Ischemia and Viability Testing in New-Onset Heart Failure

Identifying Demographic and Clinical Determinants of Ischemic Workup in Patients with Heart Failure

Background/Objectives: Coronary artery disease (CAD) is a common and treatable cause of heart failure (HF), but ischemic evaluation is often overlooked when evaluating patients with new-onset HF. Here, we sought to discern demographic and clinical predictors of ischemic workup in patients with newly diagnosed HF. Methods: A retrospective study of 200 consecutive patients with new-onset HF admitted to our safety-net hospital between 2011 and 2015 was performed. We developed a multivariate logistic regression model to analyze determinants of undergoing ischemic evaluation. Results: A total of 99 patients (49.5%) underwent ischemic workup, while 101 patients (50.5%) did not. The mean age of the cohort was 73.9 ± 16, with 50% as male and 51% as White. In total, 41.5% of patients had HF with reduced ejection fraction, and 37% of patients had HF with preserved ejection fraction. Among the patients who underwent ischemic evaluation, 63.6% received nuclear stress testing, 24.2% received cardiac catheterization, 9.1% received stress echocardiography, and 3% received computed tomography angiography. Demographic and clinical factors such as sex, age, race, presence of hypertension, hyperlipidemia, chronic kidney disease, diabetes, or obesity had no significant association with receiving ischemic workup (p > 0.05). Patients with known CAD (OR 2.816, p = 0.015) and a higher social deprivation index (SDI) (OR 1.022, p = 0.003) were significantly more likely to receive an ischemic evaluation. Atrial fibrillation was significantly negatively associated with receiving ischemic workup (OR: 0.24; p = 0.001). Conclusions: In our single-center safety-net hospital analysis, known CAD and higher SDI were significant predictors of ischemic evaluation in patients with newly diagnosed HF. Multiple demographic features, including age, sex, race, and clinical features, including HF type, hypertension, hyperlipidemia, and diabetes, had no significant correlation with ischemic workup.

Imaging Advances in Heart Failure

This paper delves into the significance of imaging in the diagnosis, aetiology and therapeutic guidance of heart failure, aiming to facilitate early referral and improve patient outcomes. Imaging plays a crucial role not only in assessing left ventricular ejection fraction, but also in characterising the underlying cardiac abnormalities and reaching a specific diagnosis. By providing valuable data on cardiac structure, function and haemodynamics, imaging helps diagnose the condition, evaluate haemodynamic status and, consequently, identify the underlying pathophysiological phenotype, as well as stratifying the risk for outcomes. In this article, we provide a comprehensive exploration of these aspects.

Myocardial Viability Testing in the Management of Ischemic Heart Failure

Although major advances have occurred lately in medical therapy, ischemic heart failure remains an important cause of death and disability. Viable myocardium represents a cause of reversible ischemic left ventricular dysfunction. Coronary revascularization may improve left ventricular function and prognosis in patients with viable myocardium. Although patients with impaired left ventricular function and multi-vessel coronary artery disease benefit the most from revascularization, they are at high risk of complications related to revascularization procedure. An important element in selecting the patients for myocardial revascularization is the presence of the viable myocardium. Multiple imaging modalities can assess myocardial viability and predict functional improvement after revascularization, with dobutamine stress echocardiography, nuclear imaging tests and magnetic resonance imaging being the most frequently used. However, the role of myocardial viability testing in the management of patients with ischemic heart failure is still controversial due to the failure of randomized controlled trials of revascularization to reveal clear benefits of viability testing. This review summarizes the current knowledge regarding the concept of viable myocardium, depicts the role and tools for viability testing, discusses the research involving this topic and the controversies related to the utility of myocardial viability testing and provides a patient-centered approach for clinical practice.

The prognostic implications of ST-segment and T-wave abnormalities in patients undergoing regadenoson stress SPECT myocardial perfusion imaging

BACKGROUND

The prognostic implications of ST-segment and T-wave (ST/T) abnormalities in patients undergoing stress SPECT-myocardial perfusion imaging (MPI) are not well defined.

METHODS AND RESULTS

This was a single-center, retrospective cohort study of consecutive patients who underwent regadenoson stress SPECT-MPI. Patients with baseline electrocardiogram (ECG) abnormalities that impede ST/T analysis or those with known coronary artery disease were excluded. Patients were categorized as having primary ST abnormalities, secondary ST/T abnormalities due to ventricular hypertrophy or right bundle branch block, T-wave abnormalities, or normal ECG. The primary outcome was major adverse cardiovascular events (MACE) defined as the composite of cardiac death or myocardial infarction. Among 6,059 subjects, 1912 (32%) had baseline ST/T abnormalities. During a mean follow-up of 2.3 ± 1.9 years, the incidence of MACE was significantly higher among patients with secondary ST/T abnormalities compared to those with normal ECG (HR 2.05; 95% confidence interval [CI], 1.04-4.05; P = 0.039). No significant difference in MACE was observed among patients with primary ST abnormalities (HR 1.64; CI 0.87-3.06; P = 0.124) or T-wave abnormalities (HR 1.15; CI 0.62-2.16; P = 0.658) compared with patients who had normal ECG. Among patients with secondary ST/T changes, abnormal MPI was not associated with a significant increase in MACE rates compared to normal MPI (HR 1.18; CI 0.31-4.58; P = 0.808). However, abnormal MPI was associated with higher MACE rates among patients with primary ST abnormalities (HR 4.50; CI 1.44-14.10; P = 0.005) and T-wave abnormalities (HR 3.74; CI 1.20-11.68; P = 0.015). Similarly, myocardial ischemia on regadenoson stress SPECT-MPI was not associated with a significant increase in MACE rates in patients with secondary ST/T abnormalities (HR 1.45; CI 0.38-5.61; P = 0.588), while it was associated with a higher incidence of MACE in patients with primary ST abnormalities (HR 3.012; CI 0.95-9.53; P = 0.049) and T-wave abnormalities (HR 5.06; CI 1.60-15.96; P = 0.002).

CONCLUSION

While patients with secondary ST/T abnormalities had significantly higher MACE risk, abnormal MPI or presence of myocardial ischemia on regadenoson SPECT-MPI in this group does not add prognostic information. Patients with primary ST abnormalities and T-wave abnormalities do not seem to have a significantly higher MACE risk compared to those with normal ECG; however, abnormal MPI or presence of myocardial ischemia, in these groups, correlates with higher MACE rates.