Safety and Predictors of Complications with a New Accelerated Dobutamine Stress Echocardiography Protocol

Complications of exercise and pharmacologic stress echocardiography

Stress echocardiography is a diagnostic cardiovascular exam that is commonly utilized for multiple indications, including but not limited to the assessment of obstructive coronary artery disease, valvular disease, obstructive hypertrophic cardiomyopathy, and diastolic function. Stress echocardiography can be performed via both exercise and pharmacologic modalities. Exercise stress is performed with either treadmill or bicycle-based exercise. Pharmacologic stress is performed via either dobutamine or vasodilator-mediated (i.e., dipyridamole, adenosine) stress testing. Each of these modalities is associated with a low overall prevalence of major, life-threatening adverse outcomes, though adverse events are most common with dobutamine stress echocardiography. In light of the recent COVID-19 pandemic, the risk of infectious complications to both the patient and stress personnel cannot be negated; however, when certain precautions are taken, the risk of infectious complications appears minimal. In this article, we review each of the stress echocardiographic modalities, examine major potential adverse outcomes and contraindications, assess the risks of stress testing in the setting of a global pandemic, and examine the utilization and safety of stress testing in special patient populations (i.e., language barriers, pediatric patients, pregnancy).

Rationale and design of SAVI-AoS: A physiologic study of patients with symptomatic moderate aortic valve stenosis and preserved left ventricular ejection fraction

Background

Moderate aortic valve stenosis occurs twice as often as severe aortic stenosis (AS) and carries a similarly poor prognosis. Current European and American guidelines offer limited insight into moderate AS (MAS) patients with unexplained symptoms. Measuring valve physiology at rest while most patients experience symptoms during exertion might represent a conceptual limitation in the current grading of AS severity. The stress aortic valve index (SAVI) may delineate hemodynamically significant AS among patients with MAS.

Objectives

To investigate the diagnostic value of SAVI in symptomatic MAS patients with normal left ventricular ejection fraction (LVEF ≥ 50%): aortic valve area (AVA) > 1 cm² plus either mean valve gradient (MG) 15–39 mmHg or maximal aortic valve velocity (AOV max) 2.5–3.9 m/s. Short-term objectives include associations with symptom burden, functional capacity, and cardiac biomarkers. Long-term objectives include clinical outcomes.

Methods and results

Multicenter, non-blinded, observational cohort. AS severity will be graded invasively (aortic valve pressure measurements with dobutamine stress testing for SAVI) and non-invasively (echocardiography during dobutamine and exercise stress). Computed tomography (CT) of the aortic valve will be scored for calcium, and hemodynamics simulated using computational fluid dynamics. Cardiac biomarkers and functional parameters will be serially monitored. The primary objective is to see how SAVI and conventional measures (MG, AVA and Vmax) correlate with clinical parameters (quality of life survey, 6-minute walk test [6MWT], and biomarkers).

Conclusions

The SAVI-AoS study will extensively evaluate patients with unexplained, symptomatic MAS to determine any added value of SAVI versus traditional, resting valve parameters.

High-Dose Dobutamine for Inducibility of Atrial Arrhythmias During Atrial Fibrillation Ablation

OBJECTIVES

This study sought to compare the effect of high-dose dobutamine (DBT) with that of high-dose isoproterenol (IPN) in eliciting triggers during atrial fibrillation (AF) ablation.

BACKGROUND

High-dose IPN is commonly used to elicit triggers during AF ablation. However, it is not available worldwide and, in the United States, its cost per dose has significantly increased. DBT is a similarly nonselective β-agonist and, as such, is a potential alternative.

METHODS

This was a prospective, randomized 2×2 crossover study of patients undergoing AF ablation. Patients were assigned to receive IPN (20 to 30 μg/min for 10 min) followed by DBT (40 to 50 μg/kg/min for 10 min) or vice versa in a 1:1 fashion. The type, number, and location of triggers as well as heart rate, blood pressure, and side effects were noted.

RESULTS

Fifty patients were included in the study. Both drugs caused a significant increase in heart rate, with a consistently lower peak for DBT. Blood pressure significantly increased with DBT, while there was a significant reduction with IPN, despite phenylephrine support. Atrial arrhythmias induced during DBT were comparable to that induced during IPN. In patients with IPN-inducible outflow tract premature ventricular contractions, a similar effect was noted with DBT. No major complications occurred during either drug challenge.

CONCLUSIONS

High-dose DBT is safe and comparable to high-dose IPN in respect of eliciting AF triggers, with the advantage to maintain systemic pressure without the need of additional vasopressor support. This study supports the use of high-dose DBT in electrophysiology laboratories in which IPN is not readily available and for those patients in whom hypotension is a concern.

Frequency of hypertensive response to dobutamine stress and diminished diagnostic value in patients with end-stage renal disease awaiting renal transplant

BACKGROUND

Patients with end-stage renal disease (ESRD) have a cardiovascular mortality about 15-30 times the general population and this is reduced by about 70% with renal transplant. Dobutamine stress echocardiography (DSE) is commonly performed for preoperative cardiac evaluation before renal transplantation. Hypertensive response during DSE occurs in about 1%-5% of DSE studies. However, it seems to be more frequent in patients with ESRD. But its frequency and clinical implications are not known.

METHODS AND RESULTS

Of the 249-consecutive adult ESRD patients undergoing DSE for pre-kidney transplant cardiac risk assessment at our dedicated clinic, 53 (21%) had a hypertensive response. Half of the patients with a hypertensive response had stress-induced segmental wall motion abnormalities, of whom only half had angiographically significant coronary artery disease by quantitative coronary angiography. The hypertensive response was not a predictor of survival. Stress-induced segmental wall motion abnormalities predicted poor survival in those with a normotensive response, but not in those with a hypertensive response. The main and independent predictor of a hypertensive response was higher baseline systolic blood pressure (P < .0001).

CONCLUSIONS

Hypertensive response to dobutamine stress is common in ESRD patients and is not a predictor of survival. Stress-induced segmental wall motion abnormalities occur nearly thrice as frequently with a hypertensive response, but this is a poor predictor of angiographically significant coronary artery disease and does not predict survival.

Incidence and variables associated with arrhythmias during dobutamine-atropine stress echocardiography among patients with Chagas disease

BACKGROUND

Dobutamine stress echocardiography (DSE) is an important tool in the diagnosis of coronary artery disease. However, there is hesitation in clinical practice for using it in patients with Chagas disease (CD) due to the arrhythmogenic potential of this heart condition. This study aimed to evaluate the incidence and variables associated with arrhythmias during DSE in a population of patients with CD.

METHODS

A population of 205 consecutive patients with CD and suspected coronary heart disease was assessed through a retrospective database analysis. CD was confirmed in all patients by serological testing.

RESULTS

The mean age of the patients selected was 64 years, and 65.4% of the patients were female. Significant arrhythmias occurred as follows: nonsustained ventricular tachycardia in 7.3% of patients; supraventricular tachycardia and sustained ventricular tachycardia in 1%; and atrial fibrillation in 0.5%. Nonsignificant arrhythmias occurred as follows: premature ventricular contractions in 48% of patients and bigeminy in 4.4%. Values for the wall-motion score index at rest greater than 1.12 and 1.18 were independently correlated with the occurrence of nonsignificant arrhythmias (odds ratio [OR] = 2.90, P < 0.001) and significant arrhythmias (OR = 4.23, P = 0.044), respectively.

CONCLUSION

DSE should be considered a safe examination in patients with CD despite the known increased risk of arrhythmias in this group of patients. The occurrence of arrhythmias was low in this study. Abnormal wall-motion score index values at rest were associated with the occurrence of significant and nonsignificant arrhythmias during the test.

Occurrence of Atrial Fibrillation During Dobutamine Stress Echocardiography

Dobutamine stress echocardiography (DSE) is a widely used examination for assessment of coronary ischemia, but several complications have been reported. The aim of this study was to assess the incidence of atrial fibrillation (AF) during DSE, and a systematic review and meta-analysis were also performed to determine an accurate estimate of the AF incidence. Over a 16-year period, we reviewed all patients referred for DSE. We systematically analyzed all ECG performed during DSE to detect AF during the examination. DSE was completely performed in 4,818 patients (mean age: 62.1 ± 11.7 years). AF was observed in 40 patients (31 men, mean age: 79.7 ± 8.9 years). Incidence of AF during DSE was 0.83%. Regarding the meta-analysis, the combined AF incidence was 0.86%. In our study, patients with AF occurrence had more frequent previous history of paroxysmal AF (p = 0.02) were also older (p < 0.0001) and incidence of AF during DSE increased with age: 0% below 60 years, 0.45% in patients 60 to 69 years, 1.3% in patients 70 to 79 years, and 4% in patients >80 years (p < 0.0001). In multivariate analysis, the factors significantly associated with an increased risk of AF were age (adjusted odds ratio (aOR) = 2.4, 95% confidence interval: 1.5 to 3.3, p = 0.003) and previous history of paroxysmal AF (aOR = 1.5, 95% confidence interval: 1.1 to 1.9; p = 0.04). In conclusion, AF is uncommon during DSE, and elderly patients and patients with previous history of paroxysmal AF are at risk of AF during DSE.

L, Rassi S. Dobutamine Stress Echocardiography Safety in Chagas Disease Patients

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.

FUNDAMENTO:

Até poucas décadas atrás, os pacientes chagásicos eram predominantemente trabalhadores rurais, com baixo perfil de risco para doença obstrutiva coronária. Com a crescente urbanização, passaram a ter os mesmos fatores de risco para doença aterosclerótica que indivíduos não infectados. O ecocardiograma sob estresse com dobutamina (EED) é uma importante ferramenta no diagnóstico de coronariopatia. É referido, porém, como um método potencialmente arritmogênico, mas seguro, em pacientes coronarianos não chagásicos. Entretanto, há insegurança na prática clínica de indicá-lo no paciente chagásico, devido ao potencial arritmogênico já intrínseco nesta cardiopatia.

OBJETIVOS:

Analisar a segurança do EED em uma população de chagásicos com suspeita clínica de coronariopatia.

MÉTODOS:

Análise retrospectiva de um banco de dados de pacientes encaminhados para a realização do EED entre maio/2012 e fevereiro/2015. Avaliou-se pacientes consecutivos portadores de doença de Chagas e com suspeita de coronariopatia. Confirmou-se a sorologia para doença de Chagas em todos os pacientes.

RESULTADOS:

A média etária dos 205 pacientes analisados foi de 64 ± 10 anos, sendo a maioria do sexo feminino (65,4%). Nenhum paciente apresentou eventos adversos significativos, como infarto agudo do miocárdio, fibrilação ventricular, assistolia, acidente vascular encefálico, ruptura cardíaca ou morte. Quanto às arritmias, extrassístoles ventriculares frequentes ocorreram em 48% dos pacientes, taquicardia ventricular não sustentada em 7,3%, bigeminismo em 4,4%, taquicardia supraventricular e taquicardia ventricular sustentada em 1% e fibrilação atrial em 0,5%.

CONCLUSÃO:

O EED mostrou ser um exame seguro nessa população de pacientes chagásicos, onde nenhum desfecho grave foi encontrado.

A modified regimen of extracorporeal cardiac shock wave therapy for treatment of coronary artery disease

Background

Cardiac shock wave therapy (CSWT) improves cardiac function in patients with severe coronary artery disease (CAD). We aimed to evaluate the clinical outcomes of a new CSWT treatment regimen.

Methods

The 55 patients with severe CAD were randomly divided into 3 treatment groups. The control group (n = 14) received only medical therapy. In group A ( n = 20), CSWT was performed 3 times within 3 months. In group B ( n = 21), patients underwent 3 CSWT sessions/week, and 9 treatment sessions were completed within 1 month. Primary outcome measurement was 6-minute walk test (6MWT). Other measurements were also evaluated.

Results

The 6MWT, CCS grading of angina, dosage of nitroglycerin, NYHA classification, and SAQ scores were improved in group A and B compared to control group.

Conclusions

A CSWT protocol with 1 month treatment duration showed similar therapeutic efficacy compared to a protocol of 3 months duration.

Clinical trial registry

We have registered on ClinicalTrials.gov, the protocol ID is CSWT IN CHINA.

Electroacupuncture to ST36 ameliorates behavioral and biochemical responses to restraint stress in rats

OBJECTIVES

Acupuncture has been used for the treatment and prevention of stress-related disorders. In the present study, the effect of electroacupuncture on the behavioral and biochemical responses to restraint stress was evaluated in rats.

METHODS

Sprague-Dawley male rats underwent immobilization stress for 21 days (6 hours/day). Electroacupuncture (2 Hz, 2 mA and 10 minutes) was applied either to the acupuncture point ST36 (Joksamni) or the non-acupuncture point in the tail for the last 7 days. Rats were randomly divided into four groups: the normal group (n=10, without the restraint stress), the stress group (n=10, with restraint stress), the ST36 group (n=10, with restraint stress and electroacupuncture to ST36) and the non-acupuncture group (n=10, with restraint stress and electroacupuncture to the non-acupuncture point). The anxiety-related behavior was tested using the elevated plus maze and the Vogel test on day 22. The serum concentration of corticosterone was determined using an enzyme-linked immunosorbent assay kit. The expression of tyrosine hydroxylase in the locus coeruleus was measured by immunohistochemistry.

RESULTS

Restraint stress increased the response of the anxiety-related behavior. The serum level of corticosterone and the number of tyrosine hydroxylase-immunoreactive cells were also increased. The ST36 group showed a significant decrease of anxiety-related behavioral response, compared with the stress group. The serum corticosterone level and tyrosine hydroxylase-immunoreactive expression were also decreased in the ST36 group.

DISCUSSION

These findings suggest that electroacupuncture to ST36 might play a role in reducing the stress-related responses, which may be helpful for the treatment of stress-related disorders.