Andersons pediatric cardiology 1467

Percutaneous Strategies for Mitral and Aortic Valve Disease Percutaneous Management of Mitral Stenosis Percutaneous mitral balloon valvuloplasty (PMBV) has evolved as the procedure of choice for treating severe MS in patients with suitable anatomy Mid- and long-term results are comparable to open commissurotomy, with the advantage of being a less invasive technique As with other structural and valvar interventions, outcomes are heavily dependent on proper patient selection and operator experience Indications for Percutaneous Mitral Balloon Valvuloplasty PMBV is currently indicated in symptomatic patients with favorable anatomy and an MV area of less than 1.5 cm2 or an indexed area of less than 0.6 cm2/m2 PMBV may also be considered in asymptomatic patients with very severe MS (mitral valve area 8 to 10 throughout much of muscles mm) the leaflet tissue MV, Mitral valve Modified from Wilkins GT, Weyman AE, Abascal VM, et al Percutaneous balloon dilatation of the mitral valve: an analysis of echocardiographic variables related to outcome and the mechanism of dilatation Br Heart J 1988;60(4):299–308 All patients must undergo transesophageal echocardiography (TEE) prior to the procedure to rule out the presence of a left atrial or left atrial appendage thrombus TEE may also be useful in patients with poor transthoracic windows Contraindications to Percutaneous Mitral Balloon Valvuloplasty Absolute contraindications to PMBV include moderate or severe MR, the presence of a left atrial thrombus (free-floating or adherent to the interatrial septum), bicommissural calcification, and the need for surgery on another valve The presence of a left atrial appendage thrombus warrants anticoagulation for 3 months followed by reevaluation by TEE Persistence of a left atrial appendage thrombus has traditionally been regarded as a contraindication to the procedure; however, a few reports suggest that PMBV can safely be performed by highly experienced operators in patients with adherent organized thrombi limited to the left atrial appendage.65,66 Mechanism of Percutaneous Mitral Balloon Valvuloplasty and Technical Considerations Three main modalities currently exist for percutaneous management of MS, all of which depend on splitting of the commissures The procedure is considered successful when the postvalvotomy valve area increases to more than 1 cm2/m2 The most commonly used is the Inoue technique, first introduced by Kanji Inoue in 1982.67 The standard Inoue technique depends on antegrade access into the MV orifice via a transseptal puncture Retrograde (transaortic) access has been reported in a limited number of cases but is rarely used today The balloon is manufactured from two latex layers between which is a polyester micromesh An extra latex band is placed around the center of the balloon; a stainless steel tube is used to stretch the balloon prior to insertion and a 14-Fr tapered dilator then enlarges the interatrial opening Owing to the different elastic properties of the proximal, distal, and central parts of the balloon, it exhibits four different inflation stages, which enable snug fitting across the valve before gradual dilatation (Fig 55.11)