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Peter Alagona, MD[⁎][1] Gerard Aurigemma, MD[‡][2] Javed Butler, MD, MPH[§][3] Don Casey, MD, MPH, MBA[∥][4] Ricardo Cury, MD[#][5] Scott Flamm, MD[¶][6] Tim Gardner, MD[⁎⁎][7] Rajesh Krishnamurthy, MD[††][8] Joseph Messer, MD[⁎][1] Michael W. Rich, MD[‡‡][9] Henry

Despite improvements in treatments for heart failure in the last 30 years, significant barriers exist for underserved populations including access to care, nonadherence to prescribed treatments, and lack of support for self-management. Community health workers (CHW) are specially trained lay-people

An exceptional view of the heart through quality ultrasound imaging of the cardiovascular system was the theme of the 18th Annual Scientific Sessions of the American Society of Echocardiography, which took place in Seattle, Washington, from June 16 to 20, 2007. This meeting showcased how the latest

OBJECTIVES To test the feasibility of objective and automated evaluation of echocardiographic stress tests, we studied the ability of segmental analysis of color kinesis (CK) images to detect dobutamine-induced wall motion abnormalities and compared this technique with inexperienced reviewers of conventional gray-scale images. BACKGROUND Conventional interpretation of stress echocardiographic studies is subjective and experience dependent. METHODS CK images were obtained in 89 of 104 consecutive patients undergoing clinical dobutamine stress studies and were analyzed using custom software to calculate regional fractional area change in 22 segments in four standard views. Each patient’s data obtained at rest was used as a control for automated detection of dobutamine-induced wall motion abnormalities. Independently, studies were reviewed without CK overlays by two inexperienced readers who classified each segment’s response to dobutamine. A consensus reading of two experienced reviewers was used as the gold standard for comparisons. In a subgroup of 16 patients, these consensus readings and CK detection of wall motion abnormalities were compared with coronary angiography. RESULTS The consensus reading detected ischemic response to dobutamine in 43 of 1958 segments in 23 of 89 patients. Automated detection of stress-induced wall motion abnormalities correlated more closely with the standard technique than the inexperienced reviewers (sensitivity 0.76 vs. 0.55, specificity 0.98 vs. 0.94 and accuracy 0.97 vs. 0.92). When compared with coronary angiography in a subgroup of patients, analysis of CK images differentiated between normal and abnormal wall motion more accurately than expert readers of gray-scale images (accuracy of 0.93 vs. 0.82). CONCLUSIONS Analysis of CK images allows fast, objective and automated evaluation of regional wall motion, sensitive enough for clinical dobutamine stress data and more accurate than inexperienced readers. This method may result in a valuable adjunct to conventional visual interpretation of dobutamine stress echocardiography.

Objectives. This study was performed to determine the efficacy of new encircling overlapping multipulse, multipathway waveforms for transthoracic defibrillation. Background. Alternative waveforms for transthoracic defibrillation may improve shock success. Methods. First, we determined the shock success achieved by three different waveforms at varying energies (18–150 J) in 21 mongrel dogs after short-duration ventricular fibrillation. The waveforms tested included the traditional damped sinusoidal waveform, a single pathway biphasic waveform, and a new encircling overlapping multipulse waveform delivered from six electrode pads oriented circumferentially. Second, in 11 swine we compared the efficacy of encircling overlapping multipulse shocks given from six electrode pads and three capacitors versus encircling overlapping shocks given from a device utilizing three electrodes and one capacitor. Results. In the first experiment, the encircling overlapping waveform performed significantly better than biphasic and damped sinusoidal waveforms at lower energies. The shock success rate of the overlapping waveform (six pads) ranged from 67 ± 4% (at 18–49 J energy) to 99 ± 3% at ≥150 J; at comparable energies biphasic waveform shock success ranged from 26 ± 5% (p < 0.01 vs. encircling overlapping waveforms) to 99 ± 5% (p = NS). Damped sinusoidal waveform shock success ranged from 4 ± 1% (p < 0.01 vs. encircling overlapping waveform) to 73 ± 9% (p = NS). In the second experiment the three electrode pads, one capacitor encircling waveform achieved shock success rates comparable with the six-pad, three-capacitor waveform; at 18–49 J, success rates were 45 ± 15% versus 57 ± 12%, respectively (p = NS). At 100 J, success rates for both were 100%. Conclusions. We conclude that encircling overlapping multipulse multipathway waveforms facilitate transthoracic defibrillation at low energies. These waveforms can be generated from a device that requires only three electrodes and one capacitor.

Objectives. We tested the feasibility of using analysis of color kinesis images to objectively assess global and regional left ventricular (LV) diastolic function in patients with dilated cardiomyopathy (DCM). In addition, the ability of this technique to track drug-induced changes on LV diastolic properties was studied. Background. Diastolic dysfunction contributes to symptomatology in patients with DCM. The assessment of LV diastolic function using conventional Doppler echocardiography is indirect and is confounded by multiple variables. Moreover, the noninvasive evaluation of regional diastolic properties is difficult. In contrast, color kinesis directly tracks and color-encodes regional diastolic endocardial motion. Methods. We studied 24 patients with DCM and mitral regurgitation (MR) and 24 age-matched normal subjects. Transmitral and pulmonary vein flow velocities were measured using pulsed Doppler echocardiography. Diastolic color kinesis images were used to calculate indexes of magnitude and timing of global and regional diastolic function. Diastolic asynchrony was evaluated in different subgroups of patients with DCM. The effects of drug infusions (nitroprusside and dobutamine) were also studied. Results. Color kinesis indexes of global diastolic function showed significant differences between patients with DCM and normal subjects. Compared with Doppler indexes, color kinesis was less confounded by MR and was capable of differentiating between drug-induced lusitropic and vasodilator effects. Diastolic asynchrony was increased in patients with DCM and severe MR. Conclusions. Quantitative analysis of global and regional LV diastolic function in patients with DCM using color kinesis is feasible.

Objectives. This study sought to determine the effect on transthoracic Impedance of placement of defibrillation electrodes on the female breast versus adjacent to or under the breast. Background. Transthoracic impedance is a major determinant of transthoracic current flow in defibrillation. For a given energy setting, a high transthoracic impedance reduces current flow and may adversely affect the ability of electric shocks to accomplish defibrillation. We hypothesized that the increased interelectrode tissue associated with placement of the apex defibrillation electrode on the female breast would result in increased transthoracic impedance compared with electrode placement lateral to or under the breast. Method. Transthoracic impedance was measured noninvasively by passing a 5-V, 31.25 kHz square wave current through the chest and comparing the low level current flow to known references. We measured transthoracic impedance associated with three different apex defibrillation electrode positions—on the breast, under the breast and lateral to the breast—in 25 women (brassiere size 34A to 48C 65 to 75 years old, body weight 128 to 328 lb [58 to 148 kg] and 2 mm. The measurements were taken with a modified defibrillator that accurately predicts transthoracic impedance without delivering an actual shock. The measurement sequence was random. Results. The average measured transthoracic impedance with placement of the apex defibrillation electrode on the breast was 95 ± 25 ohms (mean ± SD), under the breast 84 ± 17*ohms and lateral to the breast 83 ± 20*ohms (asteriskindicates p < 0.01 vs. on the breast by analysis of variance). The study cohort was also classified into two groups: large breasted (brassiere size ≥ 40) and small breasted (brassiere size ≤39). The measured transthoracic impedances for the large-breasted group were 112 ± 20 ohms for on the breast, 94 ± 13*ohms for under the breast and 98 ± 19*ohms for lateral to the breast. For the small breasted group, the similar transthoracic impedance measurements were 81 ± 21, 77 ± 16 and 71 ± 13*ohms, respectively. Conclusions. In women, placement of the apex defibrillation electrode on the breasts results in higher transthoracic impedance, which will reduce current flow. We recommend placing the apex electrode lateral to or underneath the breast.

Both tricuspid annular peak systolic excursion (TAPSE) and tricuspid lateral annular systolic velocity (S') are recommended for the evaluation of right ventricular (RV) systolic performance, despite being confounded by tricuspid regurgitation (TR). The usefulness of RV free wall longitudinal strain

OBJECTIVES The purpose of this study was to compare the results of physical examinations (PEs) performed by board-certified cardiologists with the results of point-of-care (POC) echocardiography in a group of patients with cardiovascular disease. BACKGROUND Although cardiovascular PE is crucial in the evaluation of patients with suspected heart disease, the skills required to diagnose abnormal cardiovascular findings have been declining. Echocardiography is a powerful noninvasive cardiovascular diagnostic tool; however, echocardiographic evaluation of patients is not performed at the time of patient encounter (POC echocardiography), beacuse current platforms are cumbersome and expensive for individual physician use. The development of miniaturized echocardiographic equipment has the potential to overcome some of these limitations. METHODS Thirty-six subjects had a complete cardiovascular examination by four board-certified cardiologists. The physicians subsequently imaged each patient using a miniaturized echocardiographic platform. The yield of PE and POC echocardiography were compared using a complete echocardiographic study as the gold standard, performed on an upper-end platform. RESULTS Cardiac examination failed to detect 59% of the overall cardiovascular findings. Physician-performed echocardiography with the prototype device missed 29% of the overall cardiovascular pathology. When considering only the major cardiovascular findings, the cardiologists' PEs still failed to correctly detect 43%. Point-of-care echocardiography reduced this to 21% without significant interphysician variation. CONCLUSIONS Point-of-care echocardiography using a miniaturized echocardiographic platform substantially improved the detection of important cardiovascular pathology compared with PE. Use of this device by a cardiovascular specialist with training in echocardiography as a routine adjunct to PE appears to be useful.

Cardiovascular magnetic resonance (CMR) late gadolinium enhancement (LGE) imaging is used to detect cardiac amyloid (CA); however, image interpretation is very challenging due to poor image quality. Normally, the inversion time (TI) at which the blood pool nulls is shorter than that of the

Although three-dimensional (3D) echocardiography has been used to measure mitral valve areas (MVA) in mitral stanosis from both transescphageal (TEE) and transthoracic (TTE) approaches, the accuracy of these techniques has not been compared. Accordingly, we compared the accuracy of mitral valve area measurements obtained with a 3D volumetric free-hand (FH) TEE approach to those acquired with a 3D TEE approach using invasive Gorlin mitral valve area as the "gold standard". Methods: 19 patients (49±18 yrs) with mitral stenosis were studied with TEE and free-hand TEE prior to valvuIoplasfy. During TEE, 2D images were acquired every 3 ° over 180 ° (SONOS 5500). Freehand images were obtained in 80 planes gated to respiration and heart rate using magnetic tracking, and processed on Omniview (TomTec). Direct 3D mitral valve area measurements reconstructed from TEE and free-hand TEE were compared to invasive Gorlin mitral valve area. Results: Both 3D techniques, free*hand TEE and TEE, were in good agreement with invasive data (Bland-AItmann and correlation, figure). Conclusions. Mitral valve orifice area measurements obtained with free-hand TEE scanning are as accurate as those obtained with 3D TEE, with the advantages of being noninvasive and suitable for serial measurements.

Objectives. We sought to demonstrate that direct current (DC) shocks to the heart generate free radicals.Background. Although it is a lifesaving maneuver, defibrillation is known to have myocardial toxicity. The mechanism of this toxicity is unknown. If DC shocks generate free radicals, free radicals could be a mechanism of myocardial injury.Methods. In a canine model, DC shocks of 10 to 100 J were delivered to the epicardium of both beating and fibrillating hearts, and 200-J transthoracic shocks were administered in dogs with beating hearts. Ascorbate free radical (AFR) concentration was measured in arterial blood and blood continuously withdrawn from the coronary sinus. In some dogs, the antioxidant enzymes superoxide dismutase (15,000 U/Kg) and catalase (55,000 U/kg) (SOD/Cat) were administered before shocks.Results. Ascorbate free radicals were generated by DC shocks. A peak AFR increase of 14 ± 2% (mean ± SEM) was seen 5 to 6 min after 100-J epicardial shocks. A peak AFR increase of 7 ± 5% occurred after transthoracic shocks. There was a significant linear relation between the shock energy and peak percent AFR increase: %AFR increase = 0.18 (Shock energy) + 2.9 (r = 0.73, p < 0.0001). Shocks delivered to hearts in ventricular fibrillation (30s) resulted in generation of AFR equal to but not greater than that observed during similar shocks delivered to beating hearts in sinus rhythm. Multiple successive shocks (100 J delivered twice or five times) did not result in a greater AFR increase than single 100-J shocks, indicating that peak, not cumulative, energy is the principal determinant of AFR increase. Animals receiving SOD/Cat before shock administration, showed significant attenuation of the AFR increase.Conclusions. Direct current epicardial and transthoracic shocks generate free radicals; antioxidant enzymes reduce the free radical generation by shocks.

Objectives We investigated the usefulness of echocardiographic contrast perfusion imaging in differentiating cardiac masses. Background Two-dimensional echocardiography is the primary diagnostic modality for cardiac masses. However, differentiation between the different types of cardiac masses may be difficult at times. We hypothesized that echocardiographic contrast perfusion imaging would differentiate the neo-vascularization of malignancies from the avascularity of thrombi and the sparse vascularity of stromal tumors. Methods Sixteen patients with cardiac masses underwent power-modulation imaging after echocardiographic intravenous contrast administration. Pixel intensities in the mass and an adjacent section of myocardium were analyzed visually and by dedicated software. All masses had a pathologic diagnosis or resolved after anticoagulation. In a subset of patients, video-intensity curves of contrast replenishment in the mass and myocardium over time were generated. The post-impulse steady-state pixel intensity (A) and initial rate of contrast replenishment after impulse (β) were compared with an index of blood vessel area on pathology. Results In seven of 16 patients, contrast enhancement resulted in greater pixel intensity in the mass than in the adjacent myocardium. All of these masses were classified pathologically as malignant (n = 6) or benign and vascular (n = 1). Nine masses demonstrated decreased pixel intensity, compared with the myocardium, and were diagnosed pathologically as myxomas (n = 2) or thrombi (n = 5), or they resolved with anticoagulation (n = 2). For the subset of patients, β correlated with the vessel area index (r = 0.60). Conclusions Echocardiographic contrast perfusion imaging aids in the differentiation of cardiac masses. Compared with the adjacent myocardium, malignant and vascular tumors hyper-enhanced, whereas stromal tumors and thrombi hypo-enhanced.

Previous work in our lab has shown that direct current (DC) shocks generate free radicals, which may be toxic to the myocardium. We hypothesized that administration of free radical scavenging enzymes prior to shock delivery would attenuate the generation of free radicals. We used a newly developed and validated technique for real time quantitation of free radical production: ascorbyl free radical (AFR) concentration in coronary sinus blood, measured by electron paramagnetic resonance. In 10 open-chest dogs, 75J and 100J epicardial shocks were administered during NSR. Then superoxide dismutase (SOD, 15,000 μ/kg).and catalase (CAT. 55,000 u/kg) were given as a continuous infusion. Ten mins. after initiating the SOD/CAT infusion, 75J and 100J shocks were repeated. Four control dogs received normal saline instead of SOD/CAT. Results % Δ AFR Area AFR Energy Pre SOD Post SOD Pre SOD Post SOD 75 J 17 ± 4 5 ± 2 * 150 ± 39 37 ± 8 * 100 J 20 ± 5 6 ± 2 * 184 ± 26 53 ± 17 * x ± SO. * p l 0,05 post vs. pre. Area = integrated area under AFR concentration vs. time curve The 4 control dogs showed no significant differences in AFR generation when comparing shocks administered before and after saline infusion rather than SOD/CAT. Conclusion antioxidant enzymes markedly attenuate free radical generation by DC shocks. If free radicals are a mechanism of defibrillation injury in patients, drugs with free radical inhibiting or scavenging properties may prevent such injury.