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Advances in the field of device support have led to increased use of continuous-flow left ventricular assist devices (LVADs) to improve outcomes in patients with end-stage heart disease. Newer-generation LVADs have become the pump of choice for bridging to heart transplantation and as destination therapy for patients with contraindications to transplantation.1 Different imaging modalities have played a major role in LVAD preoperative, early postoperative, and long-term follow-up management. The primary imaging modality to monitor patients with continuous-flow LVADs is echocardiography. The present review highlights the role of echocardiography and the other imaging modalities in the assessment of ventricular size and function, intracardiac hemodynamics, and myocardial recovery of patients with continuous-flow LVADs. The evolving role of echocardiography in facilitating the identification of optimal pump speed settings in patients supported by continuous-flow LVADs will be discussed, along with a summary of the protocol we use for image acquisition and reporting. Furthermore, we will provide a summary of echocardiographic findings associated with continuous-flow LVAD-related complications and device dysfunction. Second-generation continuous-flow LVAD rotary pumps offer several advantages over pulsatile first-generation pumps, including smaller size and, importantly, greater long-term mechanical reliability. The different types of continuous-flow LVADs and device characteristics, including pump speeds, are listed in Table 1. The rotating impeller within the pump generates either axial flow (blood flow parallel to the impeller axis) or centrifugal flow (blood flow at a right angle to the impeller axis) from the left ventricular (LV) apex, through the device, to the ascending aorta. The HeartMate II (HM II; Thoratec Corp, Pleasanton, CA) is the only continuous-flow pump approved by the US Food and Drug Administration to act as a bridge to cardiac transplantation and as destination therapy. Operating speeds for this device are between 6000 and 15 000 revolutions per minute (rpm), which clinically translates …

Introduction: Pump thrombosis is a potentially life-threatening event that currently presents a diagnostic challenge. We therefore sought to explore the diagnostic utility and the association of measured cardiac computed tomography (CT) parameters in patients with LVAD malfunction due to pump thrombosis. Methods: From 2009 to 2013, 150 patients underwent placement of Heart Mate II continuous flow pump at our institution. Of these 52 patients, underwent cardiac CT with contrast either as part of a prospective protocol or for suspected malfunction. 14 patients had pump thrombosis per the INTERMACS criteria and the remaining were used as controls. Rigorous linear and area measurements for the inflow and outflow tracts of LVADs were performed. Results: The mean age of the population was 55 ± 11, 36 were male, and 28 had ischemic cardiomyopathy. Results are shown in table 1. For inflow cannula, measurement of axial area shown in figure 1, was significantly higher in the pump thrombosis group compared to the control group 31±16 cm2 vs 20 ± 12 cm2 (p=.02). Although, the difference in the acute angle for the inflow cannula relative to the perpendicular axis between the midpoint of the mitral annulus and tip of inflow cannulas was not significantly different between the two groups, there was a trend towards greater angulation in the pump thrombosis group (60 ± 6 vs 53 ± 15) and there was a positive correlation between both measurements r=0.513, p-value= 0.003. Conclusions: Area in the axial view of the ventricle at the site of the inflow cannula tip may be a surrogate for off axis placement of the cannula. This area may be helpful in predicting pump thrombosis in patients.

Background— Alcohol septal ablation (ASA) therapy results in clinical and hemodynamic improvement in patients with hypertrophic obstructive cardiomyopathy. However, a subset remains symptomatic afterward, requiring additional procedures. We sought to examine the determinants of an unsatisfactory outcome, defined as unchanged symptoms with Methods and Results— Of 173 consecutive hypertrophic obstructive cardiomyopathy patients who underwent ASA, 39 had an unsatisfactory outcome after the first procedure. Patients with an unsatisfactory outcome had a higher baseline LVOT gradient, fewer septal arteries injected with ethanol, lower peak creatine kinase (CK), smaller septal area opacified by contrast echocardiography, and higher residual gradient in the catheterization laboratory after ASA (all P P =0.01) and peak CK P =0.04) were the independent predictors of an unsatisfactory outcome. Conclusions— The residual LVOT gradient in the catheterization laboratory and peak CK leak after ASA are the independent predictors of ASA outcome.

Background— Patients with chronic kidney disease (CKD) have worse cardiovascular outcomes than those without CKD. The prognostic utility of myocardial perfusion single-photon emission CT (MPS) in patients with varying degrees of renal dysfunction and the impact of CKD on cardiac death prediction in patients undergoing MPS have not been investigated. Methods and Results— We followed up 1652 consecutive patients who underwent stress MPS (32% exercise, 95% gated) for cardiac death for a mean of 2.15±0.8 years. MPS defects were defined with a summed stress score (normal summed stress score −1 · 1.73 m −2 ) was present in 36%. Cardiac death increased with worsening levels of perfusion defects across the entire spectrum of renal function. Presence of ischemia was independently predictive of cardiac death, all-cause mortality, and nonfatal myocardial infarction. Patients with normal MPS and CKD had higher unadjusted cardiac death event rates than those with no CKD and normal MPS (2.7% versus 0.8%, P =0.001). Multivariate Cox proportional hazards models revealed that both perfusion defects (hazard ratio 1.90, 95% CI 1.47 to 2.46) and CKD (hazard ratio 1.96, 95% CI 1.29 to 2.95) were independent predictors of cardiac death after accounting for risk factors, left ventricular dysfunction, pharmacological stress, and symptom status. Both MPS and CKD had incremental power for cardiac death prediction over baseline risk factors and left ventricular dysfunction (global χ 2 207.5 versus 169.3, P Conclusions— MPS provides effective risk stratification across the entire spectrum of renal function. Renal dysfunction is also an important independent predictor of cardiac death in patients undergoing MPS. Renal function and MPS have additive value in risk stratisfying patients with suspected coronary artery disease. Patients with CKD appear to have a relatively less benign prognosis than those without CKD, even in the presence of a normal scan.

Over 5 million emergency department (ED) visits occur annually for evaluation of chest pain. A rapid simple imaging algorithm is needed to identify patients with noncardiac chest pain so as to avoid unnecessary hospital admission. We conducted a prospective trial in 1031 low risk patients (60% women; mean age 54±13 years) admitted through the ED to our chest pain unit who had no prior cardiac history, a nondiagnostic ECG for ischemia, and a normal initial troponin. All patients had stress myocardial perfusion imaging (SPECT) with a coronary artery calcium score (CACS) by noncontrast cardiac computed tomography (CT) within 24 hours. Mean patient follow-up was 7.4±3.3 months. SPECT and CT studies were interpreted independently and the CACS quantified as an Agatston score. The mean TIMI risk score was 1.5±0.7. Cardiac events occurred in 29 patients (2.8%): acute myocardial infarction (N=4) or an acute coronary syndrome (ACS, N=21) during admission; or ACS following hospital discharge (N=4). Abnormal SPECT and cardiac events significantly increased with CACS (p400 vs 0(Table ). Only 5 (0.8%) patients with CACS=0 had an abnormal SPECT and none had significant coronary artery disease by angiography. The 2 patients who had a CACS=0 and a cardiac event during their hospitalization both had a normal gated SPECT and no subsequent event in follow-up. The sensitivity of an abnormal CT was significantly higher than an abnormal SPECT for identifying patients with events (93% vs 65%, p