Sudden death in mitral regurgitation due to flail leaflet

OBJECTIVES

We sought to assess the incidence and determinants of sudden death (SUD) in mitral regurgitation due to flail leaflet (MR-FL).

BACKGROUND

Sudden death is a catastrophic complication of MR-FL. Its incidence and predictability are undefined.

METHODS

The occurrence of SUD was analyzed in 348 patients (age 67 ± 12 years) with MR-FL diagnosed echocardiographically from 1980 through 1994.

RESULTS

During a mean follow-up of 48 ± 41 months, 99 deaths occurred under medical treatment. Sudden death occurred in 25 patients, three of whom were resuscitated. The sudden death rates at five and 10 years were 8.6 ± 2% and 18.8 ± 4%, respectively, and the linearized rate was 1.8% per year. By multivariate analysis, the independent baseline predictors of SUD were New York Heart Association (NYHA) functional class (p = 0.006), ejection fraction (p = 0.0001) and atrial fibrillation (p = 0.059). The yearly linearized rate of sudden death was 1% in patients in functional class I, 3.1% in class II and 7.8% in classes III and IV. However, of 25 patients who had SUD, at baseline, 10 (40%) were in functional class I, 9 (36%) were in class II and only 6 (24%) in class III or IV. In five patients (20%), no evidence of risk factors developed until SUD. In patients with an ejection fraction ≥60% and sinus rhythm, the linearized rate of SUD was not different in functional classes I and II (0.8% per year). Surgical correction of MR (n = 186) was independently associated with a reduced incidence of SUD (adjusted hazard ratio [95% confidence interval] 0.29 [0.11 to 0.72], p = 0.007).

CONCLUSIONS

Sudden death is relatively common in patients with MR-FL who are conservatively managed. Patients with severe symptoms, atrial fibrillation and reduced systolic function are at higher risk, but notable rates of SUD have been observed without these risk factors. Correction of MR appears to be associated with a reduced incidence of SUD, warranting early consideration of surgical repair.     

Color Doppler echocardiographic evaluation of patients with a flail mitral leaflet

Chordal rupture with a subsequent flail mitral valve leaflet is now the most common cause of pure mitral regurgitation. To describe the Doppler color flow findings in flail mitral leaflet and the determinants of these findings, Doppler color flow mapping and conventional Doppler echocardiography were performed in 31 consecutive patients presenting with a flail mitral leaflet. In the 23 patients with a posterior flail leaflet, a distinctive highly eccentric and turbulent jet directed toward the posterior wall of the aorta was noted. In the eight patients with an anterior flail leaflet, a jet directed toward the posterolateral left atrial wall was noted. Maximal regurgitant jet area was significantly larger in patients with a flail anterior leaflet (13.1 +/- 3.0 cm2) than in those with a flail posterior leaflet (5.8 +/- 3.0 cm2, p = 0.0001). Maximal jet area to left atrial ratio was also significantly higher in those with a flail anterior leaflet (0.56 +/- 0.16) than in those with a flail posterior leaflet (0.27 +/- 0.17, p = 0.0006). When systolic left atrial velocities encoded as red were incorporated into the maximal jet area measurement, 7 of the 8 patients with an anterior flail leaflet had a jet area greater than 8 cm2, consistent with severe mitral regurgitation, compared with 13 of the 23 patients with a flail posterior leaflet. There was no correlation between jet area or jet area to left atrial ratio and any hemodynamic variable. Patients with acute mitral regurgitation exhibited a trend toward smaller jet areas, but this did not reach statistical significance. Regurgitant fraction calculated from pulsed Doppler recording of mitral and aortic flow was consistent with moderately severe or severe mitral regurgitation in all cases and averaged 70%. Thus, patients with a flail mitral valve leaflet have distinctive Doppler color flow findings. A highly eccentric and turbulent jet directed posteriorly to the aorta may contribute to a systematic underestimation of severe mitral regurgitation by conventional Doppler color flow criteria. The use of pulsed Doppler ultrasound to calculate regurgitant fraction in patients with a flail mitral valve leaflet may be helpful in reliably assessing the degree of mitral regurgitation.     

Double orifice mitral valve with flail leaflet: a transoesophageal echocardiographic examination.

We describe a case of double orifice mitral valve and a flail leaflet in a 54-year-old man. This rare congenital abnormality was disclosed through the discovery of a murmur. The transoesophageal approach clearly showed two approximately equal orifices with multiple papillary muscles. Colour Doppler echocardiography showed a moderate mitral regurgitation due to the prolapse of the posterior leaflet of the anteromedial orifice. No other abnormality was associated. Transoesophageal echocardiography is useful to analyse as well the anatomy as the functional aspect of the mitral apparatus in this particular case of congenital disease.     

Natural history of the flail mitral leaflet syndrome: a serial 2-dimensional echocardiographic study

The syndrome of a flail mitral leaflet results in acute mitral regurgitation (MR). Twenty-nine patients with a flail mitral leaflet had serial 2-dimensional echocardiographic (2-D echo) examinations. Left ventricular (LV) and left atrial (LA) volumes and ejection fraction (EF) were obtained using a computerized light-pen system. Fifteen patients with the 2-D echo criteria of a flail mitral leaflet were treated medically and followed for a mean of 19 months. Eleven patients did not undergo surgery (Group IA). Four patients initially were treated medically, but ultimately required surgery (Group IB). On initial examination there was no difference in volumes and EF between these 2 groups. On follow-up, Group IA patients remained in New York Heart Association class I or II. The LV end-diastolic volume increased in the Group IA patients from 164 ± 27 to 203 ± 54 ml (p <0.01); LV ejection fraction tended to increase (from 51 ± 5 to 56 ± 8, p <0.06). On follow-up, Group IB patients had larger LA and LV volumes than Group IA patients.Fourteen patients were initially treated surgically (Group II). All but 1 were in New York Heart Association Class III or IV. On Initial examination LVEF was lower than in Group IA patients (51 ± 5 versus 43 ± 7, p = 0.05), but there was no difference in LV or LA volumes. On follow-up, a mean of 19 months after surgery, LVEF and LA volumes decreased.We conclude that a subset of patients with a flail mitral leaflet may be followed clinically without deterioration in LV function. Initial LVEF and hemodynamics are reasonably normal. Because increasing LV and LA volumes and changing clinical status are not a function of time, frequent 2-D echo and clinical evaluations are warranted in these patients. After mitral valve replacement, LVEF decreases without a significant change in LV volume.     

Flail mitral and tricuspid valves due to myxomatous disease.

Myxomatous disease generally affects mitral valve. However, tricuspid valves also can be involved in 20% of the myxomatous mitral valve disease. Valve prolapse, elongation of chordae and chordae rupture are generally seen complications of the myxomatous disease. There are some reports about severe tricuspid regurgitation due to tricuspid valve prolapse and elongated chordae, but no tricuspid and mitral chordae ruptures in the same patient due to myxomatous disease have been reported. In this case tricuspid chordae rupture accompanied to mitral chordae rupture is discussed.     

Severe mitral regurgitation due to perforation of the mitral anterior leaflet

We present a case of a 75-year-old male with a worsening dyspneaduring the last month. Transthoracic echocardiography revealeda severe mitral regurgitation. Transesophageal echocardiographywas evident of a 6 mm defect of the mitral anterior leafletat the region of the anteromedial A1 and medial A2 scallopsprobably due to perforation, which caused a significant regurgitantjet as documented by the presence of a convergence flow overthe ‘hole’. As the patient had a prolonged feverof undetermined origin one and a half months ago, perforationof the mitral anterior leaflet must at least be considered tobe of an infective origin.     

Feasibility of myxomatous mitral valve repair using direct leaflet and chordal radiofrequency ablation

Objective: Minimally invasive repair of mitral valve prolapse (MVP) causing severe mitral regurgitation (MR) should reduce MR and have chronic durability. Our ex vivo, acute in vivo, and chronic in vivo studies suggest that direct application of radiofrequency ablation (RFA) to mitral leaflets and chordae can effect these repair goals to decrease MR. Methods: A total of seven canines were studied to assess the effects of RFA on mitral valve structure and function. RFA was applied ex vivo (n = 1), acutely in vivo using a right lateral thoracotomy and cardiopulmonary bypass (n = 3), and chronically in vivo using percutaneous access to the heart (n = 3). RFA was applied to the mitral valve and its associated chordae. Mitral valve structure and function (in vivo preparations) were then assessed. Results: Ex vivo application of RFA resulted in qualitative reduction in mitral leaflet surface area and chordal length. Acute in vivo application of RFA to canines found to have MVP causing severe MR demonstrated a 43.7–60.7% statistically significant (P = 0.039) reduction in postablation MR. Chronic, in vivo, percutaneous application of RFA was found to be feasible and the engendered alterations durable. Conclusion: These data suggest that myxomatous mitral valve repair using radiofrequency energy delivered via catheter is feasible.     

Two-dimensional echocardiographic mitral valve prolapse: evidence for a relationship of echocardiographic morphology to clinical findings and to mitral annular size

Fifty adult patients with two-dimensional echocardiograms (2DE) meeting standard diagnostic criteria for mitral valve prolapse (MVP) were studied to evaluate the significance of a positive 2DE by using a new morphologic grading system, a simplified method for annular measurement, and clinical data. Patients with mild (grade I) 2DE MVP differed significantly from those with moderate (grade II) to severe (grade III) 2DE MVP. Mild prolapse patients were predominantly female (p = 0.05) and younger (p less than 0.01). Atypical physical findings were associated with mild MVP while mitral insufficiency murmurs were associated with moderate to severe MVP (p less than 0.0025). When present, atypical chest pain and/or low-grade ventricular ectopy were associated with mild 2DE MVP, while pulmonary congestion, high-grade ectopy, and/or endocarditis were associated with moderate to severe 2DE MVP (p less than 0.001). Symptomatic moderate to severe 2DE MVP patients tended to have large annular dimensions. Additional echocardiographic characteristics of mild 2DE MVP included insensitivity of the parasternal long-axis 2DE view in its detection (p = 0.00002), predominance of anterior leaflet involvement in the apical 2DE view (p = 0.01), and absence of significant difference from age- and sex-matched control subjects in any annular dimension. In contrast, moderate to severe 2DE MVP showed highly significant differences from age- and sex-matched control subjects and from each other in all annular dimensions. Echocardiographically mild MVP defines a subgroup which differs quantitatively and clinically from more advanced morphologic variants. The use of mild 2DE MVP as a diagnostic criterion for MVP should be qualified as being "of questionable diagnostic significance." When present, with or without corroborative auscultatory findings, it may define a subgroup of prolapse at lower risk of significant clinical events or one that represents a normal echocardiographic variant. New grading and annular measurement methodologies provide additional tools for 2DE analysis of MVP with potentially important clinical and prognostic implications.     

Doppler echocardiographic analysis of the short-term results of surgical repair of mitral valve prolapse in myxomatous degeneration

Ten consecutive patients with pure mitral regurgitation due to floppy valve underwent valve repair operations. Postoperative mitral continence or regurgitation and diastolic flow across the valve were evaluated by Doppler echocardiography. Mean follow-up was 6.4 months. Four patients showed minimal and 3 mild regurgitation; no regurgitation was detected in 3. A significant peak diastolic atrioventricular gradient (10 mmHg) was observed in only one patient. All patients showed symptomatic improvement and a decrease in ventricular diameters. Repair of floppy mitral valves is feasible and gives good results. Doppler echocardiography is a useful technique for monitoring postoperative valve function.     

M mode and cross-sectional echocardiographic features of flail posterior mitral leaflets

Seventeen patients with accepted M mode echocardiographic criteria for flail mitral leaflet were studied. M mode echocardiograms revealed characteristic disordered mitral valve motion: (1) 16 (94 percent) had chaotic diastolic mitral motion; (2) 14 (82 percent) had systolic mitral flutter; (3) 14 (82 percent) had systolic left atrial echoes; and (4) 12 (71 percent) had systolic mitral valve prolapse. In 8 patients (47 percent) all four findings were present, with three findings present in 16 (35 percent) and two findings present in 13 (18 percent); none had fewer than two findings. Cross-sectional echocardiographic studies in 10 patients revealed a systolic whipping motion of the posterior mitral leaflet into the left atrium in all, abnormal systolic mitral coaptation in all and an abnormal mass of systolic left atrial echoes in 4. None of the first three M mode criteria were observed in 230 patients with uncomplicated “mid systolic click-late systolic murmur” syndrome; cross-sectional echocardiography in 30 of 230 patients revealed normal systolic mitral coaptation and no systolic whipping of the tip of the posterior mitral leaflet into the left atrium.     

Reconsideration of echocardiographic standards for mitral valve prolapse: lack of association between leaflet displacement isolated to the apical four chamber view and independent echocardiographic evidence of abnormality

Mitral valve prolapse by current echocardiographic criteria can be diagnosed with surprising frequency in the general population, even when preselected normal subjects are examined. In most of these individuals, however, prolapse is present in the apical four chamber view and absent in roughly perpendicular long-axis views. Previous studies have shown that systolic annular nonplanarity can cause apparent prolapse in the four chamber view without actual leaflet displacement above the most superior points of the anulus, and there is evidence for such nonplanarity in vivo. It is then reasonable to ask whether superior leaflet displacement limited to the four chamber view has any pathologic significance or complications. The purpose of this study, therefore, was to address the following hypothesis: that patients with superior leaflet displacement confined to the four chamber view have no higher frequency of associated echocardiographic abnormalities than do patients without displacement in any view. Such abnormalities, which would provide independent evidence of mitral valve pathology or dysfunction, include leaflet thickening, left atrial enlargement and mitral regurgitation. Leaflet displacement was measured in the parasternal long-axis and apical four chamber views in 312 patients who were studied retrospectively and selected for the absence of forms of heart disease other than mitral valve prolapse. Leaflet thickness and left atrial size were measured and mitral regurgitation was graded. Patients with leaflet displacement limited to the four chamber view were no more likely to have associated abnormalities than were patients without displacement in any view (0 to 2% prevalence, p greater than 0.5). In contrast, patients with leaflet displacement in the long-axis view were significantly more likely to have associated abnormalities (12 to 24%, p less than 0.005), the frequency of which increased with the extent of leaflet displacement in that view (p less than 0.0001). These results suggest that displacement limited to the apical four chamber view is, in general, a normal geometric finding unassociated with echocardiographic evidence of pathologic significance.     

Non-myxomatous flail mitral valve: clinical and echocardiographic characteristics and long-term clinical outcome

BACKGROUND AND AIM OF THE STUDY: Chordal rupture leading to flail mitral valve and mitral regurgitation (MR) is considered to be caused primarily by myxomatous mitral valve disease. The study aim was to determine the prevalence and clinical and echocardiographic characteristics of non-myxomatous versus myxomatous flail mitral valve. METHODS: A total of 96 patients with flail mitral valve was identified from an echocardiography database and classified as either myxomatous (n = 36; 37%) or non-myxomatous (n = 60; 63%), based on echocardiographic mitral valve anatomy (systolic leaflet buckling). In 10 other patients the etiology was indeterminate. The clinical and echocardiographic characteristics and outcome at five years were compared between groups. RESULTS: Patients with non-myxomatous mitral valve were older than those with myxomatous mitral valve (mean age 76 +/- 9 versus 61 +/- 12 years; p <0.0001), and were more likely to have aortic sclerosis, mitral annulus and papillary muscle calcification (odds ratio 3.6, 95% CI 1.2-10.8, p = 0.02) and to have short duration of symptoms (< or =1 month, p <0.02). There was no inter-group difference in MR severity, but non-myxomatous patients had higher systolic pulmonary artery pressure (52 +/- 16 versus 42 +/- 13 mmHg, p = 0.008). During the five-year follow up period, non-myxomatous patients had a poorer crude survival and survival free from rehospitalization for heart failure (p = 0.02), and were less likely to have mitral valve surgery (p = 0.015). However, these differences were abolished when data were adjusted for age. CONCLUSION: Among patients with flail mitral valve referred for echocardiography, more than half were non-myxomatous in origin, most likely due to wear and tear. Non-myxomatous flail mitral valve was associated with older age, degenerative calcific valvular changes, and more recent onset of symptoms. Age-adjusted survival free of heart failure was similar in both non-myxomatous and myxomatous patients.     

Non-resectional repair of myxomatous mitral valve disease: the 'American Correction'

The 'American Correction', as proposed by Lawrie for myxomatous mitral valve disease, utilizes artificial chords and a flexible annuloplasty ring sutured in place with a running technique. Leaflet resection is not performed. The aim of this review is to describe the physiologic basis of this repair, to contrast it with the Carpentier approach, and present the surgical technique in detail.     

Statistical comparison of M mode and two dimensional echocardiographic diagnosis of flail mitral leaflets

Forty-five patients who had surgical therapy for pure mitral insufficiency were evaluated prospectively with both M mode and two dimensional echocardiography; 26 patients (Group I) had a flail mitral valve leaflet, and 19 patients (Group II) had intact chordae tendineae. The M mode echocardiographic criteria of a flail valve (systolic left atrial echoes, systolic mitral valve flutter, diastolic mitral flutter and chaotic paradoxic diastolic posterior leaflet motion) were compared statistically with the two dimensional echocardiographic criterion (loss of systolic leaflet coaptation). The presence of one M mode echocardiographic finding had a sensitivity of 60 percent, a specificity of 53 percent, a predictive accuracy of 63 percent and a predictive value of 50 percent. The sensitivity (96 percent), specificity (84 percent), predictive accuracy (89 percent) and predictive value (94 percent) of the two dimensional echocardiogram were statistically superior to those of the M mode study (p < 0.05 or better for each criterion). Thus, two dimensional echocardiography is distinctly superior to M mode echocardiography in the diagnosis of flail mitral valve leaflets.