Evaluation of Myocardial Stiffness in Cardiac Amyloidosis Using Acoustic Radiation Force Impulse and Natural Shear Wave Imaging.

Objective: Increased myocardial stiffness (MS) is an important hallmark of cardiac amyloidosis (CA) caused by myocardial amyloid deposition. Standard echocardiography metrics assess MS indirectly via downstream effects of cardiac stiffening. The ultrasound elastography methods acoustic radiation force impulse (ARFI) and natural shear wave (NSW) imaging assess MS more directly.

Immersion-Induced Mitral Regurgitation: A Novel Risk Factor for Swimming-Induced Pulmonary Edema.

Immersion pulmonary edema, more commonly referred to as swimming-induced pulmonary edema (SIPE), is a well-documented condition believed to be a result of immersion physiologic condition that is characterized by a peripheral-to-central redistribution of blood volume. It disproportionally affects young, healthy athletes with no clinically overt cardiovascular or pulmonary conditions. We present four cases of healthy athletes with previously documented SIPE, who participated in Institutional Review Board-approved clinical studies that examined the pathophysiologic condition and prevention of SIPE.

Left bundle branch block without a typical contraction pattern is associated with increased risk of ventricular arrhythmias in cardiac resynchronization therapy patients.

Cardiac resynchronization therapy (CRT) reduces the risk of ventricular arrhythmias (VA) in heart failure (HF) patients with left bundle branch block (LBBB) while the effect is less clear among non-LBBB patients. This study aimed to investigate if absence of LBBB features whether by echocardiography or strict ECG criteria would identify patients at risk of developing VA in a cohort with LBBB according to conventional ECG criteria. Two hundred six CRT candidates were prospectively included from 2 centers.

Predicting the Development of Reduced Left Ventricular Ejection Fraction in Patients With Left Bundle Branch Block.

Left bundle branch block (LBBB) increases the likelihood of developing reduced left ventricular (LV) ejection fraction (EF) but predicting which patients with LBBB and normal LVEF will develop decreased LVEF remains challenging. Fifty patients with LBBB and normal LVEF were retrospectively identified. Clinical, electrocardiographic, and echocardiographic variables were compared between patients who developed a decreased LVEF and those who did not.

Contractile Fronts In The Interventricular Septum: A Case For High Frame Rate Echocardiographic Imaging.

The real time high frame rate (HFR) 2-dimensional ultrasound system, T5, at Duke University is capable of imaging at up to 1000 images per second for adult cardiac imaging. A method for detecting and visualizing the mechanical contraction fronts using HFR echocardioagraphy-derived Strain Rate Image (SRI) was described in 26 patients. The Tissue Shortening Onset front durations for echocardiographic normal patients were significantly shorter than conduction disorder patients with left bundle branch block (LBBB) with intrinsic conduction and conduction disorder patients without LBBB (non-LBBB) with simulated LBBB (sLBBB).

Early cardiac dysfunction in children and young adults with perinatally acquired HIV.

Objective: To define the prevalence of early cardiac dysfunction in children and young adults with perinatally acquired HIV and predictors of cardiac function.

Design: Cross-sectional design.

Methods: Early cardiac dysfunction was defined as left ventricular (LV) global longitudinal strain z-score less than -2 or myocardial performance index at least 0.

Index of contractile asymmetry improves patient selection for CRT: a proof-of-concept study.

Background: Nearly one-third of heart failure (HF) patients do not respond to cardiac resynchronization therapy (CRT) despite having left bundle branch block (LBBB). The aim of the study was to investigate a novel method of quantifying left ventricular (LV) contractile asymmetry in HF.

Methods: Patients with HF and LBBB undergoing CRT (n = 89, 37.

Non-invasively quantified changes in left ventricular activation predict outcomes in patients undergoing cardiac resynchronization therapy.

Background: Changes in left ventricular (LV) activation after cardiac resynchronization therapy (CRT) influence survival but are difficult to quantify noninvasively.

Methods And Results: We studied 527 CRT patients to assess whether noninvasive quantification of changes in LV activation, defined by change (Δ) in QRS area (QRSA), can predict outcomes after CRT. The study outcome was time until LV assist device(LVAD), cardiac transplant, or death.

PR Prolongation predicts inadequate resynchronization with biventricular pacing in left bundle branch block.

Background: PR interval prolongation is associated with poor outcome after cardiac resynchronization therapy (CRT) among patients with left bundle branch block (LBBB) but the mechanisms are unknown. We investigated clinical outcomes, electrocardiogram (ECG), and echocardiogram changes after CRT by PR interval.

Methods: This is a retrospective study of CRT recipients with a baseline ejection fraction ≤35% and ECG showing sinus rhythm and LBBB.

Echocardiographic Assessment of Right Ventricular Function and Response to Therapy in Pulmonary Arterial Hypertension.

Echocardiography is a key tool in the management of patients with pulmonary arterial hypertension (PAH), but many potential parameters could be used to assess response to therapy. In this retrospective study of 48 patients with severe PAH at baseline, we examined echocardiographic variables before and after initiation of PAH-specific therapy to evaluate which measures of right ventricular (RV) function best correlated with clinical response to therapy as assessed by 6-minute walk distance (6MWD) and 3-year all-cause mortality. Tricuspid annular plane systolic excursion (TAPSE), mid-RV and basal-RV diameters, RV systolic pressure, and RV global longitudinal strain were all found to significantly improve after initiation of a PAH therapy.

The Association of a classical left bundle Branch Block Contraction Pattern by vendor-independent strain echocardiography and outcome after cardiac resynchronization therapy.

Background: The association of a Classical left bundle branch block (LBBB) contraction pattern and better outcome after cardiac resynchronization therapy (CRT) has only been studied using vendor-specific software for echocardiographic speckle-tracked longitudinal strain analysis. The purpose of this study was to assess whether a Classical LBBB contraction pattern on longitudinal strain analysis using vendor-independent software is associated with clinical outcome in CRT recipients with LBBB.

Methods: This was a retrospective cohort study including CRT recipients with LBBB, heart failure, and left ventricular (LV) ejection fraction ≤35%.

Non-invasive Measurement of Dynamic Myocardial Stiffness Using Acoustic Radiation Force Impulse Imaging.

Myocardial stiffness exhibits cyclic variations over the course of the cardiac cycle. These trends are closely tied to the electromechanical and hemodynamic changes in the heart. Characterization of dynamic myocardialstiffness can provide insights into the functional state of the myocardium, as well as allow for differentiation between the underlying physiologic mechanisms that lead to congestive heart failure.

Quantitative Parameters of High-Frame-Rate Strain in Patients with Echocardiographically Normal Function.

Recently, we developed a high-frame-rate echocardiographic imaging system capable of acquiring images at rates up to 2500 per second. High imaging rates were used to quantify longitudinal strain parameters in patients with echocardiographically normal function. These data can serve as a baseline for comparing strain parameters in disease states.

Predictors and Changes in Cardiac Hemodynamics and Geometry With Transcatheter Aortic Valve Implantation.

The introduction of transcatheter aortic valve implantation (TAVI) has revolutionized the treatment of patients with severe aortic stenosis (AS). However, despite the great clinical success of TAVI, less is known about the cardiac hemodynamics and structural changes to post-TAVI. We analyzed patients with AS who had a transthoracic echocardiography at most 6 months before index TAVI and follow-up transthoracic echocardiography 9 to 18 months later, performed at Duke University Medical Center from 2012 to 2014.

The mechanical and hemodynamic effects of left ventricular pacing in heart failure with preserved ejection fraction and left bundle branch block.

Cardiac resynchronization therapy (CRT) has revolutionized the care of patients with heart failure with reduced ejection fraction (HFrEF) and left bundle branch block (LBBB); some hypothesize that electrical resynchronization may also benefit patients with heart failure with preserved ejection fraction (HFpEF) and LBBB. We assessed the acute hemodynamic and mechanical impact of temporary LV pacing in 2 patients with HFpEF and LBBB and a "classic" pattern of echocardiographic dyssynchrony. LV pacing facilitated electrical resynchronization with acute resolution of mechanical dyssynchrony and improvements in invasively and non-invasively measured global cardiac function, due in part to shortening of the isovolumetric contraction period.

Vectorcardiographic QRS area is associated with long-term outcome after cardiac resynchronization therapy.

Background: Recent studies have suggested that vectorcardiographic measures predict left ventricular (LV) reverse remodeling and clinical outcome in patients receiving cardiac resynchronization therapy (CRT).

Objectives: The objectives of this study were to compare predictive abilities of different vectorcardiographic measures (QRS area and sum absolute QRS-T integral) and transformation methods (Kors and inverse Dower) and to assess the independent association between the best predictor and outcomes in CRT recipients.

Methods: This retrospective study included CRT recipients with a digital baseline electrocardiogram, QRS duration ≥120 ms, and ejection fraction ≤35%.

Crowdsourcing consensus: proposal of a novel method for assessing accuracy in echocardiography interpretation.

Quality in stress echocardiography interpretation is often gauged against coronary angiography (CA) data but anatomic obstructive coronary disease on CA is an imperfect gold standard for a stress induced wall motion abnormality. We examined the utility of crowd-sourcing a "majority-vote" consensus as an alternative 'gold standard' against which to evaluate the accuracy of an individual echocardiographer's interpretation of stress echocardiography studies. Participants independently interpreted baseline and post-exercise stress echocardiographic images of cases that had undergone follow up CA within 3 months of the stress echo in two surveys, 2 years apart.

Clinical and Echocardiographic Predictors of Outcomes in Patients With Pulmonary Hypertension.

In pulmonary hypertension (PH), measurement of various echocardiographic parameters that assess right heart function is recommended by current clinical guidelines. Limited data exists on the combined value of clinical and echocardiographic parameters in precapillary PH in the modern era of therapy. We examined the association of clinical and echocardiographic parameters with surrogate outcomes (6-minute walk distance) and hard outcomes (hospitalization or death) in patients with precapillary PH.

Long-term outcomes of mitral regurgitation by type and severity.

Background: We aimed to determine the association of MR severity and type with all-cause death in a large, real-world, clinical setting.

Methods: We reviewed full echocardiography studies at Duke Echocardiography Laboratory (01/01/1995-12/31/2010), classifying MR based on valve morphology, presence of coronary artery disease, and left ventricular size and function. Survival was compared among patients stratified by MR type and baseline severity.