Apparent Declining Prognostic Value of a Negative Stress Echocardiography Based on Regional Wall Motion Abnormalities in Patients With Normal Resting Left Ventricular Function Due to the Changing Referral Profile of the Population Under Study.

Background Cardiology guidelines identify the low-risk response during stress echocardiography as the absence of regional wall motion abnormalities. Methods From 1983 to 2016, we enrolled 5817 patients (age 63±12 years; 2830 males) with suspected coronary artery disease, normal regional, and global left ventricular function at rest and during stress (exercise in 692, dipyridamole in 4291, and dobutamine in 834). Based on timing of enrollment, 4 groups were identified in chronological order of recruitment: years 1983 to 1989, group 1 (n=211); years 1990 to 1999, group 2 (n=1491); years 2000 to 2009, group 3 (n=3285); and years 2010 to 2016, group 4 (n=830). Results There were 240 (4%) events (119 deaths and 121 infarctions) in the follow-up. At 1-year follow-up, the event rate was 0.5% (95% CI, 0.05-0.95), 1.5% (95% CI, -1.18 to 1.82), 1.9% (95% CI, 1.63-2.17), and 1.7% (95% CI, 1.01-2.39; χ2, 9.0; P=0.03) in groups 1 to 4, respectively. At multivariable Cox analysis, independent predictors of future events were age (hazard ratio (HR), 1.05; 95% CI, 1.04-1.07; P<0.0001), male sex (HR, 1.57; 95% CI, 1.20-2.04; P=0.001), diabetes mellitus (HR, 1.78; 95% CI, 1.34-2.37; P<0.0001), smoking habit (HR, 1.40; 95% CI, 1.05-1.85; P=0.02), and ongoing anti-ischemic therapy (HR, 1.50; 95% CI, 1.15-1.97; P=0.003) Conclusions Over the past 3 decades, we observed a progressive decline in the prognostic value of a negative test based on regional wall motion abnormalities, likely reflecting both an increase in risk in patients, as well as a potential decrease in test performance due to concomitant anti-ischemic therapy.

Electrocardiographic exercise testing in adults: performance and interpretation. An expert opinion of the Polish Cardiac Society Working Group on Cardiac Rehabilitation and Exercise Physiology.

Electrocardiographic (ECG) exercise stress test has been a major diagnostic test in cardiology for several decades. Ongoing technological advances that have led to a wide use of imaging techniques and development of new guidelines have called for a revised and updated approach to the technique and interpretation of the ECG exercise testing. The present document outlines an expert opinion of the Polish Cardiac Society Working Group on Cardiac Rehabilitation and Exercise Physiology regarding the performance and interpretation of ECG exercise testing in adults. We discussed technical requirements and necessary equipment for the exercise testing laboratory as well as healthcare personnel competencies necessary to supervise ECG exercise testing and fully interpret test findings. Broad indications for ECG exercise testing include diagnostic assessment of coronary artery disease (CAD), including pre-test probability of CAD, evaluation of functional disease severity and risk strati- fication in patients with established CAD, assessment of response to treatment, evaluation of exercise-related symptoms and exercise capacity, patient evaluation before exercise training/cardiac rehabilitation, and risk stratification prior to non-cardiac surgery. ECG exercise testing is safe if indications and contraindications are observed, testing is appropriately monitored, and indications for test termination are clearly established. The exercise protocol should be adjusted to the expected exercise capacity of a patient so as to limit the duration of exercise to 8-12 min. Clinical, haemodynamic, and ECG response to exercise is evaluated during the test. The test report should include information about the exercise protocol used, reason for test termination, perceived exertion, presence/severity of anginal symptoms, peak exercise capacity or tolerated workload in relation to the predicted exercise capacity, heart rate response, and the presence or absence of ST-T changes. The test report should conclude with a summary including clinical and ECG assessment.

Development of an Educational Strategy and Decision Support Tool to Enhance Appropriate Use of Stress Echocardiography at a Large Academic Medical Center: A Prospective, Pre- and Postintervention Analysis.

BACKGROUND: Despite previous studies demonstrating suboptimal appropriate use of stress echocardiography (SE), few interventions have been demonstrated to improve its appropriate use. The aim of this study was to develop a novel mechanism to improve the appropriateness of SE by implementing a point-of-care decision support tool and ordering requisition coupled with an educational strategy. METHODS: A prospective pre- and postintervention analysis was conducted. The intervention included education and the development and implementation of novel ordering requisition coupled with a decision support tool that integrated appropriate use criteria (AUC) for SE. RESULTS: In the baseline period, 256 consecutive stress echocardiographic studies were evaluated, and 97% were classifiable by the 2011 AUC. During the intervention period, 159 studies were evaluated (98% classifiable). The intervention resulted in an increase in the appropriate proportion from 65% to 76% and a reduction in the rarely appropriate proportion from 31% to 19% (P = .017). After adjustment for physician specialty, the postintervention period had lower odds of rarely appropriate testing (0.54; 95% CI, 0.3-0.95; P = .04). Cardiology had significant lower odds of rarely appropriate testing (0.23; 95% CI, 0.11-0.50; P < .001) compared with family practice (the reference standard). Vascular surgery had the highest odds (5.76; 95% CI, 2.18-21.52; P = .002) of rarely appropriate testing. CONCLUSION: AUC have not previously been applied to SE in a single-payer, publicly funded health system. The development of an educational intervention involving a new requisition and decision support tool that integrated AUC resulted in a significantly reduced proportion of rarely appropriate SE. Cardiologists ordered the highest proportion of appropriate SE. Further study is needed to determine the generalizability of the results.

Exercise testing in asymptomatic severe aortic stenosis.

The management and the clinical decision making in asymptomatic patients with aortic stenosis are challenging. An "aggressive" management, including early aortic valve replacement, is debated in these patients. However, the optimal timing for surgery remains controversial due to the lack of prospective data on the determinants of aortic stenosis progression, multicenter studies on risk stratification, and randomized studies on patient management. Exercise stress testing with or without imaging is strictly contraindicated in symptomatic patients with severe aortic stenosis. Exercise stress test is now recommended by current guidelines in asymptomatic patients and may provide incremental prognostic value. Indeed, the development of symptoms during exercise or an abnormal blood pressure response are associated with poor outcome and should be considered as an indication for surgery, as suggested by the most recently updated European Society of Cardiology 2012 guidelines. Exercise stress echocardiography may also improve the risk stratification and identify asymptomatic patients at higher risk of a cardiac event. When the test is combined with imaging, echocardiography during exercise should be recommended rather than post-exercise echocardiography. During exercise, an increase >18 to 20 mm Hg in mean pressure gradient, absence of improvement in left ventricular ejection fraction (i.e., absence of contractile reserve), and/or a systolic pulmonary arterial pressure >60 mm Hg (i.e., exercise pulmonary hypertension) are suggestive signs of advanced stages of the disease and impaired prognosis. Hence, exercise stress test may identify resting asymptomatic patients who develop exercise abnormalities and in whom surgery is recommended according to current guidelines. Exercise stress echocardiography may further unmask a subset of asymptomatic patients (i.e., without exercise stress test abnormalities) who are at high risk of reduced cardiac event free survival. In these patients, early surgery could be beneficial, whereas regular follow-up seems more appropriate in patients without echocardiographic abnormalities during exercise.

International RCT-based guidelines for use of preoperative stress testing and perioperative beta-blockers and statins in non-cardiac surgery.

BACKGROUND: Cardiologists frequently advise on perioperative care for non-cardiac surgery and require guidance based on randomised controlled trials that are not discredited by misconduct or misreporting. Regional political bodies currently do not provide this. We therefore examined the credible randomised controlled trial (RCT) evidence on key cardiac perioperative questions which currently have 14 recommendations. METHODS: Three aspects of perioperative measures were considered: perioperative statins, preoperative stress-testing and perioperative beta-blockade. One author searched PubMed for RCTs considering these topics. All authors independently assessed the RCTs and then collaboratively composed guidelines. RESULTS: Perioperative statin therapy has been examined by three RCTs, DECREASE III and IV, which are discredited and a third containing serious inconsistencies undermining its validity. Preoperative stress testing has been examined by two RCTs: one discredited trial, DECREASE II, and a second which found no benefit. Perioperative beta-blockade has been examined by eleven RCTs, two of which are discredited. The nine remaining trials together suggest that perioperative beta-blockade increases mortality. CONCLUSIONS: When the non-credible RCTs are omitted, the evidence base on these three subjects is much smaller than previously believed: 14 recommendations can be replaced by 3. Current guideline arrangements collectively paralyse the numerous signatories from making urgent amendments after initial publication, even when important new information comes to light. Clinicians simply have to wait for the routine five-year expiry. We present a concise scientifically based guideline and commit to updating it responsibly.

Feasibility, safety and accuracy of regadenoson-atropine (REGAT) stress echocardiography for the diagnosis of coronary artery disease: an angiographic correlative study.

Regadenoson (REG), a selective A2A receptor vasodilator, has not been widely evaluated in stress echocardiography (SE). We report results of 45 patients participating in REG + atropine (REGAT) SE protocol conducted in a single-center prospective trial. The REGAT study enrolled subjects before a clinically indicated cardiac catheterization for suspected coronary artery disease (CAD). After rest imaging, a 2 mg Atropine (AT) bolus followed by 400 mcg of REG was given. Standard stress imaging views were obtained and interpreted in blinded fashion. Sensitivity, specificity, positive and negative predictive values (PPV, NPV) were calculated using cardiac catheterization >70 % stenosis as gold standard. Additional endpoints included major adverse cardiac events (MACE) and patient questionnaire responses. The mean duration of REGAT was 18 ± 7.2 min. There were no MACE, with only transient side-effects of dry mouth, shortness of breath, and headache. The incidence of significant CAD was 51.1 %. The sensitivity and specificity for significant stenosis was 60.9 and 86.4 %, with a PPV and NPV of 82.4 and 67.9 %. By coronary territories, the sensitivity, specificity, PPV, and NPV were: left anterior descending artery 58.8, 92.9, 83.3, and 78.8 %; left circumflex artery 6.7, 93.3, 33.3, and 67.7 %; and right coronary artery 16.7, 93.9, 50, and 75.6 %. Over 90 % of subjects reported feeling comfortable, with 83 % preferring REGAT as a future stress modality. The REGAT protocol is fast, safe, and well-tolerated with good specificity for CAD detection, but its low sensitivity and NPV precludes it from being an imaging modality for routine use.

High numbers of false-positive stress tests are the result of inappropriate testing.

Patients who underwent coronary angiography preceded by stress testing during the period January 2009 through March 2012 were evaluated using the CathPCI database. The predictive accuracy of stress echocardiography (SE) and single-photon emission computed tomography (SPECT) were determined and used to back calculate the pretest probability of the population being tested. In total, 2662 catheterizations were performed, 866 (33%) of which were preceded by stress imaging. Overall, the positive predictive values of SE and SPECT did not differ significantly (61% and 66%, P = .15) and were much lower in certain subgroups. The overall pretest probabilities of patients without a documented history of coronary artery disease undergoing SE and SPECT in the study population were estimated to be 18% and 27%, respectively. This study shows that stress testing is performed too often in low-risk patients in whom it is unlikely to improve clinical decision making.

Appropriate use criteria for stress echocardiography: impact of updated criteria on appropriateness ratings, correlation with pre-authorization guidelines, and effect of temporal trends and an educational initiative on utilization.

OBJECTIVES: This study evaluated utilization of stress echocardiography (SE) at our institution, the impact of the updated 2011 appropriate use criteria (AUC) on appropriateness ratings, correlation of AUC to radiology benefits managers' (RBM) pre-certification guidelines and the effect of temporal trends and an AUC-based educational project on appropriateness. BACKGROUND: The AUC for SE have been developed to improve efficiency of utilization and promote optimal patient care. METHODS: We classified the appropriateness of 209 SEs from 2008 using the original and updated AUC. We also performed pre-authorization determinations on these SEs using the guidelines of 2 RBMs. We then classified and compared the appropriateness of 209 SEs from 2011 using the updated criteria to that of the 2008 cohort. Finally, we rated and compared 111 SEs requested by cardiologists after an educational project to 111 SEs referred before the intervention. RESULTS: Overall, nearly one-third of SEs were requested for inappropriate indications. Using 2011 AUC, the original ratings of 52 (25%) studies by AUC 2008 were changed and the number of unclassified SE decreased from 20 (9.6%) to 2 (1%). Correlation between RBM pre-authorization determination and AUC ratings was substantial for the first RBM (κ = 0.625) and fair for the second (κ = 0.358). However, 12.9% and 41.9% of studies classified as appropriate or uncertain by the AUC would not have received pre-authorization according to the guidelines of the first and second RBMs, respectively. Referrals of inappropriate SE did not decrease over time or with an educational intervention. CONCLUSIONS: The revisions in the updated AUC improve their clinical application by encompassing nearly all indications for SE. The limited correlation between AUC ratings and RBM determinations suggests a need for greater consistency. The large number of SE requested for inappropriate indications at our institution did not decrease with time or education.

ACR Appropriateness Criteria® chronic chest pain--high probability of coronary artery disease.

Imaging is valuable in determining the presence, extent, and severity of myocardial ischemia and the severity of obstructive coronary lesions in patients with chronic chest pain in the setting of high probability of coronary artery disease. Imaging is critical for defining patients best suited for medical therapy or intervention, and findings can be used to predict long-term prognosis and the likely benefit from various therapeutic options. Chest radiography, radionuclide single photon-emission CT, radionuclide ventriculography, and conventional coronary angiography are the imaging modalities historically used in evaluating suspected chronic myocardial ischemia. Stress echocardiography, PET, cardiac MRI, and multidetector cardiac CT have all been more recently shown to be valuable in the evaluation of ischemic heart disease. Other imaging techniques may be helpful in those patients who do not present with signs classic for angina pectoris or in those patients who do not respond as expected to standard management. The ACR Appropriateness Criteria(®) are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

Evaluation of the clinical application of the ACCF/ASE appropriateness criteria for stress echocardiography.

BACKGROUND: The aim of this study was to evaluate the clinical application of the American College of Cardiology Foundation and American Society of Echocardiography appropriateness criteria for stress echocardiography (SE) in a single-center university hospital. METHODS: Indications were determined for consecutive studies by two reviewers and categorized as appropriate, uncertain, or inappropriate. RESULTS: Of 477 studies for which primary indications could be determined, 188 specifically related to university transplantation programs were excluded. Of the remaining 289 studies, 88% were addressed in the appropriateness criteria for SE. Of these, 71% were appropriate, 9% were uncertain, and 20% were inappropriate. Inappropriate studies were more likely to be ordered on younger patients and women and were less likely to be ordered by cardiologists. Abnormal results on SE were more frequent among appropriate than inappropriate studies. CONCLUSIONS: The appropriateness criteria for SE encompass and effectively characterize the majority of studies ordered in a single-center university hospital and appear to reasonably stratify the likelihood of abnormal results on SE. However, revisions will be required to fully capture and stratify appropriate clinical practice of SE.

Internal thoracic artery graft (ITAG): patency and functional status at rest and during dobutamine-stress echocardiography.

BACKGROUND: The patent internal thoracic artery graft (ITAG) usually has a diastolic fraction (DF) > 50% of the flow. The functional assessment can be evaluated by the coronary reserve index (CRI). OBJECTIVE: The objective was to evaluate the patency and functional status of the ITAG through echocardiography and Doppler. METHODS: Data from sixty-six patients who underwent dobutamine-stress echocardiography (DSE) were prospectively collected and analyzed. Group I (GI) had 49 ITAG without stenosis, Group II (GII), 10 ITAG with significant stenosis (> 50% and <100%) and Group III (GIII) had 7 ITAG with total occlusion. Diameters and Doppler spectrums from the ITAG at rest and during DSE were evaluated. RESULTS: Considering patency a DF >50%, it was observed in 49 ITAG (GI= 40, GII= 8 and GIII= 1) at rest and in 61 ITAG (GI=49, GII=10 and GIII=2) during DSE. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy were respectively, 81%, 86%, 98%, 35% and 82%, and 100%, at rest and 71%, 97%, 100% and 97% in the DSE. The ITAG with DF>50% at rest were patent and the ones with DF<50% in the DSE presented total occlusion. Considering a CRI>1.8 for a good functional status, it was observed in 42 ITAG (39 from GI, 2 from GII and 1 from GIII), determining sensitivity=79%, specificity=85.7%, PPV=94%, NPV=59% and accuracy= 80.9%. The CRI in GI was higher (p= 0.02) than in GII or GIII. CONCLUSION: In our study, the non-invasive assessment of the ITAG was effective to verify the patency and the functional status.

ACCF/ASE/ACEP/AHA/ASNC/SCAI/SCCT/SCMR 2008 appropriateness criteria for stress echocardiography: a report of the American College of Cardiology Foundation Appropriateness Criteria Task Force, American Society of Echocardiography, American College of Emergency Physicians, American Heart Association, American Society of Nuclear Cardiology, Society for Cardiovascular Angiography and Interventions, Society of Cardiovascular Computed Tomography, and Society for Cardiovascular Magnetic Resonance: endorsed by the Heart Rhythm Society and the Society of Critical Care Medicine.

The American College of Cardiology Foundation (ACCF) and the American Society of Echocardiography (ASE) together with key specialty and subspecialty societies, conducted an appropriateness review for stress echocardiography. The review assessed the risks and benefits of stress echocardiography for several indications or clinical scenarios and scored them on a scale of 1 to 9 (based upon methodology developed by the ACCF to assess imaging appropriateness). The upper range (7 to 9) implies that the test is generally acceptable and is a reasonable approach, and the lower range (1 to 3) implies that the test is generally not acceptable and is not a reasonable approach. The midrange (4 to 6) indicates a clinical scenario for which the indication for a stress echocardiogram is uncertain. The indications for this review were drawn from common applications or anticipated uses, as well as from current clinical practice guidelines. Use of stress echocardiography for risk assessment in patients with coronary artery disease (CAD) was viewed favorably, while routine repeat testing and general screening in certain clinical scenarios were viewed less favorably. It is anticipated that these results will have a significant impact on physician decision making and performance, reimbursement policy, and will help guide future research.

ACCF/ASE/ACEP/AHA/ASNC/SCAI/SCCT/SCMR 2008 appropriateness criteria for stress echocardiography: a report of the American College of Cardiology Foundation Appropriateness Criteria Task Force, American Society of Echocardiography, American College of Emergency Physicians, American Heart Association, American Society of Nuclear Cardiology, Society for Cardiovascular Angiography and Interventions, Society of Cardiovascular Computed Tomography, and Society for Cardiovascular Magnetic Resonance endorsed by the Heart Rhythm Society and the Society of Critical Care Medicine.

The American College of Cardiology Foundation (ACCF) and the American Society of Echocardiography (ASE) together with key specialty and subspecialty societies, conducted an appropriateness review for stress echocardiography. The review assessed the risks and benefits of stress echocardiography for several indications or clinical scenarios and scored them on a scale of 1 to 9 (based upon methodology developed by the ACCF to assess imaging appropriateness). The upper range (7 to 9) implies that the test is generally acceptable and is a reasonable approach, and the lower range (1 to 3) implies that the test is generally not acceptable and is not a reasonable approach. The midrange (4 to 6) indicates a clinical scenario for which the indication for a stress echocardiogram is uncertain. The indications for this review were drawn from common applications or anticipated uses, as well as from current clinical practice guidelines. Use of stress echocardiography for risk assessment in patients with coronary artery disease (CAD) was viewed favorably, while routine repeat testing and general screening in certain clinical scenarios were viewed less favorably. It is anticipated that these results will have a significant impact on physician decision making and performance, reimbursement policy, and will help guide future research.

[Cardiac imaging in suspected coronary artery disease]. / Kardiale Bildgebung bei Verdacht auf eine koronare Herzkrankheit.

Within the scope of this review, non-invasive imaging modalities applicable for further work-up of suspected coronary artery disease (CAD) are discussed with regard to methodology, diagnostic accuracy and prognostic value. All of these imaging modalities can be employed in patients with an intermediate pretest probability of disease, if ECG stress testing is either not reasonable, not possible due to physical limitations or if the result is inconclusive. Stress echocardiography is a cost-effective and an easily practicable method based on the indirect detection of myocardial ischemia by visually assessing provoked wall motion abnormalities. Therefore, its diagnostic value is mainly determined by individual expertise. In case of myocardial scintigraphy, reduced myocardial perfusion causes signal intensity differences in SPECT images following physical or pharmacological stress which are reversible at rest. Myocardial scintigraphy is characterised by a high negative predictive value at the expense of a lower specificity due to false positive results based on methodological limitations. Cardiovascular magnetic resonance imaging (CMR) offers a comprehensive cardiac study in a single procedure. Apart from detecting myocardial ischemia by dobutamine-stress-CMR or adenosine-perfusion-CMR, it enables the precise detection of even small areas of myocardial infarction on contrast-enhanced images. In spite of fascinating high-resolution coronary images, multi-detector computed tomography (MDCT) has hardly been included in current guidelines due to the unavoidable risks of radiation and contrast medium exposure and the current uncertainty in defining appropriate clinical indications. However, quantification of coronary calcium is easily performed and may be useful for prognostic assessment in patients with intermediate risk profile.

Internal thoracic artery graft (ITAG): patency and functional status at rest and during dobutamine-stress echocardiography / Artéria torácica interna enxertada: patência e estado funcional em repouso e após dobutamina

FUNDAMENTO: A artéria torácica interna enxertada (ATIE) patente usualmente tem fração diastólica (FD)> 50 por cento do fluxo. O estado funcional pode ser avaliado pelo índice de reserva coronariano (IRC). OBJETIVO: Avaliar, pela ecocardiografia e pelo Doppler em nível supraclavicular, a patência e o estado funcional da ATIE. MÉTODOS: Foram coletados prospectivamente e analisados os dados de 66 pacientes submetidos a ecocardiograma sob estresse com dobutamina (EED). O grupo I (GI) ocorreu com 49 ATIE sem estenose. No grupo II (GII) (10 ATIE) havia estenose significativa (> 50 por cento e <100 por cento). E no grupo III (GIII) (7 ATIE) a oclusão era de 100 por cento. Foram avaliados diâmetros e espectros do Doppler das ATIE no repouso e EED. RESULTADOS: Considerando patência uma FD>50 por cento, ocorreu em 49 ATIE (GI=40, GII=8 e GIII=1) no repouso e em 61 ATIE (GI=49, GII=10 e GIII=2) durante EED. Sensibilidade, especificidade, valor preditivo positivo (VPP), valor preditivo negativo (VPN) e acurácia foram, respectivamente, em repouso, 81 por cento, 86 por cento ,98 por cento, 35 por cento e 82 por cento; e no EED, 100 por cento, 71 por cento, 97 por cento, 100 por cento e 97 por cento. As ATIE com FD>50 por cento em repouso estavam patentes e as com FD<50 por cento no EED tinham oclusão total. Considerando para bom estado funcional um IRC>1,8, isso ocorreu em 42 ATIE (39 do GI, 2 do GII e 1 GIII), verificando-se sensibilidade = 79 por cento; especificidade = 85,7 por cento; VPP = 94 por cento; VPN = 59 por cento; e acurácia = 80,9 por cento. O IRC no GI foi maior (p=0,02) que em GII e GIII. CONCLUSÃO: Em nosso estudo, a avaliação não-invasiva da ATIE foi efetiva para verificar patência e estado funcional.

BACKGROUND: The patent internal thoracic artery graft (ITAG) usually has a diastolic fraction (DF) > 50 percent of the flow. The functional assessment can be evaluated by the coronary reserve index (CRI). OBJECTIVE: The objective was to evaluate the patency and functional status of the ITAG through echocardiography and Doppler. METHODS: Data from sixty-six patients who underwent dobutamine-stress echocardiography (DSE) were prospectively collected and analyzed. Group I (GI) had 49 ITAG without stenosis, Group II (GII), 10 ITAG with significant stenosis (> 50 percent and <100 percent) and Group III (GIII) had 7 ITAG with total occlusion. Diameters and Doppler spectrums from the ITAG at rest and during DSE were evaluated. RESULTS: Considering patency a DF >50 percent, it was observed in 49 ITAG (GI= 40, GII= 8 and GIII= 1) at rest and in 61 ITAG (GI=49, GII=10 and GIII=2) during DSE. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy were respectively, 81 percent, 86 percent, 98 percent, 35 percent and 82 percent, and 100 percent, at rest and 71 percent, 97 percent, 100 percent and 97 percent in the DSE. The ITAG with DF>50 percent at rest were patent and the ones with DF<50 percent in the DSE presented total occlusion. Considering a CRI>1.8 for a good functional status, it was observed in 42 ITAG (39 from GI, 2 from GII and 1 from GIII), determining sensitivity=79 percent, specificity=85.7 percent, PPV=94 percent, NPV=59 percent and accuracy= 80.9 percent. The CRI in GI was higher (p= 0.02) than in GII or GIII. CONCLUSION: In our study, the non-invasive assessment of the ITAG was effective to verify the patency and the functional status.

Low-gradient aortic valve stenosis: value and limitations of dobutamine stress testing.

Aortic valve stenosis has already reached endemic proportions in Western countries. As the prognosis of low-flow aortic valve stenosis under medical treatment is dismal, surgery is recommended in most patients. Preoperative dobutamine stress testing may help to assess surgical risk, but there is no strong scientific evidence to deny surgery based exclusively on the results of this test. The problems associated with clinical decision making in this condition are reviewed.

Viabilidade miocárdica na lesão uniarterial: papel da ecocardiografia de estresse com dobutamina / Myocardial viability in a single-vessel disease: the role of a dobutamine stress echocardiography

OBJETIVO: Estudar um grupo de pacientes com lesão significativa em apenas uma artéria coronária e demonstrar se a ecocardiografia de estresse com dobutamina (EED) tem boa sensibilidade e especificidade na avaliação de viabilidade miocárdica nesse grupo de pacientes. MÉTODOS: Foram estudados 20 pacientes submetidos a angioplastia coronariana transluminal percutânea (ATC). Esse grupo foi avaliado 2 a 7 (3,65 ± 1,69) dias antes do procedimento, e 2 a 5 (4 ± 0,80) dias depois, realizando-se EED. Para a determinação de viabilidade miocárdica foi utilizado ecocardiograma bidimensional três meses após o procedimento. Doze pacientes foram submetidos a ATC de artéria descendente anterior (DA), 7 de artéria coronária direita (CD) e 1 de circunflexa (CX). Apenas um procedimento (CD) não obteve pleno êxito. RESULTADOS: Dos 340 segmentos estudados, 99 (29,18 por cento) demonstraram alterações contráteis, sendo 63 hipocinéticos (63,4 por cento), 28 acinéticos (28,28 por cento) e 8 discinéticos (8,08 por cento). Quanto aos segmentos envolvidos, obtivemos sensibilidade de 92,59 por cento, especificidade de 84,45 por cento, acurácia de 88,88 por cento para o exame EED. O único caso de ATC de CX demonstrou sensibilidade de 100 por cento; para DA, sensibilidade de 88,58 por cento, especificidade de 95 por cento e acurácia de 90,91 por cento. Para segmentos da CD, sensibilidade de 91,30 por cento, especificidade de 83,33 por cento e acurácia de 88,71 por cento. Todos os segmentos discinéticos eram inviáveis. Dos 63 hipocinéticos, a EED previu recuperação em 91,48 por cento. CONCLUSÃO: A EED é útil na avaliação de viabilidade miocárdica em pacientes com lesão significativa de apenas uma artéria.