The Clinical Use of Stress Echocardiography in Non-Ischaemic Heart Disease: Recommendations from the European Association of Cardiovascular Imaging and the American Society of Echocardiography

Stress Echocardiography for Assessment of Diastolic Function

PURPOSE OF REVIEW

Diastolic dysfunction is an important, though often underappreciated, cause for exertional dyspnea. Echocardiography enables noninvasive evaluation of diastolic function and filling pressure, but images acquired at rest may be insensitive for detection of exertional abnormalities. This review focuses on stress echocardiography to assess diastolic function, including traditional and novel techniques, with emphasis on specific patient sub-groups in whom this testing may be valuable.

RECENT FINDINGS

Emerging data informs patient selection for diastolic stress testing. Further, increasing literature provides considerations for performance and interpretation of diastolic metrics relevant to patients with heart failure with preserved ejection fraction, hypertrophic cardiomyopathy, athletes, and those with microvascular coronary dysfunction. Methods, such as speckle-tracking and multi-modality imaging, provide additional and complementary information for non-invasive diastolic assessment. This review serves as a guide to optimally utilize existing and novel techniques of stress echocardiography for diastolic assessment across a broad range of patients.

Randomised study for the Optimal Treatment of symptomatic patients with low-gradient severe Aortic valve Stenosis and preserved left ventricular ejection fraction (ROTAS trial)

BACKGROUND

The best management of symptomatic patients with low-gradient (LG) severe aortic stenosis (AS) and preserved left ventricular ejection fraction (LVEF) has not been established. The Randomised study for the Optimal Treatment of symptomatic patients with low-gradient severe Aortic valve Stenosis (ROTAS) trial aimed to assess the superiority of aortic valve replacement (AVR) versus medical treatment (MT) in this specific group of AS patients.

METHODS

Patients with symptomatic LG severe AS and preserved LVEF (>50%) underwent dobutamine stress echocardiography and/or CT-aortic calcium score to confirm AS severity and were then randomised 1:1 to AVR or MT. The primary endpoint was a composite of overall death and/or cardiovascular hospitalisation.

RESULTS

The ROTAS study was stopped early because of insufficient recruitment. In the end, only 52 patients (age 79±7 years; women 54%; NYHA III-IV 27%; median STS score 3.3%) were included in the study. During follow-up (mean: 14±7 months), the primary endpoint occurred in 12 (23%) patients. Compared with MT, AVR was not associated with a significant prognostic benefit (events: 5/26 (19%) vs 7/26 (27%) (HR 0.76, 95% CI 0.24 to 2.39, p=0.63). During follow-up, 11 (42%) patients in the MT group developed class I criteria for AVR or severe symptoms justifying a cross-over to the AVR group.

CONCLUSIONS

Because of the small number of included patients and short follow-up the ROTAS trial was underpowered and unable to demonstrate a difference in the study endpoint between treatment arms. In patients in the MT arm, a regular echocardiographic and clinical assessment might be useful to disclose those developing class I indications of AVR or severe AS-related symptoms.

TRIAL REGISTRATION NUMBER

NCT01835028.

Stress Echocardiography in the Follow-Up of Young Patients with Repaired Aortic Coarctation

Background: Aortic coarctation (CoA) is a congenital heart disease affecting 5-8% of patients, with long-term complications persisting despite successful correction. Stress echocardiography (SE) is increasingly used for evaluating cardiac function under stress, yet its role in repaired CoA remains under-explored. Objective: This study aimed to assess the predictive value of SE and myocardial strain in repaired CoA patients with a history of hypertension without significant gradients or with borderline gradients at rest. Methods: Between June 2020 and March 2024, we enrolled 35 consecutive CoA patients with successful repairs and either a history of hypertension or borderline Doppler gradients. Baseline and peak exercise echocardiographic measurements, including left ventricular mass index (LVMi) and global longitudinal strain (LVGLS), were recorded. Patients were followed for up to 4 years. Results: At baseline, the positive SE group had higher systolic blood pressure (SBP) and diastolic blood pressure (DBP) compared to the negative SE group. The positive SE group also exhibited significantly higher basal and peak trans-isthmic gradients. Positive SE was found in 45.7% of patients, with 68.7% of these requiring re-intervention during follow-up. A peak trans-isthmic gradient > 61 mmHg during exercise predicted recoarctation with 100% sensitivity and 71% specificity (AUC = 0.836, p < 0.004). Conclusions: SE identifies at-risk patients post-CoA repair, aiding in early intervention. A peak trans-isthmic gradient > 61 mmHg during exercise is a strong predictor of recoarctation. These findings support incorporating SE into routine follow-up protocols for CoA patients, particularly those with a history of hypertension and borderline gradients, to improve long-term outcomes and quality of life.

Interpreting Diastolic Dynamics and Evaluation through Echocardiography

In patients with heart failure, evaluating left ventricular (LV) diastolic function is vital, offering crucial insights into hemodynamic impact and prognostic accuracy. Echocardiography remains the primary imaging modality for diastolic function assessment, and using it effectively requires a profound understanding of the underlying pathology. This review covers four main topics: first, the fundamental driving forces behind each phase of normal diastolic dynamics, along with the physiological basis of two widely used echocardiographic assessment parameters, E/e' and mitral annulus early diastolic velocity (e'); second, the intricate functional relationship between the left atrium and LV in patients with varying degrees of LV diastolic dysfunction (LVDD); third, the role of stress echocardiography in diagnosing LVDD and the significance of echocardiographic parameter changes; and fourth, the clinical utility of evaluating diastolic function from echocardiography images across diverse cardiovascular care areas.

Stress echocardiography in heart failure patients: additive value and caveats

Heart failure (HF) is a clinical syndrome characterized by well-defined signs and symptoms due to structural and/or myocardial functional impairment, resulting in raised intracardiac pressures and/or inadequate cardiac stroke volume at rest or during exercise. This could derive from direct ischemic myocardial injury or other chronic pathological conditions, including valvular heart disease (VHD) and primary myocardial disease. Early identification of HF etiology is essential for accurate diagnosis and initiation of early and appropriate treatment. Thus, the presence of accurate means for early diagnosis of HF symptoms or subclinical phases is fundamental, among which echocardiography being the first line diagnostic investigation. Echocardiography could be performed at rest, to identify overt structural and functional abnormalities or during physical or pharmacological stress, in order to elicit subclinical myocardial function impairment e.g. wall motion abnormalities and raised ventricular filling pressures. Beyond diagnosis of ischemic heart disease, stress echocardiography (SE) has recently shown its unique value for the evaluation of diastolic heart failure, VHD, non-ischemic cardiomyopathies and pulmonary hypertension, with recommendations from international societies in several clinical settings. All these features make SE an important additional tool, not only for diagnostic assessment, but also for prognostic stratification and therapeutic management of patients with HF. In this review, the unique value of SE in the evaluation of HF patients will be described, with the objective to provide an overview of the validated methods for each setting, particularly for HF management.

Usefulness of exercise stress echocardiography for predicting cardiovascular events and atrial fibrillation in hypertrophic cardiomyopathy

BACKGROUND

In hypertrophic cardiomyopathy (HCM), the determinants of exercise tolerance and the usefulness of exercise stress echocardiography (ESE) for predicting hard endpoints have not been fully investigated. We aimed to assess the key parameters of ESE for exercise tolerance and the factors predictive of cardiovascular events and new-onset atrial fibrillation (AF) in patients with HCM.

METHODS

Seventy-four consecutive patients with HCM who underwent ESE and with an ejection fraction ≥50 % were enrolled. The primary endpoint was a composite of cardiovascular death, heart failure hospitalization, ventricular fibrillation or tachycardia, and ventricular assist device implantation. The secondary endpoint was new-onset AF.

RESULTS

The primary endpoint occurred in 13 patients. The left and right ventricular functions during exercise were responsible for decreased exercise tolerance. Peak exercise e' and tricuspid annular plane systolic excursion (TAPSE) significantly predicted increased primary outcome risk (hazard ratio 1.35, 95 % confidence interval 1.10-1.76, p = 0.003; hazard ratio 1.19, 95 % confidence interval 1.07-1.32, p = 0.002, respectively), and the results were consistent even after adjustment by maximum workload. These ESE parameters improved the prognostic model containing estimated glomerular filtration rate (eGFR) and left atrial (LA) volume index. In AF-naive patients (n = 58), LA volume, peak exercise LA reservoir strain, and left ventricular outflow tract (LVOT) pressure gradient predicted new-onset AF.

CONCLUSIONS

In patients with HCM, ESE parameters related to left and right ventricular function were responsible for low exercise tolerance. Furthermore, e' and TAPSE at peak workload could be useful for predicting cardiovascular events in addition to eGFR and LA volume index. LVOT pressure gradient and LA function during exercise predicted new-onset AF.

Dobutamine Stress Echocardiography in Low-Gradient Aortic Stenosis

IMPORTANCE

Guidelines recommend the use of dobutamine stress echocardiography (DSE) in patients with low-gradient aortic stenosis (AS) and left ventricular ejection fraction (LVEF) <50%. However, a paucity of DSE data exists when LVEF >35%.

OBJECTIVE

To examine the diagnostic accuracy of DSE in patients with low-gradient AS with a wide range of LVEF and to examine the interaction between the diagnostic accuracy of DSE and LVEF.

DESIGN, SETTING, AND PARTICIPANTS

Patients with mean gradient <40 mm Hg, aortic valve area <1.0 cm2, and stroke volume index ≤35 mL/m2 undergoing DSE and cardiac computer tomography (C-CT) were identified from 3 prospectively collected patient cohorts and stratified according to LVEF: LVEF<35%, LVEF 35% to 50%, and LVEF>50%.

EXPOSURE

Dobutamine stress echocardiography and C-CT were performed on patients with low-gradient AS.

MAIN OUTCOMES AND MEASURES

Severe AS was defined as aortic valve calcification score ≥2,000 arbitrary units (AU) among men and ≥1,200 AU for women on C-CT.

RESULTS

Of 221 patients included in the study, 78 (35%) presented with LVEF <35%, 67 (30%) with LVEF 35% to 50%, and 76 (34%) with LVEF >50%. Mean-gradient and aortic valve peak velocity during DSE showed significant diagnostic heterogeneity between LVEF groups, being most precise when LVEF <35% (both areas under the curve [AUC] = 0.90), albeit with optimal thresholds of 30 mm Hg and 377 cm/sec and a limited diagnostic yield in patients with LVEF ≥35% (AUC = 0.67 and 0.66 in LVEF 35% to 50% and AUC = 0.65 and 0.60 in LVEF ≥50%). Using guideline thresholds led to a sensitivity/specificity of 49%/84% for all patients with LVEF <50%.

CONCLUSION AND RELEVANCE

While DSE is safe and leads to an increase in stroke volume in patients with low-gradient AS regardless of LVEF, the association between DSE gradients and AS severity assessed by C-CT demonstrates important heterogeneity depending on LVEF, with the highest accuracy in patients with LVEF <35%.

Prognostic value of exercise longitudinal right ventricular free wall strain in patients with sickle cell disease

Longitudinal right ventricular free wall strain (RVFWS) has been identified as an independent prognostic marker in patients with pulmonary hypertension. Little is known however about the prognostic value of RVFWS in patients with sickle cell (SC) disease, particularly during exercise. We therefore examined the prognostic significance of RVFWS both at rest and with exercise in patients with SC disease and normal resting systolic pulmonary artery pressure (SPAP). Consecutive patients with SC disease referred for bicycle ergometer stress echocardiography (SE) were enrolled ftom July 2019 to January 2021. All patients had measurable tricuspid regurgitation velocity (TRV). Conventional echocardiography parameters, left ventricular global longitudinal strain (LVGLS), RVFWS, and ventriculoarterial coupling indices (TAPSE/SPAP and RVFWS/SPAP) were assessed at rest and peak exercise. Repeat SE was performed at a median follow-up of 2 years. The cohort consisted of 87 patients (mean age was 31 ± 11 years, 66% females). All patients had normal resting TRV < 2.8 m/s, RVFWS and LVGLS at baseline. There were 23 (26%) patients who had peak stress RVFWS < 20%. They had higher resting and peak stress TRV and SPAP, but lower resting and peak stress TAPSE/SPAP, RVFWS/SPAP, and LVGLS as well as lower peak stress cardiac output when compared to patients with peak stress RVFWS ≥ 20% (p < 0.05). Patients with baseline peak stress RVFWS < 20% had a significant decrease in exercise performance at follow-up (7.5 ± 2.7 min at baseline vs. 5.5 ± 2.8 min at follow-up, p < 0.001). In the multivariate analysis, baseline peak stress RVFWS was the only independent predictor of poorer exercise performance at follow-up [odds ratio 8.2 (1.2, 56.0), p = 0.033]. Among patients with SC disease who underwent bicycle ergometer SE, a decreased baseline value of RVFWS at peak stress predicted poorer exercise time at follow-up.

The roles of exercise stress echocardiography for the evaluation of heart failure with preserved ejection fraction in the heart failure pandemic era

Heart failure with preserved ejection fraction (HFpEF) accounts for nearly 70% of all HF and has become the dominant form of HF. The increased prevalence of HFpEF has contributed to a rise in the number of HF patients, known as the "heart failure pandemic". In addition to the fact that HF is a progressive disease and a delayed diagnosis may worsen clinical outcomes, the emergence of disease-modifying treatments such as sodium-glucose transporter 2 inhibitors and glucagon-like peptide-1 receptor agonists has made appropriate and timely identification of HFpEF even more important. However, diagnosis of HFpEF remains challenging in patients with a lower degree of congestion. In addition to normal EF, this is related to the fact that left ventricular (LV) filling pressures are often normal at rest but become abnormal during exercise. Exercise stress echocardiography can identify such exercise-induced elevations in LV filling pressures and facilitate the diagnosis of HFpEF. Exercise stress echocardiography may also be useful for risk stratification and assessment of exercise tolerance as well as cardiovascular responses to exercise. Recent attention has focused on dedicated dyspnea clinics to identify early HFpEF among patients with unexplained dyspnea and to investigate the causes of dyspnea. This review discusses the role of exercise stress echocardiography in the diagnosis and evaluation of HFpEF.

Mixed-type Dyspnoea Diagnosed via Non-invasive and Invasive Cardiopulmonary Exercise Tests

A gas exchange analysis with the cardiopulmonary exercise test is effective in discriminating non-cardiogenic components of limited exercise tolerance and is important for use in combination with the diastolic stress test. An 80-year-old woman with progressive exertional dyspnoea, hypertension, and untreated bronchial asthma was diagnosed with heart failure with a preserved ejection fraction by invasive testing. Diuretics were initiated, which resulted in partial symptom improvement. A subsequent non-invasive test revealed a reduced breathing reserve, suggesting exertional dyspnoea complications linked to lung disease. Bronchodilators were administered, which further improved the symptoms.

Impact of Stress Echocardiography on Aortic Valve Stenosis Management

Rest and stress echocardiography (SE) play a fundamental role in the evaluation of aortic valve stenosis (AS). According to the current guidelines for the echocardiographic evaluation of patients with aortic stenosis, four broad categories can be defined: high-gradient AS (mean gradient ≥ 40 mmHg, peak velocity ≥ 4 m/s, aortic valve area (AVA) ≤ 1 cm2 or indexed AVA ≤ 0.6 cm2/m2); low-flow, low-gradient AS with reduced ejection fraction (mean gradient < 40 mmHg, AVA ≤ 1 cm2, left ventricle ejection fraction (LVEF) < 50%, stroke volume index (Svi) ≤ 35 mL/m2); low-flow, low-gradient AS with preserved ejection fraction (mean gradient < 40 mmHg, AVA ≤ 1 cm2, LVEF ≥ 50%, SVi ≤ 35 mL/m2); and normal-flow, low-gradient AS with preserved ejection fraction (mean gradient < 40 mmHg, AVA ≤ 1 cm2, indexed AVA ≤ 0.6 cm2/m2, LVEF ≥ 50%, SVi > 35 mL/m2). Aortic valve replacement (AVR) is indicated with the onset of symptoms development or LVEF reduction. However, there is often mismatch between resting transthoracic echocardiography findings and patient's symptoms. In these discordant cases, SE and CT calcium scoring are among the indicated methods to guide the management decision making. Additionally, due to the increasing evidence that in asymptomatic severe aortic stenosis an early AVR instead of conservative treatment is associated with better outcomes, SE can help identify those that would benefit from an early AVR by revealing markers of poor prognosis. Low-flow, low-gradient AS represents a challenge both in diagnosis and in therapeutic management. Low-dose dobutamine SE is the recommended method to distinguish true-severe from pseudo-severe stenosis and assess the existence of flow (contractile) reserve to appropriately guide the need for intervention in these patients.

Cirrhotic cardiomyopathy: a subject that's always topical

Cirrhosis is the final stage in the development of hepatic fibrosis in chronic liver disease. It is associated with major hemodynamic disturbances defining the hyperdynamic circulation and may be complicated by specific cardiac involvement or cirrhotic cardiomyopathy which is a silent clinical condition that typically remains asymptomatic until the late stages of liver disease. Recently, new criteria defining CC, based on modern concepts and knowledge of heart failure, have been proposed. Despite knowledge of the main mechanisms behind this entity, there is no specific treatment available for cirrhotic cardiomyopathy. The management approach for symptomatic cardiomyopathy in cirrhotic patients is similar to that for left ventricular failure in non-cirrhotic individuals.

Percutaneous intramyocardial septal radiofrequency ablation after 5-year follow-up

OBJECTIVE

The objective is to evaluate the 5-year follow-up results of percutaneous intramyocardial septal radiofrequency ablation (PIMSRA) for hypertrophic obstructive cardiomyopathy (HOCM), including clinical status, electrocardiographic and echocardiographic characteristics.

METHODS

27 patients (age: 44.3±15.5 years; 67% men, 33% women) with severely symptomatic HOCM who underwent PIMSRA from October 2016 to September 2017 were included. Their clinical status, resting and exercise stress echocardiography, electrocardiography and cardiac MRI (CMRI) after long-term follow-up were assessed.

RESULTS

One patient died of intracerebral haemorrhage 1 year post procedurally. The New York Heart Association class, Canadian Cardiovascular Society class and exercise-induced syncopal attacks improved significantly in 26 patients (all p<0.01). Left ventricular (LV) outflow tract gradients revealed sustained reduction (resting: from 95.0 to 9.0 mm Hg, p<0.001; post exercise: from 130.5 to 21.0 mm Hg, p<0.001). The echocardiographic evaluation revealed decreased septal thickness, LV posterior wall thickness and left atrial (LA) diameter (all p<0.001). CMRI data revealed decrease in LV mass index and LA volume index and increase in LV end-diastolic volume index and stroke volume index between baseline and long-term follow-up (all p<0.05). The global longitudinal strain of LV improved from (-11.9%±3.7%) before the procedure to (-13.1%±3.9%) at the last check (p<0.001). Malignant ventricular arrhythmia and heart failure events were not observed.

CONCLUSIONS

PIMSRA can effectively alleviate symptoms in patients with HOCM and improve their hemodynamics in the long term.

TRIAL REGISTRATION NUMBER

NCT02888132.

An Increase in the Left Atrium Volume During Exercise is Associated With a Positive Result of a Diastolic Stress Test in Patients With Arterial Hypertension

AIM

To study the relationship between changes in left atrial volume (LAV) during exercise and the result of a diastolic stress test (DST) in patients with arterial hypertension (AH).

MATERIAL AND METHODS

The study included 219 patients with AH without ischemic heart disease and atrial fibrillation. During the DST performed before and after exercise, the ratio of transmitral flow velocity to mitral annular velocity (E/e'), the left atrial global longitudinal strain in the reservoir phase (reservoir strain), and LAV were determined. The criterion for a positive DST was an increase in E/e' ≥15.

RESULTS

A positive result of DST was observed in 90 (41.1%) patients. Patients with positive DST were older (65.0 and 59.0 years); among them, there were fewer men (24.4 and 41.1%), but more patients with obesity (66.7 and 40.3%) and diabetes mellitus (36.7 and 8.5%). At rest, patients with positive DST had higher E/e' ratio (11.5 and 8.8), pulmonary artery systolic pressure (29.0 and 27.0 mm Hg), and LAV (60.0 and 52.0 ml), but a lower left atrial reservoir strain (20.0 and 24.0%). During exercise in patients with positive and negative DST, E/e' increased by 5.46 and 0.47 units, respectively. Changes in the LAV and reservoir strain during exercise in these groups were directed differently. In patients with positive DST, the left atrial reservoir strain decreased by 1.0 percentage points (pp) whereas in patients with negative DST, it increased by 8.0 pp. During exercise, the LAV increased by 10.0 ml in patients with a positive DST, whereas in the alternative group, the LAV decreased by 8.5 ml. The AUC for changes in LAV as an indicator of a positive DST was 0.987 while the AUC for the resting left atrial reservoir strain was 0.938. An increase in LAV >1 ml, as an indicator of a positive DST has a sensitivity of 96.9% and a specificity of 95.1%.

CONCLUSION

In AH patients, changes in left ventricular filling pressure are associated with a unidirectional change in LAV. An increase in LAV during exercise by more than 1 ml can serve as a criterion for a positive DST result. This assessment was consistent with the assessment of the DST result by the E/e' criterion >15 in 94.5% of cases.

2023 Multimodality Appropriate Use Criteria for the Detection and Risk Assessment of Chronic Coronary Disease: A Summary for JASE

This report provides a descriptive summary of the ACC/AHA/ASE/ASNC/ASPC/HFSA/HRS/SCAI/SCCT/SCMR/STS 2023 Multimodality Appropriate Use Criteria for the Detection and Risk Assessment of Chronic Coronary Disease with an emphasis on the role of stress echocardiography.

Pathophysiologic and prognostic importance of cardiac power output reserve in heart failure with preserved ejection fraction

AIMS

Heart failure with preserved ejection fraction (HFpEF) is a syndrome characterized by multiple cardiac reserve limitations during exercise. Cardiac power output (CPO) is an index of global cardiac performance and can be estimated non-invasively by echocardiography. We hypothesized that CPO reserve during exercise would be associated with impaired cardiovascular reserve, exercise intolerance, and adverse outcomes in HFpEF.

METHODS AND RESULTS

Exercise stress echocardiography was performed in 425 dyspnoeic patients [217 HFpEF and 208 non-heart failure (HF) controls] to estimate CPO at rest and during exercise. We classified patients with HFpEF based on the median value of changes in CPO from rest to peak exercise (ΔCPO >0.49 W/100 g). Patients with HFpEF and a lower CPO reserve had poorer biventricular systolic function, impaired chronotropic response during exercise, and worse aerobic capacity than controls and those with a higher CPO reserve. During a median follow-up of 358 days, a composite outcome of all-cause mortality or HF events occurred in 30 patients. Patients with a lower CPO reserve had four-fold and nearly 10-fold increased risks of the outcomes compared with those with a higher CPO reserve and controls, respectively [hazard ratio (HR) 4.05, 95% confidence interval (CI) 1.16-10.1, P = 0.003 and HR 9.61, 95% CI 3.58-25.8, P < 0.0001]. We further found that a lower CPO reserve had an incremental prognostic value over the H2FPEF score and exercise duration. In contrast, resting CPO did not predict clinical outcomes in patients with HFpEF.

CONCLUSION

A lower CPO reserve was associated with biventricular systolic dysfunction, chronotropic incompetence, exercise intolerance, and adverse outcomes in patients with HFpEF.

Prognostic value of transvalvular flow rate in patients with low-gradient severe aortic stenosis: A dobutamine stress echocardiography study

BACKGROUNDS

There are limited data on the clinical relevance of transvalvular flow rate (Qmean ) at rest (Qrest) and at peak stress (Qstress ) during dobutamine stress echocardiography (DSE) in patients with low-gradient severe aortic stenosis (LG-SAS).

METHODS

We retrospectively analyzed the clinical data of patients with LG-SAS who underwent DSE. LG-SAS was defined as an aortic valve (AV) area index of < .6 cm2 /m2 and a mean AV pressure gradient (AVPG) of < 40 mm Hg. The primary endpoint included all-cause death and heart failure hospitalization.

RESULTS

Of 100 patients (mean age 79.5 ± 7.3 years; men, 45.0%; resting left ventricular ejection fraction [LVEF] 52.1% ± 15.9%; resting stroke volume index 35.8 ± 7.7 mL/m2 ; Qrest 171.8 ± 34.9 mL/s), the primary endpoint occurred in 51 patients during a median follow-up of 2.84 (interquartile range 1.01-5.21) years. When the study patients were divided into three subgroups based on Qrest and Qstress , the multivariate analysis showed that Qrest < 200 mL/s and Qstress ≥200 mL/s (hazard ratio 3.844; 95% confidence interval 1.143-12.930; p = .030), as well as Qrest and Qstress < 200 mL/s (hazard ratio 9.444; 95% confidence interval 2.420-36.850; p = .001), were significantly associated with unfavorable outcomes with Qrest and Qstress ≥200 mL/s as a reference after adjusting for resting LVEF, resting mean AVPG, chronic kidney disease, New York Heart Association functional class III/IV, and AV replacement.

CONCLUSIONS

Flow conditions based on the combination of Qrest and Qstress are helpful for risk stratification in LG-SAS patients.

Guidelines for the Evaluation of Prosthetic Valve Function With Cardiovascular Imaging: A Report From the American Society of Echocardiography Developed in Collaboration With the Society for Cardiovascular Magnetic Resonance and the Society of Cardiovascular Computed Tomography

In patients with significant cardiac valvular disease, intervention with either valve repair or valve replacement may be inevitable. Although valve repair is frequently performed, especially for mitral and tricuspid regurgitation, valve replacement remains common, particularly in adults. Diagnostic methods are often needed to assess the function of the prosthesis. Echocardiography is the first-line method for noninvasive evaluation of prosthetic valve function. The transthoracic approach is complemented with two-dimensional and three-dimensional transesophageal echocardiography for further refinement of valve morphology and function when needed. More recently, advances in computed tomography and cardiac magnetic resonance have enhanced their roles in evaluating valvular heart disease. This document offers a review of the echocardiographic techniques used and provides recommendations and general guidelines for evaluation of prosthetic valve function on the basis of the scientific literature and consensus of a panel of experts. This guideline discusses the role of advanced imaging with transesophageal echocardiography, cardiac computed tomography, and cardiac magnetic resonance in evaluating prosthetic valve structure, function, and regurgitation. It replaces the 2009 American Society of Echocardiography guideline on prosthetic valves and complements the 2019 guideline on the evaluation of valvular regurgitation after percutaneous valve repair or replacement.

Comprehensive diagnostic workup in patients with suspected heart failure and preserved ejection fraction

Diagnosis of heart failure with preserved ejection fraction (HFpEF) can be challenging and it could require different tests, some of which are affected by limited availability. Nowadays, considering that new therapies are available for HFpEF and related conditions, a prompt and correct diagnosis is relevant. However, the diagnostic role of biomarker level, imaging tools, score-based algorithms and invasive evaluation, should be based on the strengths and weaknesses of each test. The aim of this review is to help the clinician in diagnosing HFpEF, overcoming the diagnostic uncertainty and disentangling among the different underlying causes, in order to properly treat this kind of patient.

Variability in approach to exercise stress echocardiography for diagnosis of heart failure with preserved ejection fraction: an international survey on real-world practice

Aims

The diagnosis of heart failure with preserved ejection fraction (HFpEF) remains challenging based on resting assessments. Exercise echocardiography is often used to unmask abnormalities that develop during exercise, but the diagnostic criteria have not been standardized. This study aimed to elucidate how cardiologists utilize exercise echocardiography to diagnose HFpEF in real-world practice.

Methods and results

An international web-based survey involving 87 cardiologists was performed. We also performed a retrospective cross-sectional study to investigate the impact of different exercise echocardiographic diagnostic criteria in 652 dyspnoeic patients who underwent exercise echocardiography. The HFA-PEFF algorithm was the most commonly used exercise echocardiography criterion for HFpEF diagnoses (48%), followed by the ASE/EACVI criteria (24%) and other combinations of multiple parameters (22%). Among 652 patients, the proportion of HFpEF diagnosis varied substantially according to the criteria used ranging from 20.1% (ASE/EACVI criteria) to 44.3% (HFA-PEFF algorithm). Many cases (49.4-70.5%) remained indeterminate after exercise echocardiography, but only 41% of surveyed cardiologists would utilize exercise right heart catheterization to resolve an indeterminate result. Despite these diagnostic uncertainties, 54% of surveyed cardiologists would utilize exercise echocardiography results to initiate sodium-glucose co-transporter 2 inhibitors.

Conclusion

In real-world practice, exercise echocardiographic criteria utilized across cardiologists vary, which meaningfully impacts the frequency of HFpEF diagnoses, with indeterminate results being common. Despite these diagnostic uncertainties, many cardiologists initiate pharmacotherapy based on exercise echocardiography. The lack of consensus on universal diagnostic criteria for exercise echocardiography and approaches to indeterminate results may limit the delivery of evidence-based treatment for HFpEF.

Stress echocardiography in valvular heart disease

Valvular heart disease (VHD) has been a significant health problem, particularly in developed countries, in relation to the aging population. Recent developments in the management of VHD require a more accurate assessment of disease severity to determine the need for transcatheter interventions or open heart surgery. Stress echocardiography is a crucial imaging modality for identifying the underlying pathology of VHD. Optimal administration of exercise or intravenous drugs may reveal hemodynamic abnormalities under stress without posing an invasive risk. Therefore, the implementation of stress echocardiography is recommended for determining interventional indications and risk stratification in mitral regurgitation and aortic stenosis. In addition, recent evidence has accumulated regarding the usefulness of stress echocardiography in various conditions including mitral stenosis, aortic regurgitation, and post-interventional VHD. Here, we summarize the current evidence and future perspectives on stress echocardiography in VHD.

American Society of Echocardiography COVID-19 Statement Update: Lessons Learned and Preparation for Future Pandemics

The COVID-19 pandemic has evolved since the publication of the initial American Society of Echocardiography (ASE) statements providing guidance to echocardiography laboratories. In light of new developments, the ASE convened a diverse, expert writing group to address the current state of the COVID-19 pandemic and to apply lessons learned to echocardiography laboratory operations in future pandemics. This statement addresses important areas specifically impacted by the current and future pandemics: (1) indications for echocardiography, (2) application of echocardiographic services in a pandemic, (3) infection/transmission mitigation strategies, (4) role of cardiac point-of-care ultrasound/critical care echocardiography, and (5) training in echocardiography.

ACC/AHA/ASE/ASNC/ASPC/HFSA/HRS/SCAI/SCCT/SCMR/STS 2023 Multimodality Appropriate Use Criteria for the Detection and Risk Assessment of Chronic Coronary Disease

The American College of Cardiology (ACC) Foundation, along with key specialty and subspecialty societies, conducted an appropriate use review of stress testing and anatomic diagnostic procedures for risk assessment and evaluation of known or suspected chronic coronary disease (CCD), formerly referred to as stable ischemic heart disease (SIHD). This document reflects an updating of the prior Appropriate Use Criteria (AUC) published for radionuclide imaging, stress echocardiography (echo), calcium scoring, coronary computed tomography angiography (CCTA), stress cardiac magnetic resonance (CMR), and invasive coronary angiography for SIHD. This is in keeping with the commitment to revise and refine the AUC on a frequent basis. As with the prior version of this document, rating of test modalities is provided side-by-side for a given clinical scenario. These ratings are explicitly not considered competitive rankings due to the limited availability of comparative evidence, patient variability, and the range of capabilities available in any given local setting1-4.This version of the AUC for CCD is a focused update of the prior version of the AUC for SIHD4. Key changes beyond the updated ratings based on new evidence include the following: 1. Clinical scenarios related to preoperative testing were removed and will be incorporated into another AUC document under development. 2. Some clinical scenarios and tables were removed in an effort to simplify the selection of clinical scenarios. Additionally, the flowchart of tables has been reorganized, and all clinical scenario tables can now be reached by answering a limited number of clinical questions about the patient, starting with the patient's symptom status. 3. Several clinical scenarios have been revised to incorporate changes in other documents such as pretest probability assessment, atherosclerotic cardiovascular disease (ASCVD) risk assessment, syncope, and others. ASCVD risk factors that are not accounted for in contemporary risk calculators have been added as modifiers to certain clinical scenarios. The 64 clinical scenarios rated in this document are limited to the detection and risk assessment of CCD and were drawn from common applications or anticipated uses, as well as from current clinical practice guidelines.5 These clinical scenarios do not specifically address patients having acute chest pain episodes. They may, however, be applicable in the inpatient setting if the patient is not having an acute coronary syndrome and warrants evaluation for CCD.Using standardized methodology, clinical scenarios were developed to describe common patient encounters in clinical practice focused on common applications and anticipated uses of testing for CCD. Where appropriate, the scenarios were developed on the basis of the most current ACC/American Heart Association guidelines. A separate, independent rating panel scored the clinical scenarios in this document on a scale of 1 to 9, following a modified Delphi process consistent with the recently updated AUC development methodology. Scores of 7 to 9 indicate that a modality is considered appropriate for the clinical scenario presented, midrange scores of 4 to 6 indicate that a modality may be appropriate for the clinical scenario, and scores of 1 to 3 indicate that a modality is rarely appropriate.

The Utility of Low-Dose-Dobutamine Stress Echocardiography in Patients with Heart Failure with Reduced Ejection Fraction: An Update

Despite significant advancements in medical therapy, heart failure with reduced ejection fraction (HFrEF) continues to be a significant cause of death and disability. Reversible ischaemic left ventricular dysfunction due to viable myocardium is one such contributing factor. In these cases, coronary revascularization has shown promise in improving left ventricular function and prognosis. For patients with HFrEF and wide QRS, cardiac resynchronization therapy (CRT) is an effective option to address electromechanical dyssynchrony. However, approximately 30% of patients do not respond positively to CRT, highlighting the need to refine candidate selection for this treatment. In some patients with reduced HFrEF, there is a condition known as classical low-flow, low-gradient aortic stenosis (AS) that may be observed. This condition is characterized by a low transaortic flow, which leads to reductions in both the transaortic mean gradient and aortic valve area. Decision-making regarding revascularization, CRT, and pharmacological treatment play a crucial role in managing HFrEF. Cardiac imaging can be valuable in guiding decision-making processes and assessing the prognosis of patients with HFrEF. Among the imaging modalities, dobutamine stress echocardiography has come a long way in establishing itself as a feasible, safe, effective, relatively cheap non-invasive technique. The aim of this review is to explore the current literature on the utility of low-dose stress echocardiography in diagnosing and prognosticating patients with HFrEF.

The Importance of Left Ventricular Outflow Tract and Mid-Ventricular Gradients in Stress Echocardiography: A Narrative Review

This review aims to serve as a guide for clinical practice and to appraise the current knowledge on exercise stress echocardiography in the evaluation of intraventricular obstruction in HCM, in patients with cardiac syndrome X, in athletes with symptoms related to exercise, and in patients with normal left ventricular systolic function and exercise-related unexplained tiredness. The appearance of intraventricular obstruction while exercising is considered rare, and it usually occurs in patients with hypertrophy of the left ventricle. The occurrence of intraventricular obstruction when exercising has been evidenced in patients with hypertrophic cardiomyopathy, athletes, patients with cardiac syndrome X, patients with syncope or dizziness related to exercise, and patients with dyspnea and preserved ejection fraction. The clinical significance of this observation and the exercise modality that is most likely to trigger intraventricular obstruction remains unknown. Supine exercise and lying supine after exercise are less technically demanding, but they are also less physiologically demanding than upright exercise. Importantly, in everyday life, human beings generally do not become supine after exercise, as takes place in post-exercise treadmill stress echocardiograms in most echocardiography labs. The presence of induced intraventricular obstruction might be considered when patients have exercise-related symptoms that are not understood, and to assess prognosis in hypertrophic cardiomyopathy.

An Overview of Sport Participation and Exercise Prescription in Mitral Valve Disease

The incidence of heart valve disease (HVD) has been rising over the last few decades, mainly due to the increasing average age of the general population, and mitral valve (MV) disease is the second most prevalent HVD after calcific aortic stenosis, but MV disease is a heterogeneous group of different pathophysiological diseases. It is widely proven that regular physical activity reduces all-cause mortality rates, and exercise prescription is part of the medical recommendations for patients affected by cardiovascular diseases. However, changes in hemodynamic balance during physical exercise (including the increase in heart rate, preload, or afterload) could favor the progression of the MV disease and potentially trigger major cardiac events. In young patients with HVD, it is therefore important to define criteria for allowing competitive sport or exercise prescription, balancing the positive effects as well as the potential risks. This review focuses on mitral valve disease pathophysiology, diagnosis, risk stratification, exercise prescription, and competitive sport participation selection, and offers an overview of the principal mitral valve diseases with the aim of encouraging physicians to embody exercise in their daily practice when appropriate.

Exercise-Induced Intraventricular Gradients As a Potential Cause of Sudden Cardiac Death

A 16-year-old boy reported an episode of dizziness related to intense training six months before an episode of aborted sudden death. The screening required for competitive sports practice was normal. There were no personal or familial antecedents of sudden death or heart disease. After winning a triathlon competition, he experienced a cardiac arrest episode. He received defibrillation with the return of spontaneous circulation. A medical evaluation that included electrocardiogram (ECG) and echocardiogram had normal results. A complete study including cardiac MRI, coronary CT angiography, a genetic study for heart disease, the flecainide test, and a stress echocardiogram with ergometrine was done, and all results were normal. During a Holter ECG and exercise stress echo, isolated premature ventricular complexes were detected. During the effort treadmill stress echocardiogram, the athlete developed a significant intraventricular obstruction with an end-systolic peak, without systolic anterior movement of the mitral valve, which disappeared in the first minute of the recovery. We highlight the possible cause-effect relation between the events.

Characterization of the circulating transcriptome expression profile and identification of novel miRNA biomarkers in hypertrophic cardiomyopathy

BACKGROUND

Hypertrophic cardiomyopathy (HCM), one of the most common genetic cardiovascular diseases, but cannot be explained by single genetic factors. Circulating microRNAs (miRNAs) are stable and highly conserved. Inflammation and immune response participate in HCM pathophysiology, but whether the miRNA profile changes correspondingly in human peripheral blood mononuclear cells (PBMCs) with HCM is unclear. Herein, we aimed to investigate the circulating non-coding RNA (ncRNA) expression profile in PBMCs and identify potential miRNAs for HCM biomarkers.

METHODS

A Custom CeRNA Human Gene Expression Microarray was used to identify differentially expressed (DE) mRNAs, miRNAs, and ncRNAs (including circRNA and lncRNA) in HCM PBMCs. Weighted correlation network analysis (WGCNA) was used to identify HCM-related miRNA and mRNA modules. The mRNAs and miRNAs from the key modules were used to construct a co-expression network. Three separate machine learning algorithms (random forest, support vector machine, and logistic regression) were applied to identify potential biomarkers based on miRNAs from the HCM co-expression network. Gene Expression Omnibus (GEO) database (GSE188324) and experimental samples were used for further verification. Gene set enrichment analysis (GSEA) and competing endogenous RNA (ceRNA) network was used to determine the potential functions of the selected miRNAs in HCM.

RESULTS

We identified 1194 DE-mRNAs, 232 DE-miRNAs and 7696 DE-ncRNAs in HCM samples compared with normal controls from the microarray data sets. WGCNA identified key miRNA modules and mRNA modules evidently associated with HCM. We constructed a miRNA‒mRNA co-expression network based on these modules. A total of three hub miRNAs (miR-924, miR-98 and miR-1) were identified by random forest, and the areas under the receiver operator characteristic curves of miR-924, miR-98 and miR-1 were 0.829, 0.866, and 0.866, respectively.

CONCLUSIONS

We elucidated the transcriptome expression profile in PBMCs and identified three hub miRNAs (miR-924, miR-98 and miR-1) as potential biomarkers for HCM detection.

Effects of Mineralocorticoid Receptor Antagonists in Early-Stage Heart Failure With Preserved Ejection Fraction

Background

Hospitalization with a first episode of heart failure (HF) is a serious event associated with poor clinical outcomes in HF with preserved ejection fraction (HFpEF). Identification of HFpEF via detection of elevated left ventricular filling pressure at rest or during exercise may allow early intervention. Benefits of treatment with mineralocorticoid receptor antagonists (MRAs) in established HFpEF have been reported, but use of MRAs is not well studied in early HFpEF without prior HF hospitalization.

Methods

We retrospectively studied 197 patients with HFpEF who did not have prior hospitalization but had been diagnosed by exercise stress echocardiography or catheterization. We examined changes in natriuretic peptide levels and echocardiographic parameters reflecting diastolic function following MRA initiation.

Results

Of the 197 patients with HFpEF, MRA treatment was initiated for 47 patients. After a median 3-month follow-up, reduction in N-terminal pro-B-type natriuretic peptide levels from baseline to follow-up was greater in patients treated with MRA than in those who were not (median, -200 pg/mL [interquartile range, -544 to -31] vs 67 pg/mL [interquartile range, -95 to 456], P < 0.0001 in 50 patients with paired data). Similar results were observed for the changes in B-type natriuretic peptide levels. Reduction in the left atrial volume index was also greater in the MRA-treated group than in the non-MRA-treated group after a median 7-month follow-up (77 patients with paired echocardiographic data). Patients with lower left ventricular global longitudinal strain experienced a greater reduction in N-terminal pro-B-type natriuretic peptide levels following MRA treatment. In the safety assessment, MRA modestly decreased renal function but did not change potassium levels.

Conclusions

Our results suggest that MRA treatment has potential benefits for early-stage HFpEF.

Effects of continuous positive airway pressure therapy on left ventricular performance in patients with severe obstructive sleep apnea

We investigated myocardial performance concerning obstructive sleep apnea (OSA) severity and the benefits of continuous positive airway pressure (CPAP) therapy. In this randomized sham-controlled trial, 52 patients (mean age, 49 years; 92%, males; mean AHI, 59) with severe OSA were randomly assigned to receive either CPAP or sham treatment for 3 months. The severity of OSA was determined using the apnea/hypopnea index (AHI), oxygen desaturation index (ODI), percentage of sleep time below 90% oxygen saturation (T90), and average O₂ saturation during sleep (mean SpO₂). We compared the changes in myocardial work after 3 months of CPAP (n = 26) versus the sham group (n = 26) at rest and during an exercise stress test. Unlike AHI or ODI, indices of hypoxemia including T90 and mean SpO₂ were significantly correlated with global constructive work, as defined by work of left ventricle (LV) that contributes to LV ejection during systole (T90, β = 0.393, p = 0.012; mean SpO₂, β = 0.331, p = 0.048), and global wasted work (GWW), as defined by work of LV that does not contribute to LV ejection (T90, β = 0.363, p = 0.015; mean SpO₂, β =  - 0.370, p = 0.019). After 3 months, GWW decreased (80.0 ± 49.2 to 60.8 ± 26.3, p = 0.009) and global work efficiency increased (94.0 ± 4.5 to 95.7 ± 2.0, p = 0.008) in the CPAP group compared to those in the sham group. At the 3-month follow-up exercise stress echocardiography, worsening of GWW during exercise was significantly decreased in the CPAP group compared to that in the sham group (p = 0.045 at 50 W). Hypoxemia indices were closely associated with myocardial performance in patients with severe OSA. CPAP treatment for 3 months improved left ventricular myocardial performance by decreasing wasted work and increasing work efficacy compared to the sham treatment.

Diagnostic value of expired gas analysis in heart failure with preserved ejection fraction

Cardiopulmonary exercise testing (CPET) may potentially differentiate heart failure (HF) with preserved ejection fraction (HFpEF) from noncardiac causes of dyspnea (NCD). While contemporary guidelines for HF recommend using CPET for identifying causes of unexplained dyspnea, data supporting this practice are limited. This study aimed to determine the diagnostic value of expired gas analysis to distinguish HFpEF from NCD. Exercise stress echocardiography with simultaneous expired gas analysis was performed in patients with HFpEF (n = 116) and those with NCD (n = 112). Participants without dyspnea symptoms were also enrolled as controls (n = 26). Exercise capacity was impaired in patients with HFpEF than in controls and those with NCD, evidenced by lower oxygen consumption (VO₂), but there was a substantial overlap between HFpEF and NCD. Receiver operating characteristic curve analyses showed modest diagnostic abilities of expired gas analysis data in differentiating individuals with HFpEF from the controls; however, none of these variables clearly differentiated between HFpEF and NCD (all areas under the curve < 0.61). Expired gas analysis provided objective assessments of exercise capacity; however, its diagnostic value in identifying HFpEF among patients with symptoms of exertional dyspnea was modest.

Disproportionate exercise-induced pulmonary hypertension in relation to cardiac output in heart failure with preserved ejection fraction: a non-invasive echocardiographic study

AIMS

Pulmonary hypertension (PH) and pulmonary vascular remodelling are common in patients with heart failure with preserved ejection fraction (HFpEF). Many patients with HFpEF demonstrate an abnormal pulmonary haemodynamic response to exercise that is not identifiable at rest. This can be estimated non-invasively by the mean pulmonary artery pressure-cardiac output relationship (mPAP/CO slope). We sought to characterize the pathophysiology of disproportionate exercise-induced PH in relation to CO (DEi-PH) and its prognostic impact in patients with HFpEF.

METHODS AND RESULTS

A total of 345 patients (166 HFpEF and 179 controls) underwent ergometry exercise stress echocardiography with simultaneous expired gas analysis. DEi-PH was defined as the mPAP/CO slope >5.2 mmHg/L/min (median value). At rest, there were no differences in right ventricular (RV) function and severity of PH between HFpEF patients with and without DEi-PH. Compared with controls (n = 179) and HFpEF without DEi-PH (n = 83), HFpEF with DEi-PH (n = 83) demonstrated worse exercise capacity (lower peak oxygen consumption), depressed RV systolic function, impaired RV-pulmonary artery coupling, limitation in CO augmentation, more right-sided congestion, and worse ventilatory efficiency (higher minute ventilation vs. carbon dioxide volume) during peak exercise. Kaplan-Meier analyses showed that HFpEF patients with DEi-PH had higher rates of composite outcomes of all-cause mortality or heart failure events than those without (log-rank p = 0.0002).

CONCLUSION

Patients with HFpEF and DEi-PH demonstrated distinct pathophysiologic features that become apparent only during exercise. These data suggest that DEi-PH is a pathophysiologic phenotype of HFpEF and reinforce the importance of exercise stress echocardiography for detailed characterization of HFpEF.

Recognized and Unrecognized Value of Echocardiography in Guideline and Consensus Documents Regarding Patients With Chest Pain

Guideline and consensus documents have recently been published on the important topic of the noninvasive evaluation of patients presenting with chest pain (CP) or patients with known acute or chronic coronary syndromes. Authors for these documents have included members representing multispecialty imaging societies, yet the process of generating consensus and the need to produce concise written documents have led to a situation where the particular advantages of echocardiography are overlooked. Broad guidelines such as these can be helpful when it comes to "when to do" noninvasive cardiac testing, but they do not pretend to offer nuances on "how to do" noninvasive cardiac testing. This report details the particular value of echocardiography and potential explanations for its understated role in recent guidelines. This report is categorized into the following sections: (1) impact of the level of evidence on guideline creation; (2) versatility of echocardiography in the assessment of CP and the inimitable role for echo Doppler echocardiography in the assessment of dyspnea; (3) value of point-of-care ultrasound in assessing CP and dyspnea; and (4) the future role of echocardiography in ischemic heart disease.

Atrial Cardiomyopathy with Impaired Functional Reserve in Patients with Paroxysmal Atrial Fibrillation

BACKGROUND

Impaired atrial functional reserve during exercise may represent an early stage of atrial cardiomyopathy. To test this hypothesis, the authors evaluated left atrial (LA) and left ventricular (LV) function reserve during exercise in patients with paroxysmal atrial fibrillation (PAF).

METHODS

Sixty-one patients with PAF undergoing radiofrequency catheter ablation and 38 healthy control subjects were prospectively enrolled. LV global longitudinal strain and LA reservoir strain (RS) were measured at rest and during supine bicycle exercise. To identify the early stage of atrial cardiomyopathy without LA structural remodeling, patients with PAF were divided into two groups according to LA volume index (LAVI): atrial fibrillation (AF) group 1 (LAVI ≥ 34 mL/m²) and AF group 2 (LAVI < 34 mL/m²).

RESULTS

LV ejection fraction and global longitudinal strain did not differ between patients with AF and control subjects. LAVI and LA RS did not differ between AF group 2 and control subjects. During exercise, LV global longitudinal strain improved in all groups. Increases in LA RS were attenuated in both AF groups, which also exhibited lower LA functional reserve index than the control subjects. Although resting LA RS was similar between AF group 2 and control subjects, LA functional reserve index was significantly lower in AF group 2. LA functional reserve index was associated with risk for AF recurrence (hazard ratio, 0.852; 95% CI, 0.736-0.988).

CONCLUSIONS

Atrial cardiomyopathy can be anticipated by impaired LA functional reserve during exercise in patients with AF, even in those with normal-sized left atria. Atrial cardiomyopathy occurs independently of changes in LV function and is associated with the recurrence of AF in patients with PAF after radiofrequency catheter ablation.

Utility of E/e' Ratio During Low-Level Exercise to Diagnose Heart Failure With Preserved Ejection Fraction

BACKGROUND

E/e' ratio during exercise is the key parameter in identifying elevated pulmonary capillary wedge pressure (PCWP), and thus heart failure with preserved ejection fraction (HFpEF). However, its diagnostic value is limited when mitral inflow or tissue velocities are fused during elevated heart rate.

OBJECTIVES

The authors hypothesized that E/e' ratio during low-level (20 W) exercise (E/e'20W) can help diagnose HFpEF.

METHODS

Ergometric exercise stress echocardiography was performed in 215 dyspneic patients with an EF ≥50%. The authors determined the feasibility of E/e' ratio at each stage (frequency of patients who had measurable E/e' without E-A fusion among 215 participants) and examined whether E/e'20W could predict normal E/e' ratio during peak exercise (E/e'peak ≤15). The authors also evaluated whether E/e'20W could predict normal PCWP during exercise (PCWP <25 mm Hg) in a subset of participants (n = 45) who underwent exercise right heart catheterization.

RESULTS

The feasibility of the E/e' ratio decreased from 100% at rest to 96.3% during 20-W exercise and 74.9% during peak exercise caused by E-A fusion. In patients with E/e'peak >15, there was an increase in E/e' ratio from rest to 20-W exercise (11.2 ± 2.1 to 16.3 ± 3.5; P < 0.0001), but it did not change significantly from 20-W exercise to peak exercise (P = 0.12). E/e'20W predicted E/e'peak ≤15 (AUC: 0.91; P < 0.0001) with the cutoff value of ≤12.4 showing high specificity (94%) and positive predictive value (98%). During 20-W exercise, 93% of the HFpEF patients developed PCWP ≥25 mm Hg. E/e'20W predicted normal PCWP during exercise (AUC: 0.77; P = 0.01) with the cutoff value of ≤12.4 showing high specificity (83%).

CONCLUSIONS

E/e' ratio during low-level exercise is highly feasible and predicts normal E/e' ratio or PCWP during peak exercise with high specificity. These data suggest that E/e'20W could be used as an alternative to the peak exercise value to rule out HFpEF in patients with dyspnea.

Myocardial mechanics of percutaneous intramyocardial septal radiofrequency ablation

OBJECTIVE

Echocardiography-guided Percutaneous IntraMyocardial Septal Radiofrequency Ablation (PIMSRA, Liwen procedure) is a novel treatment option for hypertrophic obstructive cardiomyopathy (HOCM). The impact of PIMSRA on myocardial mechanics is unknown.

METHODS

Between October 2016 and June 2019, PIMSRA and 3-dimentional speckle tracking echocardiography were performed in 82 patients. Echocardiographic imaging, qualitative and quantitative clinical assessment were completed at baseline, immediately postprocedure and 1-year follow-up.

RESULTS

There was a significant reduction in the peak left ventricular outflow tract (LVOT) gradients immediately following PIMSRA and at 1-year follow-up (resting gradients: from 83.50 (61.25) to 23.00 (41.75) mm Hg, p<0.001 and 13.50 (21.75) mm Hg, p<0.001, respectively; stress-induced gradients: from 118.25 (96.02) to 47.00 (74.50) mm Hg (1 year), p<0.001). There was an improvement in exercise time on stress echocardiography (p<0.001) and distance by 6 min walk test (p=0.034). Immediately after PIMSRA, there was a significant reduction in radial and circumferential strain in the ablated segments (p<0.001), with no change of longitudinal strain. At 1-year follow-up, the radial and circumferential strain recovered in the ablated segments. Meanwhile, left ventricular regional and global longitudinal strain had improved significantly (p<0.05).

CONCLUSIONS

PIMSRA is an effective treatment for symptomatic HOCM that resulted in a sustained improvement in exercise capacity, a persistent decrease in LVOT gradient, and a measurable increase in myocardial contractile function.

TRIAL REGISTRATION NUMBER

NCT04777188.

Incremental diagnostic value of post-exercise lung congestion in heart failure with preserved ejection fraction

AIMS

Lung ultrasound (LUS) may unmask occult heart failure with preserved ejection fraction (HFpEF) by demonstrating an increase in extravascular lung water (EVLW) during exercise. Here, we sought to examine the dynamic changes in ultrasound B-lines during exercise to identify the optimal timeframe for HFpEF diagnosis.

METHODS AND RESULTS

Patients with HFpEF (n = 134) and those without HF (controls, n = 121) underwent a combination of exercise stress echocardiography and LUS with simultaneous expired gas analysis to identify exercise EVLW. Exercise EVLW was defined by B-lines that were newly developed or increased during exercise. The E/e' ratio peaked during maximal exercise and immediately decreased during the recovery period in patients with HFpEF. Exercise EVLW was most prominent during the recovery period in patients with HFpEF, while its prevalence did not increase from peak exercise to the recovery period in controls. Exercise EVLW was associated with a higher E/e' ratio and pulmonary artery pressure, lower right ventricular systolic function, and elevated minute ventilation to carbon dioxide production (VE vs. VCO2) slope during peak exercise. Increases in B-lines from rest to the recovery period provided an incremental diagnostic value to identify HFpEF over the H2FPEF score and resting left atrial reservoir strain.

CONCLUSION

Exercise EVLW was most prominent early during the recovery period; this may be the optimal timeframe for imaging ultrasound B-lines. Exercise stress echocardiography with assessments of recovery EVLW may enhance the diagnosis of HFpEF.

Determinants of exercise capacity in patients with heart failure without left ventricular hypertrophy

BACKGROUND

Determinants of exercise intolerance in a phenotype of heart failure with preserved ejection fraction (HFpEF) with normal left ventricular (LV) structure have not been fully elucidated.

METHODS

Cardiopulmonary exercise testing and exercise-stress echocardiography were performed in 44 HFpEF patients without LV hypertrophy. Exercise capacity was determined by peak oxygen consumption (peak VO₂). Doppler-derived cardiac output (CO), transmitral E velocity, systolic (LV-s') and early diastolic mitral annular velocities (e'), systolic pulmonary artery (PA) pressure (SPAP), tricuspid annular plane systolic excursion (TAPSE), and peak systolic right ventricular (RV) free wall velocity (RV-s') were measured at rest and exercise. E/e' and TAPSE/SPAP were used as an LV filling pressure parameter and RV-PA coupling, respectively.

RESULTS

During exercise, CO, LV-s', RV-s', e', and SPAP were significantly increased (p < 0.05 for all), whereas E/e' remained unchanged and TAPSE/SPAP was significantly reduced (p < 0.001). SPAP was higher and TAPSE/SPAP was lower at peak exercise in patients showing lower-half peak VO₂. In univariable analyses, LV-s' (R = 0.35, p = 0.022), SPAP (R = -0.40, p = 0.008), RV-s' (R = 0.47, p = 0.002), and TAPSE/SPAP (R = 0.42, p = 0.005) were significantly correlated with peak VO₂. In multivariable analyses, not only SPAP, but also TAPSE/SPAP independently determined peak VO₂ even after the adjustment for clinically relevant parameters.

CONCLUSIONS

In HFpEF patients without LV hypertrophy, altered RV-PA coupling by exercise could be associated with exercise intolerance, which might not be caused by elevated LV filling pressure.

Recommendations for the Use of Echocardiography in the Evaluation of Rheumatic Heart Disease: A Report from the American Society of Echocardiography

Acute rheumatic fever and its chronic sequela, rheumatic heart disease (RHD), pose major health problems globally, and remain the most common cardiovascular disease in children and young people worldwide. Echocardiography is the most important diagnostic tool in recognizing this preventable and treatable disease and plays an invaluable role in detecting the presence of subclinical disease needing prompt therapy or follow-up assessment. This document provides recommendations for the comprehensive use of echocardiography in the diagnosis and therapeutic intervention of RHD. Echocardiographic diagnosis of RHD is made when typical findings of valvular and subvalvular abnormalities are seen, including commissural fusion, leaflet thickening, and restricted leaflet mobility, with varying degrees of calcification. The mitral valve is predominantly affected, most often leading to mitral stenosis. Mixed valve disease and associated cardiopulmonary pathology are common. The severity of valvular lesions and hemodynamic effects on the cardiac chambers and pulmonary artery pressures should be rigorously examined. It is essential to take advantage of all available modalities of echocardiography to obtain accurate anatomic and hemodynamic details of the affected valve lesion(s) for diagnostic and strategic pre-treatment planning. Intraprocedural echocardiographic guidance is critical during catheter-based or surgical treatment of RHD, as is echocardiographic surveillance for post-intervention complications or disease progression. The role of echocardiography is indispensable in the entire spectrum of RHD management.

Peak exercise myocardial deformation indices during cardiopulmonary exercise testing are associated with exercise capacity and ventilatory efficiency in patients with dilated cardiomyopathy

OBJECTIVE

Little is known about the exercise-induced changes in the multidimensional mechanical properties of the heart. We aimed to evaluate the myocardial deformation indices (MDI) at rest and their response at peak exercise during the same cardiopulmonary exercise testing (CPET) session, investigating their relationship to exercise capacity and ventilatory sufficiency in dilated cardiomyopathy (DCM) patients.

METHODS

We evaluated left ventricular (LV) function using speckle tracking imaging (STI) at rest and peak exercise during the same CPET session in 57 idiopathic DCM patients in New York Heart Association (NYHA) I-II class [54 ± 12 years, 42 males, ejection fraction (EF) 33 ± 9%]. We measured global longitudinal strain (GLS), longitudinal strain rate at systole (LSRS) and diastole (LSRD), and circumferential strain rate (CircS).

RESULTS

Resting GLS, LSRS, and LSRD were impaired compared with the predicted values but were improved at peak exercise (p < 0.001). All MDI at rest and/or at peak exercise were related to several CPET-derived parameters, including peak VO₂, load, O₂ pulse, and VE/VCO₂ slope. Peak exercise LSRS > -1.10 sec^-1 (AUC = 0.80, p < 0.001) and GLS > -13% (AUC = 0.81, p = 0.002) predicted impaired exercise capacity (peak VO₂ < 20 ml/min/kg) and ventilatory inefficiency (VE/VCO₂ slope>34). In multiple regression analysis, peak exercise LSRS and GLS were independently related to the peak VO₂ (Beta = -0.39, p = 0.003) and VE/VCO₂ slope (Beta = 0.35, p = 0.02), respectively.

CONCLUSIONS

Peak exercise LSRS and GLS in NYHA I-II DCM patients subjected to CPET were associated with aerobic exercise capacity and ventilatory efficiency. Consequently, LSRS and GLS at peak exercise, through their association with CPET-derived CV risk indices, may underline the severity of heart failure and predict future CV events in this DCM population.

Multimodality Imaging in Valvular Structural Interventions

Structural valvular interventions have skyrocketed in the past decade with new devices becoming available and indications for patients who would previously have been deemed inoperable. Furthermore, while echocardiography is the main imaging tool and the first line for patient screening, cardiac magnetic resonance and CT are now essential tools in pre-planning and post-procedural follow-up. This review aims to address imaging modalities and their scope in aortic, mitral and tricuspid structural valvular interventions, including multimodality imaging. Pulmonary valve procedures, which are mostly carried out in patients with congenital problems, are discussed. This article presents a guide on individualised imaging approcahes on each of the available interventional procedures.

First-in-man application of Liwen RF™ ablation system in the treatment of drug-resistant hypertrophic obstructive cardiomyopathy

OBJECTIVES

This study sought to evaluate the clinical applicability of the Liwen Liu RF™ ablation system for percutaneous intramyocardial septal radiofrequency ablation (PIMSRA).

BACKGROUND

Data on new cardiac radiofrequency ablation devices for the treatment of hypertrophic obstructive cardiomyopathy (HOCM) are limited.

MATERIALS AND METHODS

From July 2019 to July 2020, a total of 68 patients with drug-resistant HOCM, who underwent PIMSRA with the Liwen RF™ ablation system, which has an ablation electrode of stepless adjustable length, were prospectively enrolled. Safety endpoints included, amongst others, the occurrence of pericardial effusion and/or hemorrhage, cardiac arrhythmias, device failure and procedural death. The reduction in left ventricular outflow tract (LVOT) gradients at 12 months follow-up were used as a surrogate marker for device efficacy.

RESULTS

All procedures were technically successful. The total energy output time of the system was 75.8 (IQR: 30.0) min, and the average power was 43.61 ± 13.34 watts. No ablation system error occurred. The incidence of pericardial effusion or hemorrhage, transient arrhythmia and resuscitation was 8.8, 39.7, and 1.5% during procedure, respectively. None of the patients died. During 30-day follow-up, there were no complications with the exception of a pericardial effusion in one patient (1.5%). No further complications were reported after 30 days. The patients' resting [baseline: 75 (IQR: 48) vs. 12-months: 12 (IQR: 19) mmHg, p < 0.001] and provoked [baseline: 122 (IQR: 53) vs. 12-months: 41 (IQR: 59) mmHg, p < 0.001] LVOT gradients decreased significantly during follow-up.

CONCLUSION

In this study, we demonstrate the safety and feasibility of the Liwen RF™ ablation system to treat HOCM. The system allows for significant and sustainable LVOT gradient reduction during 12-months of follow-up. Hence, the Liwen RF™ ablation system is a promising new device that has the potential to become an alternative to existing septal reduction concepts in HOCM patients.