(1/1634) Frequency and long term follow up of valvar insufficiency caused by retrograde aortic radiofrequency catheter ablation procedures.

OBJECTIVE: To assess the frequency of valvar complications caused by left sided radiofrequency catheter ablation using the retrograde aortic technique. METHODS: 179 patients (118 male) with a mean (SD) age of 43 (17) years underwent 216 procedures at one centre. The target of the ablation was an accessory atrioventricular pathway in 144 patients, the atrioventricular junction in 29 patients, and a ventricular tachycardia in six patients. In 25 patients structural heart disease was identified before the procedure (ischaemic heart disease 10, cardiomyopathy nine, valvar three, other three). Echo/Doppler examinations were performed the day before the procedure and within 24 hours postablation; the investigations were all reviewed by the same investigator. Patients with identified valvar injury caused by the procedure were followed for 42 (7) months. RESULTS: Valvar injury caused by the ablation procedure was identified in four young (age 30 (8) years), otherwise healthy patients with left lateral atrioventricular accessory pathways. Mild mitral insufficiency with a central regurgitation jet was detected in two patients and remained unchanged at follow up. Mild aortic insufficiency was detected in another two patients. In one of these the regurgitation jet was central and remained unchanged at follow up. In one patient the regurgitation jet was located between the non-coronary and left cusps in relation to a loosely attached structure. Both the structure and the valvar regurgitation disappeared during follow up. No clinical complications occurred in any of the patients during follow up. CONCLUSION: In this study, the frequency of valvar complications after left sided radiofrequency catheter ablation using the retrograde aortic technique was 1.9%.  (+info)

(2/1634) Chordal force distribution determines systolic mitral leaflet configuration and severity of functional mitral regurgitation.

OBJECTIVES: The purpose of this study was to investigate the impact of the chordae tendineae force distribution on systolic mitral leaflet geometry and mitral valve competence in vitro. BACKGROUND: Functional mitral regurgitation is caused by changes in several elements of the valve apparatus. Interaction among these have to comply with the chordal force distribution defined by the chordal coapting forces (F(c)) created by the transmitral pressure difference, which close the leaflets and the chordal tethering forces (FT) pulling the leaflets apart. METHODS: Porcine mitral valves (n = 5) were mounted in a left ventricular model where leading edge chordal forces measured by dedicated miniature force transducers were controlled by changing left ventricular pressure and papillary muscle position. Chordae geometry and occlusional leaflet area (OLA) needed to cover the leaflet orifice for a given leaflet configuration were determined by two-dimensional echo and reconstructed three-dimensionally. Occlusional leaflet area was used as expression for incomplete leaflet coaptation. Regurgitant fraction (RF) was measured with an electromagnetic flowmeter. RESULTS: Mixed procedure statistics revealed a linear correlation between the sum of the chordal net forces, sigma[Fc - FT]S, and OLA with regression coefficient (minimum - maximum) beta = -115 to -65 [mm2/N]; p < 0.001 and RF (beta = -0.06 to -0.01 [%/N]; p < 0.001). Increasing FT by papillary muscle malalignment restricted leaflet mobility, resulting in a tented leaflet configuration due to an apical and posterior shift of the coaptation line. Anterior leaflet coapting forces increased due to mitral leaflet remodeling, which generated a nonuniform regurgitant orifice area. CONCLUSIONS: Altered chordal force distribution caused functional mitral regurgitation based on tented leaflet configuration as observed clinically.  (+info)

(3/1634) Effects of permanent dual-chamber pacing on mitral regurgitation in hypertrophic obstructive cardiomyopathy.

AIMS: To assess the effects of chronic dual-chamber pacing on mitral regurgitation in hypertrophic obstructive cardiomyopathy. METHODS AND RESULTS: Twenty-three patients with hypertrophic obstructive cardiomyopathy and mitral regurgitation. treated with DDD pacing for 16 +/- 14 months, were included in the study. Mitral regurgitation was assessed by Doppler-echocardiography using semi-quantitative analysis (grades I-IV) and by measuring the maximum regurgitant jet area/left atrial area ratio. At the end of follow-up, DDD pacing reduced the outflow gradient from 93 +/- 37 mmHg to 31 +/- 30 mmHg (P<0.0001). Nine of the 14 patients who initially had > or =grade II mitral regurgitation improved by at least one grade, two of them exhibiting dramatic improvement (from grade IV and III to grade I). The regurgitant jet area/left atrial area ratio was reduced with DDD pacing from 20 +/- 13% to 11 +/- 6% (P<0.0001). Patients who had significant mitral regurgitation despite pacing were those whose outflow gradient remained high or those with mitral valve organic abnormalities (mitral annulus calcification or mitral valve prolapse). In the absence of organic abnormalities other than leaflet elongation, there was a significant correlation between the gradient value achieved with DDD pacing and the extent of mitral regurgitation (P<0.05). CONCLUSION: In the absence of organic mitral valve abnormalities, DDD pacing reduces in parallel mitral regurgitation and left ventricular outflow gradient. In such patients therefore, significant mitral regurgitation is not a contraindication to pacing.  (+info)

(4/1634) Symptomatic mitral myxomatous transformation in the elderly.

The clinical and pathological features of four patients with intractable heart failure, due to myxomatous change in the mitral valve, are described. It is suggested that this change may represent a response of ageing connective tissue to mechanical stress.  (+info)

(5/1634) An evaluation of left ventricular function after surgery for pure mitral regurgitation using dobutamine-stress echocardiography--should the mitral complex be preserved?

To evaluate the importance of preserving the mitral complex, clinical outcomes and postoperative left ventricular (LV) functions of 175 patients with pure mitral regurgitation (MR) were analyzed. They were divided into three groups; patients who had conventional mitral valve replacement (cMVR; n = 47), posterior mitral leaflet preserved MVR (pMVR; n = 66) or mitral valvuloplasty (MVP; n = 62). There was no operative death or hospital death in this study. The actuarial survival rate was 85.2% in cMVR, 78.5% in pMVR, and 84.7% in MVP at 10 years after operation. The actuarial freedom from reoperation 10 years postoperatively was 100% in cMVR, 97.9% in pMVR, 85.8% in MVP. The actuarial freedom from thromboembolism (TE) at 10 years was 92.2% in cMVR, 87.1% in pMVR, 93.5% in MVP. Freedom from all types of events including non-cardiac death was 78.3% in cMVR, 64.8% in pMVR, 65.3% in MVP at 10 years, respectively. Pre- and postoperative LV function was evaluated using echocardiography. Patients with MVP had better LV performance than those with MVR. However, there was no significant difference between the cMVR and pMVR groups. For further estimation of postoperative LV function, dobutamine-stress echocardiography (DSE) was performed. The results of DSE revealed that the LV contractility in MVP was obviously better than those in MVR groups especially in systole. The change in ejection fraction (EF) from baseline to peak dobutamine stress in the pMVR group was significantly greater than in cMVR. This study supports the concept that the preservation of continuity between the mitral annulus and papillary muscle plays an important role in clinical outcome and postoperative LV function. In conclusion, MVP should be a first choice as an operative method for pure MR when technically feasible. When it is impossible to perform MVP, pMVR, not cMVR, should be the next choice. This study suggests that preservation of papillary muscle-mitral annular continuity during mitral valve surgery for pure MR is beneficial to LV systolic function.  (+info)

(6/1634) Three-dimensional color Doppler: a clinical study in patients with mitral regurgitation.

OBJECTIVES: The purpose of this study was to assess the clinical feasibility of three-dimensional (3D) reconstruction of color Doppler signals in patients with mitral regurgitation. BACKGROUND: Two-dimensional (2D) color Doppler has limited value in visualizing and quantifying asymmetric mitral regurgitation. Clinical studies on 3D reconstruction of Doppler signals in original color coding have not yet been performed in patients. We have developed a new procedure for 3D reconstruction of color Doppler. METHODS: We studied 58 patients by transesophageal 3D echocardiography. The jet area was assessed by planimetry and the jet volumes by 3D Doppler. The regurgitant fractions, the volumes, and the angiographic degree of mitral regurgitation were assessed in 28 patients with central jets and compared with those of 30 patients with eccentric jets. RESULTS: In all patients, jet areas and jet volumes significantly correlated with the angiographic grading (r = 0.73 and r = 0.90), the regurgitant fraction (r = 0.68 and r = 0.80) and the regurgitant volume (r = 0.66 and r = 0.90). In patients with central jets, significant correlations were found between jet area and angiography (r = 0.86), regurgitant fraction (r = 0.64) and regurgitant volume (r = 0.78). No significant correlations were found between jet area and angiography (r = 0.53), regurgitant fraction (r = 0.52) and regurgitant volume (r = 0.53) in the group of patients with eccentric jets. In contrast, jet volumes significantly correlated with angiography (r = 0.90), regurgitant fraction (r = 0.75) and regurgitant volume (r = 0.88) in the group of patients with eccentric jets. CONCLUSIONS: Three-dimensional Doppler revealed new images of the complex jet geometry. In addition, jet volumes, assessed by an automated voxel count, independent of manual planimetry or subjective estimation, showed that 3D Doppler is also capable of quantifying asymmetric jets.  (+info)

(7/1634) Three-dimensional Doppler. Techniques and clinical applications.

AIMS: Colour Doppler is the most widely used technique for assessing valve disease, but eccentric regurgitant jets cannot be visualized and measured by conventional 2D techniques. We have developed a new procedure for three-dimensional (3D) reconstruction of colour Doppler signals. METHODS AND RESULTS: Fifty patients with mitral regurgitation underwent transoesophageal echocardiography and 3D acquisition. The severity of mitral regurgitation was assessed by angiography and the regurgitant volumes were measured by pulsed Doppler. The jet areas were calculated by planimetry from conventional colour Doppler; the jet volumes were obtained by 3D Doppler. A higher degree of mitral regurgitation was found in the patients with eccentric jets. While jet areas showed poor correlation with regurgitant volumes (r = 0.61), jet volumes correlated significantly with regurgitant volumes (r = 0.93; P < 0.001). While jet areas failed to identify patients with different grades of regurgitation, jet volumes could so discriminate. CONCLUSIONS: 3D Doppler revealed new patterns of regurgitant flow and allowed a more accurate semiquantitative assessment of complex asymmetrical regurgitant jets. Three-dimensional colour Doppler has a great potential for becoming a reference method for the assessment of patients with heart valve disease.  (+info)

(8/1634) The Mitral Regurgitation Index: an echocardiographic guide to severity.

OBJECTIVES: The purpose of this study was to develop a semiquantitative index of mitral regurgitation severity suitable for use in daily clinical practice and research. BACKGROUND: There is no simple method for quantification of mitral regurgitation (MR). The MR Index is a semiquantitative guide to MR severity. The MR Index is a composite of six echocardiographic variables: color Doppler regurgitant jet penetration and proximal isovelocity surface area, continuous wave Doppler characteristics of the regurgitant jet and tricuspid regurgitant jet-derived pulmonary artery pressure, pulse wave Doppler pulmonary venous flow pattern and two-dimensional echocardiographic estimation of left atrial size. METHODS: Consecutive patients (n = 103) with varying grades of MR, seen in the Adult Echocardiography Laboratory at UCSF, were analyzed retrospectively. All patients were evaluated for the six variables, each variable being scored on a four point scale from 0 to 3. The reference standards for MR were qualitative echocardiographic evaluation by an expert and quantitation of regurgitant fraction using two-dimensional and Doppler echocardiography. A subgroup of patients with low ejection fraction (EF < 50%) were also analyzed. RESULTS: The MR Index increased in proportion to MR severity with a significant difference among the three grades in both normal and low EF groups (F = 130 and F = 42, respectively, p < 0.0001). The MR Index correlated with regurgitant fraction (r = 0.76, p < 0.0001). An MR Index > or =2.2 identified 26/29 patients with severe MR (sensitivity = 90%, specificity = 88%, PPV = 79%). No patient with severe MR had an MR Index <1.8 and no patient with mild MR had an MR Index >1.7. CONCLUSIONS: The MR Index is a simple semiquantitative estimate of MR severity, which seems to be useful in evaluating MR in patients with a low EF.  (+info)