Preliminary Reports . . . works in progress

Transjugular Approach toTransseptal Balloon MitralValvuloplasty

George Joseph, * MD, DM, Dibya K. Baruah, MD, DM,Sajy V. Kuruttukulam, MD, DM,Sunil Thomas Chandy, MD, DM,and Shanker Krishnaswami, MD, DM, FACC

The feasibility of a transjugular approach to septal puncture andInoue-balloon mitral valvuloplasty (BMV) was studied in 20patients with severe mitral stenosis and varying degrees ofanatomic atrial distortion. Left atrial entry by transjugular septalpuncture was achieved without difficulty and BMV completed inall patients. In all of 16 patients who had high septal punctures,crossing the mitral valve with the Inoue-balloon was consis-tently simple and quick. In one patient, septal dilation after veryhigh septal puncture led to a tear extending to the atrial free wall,resulting in cardiac tamponade requiring surgery. Another pa-tient developed severe mitral regurgitation after BMV and re-quired mitral valve replacement. Excellent results were obtainedin 16 patients. The transjugular approach simplifies BMV proce-dure significantly in patients with distorted atrial anatomy andallows rapid patient mobilization. Its safety and efficacy need tobe established in larger studies. Cathet. Cardiovasc. Diagn.42:219–226, 1997. r 1997 Wiley-Liss, Inc.

Key words: mitral valve stenosis; balloon dilation; heart catheter-ization; heart septum; jugular veins

INTRODUCTION

Balloon mitral valvuloplasty (BMV) is an establishedmethod of treatment of rheumatic mitral stenosis [1–5].Short procedure times and successful outcomes can beanticipated in most patients undergoing BMV. However,difficulties may be encountered when the atrial anatomyis distorted or when the site of septal puncture isinappropriate, leading to prolonged procedures or techni-cal failures [6–9]. Common to all transvenous BMVtechniques is the need for catheters introduced via thefemoral vein to bend almost 180 degrees after traversing

the atrial septum to cross the mitral valve. These cathetersalso have to simultaneously curve anteriorly and conformto the widely varying anatomic distortion of the heart. Wereasoned that septal puncture by a transjugular approachcould provide a more direct route to the mitral valve,without catheters having to bend over backward to crossthe mitral valve. This approach could potentially reducethe critical dependence, of procedural complexity andoutcome, on the site of septal puncture selected. Thefeasibility of such an approach to BMV was investigatedin 20 patients with severe mitral stenosis and varyingdegrees of anatomic atrial distortion, which could poten-tially cause technical difficulties during transfemoraltransseptal BMV.

METHODS

Patients selected had one or more features frequentlyassociated with the presence of anatomic atrial distortion:large left atrium (.45 mm in parasternal long axisechocardiography), restenosis after previous surgicalclosed mitral valvotomy, high mitral valve morphologicscore (.8), or atrial fibrillation (Table I). Echocardiogra-phy was used before and after BMV to determine mitralvalve morphologic score [10], area [11], and regurgitation[12].

Patients were brought to the catheterization laboratoryin a fasting state after prior informed consent andpremedication. The right internal jugular vein was cannu-lated percutaneously and right heart catheterization andoximetry run were performed. In all patients, a pulmo-nary angiogram was performed, in 45-degree right ante-rior oblique projection, with levophase imaging of the leftatrium. The right brachial artery was cannulated percuta-neously and a 5 French pigtail catheter was positioned inthe noncoronary aortic sinus as a landmark duringtransseptal puncture. Echocardiographic guidance wasnot utilized during the procedure.

Transjugular Septal Puncture

For transjugular septal punctures, the curve of thetransseptal needle was increased to avoid oblique passageof the needle through the septum (Fig. 1). A 0.032-inchguidewire was used to exchange a catheter positioned inthe inferior vena cava for a 8F MullinsTM transseptalsheath and dilator, into which the BrockenbroughTM

transseptal needle was introduced (both from USCIdivision, C.R. Bard, Tewksbury, MA). The assembly was

Department of Cardiology, Christian Medical College Hospital,Vellore, India

*Correspondence to: Dr. George Joseph, Department of Cardiology,Christian Medical College Hospital, Vellore, India.

Received 13 January 1997; Revision accepted 9 April 1997

Catheterization and Cardiovascular Diagnosis 42:219–226 (1997)

r 1997 Wiley-Liss, Inc.

then withdrawn into the right atrium under continuousfluoroscopic monitoring.

Fluoroscopy during transseptal puncture was restrictedto the 45-degree right anterior oblique view, wherein theseptum is viewed en face, allowing maximal separation ofthe anterior aorta and posterior heart border [13]. Thelevophase left atrial image was kept frozen on an adjacentscreen for ready reference. In the first four cases, the siteof puncture was at the fossa ovalis, below the level of theaortic valve (site 1 in Figs. 2 and 3A). In the next eightprocedures, a very high site of septal puncture was chosen(site 2 in Figs. 2 and 3A). This site was 1 cm below theroof of the left atrium and midway between imaginaryvertical lines passing through the pigtail catheter tip at theaortic valve and the anterior border of the thoracic spine,viewed in the 45-degree right anterior oblique view. In allsubsequent cases, the site chosen was 2 cm (height of onethoracic vertebral body) below the roof of the left atrium(site 3 in Figs. 2 and 3A).

After confirming needle entry into the left atrium (Fig.3B), the transseptal set was advanced across the atrialseptum and a curved 0.025-inch wire introduced into theleft atrium. Heparin 5,000 units was administered at thistime. The skin entry site and septum were dilated using a

14 French long dilator or 8-mm angioplasty balloon earlyin the series. In subsequent procedures, a 30-cm-long 14French sheath with hemostatic valve (Cook, Blooming-ton, IN) was advanced into the left atrium.

Mitral Valve Dilation

The mitral valve was dilated using the Inoue-balloon inall 20 patients. In the first four patients, in whom septalpuncture was below the level of the aortic valve, anover-the-wire technique using a 0.025-inch guide wirewas necessary to guide the Inoue-balloon across themitral valve. In subsequent cases, a ‘‘S’’-shaped styletwith anterior curvature of the tip (made by reshaping theconventional ‘‘U’’-shaped stylet) was used to direct theInoue-balloon across the mitral valve as follows: theballoon-catheter, with stylet within, is retracted androtated clockwise to be aligned with the apex-mitral valveaxis. Characteristic bobbing of the partially inflatedballoon will now be evident (Fig. 4A,B). The catheter andstylet can now be advanced as a unit across the mitralvalve during diastole (Fig. 4C,D).

Balloon dilation technique (Fig. 5) was as described forthe transfemoral approach [1,14]. Balloon catheter sizeand maximum diameter of dilation were determined

TABLE I. Patient Characteristics and Results of Transjugular BMV *

No.

AgeandSex CR

LASize(mm)

PastCMV

MitralValveScore

MVCa

Level ofSeptal

Puncture

Mean PAPressure(mm Hg)Pre/Post

Mean LAPressure(mm Hg)Pre/Post

MitralGradient(mm Hg)Pre/Post

Valve Area(cm2)

Pre/Post

MRGrade

Pre/Post Complications

1 30M SR 61 No 7 0 Low 62 32 48 12 26 3 0.75 2.00 0 0 Transient AV block2 35M SR 48 No 7 0 Low 26 14 16 6 15 3 0.92 2.24 1 1 —3 29F SR 62 Yes 9 2 Low 69 35 32 8 17 1 0.81 2.86 0 1 —4 36F SR 47 Yes 9 1 Low 31 18 23 9 12 3 0.90 1.66 0 0 Absent radial pulse5 31F SR 32 Yes 8 1 Very high 18 18 19 6 14 1 0.74 2.12 0 0 —6 42M AF 45 Yes 8 1 Very high 50 26 34 13 26 1 0.89 2.27 0 0 Air embolism7 39M SR 48 Yes 8 1 Very high 45 30 34 10 23 1 0.90 2.18 0 0 —8 41M SR 41 No 9 2 Very high 31 20 31 11 27 1 0.88 2.10 0 0 —9 17F SR 58 No 8 1 Very high 38 22 30 12 19 2 0.73 1.97 1 1 —

10 27M SR 56 No 6 0 Very high 47 21 38 15 19 1 1.04 2.04 0 1 —11 31M SR 58 No 5 0 Very high 25 20 31 9 17 2 0.85 2.06 0 0 —12 40F SR 59 No 7 0 Very high 34 17 23 8 16 1 0.83 1.98 0 0 Tamponade, surgery13 41F SR 46 No 9 1 High 60 89 30 38 25 1 0.66 2.00 0 3 Severe MR, MVR14 29M SR 33 Yes 11 2 High 45 30 33 16 23 6 0.81 1.40 0 0 —15 45F SR 52 No 7 0 High 17 14 22 4 15 2 0.82 1.82 0 0 —16 32F SR 40 Yes 9 2 High 38 22 23 5 18 2 0.94 1.76 1 1 —17 23M SR 47 No 9 2 High 64 17 34 8 19 1 0.73 2.50 0 0 —18 40M SR 50 No 8 1 High 52 23 38 9 16 1 0.85 1.76 0 0 —19 37M AF 60 No 10 3 High 21 29 17 13 14 6 0.82 1.30 0 2 —20 38M SR 50 Yes 8 0 High 30 26 22 16 17 3 0.67 1.76 0 1 —

m 34 49 40 26 29 11 19 2 0.83 1.96SD 7 9 16 16 8 7 4 2 0.09 0.37P 0.001 0.000 0.000 0.000

*Abbreviations: BMV, balloon mitral valvuloplasty; CR, cardiac rhythm; LA, left atrium; CMV, closed mitral valvotomy; MV Ca, mitral valve calcium onechocardiography; PA, pulmonary artery; LA, left atrium; Pre, pre-BMV; Post, post-BMV; MR grade, mitral regurgitation grade on echocardiography(1 5 mild, 2 5 moderate, 35 severe); SR, sinus rhythm; AF, atrial fibrillation; AV, atrioventricular; MVR, mitral valve replacement; m, mean; SD,standard deviation;P, probability value derived by comparison of pre-BMV and post-BMV data using tests of significance.

220 Joseph et al.

using a formula based on body height. Incrementaldilations were performed, starting at a diameter 2–4 mmless than the maximum allowed. Pressures were recordedafter each dilation and oximetry run repeated aftercompletion of the procedure. Sheaths were removedimmediately and hemostasis achieved by manual pres-sure. Patients were able to sit up straightaway and weredischarged after 24 hr.

RESULTS

Left atrial entry by transjugular septal puncture wasachieved without difficulty in all patients despite theunfamiliar approach. The tactile sensations experiencedduring transjugular high septal punctures are similar tothose in conventional transfemoral septal punctures. Theresistance to puncture and dilation in the high atrial eptumis not different from that in the low atrial septum provided

the needle traverses the high septum perpendicularly.Oblique passage through the high septum results ingreater resistance to subsequent passage of the 14 Frenchdilator and could potentially result in damage to theseptum. In such situations, the puncture was repeatedmore perpendicularly, after increasing the curvature ofthe needle.

Crossing the mitral valve with the Inoue-balloon waseasy in all cases in which the high atrial septum waspunctured (cases 5–20). However, this finding is not thecase if the septum is punctured below the level of theaortic valve (cases 1–4), and results in a disadvantageouscurve of catheter within the left atrium. Once across themitral valve with the Inoue-balloon, dilation of the valvewas uniformly easy in all 20 cases of the series. Therelatively straight path of the Inoue-balloon catheter tothe mitral valve makes control over balloon positioneasier than in the transfemoral technique. The mean

Fig. 1. Increased curvature given to needle used in transjugular septal puncture (1) comparedwith standard curvature of needle used in transfemoral septal puncture (2).

Transjugular Transseptal Mitral Valvuloplasty 221

mitral valve area increased from 0.836 0.09 cm2 to1.966 0.37 cm2 (P 5 0.000) (Table I). Significant fall inpulmonary artery pressure, left atrial pressure and mitralvalve gradient were noted post-BMV. Suboptimal results(post-BMV mitral valve area,1.5 cm2) were obtained intwo patients who had extremely deformed mitral valves(mitral valve morphologic scores of 11 and 10, respec-tively). Step-up of 8 and 4% were seen in the first twocases of this series, respectively, on post-BMV right heartoximetry. Pulmonary/systemic blood flow ratio (Qp/Qs)was 1.55:1 in case 1 and insignificant in case 2. In bothcases, 8-mm-diameter angioplasty balloons had beenused for additional septal dilation. No step-up was seen insubsequent cases in which 30-cm-long 14 French sheathswith hemostatic valves were introduced from the skinpuncture site to the left atrium. This method obviates theneed for further dilation of the septum, thus reducingpost-BMV left-to-right shunting. In addition, this sheathallows smooth entry of the Inoue-balloon catheter into theleft atrium while minimizing patient discomfort. Allpatients tolerated the procedure well and most weredischarged within 24 hr.

Complications

There were two major complications (Table II). In onepatient, proximity of the very high septal puncture site tothe right atrial free wall and the superior vena cava led toa tear extending into these structures when the atrialseptum was dilated, resulting in cardiac tamponade.Another patient with severe subvalvar disease developedsevere mitral regurgitation, and required emergent mitralvalve replacement surgery. Six hours after surgery, thepatient developed recurrent ventricular arrhythmias anddied. The Starr-Edwards valve used was probably toolarge for the small left ventricle, and postoperativecatecholamine infusion and hypokalemia might havecontributed to the late onset of arrhythmia.

Minor complications that occurred are detailed inTable II. Pulmonary air embolism, seen in one of theinitial patients, did not recur after the introduction of 14French sheaths with hemostatic valves. There were nocerebrovascular accidents, embolic events, endocarditis,or skin entry site complications.

DISCUSSION

Transjugular high septal puncture offers a more directapproach to the mitral valve and makes crossing themitral valve consistently simple and quick. A highpuncture site ensured smooth completion of the BMVprocedure in all patients despite wide variation in degreeof anatomic atrial distortion. Fine tuning the site ofpuncture to suit individual variations is not necessary aslong as the high atrial septum is punctured with anadequate margin of safety above. In contrast, proceduralcomplexity and outcome of conventional transvenousBMV are highly dependent on the site of septal punctureselected, especially in patients with distorted atrialanatomy. Considerable operator experience is required toselect appropriate puncture sites consistently. After leftatrial entry, various complex maneuvers are often re-quired to cross the mitral valve [15].

The transjugular approach to BMV offers several otheradvantages. Traction on the atrial septum during mitralvalve dilation is less than in transfemoral BMV becausethe angle involved is less acute. Also, because the septumis punctured away from the fossa ovalis, the size of theseptal defect and magnitude of the left-to-right shuntproduced will be less as stretched tissues of thick atrialseptum tend to fall back into place. Inadvertent entry ofthe catheter into the left atrial appendage and dislodge-ment of clots is unlikely with this technique because thecatheter tends to lie in the inferior aspect of the left atriumand does not point upward during manipulations. Be-cause the groin is not used in this technique, the patient isable to sit up immediately after the procedure andambulate shortly thereafter, reducing patient discomfort.

Fig. 2. Levophase of pulmonary angiogram (45-degree rightanterior oblique projection) showing opacification of a large leftatrium. A pigtail catheter is in the noncoronary aortic sinus.Numbers indicate possible sites of transjugular septal punc-ture: (1) low, (2) very high, (3) high.

222 Joseph et al.

BMV can now be offered on an outpatient basis inselected patients. Thrombosed femoral veins, inferiorvena caval webs or filters and azygous continuation of theinferior vena cava do not impose restrictions on thetransjugular technique. In pregnant patients undergoingBMV, fluoroscopy over the abdomen will not be requiredat all if the transjugular approach is used. Lead aprons canbe wrapped completely around the abdomen and pelviswithout the groin having to be kept exposed. The patientcan flex the hip and knee during the procedure and reduceback ache and other discomforts associated with lyingimmobile for a length of time.

The safety and efficacy of transjugular BMV need to beestablished in larger studies. Of the two major complica-tions that occurred in this series, cardiac tamponaderesulting from atrial tear can be directly attributed to thetransjugular septal puncture. Now that a greater margin ofsafety is ensured above the site of puncture, this complica-tion should not recur. Importantly, crossing the mitralvalve with the Inoue-balloon was just as easy with thegreater margin of safety (high punctures) as without (veryhigh punctures). Severe mitral regurgitation is a problemwith any BMV technique, especially in patients withhighly deformed valves, and cannot be attributed to thetransjugular approach per se. A more gradual step-wisedilation of the mitral valve [15,16], and acceptance ofsome residual gradient [14], may reduce incidence of thiscomplication. Occurrence of significant complications is

not unexpected when a new technique or approach isbeing developed. Analysis of the complications seen inthis study indicates that these can largely be avoided byappropriate modification of equipment and technique. Aswith any other invasive procedure, individual operatorswill have to go through a learning phase when they startusing this technique. However, with further refinement ofthis technique and awareness of its pitfalls, the learningphase for new operators should be much smoother.

The conventional equipment for transseptal punctureand BMV is too long and unwieldy for the transjugularBMV technique. Much shorter (30-cm-long) transseptalsets and valvuloplasty balloon catheters will make theprocedure easier while reducing the working field consid-erably. Shorter catheter lengths will also allow more rapidinflation and deflation of balloons, because resistance toflow is proportional to the length of the catheter. Thisrefinement may be especially beneficial in bifoil balloonsthat inflate slowly [17]. Operators work closer to thex-ray source when using the transjugular techniquecompared with the transfemoral technique, leading togreater radiation exposure. However, this increase may beoffset by shorter procedure times in the long run, oncetransjugular equipment and technique are perfected.

Transjugular septal puncture may have other applica-tions. It has already been used to a very limited extent fordiagnostic left heart studies in situations where transfemo-ral access via the inferior vena cava was not possible

Fig. 3. A: Levophase of pulmonary angiogram. Arrows outlinethe left atrial roof. Numbers indicate possible sites of transjugu-lar septal puncture: (1) low, (2) very high, (3) high. B: Contrastinjection into the left atrium after needle puncture of the high

septum at site 3 (horizontal arrows) in the same patient. Verticalarrows outline the floor of the left atrium. Both pictures are in45-degree right anterior oblique projection.

Transjugular Transseptal Mitral Valvuloplasty 223

[Endrys J, personal communication]. It may be advanta-geous in transvenous aortic valvuloplasty because theballoon catheter can be much shorter and needs to bendonly 180 degrees within the heart to reach the aorticvalve, compared with almost 360 degrees in the transfemo-ral transvenous technique [18]. Transjugular septal punc-ture may find application in cardiac electrophysiologybecause it offers a more direct approach to the mitral

annulus, left ventricle, and inferior aspect of the leftatrium.

CONCLUSION

In conclusion, transjugular high septal puncture andBMV are feasible and relatively simple to perform. Thisapproach offers a more direct route to the mitral valve and

Fig. 4. A,B: To-and-fro movement of the Inoue-balloon catheter(with deflecting stylet advanced to the tip) between these twopositions indicates proximity to and coaxial alignment with themitral valve. C,D: Advancement of the catheter and stylet as a

unit in diastole (position B) will cause it to cross the mitral valveand enter the left ventricle. All pictures are in 30-degree rightanterior oblique projection.

224 Joseph et al.

Fig. 5. Inoue-balloon mitral valve dilation by transjugular high transseptal approach (straightanteroposterior projection). A: Waist on balloon produced by the stenotic valve. B: Fullexpansion of the balloon.

TABLE II. Complications of Transjugular Mitral Valvuloplasty *

CaseNo. Complication Time of Onset Mechanism Management Outcome Prevention

Major Complications12 Cardiac tamponade 10 min after comple-

tion of mitral valvedilation

Tear extending to theSVC–RA junctionafter dilation of thevery high atrialseptum

Surgical explorationand ligation of tear

Full recovery Increase margin ofsafety above highseptal puncture siteto 2 cm

13 Severe mitral regurgi-tation

After mitral valve dila-tion

Tear in deformed valvewith severe sub-valvar disease

Mitral valve replace-ment surgery

Postoperative death Gradual step-wise dila-tion, acceptance ofresidual gradient

Minor Complications1 Transient complete

heart block withjunctional escaperhythm

Before septal puncture Entry of transseptal setinto right ventricleduring withdrawalfrom IVC to RA

No treatment required Spontaneouslyreverted to sinusrhythm

Direct transseptal settoward RA free wallduring withdrawalto RA

4 Absent radial pulse After brachial arterysheath removal

Thrombus formation Intravenous heparin Rapid digital capillaryrefill

Clean puncture, peri-odic flush withheparinised saline

6 Asymptomatic pulmo-nary air embolism

During the procedure Air entry throughwidely dilated skinpuncture site keptopen by indwellingcatheter

Aspiration throughlarge bore catheter

No sequelae Use of 14 Frenchsheaths

*Abbreviations: SVC, superior vena cava; RA, right atrium; IVC, inferior vena cava.

simplifies the BMV procedure in patients with distortedatrial anatomy. The complications seen in this prelimi-nary study can be largely avoided by appropriate modifi-cation of equipment and technique. This technique islikely to find more applications and yield other benefits,but first its safety and efficacy need to be established inlarger studies.

ACKNOWLEDGMENTS

We wish to thank John K. Murthy, Lewis SampathKumar, Glory Doss, Anne Priyalatha, Sheeba Oommen,and Sheela D. for technical support in the cardiaccatheterization laboratory; V. Sitapathy and S. Umakanthfor photographic assistance; and Meenakshi M. for secre-tarial help.

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