Clinical and economic outcomes of pharmacological stress tests in patients with a history of COVID-19.

BACKGROUND: Despite millions of COVID-19 cases in the United States, it remains unknown whether a history of COVID-19 infection impacts the safety of pharmacologic myocardial perfusion imaging stress testing (pharmacologic MPI). HYPOTHESIS: The aim of this study was to assess if a prior COVID-19 infection was associated with a higher risk of complications during and following pharmacologic MPI testing. METHODS: This retrospective cohort analysis included 179 803 adults (≥18 years) from the PharMetrics® Plus claims database who underwent pharmacologic MPI between March 1, 2020 and February 28, 2021. Patients with a history of COVID-19 infection (COVID-19 group) were compared with propensity-score matched no-COVID-19 history group for reversal agent use, 30-day resource use, and post-MPI cardiac events/procedures. RESULTS: The most commonly used stress agent was regadenoson (91.7%). The COVID-19 group (n = 6372; 3.5%) had slightly higher: reversal agent use (difference 1.13% [95% confidence interval [CI]: 0.33, 1.92]), all-cause costs (difference USD $128 [95% CI: $73-$181]), and office visits (81.5% vs. 77.0%) than the no-COVID-19 group. Prior COVID-19 infection did not appear to impact subsequent cardiac events/procedures. CONCLUSIONS: COVID-19 history was associated with slightly higher reversal agent use, all-cause costs, and office visits after pharmacologic MPI; however, the differences were not clinically meaningful. Concerns for use of stress agents in patients with prior COVID-19 do not appear to be warranted.

Role of Exercise Treadmill Testing in the Assessment of Coronary Microvascular Disease.

OBJECTIVES: The authors aimed to study the sensitivity and specificity of exercise treadmill testing (ETT) in the diagnosis of coronary microvascular disease (CMD), as well as the prognostic implications of ETT results in patients with CMD. BACKGROUND: ETT is validated to evaluate for flow-limiting coronary artery disease (CAD), however, little is known about its use for evaluating CMD. METHODS: We retrospectively studied 249 consecutive patients between 2006 and 2016 who underwent ETT and positron emission tomography within 12 months. Patients with obstructive CAD or left ventricular systolic dysfunction were excluded. CMD was defined as a coronary flow reserve <2. Patients were followed for the occurrence of a first major adverse event (composite of death or hospitalization for myocardial infarction or heart failure). RESULTS: The sensitivity and specificity of a positive ETT to detect CMD were 34.7% (95% CI: 25.4%-45.0%) and 64.9% (95% CI: 56.7%-72.5%), respectively. The specificity of a positive ETT to detect CMD increased to 86.8% (95% CI: 80.3%-91.7%) when only classifying studies with ischemic electrocardiogram changes that lasted at least 1 minute into recovery as positive, although at a cost of lower sensitivity (15.3%; 95% CI: 8.8%-24.0%). Over a median follow-up of 6.9 years (IQR: 5.1-8.2 years), 30 (12.1%) patients met the composite endpoint, including 13 (13.3%) with CMD (n = 98). In patients with CMD, ETT result was not associated with the composite endpoint (P = 0.076). CONCLUSIONS: Our data suggest limited sensitivity of ETT to detect CMD. However, a positive ETT with ischemic changes that persist at least 1 minute into recovery in the absence of obstructive CAD should raise suspicion for the presence of CMD given a high specificity. Further study is needed with larger patient sample sizes to assess the association between ETT results and outcomes in patients with CMD.

Complementary Value of Cardiac Magnetic Resonance Imaging and Positron Emission Tomography/Computed Tomography in the Assessment of Cardiac Sarcoidosis.

BACKGROUND: Although cardiac magnetic resonance (CMR) and positron emission tomography (PET) detect different pathological attributes of cardiac sarcoidosis (CS), the complementary value of these tests has not been evaluated. Our objective was to determine the value of combining CMR and PET in assessing the likelihood of CS and guiding patient management. METHODS AND RESULTS: In this retrospective study, we included 107 consecutive patients referred for evaluation of CS by both CMR and PET. Two experienced readers blinded to all clinical data reviewed CMR and PET images and categorized the likelihood of CS as no (<10%), possible (10%-50%), probable (50%-90%), or highly probable(>90%) based on predefined criteria. Patient management after imaging was assessed for all patients and across categories of increasing CS likelihood. A final clinical diagnosis for each patient was assigned based on a subsequent review of all available imaging, clinical, and pathological data. Among 107 patients (age, 55±11 years; left ventricular ejection fraction, 43±16%), 91 (85%) had late gadolinium enhancement, whereas 82 (76%) had abnormal F18-fluorodeoxyglucose uptake on PET, suggesting active inflammation. Among the 91 patients with positive late gadolinium enhancement, 60 (66%) had abnormal F18-fluorodeoxyglucose uptake. When PET data were added to CMR, 48 (45%) patients were reclassified as having a higher or lower likelihood of CS, most of them (80%) being correctly reclassified when compared with the final diagnosis. Changes in immunosuppressive therapies were significantly more likely among patients with highly probable CS. CONCLUSIONS: Among patients with suspected CS, combining CMR and PET provides complementary value for estimating the likelihood of CS and guiding patient management.

Assessment of myocardial viability and left ventricular function in patients supported by a left ventricular assist device.

BACKGROUND: Chronically supported left ventricular assist device (LVAD) patients may be candidates for novel therapies aimed at promoting reverse remodeling and myocardial recovery. However, the effect of hemodynamic unloading with a LVAD on myocardial viability and LV function in chronically supported LVAD patients has not been fully characterized. We aimed to develop a non-invasive imaging protocol to serially quantify native cardiac structure, function, and myocardial viability while at reduced LVAD support. METHODS: Clinically stable (n = 18) ambulatory patients (83% men, median age, 61 years) supported by a HeartMate II (Thoratec, Pleasanton, CA) LVAD (median durations of heart failure 4.6 years and LVAD support 7 months) were evaluated by echocardiography and technetium-99m ((99m)Tc)-sestamibi single photon emission computed tomography (SPECT) imaging at baseline and after an interval of 2 to 3 months. Echocardiographic measures of LV size and function, including speckle tracking-derived circumferential strain, were compared between ambulatory and reduced LVAD support at baseline and between baseline and follow-up at reduced LVAD support. The extent of myocardial viability by SPECT was compared between baseline and follow-up at reduced LVAD support. RESULTS: With reduction in LVAD speeds (6,600 rpm; interquartile range: 6,200, 7,400 rpm), LV size increased, LV systolic function remained stable, and filling pressures nominally worsened. After a median 2.1 months, cardiac structure, function, and the extent of viable myocardium, globally and regionally, was unchanged on repeat imaging while at reduced LVAD speed. CONCLUSIONS: In clinically stable chronically supported LVAD patients, intrinsic cardiac structure, function, and myocardial viability did not significantly change over the pre-specified time frame. Echocardiographic circumferential strain and (99m)Tc-sestamibi SPECT myocardial viability imaging may provide useful non-invasive end points for the assessment of cardiac structure and function, particularly for phase II studies of novel therapies aimed at promoting reverse remodeling and myocardial recovery in LVAD patients.

18F-FDG PET/CT for the assessment of myocardial sarcoidosis.

Cardiac involvement portends a poor prognosis inpatients with sarcoidosis. However, due to the non specific clinical manifestations of the disease, patchy myocardial involvement, and the limited diagnostic yield of diagnostic tests, early diagnosis of cardiac sarcoidosis has been exceedingly difficult. As a result, there is no standardized approach for the early diagnosis of cardiac sarcoidosis. Imaging modalities that can both identify disease and predict response to therapy are paramount to improve management of cardiac sarcoidosis. 18F-FDG PET has many practical advantages in assessing disease activity and monitoring treatment response in patients with cardiac sarcoidosis. Accumulating data support the growing role of 18F-fluorodeoxyglucose (18F-FDG)PET in the diagnosis and risk stratification of patients with cardiac sarcoidosis.

(18)F-FDG PET/CT for the assessment of myocardial sarcoidosis.

Cardiac involvement portends a poor prognosis in patients with sarcoidosis. However, due to the nonspecific clinical manifestations of the disease, patchy myocardial involvement, and the limited diagnostic yield of diagnostic tests, early diagnosis of cardiac sarcoidosis has been exceedingly difficult. As a result, there is no standardized approach for the early diagnosis of cardiac sarcoidosis. Imaging modalities that can both identify disease and predict response to therapy are paramount to improve management of cardiac sarcoidosis. (18)F-FDG PET has many practical advantages in assessing disease activity and monitoring treatment response in patients with cardiac sarcoidosis. Accumulating data support the growing role of (18)F-fluorodeoxyglucose ((18)F-FDG) PET in the diagnosis and risk stratification of patients with cardiac sarcoidosis.

Association of heart rate and outcomes in a broad spectrum of patients with chronic heart failure: results from the CHARM (Candesartan in Heart Failure: Assessment of Reduction in Mortality and morbidity) program.

OBJECTIVES: The aim of this study was to explore the relationship between baseline resting heart rate and outcomes in patients with chronic heart failure (HF) according to baseline left ventricular ejection fraction (LVEF) and cardiac rhythm. BACKGROUND: Elevated resting heart rate is associated with worse outcomes in patients with HF and reduced LVEF. Whether this association is also found in patients with HF and preserved LVEF is uncertain, as is the predictive value of heart rate in patients in atrial fibrillation (AF). METHODS: Patients enrolled in the CHARM (Candesartan in Heart failure: Assessment of Reduction in Mortality and morbidity) Program were divided into groups by tertiles of baseline heart rate. Cox proportional hazard models were used to investigate the association between heart rate and pre-specified outcomes in the overall population as well as in subgroups defined according to LVEF (≤ 40% vs. >40%) and presence (or absence) of AF at baseline. RESULTS: After adjusting for predictors of poor prognosis, patients in the highest heart rate tertile had worse outcomes when compared with those in the lowest heart rate group (e.g., for the composite of cardiovascular death or HF hospital stay hazard ratio: 1.23, 95% confidence interval: 1.11 to 1.36, p < 0.001). The relationship between heart rate and outcomes was similar across LVEF categories and was not influenced by beta-blocker use (p value for interaction >0.10 for both endpoints). However, amongst patients in AF at baseline, heart rate had no predictive value (p value for interaction <0.001). CONCLUSIONS: Resting heart rate is an important predictor of outcome in patients with stable chronic HF without AF, regardless of LVEF or beta-blocker use.

Prognostic assessment of estimated glomerular filtration rate by the new Chronic Kidney Disease Epidemiology Collaboration equation in comparison with the Modification of Diet in Renal Disease Study equation.

BACKGROUND: Systematic reporting of estimated glomerular filtration rate (eGFR) using the Modification of Diet in Renal Disease (MDRD) Study equation is recommended for detection of chronic kidney disease and prediction of cardiovascular (CV) risk. The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation is a newly developed and validated formula for eGFR that is more accurate at normal or near-normal eGFR. We aimed to assess the incremental prognostic accuracy of eGFR(CKD-EPI) versus eGFR(MDRD) in subjects at increased risk for CV disease. METHODS: We performed a post hoc analysis of the VALIANT trial that enrolled 14,527 patients with acute myocardial infarction with signs and symptoms of heart failure and/or left ventricular systolic dysfunction. The eGFR(MDRD) and eGFR(CKD-EPI) were computed using age, gender, race, and baseline creatinine level. Patients were categorized according to their eGFR using each equation. To assess the incremental prognostic value of eGFR(CKD-EPI), the net reclassification improvement was calculated for the composite end point of CV death, recurrent myocardial infarction, heart failure, or stroke. RESULTS: Twenty-four percent of the subjects were reclassified into a different eGFR category using eGFR(CKD-EPI). The composite end point occurred in 33% of the subjects in this cohort. Based on eGFR(CKD-EPI), subjects reclassified into a higher eGFR experienced fewer events than those reclassified into a lower eGFR (21% vs 43%). In unadjusted analyses, the composite end point risk in subjects with eGFR between 75 and 90 mL/min per 1.73 m(2) was comparable with the referent group (eGFR between 90 and 105) using eGFR(MDRD) (hazard ratio 1.1, 95% CI 0.9-1.2) but was significantly higher using eGFR(CKD-EPI) (hazard ratio 1.2, 95% CI 1.1-1.4). The net reclassification improvement for eGFR(CKD-EPI) over eGFR(MDRD) was 8.7%. CONCLUSION: The CKD-EPI equation provides more accurate risk stratification than the MDRD Study equation in patients at high risk for CV disease, including identification of increased risk at mildly decreased eGFR.

Incremental value of echocardiographic assessment beyond clinical evaluation for prediction of death and development of heart failure after high-risk myocardial infarction.

BACKGROUND: Echocardiographic measurements of left ventricular (LV) function, predominantly LV ejection fraction (LVEF), have been used to define risk in patients after myocardial infarction. However, the extent to which measures of LV structure and function provide incremental prognostic value over clinical variables in survivors of high-risk myocardial infarction has not been well defined. METHODS: Predictors of death and development of heart failure were assessed in 603 patients from the Valsartan in Acute Myocardial Infarction (VALIANT) echocardiographic substudy. We used multivariable proportional hazards models to assess the individual predictive value of echocardiographic measures including left ventricular mass index, LVEF, LV volumes, left atrial volume index, right ventricular fractional area change, mitral regurgitation, and deceleration time. We adjusted for the 11 clinical variables found previously to be most associated with all-cause mortality in this cohort. Receiver operating characteristic curves obtained via binary response regression were used to assess the incremental predictive value of echocardiographic measures in predicting outcomes of death and hospital stay for heart failure. RESULTS: Each echocardiographic measure was independently associated with outcome of death or development of heart failure (all P < .002). Left ventricular ejection fraction alone added minimal prognostic value to the clinical assessment, yet adding additional echocardiographic assessments to a multivariable model improved in predicting 17-month survival free of heart failure significantly, increasing the c-statistic from 0.74 to 0.84 (P < .001). CONCLUSION: Echocardiographic measures of cardiac structure and function beyond LVEF provide important prognostic information beyond the clinical assessment.

Novel techniques for assessment of left ventricular systolic function.

The evaluation of left ventricular systolic function is one of the most common reasons for referral for a non-invasive cardiac imaging study. In addition to its diagnostic and prognostic value, an assessment of ejection fraction can also be used to guide medical and device therapy. Thus, obtaining an accurate and reproducible assessment of LVEF is essential for patient management. This review will focus on novel multi-modality techniques used for the quantification of left ventricular systolic function. Emerging echocardiography techniques such as three-dimensional echocardiography and strain imaging and their incremental role over traditional 2D imaging will be discussed. In addition, new developments expanding nuclear imaging techniques' evaluation of left ventricular systolic function will be reviewed. Finally, an overview of advances in imaging techniques such as cardiac magnetic resonance and cardiac computed tomography, which now allow for an accurate and highly reproducible assessment of LVEF, will be presented.

Body mass index and prognosis in patients with chronic heart failure: insights from the Candesartan in Heart failure: Assessment of Reduction in Mortality and morbidity (CHARM) program.

BACKGROUND: In individuals without known cardiovascular disease, elevated body mass index (BMI) (weight/height2) is associated with an increased risk of death. However, in patients with certain specific chronic diseases, including heart failure, low BMI has been associated with increased mortality. METHODS AND RESULTS: We examined the influence of BMI on prognosis using Cox proportional hazards models in 7599 patients (mean age, 65 years; 35% women) with symptomatic heart failure (New York Heart Association class II to IV) and a broad spectrum of left ventricular ejection fractions (mean, 39%) in the Candesartan in Heart failure: Assessment of Reduction in Mortality and morbidity (CHARM) program. During a median follow-up of 37.7 months, 1831 patients died. After adjustment for potential confounders, compared with patients with BMI between 30 and 34.9, patients in lower BMI categories had a graded increase in the risk of death. The hazard ratios (95% confidence intervals) were 1.22 (1.06 to 1.41), 1.46 (1.24 to 1.71), and 1.69 (1.43 to 2.01) among those with BMI of 25 to 29.9, 22.5 to 24.9, and < 22.5, respectively. The increase in risk of death among patients with BMI > or = 35 was not statistically significant (hazard ratio, 1.17; 95% confidence interval, 0.95 to 1.43). The association between BMI and mortality was not altered by age, smoking status, or left ventricular ejection fraction (P for interaction >0.20). However, lower BMI was associated with a greater risk of all-cause death in patients without edema but not in patients with edema (P for interaction <0.0001). Lower BMI was associated with a greater risk of cardiovascular death and noncardiovascular death. Baseline BMI did not influence the risk of hospitalization for worsening heart failure or due to all causes. CONCLUSIONS: In patients with symptomatic heart failure and either reduced or preserved left ventricular systolic function, underweight or low BMI was associated with increased mortality, primarily in patients without evidence of fluid overload (edema).

Two-dimensional assessment of right ventricular function: an echocardiographic-MRI correlative study.

BACKGROUND: While echocardiography is used most frequently to assess right ventricular (RV) function in clinical practice, echocardiography is limited in its ability to provide an accurate measure of RV ejection fraction (RVEF). Hence, quantitative estimation of RV function has proven difficult in clinical practice. OBJECTIVE: We sought to determine which commonly used echocardiographic measures of RV function were most accurate in comparison with an MRI-derived estimate of RVEF. METHODS: We analyzed RV function in 36 patients who had cardiac MRI studies and echocardiograms within a 24 hour period. 2D parameters of RV function-right ventricular fractional area change (RVFAC), tricuspid annular motion (TAM), and transverse fractional shortening (TFS) were obtained from the four-chamber view. RV volumes and EFs were derived from volumetric reconstruction based on endocardial tracing of the RV chamber from the short axis images. Echocardiographic assessment of RV function was correlated with MRI findings. RESULTS: RVFAC measured by echocardiography correlated best with MRI-derived RVEF (r = 0.80, P < 0.001). Neither TAM (r = 0.17; P = 0.30) nor TFC (r = 0.12; p< 0.38) were significantly correlated with RVEF. CONCLUSIONS: RVFAC is the best of commonly utilized echocardiographic 2D measure of RV function and correlated best with MRI-derived RV ejection fraction. CONDENSED ABSTRACT: While echocardiography is used most frequently to assess RV function in clinical practice, echocardiography is limited in its ability to provide an accurate measure of RV ejection fraction (RVEF). Using cardiac MRI, RV fractional area change (RVFAC), determined either by MRI or echocardiography, was found to correlate best with MRI-derived RVEF.

Comparison of regional versus global assessment of left ventricular function in patients with left ventricular dysfunction, heart failure, or both after myocardial infarction: the valsartan in acute myocardial infarction echocardiographic study.

BACKGROUND: Left ventricular (LV) ejection fraction (EF) and wall-motion index (WMI) have both been shown to be independent predictors of outcome after myocardial infarction (MI). OBJECTIVES: We sought to determine whether these two measurements of LV systolic function provide similar or complementary information about prognosis after MI. METHODS: Echocardiography was performed in 610 patients with LV dysfunction, heart failure, or both after MI enrolled in the Valsartan in Acute MI trial. LVEF was estimated by biplane Simpson's rule, and WMI was assessed using a 16-segment model in 502 patients with echocardiograms of sufficient quality for wall-motion assessment. RESULTS: Both LVEF and WMI were independent predictors of adverse outcome after MI. LVEF conferred no additional prognostic information in multivariable analysis including WMI (P = .39) or number of affected segments (P = .53), whereas WMI (P = .02) and total number of affected segments (P = .006) remained significant even when adjusting for LVEF. CONCLUSIONS: Assessment of regional dysfunction by WMI or the number of affected segments has slightly more prognostic value than LVEF in patients with LV dysfunction, heart failure, or both after MI. Regional assessment might be a more sensitive predictor of outcome than global assessment in patients with acute MI.

Risk assessment in patients with depressed left ventricular function after myocardial infarction using the myocardial performance index--Survival and Ventricular Enlargement (SAVE) experience.

BACKGROUND: Myocardial performance index (MPI) is a noninvasive, quantitative Doppler measure of global cardiac function, integrating systolic and diastolic functions. The prognostic significance of MPI is less clear for cardiovascular (CV) events after myocardial infarction (MI) among individuals at high risk with depressed left ventricular (LV) systolic function. METHODS: We analyzed echocardiograms from 512 patients with depressed LV function after MI enrolled in the Survival and Ventricular Enlargement (SAVE) echocardiographic substudy. Baseline MPI measures were obtainable in 226 patients. The cohort was separated by median MPI (0.50). MPI was related to baseline clinical and echocardiographic characteristics, ventricular remodeling, and subsequent CV events, including recurrent MI, heart failure, CV death, and a composite of all CV end points. RESULTS: An MPI of 0.5 or more was associated with larger infarct size and reduced LV systolic function at baseline; other baseline characteristics between the groups were similar. A total of 64 (28.3%) patients experienced CV events. Baseline MPI did not influence ventricular remodeling and did not modify the relationship between ventricular dilatation and CV events. After covariate adjustment, an MPI of 0.50 or higher remained an independent predictor for adverse CV events (hazard ratio [HR], 2.00, 95% confidence interval 1.17-3.43). CONCLUSIONS: An MPI of 0.50 or greater is an independent predictor for CV events after MI in patients with known LV dysfunction.

Effect of candesartan on cause-specific mortality in heart failure patients: the Candesartan in Heart failure Assessment of Reduction in Mortality and morbidity (CHARM) program.

BACKGROUND: Patients with heart failure are at increased risk of sudden death and death attributed to progressive pump failure. We assessed the effect of candesartan on cause-specific mortality in patients enrolled in the Candesartan in Heart failure Assessment of Reduction in Mortality and morbidity (CHARM) program. METHODS AND RESULTS: The CHARM program consisted of 3 component trials that enrolled patients with symptomatic heart failure: CHARM-Alternative (n=2028; LVEF<=40% [corrected] and ACE intolerant), CHARM-Added (n=2548; LVEF<=40%, [corrected] already on ACE inhibitors), and CHARM-Preserved (n=3023; LVEF >40%). Patients were randomized to candesartan, titrated to 32 mg QD, or placebo and were followed up for a median of 37.7 months. All deaths were reviewed by a blinded adjudication committee and categorized according to prespecified definitions on the basis of a narrative and source documentation. The number and rate of deaths by cause were calculated for each of the component trials and the overall program. Of all the patients, 8.5% died suddenly, and 6.2% died of progressive heart failure. Candesartan reduced both sudden death (HR 0.85 [0.73 to 0.99], P=0.036) and death from worsening heart failure (HR 0.78 [0.65 to 0.94], P=0.008). These reductions were most apparent in the patients with LVEF<=40% [corrected]. CONCLUSIONS: Candesartan reduced sudden death and death from worsening heart failure in patients with symptomatic heart failure, although this reduction was most apparent in patients with systolic dysfunction.