Aspirin plus verapamil relieves angina and perfusion abnormalities in patients with coronary microvascular dysfunction and Chagas disease: a pilot non-randomized study

Abstract INTRODUCTION: Most patients with chronic cardiomyopathy of Chagas disease (CCCD) harbor a secondary cause of coronary microvascular dysfunction (CMD), for which there is no evidence-based therapy. We evaluated the impact of verapamil plus aspirin on symptoms and perfusion abnormalities in patients with CCCD and CMD. METHODS: Consecutive patients with angina pectoris, who had neither coronary artery obstructions nor moderate-severe left ventricular dysfunction (left ventricular ejection fraction > 40%) despite showing wall motion abnormalities on ventriculography, were referred for invasive angiography and tested for Chagas disease. Thirty-two patients with confirmed CCCD and ischemia on stress-rest SPECT myocardial perfusion scintigraphy (MPS) were included. Clinical evaluation, quality of life (EQ-5D/ Seattle Angina Questionnaire), and MPS were assessed before and after 3 months of treatment with oral verapamil plus aspirin (n=26) or placebo (n=6). RESULTS: The mean patient age was 64 years, and 18 (56%) were female. The ischemic index summed difference score (SDS) in MPS was significantly reduced by 55.6% after aspirin+verapamil treatment. A decrease in SDS was observed in 20 (77%) participants, and in 10 participants, no more ischemia could be detected. Enhancements in quality of life were also detected. No change in symptoms or MPS was observed in the placebo group. CONCLUSIONS: This low-cost 3-month treatment for patients diagnosed with CCCD and CMD was safe and resulted in a 55.6% reduction in ischemic burden, symptomatic improvement, and better quality of life.

Utilização de radiofármacos marcados com tecnécio 99m como potenciais marcadores na obtenção de imagens de perfusão miocárdica / Using technetium-99m-marked radiopharmaceuticals as potential markers in obtaining myocardial perfusion images

A Organização Mundial de Saúde (OMS) aponta as doenças cardiovasculares como a principal causa de morte no mundo, caracterizando um grave problema na saúde pública. Os três tipos de doenças que mais acarretam em óbito são: acidente vascular cerebral, seguido de infarto agudo do miocárdio e outras doenças isquêmicas do coração.Apesar dos avanços terapêuticos das últimas décadas, o infarto ainda apresenta altas taxas de mortalidade. Para as pessoas com doenças cardiovasculares ou com alto risco cardiovascular é fundamental o diagnóstico precoce da doença. A cintilografia de perfusão miocárdica é um método de investigação diagnóstica e prognóstico não invasivo de várias doenças cardiovasculares. Esse exame consiste na administração de um radiofármaco para obtenção de imagens de perfusão cardíaca. Dois traçadores marcados com Tecnécio-99m são amplamente utilizados na clínica, porém, esses dois radiofármacos não atendem aos requisitos de um agente de perfusão ideal, por sofrerem significativa excreção biliar, produzindo artefatos na imagem, o que pode inteferir um diagnóstico preciso, já que a qualidade é comprometida, e prolongando o tempo de obtenção da imagem após a administração do radiotraçador. Para superar essa lacuna, pesquisadores vêm estudando novos complexos catiônicos marcados com o Tecnécio. O objetivo desse artigo é fazer uma revisão, abordando a literatura sobre os radiofármacos que estão sendo estudados, suas vantagens e desvantagens sobre os traçadores já utilizados, e sobre sua potencial utilização na obtenção de imagem de perfusão cardíaca.

The World Health Organization (WHO) acknowledges cardiovascular diseases as the leading cause of death in the world, being regarded as a serious public health issue. The three types of diseases with the greatest mortality are: stroke, followed by acute myocardial infarction (AMI) and other ischemic heart diseases. Despite the therapeutic advances of the last decades, AMI still presents high mortality rates. Early diagnosis is essential for people with cardiovascular diseases or with a high cardiovascular risk. Myocardial perfusion scintigraphy is a method of diagnostic investigation and noninvasive prognosis of various cardiovascular diseases. This examination consists in the administration of a radiopharmaceutical drug to obtain images of cardiac perfusion. Two tracers labeled with Technetium-99m are widely used, however, these two radiopharmaceuticals do not meet the requirements of an ideal perfusion agent, because they have a high liver absorption, producing artifacts in the image, which can disrupt a precise diagnosis, since the quality is compromised, and prolonging the imaging time after administration of the radioisotope. To overcome this gap, researchers have been studying new cationic complexes marked with technetium. The objective of this article is to review the literature on the radiopharmaceuticals being studied, their advantages and disadvantages on the tracers already used, and their potential use in obtaining a cardiac perfusion image.

Improvement of the Ischemic Area after Surgical Treatment for Anomalous Origin of the Right Coronary Artery from the Pulmonary Artery / 日本心臓血管外科学会雑誌

Anomalous origin of the right coronary artery from the pulmonary artery (ARCAPA) is a rare congenital coronary anomaly. Although asymptomatic in most cases, with the anomaly only being detected incidentally, surgical correction should be considered before onset of severe myocardial ischemia in such cases. Here, we present a 70-year-old man who was referred to our department due to chest pain on effort and was given a diagnosis of ARCAPA concomitant with mild aortic stenosis. As the symptoms and the degree of aortic stenosis deteriorated during follow-up, the patient underwent direct re-implantation of the right coronary artery into the ascending aorta and aortic valve replacement. The patient's postoperative course was uneventful, and the symptoms disappeared. Postoperative myocardial perfusion scintigraphy revealed improvement of the myocardial ischemic area.

Correlation of left ventricular eccentricity index with other scintigraphic parameters on gated myocardial perfusion single photon emission computed tomography

Background@#Left ventricular (LV) eccentricity index (EI) is a measure of the LV shapre obtained with a commonly used quantitative software for mycardial perfusion scintigraphy (MPS). However, there are limited studies evaluating its correlation with other MPS parameters, for which this study was done. @*Methodology@#All patients who underwent 99mTc-sestamibi stress MPS from 2013 to 2015 were screened. A total of 353 patients, 228 (65%) males and 125 (35%) females, met the inclusion criteria. One hundred twenty-nine (37%) underwent exercise stress while 224 (63%) were given dipyridamole. Spearman's rho correlation was used to determine the correlation of rest and post-stress EI with the other study variables. @*Results@#Among males, rest EI showed negative correlation with summed stress score (SSS) (rs = -0.182, p<0.005), transient ischemic dilatation (TID) (rs=-0.172, p=0.009), rest LV end-diastolic volume (EDV) (rs=-0.291, p < 0.001), rest LV end-systolic volume (ESV)(rs=-0.316, p < 0.001), p0-st-streSS LVEDV (rs= -0.218, p < 0.001), and post-stress LVESV (rs= -0.331, p < 0.001). There was positive correlation with rest LV ejection fraction (EF) (rs= 0.291,p < 0.001) and post-stress LVEF (r5 = 0. 336, p < 0. 001). No sig11ifico11t relationship with any of the MPS parameters was observed among females. For both exercise and dipyridamole groups. EI exhibited negative correlation with SSS, and rest and stress LVESV; and positive cotrelation with rest and post-stress LVEF. Significant relationship with rest and stress LVEDV was only observed in the dipyridamole group.@*Conclusions@#This study shows that EI is correlated with most, if not all, of the MPS parameters with different levels of association depending on the patient's sex and the type of stress employed. More spherical LV is correlated with more severe perfusion defects, larger LV cavity volumes and poorere LV systolic function.

Anomalous origin of the left coronary artery arising from the pulmonary artery: Myocardial perfusion scintigraphy findings

Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital cardiac disease with serious complications. This is a case of a three-year-old female who was initially diagnosed and managed as a case of dilated cardiomyopathy. A 2-D echocardiogram showed the left main coronary artery to be coming from the pulmonary artery. The patient was referred for myocardial perfusion scintigraphy (MPS) to determine viability prior to surgical revascularization. MPS showed absent myocardial perfusion in the apex and apical anterior segments and thinned-out perfused myocardium in the midventricular to basal anterior segment and apical to basal inferior and lateral walls. This is consistent with markedly reduced perfusion in the segments supplied by the anomalous left coronary artery distribution. While echo cardiography and angiography are used to diagnose ALCAPA, the roles of MPS are to provide information regarding the viability of the areas supplied by the anomalous left coronary artery and to assess postoperative myocardial perfusion.

Myocardial perfusion scintigraphy in tetralogy of fallot prior to total correction of a non-patent shunt

This paper presents a clinical situation in which a Technetium 99m sestamibi myocardial perfusion scintigraphy (MPS) with dipyridamole was used as part of the preoperative evaluation in a 15 year old female with Tetralogy of Fallot. MPS revealed no evident inducible myocardial ischemia, depressed LV wall function and RVH but with good RV function. There are many different techniques for imaging and studying patients with Tetralogy of Fallot (TOF). Echocardiography, ventriculography and invasive angiography remain the mainstay in its evaluation. However, the presence of coronary anomalies in these patients is very common and has negative effect on myocardial perfusion, either preoperatively or postoperatively. Hence, MPS plays an essential role in providing complete assessment in this group of patients.

Stress Testing and Imaging Protocols for Myocardial Perfusion Studies / 핵의학분자영상

Scince 201Tl was introduced as a myocardial perfusion imaging agent in the early 1970s, scintigraphic evaluation of myocardial perfusion for the diagnosis of coronary artery disease is a valuable noninvasive diagnostic imaging modality. Stress radionuclide myocardial perfusion imaging is widely accepted to have high diagnostic and prognostic use in the assessment of patients with known or suspected coronary artery disease. With wise use of this nonivasive imaging technique, more patients are referred for stress perfusion imaging. Until now various protocols for stress testing and myocardial imaging were developed and used in worldwide. This article presented various protocols of stress testing and myocardial imaging for clinical use.

Assessment of Prognosis and Risk Stratification in Coronary Artery Disease / 핵의학분자영상

Risk stratification and assessment of prognosis in patients with known or suspected CAD is of crucial important for the practice of contemporary medicine. Noninvasive testing such as myocardial perfusion scintigraphy, coronary artery calcium scoring or CT coronary angiography is increasingly being used to determine the need for aggressive medical therapy and to select patients for catheterization. The integrated anatomic and functional information may provide more additional information for the cardiologist or other clinician by the improved risk stratification and diagnostic accuracy of integrated techniques. The development of SPECT/CT or PET/CT hybrid systems is therefore of important value for the nuclear cardiology.

Protocols of Myocardial Perfusion SPECT / 대한핵의학회잡지

In myocardial perfusion scintigraphy, the results of this evalution now confront the practitioner of nuclear medicine with methodologic options. Most nuclear cardiologic studies are performed using thallium-201, Tc-99m sestamibi and Tc-99m tetrofosmin. Some part of these studies use some form of pharmacologic stress test. While tailoring each test to the individual is ideal, this may be impractical for a busy department. Accordingly, established protocols to be used for patients with similar clinical presentations will be helpful. The following review presents methodology of various imaging protocols mainly according to the guidelines of nuclear cardiology procedures in American Society of Nuclear Cardiology.

Prognostic Value of Normal Exercise (99m)Te-MIBI Myocardial Perfusion SPECT: Comparison with Exercise Electrocardiography and Coronary Angiography / 대한핵의학회잡지

PURPOSE: Myocardial perfusion scintigraphy is a useful technique to diagnose and to predict prognosis in patients with suspected or known coronary artery disease. The purpose of the present study is to evaluate the prognostic value of normal exercise (99m)Tc-MIRI myocardial perfusion single photon emission computed tomography (SPECT) an(l to analyze results with regard to those of exercise. electrocardiography or coronary angiography. MATERIALS AND METHODS: We evaluated 30) patients (mean age S2+/-10 years, 166 males and 135 females) with normal exercise (99m)Tc-MIBI myocardial perfusion SPECT performed for suspected coronary artery disease. Subjects were evaluated for cardiac events and followed for 8-55 months (mean 19+/-10 months) after imaging. RESULTS: During the follow-up period, there was no cardiac death but only one non-fatal myocardial infarction (event rate 0,21%: per year). In addition, only one patient underwent coronary revascularization. There was no significant difference in cardiac event rate between patients with positive (n=27) and negative (n-235) exercise electrocardiography (p:NS), There was no cardiac event in ]7 patients who underwent coronary angiography (4 patients with >50% luminal narrowing, 2 patients with vasospasm and 11 patients with no significant lesion). CONCLUSION: Patients with normal exercise (99m)Tc-MIBI myocardial perfusion SPECT has a very low risk for cardiac events regardless of exercise electrocardiographic and coronary angiographic findings.

Estudo de perfusão miocárdica em portadores de bloqueio de ramo direito / Myocardial perfusion study in patients with right bundle branch block

PURPOSE: To evaluate the sensitivity and specificity of myocardial perfusion scintigraphy in the detection of coronary artery disease in patients with right bundle branch block (RBBB). METHODS: Thirty one patients (24 male, 62.3 +/- 10.5 years) with RBBB, submitted to myocardial perfusion scintigraphy associated with exercise (n = 7) or dipyridamole (n = 24) and previous cinecoronariography were studied retrospectively. Left ventricle scintigraphic image was divided in three segments corresponding to the three main epicardic coronary territories in a total of 93 segments. Cineangiographic and scintigraphic data were then compared according to the different artery territories. RESULTS: Twenty three patients had significant lesions (> or = 60) in one or more coronary arteries and eight had no obstruction. Forty nine segments were irrigated by normal coronary arteries and 44 were related to arteries that had significant lesions. Twenty out of twenty three patients showed alterations in perfusion (sensitivity = 87). All patients without coronary obstructions showed normal perfusion scintigraphy (specificity = 100). One of the segments perfused by normal coronaries showed abnormal scintigraphy. Scintigraphy showed perfusion defects in 29 out of 44 segments with coronary obstructions. Sensitivity and specificity of the method for each arterial territory were 72and 100(left descending coronary artery), 67and 94(right coronary artery), 55and 100(circunflex coronary artery), respectively. CONCLUSION: The presence of RBBB does not modify the sensitivity and specificity of the method in the detection of coronary artery disease.

Comparison of Stress-rest and Rest-stress One Day Myocardial Perfusion Scintigraphies in Detecting Coronary Artery Diseases / 대한핵의학회잡지

It has been shown that both rest and stress myocardial perfusion imagings with technetium agents can be performed on the same day using two different doses injected within few hours. The purpose of this study was to compare the two protocols (stress-rest and rest-stress) in detecting coronary artery diseases. One hundred and sixty patients (101 males, 59 females, mean age 57+/-9 years) and 120 patients (79 males, 41 females, mean age 59+/-10 years) underwent stress-rest myocardial perfusion SPECT and rest-stress myocardial perfusion SPECT, respectively All of them underwent both myocardial perfusion SPECT and coronary angiography within 1 month. A coronary stenosis was considered significant when it compromised the luminal diameter by> or =50%. The chi square test was used to compare differences in sensitivity, specificity and accuracy between the two groups. The overall sensitivity, specificity and accuracy of stress-rest protocol were 99%, 35%and 68%, respectively. Those of rest-stress protocol were 96%, 47%, and 78%, respectively. There was no difference between the two protocols in identifying individual diseased coronary artery branches. Therefore, one day stress-rest and rest-stress myocardial SPECT using Tc-99m agents were comparable and were very sensitive tests in detecting coronary artery diseases.

Prognostic Implication of Normal Myocardial Perfusion Scintigraphy in Patients with Chest Pain / 대한핵의학회잡지

Myocardial scintigraphy is a widely used noninvasive procedure with high sensitivity for the detection of patients with suspected coronary artery disease. The purpose of this study was to determine the prognostic value of a normal myocardial scintigraphy in 292 patients (150 males, 142 females, mean age 53+/-12 years) with chest pain who were followed from 7 to 58 (mean 25) months. Myocardial SPECT was performed with Tc-99m MIBI in 173 patients, with Tc-99m tetrofosmin in 74 patients and with T1-201 in 45 patients. During the follow-up period, there were 2 cardiac deaths and 2 nonfatal myocardial infarctions resulting in cardiac event rate of 1.37% (0.66% per year). The cardiac event rate was not different in patients with angiographically normal coronary arteries (1/30, 3.3%) and in those who had significant coronary a disease (2/27, 7.4%) (p=0.60). In conclusion, patients with chest pain and normal myocardial scintigraphy have a low cardiac event rate, and there was no significant difference of cardiac event rates between patients with normal and abnormal coronary angiograms.