The role of computed tomography in the planning of transcatheter aortic valve implantation: a retrospective analysis in 200 procedures

Role of computed tomography in transcatheter replacement of 'other valves': a comprehensive review of preprocedural imaging

Transcatheter procedures for heart valve repair or replacement represent a valid alternative for treating patients who are inoperable or at a high risk for open-heart surgery. The transcatheter approach has become predominant over surgical intervention for aortic valve disease, but it is also increasingly utilized for diseases of the 'other valves', that is the mitral and, to a lesser extent, tricuspid and pulmonary valve. Preprocedural imaging is essential for planning the transcatheter intervention and computed tomography has become the main imaging modality by providing information that can guide the type of treatment and choice of device as well as predict outcome and prevent complications. In particular, preprocedural computed tomography is useful for providing anatomic details and simulating the effects of device implantation using 3D models. Transcatheter mitral valve replacement is indicated for the treatment of mitral regurgitation, either primary or secondary, and computed tomography is crucial for the success of the procedure. It allows evaluating the mitral valve apparatus, the surrounding structures and the left heart chambers, identifying the best access route and the landing zone and myocardial shelf, and predicting obstruction of the left ventricular outflow tract, which is the most frequent postprocedural complication. Tricuspid valve regurgitation with or without stenosis and pulmonary valve stenosis and regurgitation can also be treated using a transcatheter approach. Computer tomography provides information on the tricuspid and pulmonary valve apparatus, the structures that are spatially related to it and may be affected by the procedure, the right heart chambers and the right ventricular outflow tract.

Transcatheter aortic valve implantation in patients with unruptured aortic root pseudoaneurysm: an observational study

AIMS

Unruptured aortic root pseudoaneurysm (UARP) is a rare complication of aortic valve endocarditis. Infectious spread to the valvular annulus or myocardium can cause septic complications that manifest as wall thickening, and spontaneous abscess drainage leads to pseudoaneurysm formation. We report the first patient series in which transcatheter aortic valve implantation (TAVI) using a single valve-resolved aortic valvulopathy associated with UARP was performed.

METHODS

At our center, from December 2017 to October 2019, 138 patients underwent TAVI for aortic valve stenosis and/or regurgitation, 20 of whom (12 female patients, 8 male patients) had associated incidental UARP and were considered as our study population. The average age of these patients was 76.9 ± 5.2 years. All patients were assessed using preprocedural and postprocedural multimodality imaging, including transthoracic echocardiography, transesophageal echocardiography, and cardiac computed tomography angiography (CCTA).

RESULTS

In all cases, the final angiographic examination showed correct valve positioning with complete coverage of the false aneurysm. Post-TAVI CCTA showed presence of total or subtotal UARP thrombosis. The mean follow-up period was 17.5 months (12-23 months). During follow-up, imaging showed normal prosthetic valve function, no significant leakage (trace or mild), and complete UARP exclusion in all patients, without any complications.

CONCLUSION

In conclusion, percutaneous valve positioning can simultaneously solve pseudoaneurysm complications by excluding the sac and promoting thrombosis.

Stent deformation in a sutureless aortic valve bioprosthesis: a pilot observational analysis using imaging and three-dimensional modelling

OBJECTIVES

The goal of this analysis of the Perceval aortic bioprosthesis was to investigate the ovalization/deformation of the Perceval prosthesis stent after implantation and its propensity for cusp dysfunction, fluttering, fibrosis and blockage.

METHODS

Between August 2014 and May 2019, a total of 134 patients (52% female) underwent aortic valve replacement with the Perceval bioprosthesis. We reconstructed three-dimensional models of the Perceval stent using thorax computed tomography scans for 16 patients employing the software Mimics (Materialise NV, Leuven, Belgium) and analysed the ovality of the stents. Radial force (RF) measurements were performed to compare the stiffness of the Perceval bioprosthesis to that of other valves.

RESULTS

The three-dimensional reconstructions showed that all Perceval stents exhibited some degree of deformation and ovalization. Ovality in the annulus and commissure section of the Perceval stents ranged from 6.8% to 45% with mean values of 13.6% and 21.9%, respectively. The RF of the Perceval prosthesis was noticeably lower than that of the Edwards Intuity and several transcatheter aortic valve implantation devices. The stent adopted the preoperative shape of the aorta in the 2 patients for whom pre- and postoperative computed tomography data existed.

CONCLUSIONS

The Perceval bioprostheses were deformed to different degrees in all analysed cases. The comparably low RFs might be an explanation for the propensity towards this deformation, which can lead to fluttering, a reduction of the cusps' mobility. This condition could potentially result in fibrosis as well as increased transvalvular pressure gradients and might be the cause for the increase in lactate dehydrogenase and the decrease in platelet count.

Pseudoaneurysm of the aortic root following aortic valve endocarditis - a case with 2 rare life - threatening complications

Infective endocarditis can have peri-annular spread and involve the valvular annulus and adjacent cardiac structures, leading to tissue necrosis and peri-annular abscess. This process may cause pseudoaneurysm formation and other rare and potentially life-threatening complications, so their identification and correct diagnosis are crucial.

We describe a case of an 81-year-old woman, with a history of aortic valve replacement and worsening of symptoms, that presents at the imaging a pseudoaneurysm of the aortic root complicated at the same time by 2 life-threatening conditions: fistulization in the Right Ventricular Outflow Tract (RVOT) and the compression of Right Coronary Artery (RCA).

This case underlines the importance of imaging, especially Coronary Computed Tomography Angiography (CCTA), in the diagnosis and follow-up of infective endocarditis and its complications, especially in a patient not eligible for surgery.

Relationship between septo-valvular angle and risk of pacemaker implantation after transcatheter aortic valve implantation: a preliminary study

AIM

Pre-transcatheter aortic valve implantation (TAVI) computed tomography (CT) has proven to be crucial in identifying pre- and post-procedural predicting factors predisposing the onset of major arrhythmias that require permanent pacemaker (PPM) implantation caused by the compressive effects of the prostheses on the conduction system at the membranous septum (MS) and the muscular crest of the interventricular septum.Our analysis aims to verify if the pre-TAVI assessment of the angle between the MS and the aortic annulus (SVA) might be a predictive factor for the onset of arrhythmias that requires PPM.

METHODS

Two cardiovascular specialist radiologists retrospectively and double-blind evaluated a randomized list of preprocedural CT of 57 patients who underwent TAVI with a self-expandable valve from April 2019 to February 2020. Two anatomical features were measured by readers: width of the SVA and MS length (MSL).

RESULTS

A PPM was implanted in 18 patients (31%) after the procedure. There was no significant difference in the anatomical measurements performed between the two observers, regarding both anatomical measurements (intraclass correlation coefficient was 0.944 for the SVA and 0.774 for the MSL]. Receiver-operating characteristic curves (ROC) performed for both measurements have documented: for the SVA sensitivity 94% and Negative predictive value (NPV) 96% (area under the curve: 0.77; 95% confidence interval 0.66-0.90). The MSL ROC was not significant. The mean SVA value stratified for patients who did not undergo PPM implantation and patients who did resulted as significant (P < 0.005).

CONCLUSION

Measurement of the SVA performed in preprocedural CT scans has proven to be related to the onset of major arrhythmias after TAVI requiring permanent pacemaker implantation with high sensitivity (94%) and NPV (96%).

A rare case of a giant circumflex coronary artery aneurysm 10 years after bentall surgery

In this paper, we describe a rare case of coronary artery aneurysms occasionally found on a pre interventional Coronary Computed Tomography Angiography performed on a 67-year-old man with a history of aneurysm of the ascending aorta previously treated with Bentall surgery, who arrived at our hospital to have a percutaneous valve-in-valve implantation procedure. Even though the patient was considered not eligible for the procedure, due to his many comorbidities, and conservatively managed, at 1-year followup his angiographic condition remained stable.

Role of computed tomography in transcatheter aortic valve implantation and valve-in-valve implantation: complete review of preprocedural and postprocedural imaging

: Since 2002, transcatheter aortic valve implantation (TAVI) has revolutionized the treatment and prognosis of patients with aortic stenosis. A preprocedural assessment of the patient is vital for achieving optimal outcomes from the procedure. Retrospective ECG-gated cardiac computed tomography (CT) today it is the gold-standard imaging technique that provides three-dimensional images of the heart, thus allowing a rapid and complete evaluation of the morphology of the valve, ascending aorta, coronary arteries, peripheral access vessels, and prognostic factors, and also provides preprocedural coplanar fluoroscopic angle prediction to obtain complete assessment of the patient. The most relevant dimension in preprocedural planning of TAVI is the aortic annulus, which can determine the choice of prosthesis size. CT is also essential to identify patients with increased anatomical risk for coronary artery occlusion in Valve in Valve (ViV) procedures.Moreover, CT is very useful in the evaluation of late complications, such as leakage, thrombosis and displacements. At present, CT is the cornerstone imaging modality for the extensive and thorough work-up required for planning and performing each TAVI procedure, to achieve optimal outcomes. Both the CT procedure and analysis should be performed by trained and experienced personnel, with a radiological background and a deep understanding of the TAVI procedure, in close collaboration with the implantation team. An accurate pre-TAVI CT and post-processing for the evaluation of all the points recommended in this review allow a complete planning for the choice of the valve dimensions and type (balloon or self-expandable) and of the best percutaneous access.