ASSESSMENT OF MITRAL VALVE FOR PTMC

Dr Satyam Rajvanshi

HISTORY

• Early in the development of percutaneous mitral and aortic balloon dilation, the technique was considered to be experimental, unproven, and even dangerous.

• However, many invasive cardiologists had similarly been sceptical when they heard of the Swiss physician Greuntzig's proposal of balloon dilation of coronary arteries.

Circulation Vol 82, No 2, August 1990

• The surprising success of balloon angioplasty (1982) made cardiologists receptive to the possibility that balloons could effectively treat valvular stenosis.

Circulation Vol 82, No 2, August 1990

• Case Series & case reports published from 1985-1988 after Inoue’s publication; Also Double balloon technique

• Because it was experimental, patients who were poor candidates for surgical valve replacement were those initially chosen for mitral balloon dilation – ELDERLY, SEVERELY DEFORMED VALVE, HEAVY VALVULAR CALCIFICATION

• Even in these patients, balloon dilation was suprisingly successful at times

• The impressive results of surgical commissurotomy relied in part on surgeons' "almost mystical ability to select (surgical) candidates”

Circulation Vol 82, No 2, August 1990

• Which valves might respond to balloon dilation seemed to cardiologists an unanswered question??

Br Heart J 1988;60:299-308

Circulation Vol 79 No 3, March 1989

Circulation Vol 82 No 3, August 1990

Predictive variables

• Factors assessed to predict optimal or suboptimal outcome

• Suboptimal – Any 1 or more• Final valve area < 1 cm2 / <1.5 cm2 in later studies• post-dilatation mean left atrial pressure > 10 mmHg• Change in area < 25% of the initial valve area in those

with a mitral valve area > 1 cm2 before procedure

Variables assessed in early studies

• Clinical– Age, Sex, Baseline Rhythm, NYHA class

• Echocardiographic– Structural features of MV and subvalvular

apparatus– MVA (Planimety)– LA size– Grade of MR

• Hemodynamic– MVA– TransMitral PG– CO– PVR– LVEDP

• Technical– Balloon used– Effective dilating area of balloon– Number of inflations

RESULTS

• Clinical– Age, Sex, Baseline Rhythm, NYHA class

• Echocardiographic– Structural features of MV and subvalvular

apparatus– LA size– MVA (Planimety) – Grade of MR

Surprisingly, more severe stenosis or smaller baseline valve area did not predict Suboptimal outcome; smaller MVA as likely as larger MVA to give suboptimal results

Age, AF, NYHA class - weak predictors

• Hemodynamic– MVA– TransMitral PG– CO– PVR– LVEDP

• Technical– Balloon used– Number of inflations– Effective balloon dilatation area (EBDA)

Flouroscopic Calcium alsoWeak predictor

• Strongest & best predictor of immediate hemodynamic optimal result

MITRAL VALVE STRUCTURE

SCORE

Most patients with a total echocardiographic score > 11 had a suboptimal result

Those with a score < 9 had an optimal result

The score failed to predict outcome in those with scores of 9 to 11

• Why 8?

• The sensitivity of the total echo score for predicting a "good" outcome - calculated for each score value - proportion of all patients with a "good" outcome who had scores equal to or less than that score value

• The specificity was the proportion of all patients with a suboptimal outcome who had a total echo score above that score value

Echo score relevance

• Higher EBDA and Sinus Rhythm are significant favourable predictors

• Baseline AF rhythm also independently predicts restenosis

• Upto 50% pts – MR grade increased by 1+; 50% of these – MR decreased by 1 grade in follow-up; 30% pts - MR grade increased by >1+

Score ≤8 ≥8

Immediate optimal result 88% 44%

NYHA class improvement 90% 56%

Re-stenosis at 2 yrs by Echo

<10% 70%

EVALUATION OF PATIENT

INDICATION

• SYMPTOMATIC NYHA II or more• MVA < 1.5 cm2 in a normal sized adult (or < 1 cm2 / m2) • Favourable valve morphology

• Reasonable (IIa) in– symptomatic patients in whom surgery carries high

risk for adverse events or outcomes, even when valve morphology is not ideal,• restenosis after a previous BMV or previous

commissurotomy who are unsuitable candidates for surgery because of very high risk – very old, frail patients; associated severe ischemic heart disease; pulmonary, renal, or neoplastic disease; • women of childbearing age in whom mitral valve

replacement is undesirable; • Pregnant women with MS.

CONTRAINDICATIONS

• MR > 2+

• Left atrial thrombus• Severe commisural calcification (Bicommisural

heavy – Grade 4 calcification)

IF INDICATED

• ECG • CHEST RADIOGRAPH• ECHOCARDIOGRAPHY

ECG

• LAE• RAE• RVH• Atrial arrhythmias

• P wave duration and P wave dispersion correlate with MS severity

Pacing Clin Electrophysiol 2008;31:1620-4

• RAD & RBBB presence correlates with MS severity

Cardiology 2006; 105:219-22

• Acute hemodynamic changes following BMV produce corresponding changes in ECG, mainly in P wave and QRS axis

Indian Heart J 1998;50:179-82

RADIOGRAPHY

CHEST RADIOGRAPHY

• LAE• Calcification• PVH• PAH

VENTRICULOGRAPHY

• MV doming and calcification

• MR severity

• Subvalvular disease (Atkins)Mitral-subvalvular distance (ES)/AoV-Apex distance (ED)<0.2 – Severe subvalvular disease

End-systole End-diastole

ECHOCARDIOGRAPHY

Parameters assessed

• Severity of MS• Pliability of valve (suitability)• MR• LA thrombus• IAS • Other ass. Valvular ds• PAH

M-mode

• DE amplitude more than 18 mm – pliable valve

• EF slope less than 20 mm/sec – Severe MS

MS severity by planimetry

• PSAX• MAX opening in mid diastole• Plane perpendicular to orifice• Lowest gain setting• Open commissures included• Avg 3 cycles in SR, 5-10 in AF

• Limitation– Gain– Calcification– Commissure– Plane

MV separation index < 0.8> 1.1

Valve mobility

• Wilkins grading 1-4• Reid grading 0-2 -- Extent of doming

Valve thickening

• < 4 mm normal• 5-8 mm – MILD• >8 mm – MARKED

• Valve thickness/post Aortic wall thickness<1.5 – Normal <2 – Mild 2-5 – Moderate >5 – Marked /Severe

Valve calcification

SubValve thickening

• PLAX• A4C/A2C

IAS

LA thombus

Scoring

• Wilkins• Reid (Br Heart J 1977;39:1088-92)

• Lung-Cormier (Antunes MJ, Acquired Heart valve ds, 1995)

• Padial (JACC 1996;27:1225-31)

• Massachusetts General Hospital (MGH)• Ain Shams (Echocardiography 2009; 26:119-27)

• RT3DE

Wilkins Score

Reid Score

Lung and Cormier score

Padial Score

• Significant MR post BMV– Uneven MV thickening– Severe subvalvular ds– Commisural calcification

Cutoff 10

Ain Shams

• Calcification– Leaflet margin – 2– Leaflet Body – 4– Commisure – 6

• Subvalvular thickening– Less than half - 4– More than half - 4– Full length - 6 Cutoff - 4

RT3DE

• Preprocedural MRDoes not predict success directlyBenefit of using larger balloon only in

absence of significant MR

• TEELA and LAA clotUnderestimates subvalvular ds

Scoring system problems

• Subjective, Semiquantitative• Echo diff of nodular fibrosis from calcium• Subvalve ds underestimation• Non inclusion of commisural calcium• Uneven distribution of pathology

• Combination of scores solves some of these problems

TAKE HOME MESSAGE

• BMV is feasible, safe, and successful, provided that proper assessment has been done pre-procedure

• Check Indications & Contraindications• Echo scoring – Combine scores, include

commisural calcium score• TEE to rule out LA clot esp in patients with AF• Periprocedural monitoring and follow-up is

essential