The Prognostic Value of the Diastolic Stress Test in Patients Undergoing Treadmill Stress Echocardiography

The LATE score: A novel framework for echocardiographic evaluation of left ventricular filling pressure

BACKGROUND

The LATE score (LATE: Left Atrial reservoir strain (LASr), Tricuspid regurgitation maximum velocity (TR Vmax), and E/e' average) is a novel framework for echocardiographic assessment of left ventricular filling pressure (LVFP). LATE = 0 indicates normal LVFP. LATE = 1 indicates resting LVFP is borderline elevated, and the patient may be at risk of pathological elevation of LVFP during exertion. LATE ≥2 indicates LVFP is severely elevated.

METHODS

The LATE score was derived from reported thresholds of LASr and conventional echocardiographic parameters for predicting LVFP. The LATE score was prospectively evaluated in a cross-sectional study of 63 patients undergoing transthoracic echocardiography immediately prior to cardiac catheterization with invasive assessment of LVFP. Accuracy of the LATE score was compared to 2016 ASE diastology algorithms.

RESULTS

Mean patient age was 62.9 ± 13.6 years with 22% female. LATE = 0 in 29 patients, of which 24 (83%) had normal LVFP (mean LVFP 9 mmHg, SD ±3 mmHg). LATE = 1 in 23 patients, of which 11 (48%) had elevated LVFP (mean LVFP 12 mmHg, SD ± 4 mmHg). LATE was ≥2 in 11 patients, all of which had elevated LVFP (100%) (mean LVFP 16 mmHg, SD ±3 mmHg). The LATE score showed greater agreement with invasive assessment than the 2016 algorithms (LATE kappa = 0.73, 2016 kappa = 0.37).

CONCLUSIONS

The LATE score is a simple and effective tool for evaluation of LVFP that is more accurate than the 2016 algorithms. The LATE score provides insight beyond binary classification of normal versus elevated LVFP.

Isovolumic Contraction Velocity in Heart Failure With Reduced Ejection Fraction and Effect of Sacubitril/Valsartan: the PROVE-HF Study

OBJECTIVES

To assess tissue Doppler-derived mitral annular isovolumic contraction velocity (ICV) after starting sacubitril/valsartan (sac/val) for the treatment of heart failure with reduced ejection fraction (HFrEF) and left ventricular [LV] EF < 40%).

BACKGROUND

ICV may inform load-independent systolic function; combining ICV and LVEF may improve assessment of LV contractility.

METHODS

Among 651 participants with HFrEF treated with sac/val, echocardiograms were performed at baseline, 6 and 12 months. Pretreatment median ICVs and LVEFs were used for classification to predict LV reverse remodeling, health status using the Kansas City Cardiomyopathy Questionnaire, and biomarker concentrations.

RESULTS

The mean age was 64.6 ± 12.4 years, and 28% were women, baseline LVEF: 28.9% ± 6.9%. Compared to baseline, median ICV increased post sac/val therapy (4.6 [3.5, 6.1] vs 4.9 [3.6, 6.4]; P = 0.005). ICV added value to separate and combined models of biomarkers and clinical and echocardiographic variables for prediction of post-therapy EF recovery. Classification using baseline ICV/EF yielded relatively equal numbers in 4 groups based on low/high ICV or LVEF. Most deleterious results for remodeling, health status and biomarkers were found in patients with low ICV/low EF, whereas patients with high ICV/high EF had the best profiles; other groups were intermediate. Significant shifts toward better ICV/EF profiles were noted post sac/val treatment compared to baseline, with doubling of high ICV/high EF (241 [60%] vs 123 [31%]) and 78% reduction of low ICV/low EF (28 [7%] vs 125 [32%]).

CONCLUSIONS

In HFrEF, ICV adds to the profiling of systolic function and represents an independent predictor of reverse cardiac remodeling after treatment with sac/val. ICV changes may be used for assessment of treatment responses.

Prognostic Significance of Elevated Left Ventricular Filling Pressures with Exercise: Insights from a Cohort of 14,338 Patients

BACKGROUND

Exercise echocardiography can assess for cardiovascular causes of dyspnea other than coronary artery disease. However, the prevalence and prognostic significance of elevated left ventricular (LV) filling pressures with exercise is understudied.

METHODS

We evaluated 14,338 patients referred for maximal symptom-limited treadmill echocardiography. In addition to assessment of LV regional wall motion abnormalities (RWMAs), we measured patients' early diastolic mitral inflow (E), septal mitral annulus relaxation (e'), and peak tricuspid regurgitation velocity before and immediately after exercise.

RESULTS

Over a mean follow-up of 3.3 ± 3.4 years, patients with E/e' ≥15 with exercise (n = 1,323; 9.2%) had lower exercise capacity (7.3 ± 2.1 vs 9.1 ± 2.4 metabolic equivalents, P < .0001) and were more likely to have resting or inducible RWMAs (38% vs 18%, P < .0001). Approximately 6% (n = 837) had elevated LV filling pressures without RWMAs. Patients with a poststress E/e' ≥15 had a 2.71-fold increased mortality rate (2.28-3.21, P < .0001) compared with those with poststress E/e' ≤ 8. Those with an E/e' of 9 to 14, while at lower risk than the E/e' ≥15 cohort (hazard ratio [HR] = 0.58 [0.48-0.69]; P < .0001), had higher risk than if E/e' ≤8 (HR = 1.56 [1.37-1.78], P < .0001). On multivariable analysis, adjusting for age, sex, exercise capacity, LV ejection fraction, and presence of pulmonary hypertension with stress, patients with E/e' ≥15 had a 1.39-fold (95% CI, 1.18-1.65, P < .0001) increased risk of all-cause mortality compared with patients without elevated LV filling pressures. Compared with patients with E/e' ≤ 15 after exercise, patients with E/e' ≤15 at rest but elevated after exercise had a higher risk of cardiovascular death (HR = 8.99 [4.7-17.3], P < .0001).

CONCLUSION

Patients with elevated LV filling pressures are at increased risk of death, irrespective of myocardial ischemia or LV systolic dysfunction. These findings support the routine incorporation of LV filling pressure assessment, both before and immediately following stress, into the evaluation of patients referred for exercise echocardiography.

Association of Echocardiographic Parameter E/e' With Cardiovascular Events in a Diverse Population of Inpatients and Outpatients With and Without Cardiac Diseases and Risk Factors

BACKGROUND

The echocardiographic parameter E/e' has been associated with cardiovascular (CV) events. However, few studies have analyzed multiple associated CV outcomes using E/e' in a diverse population of both inpatients and outpatients with and without cardiac diseases and risk factors.

METHODS

Medical records of 75,393 patients without atrial fibrillation (AF) with first available E/e' were retrieved from our hospital database. Patients with mitral valve disease were excluded, and the remainder were studied in protocol 1 (70,819 patients). Patients with hypertension, diabetes mellitus, hyperlipidemia, CV diseases, prior CV events, CV surgeries, and left ventricular ejection fraction <50% or missing left ventricular ejection fraction were further excluded, and the remaining patients were studied in protocol 2 (14,665 patients). The study outcomes are major adverse CV events (MACE), which included myocardial infarction (MI), AF, ischemic and hemorrhagic stroke (IHS), hospitalization for heart failure (HHF), and cardiac death. The primary outcomes were MACE and each of the MACE components.

RESULTS

At the end of maximal 5-year follow-up (median 22.18 months with interquartile range 7.20-49.08 months for MACE in protocol 1 and 23.46 months with interquartile range 8.15-49.02 months for MACE in protocol 2), compared with an E/e' value of <8, an intermediate value of E/e' 8 to 15 and a high value of E/e' >15 were significantly associated with MACE, MI, AF, IHS, HHF, and cardiac death in protocol 1 (all P < .0001). In protocol 2, an intermediate E/e' value of 8 to 15 and a high value of E/e' >15 were significantly associated with MACE, MI, AF, IHS, HHF, and CV death (all P < .05), except an intermediate value E/e' 8 to 15 was not associated with AF.

CONCLUSIONS

In a diverse population of inpatients and outpatients with and without cardiac diseases and risk factors, the echocardiographic parameter E/e' was associated with CV events and is a useful marker of risk.

Additive prognostic and diagnostic value of diastolic exercise parameters in patients referred for exercise echocardiography

AIMS

Exercise echocardiography (ExE) may evaluate left ventricular (LV) systolic and diastolic function. We aimed to assess the value of diastolic parameters at exercise [early LV inflow velocity to early tissue Doppler annulus velocity (E/e')] in patients with normal or abnormal resting diastolic function (DF) referred for a clinically indicated ExE.

METHODS AND RESULTS

LV systolic and DF according to ASE/EACVI guidelines and mitral regurgitation (MR) were evaluated at rest in 772 patients (age 67 ± 12 years) with preserved LV ejection fraction (LVEF ≥ 50%). We assessed regional/global LV systolic function at peak exercise, while MR and E/e' where evaluated in the immediate post-exercise period. Abnormal ExE was defined as ischaemia or fixed wall motion abnormalities, and raised E/e' values as >15 at rest and at exercise (e' at the septal level). Patients were grouped as complaining or not of dyspnoea. Events were overall mortality, myocardial infarction, admission for unstable angina or cardiac failure, and coronary revascularization. DF was abnormal at rest in 221 patients (29%) and indeterminate in 77 (10%), with similar percentages in patients with and without dyspnoea. Exercise E/e' >15 was found in 37% of patients with abnormal DF, 21% with indeterminate DF, and 6% with normal DF (P < 0.001). Patients with abnormal ExE had more often abnormal resting DF (39% vs. 25%, P = 0.001) and exercise E/e' >15 (25% vs. 13%, P < 0.001) than those with normal ExE. During a median follow-up of 1.68 years, there were 132 events. Independent predictors included peak exercise LVEF [hazard ratio (HR) = 0.93, 95% confidence interval (CI) = 0.91-0.94, P < 0.001], and exercise E/e' (HR= 1.04, 95% CI = 1.01-1.07, P = 0.01). Neither resting E/e' values nor resting abnormal DF by ASE/EACVI guidelines, were independent predictors. Annualized event-rates were 43.2% in patients with (+) ExE plus (+) exercise E/e', 23.8% in those with (+) ExE and (-) exercise E/e', 7.9% in (-) ExE and (+) exercise E/e', and 3.6% with both variables normal.

CONCLUSIONS

The results of diastolic dysfunction at rest and at exercise were similar between patients with or without dyspnoea referred for ExE, but they were associated with abnormal ExE. Exercise E/e' reclassified 21% of patients with indeterminate DF and further predicted outcome on top of ExE results.

Does diabetes increase the risk of cardiovascular events in patients with negative treadmill stress echocardiography?

Cardiovascular morbidity and mortality rates are considered to be high in patients with diabetes despite negative stress test results; however, little data are available to support this supposition. We compared the long-term cardiovascular events between patients with diabetes and those without diabetes with negative treadmill stress echocardiography and evaluated the predictors for cardiovascular events in patients with diabetes. A total of 1,243 consecutive patients (mean age, 56 ± 10 years; non-diabetics: diabetics, 975:268; mean follow-up of 5 years) with negative treadmill stress echocardiography were evaluated. Clinical data were examined, and major adverse cardiovascular events (MACEs, a composite of coronary revascularization, acute myocardial infarction, and cardiovascular death) were compared between the non-diabetic and diabetic groups. In the population matched by clinical characteristics, the diabetic and non-diabetic groups had similar occurrence of MACEs (non-diabetics vs. diabetics = 5% versus 7%; p = 0.329) and event-free survival. MACEs in the diabetic group were associated with elevated early diastolic velocity of the mitral inflow/mitral annulus (E/e') ratio, indicative of diastolic dysfunction. The absence of statin and dipeptidyl peptidase-4 inhibitor use and use of sulfonylureas were also predictors of more MACEs. In conclusion, long-term cardiovascular events in patients with diabetes and negative stress echocardiography were comparable to those in patients without diabetes. However, appropriate monitoring of diastolic dysfunction, statin use, and individualized antidiabetic drug selection are required to reduce the cardiovascular risk in patients with diabetes.

What are the prognostic implications and factors relating to exercise induced electrocardiographic ST segment changes in the setting of a non-ischemic stress echocardiogram?

BACKGROUND

Electrocardiographic (ECG) changes during stress testing are a common and perplexing finding during non-ischemic stress echocardiography (niSE). Research has provided conflicting results regarding the implications.

METHODS

SE was performed after maximal Bruce protocol treadmill exercise.

RESULTS

3020 consecutive patients, mean age 58 ± 12 years, 36% female, were followed-up for up to 9 years (mean 36 ± 21 months) post niSE. Time to first cardiac event (composite of heart failure admission, worsening New York Heart Association class, worsening ejection fraction, acute coronary syndrome, revascularization, angina or cardiovascular death) was analysed and adjusted using Cox proportional hazards regression. Prognostic significance was found with 1.5 mm of downsloping or horizontal ST depression. Adjusting for baseline differences, increased risk of composite major adverse cardiac events was shown with at least 1.5 mm of exercise induced ST depression (Hazard ratio [HR] of 2.47, 95% Confidence ratio [CI] 1.67-3.72, p < 0.0001). Patients achieving high level exercise capacity (≥13 metabolic equivalents or METs) with ST depression lower risk of cardiac events during follow-up.

CONCLUSION

Patients with ST segment depression but non-ischemic stress imaging have a poorer prognosis compared to patients with niSE with normal stress ECGs. ST depression of 1.5 mm or more was established as a prognostically significance value. High exercise capacity was associated with an improved prognosis, and ECG changes in that setting can be regarded as false positives. All niSE have low risk of a cardiac event in the very short term (<12 months). Overall, ST depression during non-ischaemic stress imaging is not a benign finding.

Exercise Systolic Reserve and Exercise Pulmonary Hypertension Improve Diagnosis of Heart Failure With Preserved Ejection Fraction

Aims

Diastolic stress testing (DST) is recommended to confirm heart failure with preserved ejection fraction (HFpEF) in patients with exertional dyspnea, but current algorithms do not detect all patients. We aimed to identify additional echocardiographic markers of elevated pulmonary arterial wedge pressure during exercise (exPAWP) in patients referred for DST.

Methods and Results

We identified candidate parameters in 22 patients referred for exercise right heart catheterization with simultaneous echocardiography. Elevated exPAWP (≥25 mmHg) was present in 14 patients, and was best identified by peak septal systolic annular velocity <9.5 cm/s [exS', area under the receiver operating characteristic curve (AUC) 0.97, 95% confidence interval 0.92–1.0] and mean pulmonary artery pressure/cardiac output slope ≥3.2 mmHg/L [mPAP/CO, AUC 0.88 (0.72–1.0)]. We propose a decision tree to identify patients with elevated exPAWP. Applying this decision tree to 326 patients in an independent non-invasive DST cohort showed that patients labeled as “high probability of HFpEF” (n = 85) had reduced peak oxygen uptake [13.0 (10.7–15.1) mL/kg/min, p < 0.001 vs. intermediate/low probability], high H2FPEF score [53 (40–72) %, p < 0.001 vs. intermediate/low probability], and typical clinical characteristics. The diagnostic yield of DST increased from 11% using exercise E/e', to 62% using the decision tree.

Conclusion

In DST for suspected HFpEF, exS' was the most accurate echocardiographic parameter to identify elevated PAWP. We propose a decision tree including exS' and mPAP/CO for interpretation of DST. Application of this decision tree revealed typical HFpEF characteristics in patients labeled as high probability of HFpEF, and substantially reduced the number of inconclusive results.

Updated knowledge and practical implementations of stress echocardiography in ischemic and non-ischemic cardiac diseases: an expert consensus of the Working Group of Echocardiography of the Hellenic Society of Cardiology

Stress echocardiography (SE) is a well-established and valid technique, widely-used for the diagnostic evaluation of patients with ischemic and non-ischemic cardiac diseases. This statement of the Echocardiography Working Group of the Hellenic Society of Cardiology summarizes the consensus of the writing group regarding the applications of SE, based on the expertise of their members and on a critical review of current medical literature. The main objectives of the consensus document include a comprehensive review of SE methodology and training, focusing on the preparation, the protocols used and the analysis of the SE images and an updated, evidence-based knowledge about SE applications on ischemic and non-ischemic heart diseases, such as in cardiomyopathies, heart failure and valvular heart disease.

Prognostic Value of Diastolic Dysfunction Derived From D-SPECT in Coronary Artery Disease Patients With Normal Ejection Fraction

Diastolic dysfunction (DD) with normal systolic function has been elucidated to be associated with heart failure and worse prognosis. The recently introduced single photon emission computed tomography (SPECT) with dedicated cardiac cadmium-zinc-telluride (CZT) cameras (D-SPECT) is a novel method to quantitate left ventricular functional parameters. We aimed to evaluate the prognostic value of DD derived from D-SPECT in coronary artery disease (CAD) patients with normal ejection fraction. All CAD patients who underwent D-SPECT and invasive coronary angiography within 3 months were considered. DD was defined as peak filling rate (PFR) <2.1 end diastolic volume (EDV, ml)/s according to the D-SPECT results. Patients were divided into three groups: group 1 (n = 226)-normal PFR; group 2 (n = 67)-ischemia-related DD (abnormal stress PFR and normal rest PFR); and group 3 (n = 106)-rest DD (abnormal rest PFR). The primary clinical endpoint of the present study was a composite of heart failure events (HFE). A total of 399 consecutive CAD patients with normal systolic function undergoing stress D-SPECT were analyzed. The incidence rates of HFE among the three groups were 4.0, 7.5, and 11.3%, respectively. Cox regression analysis showed that the multivariate predictors of HFE were rest PFR, diabetes mellitus, obesity, and old age. DD derived from D-SPECT in CAD patients with normal ejection fraction is predictive of HFE.

Clinical relevance of spectral tissue Doppler-derived E/e' in older patients with preserved ejection fraction

BACKGROUND

The E/e' index measured in spectral tissue Doppler is included in the recommendations for the diagnosis by transthoracic Doppler echocardiography of left ventricular diastolic dysfunction and heart failure with preserved ejection fraction. While E/e' is influenced by age in healthy individuals, no studies have evaluated this index in elderly patients. This study addressed the clinical relevance of E/e' in assessment of left ventricular diastolic function in elderly patients with preserved ejection fraction and its relevance from both a diagnostic and prognostic perspective based on the existing literature.

METHODS

A total of 76 patients≥70years of age were prospectively included. The analysis of left ventricular diastolic function was adapted from the 2016 ASE/EACVI recommendations without consideration of E/e'.

RESULTS

The mean age was 85years. In all, 42 patients had moderate-to-severe diastolic dysfunction (elevated left atrial pressure). Mean E/e' was significantly correlated with diastolic function (r=0.58, P<0.001). Mean E/e'>13.3 had a sensitivity of 86% and a specificity of 91% in the diagnosis of moderate-to-severe diastolic dysfunction (AUC: 0.92). E/(e'xs') (AUC: 0.89) and NT pro-BNP (AUC: 0.80) did not perform better than E/e'. The existing literature offers large body of evidence that E/e' provides essential diagnostic and prognostic information in older patients with cardiovascular disease.

CONCLUSION

E/e' is accurate in the diagnosis of significant diastolic dysfunction, in the diagnosis of heart failure with preserved ejection fraction and in risk stratification in older patients with cardiovascular disease.

The prognostic value of estimating stroke volume before and after exercise during treadmill stress echocardiography

BACKGROUND

Stress echocardiography (SE) is an established technique for assessment of coronary artery disease (CAD) which is difficult to perform and interpret. Left ventricular stroke volume (SV) is readily estimated with Doppler echocardiography. It can be affected by myocardial ischemia, with possible adjunctive value during SE.

METHODS

Patients underwent Bruce protocol SE with SV estimated before and after maximal treadmill exertion post routine regional wall analysis. Incremental change in SV (ΔSV) with exercise was measured.

RESULTS

A derivation cohort (n = 273) was established to test the hypothesis. An optimal cutoff for detection on inducible ischemia was ΔSV ≤ +10 mL. The validation cohort of consecutive patients (n = 1093, 376 [34%] female; age 59 ± 12 years) were followed clinically after SE for 20 460 patient-months. There were 1000 patients with nonischemic SE, and 93 patients with studies suggestive of myocardial ischemia. Secondary analysis yielded 831 patients with a normal exercise response (ΔSV > +10 mL) and 192 with an abnormal ΔSV ≤ +10 mL. Time to first combined adverse cardiac event (composite of angina, acute coronary syndrome, cardiac revascularization, worsening New York Heart Association (NYHA) class, a reduction in EF, and cardiovascular death) was analyzed and adjusted using Cox proportional hazards regression. The hazard ratio for an adverse event with an abnormal ΔSV response (≤10 mL) was 10.3 (95% confidence intervals 5.6-19.1, P < .0001).

CONCLUSIONS

Stroke volume assessment during SE is feasible and readily performed. It is simple, practical, and has incremental diagnostic and prognostic value when added to exercise regional wall-motion analysis.

Prognostic significance of exercise-induced diastolic dysfunction: A systematic review

BACKGROUND

Recent guidelines recommend diastolic stress testing among patients with unexplained dyspnea. Previous studies have reported exercise related change in diastolic parameters as a prognostic marker for worse outcomes. However, the role of exercise-induced diastolic dysfunction (DD) in predicting adverse outcomes has not been fully established.

METHOD

We conducted a meta-analysis to explore the prognostic significance of exercise-induced DD. PUBMED/EMBASE/SCOPUS databases were searched for studies reporting adverse outcomes in patients undergoing exercise echocardiography based on diastolic response during exercise. Exercise-induced DD was defined as an increase in E/e' or E/A ratio with stress. Outcomes of interest were cardiovascular mortality or hospitalizations.

RESULTS

A total of 8 studies were identified, including 4,462 patients who underwent exercise stress echocardiography. The follow-up ranged from 13 months to 5 years. The major indication for stress testing was exertional dyspnea. All studies reported cardiac mortality and hospitalization in the composite outcome. Meta-analysis conducted using random-effects model showed that exercise-induced DD was associated with a higher likelihood of cardiovascular mortality or hospitalization (HR = 1.32, P < .05). Significant heterogeneity was noted among the studies.

CONCLUSIONS

Exercise-induced DD is associated with worse cardiovascular outcomes. Changes in echocardiographic parameters such as e' with exercise might be useful for risk stratification and identification of high-risk patients.

Impaired Exercise Tolerance in Heart Failure With Preserved Ejection Fraction: Quantification of Multiorgan System Reserve Capacity

Exercise intolerance is a principal feature of heart failure with preserved ejection fraction (HFpEF), whether or not there is evidence of congestion at rest. The degree of functional limitation observed in HFpEF is comparable to patients with advanced heart failure and reduced ejection fraction. Exercise intolerance in HFpEF is characterized by impairments in the physiological reserve capacity of multiple organ systems, but the relative cardiac and extracardiac deficits vary among individuals. Detailed measurements made during exercise are necessary to identify and rank-order the multiorgan system limitations in reserve capacity that culminate in exertional intolerance in a given person. We use a case-based approach to comprehensively review mechanisms of exercise intolerance and optimal approaches to evaluate exercise capacity in HFpEF. We also summarize recent and ongoing trials of novel devices, drugs, and behavioral interventions that aim to improve specific exercise measures such as peak oxygen uptake, 6-min walk distance, heart rate, and hemodynamic profiles in HFpEF. Evaluation during the clinically relevant physiological perturbation of exercise holds promise to improve the precision with which HFpEF is defined and therapeutically targeted.

Arterial-Ventricular Coupling Evaluation in Individuals with Stress-Evidenced Diastolic Dysfunction: A Pilot Study. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2020;2020:2598-2601. [PMID: 33018538 DOI: 10.1109/embc44109.2020.9176106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

INTRODUCTION

Arterial-ventricular coupling (AVC) has been recognized as a key determinant of global cardiovascular performance. Diastolic dysfunction (DD) occurs when inadequate filling of the ventricles is related to an abnormal elevation of intracardiac filling pressures. In some cases, DD is evidenced during cardiac stress, provoked by exercise.

OBJECTIVE

To evaluate AVC in individuals with stress evidenced DD, in relation to controls.

MATERIALS AND METHODS

Stress echocardiography was applied to assess cardiac function during exercise. Arterial-ventricular coupling was evaluated, based on the assessment of left ventricular and arterial elastances.

RESULTS

AVC showed a significant difference at peak exercise compared to controls, basically due to a loss of cardiac contractility.

CONCLUSION

The manifestation of AVC coupling imbalance could act as a complementary parameter to support the diagnosis of DD.