Cases from a busy nuclear cardiology laboratory: Potential pitfalls in the interpretation of cardiac scintigraphy for ATTR cardiac amyloidosis.

Cardiac scintigraphy has emerged as a key diagnostic test for transthyretin cardiac amyloidosis (ATTR-CA). However, there are potential limitations and pitfalls in the interpretation of cardiac scintigraphy for ATTR-CA that are worth noting. We present here a series of three cases which illustrate some of these important principles.

Myocardial Viability and Long-Term Outcomes in Ischemic Cardiomyopathy.

Background: The role of assessment of myocardial viability in identifying patients with ischemic cardiomyopathy who might benefit from surgical revascularization remains controversial. Furthermore, although improvement in left ventricular function is one of the goals of revascularization, its relationship to subsequent outcomes is unclear.

Methods: Among 601 patients who had coronary artery disease that was amenable to coronary-artery bypass grafting (CABG) and who had a left ventricular ejection fraction of 35% or lower, we prospectively assessed myocardial viability using single-photon-emission computed tomography, dobutamine echocardiography, or both.

Variability in Ejection Fraction Measured By Echocardiography, Gated Single-Photon Emission Computed Tomography, and Cardiac Magnetic Resonance in Patients With Coronary Artery Disease and Left Ventricular Dysfunction.

Importance: Clinical decisions are frequently based on measurement of left ventricular ejection fraction (LVEF). Limited information exists regarding inconsistencies in LVEF measurements when determined by various imaging modalities and the potential impact of such variability.

Objective: To determine the intermodality variability of LVEF measured by echocardiography, gated single-photon emission computed tomography (SPECT), and cardiovascular magnetic resonance (CMR) in patients with left ventricular dysfunction.

Regional left ventricular function does not predict survival in ischaemic cardiomyopathy after cardiac surgery.

Objectives: To define the prognostic contribution of global and regional left ventricular (LV) function measurements in patients with ischaemic cardiomyopathy randomised to coronary artery bypass graft surgery (CABG) with (n=501) or without (n=499) surgical ventricular reconstruction (SVR).

Methods: Novel multivariable methods to analyse global and regional LV systolic function were used to better formulate prediction models for long-term mortality following CABG with or without SVR in the entire cohort of 1000 randomised SVR hypothesis patients. Key clinical variables were included in the analysis.

Frailty Status and Outcomes After Transcatheter Aortic Valve Implantation.

Frailty is a syndrome of older adults associated with increased morbidity and mortality. We aimed to assess the impact of frailty status on outcomes after transcatheter aortic valve implantation (TAVI). We reviewed all 191 patients who underwent a modified Fried frailty assessment before TAVI between February 2012 and September 2015 at a single academic medical center, and we assessed the impact of preoperative frailty status on morbidity, mortality, and health care utilization after TAVI.

Severity of Remodeling, Myocardial Viability, and Survival in Ischemic LV Dysfunction After Surgical Revascularization.

Objectives: This study sought to test the hypothesis that end-systolic volume (ESV), as a marker of severity of left ventricular (LV) remodeling, influences the relationship between myocardial viability and survival in patients with coronary artery disease and LV systolic dysfunction.

Background: Retrospective studies of ischemic LV dysfunction suggest that the severity of LV remodeling determines whether myocardial viability predicts improved survival with surgical compared with medical therapy, with coronary artery bypass grafting (CABG) only benefitting patients with viable myocardium who have smaller ESV. However, this has not been tested prospectively.

The feasibility of imaging myocardial ischemic/reperfusion injury using (99m)Tc-labeled duramycin in a porcine model.

Unlabelled: When pathologically externalized, phosphatidylethanolamine (PE) is a potential surrogate marker for detecting tissue injuries. (99m)Tc-labeled duramycin is a peptide-based imaging agent that binds PE with high affinity and specificity. The goal of the current study was to investigate the clearance kinetics of (99m)Tc-labeled duramycin in a large animal model (normal pigs) and to assess its uptake in the heart using a pig model of myocardial ischemia-reperfusion injury.

Myocardial viability and impact of surgical ventricular reconstruction on outcomes of patients with severe left ventricular dysfunction undergoing coronary artery bypass surgery: results of the Surgical Treatment for Ischemic Heart Failure trial.

Objectives: In the Surgical Treatment for Ischemic Heart Failure trial, surgical ventricular reconstruction plus coronary artery bypass surgery was not associated with a reduction in the rate of death or cardiac hospitalization compared with bypass alone. We hypothesized that the absence of viable myocardium identifies patients with coronary artery disease and left ventricular dysfunction who have a greater benefit with coronary artery bypass graft surgery and surgical ventricular reconstruction compared with bypass alone.

Methods: Myocardial viability was assessed by single photon computed tomography in 267 of the 1000 patients randomized to bypass or bypass plus surgical ventricular reconstruction in the Surgical Treatment for Ischemic Heart Failure.

Inducible myocardial ischemia and outcomes in patients with coronary artery disease and left ventricular dysfunction.

Objectives: The study objectives were to test the hypotheses that ischemia during stress testing has prognostic value and identifies those patients with coronary artery disease (CAD) with left ventricular (LV) dysfunction who derive the greatest benefit from coronary artery bypass grafting (CABG) compared with medical therapy.

Background: The clinical significance of stress-induced ischemia in patients with CAD and moderately to severely reduced LV ejection fraction (EF) is largely unknown.

Methods: The STICH (Surgical Treatment for IsChemic Heart Failure) trial randomized patients with CAD and EF ≤35% to CABG or medical therapy.

Insights from the STICH trial: change in left ventricular size after coronary artery bypass grafting with and without surgical ventricular reconstruction.

Objective: The present analysis of the Surgical Treatment for Ischemic Heart Failure randomized trial data examined the left ventricular volumes at baseline and 4 months after surgery to determine whether any magnitude of postoperative reduction in end-systolic volume affected survival after coronary artery bypass grafting alone compared with bypass grafting plus surgical ventricular reconstruction.

Methods: Of the 1000 patients randomized, 555 underwent an operation and had a paired imaging assessment with the same modality at baseline and 4 months postoperatively. Of the remaining 455 patients, 424 either died before the 4-month study or did not have paired imaging tests and were excluded, and 21 were not considered because they had died before surgery or did not receive surgery.