A devastating complication of Prosthetic Aortic Valve Infective Endocarditis; Aorto-ventricular fistula with periaortic abscess presenting with complete heart blockMohammad Sahebjam1, Mahboobeh Sheikh2*1Associate Professor of Cardiology, Department of Echocardiography, Tehran Heart Center, Cardiovascular diseases Research institute, Tehran University of Medical Sciences, Tehran, IranMail: msahebjam@sina.tums.ac.ir2*Assistant professor of Cardiology, Department of Cardiology, Zabol University of Medical sciences, Zabol, IranGmail: drmsh79@gmail.comPhone number: +9891232328041 first author.2*corresponding authorAbstractAortoventricular fistula (AVF) is an uncommon life-threatening condition that can arise after prosthetic valve endocarditis (PVE). In some cases, AVF may be associated with abscess formation, further complicating the condition. We present a case of a 71-year-old man with infective endocarditis of Aortic valve bioprosthesis with aorto-Left Ventricular Outflow Tract ( LVOT) fistula and complete Heart Block ( CHB) following periaortic abscess formation. unfortunately, He passed away before the urgent surgical timeline.Keywords: Infective Endocarditis, Prosthesis, Aortic Valve, Periaortic Abscess, Aorto-ventricular FistulaAortoventricular fistula (AVF) is a rare and lethal complication after prosthetic valve endocarditis (PVE). In PVE, AVF typically develops as a result of the destructive infection that erodes the tissue surrounding the prosthetic valve, leading to the formation of a tract or tunnel connecting the aorta to the adjacent cardiac structure. AVF may be associated with abscess formation. In prosthetic valve endocarditis, abscesses can form in the surrounding tissues, including the myocardium, aortic root, or other nearby structures. And also may destroy the electrical conduction system and lead to Complete Heart Block (CHB). Treatment of AVF includes prompt surgical intervention in addition to Antimicrobial administration.A 71-year-old man presented to the emergency department with complaints of fever, chills, fatigue, night sweat, and dizziness for several days. His medical history was coronary artery bypass graft surgery (CABG) and aortic valve replacement with a TRIFECTA bioprosthesis five months ago.On examination, the patient exhibited fever, bradycardia(HR=30-35 bpm), hypotension (BP=90/50 mmHg), and oxygen saturation of 93%. His electrocardiogram showed sinus rhythm, complete heart block with wide QRS complex (figure 5). Therefore temporary pacemaker was implanted. Laboratory findings showed leukocytosis 18.3×109/l; thrombocytopenia 50×109/l; anemia Hb 8.6/l, Increased ESR and CRP, and negative blood cultures.Three-dimensional Transoesophageal echocardiography revealed multiple mobile vegetations attached to the bioprosthetic aortic valve with significantly increased gradients, severe mixed transvalvular and paravalvular aortic insufficiency, increased thickness of aortic root and intervalvular fibrosa (30mm×16mm) with echo lucent area in favour of periaortic abscess( figure 3) which fistulated into left ventricular outflow tract (LVOT) from one side and Aortic root on the other side. (video 2, figure1-2)This fistulization made a canal-like pathway between LVOT and the aortic root with systolic expansion with turbulent flow from LVOT during systole and expansion with turbulent flow from the aortic root during diastole.(figure 4, video1,3 ) The patient received standard antimicrobial therapy and prepared for prompt reoperation, but his condition deteriorated with progressive multi-organ failure, and passed away before the surgery.DeclarationsEthical ApprovalWritten informed consent was obtained from the patient for publication of this case Imaging.Competing interestsThe authors declare that they have no competing interests associated with this publication.Authors’ contributionMSahebjam was the first author which was the main provider of the data and contributing in writing and editing the manuscript. Msheikh is the corresponding author and contributed in writing and editing the manuscript.FundingThe authors received no financial support for this article’s research, authorship, and publication.Availability of data and materialData are available in a repository and can be accessed using a unique identifier other than a DOI. The data underlying this article are available in the databank of Tehran heart center hospital and can be accessed with the deposition number. However, it must be kept private due to some reasons. First, to protect  the privacy of individual who participated in the study, it is also against the hospital rules and regulations; moreover, the primary language is Persian. Nevertheless, the data will be shared on reasonable request to the corresponding author.Aknowledgement: Not applicableReferencesVideo.1 Transesophageal Echocardiography (TEE) , the X-plane long-axis view of the aortic prosthesis revealing destructive bioprosthetic AV with the prosthesis rocking motion and significant thickening of intervalvular fibrosa (left ). Circumferential periaortic thickness with echo-free spaces, indicative of preaortic abscess formation. (right)Video 2. Transesophageal echocardiography(TEE) long axis view. Bidirectional flow through the fistulous tract with systolic flow toward the Aortic root and diastolic flow toward the Left Ventricular Outflow Tract (LVOT)Video 3. TEE-3D multi Vue