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

Cooperation between passive and active silicon transporters clarifies the ecophysiology and evolution of biosilicification in sponges

The biological utilization of dissolved silicon (DSi) influences ocean ecology and biogeochemistry. In the deep sea, hexactinellid sponges are major DSi consumers that remain poorly understood. Their DSi consumption departs from the Michaelis-Menten kinetics of shallow-water demosponges and appears particularly maladapted to incorporating DSi from the modest concentrations typical of the modern ocean. Why did sponges not adapt to the shrinking DSi availability that followed diatom expansion some 100 to 65 million years ago? We propose that sponges incorporate DSi combining passive (aquaglyceroporins) and active (ArsB) transporters, while only active transporters (SITs) operate in diatoms and choanoflagellates. Evolution of greater silicon transport efficiency appears constrained by the additional role of aquaglyceroporins in transporting essential metalloids other than silicon. We discuss the possibility that lower energy costs may have driven replacement of ancestral SITs by less efficient aquaglyceroporins, and discuss the functional implications of conservation of aquaglyceroporin-mediated DSi utilization in vertebrates.

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.

Occurrence of somatic cells within the spermatic cysts of demosponges: a discussion of their role

During ultrastructural studies on the spermatogenesis of two demosponges, Raspaciona aculeata and Petrosia ficiformis, somatic cells were detected within their spermatic cysts. In R. aculeata large, amoeboid somatic cells, presumably derived from follicle cells, were found inside cysts filled with secondary spermatocytes. These cells were actively phagocytosing spermatocytes. Such phagocytosis could be directed to eliminate aberrant spermatogenic cells, maintain appropriate cell number within the cysts, or recapture energetic reserves originally allocated to the reproductive process via phagocytosis of spermatocytes. In P. ficiformis, somatic round cells were observed only after the spawning event, phagocytosing unspawned sperm in nearly emptied spermatic cysts. Unlike in R. aculeata, these cells were more similar to archaeocytes (common cells of the demosponge mesohyl with phagocytic activity) than to follicle cells. Phagocytosis of spermatogenic cells and unspawned spermatozoa by somatic cells from the wall of the testes is a well-known process in vertebrates and many invertebrates. Occurrence of somatic cells in the spermatic cysts of sponges, whose function appears to be partially analogous to that of Sertoli cells, reveals that sponges possess cellular mechanisms to regulate testis functioning that are equivalent to those in higher metazoans.

[Renal function and cardiovascular risk in patients with essential hypertension. The "FRESHA" study]

BACKGROUND

In the past few years there has been a growing amount of information about renal dysfunction and cardiovascular risk. The objectives of this study were to assess the prevalence of renal dysfunction and evaluate the relation between renal function and cardiovascular risk in patients with essential hypertension.

METHODS

A multicenter, cross-sectional survey of unselected patients with essential hypertension attending primary care settings in Spain was performed between june and november 2004. Renal function was evaluated with the abbreviated equation of the Modification of Diet in Renal Disease study. Renal insufficiency was defined as an estimated glomerular filtration rate <60 ml/min/1.73 m2.

RESULTS

Eighty-eight investigators from 50 centers recruited 2130 patients being mean age 65.6 +/- 11 years and female 53%. Prevalence of diabetes, lipid abnormalities, and previous cardiovascular disease were 30.3%, 45.9%, and 42.1% respectively. Prevalence of renal insufficiency was 32.4% (95% CI 30.4-34.4). Patients suffering from renal insufficiency showed a higher prevalence of cardiovascular disease when comparing with those with an estimated glomerular filtration rate = or >60 ml/min/1.73 m2 (56.2% vs. 35.3%, OR 2.35, 95% CI 1.95-2.82, p < 0.001). A logistic regression analysis showed that the relation of renal dysfunction with cardiovascular disease was independent of other variables or classical cardiovascular risk factors as age, female sex, diabetes, smoking, hypercholesterolemia, and systolic blood pressure.

CONCLUSIONS

Renal insufficiency was present in 32.4% of patients with essential hypertension attending primary care settings. Cases with renal dysfunction showed a higher cardiovascular risk. Hypertensive patients with renal insufficiency should be considered as candidates for an aggressive approach of cardiovascular risk management.

[Acute left ventricular systolic dysfunction after pericardial effusion drainage]

A patient with a thymoma and initially normal ventricular systolic function developed cardiac tamponade, which was relieved by pericardiocentesis. After four days, the tumor was removed and, one week after the relief of tamponade, she developed severe left ventricular systolic dysfunction, that recovered in three days with venous therapy.