transcatheter aortic valve replacement ( tavr ) is currently an alternative to surgical aortic valve replacement ( savr ) in high surgical risk patients with severe aortic stenosis ( as).1 ) although the experience of tavr is increasing in the medical communities worldwide , few cases of infective endocarditis ( ie ) after tavr has been reported . according to previous studies , ie after tavr ranges between 0% and 2.3%.2 ) at the current status , there are no clear guidelines as to how to diagnose or how to treat this complication,2 ) however nearly all of the patients undergo a very high - risk salvage surgical procedure for ie . here we report a patient with ie after tavr with some unique features that need discussion . a 76-year - old male ( preoperative logistic euroscore 9.92% ) underwent an uneventful tavr with a 29 mm corevalve for severe symptomatic as in january 2012 ( fig . 1 and 2 , supplementary movie 1 , 2 , 3 , 4 ) . furthermore , he suffered from ischemic heart disease which had been treated by percutaneous coronary intervention to mid - left anterior descending coronary artery 7 years before . although the patient 's logistic euroscore was relatively low , he and his family strongly preferred tavr than savr . before the procedure , transthoracic echocardiography demonstrated severe as ( peak / mean gradient 90/55 mmhg , aortic valve peak velocity 4.74 m / s , aortic valve area 0.73 cm by continuity equation ) with normal left ventricle ( lv ) function ( ejection fraction 69% ) and there was no pulmonary hypertension . he was discharged 7 days after the procedure with only mild paravalvular aortic regurgitation ( ar ) . on meticulous history taking , he had periodontitis , for which incision and drainage of the abscess was performed 1 month prior to admission at a nearby hospital . inflammatory markers including white blood cell count ( 19700/mm ) and c - reactive protein level ( 11.54 mg / dl ) were markedly elevated . 3a ) and electrocardiogram showed atrial fibrillation with rapid ventricular response and left bundle branch block ( fig . however , severe mitral regurgitation was noted just beneath the strut of the bioprosthesis ( fig . 4a , supplementary movie 5 ) . transesophageal echocardiography was performed without delay , which demonstrated a large mobile vegetation attached to the anterior mitral leaflet and severe mitral regurgitation due to multiple perforations of the mitral valve leaflet . abscess was also noted at the aortomitral continuity ( fig . 4b , supplementary movie 6 ) . first of all , the location of the implanted device and the paravalvular leakage may be a possible ' local ' risk factor for ie after tavr . in this case , the site of mitral regurgitation after ie was just located beneath the strut of the aortic bioprosthesis . therefore , although the device was implanted adequately according to the manufacturer 's recommendation , repetitive mechanical irritation by the bioprosthesis strut might have been a risk factor for ie.3 ) meanwhile some degree of paravalvular leak is common after tavr4 ) and considering that paravalvular leakage is a known risk factor for ie after tavr , the space between the bioprosthesis and the native aortic valve cusp might be a suitable nidus for pathogen accumulation during transient bacteremia.5 ) this case of our patient also demonstrated paravalvular leak associated with the aortic valve bioprosthesis . collectively , both paravalvular ar and irritation of the mitral valve by the stent struts may have equally contributed to endothelial damage and subsequent ie . one might also suggest that migration of the bioprosthesis may have contributed to the devastating result in our patient . indeed the inadequate positioning of the device initially or device migration thereafter may be a risk factor of ie . however the device was performed adequately in this patient with the device implanted 6 - 8 mm beneath the aortic annulus ( fig . moreover , there has been no case of device migration after successful device deployment6)7 ) and we also could not find definite evidence of device migration by echocardiography . besides , the degree of paravalvular ar had not changed at follow - up , which is difficult to imagine in the case of significant prosthesis migration . therefore , the possibility of ie caused by device migration may be dismissed in this case . according to the literature , ie after tavr seems to be very rare,8 ) but it is also a very serious complication,9 ) the majority of which requires surgical intervention.10)11)12)13 ) the diagnosis of ie after tavr might be particularly difficult and often delayed , therefore precise and early diagnosis is required . according to the duke criteria for diagnosis of ie , the major criteria are typical microorganisms consistent with ie and echocardiography findings positive for ie , such as vegetation , abscess or new partial dehiscence of prosthetic valve.14 ) because of the limited experience with ie associated with tavr , the following points remain to be discussed in the future . first , although streptococcus anginosus , which is a subtype of streptococcus viridans - the common pathogen for ie especially in native valve endocarditis - was identified in this patient , the common pathogen associated with ie in tavr is yet to be investigated . second , there are some structural differences between surgical valve and transcatheter valve . like our case , echocardiographic findings related to ie could be obscured by the metallic struts encircling the valve leaflets9 ) and there are no sutures that connect the bioprosthesis and the aortic annulus . therefore , valvular dehiscence may not be that common as in surgical valves and a more meticulous examination should be performed at multiple views during echocardiography for any evidence of vegetation or abscess pocket . therefore we anticipate that echocardiography may play a more critical and important role in these types of setting . this patient did not perform dental check - up before tavr , and underwent a dental procedure without antibiotics . currently , there are no guidelines for prophylaxis of ie after tavr.12 ) only a few case reports have suggested that the dental procedure and the lack of endocarditis prophylaxis may be a precipitating factor of ie in tavr setting.11)12 ) we also agree with our limited experience that dental procedure without antibiotics prophylaxis may be a predisposing factor for ie after tavr . furthermore considering this possibility , proper antibiotics before the dental procedure should be considered , just as a prosthetic cardiac valve replaced by surgery in the current guidelines.15 ) in conclusion , we report an interesting case of ie 1 month after successful tavr . the location of the vegetation and subsequent mitral regurgitation suggests that the local mechanical irritation by the valve strut and even mild paravalvular ar might play a possible role for ie initiation after tavr . also , antibiotics prophylaxis should be considered strongly in patients who have undergone tavr just like the patients who have had surgical valve replacement . data , preferably international , on this important issue should be gathered and analyzed in the future . movie 1 - 4 . transthoracic echocardiography images before ( movie 1 and 3 ) and after ( movie 2 and 4 ) transcatheter aortic valve replacement ( tavr ) . parasternal short - axis views of the aortic valve ( movie 3 and 4 ) . before tavr ( movie 1 and 3 ) . transesophageal echocardiography images showing the vegetation located just at the ventricular side of the aortic valve bioprosthesis with subsequent perforation of the anterior mitral valve .
recently , transcatheter aortic valve replacement ( tavr ) has emerged as an alternative for the treatment of severe symptomatic aortic stenosis patients . 
 although experience with tavr is increasing exponentially , few cases of post - tavr endocarditis are reported . 
 we present a case of 76-year - old man with infective endocarditis after tavr who was definitely diagnosed by echocardiography .