations were normal apart from the finding of complete right bundle branch block with persistent ST segment elevation in the right precordial leads. The recurrence was observed 6 weeks after the initial diagnosis which led to the implantation of an automatic defibrillator. This clinical case is similar to a syndrome recently described of sudden death without obvious cardiac disease but with right bundle branch block and ST segment elevation.

Radiofrequency catheter ablation of an accessory pathway in a young man with dextroversion

We report an observation of a radiofrequency catheter ablation of an accessory pathway (AP) in a patient with Wolff-Parkinson-White syndrome (WPW) and dextroversion. Atrioventricular rings were mapped by the ablation catheter to locate the shortest local atrioventricular conduction time in sinus rhythm and ventriculoatrial conduction time during orthodromic tachycardia or ventricular pacing. Successful ablation confirmed a right posteroseptal AP localization. Thus, the electrocardiographic modifications due to an AP in this location in the presence of dextroversion were defined.

[Slow ventricular tachycardia caused by naftidrofuryl overdose (naftidrofuryl and ventricular tachycardia)]

Treatment with intravenous naftidrofuryl may be complicated by ventricular arrhythmias. A case of slow ventricular tachycardia occurring in a 65-year-old man with a dilated cardiomyopathy following an accidental overdose of naftidrofuryl (2 x 200 mg ampules in 250 ml of 5% glucose solution in 2 hours) prescribed for complicated arterial disease of the lower limbs is reported. This sustained ventricular tachycardia converted spontaneously after several hours. This case emphasises the risk of arrhythmogenic effects of this drug and indicates the need for careful monitoring when it is used intravenously in patients with underlying heart disease.

[Cardiac mass, ventricular relaxation parameters and their correlation with blood pressure during rest and ambulatory monitoring]

A resting blood pressure (Dynamap, 8AM-8PM, one recording every 15 minutes) has been recorded among 60 patients; mean age: 51 +/- 14 years (24 females, 36 males; 3 normotensive and 57 hypertensive WHO) and a echocardiogram TM and two-dimensional with doppler in order to measure the interventricular septum thickness, Left Ventricular Posterior Wall Thickness and the left Ventricular Internal diameter with which we can calculate the myocardial mass (MM, Devereux formula) and the myocardial mass index using the body surface. Furthermore ventricular relaxation has been studied (A/E, PHT) by using doppler echocardiogram. During the same week an ambulatory blood pressure (Nippon Colin 8AM-8PM one reading every 15 minutes) has been recorded. The blood variables are the mean of the recording, systolic, diastolic, mean. We have confirmed the conclusion between blood pressure and left ventricular mass by using resting and ambulatory blood pressure recordings. But it does not exist any significant difference within we compare the correlations coefficients (Hotteling's Test with Williams modification) obtained with two devices. In revenge this difference exists with ventricular relaxation index A/E to MBP: mMBPr = 0.51, mMBPa = 0.34 (p less than 0.05), and PHT to MBP: mMBPr = 0.49, mMBPa = 0.31, (p less than 0.05) and to the SBP: mSBPr = 0.54, mSBPa = 0.35, (p less than 0.05).

CONCLUSION

the relationship between blood pressure and myocardial mass and by, the heart effect from hypertension can be studied by using in any case resting and ambulatory blood pressure recordings. This will confirm the hypothesis in which the blood pressure recordings multiplication is more important than the way of recording it.(ABSTRACT TRUNCATED AT 250 WORDS)