John Merlino

Emory University | EU · Division of Cardiology

Background: An increasing number of patients with prior coronary artery bypass grafting (CABG) now present with severe aortic stenosis. The proposed benefit of surgical (SAVR) vs transcatheter aortic valve replacement (TAVR) is unknown. The objective of this study was to compare short-term and midterm outcomes of patients undergoing isolated SAVR...

Transcatheter aortic valve replacement (TAVR) is an effective treatment in patients with severe aortic stenosis unsuitable for surgical aortic valve replacement (SAVR). This study evaluated the early experience with the posttrial application of TAVR, with specific focus on non-transfemoral (TF) access. All patients who underwent posttrial TAVR at E...

Background: The newly developed 2-dimensional speckle tracking imaging (2D-STI) allows assessment of left ventricular (LV) rotation and twist. The aims of the present study are to establish normal values and to examine the effect of aging and gender on these parameters. Methods: We studied 228 healthy subjects (109 males, mean age 44 ± 15 years,...

Background: Although two-dimensional speckle tracking (2DST) has been validated in animal and early clinical studies for quantitative evaluation of myocardial motion and contractility, there are only limited measurements in large healthy population to be used as reference data, which severely restricts its clinical application. This study aimed at...

Atrioventricular (AV) delay in cardiac resynchronisation therapy (CRT) recipients are typically optimised at rest. However, there are limited data on the impact of exercise-induced changes in heart rate on the optimal AV delay and left ventricular function. The authors serially programmed AV delays in 41 CRT patients with intrinsic sinus rhythm at...

Numerous criteria believed to define a positive response to cardiac resynchronization therapy have been used in the literature. No study has investigated agreement among these response criteria. We hypothesized that the agreement among the various response criteria would be poor. A literature search was conducted with the keywords "cardiac resynchr...

Doppler tissue imaging (DTI)-based dyssynchrony parameters failed to predict response to cardiac resynchronization therapy (CRT) in the multicenter Predictors of Response to Cardiac Resynchronization Therapy (PROSPECT) trial. Large variability during the interpretation of DTI data was one of several factors thought to contribute to this failure. In...

Hypertension is the most common cause of left ventricular (LV) hypertrophy. However, multiple causes can lead to LV hypertrophy, each of which has different histological and mechanical properties. To assess the value of a novel speckle-tracking echocardiographic measurement of myocardial strain and strain rate in defining the mechanical properties...

Data from single-center studies suggest that echocardiographic parameters of mechanical dyssynchrony may improve patient selection for cardiac resynchronization therapy (CRT). In a prospective, multicenter setting, the Predictors of Response to CRT (PROSPECT) study tested the performance of these parameters to predict CRT response. Methods and Res...

Hypertensive Heart DiseaseAssessment of Hypertensive Heart Disease by Two-Dimensional and Conventional Spectral DopplerTissue Doppler Echocardiographic Findings in Hypertensive Heart DiseaseClinical Utility of Tissue Doppler EchocardiographyReferences

Left ventricular dyssynchrony is often diagnosed by comparing velocity curves from Doppler tissue images of two or more myocardial regions. Velocity curves are generated by placing sample volumes or regions of interest (ROIs) within the myocardium. ROIs need to be manually relocated to maintain a midmyocardial location as the heart moves, but are f...

The initial clinical presentation and echocardiography have key roles in risk stratification of patients with acute pulmonary embolism (PE). To assess the value of shock index and echocardiographic abnormalities as predictors of in-hospital complications and mortality, echocardiographic features of 159 patients diagnosed with acute PE were reviewed...

Quantification of left ventricular dyssynchrony using Doppler tissue imaging may improve selection of patients who will benefit from cardiac resynchronization therapy. Most methods used to quantify dyssynchrony use a time-to-peak analysis, which is quantitatively simplistic and requires manual identification of systole and selection of peak velocit...

Risk stratification of patients with a diagnosis of acute pulmonary embolism (PE) is crucial in deciding appropriate management. An electrocardiographic (ECG) scoring system may potentially be useful in identifying patients at high risk of increased hospital morbidity and mortality from acute PE. Electrocardiography and echocardiography of 159 pati...

Multiple echocardiographic criteria have been proposed to diagnose mechanical dyssynchrony in patients with heart failure without being validated against a model of cardiac dyssynchrony with heart failure. This study examines which of these methods can detect dyssynchrony in a canine model. Adult mongrel dogs underwent His-bundle ablation and right...

PurposeTo compare longitudinal myocardial velocity and time to peak longitudinal velocity obtained with magnetic resonance phase velocity mapping (MR-PVM) and tissue Doppler imaging (TDI), and to assess the reproducibility of each method.Materials and Methods Longitudinal myocardial velocity was measured by TDI and MR-PVM in 10 normal volunteers an...

Background: Cardiac resynchronization therapy (CRT) is currently indicated in patients with moderate to severe heart failure, a wide QRS complex and significant left ventricular dysfunction despite optimal medical therapy. Adoption of these criteria for CRT results in a favorable response in only two thirds of candidates. Methods: "Predictors of...

Neurologic complications remain a significant cause of morbidity and mortality in cardiac surgery. Risk factors for neurologic injuries include the presence of atheromatous disease in the aorta. Epiaortic ultrasound has been shown to be superior in detecting the extent and location of atheromatous disease. The SonoSite Corporation (Bothell, WA) has...

Cardiac resynchronization therapy (CRT) improves symptoms and functional status in heart failure patients; however, current selection criteria need improvement. A novel tissue Doppler imaging parameter, the peak velocity difference (PVD), defined as the greatest difference in time to peak velocity between any of 6 left ventricular regions, may bett...