Faculty Bibliography

AIMS: To determine the diagnostic information contained in cardiac pulsatile pressure waves as expressed in the Doppler signals recorded over the right lung. METHODS AND RESULTS: The pulsatile characteristics of the pulmonary vascular system were studied by means of the novel pulse Doppler technology in 38 control volunteers, 31 patients with atrial fibrillation (AF) and 7 patients with atrial flutter. The Doppler velocity waveforms recorded were interpreted in relation to the cardiac cycle mechanical events that generate them: Ventricular systole (S), diastole (D) and presystolic left atrial contraction (A). It was demonstrated that in all cases of AF, wave-A was absent. With longer diastole a high frequency velocity waves were visible. It is assumed that they represent the atrial mechanical fibrillation. In the patients with atrial flutter, the single A-wave was replaced by a waveform termed F, the frequency of which exactly matched that of the flutter wave on the ECG. The F-wave had both a positive and negative component. CONCLUSION: The lung Doppler signals contain distinct signatures typical of arrhythmias such as AF and atrial flutter that can be used for both diagnosis and to gain insight into the nature of the phenomena.

AIMS: Transcatheter techniques can theoretically be applied to the treatment of para-annular ring (PAR) leaks. Little is known about their potential application and resultant complications in such cases. We describe the first-in-man percutaneous transapical-transseptal Melody valve-in-ring (ViR) implantation after a complication from percutaneous PAR leak closure. METHODS AND RESULTS: A 49-year-old woman, at high operative risk, presented with congestive heart failure secondary to severe para-ring/extravalvular regurgitation two months after bypass surgery and mitral ring annuloplasty. Successful percutaneous closure of the leak was performed using an AMPLATZER Vascular Plug IV. One month later, she developed haemolysis with severe PAR regurgitation, through and around the device. After device retrieval and placement of an AMPLATZER Muscular VSD occluder, the patient developed severe intravalvular regurgitation. Completely percutaneous, transseptal delivery of a Melody ViR was performed over a transapical-transseptal, arteriovenous rail. Echocardiography revealed trivial residual regurgitation through the implanted valve with mild transvalvular gradients. CONCLUSIONS: Percutaneous closure of mitral PAR leaks after ring annuloplasty in the high-risk patient is feasible (proof-of-concept), particularly when the leak is para-ring/extravalvular. Potential complications include severe intravalvular mitral regurgitation caused by disruption of the mitral apparatus and/or ring deformation during device deployment, which can be successfully treated via percutaneous transapical-transseptal ViR implantation.

Percutaneous transapical access provides a direct route to many cardiac structures difficult to reach with conventional interventional approaches. With recent developments of new technologies in structural heart disease, there has been an increasing interest in the use of transapical access for cardiac interventions. Meticulous planning, careful access and closure techniques are essential. Development of novel imaging technologies and dedicated closure devices are warranted to allow a greater number of operators to successfully adopt percutaneous transapical access and further reduce complication rates. This article is an overview of the current status and utility of percutaneous transapical access with focus on multimodality imaging, technique and potential complications of this approach.

BACKGROUND: Aortic atherosclerosis is a risk factor for cerebrovascular events. Two-dimensional transesophageal echocardiographic quantification of descending aortic plaques is time-consuming and underestimates plaque burden. The aim of this study was to assess the feasibility and accuracy of a novel semiautomated program that uses three-dimensional (3D) transesophageal echocardiography to identify and quantify aortic plaque severity as determined by plaque thickness, volume, and number. The relationship between maximum plaque thickness and volume was also examined. METHODS: Descending aortic 3D transesophageal echocardiographic images from 58 patients were analyzed for plaque thickness, volume, and number using semiautomated custom software. The reference standard was manual assessment by an expert reader using 3D multiplanar reconstructions. Agreement and kappa values were calculated to determine the program's accuracy against the reference standard. Correlation and bias were examined using linear regression and Bland-Altman statistics. Pearson's correlation was used to examine the relationship between maximum plaque thickness and volume. RESULTS: Analysis was possible in all patients. Overall agreement for the absolute presence or absence of plaque per patient was 95%. Agreement regarding the number of plaques per patient and plaque severity was high at 95% and 85%, respectively. Plaque volume was slightly underestimated by the program compared with manual measurements. The correlation between plaque thickness and volume was 0.56. CONCLUSIONS: The results of this study demonstrate that semiautomated plaque analysis of 3D transesophageal echocardiographic descending aortic data sets is feasible and accurate in determining plaque severity as measured by plaque thickness, volume, and number. This methodology allows the standardization of plaque quantification, which will improve its utility in clinical trials. A greater understanding of the importance of plaque thickness versus volume is needed.

Left ventricular pseudoaneurysm and ventricular septal defect are rare but devastating complications of myocardial infarction. With medical treatment alone, the majority of patients will die from these complications. Until recently, the recommended treatment was surgical closure. These surgeries carried extreme risk due to abnormal hemodynamics, necrotic substrates and the comorbidities of these patients. Recently, trans-catheter closure was shown to be an acceptable alternative to open surgical intervention. 3D echocardiography identifies the location, size, and shape of the defect and can assess, guide, and follow up the closure procedure.

OBJECTIVES: The aim of this proof-of-principle study is to validate the accuracy of fusion imaging for percutaneous transapical access (TA). BACKGROUND: Structural heart disease interventions, including TA, are commonly obtained under fluoroscopic guidance, which lacks important spatial information. Computed tomographic angiography (CTA)-fluoroscopy fusion imaging can provide the 3-dimensional information necessary for improved accuracy in planning and guidance of these interventions. METHODS: Twenty consecutive patients scheduled for percutaneous left ventricular puncture and device closure using CTA-fluoroscopy fusion guidance were prospectively recruited. The HeartNavigator software (Philips Healthcare, Best, the Netherlands) was used to landmark the left ventricular epicardium for TA (planned puncture site [PPS]). The PPS landmark was compared with the position of the TA closure device on post-procedure CTA (actual puncture site). The distance between the PPS and actual puncture site was calculated from 2 fixed reference points (left main ostium and mitral prosthesis center) in 3 planes (x, y, and z). The distance from the left anterior descending artery at the same z-plane was also assessed. TA-related complications associated with fusion imaging were recorded. RESULTS: The median (interquartile range [IQR]) TA distance difference between the PPS and actual puncture site from the referenced left main ostium and mitral prosthesis center was 5.00 mm (IQR: 1.98, 12.64) and 3.27 mm (IQR: 1.88, 11.24) in the x-plane, 4.48 mm (IQR: 1.98, 13.08) and 4.00 mm (IQR: 1.62, 11.86) in the y-plane, and 5.57 mm (IQR: 3.89, 13.62) and 4.96 mm (IQR: 1.92, 11.76) in the z-plane. The mean TA distance to the left anterior descending artery was 15.5 +/- 7.8 mm and 22.7 +/- 13.7 mm in the x- and y-planes. No TA-related complications were identified, including evidence of coronary artery laceration. CONCLUSIONS: With the use of CTA-fluoroscopy fusion imaging to guide TA, the actual puncture site can be approximated near the PPS. Moreover, fusion imaging can help maintain an adequate access distance from the left anterior descending artery, thereby, potentially reducing TA-related complications.