Regadenoson stress CMR: safety, feasibility and hemodynamic response

Background and objectives

The use of regadenoson for stress cardiac magnetic resonance (CMR) has potential advantages over other vasodilators. We sought to evaluate the safety, feasibility and hemodynamic response (heart rate and blood pressure) of regadenoson in an unselected population undergoing stress CMR for clinical work-up.

Methods

A total of 603 regadenoson stress CMR clinical examinations performed between May 2017 and May 2020 in our institution were retrospectively reviewed. Studies were performed using a conventional stress/rest CMR protocol with a 1.5T MRI scanner. A fixed dose of 5 ml of regadenoson was employed as stressor. As part of the protocol, 200 mg of theophylline was administered between stress and rest acquisitions to reverse the vasodilator effect of regadenoson. Adverse events, clinical symptoms, and hemodynamic response were assessed.

Results

In our cohort, no severe adverse events requiring hospitalization were observed, and only 5 adverse events were reported (0.83%). Only two patients (0.3%) did not complete the test due to adverse events or symptoms related to regadenoson administration (one case presented severe hypotension; the other presented unbearable chest pain). There were no cases of bronchospasm, stress-induced arrhythmia or death. Over half of patients reported mild symptoms after drug administration (52%, n=314), more frequently dyspnea (19%, n=112), chest pain (18%, n=106) and flushing (6%, n=34). All symptoms resolved after theophylline administration. Overall, an increase in heart rate (mean increase and (standard deviation) = 24 (12.6) bpm and a mild decrease in systolic (−8.2 (17.1) mmHg) and diastolic (−4.9 (10.2) mmHg) blood pressure were observed as response to regadenoson. A blunted heart rate response was observed in elderly (p<0.01), diabetic (p<0.01) and obese (p=0.01) patients. Only 46 patients (7.8%) did not show tachycardization response.

Conclusions

The use of regadenoson in stress CMR proved to be safe and feasible in the vast majority of patients. Adverse events were not frequent with regadenoson and symptoms were transient and well tolerated, while premature ending of the test related to drug administration was very rare.

Funding Acknowledgement

Type of funding sources: None. Hemodynamic response

P185 Primary cardiac lymphoma: an unexpected finding

BACKGROUND

Primary cardiac malignancies are rare, with a reported incidence of 0.1%. Up to 10% of cardiac tumors are malignant and primary cardiac lymphoma represents (PCL) a very low proportion of them. The wide variety of clinical manifestations and the inespecificity of them, difficults the diagnosis and delays treatment impacting directly in the prognosis of these patients. Here we present a lady with diagnosis of PCL treated in our center.

CASE REPORT

We present a 69 year old female with arterial hypertension and paroxismal atrial fibrilation that attended our clinic in april 2013. She referred severe dyspnoea with daily activities and peripheral oedema for the last three weeks. She also complaint of painful swallowing for bothliquids and solids. Physical exploration was unremarkable and observations where within normal limits. Transthoracic echocardiogram (TTE) was performed which showed an hipoechogenic mass invading the right ventricle, both atria and left ventricle outflow tract. She underwent cardiac MRI which revealed a myocardial isointense mass, with marked signal enhancement in T2 and heterogeneity in late gadolinium enhancement sequences, that was consistent with primary cardiac lymphoma. For histologycal characterization, biopsy of the mass guided with endoscopic ultrasonography was performed, confirming B-cell lymphoma. Positron emmision tomography (PET) scan showed bulky hypercaptant mass invading both atria, superior vena cava and pericardium, with hypercaptant adenopathies in right pulmonary hilum, subcarinal and phrenic chain. Her case was discussed in multidisciplinary team meeting and prompt initiation of treatment under R-CHOP regime was decided. After three cycles, follow up PET was requested, and revealed complete metabolic response. A repeat TTE showed only minimal infiltration of the right atria without ventricular involvement or hemodynamic compromise.

DISCUSSION

The patient we presented, was sent to Cardiology due to heart failure symptoms. Acute heart failure as well as embolisation and life-threatening arrythmias are typical manifestations of PCL. As reported in the literature, our case was a diffuse large B-cell lymphoma, which is the most frequent subtype. Dysphagia, exertional dyspnoea and constitutional symptoms can be present in early stages, as our patient referred. The main strength of this case is based on the quick diagnosis and early treatment. In contrary to what is reported, the overall survival was excellent, and to date the patient is still alive with no signs of relapse. Although TTE sensitivity is 55-60%, it has a key role in the diagnosis, which was supported later on MRI. Right chambers (specially right atria) are more typically involved than the left heart, including right venous drainage. Early systemic chemotherapy can achieve a high response rate and improve survival.

Abstract P185 Figure. Img1

P677 When to look for wtTTR amyloidosis in heart failure: increasing chances of positive gammagraphic study

Introduction

Wild type transtirretin (wtATTR) amyloidosis has become increasingly recognized as a major cause for heart failure (HF). Diagnosis requires complex work up such as DPD scintigraphy (DPDs). Availability of DPDs is limited urging to identify factors to increase its diagnostic rentability.

Methods

Retrospective study of HF patients between 2013 and 2019 with suspected wtATTR and DPDs was performed. Baseline characteristics, biomarkers, EKG findings, TTE parameters (LVEF, LV diastolic function, TAPSE, interventricular septum (IVS), LV mass (LVM), relative LV wall thickness (RWT), indexed LVTD volume and diameter, indexed LA diameter (iAPLAD)) and DPDs results were studied. Two groups were created according to DPDs (SP those with positive results for amyloidosis and SN those with negative results). For statistical SPSS v.21 was used.

Results

37 patients were studied. In our population 54% had positive DPDs for amyloidosis. Among SP patients 50% were classified as grade 2 of Perugini classification meanwhile 50% were grade 3; mean value of heart to contralateral ratio was 2,73 ± 0,8. There were no differences in NYHA classification. Differences among SP and SN patients are reflected in Table 1.

Conclusions

In our population SP was found to have higher biomarkers values and higher IVS, LVM, RWT and iAPLAD with poorer RV function. Further investigation is needed in order to confirm our result and identify prognostic factors.

Table 1: Results Total (37) PS (20) PN (17) p value Age (Y) 78 ± 7,9 80 ± 6,5 75,29 ± 8,7 0,05 Gender (male) (%) 30 (8) 19 (95) 11(64) 0,11 Carpal tunnel sdr (%) 3(8) 3 (15) 0 (0) 0,09 Systolic blood pressure (x ± sd) 127 ± 21 118 ± 18 138,5 ± 19 <0,01 ProBNP (x ± sd) 3596 ± 4002 4615 ± 4538 1761 ± 1927 <0,05 Troponin T (x ± sd) 132 ± 360 66,4 ± 35 43 ± 39 0,09 Pseudoinfarction pattern (%) 26 (70) 17 (85) 9 (52) <0,05 IVS (mm) (x ± sd) 14,6 ± 4,5 16,6 ± 5,3 13 ± 3 <0,01 LVM (g/m2) (x ± sd) 142,5 ± 68 180 ± 80 111 ± 32 <0,01 RWT (x ± sd) 0,68 ± 0,42 0,8 ± 0,24 0,56 ± 0,5 <0,01 LVEF (%) (x ± sd) 57,4 ± 11 54 ± 12 60 ± 10 0,12 iAPLAD (mm/m2) (x ± sd) 25,4 ± 6 28,7 ± 6 22,7 ± 4,3 <0,01 TAPSE (mm) (x ± sd) 18,6 ± 5 16,1 ± 4 20,6 ± 5 <0,05 IVS = interventricular septum; LVM = left ventricular mass; RWT = relative wall thickness; iAPLAD= indexed anteroposterior left atrium diameter.

Safety of regadenoson for vasodilation in cardiac MRI stress tests

OBJECTIVE

To determine the safety of regadenoson for vasodilation in cardiac MRI stress tests to detect myocardial ischemia.

MATERIAL AND METHODS

We retrospectively analyzed cardiac MRI studies done in 120 patients (mean age, 67±11.6 years; 88 men) with suspected ischemic heart disease or known coronary disease who had clinical indications for cardiac MRI stress tests. All studies were done on a 1.5 T scanner (MAGNETOM Aera, Siemens Healthineers) using regadenoson (5ml, 0.4mg) for vasodilation. We recorded cardiovascular risk factors, medications, and indications for the test as well as vital signs at rest and under stress and the symptoms and adverse effects induced by the drug.

RESULTS

No symptoms developed in 52.6% of patients. The most common symptoms were central chest pain (25%) and dyspnea (12%). At peak stress, the mean increase in heart rate was 23.9±11.4 beats per minute and the mean decreases in systolic and diastolic blood pressure were 7.1±18.8mmHg and 5.3±9.2mmHg, respectively (p <0.001). The response to regadenoson was less pronounced in obese and diabetic patients. The increase in heart rate was greater in symptomatic patients (27.4±11.2 bpm vs. 20.6±10.7 bpm in asymptomatic patients, p=0.001). No severe adverse effects were observed.

CONCLUSION

Regadenoson is well tolerated and can be safely used for cardiac MRI stress tests.

18F-FDG metabolism in a rat model of chronic infarction

Strategies to establish the functional benefit of cell therapy in cardiac regeneration and the potential mechanism are needed. Aims: Development of a semi-quantitative method for non invasive assessment of cardiac viability and function in a rat model of myocardial infarction (MI) based on the use of microPET. Animals, methods: Ten rats were subjected to myocardial imaging 2, 7, 14, 30, 60 and 90 days after left coronary artery ligation. Intravenous 18F-fluoro- 2-deoxy-2-D-glucose (18F-FDG) was administered and regional 18F activity concentrations per unit area were measured in 17 regions of interest (ROIs) drawn on cardiac polar maps. By comparing the differences in 18F uptake between baseline and each of the follow up time points, parametric polar maps of statistical significance (PPMSS) were calculated. Left ventricular ejection fraction (LVEF) was blindly assessed echocardiographically. All animals were sacrificed for histopathological analysis after 90 days. Results: The diagnostic quality of 18F-FDG microPET images was excellent. PPMSS demonstrated a statistically significant decrease in 18F concentrations as early as 48 hours after MI in 4 of the 17 ROIs (segments 7, 13, 16 and 17; p <0.05) that persisted throughout the study. Semiquantitative analysis of 18F-FDG uptake correlated with echocardiographic decrease in LVEF (p <0.001). Conclusion: The use of PPMSS based on 18F-FDG-microPET provides valuable semi-quantitative information of heart glucose metabolism allowing for non-invasive follow up thus representing a useful strategy for assessment of novel therapies in cardiac regeneration.

Hyponatraemia and congestive heart failure refractory to diuretic treatment. Utility of tolvaptan

Heart failure (HF) is currently one of the most significant healthcare problems in Spain and has a continuously increasing prevalence. Advances in our understanding of the various biological responses that promote cardiac remodelling and pulmonary venous congestion constitute the basis of current treatment. This article, prepared by members of the HF groups of the Spanish Society of Cardiology and the Spanish Society of Internal Medicine, discusses the current therapeutic strategies for patients with congestion refractory to diuretic treatment. The article includes our clinical experience with the use of tolvaptan as an additional treatment for congestion associated with hyponatraemia. To this end, we propose an algorithm for the use of tolvaptan in patients with congestive HF, natraemia <130mEq/l and poor response to conventional diuretic treatment.

Increased liver stiffness values in patients with heart failure

BACKGROUND

Liver stiffness has been claimed to be increased in patients with heart failure.

AIMS

To determine the magnitude of this increase in liver stiffness, and to clarify whether it is related to the degree of heart failure or not.

METHODS

Twenty-six patients were prospectively collected, and divided in groups CHF (those with compensated chronic heart failure) and AHF (those with acute decompensated heart failure). Patients underwent routine blood chemistries, pro-BNP determination, echocardiography and transient elastography during outpatient care (group CHF) or at hospital admission (group AHF). Blood chemistries, pro-BNP and transient elastography were repeated in patients in group AHF before being discharged.

RESULTS

Correlation between liver stiffness and pro-BNP levels was statistically significant (Rho = 0.747, p = 0.001). Patients in group CHF had lower values of liver stiffness and pro-BNP when compared with patients in group AHF at admission. Median liver stiffness and pro-BNP values were 6.5 vs 14.4 kPa (p = 0.009) and 1511 vs 3535 pg/ml (p = 0.025) respectively. After clinical compensation, liver stiffness decreased in all patients in group AHF. Liver stiffness was 14.4 kPa at admission and 8.2 kPa at discharge (p = 0.008). Pro-BNP values also decreased from a median of 3535 pg/ml to a median of 1098 pg/ml (p = 0.025).

CONCLUSIONS

Patients with heart failure have increased liver stiffness, that appears to be related with the severity of heart failure.

18F-FDG metabolism in a rat model of chronic infarction: a 17-sector semiquantitative analysis

Strategies to establish the functional benefit of cell therapy in cardiac regeneration and the potential mechanism are needed.

AIMS

Development of a semi-quantitative method for non invasive assessment of cardiac viability and function in a rat model of myocardial infarction (MI) based on the use of microPET.

ANIMALS, METHODS

Ten rats were subjected to myocardial imaging 2, 7, 14, 30, 60 and 90 days after left coronary artery ligation. Intravenous 18F-fluoro-2-deoxy-2-D-glucose (18F-FDG) was administered and regional 18F activity concentrations per unit area were measured in 17 regions of interest (ROIs) drawn on cardiac polar maps. By comparing the differences in 18F uptake between baseline and each of the follow up time points, parametric polar maps of statistical significance (PPMSS) were calculated. Left ventricular ejection fraction (LVEF) was blindly assessed echocardiographically. All animals were sacrificed for histopathological analysis after 90 days.

RESULTS

The diagnostic quality of 18F-FDG microPET images was excellent. PPMSS demonstrated a statistically significant decrease in 18F concentrations as early as 48 hours after MI in 4 of the 17 ROIs (segments 7, 13, 16 and 17; p < 0.05) that persisted throughout the study. Semiquantitative analysis of 18F-FDG uptake correlated with echocardiographic decrease in LVEF (p < 0.001).

CONCLUSION

The use of PPMSS based on 18F-FDG-microPET provides valuable semi-quantitative information of heart glucose metabolism allowing for non-invasive follow up thus representing a useful strategy for assessment of novel therapies in cardiac regeneration.

[Cell transplant and regenerative therapy with stem cells]

One of the fields of medicine that has raised the most expectations in recent years is cell therapy with stem cells. The isolation of human embryo cells, the apparent and unexpected potentiality of adult stem cells and the development of gene therapy lead us to imagine a hopeful future for a significant number of diseases that are at present incurable. In this article we will sketch out the panorama of stem cell research, describing the main achievements in this field as well as some of the questions that await an answer. In spite of the great expectations, it is essential that we maintain a critical and realistic spirit when it comes to analysing the scientific advances in this area.

[Heart transplant]

A heart transplant is at present considered the treatment of choice in cases of terminal cardiac insufficiency refractory to medical or surgical treatment. Due to factors such as the greater life expectancy of the population and the more efficient management of acute coronary syndromes, there is an increasing number of people who suffer from heart failure. It is estimated that the prevalence of the disease in developed countries is around 1%; of this figure, some 10% are in an advanced stage and are thus potential receptors of a heart transplant. The problem is that it is still not possible to offer this therapeutic form to all of the patients that require it. Consequently, it is necessary to optimise the results of the heart transplant through the selection of patients, selection and management of donors, perioperative management and control of the disease due to graft rejection. Since the first transplant carried out in 1967, numerous advances and changes have taken place, which has made it possible to increase survival and quality of life of those who have received a new heart. In this article we review the most relevant aspects of the heart transplant and the challenges that are currently faced.

Preliminary Results of the Effect of Treatment of Hyperhomocysteinemia and Its Relationship With Inflammation, Coagulation Status, and Endothelial Function After Renal Transplantation

The aim of this study was to assess the relationship between total plasma homocysteine (tHC) and several markers of endothelial function, coagulation, and pro-inflammatory status in renal transplant recipients. Our own previous study demonstrated the efficacy of folic acid (FA) and vitamin B(12) (B(12)) treatment to reduce tHC. Using 70 stable recipients, 56 of whom showed hyperhomocisteinemia (HHC) (tHC > or = 14 micromol/L) and a control group (n = 14, tHC < 14 micromol/L), we treated 29 patients in the HHC group (10 mg FA and 500 mg B(12) daily) and determined their endothelial function, inflammatory activity, and coagulation status. We assessed plasma levels of von Willebrand Factor and fibrinogen as the prothrombotic profile and C-reactive protein and plasma albumin as inflammation markers. We performed Doppler sonography of the brachial artery to assess endothelial function. The mean value of plasma tHC of 19.05 +/- 3.70 micromol/L before treatment decreased to 13.45 +/- 3.25 micromol/L after 3 months of treatment (P < .001). The vWF was significantly correlated with tHC (P < .05) and was higher in the HHC patients (P < .05). The fibrinogen mean level was also significantly higher in HHC patients (P < .05). The C-reactive protein level was significantly higher and the albumin level was lower among patients with HHC. The endothelium-dependent dilation (EDD) correlated with baseline tHC (P < .05). In preliminary data we observed that homocysteine-lowering therapy may provide cardiovascular protection by enhancing endothelial function, limiting oxidative stress, and reducing procoagulation status.

[Supraventricular arrhythmia. Potential applications of esmolol]

Atrial fibrillation, atrial flutter, paroxistical supraventricular tachycardias and atrial tachycardias are the main supraventricular arrhythmias. Atrial fibrillation is the most common. In this review we comment their physiopathology, clinical manifestations, and treatments, paying special attention to the possible esmolol applications.