Echocardiography, Stress – ABC CARDIOL

ABCIC

Editorial

ABCDE Protocol in Stress Echocardiography

José Luis de Castro e Silva Pretto et al. Clarissa Borguezan Daros

A for Asynergy

This is based on the presumable myocardial contractility alteration induced by stress in the presence of flow-limiting coronary stenosis. The substrate supply-demand imbalance leads to a reduction in myocardial radial thickening, a parameter sometimes limited by its semi-quantitative and subjective nature. Operator dependency can be minimized (but not eliminated) by specialized training and the adoption of conservative reading measures, as well as the accreditation and quality control of advanced echocardiography laboratories.

The regional motility assessment indicates that the higher the number of affected segments (universally defined), the worse the prognosis. This parameter is viewed as stenosis centered and has its value limited outside the epicardial coronary disease context.

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ABCIC

Review Article

Stress Echocardiography Using Real-Time 3D Imaging

José Roberto Matos-Souza et al. Guilherme De Rossi

Abstract

The need to examine the heart using a three-dimensional (3D) tool is not new. This complex and dynamic organ has always required 3D and real-time understanding. Without this feature, the examiner has to transform two-dimensional images to understand its volume, which requires complex knowledge and approximation interactions. Echocardiography was invented three decades ago, and its improvements resulted in commercial products at the beginning of the century. Some studies demonstrate 3D equivalence with gains in handling the necessary time. We use triplane modalities in our routine, with time gain and less stress on the examiner’s upper limb. Thus, 3D examinations can answer more complex questions and provide a more geometric approach to contraction, with thickening being analyzed in the background.

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ABCIC

Original Article

Diastolic Function Assessment with Doppler Echocardiography and Two-Dimensional Strain

José Maria Del Castillo et al. Eugenio Soares de Albuquerque Carlos Antônio da Mota Silveira Diana Patrícia Lamprea Antonia Dulcineide Medeiros Sena

Summary

Background

The evaluation of left ventricular (LV) diastolic dysfunction presents a significant number of indeterminate dysfunctions, especially when ejection fraction (EF) is preserved. Global longitudinal strain (GLS) and systolic strain rate (SSR) and early diastolic strain rate (EDSR) may be useful for reclassifying diagnosed patients.

Objective

To evaluate, using GLS, SSR and EDSR, patients with diastolic dysfunction, compare with healthy individuals, and determine the additive value of the method.

Methods

The study included 149 patients (age 62.2 ± 10.6) with diastolic dysfunction (49.7% grade 1; 15.4% grade 2; 18.1% grade 3 and 16.8% unspecified) and 189 healthy individuals (age 44.5 ± 13.3). Left ventricular (LV) and left atrial (LA) dimensions and function, mitral and tissue Doppler velocities and their ratios, GLS, SSR and EDSR have been determined. Data evaluation using the Kolmogorov-Smirnoff, Kruskal-Wallis tests, multiple regression analysis and area under the ROC curve. Data were considered significant when p < 0.05.

Results

In diastolic dysfunction, LV dimensions and thickness were increased and EF was lower. Mitral and tissue Doppler revealed abnormalities and LA volume and tricuspid regurgitation velocity were increased. GLS and EDSR were decreased in dysfunction grade 2 and 3 and EDSR was decreased in dysfunction grade 1, correlating better with diastolic dysfunction. The ROC cutoff value for the EDSR was 1.0 s^-1.

Conclusion

Diastolic dysfunction supplemented with myocardial strain rate seems to add sensitivity and specificity where the diastolic function is indeterminate and may be used for reclassifying these patients. (Arq Bras Cardiol: Imagem cardiovasc. 2017;30(2):46-53)

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ABCIC

Viewpoint

Coronary Tomography Angiography and a New View on How to Investigate Coronary Artery Disease — New English Guideline

Marcio Sommer Bittencourt

[…]

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ABCIC

Original Article

Analysis of the Safety and Feasibility of Dobutamine Stress Echocardiography in Ten Thousand and Six Tests of a General Population

José Sebastião de Abreu et al. Tereza Cristina Diógenes Pinheiro Marília Esther Benevides de Abreu Ana Gardenia Liberato Ponte Farias Marcia Maria Carneiro

Abstract

Background

Adverse effects and inconclusive results may occur on dobutamine stress echocardiography.

Objective

To assess the safety and feasibility of dobutamine stress echocardiography in a large general population.

Methods

A total of 10,006 dobutamine stress echocardiographies were performed between July 1996 and September 2007. Dobutamine was administered in four stages (10, 20, 30, and 40 μcg·kg^-1·min^-1) to research myocardial ischemia starting with 5 μcg·kg^-1·min^-1 to analyze myocardial viability. Atropine was started according to the protocols used in the period. Clinical, hemodynamic, and adverse effect data associated with dobutamine stress echocardiography findings were verified.

Results

Typical angina (8.9%), hypertensive peak (1.7%), isolated ventricular ectopias (31%), supraventricular tachyarrhythmia (1.89%), atrial fibrillation (0.76%), and non-sustained ventricular tachycardia (0.6%) occurred during dobutamine stress echocardiography. The adverse effects occurred more frequently in patients with positive dobutamine stress echocardiography findings for ischemia than in those with negative findings. Paradoxical sinus deceleration (0.16%) did not occur in cases of positive dobutamine stress echocardiography findings. Three severe complications occurred in cases that tested positive for ischemia on dobutamine stress echocardiography: two (0.02%) of ventricular fibrillation and one of acute coronary syndrome (0.01%). There were no cases of sustained ventricular tachycardia, cardiac rupture, asystole, or death. Compared to those with complete tests, patients with inconclusive results used less atropine (81.5% versus 49.9%, p < 0.001) and more beta-blockers (4.7% versus 19%, p < 0.001) and more commonly presented with a hypertensive peak (1.1% versus 14.2%, p = 0.0001) or non-sustained ventricular tachycardia (0.5% versus 2.2%, p < 0.001).

Conclusion

When properly performed, dobutamine stress echocardiography is safe and has high feasibility.

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ABCIC

Review Article

Exercise Stress Echocardiography in Hypertrophic Cardiomyopathy: How, When and Why?

Joselina Luzia Menezes Oliveira et al. Katia Oliveira Nunes Leal Larissa Rebeca da Silva Tavares Irlaneide da Silva Tavares … Luiz Flávio Galvāo Gonçalves Daniel Pio de Oliveira Ursula Maria Moreira Costa Burgos Eduardo José Ferreira José Oliveira Belem Marilia Marques Aquino Antonio Carlos Sobral Sousa

Abstract

Historically, the role of exercise stress echocardiography in the management of hypertrophic cardiomyopathy has been neglected in clinical practice according to the analysis of the 2002 Guidelines of the American College of Cardiology/ American Heart Association, which recommended caution use of this methodology in patients with hypertrophic cardiomyopathy due to the risk of both cardiac arrhythmia and hemodynamic collapse on exertion. Exercise stress testing in patients with hypertrophic cardiomyopathy is currently part of the routine assessment of symptomatic patients with or without a resting left ventricular outflow tract gradient < 50 mmHg. For this group, it is a safe and reliable method for measuring the left ventricular outflow tract gradient during exertion and a solid differentiator of patients with nonobstructive hypertrophic cardiomyopathy (absent gradient, both at rest and on exertion) from those with labile gradients (absent gradient at rest and present on exertion). Therefore, in the assessment of hypertrophic cardiomyopathy, exercise stress is equally useful for quantifying the degree of mitral regurgitation and left ventricular segmental contractility changes as well as assessing left ventricular diastolic function on exertion and is able to predict the future development of heart failure symptoms. The method is also important for determining different treatment strategies for each patient, from surgical myomectomy or alcohol septal ablation for those with a labile gradient, limiting symptoms, and who refractory to drug treatment to heart transplantation for those without a gradient.

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Original Article

An Alternative Method to Calculate Simplified Projected Aortic Valve Area at Normal Flow Rate

Joana Sofia Silva Moura Ferreira et al. Nádia Moreira Rita Ferreira Sofia Mendes … Rui Martins Maria João Ferreira Mariano Pego

Abstract

Background:

Simplified projected aortic valve area (EOA_proj) is a valuable echocardiographic parameter in the evaluation of low flow low gradient aortic stenosis (LFLG AS). Its widespread use in clinical practice is hampered by the laborious process of flow rate (Q) calculation.

Objetive:

This study proposes a less burdensome, alternative method of Q calculation to be incorporated in the original formula of EOA_proj and measures the agreement between the new proposed method of EOA_proj calculation and the original one.

Methods:

Retrospective observational single-institution study that included all consecutive patients with classic LFLG AS that showed a Q variation with dobutamine infusion ≥ |15|% by both calculation methods.

Results:

Twenty-two consecutive patients with classical LFLG AS who underwent dobutamine stress echocardiography were included. Nine patients showed a Q variation with dobutamine infusion calculated by both classical and alternative methods ≥ |15|% and were selected for further statistical analysis. Using the Bland-Altman method to assess agreement we found a systematic bias of 0,037 cm² (95% CI 0,004 – 0,066), meaning that on average the new method overestimates the EOA_proj in 0,037 cm² compared to the original method. The 95% limits of agreement are narrow (from -0,04 cm² to 0,12 cm²), meaning that for 95% of individuals, EOA_proj calculated by the new method would be between 0,04 cm² less to 0,12 cm² more than the EOA_proj calculated by the original equation.

Conclusion:

The bias and 95% limits of agreement of the new method are narrow and not clinically relevant, supporting the potential interchangeability of the two methods of EOA_proj calculation. As the new method requires less additional measurements, it would be easier to implement in clinical practice, promoting an increase in the use of EOA_proj.

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IJCS

Original Article

Low to Moderate Alcohol Consumption and Myocardial Ischemia on Exercise Stress Echocardiography

Vítor Joaquim Barreto Fontes et al. Maria Júlia Silveira Souto Antônio Carlos Sobral Sousa Enaldo Vieira de Melo … Flávio Mateus do Sacramento Conceição Caio José Coutinho Leal Telino Mirella Sobral Silveira Jéssica Aparecida de Santana Dória Carlos José Oliveira de Matos Joselina Luzia Menezes Oliveira

Abstract

Background:

The impact of alcohol consumption on the development of myocardial ischemia remains uncertain. Studies diverge whether low to moderate alcohol consumption provides cardioprotection or whether it is a risk factor for myocardial ischemia.

Objective:

To study the relationship between low to moderate alcohol consumption and myocardial ischemia on exercise stress echocardiography (ESE).

Methods:

Cross-sectional study with 6,632 patients with known or suspected coronary artery disease undergoing ESE between January/2000 and December/2015. The patients were divided into two groups: G1, composed of 2,130 (32.1%) patients whose report showed maximal consumption of 1 drink per day on average for women or of 2 drinks per day for men; G2, composed of individuals denying any alcohol consumption. For comparing between the groups, Student t test was used for quantitative variables, and chi-square test or Fisher exact test, for categorical variables. The significance level adopted was p < 0.05. Logistic regression was also used to evaluate independent risk factors for myocardial ischemia.

Results:

G1 had a higher number of men (77.1%; p < 0.001), lower mean age (54.8 ± 10.3 years old; p < 0.001) and higher frequency of myocardial ischemia on ESE (p = 0.014). Age, male sex, dyslipidemia, systemic arterial hypertension, diabetes mellitus, smoking and family history were independently associated with myocardial ischemia on ESE. Independent association between low to moderate alcohol consumption and myocardial ischemia on ESE (OR 0.96; 95%CI: 0.83 to 1.11) was not observed. However, age, male sex, smoking and dyslipidemia were associated with alcohol consumption.

Conclusion:

Low to moderate alcohol consumption was not an independent predictor of myocardial ischemia on ESE. Nevertheless, we observed a predominance of the male sex, dyslipidemia and smoking habit, important predictors of myocardial ischemia, in the group of alcohol consumers.

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ABC

Case Report

Symptomatic Exercise-induced Intraventricular Gradient in Competitive Athlete

Helder Dores et al. Lígia Mendes António Ferreira Jose Ferreira Santos

Case Report

We describe the case of a 17-year-old caucasian male tennis player, training a mean of 20-24h/week, refereed for evaluation in Sport’s Cardiology clinic due to symptoms of dizziness on strenuous exercise, relieving soon after decubitus. The athlete denied other concomitant complaints, namely thoracic pain, palpitations, syncope or decrease in physical performance. Although this is the most symptomatic episode, he revealed other prior episodes with similar presentation, but less intense and occurring in environments with high temperatures. Personal/family history was unremarkable and all pre-competitive evaluations were normal and without restrictions for competitive sport. Physical examination did not show significant findings – cardiac evaluation was normal, heart rate and blood pressure at rest were 52 bpm 121/64mmHg respectively.

The 12-lead electrocardiogram and transthoracic echocardiogram did not show pathological findings, only cardiac physiological adaptations to exercise (). Subsequently the athlete underwent a treadmill exercise stress echocardiogram revealing an excellent functional capacity (19’09’’ of Bruce protocol, 19.3METs), but with reproduction of symptoms (dizziness) in the peak of exercise with simultaneous decrease in systolic blood pressure (185➔90mmHg) and detection of intraventricular gradient (IVG) – at least 69mmHg (). In the first minute of recovery the symptoms disappeared and blood pressure normalized.

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ABC

Original Article

Prognostic Value of Coronary Flow Reserve Obtained on Dobutamine Stress Echocardiography and its Correlation with Target Heart Rate

José Sebastião de Abreu et al. Eduardo Arrais Rocha Isadora Sucupira Machado Isabelle Oliveira Parahyba … Thaís de Brito Rocha Fernando José Villar Nogueira Paes Tereza Cristina Pinheiro Diogenes Marília Esther Benevides de Abreu Ana Gardenia Liberato Ponte Farias Marcia Maria Carneiro José Nogueira Paes Junior

Abstract

Background:

Normal coronary flow velocity reserve (CFVR) (≥ 2) obtained in the left anterior descending coronary artery (LAD) from transthoracic echocardiography is associated with a good prognosis, but there is no study correlating CFVR with submaximal target heart rate (HR).

Objective:

To evaluate the prognostic value of CFVR obtained in the LAD of patients with preserved (>50%) left ventricular ejection fraction (LVEF) who completed a dobutamine stress echocardiography (DSE), considering target HR.

Methods:

Prospective study of patients with preserved LVEF and CFVR obtained in the LAD who completed DSE. In Group I (GI = 31), normal CFVR was obtained before achieving target HR, and, in Group II (GII = 28), after that. Group III (G III=24) reached target HR, but CFVR was abnormal. Death, acute coronary insufficiency, coronary intervention, coronary angiography without further intervention, and hospitalization were considered events.

Results:

In 28 ± 4 months, there were 18 (21.6%) events: 6% (2/31) in GI, 18% (5/28) in GII, and 46% (11/24) in GIII. There were 4 (4.8%) deaths, 6 (7.2%) coronary interventions and 8 (9.6%) coronary angiographies without further intervention. In event-free survival by regression analysis, GIII had more events than GI (p < 0.001) and GII (p < 0.045), with no difference between GI and GII (p = 0.160). After adjustment, the only difference was between GIII and GI (p = 0.012).

Conclusion:

In patients with preserved LVEF and who completed their DSE, normal CFVR obtained before achieving target HR was associated with better prognosis.

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ABC

Original Article

Dobutamine Stress Echocardiography Safety in Chagas Disease Patients

Daniela do Carmo Rassi et al. Marcelo Luiz Campos Vieira Rogerio Gomes Furtado Fabio de Paula Turco … Luciano Henrique Melato Viviane Tiemi Hotta Colandy Godoy de Oliveira Nunes Luiz Rassi Jr. Salvador Rassi

Abstract

Background:

A few decades ago, patients with Chagas disease were predominantly rural workers, with a low risk profile for obstructive coronary artery disease (CAD). As urbanization has increased, they became exposed to the same risk factors for CAD of uninfected individuals. Dobutamine stress echocardiography (DSE) has proven to be an important tool in CAD diagnosis. Despite being a potentially arrhythmogenic method, it is safe for coronary patients without Chagas disease. For Chagas disease patients, however, the indication of DSE in clinical practice is uncertain, because of the arrhythmogenic potential of that heart disease.

Objectives:

To assess DSE safety in Chagas disease patients with clinical suspicion of CAD, as well as the incidence of arrhythmias and adverse events during the exam.

Methods:

Retrospective analysis of a database of patients referred for DSE from May/2012 to February/2015. This study assessed 205 consecutive patients with Chagas disease suspected of having CAD. All of them had their serology for Chagas disease confirmed.

Results:

Their mean age was 64±10 years and most patients were females (65.4%). No patient had significant adverse events, such as acute myocardial infarction, ventricular fibrillation, asystole, stroke, cardiac rupture and death. Regarding arrhythmias, ventricular extrasystoles occurred in 48% of patients, and non-sustained ventricular tachycardia in 7.3%.

Conclusion:

DSE proved to be safe in this population of Chagas disease patients, in which no potentially life-threatening outcome was found.

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Artigo Original

Clinical and echocardiographic parameters associated with low chronotropic index in non-elderly patients

Paulo Fernando Carvalho Secundo et al. Bruno Fernandes de Oliveira Santos José Alves Secundo Júnior Joiciane Bárbara da Silva … Adriana Ribeiro de Souza Gustavo Baptista de Almeida Faro José Augusto Barreto- Filho Antônio Carlos Sobral Sousa Joselina Luzia Menezes Oliveira

BACKGROUND: Despite abundant evidence of increased morbidity and mortality, chronotropic incompetence (CI) is not a routine diagnosis well defined in protocols of cardiac evaluation and its clinical importance is still underestimated. OBJECTIVE: To evaluate the clinical and echocardiographic parameters associated with HF in non-elderly patients submitted to stress echocardiography (SE). METHODS: One thousand seven hundred ninety-eight patients with a mean age of 48.4 ± 7.5 years, who underwent SE between January/2000 and August/2009 were evaluated. Patients with chronotropic index smaller than 0.8 were considered chronotropic incompetent as compared to competent patients as to clinical and echocardiographic characteristics. RESULTS: The duration of the exercise was 9.3 ± 2.4 minutes on average. Two hundred and seventy (15%) patients were chronotropic incompetent. The chronotropic index of this group was 0.7 ± 0.1 vs. 1.0 ± 0.1 for competent patients. Multivariate logistic regression analysis identified the following parameters as independently associated with HF: dyspnea on examination [odds ratio (OR) = 4.27, p <0.0001], previous chest pain on medical history (OR = 1.51; p = 0.0111), higher left ventricular mass rate in incompetent patients (LVMI) (OR = 1.16, p = 0.0001), metabolic equivalents (METs) (OR = 0.70, p = 0 , 0001), ST segment depression (OR = 0.58, p = 0.0003) and high systolic blood pressure (ΔSBP) (OR = 0.87, p = 0.0011). Myocardial ischemia was not associated with HF. CONCLUSION: HF is associated with functional parameters, such as dyspnea on exertion, history of chest pain and lower METS. It is also associated with structural benchmark index of left ventricular mass. In addition, chronotropic incompetence does not appear to increase the chance of myocardial ischemia in non-elderly patients. (Arq Bras Cardiol. 2012; [online].ahead print, PP.0-0)

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Artigo Original

Prognostic value of dipyridamole stress echocardiography in women

Maria Celita de Almeida et al. Brivaldo Markman Filho

BACKGROUND: Stress echocardiography is an important diagnostic and prognostic tool in ischemic heart disease. OBJECTIVE: To evaluate the role of dipyridamole stress echocardiography (DSE) in the investigation of myocardial ischemia in women and its ability to predict combined events (cardiovascular death, acute myocardial infarction [AMI], unstable angina, coronary artery bypass grafting [surgery or percutaneous intervention] at an average follow-up of 16 months. METHODS: A prospective study using the protocol of dipyridamole at 0.84 mg in 10 minutes, associated with atropine (0.25 mg/min up to 1.0 mg). RESULTS: This study evaluated 147 women. DSE was positive in 14 patients (9.5%), negative in 128 (87.1%) and inconclusive in 5 (3.4%). Events occurred in 8 patients, 7 had positive DSE. The other 138 did not present any events. Our of these, 128 had negative DSE. The sensitivity, specificity, accuracy, the positive and negative predictive values of the test before the events were respectively: 83%, 95%, 94%, 42% and 99%. The event-free survival for patients with negative DSE was 99.2% compared with 58% for positive DSE (p < 0.001). Univariate analysis identified the DSE result, basal electrocardiogram (ECG), LV ejection fraction, dyslipidemia, wall motion score index at rest and peak, history of AMI, coronary artery bypass grafting, as prognostic predictors related to outcomes. The results of DSE and ECG remained significantly associated with outcomes in the multivariate analysis (p < 0.001). CONCLUSION: The baseline ECG and positive DSE were independent variables for the occurrence of outcomes. The DSE showed excellent negative predictive value, confirming its usefulness in evaluating prognosis in such patients.

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Artigo Original

Dobutamine-stress echocardiography in asymptomatic patients with aortic regurgitation

Marcia M. Barbosa et al. Claudia M. V. Freire Lúcia M. A. Fenelon William A. M. Esteves … Gilmar Reis Maria do Carmo P. Nunes

BACKGROUND: Decreased contractile reserve may already be present in asymptomatic patients with aortic regurgitation and normal ejection fraction (EF), thus indicating the need for frequent and accurate assessments of the left ventricular function for the early detection of systolic dysfunction. OBJECTIVE: To analyze if increments in EF with low dose dobutamine could predict surgery and/or death in patients with aortic regurgitation. METHDOS: Dobutamine-stress echocardiography was performed in 24 patients with aortic regurgitation in order to analyze whether EF increments at low dobutamine doses could predict the need for surgery and/or death in this group of patients. RESULTS: Mean age was 37.8±16.8 years and 16 patients (66%) were male. EF increased from a mean baseline value of 62.3±7.9% to 71.5±10.5% at a dobutamine dose of 20 µg/kg/min (p<0.001). The patients were followed-up for 36.6±20.1 months; two patients died (one of cardiovascular death) and five underwent cardiac surgery. Baseline EF was correlated with surgery and death in the follow-up of patients. CONCLUSION: Baseline EF was correlated with surgery or death in the follow-up of young patients with aortic regurgitation. However, the percentage increase in EF at low dobutamine doses did not allow us to predict events in these patients.

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Case Report

Dobutamine stress echocardiography-induced broken heart syndrome (Takotsubo Syndrome)

Francisco Juarez Cruz de Vasconcelos Filho et al. Cezario Antonio Martins Gomes Oscar Aires de Queiroz José Erirtonio Façanha Barreto

We report a case of dobutamine stress echocardiography-induced Takotsubo syndrome in a 76-year-old hypertensive patient with clinical complaints of chest pain in an elective visit to the cardiologist. Dobutamine-stress-echocardiography was requested to rule out chest pain of coronary origin. During the test, at peak exercise, echocardiogram showed apical akinesia and electrocardiogram showed ST-segment elevation in D1, AVL, and V2. The patient was hospitalized and underwent coronary angiography, which showed normal coronary arteries and left ventricular apical ballooning. During follow-up, the patient’s condition remained stable, with regression of the manifestations 21 days after the initial presentation.

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Artigo Original

Exercise stress echocardiography in the identification of coronary artery disease in the elderly with chronotropic incompetence

Joselina Luzia Menezes Oliveira et al. Thiago Jônatas Santos Góes Thaiana Aragão Santana Isabela Souza Silva … Thiago Figueiredo Travassos Lívia Dantas Teles Martha Azevedo Barreto José Augusto Barreto-Filho Argemiro D'Oliveira Junior Antonio Carlos Sobral Sousa

BACKGROUND: Chronotropic incompetence (CTI) is frequent in elderly patients and may limit the role of the exercise test in the identification of coronary artery disease (CAD) in this population. OBJECTIVE: To assess the value of CTI in an elderly population in the diagnosis of CAD. METHODS: A total of 3,308 patients were studied, 804 were elderly individuals (age > 65 years) who underwent exercise stress echocardiography (ESE). Based on the heart rate (HR) reached during the exercise test, were divided into two groups: G1 150 patients who did not reach 85% of the age-predicted HR, and G2 654 patients who did. The groups were compared to clinical characteristics, segmental left ventricular contractility rate (WMSI) and coronary angiography (CAG). RESULTS: Clinical characteristics were similar between the groups. WMSI was higher in G1 than in G2, both at rest (1.09 ± 0.21 versus 1.04 ± 0.15) and after exercise (1.15 ± 0.29 versus 1.08 ± 0.2) (p < 0.001). Abnormalities in wall contractility were more frequent in G1 than in G2 (55% versus 37%; p 50%). CONCLUSION: CTI is associated with a higher frequency of contractile alterations in the elderly population and adds a positive predictive value to ESE in the identification of patients with obstructive CAD.

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