Echo cardiographic Parameters of Left Ventricle May Limit the Use of Multi Track Balloon Mitral Valvuloplasty

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1 Med. J. Cairo Univ., Vol. 78, No. 2, June: , Echo cardiographic Parameers of Lef Venricle May Limi he Use of Muli Track Balloon Miral Valvuloplasy SAEED KHALED, M.D.*; AYMAN SADEK, M.D.*; AKRAM EL DESOKY, M.D.** and REDA MOFTAH, M.Sc.** The Deparmens of Cardiology, Faculy of Medicine, Ain Shams Uiniversiy* and Naional Hear Insiue**. Absrac For over a decade balloon miral valvuloplasy has been he reamen of choice for severe miral senosis and replaced surgical commissuroomy in many seleced cases. In spie of his, balloon miral valvuloplasy has many disadvanages. Such disadvanage migh may relaed o he effec of lef venricular geomery which was proven o be changed in paien wih rheumaic miral senosis. The Aim of his Sudy: Was o evaluae he effec of differen lef venricular geomerical parameers on early resuls of balloon miral valvuloplasy using Muli-Track balloon sysem in paiens wih rheumaic miral senosis. Subjecs and Mehods: The sudy included (50 subjecs): Group I: 10 normal subjecs as a conrol group and group II: 40 paiens wih sympomaic rheumaic miral senosis undergoing Balloon Miral Valvuloplasy using muli rack sysem. Several echocardiographic parameers were measured in order o sudy he lef venricular geomery. The baseline crieria for all paiens in he wo groups were comparable wih no significan saisical difference beween hem. Lef venricular geomery in paiens wih MS showed ha he long axis of he lef venricle was shorer han in normal subjecs (7.2±0.7cm VS 7.9±0.5cm wih p<0.001 Greaer shor axis/long axis diameer raio a every level wih he mos pronounced in he apical (D3 / L 0.49 ±0.09 VS 0.40±0.05 p< LV spherical index was markedly increased in group II (0.57±0.09 VS 0.40±0.05 p< Successful dilaaion was achieved in 75% of paien. The lef venricular long axis was found o be he only LV geomerical parameer which affeced he early resuls of BMV as he shorer LV long axis was associaed wih he more incidence of non-opimal resuls. By ROC analysis, we reached a cu-off poin regarding longiudinal axis of he LV=5.09 cm o ensure an opimum resul (100% PPV and 76% NPV) using he muli rack sysem. Conclusion: Balloon valvuloplasy using he muli rack sysem is an effecive reamen for rheumaic miral senosis however he alered LV geomery especially he longiudinal axis may affec he early oucomes. Key Words: Balloon miral valvuloplasy Echocardiographic parameers Muli-rack balloon sysem. Correspondence o: Dr. Saeed Khaled, The Deparmen of Cardiology, Faculy of Medicine, Ain Shams Uiniversiy. Inroducion RHEUMATIC Miral senosis (MS) is a coninuous, progressive, lifelong disease, usually consising of a slow, sable course in he early years and progressive acceleraion laer in life [1]. Isolaed MS affecion occurs in 40% of he cases. While 50% of he cases have combined miral senosis and regurgiaion [2]. Criical miral senosis occurs when he opening is reduced o 1 cm 2, a his sage, elevaed lef arial pressure (LAP) is required o mainain a normal cardiac oupu [3]. This increase in lef arial pressure will lead o pulmonary hyperension, ricuspid and pulmonary incompeence and evenual righ hear failure [4]. The lef venricular geomery was found o be changed in paien wih rheumaic miral senosis. The paiens wih miral senosis had shorer long axis diameer and greaer shor axis/long axis diameer raios a every level wih he mos pronounced change in he apical segmen of he caviy [5]. Treamen of miral senosis include percuaneous balloon miral valvuloplasy (PBMV) and surgical herapy. Balloon miral valvuloplasy is an effecive mehod for reaing rheumaic miral valve senosis, producing good shor- and longerm resuls ha are comparable o surgical valvoomy [6]. Inoue, e al. [7] were he firs o perform percuaneous miral commissuromy in The good resul obained by he echnique had led o is increasing worldwide use [8]. The Muli-Track sysem is a recen varian of he double balloon echnique and aims o make he procedure easier hrough he use of wo balloons and only single guide wire Alhough he Muli- 191

2 192 Echocardiographic Parameers of Lef Venricle Track sysem is a simple procedure wih less cosly caheers; however, hese caheers have differen sizes bu single lengh which may no favor differen lef venricular geomerical paerns [9]. Aim of he work: The aim of his work is o sudying he effec of lef venricular geomery on early oucome in paien wih miral senosis undergoing balloon miral valvuloplasy using Muli-Track balloon sysem. Paiens and Mehods Candidaes included in his prospecive randomized sudy were chosen from paiens who presened o he cardiology deparmen, Ain Shams Universiy Hospial and Naional Hear Insiue in he period from May 2006 o March 2007 wih sympomaic rheumaic miral senosis. Trans-horacic echo cardio graphic sudy: All paiens were sudied wih M. mode, wo dimensional and color Doppler echocardiography before he procedure and 1 day afer he procedure. Wih paricular emphasis on: Miral valve area was calculaed by direc measuremen in shor axis parasernal view (plannimery) and by coninuous Doppler using pressure half ime formula. Echo sudy of oher valvular lesions. The morphological feaures of he miral valve leafle and sub valvular apparaus were assessed according o he scoring sysem described by Willkins. Lef venricular geomery. D 3 Candidaes were divided ino 2 groups: Group I : Included 10 normal healhy individual as a conrol group. Group II: Included 40 paiens wih sympomaic miral senosis undergoing balloon miral valvulo plasy using muli rack sysem. D2 L D 1 Paien inclusion crieria: 1- Rheumaic M.S wih MVA <_ 1.5 cm MV score <10 according o Wilkins score. 3- Absence or mild degree of miral regurgiaion. 4- Absence or mild degree of oher valvular diseases. 5- Absence of lef arial hrombus by ransoesophageal echocardiography. Paien exclusion crieria: 1-Associaed miral regurgiaion more han grade II. 2- Associaed aoric valve disease ha need surgical correcion. 3- Acue rheumaic aciviy or infecive endocardiis. 4- Hisory of recen hrombo-embolic even <2 monhs. 5- Lef arial hrombus on T.E.E performed wihin 24 hours before he procedure. Pre-Procedural assessmen: All paiens were subjeced o he following: Hisory aking and clinical examinaion, ECG, Laboraory invesigaions, Echocardiographic sudies: Apical view 4-chamber Parasernal long axis view Fig. (1): Schemaic diagram of cross-secional echocardiographic parasernal long axis (L) is represened by a line drawn from he endoccardium of he apex of he lef venrlcle o he midppin of an imaginary lion joining he anerior and poserior aach-mens of he miral leafles. Descripion of lef venricular geomery: The minor axis diameer (D-1) in he parasernal long axis view was measured a he level of he ips of he leafles of he miral valve. Minor axis diameers (D-2, D-3) in he apical four-chamber view are drawn perpendicular o he long axis, dividing he lef venricular caviy ino hree equal segmens. Lef venricular long axis diameer was measured a end of lef venricular diasole from mid miral annuls o lef venricular apex. Shor axis diameers were aken a 3 levels a end of lef venricular diasole: º D1 (basal line) was aken in long axis para sernal view. º D2 (mid caviy line) was aken in apical four chambers view.

3 Saeed Khaled, e al. 193 º D3 (apical line) was aken in apical four chambers view [10]. Measuremen of lef venricular geomery included he following parameers: 1- Shor axis/long axis raio were calculaed [10]. 2- Lef venricular spherical index was calculaed from EDV/[(LAD 3 xπ)/6] [11]. 3- Lef venricular relaive wall hickness (LV hyperrophy index from M. mode echo sudy h/r = [(PDTd + IVSTd)/2]/(EDD/2) wih normal rangc; [12]. 4- Lef venricular mass index: [13] Measuremen of LVMI by M. mode echocardiography. LVMI = (1.05 x [(EDD + PWTd + IVSTd) 3 EDD 3 ] 13.6)/BSA (g/m 2 ). Normal LVM index: Males: 76± 13 gm/m 2. Females: 66± 11 gm/m 2. EDV: End-diasolic volume, ml. LAD: Long axis, cm. BSA: Body surface area (m 2 ). EDD: LV end-diasolic diameer (cm). ESD: LV end-sysolic diameer (cm). IVSTd: Inervenricular diasolic hickness (cm). PWTd: LV posero-laeral diasolic wall hickness (cm). PWTs: LV posero-laeral sysolic wall hickness (cm). SAP: Sysolic arerial pressure (mmhg). Percuaneous balloon miral valvuloplasy procedures: BMV was performed wih Muli Track balloon, he size of balloons used was lef o he choice and he experience of he operaors aking in consideraion miral valve annulus measured by rans-esophageal echo. Hemodynamic assessmen was done immediaely before and afer he procedure, lef and righ hear caheerizaion wih deerminaion of inra cardiac and inra vascular pressures were performed. The ransmiral pressures gradien were measured. Pos procedural assessmen: Immediaely afer percuaneous balloon valvoomy paiens were subdivided as follows: Opimum resuls: Procedural success was defined as MVA > 1.5 cm 2 or increase by 40% from original area wih absence of major complicaions (cardiac amponade, cerebral embolism, severe miral regurgiaion needing urgen surgery and deah) wih miral regurgiaion less han grade II). Non-Opimum resuls: This included submaximal valve dilaaion, incomplee procedure or presence of major complicaions (severe MR needing surgery, lef venricular perforaion, embolic evens and deah). A deailed echocardiographic and Doppler assessmen following valvuloplasy was done measuring: rans-miral pressure gradien, MVA, MR, and pulmonary arery pressure. Saisical analysis: Daa were abulaed and saisically analyzed o evaluae he difference beween he groups under sudy as regards he various parameers. Resuls are expressed as mean ± SD. The saisical significance of differences beween groups was assessed by an analysis of variance (ANOVA) and. The correlaions were evaluaed by Pearson's es. Resuls are significan if p<0.05, highly significan if p<0.01, non significan if p>0.05. Resuls Demographic daa: As shown in Table (1), here was no significan saisical difference beween boh sudied groups; as regards he age, gender, weigh, heigh, hear rae, sysolic and diasolic blood pressure. As shown in Table (2) here is no significan saisical difference beween boh sudied groups as regards M-Mode echocardiographic daa including (LVEDD, LVESD, PWT, IVS, FS and EF%). As shown in Table (3): Lef venricular long axis is shorer in paiens wih rheumaic MS han in normal subjecs (6.46 ± 0.82 cm Vs 7.75±0.48cm) wih significan saisical differen (p<0.000). Minor shor axis (widh axis) of lef venricle in paiens wih rheumaic MS were shorer in every segmen han normal persons. Basal shor axis (D1) (4.16 ±0.47 Vs 4.74±0.39 cm, p<0.001). Mid shor axis (D2) (3.53 ±0.39 cm Vs 4.16±0.22 cm, p<0.000). Apical segmen (D3) (3.09 ±0.41 cm Vs 2.68±0.21 cm, p<0.004).

4 194 Echocardiographic Parameers of Lef Venricle There was significan saisical difference beween paien group and normal persons in every level of minor shor axis. Table (1): Baseline demographic daa of boh conrol group and paien group. Age (yrs): Heigh (cm): Weigh (kg): HR (Bea/min): BPs (mmhg): BPd (mmhg): Sex: Male Female Demographic daa Group I ± ± ± ± ± ±8.23 Group II ± ± ± ± ± ± Group I Group II No. % No. % Table (2): M-mode echocardiographic parameers in boh sudied groups. LVEDD: Trans horacic ECHO cardio graphic daa Group I n = ±0.45 Group II n = ± Table (3): Dimensional descripors of lef venricular geomery in boh paien and conrol groups. L: D1: D2: D3: Lef venricular geomery Conrol ± ± ± ±0.21 Paiens ± ± ± ± As shown in Table (4), he breadh o lengh (D/L) raio in every segmen of he lef venricle has no significan saisical difference excep in apical segmen only (p<0.000). Table (4): Measuremen of lef venricular geomery in boh paiens and normal conrol group. D1/L: D2/L: D3/L: Lef venricular geomery Conrol ± ± ±0.03 Paiens ± ± ± As shown in Table (5), here was highly significan saisical difference beween he paien group and normal group regarding spherical index (0.56±0.07 Vs 0.40±0.03, p<0.001). LVESD: PWT: ± ± Table (5): Mean and sandard deviaion of lef venricular spherical index in boh sudied groups. Lef venricular geomery (spherical index) IVS: FS: EF%: ± ± ± ± ± ± ± ± LVsph: Conrol ±0.03 Paiens ± As shown in Table (6), here was no significan saisical difference beween boh sudied groups as regarding o LV MI and LV relaive wall hickness.

5 Saeed Khaled, e al. 195 Pre dilaaion assessmen: As shown in Table (8), he immediae resuls of BMV in group II: opimum resuls were reached in 30 cases, non-opimum resuls were seen in 10 paiens as follows: four cases developed inraprocedural amponade wih no need for surgical inerference excep in one case ha necessiaed operaive ransfer and died in operaing heare, 4 cases developed severe miral regurgiaion which planned for elecive miral valve replacemen, 2 cases he MVA failed o reach he desirable area. Mean and sandard deviaion of comparaive resuls of boh pre- and pos-dilaaion in paiens underwen BMV using Muli-Track balloon sysem (Group II) showed ha Miral valve area (MVA) increased from (1.05 ±0.147 cm 2 ) o reach (1.789 ± cm 2 ), (p<0.001) wih significan saisical difference. Mean Miral pressure, across he miral valve decrease from (12.05 ±3.5) before dilaaion o (4.447±2.315 mmhg) afer dilaaion wih sig- nifican saisical difference (p<0.001), Mean pulmonary arery sysolic pressure drop from (41.5 ± mmhg) o ( ± mmhg) pos dilaaion wih significan saisical difference (p<0.001). Gradien across miral valve by lef hear caheerizaion drop from (15.1 ±3.64 mmhg) o (3.526±2.19 mmhg) wih significan saisical difference (p<0.001). Table (6): Mean and sandard deviaion of lef venricular mass index and lef venricular relaive wall hickness in boh sudied groups. LVmass index: LVrw: Lef venricular geomery Conrol ± ±0.02 Paiens ± ± Table (7): Baseline hemodynamic characerisics of all paiens in group II. Pre-dilaaion daa MVA (cm 2 ) Mean miral pressure (mmhg) Mean PASP (mmhg) Mean gradien across miral valve by caheerizaion (mmhg) Mean lef arial pressure (mmhg) Group II 1.050± ± ± ± ±7 Table (8): Immediae resuls of BMV. Oucome Techni. No. of paiens Opimum Non-Op. Non-Opimum Subopimal Cardiac Severe Deah valve dilaaion amponade miral R Embolic Muli-rack (75%) Relaion of lef venricular geomery and immediae resuls of BMV: As shown in Table (9) here was no saisical significance beween opimum and non opimum group regarding D1, D2, and D3; however Lef venricular long axis (L) was (6.63 ±0.74cm) Vs (5.95±0.86cm) in non-opimum resuls (p=0.021). Table (9): Mean and sandard deviaion of relaion of dimensional descripors of lef venricular geomery and immediae resuls of BMV using muli-rack sysem. Non opimum Opimum L 5.95± ± * D1 4.00± ± D2 3.38± ± D3 2.87± ± Relaion of measuremens of lef venricular geomery and immediae resuls: As shown in Table (10), here were no significan saisical difference beween opimum and non opimum group regarding breadh o lengh raio a every level and lef venricular spherical index. he same was observed also in he lef venricular mass index and lef venricular relaive wall hickness 0.38±0.03 versus 0.38±0.03 (p=0.896). Table (10): Mean and sandard deviaion of measuremen of lef venricular geomery and immediae resuls afer BMV using muli-rack sysem. Non opimum Opimum D1/L 0.67± ± D2/L 0.57± ± D3/L 0.49± ± LVsph index 0.55± ±

6 196 Echocardiographic Parameers of Lef Venricle Correlaion beween pos-dilaaion miral valve area and lef venricular long axis (L): As shown in Table (11), here was a posiive correlaion beween lef venricular long axis and pos-valvuloplasy miral valve area (p=0.038). Table (11): Correlaion beween lef venricular long axis and pos-bmv miral valve area. Miral Valve Area Lef (L) venricular long axis: r * Correlaions beween lef venricular long axis and immediae pos-dilaaion gradien by lef hear caheerizaion: As shown in Table (12), here was a negaive correlaion beween lef venricular long axis and immediae pos-dilaaion gradien across miral valve by lef hear caheerizaion, wih significan saisical value (p<0.001). Table (12): Correlaion beween lef venricular long axis and pos-dilaaion gradien. Pos-Dilaaion gradien by lef hear caheerizaion Lef (L) venricular long axis: r ROC in Muli-Track group: As shown in Table (13), he cu off poin of LV logudinal long axis for Muli-Track sysem was 5.09 cm wih specificiy 100% and sensiiviy 42.9%. Table (13): Cu off poin in Muli-Track group. ROC of L in (group IIa) Cuoff Sens. Spec. +PV -PV Accuracy <= Discussion Rheumaic fever and rheumaic hear disease sill form a major healh problem in developing counries including Egyp. Rheumaic fever is considered as he predominan cause of miral senosis [14]. Rheumaic inflammaion of he lef venricular myocardium is common in paiens wih miral senosis [15]. This process ofen leads o anaomical disorion of he lef venricle and miral apparaus [16]. However, his process is usually relaed o subvalvular fibrosis along wih he involvemen of poserobasal segmen. The saus of inrinsic conraciliy is conroversial, and so abnormal inrinsic conraciliy in miral senosis should lead o archiecural remodeling even in absence of segmenal asynchrony [5]. Collagen marix is responsible for mainaining he alignmen of cardiac muscle fibres.this provides ensile srengh o he muscle o resis deformaion. Ulrasrucural changes of a myopahic process involving he collagen marix have been shown in he lef venricular myocardium of he paiens wih miral senosis [15]. An increase in chamber size wihou aleraion in shape is possibly an adapive response o variaions in work load. A change in venricular shape wihou an increase in venricular size as shown in he paiens wih miral senosis is morphological evidence of a myopahic process. Alered lef venricular geomery may be relaed o he severiy of he pahological changes and hence may precede or follow he onse of lef venricular sysolic dysfuncion depending on he role played by he loading facors. So, he lef venricular shape in paiens wih rheumaic miral senosis is less ellipsoidal due o archiecural remodeling along wih increased wall sress. In he normal ellipsoidal venricle, he posiion of he papillary muscle permis heir conracions o exer a verical force on he chordae de endinae [10]. This significanly conribues o he lef venricular long axis dynamics owards ejecion performance and mainenance of he miral valve orifice compeence. In a more spherically shaped venricle, he papillary muscles undergo laeral migraion and hence may be responsible for he occurrence of miral regurgiaion following miral commissuroomy besides he adverse effecs on he long axis dynamics [5]. The inroducion of percuaneous rans-sepal miral commissuroomy, modified once again he herapeuic sraegy for miral senosis, and decreased he need for surgery. The early and lae resuls of balloon valvuloplasy were comparable o surgical echniques bu wihou he risks and complicaions of general aneshesia and exracorporeal circulaion pump [17]. The double balloon sysem was inroduced for he firs ime in 1986 [18]. The Muli-Track sysem is a recen varian of he double balloon echniques and was inroduced by Bonhoeffer [17], as a valid alernaive o he exising procedure for reamen of miral senosis

7 Saeed Khaled, e al. 197 ha simplifies he procedure and reduce he cos of miral dilaaion. Lef venricular geomery: In he presen sudy: Our observaions suggesed ha he lef venricular caviy shape in paiens wih rheumaic MS ends o approach a spherical shape or less ellipsoidal and his process is mos marked in he apical segmens so he venricular apical area ends o be hinner han he res of he lef venricular myocardial wall. This was seen in our measuremen of LV geomery as: Long axis was shorer in paiens wih MS han normal subjecs. Minor shor axis were shorer in paiens wih MS han normal subjecs a 3 levels (D1, D2, and D3). The shor axis/long axis diameer raio was more and saisically significan a he level of he apical segmen. The lef venricular end diasolic spherical index increased in paiens wih rheumaic MS. Lef venricular mass index and relaive wall hickness (hyperrophy index) were no significanly alered neiher in group 1 nor group 2. Yoshida, e al. [19] sudied he cross secional lef venricular geomery of abnormal lef venricular configuraion and conracion in paiens wih rheumaic MS. The sudy included 40 paiens, abnormal configuraion and asynergy were observed in 23 paiens (56%), he lef venricular shape divered from circular o half moon or pear like configuraion. The same resuls were obained by Mohan, e al. [5] when hey sudied cross secional echocardiography in 20 paiens wih rheumaic MS and 20 normal subjecs, hey found ha he Long axis of he lef venricle was shorer in paiens wih rheumaic MS han in normal subjecs (7.2 ±0.7 cm VS 7.9±0.5 cm wih p< Greaer shor axis/long axis diameer raio a every level wih he mos pronounced in he apical (D3/L 0.49 ±0.09 VS 0.40±0.05 p<0.001). LV spherical index was markedly increased (0.57 ±0.09 Vs 0.40±0.05 p< Such changes in he configuraion of he LV migh be aribued o he progression of he disease resuling from calcificaion, fibrosis and hinning of he myocardium [10]. Immediae resuls of BMV: Miral valve area (MVA): In he presen sudy, showed ha he MVA significanly increased from (1.047±0.15cm 2 ) o (1.789 ±0.373cm 2 ) wih high significan saisical difference beween pre- and pos-dilaaion MVA (p<0.001). El Sayed, e al. [20] published a comparaive sudy beween various mehods of percuaneous miral commissuroomy meallic valvoome, Inoue balloon and double balloon, each group comprised 50 paiens. Their resuls were improvemen in he MVA by similar degree in double balloon and meallic valvoome (2.1 ±0.5 cm 2, 2.0± 1.2cm 2 respecively) and greaer han Inoue group (1.87 ± 0.4cm 2 ), hey concluded ha in conras o Inoue balloon echnique, meallic valvoome and double balloon produced an excellen and comparable early improvemen of MVA associaed wih minimal complicaions. Cribier, e al. [21] (published he immediae resuls of balloon miral valvuloplasy by Inoue balloon and double balloon. The resuls obained ha MVA reach less han 2cm 2 in he majoriy of he cases, bu double balloon ranging (1.93 ± 0.34cm 2 ), while in Inoue balloon group (1.84 ± 0.412cm 2 ). Relaion of differen lef venricular geomerical parameers and Immediae resuls of BMV using Muli Track balloon sysem and double balloon sysem: Paul, e al. [22] described he crieria of successful BMV as increase of MVA more han 1.5cm 2 or 40% increase of MVA from pre-dilaaion area wih absence of major complicaion (lef venricular perforaion, cardiac amponade, severe miral regurgiaion and deah. In our presen sudy, we concluded ha he lef venricular long axis significanly affeced he early resuls of BMV in group II.LV long axis was shorer in non opimum group (5.95 ±0.86cm), while in opimum group i was (6.63 ±0.74cm) wih significan saisical difference p< On he oher hand, minor shor axis, lef venricular spherical index, lef venricular mass index and LV hyperrophy index had no relaion o he immediae resuls of BMV. In addiion by ROC analysis we reached a cu off poin for LV longiudinal axis=5,09 cm in Muli- Track group o achieve opimum resuls a value ha reached 100% posiive predicive value and 76.5% negaive predicive value. As far as we know, we did no reach similar researches in he lieraure sudying he effec of he LV geomery and is impac on he success of

8 198 Echocardiographic Parameers of Lef Venricle balloon miral valvuloplasy as o compare hem wih our resuls. Conclusion: The sudy concluded ha: Lef venricular geomery is changing in paiens wih rheumaic MS, hese changes appear mainly in: º Shor long axis lengh. º Shor minor shor axises. º Increased lef venricular spherical index. Percuaneous miral valvuloplasy using Muli- Track improved MVA and significanly reduced ransmiral pressure gradien, mean lef arial pressure. Only lef venricular long axis affeced he immediae resuls of BMV as he shorer long axis he more incidence of non opimum resuls. Limiaions: Small number of paiens included in he sudy. Oher variable migh migh have affeced he non opimum resuls as operaor 's experience. Oher ype of balloon valvuloplasy migh be have been used (e.g. Inoue) and compare is resuls o muli rack. Oher comparaive sudies are necessary. Recommendaions: Lef venricular long axis should be aken in consideraion when choosing he proper sysem used in dilaaion process especially when he lengh of he axis is less han 5.1. References 1- LESLIE D., HALL T.S., GOLDSTEIN S. and SHINDLER D.: Mural lef arial hrombus: A hidden danger accompanying cardiac surgery. J. Cardiovasc. Surg. (Torino). Oc., 39 (5): , EGUSHI K., OHKATI E. and MATSUMARA: Perioperaive arial fibrillaion as he key deerminan of oucome of miral v alve repair for degeneraive mal regurgiaion Eur. Hear J., 26: , MEISNER J.S., KEREN G., e al.: Arial conribuion o venricular filling in miral senosis, Circulaion, 84: , GAASCH W.H. and FOLLAND E.D.: Lef venricular funcion in rheumaic miral senosis. Eur. Hear J. Jul., 12 (Suppl B): 66-9, MOHAN J.C. and CALTON R.: Cross secional echocardiographic lef venricular geomery in rheumaic miral senosis, In. J. Cardio., 38 (1): 81-87, REYES V.P., RAJU B.S., WYNNE J., STEPHENSON L.W., RAJU R., FROMM B.S., RAJAGOPAL P., MEHTA P., SINGH S., RAO D.P., e al.: Percuaneous balloon valvuloplasy compared wih open surgical commissuroomy for miral senosis. N. Engl J. Med. Oc., 13, 331 (15): 961-7, FELDMAN T., HERRMANN H.C. and INOUE K.: Technique of percuaneous ransvenous miral commissuroomy using he Inoue balloon caheer. Cahe. Cardiovasc. Diagn., Suppl, 2: 26-34, HUNG J.S., FU M., YEH K.H., CHUA S., WU J.J. and CHEN Y.C.: Usefulness of inracardiac echocardiography in ranssepal puncure during percuaneous ransvenous miral commissuroomy. Am. J. Cardiol. Oc., 1, 72 (11): 853-4, VAHANIAN A. and PALACIOS I.F.: Percuaneous approaches o valvular disease. Circulaion. Apr., 6, 109 (13): , KONO T., SABBAH H.N., STEIN P.D., BRYMER J.F. and KHAJA F.: Lef venricular shape as a deerminan of funcional miral regurgiaion in paiens wih severe hear failure secondary o eiher coronary arery disease or idiopahic dilaed cardiomyopahy. Am. J. Cardiol. Aug., 1, 68 (4): 355-9, LAMAS G.A., VAUGHAN D.E., PARISI A.E. and PFEF- FER M.A.: Effecs of lef venricular shape and capopril herapy on exercise capaciy afer anerior wall acue myocardial infarcion. Am. J. Cardiol., 63: 1167, REICHEK N., WISON J., ST JOHN SUTTON M., PLAP- PERT T.A., GOLDBERG S. and HIRSHFELD J.W.: Noninvasive deerminaion of lef venricular end-sysolic sress: Validaion of he mehod and iniial applicaion. Circulaion, 65: 99, DEVEREUX R.B. and REICHEK N.: Echocardiographic deerminaion of lef venricular mass in man: Anaomic validaion of he mehod. Circulaion, 55: 613, OLSON L.J.: Surgical pahology of he miralvalve: Asudy of 712 cases spanning 21 years. Mayo. Clini., 62: 22, LEE Y.S. and LEE C.P.: Ulrasrucural pahological sudy of lef venricular myocardium in paiens wih isolaed rheumaic miral senosis wih normal or abnormal lef venricular funcion Jpn. Hear J. Jul., 31 (4): , BOLEN J.L., LOPES M.G., HARRISON D.C., ALDER- MAN E.L.: Analysis of lef venricular funcion in response o aferload changes in paiens wih miral senosis. Circulaion. Nov., 52 (5): , BONHOEFFER P., PIECHAUD J.F., e al.: miral dilaaion wih he mulirack sysem an alernaive approach, cahecardio Diagnosis, 36: , AL ZAIBAG M., RIBEIRO P.A., AL KASAB S. and AL FAGIH M.R.: Percuaneous double-balloon miral valvoomy for rheumaic miral-valve senosis. Lance. Apr., 5, 1 (8484): , YOSHIDA K., YOSHIKAWA J., YANAGIHARA K., KATO H., TAKAGI Y. and OKUMACHI F.: [Abnormal lef venricular configuraion and conracion in paiens wih miral senosis: a cross-secional echocardiographic sudy (auhor's ransl)] J. Cardiogr. Sep., 11 (3): , 1981.

9 Saeed Khaled, e al EL SAYED M., ANWAR M. and EL HAWARY S.: copariive sudy beween various mehods of percuanuous miral Commissuroomy Europe Hear J., 21: 310, CRIBIER A., ELTCHANINOFF H., KONING R., RATH P.C., ARORA R., IMAM A., EL-SAYED M., DANI S., DERUMEAUX G., BENICHOU J., TRON C., JAN- ORKAR S., PONTIER G. and LETAC B.: Percuaneous mechanical miral commissuroomy wih a newly designed meallic valvuloome: Immediae resuls of he iniial experience in 153 paiens Circulaion Feb., 16, 99 (6): 793-9, PAUL A.,TUCKER, JAMES, e al.: Balloon miral valvuloplasy clinical experience a he Texas Hear Insiue, 19 (4): , 1992.