Standardized approach to extract candidate outcomes from literature for a standard outcome set: a case- and simulation study.

AIMS: Standard outcome sets enable the value-based evaluation of health care delivery. Whereas the attainment of expert opinion has been structured using methods such as the modified-Delphi process, standardized guidelines for extraction of candidate outcomes from literature are lacking. As such, we aimed to describe an approach to obtain a comprehensive list of candidate outcomes for potential inclusion in standard outcome sets. METHODS: This study describes an iterative saturation approach, using randomly selected batches from a systematic literature search to develop a long list of candidate outcomes to evaluate healthcare. This approach can be preceded with an optional benchmark review of relevant registries and Clinical Practice Guidelines and data visualization techniques (e.g. as a WordCloud) to potentially decrease the number of iterations. The development of the International Consortium of Health Outcome Measures Heart valve disease set is used to illustrate the approach. Batch cutoff choices of the iterative saturation approach were validated using data of 1000 simulated cases. RESULTS: Simulation showed that on average 98% (range 92-100%) saturation is reached using a 100-article batch initially, with 25 articles in the subsequent batches. On average 4.7 repeating rounds (range 1-9) of 25 new articles were necessary to achieve saturation if no outcomes are first identified from a benchmark review or a data visualization. CONCLUSION: In this paper a standardized approach is proposed to identify relevant candidate outcomes for a standard outcome set. This approach creates a balance between comprehensiveness and feasibility in conducting literature reviews for the identification of candidate outcomes.

[Annuloplasty reduces the mitral leaflets mobility]. / L'annuloplastie réduit la mobilité des deux feuillets mitraux.

The posterior mitral leaflet is usually motionless following mitral valve repair. The aim of this study was to assess (1) the geometric changes of the left ventricular base following prosthetic ring annuloplasty and (2) their impact on the anterior mitral leaflet (AML) mobility. Thirty five patients operated upon for mitral valve repair underwent an intraoperative transesophageal echographic study before and after annuloplasty. A posterior leaflet resection was achieved in 29 cases and ring annuloplasty alone in 6 cases. No repair technique was performed on the AML. Four parameters were assessed: the anteroposterior mitral annulus diameter, the aortomitral angle, the opening and closure angles of the AML. Annuloplasty resulted in a drastic reduction of the mitral annulus from 36.8 +/- 5.6 mm to 20.9 +/- 3.8 mm (systole, long axis view) (p < 0.0001). The aortomitral angle decreased following annuloplasty from 115.1 +/- 8.3 to 108.0 +/- 9.60 (systole, long axis view) (p < 0.0001). No difference was observed between systolic and diastolic measurments concerning the mitral annulus or the aortomitral angle. The opening angle of the AML remained unchanged whereas the closure angle increased from 17.8 +/- 6.10 to 26.6 +/- 6.70 (long axis view) (p = 0.0001) resulting in a displacement of the coaptation point towards the apex. Consequently, the excursion of the anterior leaflet throughout the cardiac cycle decreased following annuloplasty from 43 +/- 130 to 32.5 +/- 11 (long axis view) (p < 0.0001).

Hemodynamic evaluation of a new stentless autologous pericardial mitral valve.

BACKGROUND: There is no satisfactory mitral valve prosthesis. An ideal mitral valve substitute should be biologic, nonantigenic, and anatomically correct. METHODS: We developed a stentless, chordal-supported (including anterior basal stay chords) mitral valve made with glutaraldehyde-treated autologous pericardium. Eight such prostheses were implanted in sheep. RESULTS: Seven animals survived the operation and were studied postoperatively immediately, at 1 week, and at 1 month. Simultaneous left ventricular and left atrial pressures showed peak and mean transvalvular pressure gradients of 6+/-2 mm Hg and 1+/-1 mm Hg, respectively. Echocardiography performed intraoperatively and then 1 week and 1 month postoperatively showed normal valve leaflet movements. Color and pulsed Doppler echocardiography showed no sign of transvalvular stenosis or regurgitation. Effective orifice area was 5.39+/-0.35 cm2 at intraoperative, 5.51+/-0.29 cm2 1 week after operation (n = 5), and 5.51+/-.28 cm2 1 month after operation (n = 3). Three animals were sacrificed at 19 days and at 1 and 3 months. One animal is alive at 10 months. CONCLUSIONS: This new stentless pericardial mitral valve performed satisfactorily with low gradients and no regurgitation. Possible advantages of this pericardial valve are excellent hemodynamics, ease of construction and implantation, lack of immunogenicity, and low cost. Similarly designed valves but with a shorter nonglutaraldehyde treatment time have been used in 3 sheep monitored for more than 3 months.

Mitral homograft for tricuspid valve endocarditis complicating a congenital fistula between the right coronary artery and right ventricle.

The authors report a case of tricuspid endocarditis complicating a congenital coronary artery fistula to the right ventricle in an eight-year-old female. The patient underwent valve replacement using a cryopreserved mitral homograft. Six months later, clinical and echocardiographic status are excellent. Using a mitral homograft for tricuspid endocarditis is a recognized approach in adults, whereas in pediatric cases it is exceptional. Homografts could prove to be a valid procedure in children when repair is not feasible, although one could expect a more rapid deterioration.

A four-dimensional study of the aortic root dynamics.

OBJECTIVE: Although aortic root expansion has been well studied, its deformation and physiologic relevance remain controversial. Three-dimensional (3-D) sonomicrometry (200Hz) has made time-related 4-D study possible. METHODS: Fifteen sonomicrometric crystals were implanted into the aortic root of eight sheep at each base (three), commissures (three), sinuses of Valsalva (three), sinotubular junction (three), and ascending aorta (three). In this acute, open-chest model, the aortic root geometric deformations were time related to left ventricular and aortic pressures. RESULTS: During the cardiac cycle, aortic root volume increased by mean+/-1 standard error of the mean (SEM) 33.7+/-2.7%, with 36.7+/-3.3% occurring prior to ejection. Expansion started during isovolumic contraction at the base and commissures followed (after a delay) by the sinotubular junction. At the same time, ascending aorta area decreased (-2.6+/-0.4%). During the first third of ejection, the aortic root reached maximal expansion followed by a slow, then late rapid decrease in volume until mid-diastole. During end-diastole, the aortic root volume re-expanded by 11.3+/-2.4%, but with different dynamics at each area level. Although the base and commissural areas re-expanded, the sinotubular junction and ascending aorta areas kept decreasing. At end-diastole, the aortic root had a truncated cone shape (base area>commissures area by 51.6+/-2.0%). During systole, the root became more cylindrical (base area>commissures area by 39.2+/-2.5%) because most of the significant changes occurred at commissural level (63.7+/-3.6%). CONCLUSION: Aortic root expansion follows a precise chronology during systole and becomes more cylindrical - probably to maximize ejection. These findings might stimulate a more physiologic approach to aortic valve and aortic root surgical procedures.

Aortic and pulmonary root: are their dynamics similar?

OBJECTIVES: The long-term behavior of the pulmonary autograft in the aortic position (Ross procedure) remains uncertain. Using three-dimensional (3D) sonomicrometry (200 Hz) we compared the dynamics of the aortic and pulmonary roots. METHODS: Twenty-four crystals were implanted in each aortic (eight sheep) and pulmonary roots (six sheep) at: base (3 x 2), commissures (3 x 2), sinotubular junction (3 x 2), ascending aorta (3) and pulmonary trunk (3). Under stable hemodynamic conditions, geometric changes were time-related to left ventricular pressure (LV) and aortic pressure. RESULTS: The expansion of the aortic root is twice that of the pulmonary root. During the cardiac cycle, the aortic root volume increased by 37.7 +/- 2.7% (mean +/- SEM) versus 20.9 +/- 1.0% for the pulmonary root. Both were cone-shaped at end diastole. Because expansion at commissures was twice that of the base, both roots became more cylindrical during ejection. Although both roots started to expand prior to ejection and reached maximal expansion during the first third of ejection, the commissural and sinotubular junction dynamics were different in each root. While in the aortic root, expansion at commissural and sinotubular junction levels was significantly different (63.7 +/- 3.6% versus 37.0 +/- 2.1%), in the pulmonary root, they were similar (29.0 +/- 1.3% versus 27.7 +/- 1.4%). Expansion of the three sinuses was also different (P<0.001). In the aortic root: the right expanded more than the left and more than the non-coronary sinus. In the pulmonary root: the right sinus expanded more than the anterior more than the left. CONCLUSIONS: Dynamic differences might explain the global pulmonary root dilatation when subjected to systemic pressure, particularly at the level of the sinotubular junction which might result in the autograft failure. Differences in the asymmetrical expansion of the aortic and pulmonary roots should be considered for the implantation of the pulmonary autograft in the most physiological position.

[Widening plasty of the anterior cusp in rheumatic mitral insufficiency]. / Plastie d'élargissement de la valve antérieure dans l'insuffisance mitrale rhumatismale.

UNLABELLED: The mechanism of insufficiency in rheumatic valve disease includes 1. annulus dilatation and 2. restricted leaflet motion. Aiming at improving the treatment of restriction, augmentation of the anterior mitral leaflet (AML) was achieved with a piece of autologous pericardium. METHODS: between January 1995 and December 1999, out of 274 patients refered for rheumatic mitral disease, 143 patients underwent a repair (52%), 81% of them had pure regurgitation with no stenosis. Ring annuloplasty was performed in all cases. Two techniques used for treating the restrictive componant of the regurgitation were compared in two consecutive cohort of patients: no AML augmentation (n=62) and AML augmentation (n=81). Mean age was 42 + 3 years and all preoperative variables were comparable except for the incidence of redo patients who all underwent AML extension. RESULTS: in hospital mortality was 0.7% (n=1 with AML extension) and there was one early reoperation for a pericardial patch dehiscence. After a mean follow-up of 3.2 years, there was one sudden death (no AML extension). The reoperation rate was lower with (2.5%) than without (12.9%) AML augmentation (p<0.05). Echographic study showed a lower incidence of recurrency of mitral insufficiency when AML augmentation had been performed (grade 2: 9% and grade 3: 3%) as compared to no AML augmentation (grade 2: 35% and grade 3: 14%) (p<0.05). The mitral orifice area was larger (AML augmentation: 2.2 + 0.3 cm2 vs no AML augmentation: 1.8 + 0.4 cm2). CONCLUSION: ring annuloplasty alone failed to correct rheumatic mitral insufficiency in all cases. AML augmentation improved the quality of the repair and decreased the risk of reoperation.

[Left ventricular reconstruction after excision of a large fibroma]. / Reconstruction ventriculaire gauche après exérèse d'un volumineux fibrome.

The authors report the case of a 15 year old boy with a large left ventricular fibroma discovered after a series of syncopal episodes due to obstruction to ejection. The first attempt to remove the fibroma in Columbia was only partially successful. In view of the risk of death associated with this type of tumour, it was decided to offer the patient complete excision after a full morphological and functional evaluation of myocardial function and the consequences of the tumour on mitral valve function and on the coronary circulation. The operation was performed under cardiopulmonary bypass and aortic clamping by conventional surgery, associated with reconstruction of the cardiac free wall with a large patch of autologous pericardium which was necessary to avoid cardiac transplantation, the ultimate sanction in this indication.

[Intramural hematoma of the esophagus: a rare diagnosis]. / Hématome intramural de l'oesophage. Un diagnostic peu connu.

We describe three cases of spontaneous intramural hematoma of the esophagus, a rare pathology. The combination of chest pain, dysphagia and hematemesis and often the existence of hemostasis disorders or fragility of the mucosa, or trauma of the esophagus, should evoke the diagnosis. Radiology (thoracic scan, barium swallowing) and esophagoscopy enable confirmation of the diagnosis, permitting conservative treatment and simple spontaneous course of this pathology.

The aortomitral angle is suspended by the anterior mitral basal "stay" chords.

OBJECTIVES: The function of the anterior mitral basal "stay" chords (SC) is not yet known. Collagen fiber orientation of the anterior mitral leaflet (AML) suggests that local stress is directed from papillary muscles (PM) over SC and AML to fibrous trigones (FT), maintaining the aortomitral angle (AMA). It has been shown that narrowing of AMA increases risk of systolic anterior movement (SAM). METHODS: Sonomicrometry crystals were implanted in six sheep at the left ventricular (LV) apex, PM tips (M1, M2), FT (T1, T2), posterior mitral annulus (PMA), and base of aortic right coronary sinus (RCS). The retracting force of ascending aorta was measured. RESULTS: Transection of SC resulted in an increase of distance M1-T1 and M2-T2. Consequently, the AMA narrowed at end systole by -3.26+/-0.85 degrees (p<0.05) and at end diastole by -4.16+/-1.28 degrees (p<0.05). A force of 1.8+/-0.2 N was needed to pull the recoiling ascending aorta back to its original position. CONCLUSIONS: The elastic recoil of ascending aorta is balanced by SC, which connect PM to FT and constitute the center of the LV base. Transection of SC narrows AMA and increases the risk of SAM.