The Role of Echocardiography and Other Imaging Modalities in Patients With Left Ventricular Assist Devices

Recent advances in the field of left ventricular device support have led to an increased use of left ventricular assist devices (LVADs) in patients with end stage heart disease. The primary imaging modality to monitor patients with LVADs has been echocardiography. The purpose of this review is to highlight the clinical role of echo and other noninvasive imaging modalities in the assessment of cardiac structure and function in patients with pulsatile and continuous flow LVADs. In addition, we discuss the role of imaging with emphasis on echo to detect LVAD dysfunction and device related complications

Comparative Efficacy of Nebivolol and Metoprolol to Prevent Tachycardia-Induced Cardiomyopathy in a Porcine Model

Chronic tachycardia is a well-known cause of nonischemic cardiomyopathy. We hypothesized that nebivolol, a β-blocker with nitric oxide activity, would be superior to a pure β-blocker in preventing tachycardia-induced cardiomyopathy in a porcine model. Fifteen healthy Yucatan pigs were randomly assigned to receive nebivolol, metoprolol, or placebo once a day. All pigs underwent dual-chamber pacemaker implantation. The medication was started the day after the pacemaker implantation. On day 7 after implantation, each pacemaker was set at atrioventricular pace (rate, 170 beats/min), and the pigs were observed for another 7 weeks. Transthoracic echocardiograms, serum catecholamine levels, and blood chemistry data were obtained at baseline and at the end of the study. At the end of week 8, the pigs were euthanized, and complete histopathologic studies were performed. All the pigs developed left ventricular cardiomyopathy but remained hemodynamically stable and survived to the end of the study. The mean left ventricular ejection fraction decreased from baseline by 34%, 20%, and 20% in the nebivolol, metoprolol, and placebo groups, respectively. These changes did not differ significantly among the 3 groups (P =0.51). Histopathologic analysis revealed mild left ventricular perivascular fibrosis with cardiomyocyte hypertrophy in 14 of the 15 pigs. Both nebivolol and metoprolol failed to prevent cardiomyopathy in our animal model of persistent tachycardia and a high catecholamine state

Contrast Echocardiography for Right-Sided Heart Conditions: Case Reports and Literature Review

Contrast echocardiography is recognized to be a safe, effective technique for evaluating the endocardial border and left ventricular function in patients who have suboptimal noncontrast echocardiograms. However, its use in diagnosing right-heart conditions is less well established. Herein, we report our experience with the use of contrast echocardiography for diagnosing 3 distinct right-sided heart conditions (hypokinesis of the right ventricular free wall, severe tricuspid regurgitation, and cardiac tamponade) in patients who had suboptimal echocardiograms. Further studies should be done to validate the use of contrast echocardiography for diagnosing right-heart conditions

Contrast echocardiography for right-sided heart conditions: Case reports and literature review

Contrast echocardiography is recognized to be a safe, effective technique for evaluating the endocardial border and left ventricular function in patients who have suboptimal non-contrast echocardiograms. However, its use in diagnosing right-heart conditions is less well established. Herein, we report our experience with the use of contrast echocardiography for diagnosing 3 distinct right-sided heart conditions (hypokinesis of the right ventricular free wall, severe tricuspid regurgitation, and cardiac tamponade) in patients who had suboptimal echocardiograms. Further studies should be done to validate the use of contrast echocardiography for diagnosing right-heart conditions