Clinical Trial Principles and Endpoint Definitions for Paravalvular Leaks in Surgical Prosthesis.

The VARC (Valve Academic Research Consortium) for transcatheter aortic valve replacement set the standard for selecting appropriate clinical endpoints reflecting safety and effectiveness of transcatheter devices, and defining single and composite clinical endpoints for clinical trials. No such standardization exists for circumferentially sutured surgical valve paravalvular leak (PVL) closure. This document seeks to provide core principles, appropriate clinical endpoints, and endpoint definitions to be used in clinical trials of PVL closure devices. The PVL Academic Research Consortium met to review evidence and make recommendations for assessment of disease severity, data collection, and updated endpoint definitions. A 5-class grading scheme to evaluate PVL was developed in concordance with VARC recommendations. Unresolved issues in the field are outlined. The current PVL Academic Research Consortium provides recommendations for assessment of disease severity, data collection, and endpoint definitions. Future research in the field is warranted.

A standardized protocol to reliably visualize the left atrial appendage with intracardiac echocardiography: Importance of multiple imaging sites.

BACKGROUND: Currently, there is no accepted protocol for left atrial appendage (LAA) imaging with intracardiac echocardiography (ICE). OBJECTIVE: This study aimed to assess the utility of ICE to reliably visualize the entire cavity of the LAA and propose a specific procedural protocol to achieve the above objective. METHODS: We created a three-dimensional reconstruction of the LAA, using two-dimensional ICE sections obtained from three different location (the right atrium [RA], right ventricle inflow [RVI], and right ventricular outflow [RVOT]). We then compared the three-dimensional LAA reconstruction by ICE with one obtained by cardiac computed tomography angiography (CCTA) for morphological and volume differences. RESULTS: Three-dimensional reconstruction with ICE could reliably reproduce the LAA as visualized with CCTA but only when ICE sampling was performed from at least two catheter positions. There was no statistically significant difference between LAA volumes obtained with ICE and CCTA (P = 0.33). The contribution of each anatomical location to the total volume was 17% ± 16.6%, 74% ± 13.3%, and 33% ± 26% for RA, RVI, and RVOT, respectively. CONCLUSION: In comparison with CCTA, the LAA can be reliably visualized in its entity by ICE, but only if multiple imaging positions (RA, RV inflow, and RVOT) are used.

The role of percutaneous vacuum-assisted thrombectomy for intracardiac and intravascular pathology.

Vacuum-assisted thrombectomy (VAT) is a mechanical suction device that can be deployed to aspirate thrombi in the heart and vascular system. Successful percutaneous aspiration of iliocaval, right heart, and pulmonary arterial thrombi have been reported, in addition to the debulking of intravascular and intracardiac masses and vegetations. VAT is indicated for patients who are poor surgical candidates and/or have a contraindication to thrombolysis. This review discusses the mechanism, current results, potential clinical indications, and limitations of VAT for iliocaval and intracardiac mass removal.

Intracardiac Echocardiography for Structural Heart and Electrophysiological Interventions.

PURPOSE OF REVIEW: With an increasing number of interventional procedures performed for structural heart disease and cardiac arrhythmias each year, echocardiographic guidance is necessary for safe and efficient results. The purpose of this review article is to overview the principles of intracardiac echocardiography (ICE) and describes the peri-interventional role of ICE in a variety of structural heart disease and electrophysiological interventions. RECENT FINDINGS: Both transthoracic (TTE) and transesophageal echocardiography have limitations. ICE provides the advantage of imaging from within the heart, providing shorter image distances and higher resolution. ICE may be performed without sedation and avoids esophageal intubation as with transesophageal echocardiography (TEE). Limitations of ICE include the need for additional venous access with possibility of vascular complications, potentially higher costs, and a learning curve for new operators. Data supports the use of ICE in guiding device closure of interatrial shunts, transseptal puncture, and electrophysiologic procedures. This paper reviews the more recent reports that ICE may be used for primary guidance or as a supplement to TEE in patients undergoing left atrial appendage (LAA) closure, interatrial shunt closure, transaortic valve implantation (TAVI), percutaneous mitral valve repair (PMVR), paravalvular leak (PVL) closure, aortic interventions, transcatheter pulmonary valve replacement (tPVR), ventricular septal defect (VSD), and patent ductus arteriosus (PDA) closure. ICE imaging technology will continue to expand and help improve structural heart and electrophysiology interventions.

Footprints of cardiac mechanical activity as expressed in lung Doppler signals.

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.

Guidance of post myocardial infarction ventricular septal defect and pseudoaneurysm closure.

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.

Review of surgical prosthetic paravalvular leaks: diagnosis and catheter-based closure.

Paravalvular leak (PVL) is an uncommon yet serious complication associated with surgical prosthetic valve implantation. Paravalvular leak can have significant clinical consequence such as congestive heart failure, haemolytic anaemia, and infective endocarditis. Recently, transcatheter therapy has been applied to the treatment of this disorder with reasonable procedural and clinical success. This review discusses the current state of PVLs, the utilization of multi-modality imaging in their diagnosis and treatment, and the available therapeutic options. Further aim of this review is to examine transcatheter therapy of PVLs including the principles, outcomes, and procedural-related complications.

Interventional echocardiography in structural heart disease.

Over the past decade, catheter based treatments of an increasing variety of cardiac diseases have expanded dramatically. These advancements became available through new developments and improvements in available devices, as well as increasing expertise of operators. However, arguably it is the innovation and progress in imaging techniques, and in particular in echocardiography, that allowed for such a surge in available percutaneous procedures. In this paper, current echocardiographic techniques, imaging protocols and recommendations will be reviewed and clinical examples will be shown to illustrate the use and importance of echocardiographic imaging in catheter based procedures for structural heart disease.

Vacuum thrombectomy of large right atrial thrombus.

We report a novel technique for percutaneous removal of the right heart thrombi using a suction cannula. This method allowed complete en bloc removal of the right atrial thrombus avoiding surgical procedure in a high risk patient.

Commissural mitral regurgitation detected by abnormal blood flow pattern in the left atrial appendage.

An 86-year-old man with severe symptomatic aortic stenosis underwent an aortic valve replacement. A transesophageal echocardiogram (TEE) was performed during the surgery and demonstrated mild mitral regurgitation (MR). The patient's symptoms persisted despite surgery, and subsequent TEE demonstrated prolapse of the posteromedial commissural leaflet, with evidence of a severe, very eccentric MR jet which was directed laterally and superiorly. The jet was almost missed in most imaging planes and could finally be exposed by withdrawing the probe to the level of the aortic valve and left atrial appendage.

Three-dimensional echocardiography in the electrophysiology laboratory.

The use of three-dimensional echocardiography (3DE) during electrophysiology (EP) procedures is the end product of years of growth in two diverse cardiology subspecialties; namely, advanced cardiac imaging and the EP. During the past decade, progress in both fields has resulted in many important advances that have culminated in their union for a new area of growth and development. Imaging advances have provided the cardiovascular specialist with enhanced cardiac volume and function data, and more recently, 3DE capabilities with improved spatial and temporal resolution providing unprecedented spatial relationships. This latter development is valued by EP specialists in need of hitherto never required anatomic knowledge as they press forward with extraordinary expansion in their capabilities. It makes sense that by combining these two rapidly growing subspecialties, future capabilities in patient care may be achieved that would otherwise not be possible. This paper discusses the value of 3DE during EP procedures and offers the readers insight into this novel multispecialty hybrid arena. Using this model as a template, it is likely that the readers may identify other areas within their practices where periprocedural advanced imaging may afford significant dividends in patient outcomes.

Aortic atherosclerosis and embolic events.

Aortic plaques are a manifestation of the general process of atherosclerosis in which there is a progressive accumulation of cholesterol and other lipids in the intimal-medial layer of the aorta with secondary inflammation, repetitive fibrous tissue deposition, and eventually luminal surface erosions and appearance of often mobile thrombi protruding into the lumen of the aorta. Aortic plaques may give rise to two types of emboli: thromboemboli and atheroemboli (cholesterol crystal emboli). Thromboemboli are relatively large, tend to occlude medium to large arteries, and cause strokes, transient ischemic attacks, and renal infarcts and other forms of peripheral thromboembolism. Cholesterol crystal emboli are relatively minute, tend to occlude small arteries and arterioles, and may cause the blue toe syndrome, new or worsening renal insufficiency, gut ischemia, etc. Transesophageal echocardiography remains the gold standard for visualization of aortic plaques in the thoracic aorta. There are no proven therapies for aortic embolism per se; general atherosclerosis management strategies are recommended.

Cholesterol embolization syndrome.

PURPOSE OF REVIEW: To describe cholesterol embolization syndrome (CES) and its risk factors, pathophysiology, clinical presentation, diagnosis and treatment. RECENT FINDINGS: To date, no specific diagnostic test (other than biopsy) for CES has been developed. Effective treatments for CES are yet to be developed. SUMMARY: CES (also referred to as cholesterol crystal embolization, atheromatous embolization or atheroembolism) occurs when cholesterol crystals and other contents of an atherosclerotic plaque embolize from a large proximal artery to smaller distal arteries, causing ischemic end-organ damage. Clinical manifestations of CES include constitutional symptoms (fever, anorexia, weight loss, fatigue and myalgias), signs of systemic inflammation (anemia, thrombocytopenia leukocytosis, high erythrocyte sedimentation rate, elevated levels of C-reactive protein, hypocomplementemia), hypereosinophilia, eosinophiluria, acute onset of diffuse neurologic deficit, amaurosis fugax, acute renal failure, gut ischemia, livedo reticularis and blue-toe syndrome. CES may occur spontaneously or after an arterial procedure. There is no specific laboratory test for CES. Retinal exam demonstrating Hollenhorst plaques supports the diagnosis of CES. Biopsy of target organs (usually skin, skeletal muscles or kidneys) is the only means of confirming the diagnosis of CES. Treatment consists of supportive care and general management of atherosclerosis and arterial ischemia.

Triple left ventricular outflow tract obstruction.

A 59-year-old man had, over a period of 5 years, three different clinical scenarios which led to dynamic left ventricular outflow tract obstruction (LVOTO). Initially, this man who suffered from hypertrophic cardiomyopathy presented with asymmetric septal hypertrophy and systolic anterior motion (SAM) of the anterior mitral leaflet, along with mitral regurgitation. He was treated by septal myectomy and mitral valve repair with insertion of an artificial mitral ring. Several years later, he presented with severe LVOTO, this time related to the anteriorly displaced mitral coaptation site and the prosthetic ring. The ring and the anterior mitral leaflet were resected and a prosthetic mitral valve implanted. Several years later, the patient presented with LVOTO for a third time. It was now SAM of the remaining posterior leaflet that was responsible for the LVOTO.

Pulmonary Doppler signals: a potentially new diagnostic tool.

AIMS: To overcome the limitations due to ultrasound attenuation by the air in the lungs, in order to study the pulmonary system using an advanced signal processing technology. METHODS AND RESULTS: Pulsed spectral Doppler signals were obtained over the chest wall using a signal processing and algorithm package (transthoracic parametric Doppler, TPD, EchoSense Ltd, Haifa, Israel) in conjunction with a non-imaging Doppler device (Viasys Healthcare, Madison, WI, USA) coupled with an electrocardiogram. The signals picked up by a transducer positioned at various locations over the chest wall, were treated for noise, analysed parametrically and displayed in terms of both velocity and power originating from moving ultrasound reflectors. Clear reproducible lung Doppler signals (LDS) were recorded. Up to five bidirectional triangular waves with peak velocities of 20-40 cm/s, that survived the 40 dB/cm attenuation of the lung, were recorded during each cardiac cycle. The first signal coincides with early ventricular systole, the second with late systole, the third and fourth with diastole, and the last with atrial contraction. CONCLUSION: LDS originate from different elements and phases of cardiac activity that generate mechanical waves which propagate throughout the lung and are thus expressed in pulsatile changes in ultrasound reflections. While such signals could originate either from pulsatile blood flow or reflections from movement of the blood vessel--alveolar air interface, the experimental evidence points towards the tissue--air interface movements due to vessel expansion as the origin. The LDS can potentially be an important tool for diagnosing and characterizing cardio-pulmonary physiological states and diseases.

Normal intima-media thickness on carotid ultrasound reliably excludes an ischemic cause of cardiomyopathy.

BACKGROUND: Coronary artery disease (CAD) is the most common cause of left ventricular systolic dysfunction (LVSD). Patients with ischemia as the cause of LVSD may warrant revascularization. Angiography is the most accurate method of CAD diagnosis but is invasive, expensive, and associated with some risk. Noninvasive imaging for CAD often involves expensive equipment, radiation exposure, medication, and/or contrast administration. Carotid ultrasound with measurement of intima-media thickness (IMT) is safe and inexpensive. Carotid IMT is well correlated with the presence of CAD. We assessed the accuracy of carotid ultrasound for identification of CAD as a potential etiology of LVSD. METHODS: Patients with LVSD (ejection fraction < or =40%) of uncertain etiology referred for angiography underwent carotid ultrasound. Patients with history of myocardial infarction were excluded. Two experienced cardiologists blinded to CAD status determined common carotid artery (CCA) IMT and plaque. Significant CAD was defined as > or =50% stenosis of any major artery. Ischemic LVSD was defined as (1) left main and/or proximal left anterior descending coronary artery > or =75% or (2) > or =2 major arteries with > or =75% stenosis. RESULTS: Mean ejection fraction was 27% +/- 10% in 150 patients. Significant CAD was found in 64 (42.7%) and ischemic LVSD in 40 (26.7%). Carotid plaque was seen in 95 (63.3%). Mean CCA IMT was > or =0.9 mm in 69 (46.0%). The combination of mean CCA IMT <0.9 mm and no plaque had negative predictive value for ischemic LVSD of 98%. CONCLUSIONS: Carotid ultrasound with IMT measurement is a valuable screening tool for excluding an ischemic etiology of LVSD when CAD is suspected.

Percutaneous closure of a post-myocardial infarction ventricular septal defect guided by real-time three-dimensional echocardiography.

We present an adult patient who had an acute myocardial infarction complicated by a ventricular septal defect and had it repaired percutaneously. Real-time three-dimensional echocardiography (RT3D) before and during the closure procedure were performed. RT3D provided anatomical and functional information of the defect as well as real-time guidance during the procedure. This case highlights the utility of three-dimensional echocardiography in guiding transcatheter procedures.

Isolated left atrial appendage ostial stenosis.

A patient with atrial tachycardia presented with dyspnoea on exertion. Transoesophageal echocardiography revealed idiopathic left atrial appendage stenosis. The mouth of the atrial appendage was narrowed, and there was a high velocity to and fro jet between the left atrial body and the left atrial appendage. The study, therefore, suggested isolated left atrial appendage orifice stenosis.

Non-Doppler two dimensional strain imaging for evaluation of coronary artery disease.

Over the recent years, strain echocardiography has emerged as a quantitative technique for the evaluation of global and segmental cardiac function. Strain is a measure of deformation, expressed as a percent change in a segment's length compared to its predeformation length. Strain rate (SR) is the local rate of deformation or strain per unit time. Recently non-Doppler two dimensional strain imaging has been developed. This technique is based on tracking ultrasonic speckles from the two dimensional echocardiographic images. These speckles are followed over a number of successive frames, and myocardial velocity is calculated by measuring frame-to-frame changes. This technique is independent of the Doppler angle of incidence and allows measurement of several vectors of strain within myocardial tissue. Non-Doppler strain is a powerful tool, enabling detection of subtle abnormalities in myocardial function. Current evidence shows that non-Doppler strain imaging may allow identification of the early changes that occur with ischemic insult to the myocardium. It may also provide a tool for identification of scarred, non-viable myocardium, with similar accuracy to that of cardiac MRI. Non-Doppler strain imaging is likely to become a standard tool in the evaluation of patients with ischemic heart disease.