Zero-contrast imaging for the assessment of transcatheter aortic valve implantation in candidates with renal dysfunction

BACKGROUND

Candidates for transcatheter aortic valve implantation (TAVI) are currently evaluated using computed tomography angiography and invasive cardiac catheterization as an essential part of case selection and pre-procedure interventional planning. However, both imaging methods utilize iodinated agents, which may cause contrast-induced nephropathy, particularly in patients with baseline renal dysfunction. This study aimed to describe a zero-contrast imaging protocol for pre-TAVI evaluation in patients with advanced renal impairment.

METHODS

The pre-TAVI zero-contrast scheme consisted of the following multi-modality combinations: (1) gadolinium-free magnetic resonance imaging (three-dimensional navigator-echo with electrocardiogram-gated steady-state free-precession series); (2) iodinated-free multislice computed tomography electrocardiogram-gated; (3) lower limb arterial duplex scan ultrasound; and (4) transesophageal echocardiography. Ultimately, TAVI was performed for those deemed good candidates, and contrast was allowed during the intervention; however, operators were strongly advised to utilize the least volume possible of iodinated agents. This pilot survey included ten patients with symptomatic aortic stenosis and renal dysfunction who underwent zero-contrast multi-modality imaging.

RESULTS

All the patients ultimately underwent TAVI. The intervention was successful in all cases, without ≥ moderate residual aortic regurgitation, prosthesis embolization, annulus rupture, major vascular complications, stroke, or death during index hospitalization. The creatinine clearance remained stable throughout the observation period (baseline: 26.85 ± 12.55 mL/min; after multi-modality imaging: 26.76 ± 11.51 mL/min; post-TAVI at discharge: 29.84 ± 13.98 mL/min; p = 0.3 all).

CONCLUSION

The proposed contrast-free imaging protocol appears to be a promising clinical tool for pre-TAVI evaluation in patients with severe renal dysfunction.

Exercise Training on Anginal Threshold Does Not Improve Endothelial Function in Refractory Angina Patients

Refractory angina (RA) is a chronic condition of coronary artery disease (CAD). Endothelial function (EF) measured by flow-mediated dilation (FMD) is an important prognostic marker in CAD. Exercise training is a stimulus that improves EF in CAD. However, exercise training effects on EF in RA are unknown. Therefore, we aimed to verify the effects of exercise training on EF in RA. This was a longitudinal, non-randomized clinical study, involving patients with patients limited by angina, aged 45 to 75 years. Patients were prospectively allocated by convenience to either exercise trained (ET) or control group (C). Laboratory analysis, cardiopulmonary exercise test (CPET), and FMD were implemented at inclusion and after 12 weeks of exercise training or clinical treatment period. Exercise training included 60 minutes per session, 3 times a week, including 40 minutes of aerobic exercise on anginal threshold heart rate obtained on the CPET, 15 minutes of resistance training, and 5 minutes of stretching. A total of 38 patients were included (mean age 60 ± 9 years, 22 men); 21 were allocated to the ET and 17 to the C group. Baseline measures showed no differences between groups. After 12 weeks glycated hemoglobin and systolic blood pressure were lower in ET before than ET after (p = 0.004, and p = 0.05, respectively), and exercise time of the CPET was lower in ET before than ET after (p = 0.002). Exercise training did not change FMD. In conclusion, exercise training performed on anginal threshold increases exercise tolerance but causes no changes in EF in patients with RA.

Risk prediction in patients with classical low-flow, low-gradient aortic stenosis undergoing surgical intervention

Introduction

Classical low-flow, low-gradient aortic stenosis (LFLG-AS) is an advanced stage of aortic stenosis, which has a poor prognosis with medical treatment and a high operative mortality after surgical aortic valve replacement (SAVR). There is currently a paucity of information regarding the current prognosis of classical LFLG-AS patients undergoing SAVR and the lack of a reliable risk assessment tool for this particular subset of AS patients. The present study aims to assess mortality predictors in a population of classical LFLG-AS patients undergoing SAVR.

Methods

This is a prospective study including 41 consecutive classical LFLG-AS patients (aortic valve area ≤1.0 cm², mean transaortic gradient <40 mmHg, left ventricular ejection fraction <50%). All patients underwent dobutamine stress echocardiography (DSE), 3D echocardiography, and T1 mapping cardiac magnetic resonance (CMR). Patients with pseudo-severe aortic stenosis were excluded. Patients were divided into groups according to the median value of the mean transaortic gradient (≤25 and >25 mmHg). All-cause, intraprocedural, 30-day, and 1-year mortality rates were evaluated.

Results

All of the patients had degenerative aortic stenosis, with a median age of 66 (60-73) years; most of the patients were men (83%). The median EuroSCORE II was 2.19% (1.5%-4.78%), and the median STS was 2.19% (1.6%-3.99%). On DSE, 73.2% had flow reserve (FR), i.e., an increase in stroke volume ≥20% during DSE, with no significant differences between groups. On CMR, late gadolinium enhancement mass was lower in the group with mean transaortic gradient >25 mmHg [2.0 (0.0-8.9) g vs. 8.5 (2.3-15.0) g; p = 0.034), and myocardium extracellular volume (ECV) and indexed ECV were similar between groups. The 30-day and 1-year mortality rates were 14.6% and 43.8%, respectively. The median follow-up was 4.1 (0.3-5.1) years. By multivariate analysis adjusted for FR, only the mean transaortic gradient was an independent predictor of mortality (hazard ratio: 0.923, 95% confidence interval: 0.864-0.986, p = 0.019). A mean transaortic gradient ≤25 mmHg was associated with higher all-cause mortality rates (log-rank p = 0.038), while there was no difference in mortality regarding FR status (log-rank p = 0.114).

Conclusions

In patients with classical LFLG-AS undergoing SAVR, the mean transaortic gradient was the only independent mortality predictor in patients with LFLG-AS, especially if ≤25 mmHg. The absence of left ventricular FR had no prognostic impact on long-term outcomes.

Multimodality imaging methods and systemic biomarkers in classical low-flow low-gradient aortic stenosis: Key findings for risk stratification

Objectives

The aim of the present study is to assess multimodality imaging findings according to systemic biomarkers, high-sensitivity troponin I (hsTnI) and B-type natriuretic peptide (BNP) levels, in low-flow, low-gradient aortic stenosis (LFLG-AS).

Background

Elevated levels of BNP and hsTnI have been related with poor prognosis in patients with LFLG-AS.

Methods

Prospective study with LFLG-AS patients that underwent hsTnI, BNP, coronary angiography, cardiac magnetic resonance (CMR) with T1 mapping, echocardiogram and dobutamine stress echocardiogram. Patients were divided into 3 groups according to BNP and hsTnI levels: Group 1 (n = 17) when BNP and hsTnI levels were below median [BNP < 1.98 fold upper reference limit (URL) and hsTnI < 1.8 fold URL]; Group 2 (n = 14) when BNP or hsTnI were higher than median; and Group 3 (n = 18) when both hsTnI and BNP were higher than median.

Results

49 patients included in 3 groups. Clinical characteristics (including risk scores) were similar among groups. Group 3 patients had lower valvuloarterial impedance (P = 0.03) and lower left ventricular ejection fraction (P = 0.02) by echocardiogram. CMR identified a progressive increase of right and left ventricular chamber from Group 1 to Group 3, and worsening of left ventricular ejection fraction (EF) (40 [31-47] vs. 32 [29-41] vs. 26 [19-33]%; p < 0.01) and right ventricular EF (62 [53-69] vs. 51 [35-63] vs. 30 [24-46]%; p < 0.01). Besides, there was a marked increase in myocardial fibrosis assessed by extracellular volume fraction (ECV) (28.4 [24.8-30.7] vs. 28.2 [26.9-34.5] vs. 31.8 [28.9-35.5]%; p = 0.03) and indexed ECV (iECV) (28.7 [21.2-39.1] vs. 28.8 [25.4-39.9] vs. 44.2 [36.4-51.2] ml/m², respectively; p < 0.01) from Group 1 to Group 3.

Conclusions

Higher levels of BNP and hsTnI in LFLG-AS patients are associated with worse multi-modality evidence of cardiac remodeling and fibrosis.

Early Change in Area Strain Detected by 3D Speckle Tracking Is Associated With Subsequent Cardiotoxicity in Patients Treated With Low Doses of Anthracyclines

Objective

To evaluate the prognostic impact of the parameters of myocardial deformation using three-dimensional speckle tracking echocardiography (3DSTE) in patients with breast cancer who underwent chemotherapy with low doses of anthracyclines.

Background

Chemotherapy-related cardiotoxicity has an important prognostic impact on cancer survivors. Three-dimensional STE has revealed more consistent data than two-dimensional techniques and may represent a more accurate tool in the evaluation of myocardial function in patients who underwent chemotherapy.

Methods

We evaluated patients with breast cancer who were treated with anthracyclines (associated or not with trastuzumab) in five stages: baseline, after cumulative doses of 120 and 240 mg/m² of doxorubicin, and then, after 6 months and at least 1 year after anthracyclines. Ultrasensitive troponin I (US-TnI) and a standard echocardiography study were performed at each stage. We analyzed left ventricular ejection fraction (LVEF) by Simpson's method, two-dimensional speckle tracking (2DSTE) with longitudinal and radial strain values, and 3DSTE with longitudinal, radial, and circumferential strain as well as twist, torsion, rotation, and three-dimensional global area strain (3DGAS). Cardiotoxicity was defined as a decrease in LVEF by more than 10 percentage points to a value lower than 53%.

Results

We evaluated 51 female patients who were aged 50.6 ± 11 years. After the cumulative dose of 240 mg/m² of doxorubicin, US-TnI was increased (>34 pg/ml) in 21 patients (45%, p > 0.001), LVEF remained unchanged (p = 0.178), while 2DSTE longitudinal strain was decreased (from −17.8% to −17.1%, p < 0.001) and 3DSTE detected changes in longitudinal, radial, circumferential, and area strain. After a lower cumulative dose of doxorubicin (120 mg/m²), 3DGAS (p < 0.001) was the only parameter that was changed. In the follow-up, 7 (13%) patients presented a decrease in LVEF. Three-dimensional GAS early changed to abnormal values was the only variable associated with a subsequent decrease in LVEF (definitive cardiotoxicity).

Conclusion

In patients with breast cancer, 3DSTE detected early changes in area strain after very low doses of doxorubicin. The 3DGAS early changed to abnormal values was associated with a subsequent decrease in LVEF, representing a promising technique to predict chemotherapy-induced cardiomyopathy.

Cardiopulmonary exercise test in patients with refractory angina: functional and ischemic evaluation

OBJECTIVES

Refractory angina (RA) is a chronic condition clinically characterized by low effort tolerance; therefore, physical stress testing is not usually requested for these patients. Cardiopulmonary exercise testing (CPET) is considered a gold standard examination for functional capacity evaluation, even in submaximal tests, and it has gained great prominence in detecting ischemia. The authors aimed to determine cardiorespiratory capacity by using the oxygen consumption efficiency slope (OUES) in patients with refractory angina. The authors also studied the O₂ pulse response by CPET and the association of ischemic changes with contractile modifications by exercise stress echocardiography (ESE).

METHODS

Thirty-one patients of both sexes, aged 45 to 75 years, with symptomatic (Canadian Cardiovascular Society class II to IV) angina who underwent CPET on a treadmill and exercise stress echocardiography on a lower limb cycle ergometer were studied. ClinicalTrials.gov: NCT03218891.

RESULTS

The patients had low cardiorespiratory capacity (OUES of 1.74 ± 0.4 L/min; 63.9±14.7% of predicted), and 77% of patients had a flattening or drop in O₂ pulse response. There was a direct association between Heart Rate (HR) at the onset of myocardial ischemia detected by ESE and HR at the onset of flattening or drop in oxygen pulse response detected by CPET (R = 0.48; p = 0.019).

CONCLUSION

Patients with refractory angina demonstrate low cardiorespiratory capacity. CPET shows good sensitivity for detecting abnormal cardiovascular response in these patients with a significant relationship between flattening O₂ pulse response during CEPT and contractile alterations detected by exercise stress echocardiography.

Multimodality imaging and systemic biomarkers in classical low-flow low-gradient aortic stenosis: key findings for cardiac remodeling evaluation

Background

Elevated levels of troponin I (hsTnT) and B-type natriuretic peptide (BNP) have been related with poor prognosis in patients with LFLG-AS. Biomarkers are less expensive, more practical and more accessible than imaging tests, so their use can be an alternative to imaging in the evaluation of patients with LFLG-AS.

Purpose

The aim of the present study is to assess multimodality imaging findings according to systemic biomarkers (i.e. hsTnT and BNP) in Low-Flow, Low-Gradient Aortic Stenosis (LFLG-AS) and reduced left ventricular ejection fraction (LVEF) patients.

Methods

Prospective study with LFLG-AS patients (LVEF &lt;50%, aortic valve area ≤1,0 cm2 and mean gradient &lt;40 mmHg) that underwent hsTNnT, BNP, cardiac magnetic resonance (CMR) with T1 mapping and 2 dimensional echocardiogram (2DEcho). All patients also underwent dobutamine stress echocardiogram to define aortic stenosis severity. Patients were divided into 3 groups according to BNP and hsTnT levels: Group 1: BNP and hsTnT levels below median (BNP &lt;395 pg/ml and TnI-Ultra &lt;0.042 ng/ml); Group 2: BNP or hsTnT higher than median; and Group 3: both hsTnT and BNP higher than median.

Results

49 patients with LFLG-AS were included (Group 1: 17 patients, Group 2: 14 patients and Group 3: 18 patients). Clinical characteristics (including risk scores) were not able to stratify these groups. Patients with elevation of both biomarkers had lower valvuloarterial impedance (P=0.03), lower LVEF (P=0.02), less moderate/severe mitral (P=0.01) and tricuspid regurgitation (P&lt;0.01) by 2DEcho. CMR identified a progressive increase (from Group 1 to 3) of right and left chamber volumes; reduction in right and left ejection fraction and a marked increase in myocardial fibrosis assessed by extracellular volume (ECV) and indexed extracellular volume (iECV) (Figure 1).

Conclusion

Higher levels of BNP and hsTnT in LFLG-AS patients were associated with worse multi-modality imaging parameters and can be a surrogate of cardiac remodeling.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): No funding

Can the atrial septal defect size in newborn patient predict spontaneous closure?

Funding Acknowledgements

Type of funding sources: None.

onbehalf

Hospital Albert Eisntein"s pediatric echocardiogram team

Can atrial septal defect size in newborn predict spontaneous closure?

Introduction

Spontaneous closure of atrial septal defect (ASD) has been reported to occur in 33%-75% of patients. Factors that influence spontaneous closure are size of the ASD and age of the patients.

Purpose

We aimed to investigate if the diameter of ASD measured by echocardiogram in the newborn can anticipate clinical outcome and predict spontaneous closure.

Methods

We reviewed 1012 two-dimensional echocardiograms (2DE) performed in the first days of life of newborn at our hospital from January 2015 to December 2019 with ASD or patent foramen ovale (PFO) as initial diagnoses. The exclusion criteria were associated congenital heart disease, except ventricular septal defect and patent ductus arteriosus both without repercussion. 153 newborns with ASD or PFO in the first 2DE were included in this study. The individual data collected were age at the exam, birth weight, gestational age, height by birth, ASD diameter, total diameter of atrial septum and Septum/ASD ratio (Table 1). The results were expressed as mean ± SD, or percentage. Comparisons of continuous variables between groups of patients were performed using the Student T test. Statistical significance was determined by p &lt;0,05. The newborn was grouped according to the observation or not of spontaneous closure.

Results

ASD or PFO was found in 153 newborns. 60 had PFO, spontaneous closure was reported in 38 (63%). 93 had ASD in the first 2DE, spontaneous closure was reported in 41 (44%). The mean age of diagnosis was 3,37 ±4,39 days of life. The diameter of the ASD in the first exam and the septum/ASD ratio were associated with spontaneous closure. There was no association between spontaneous closure of ASD and birth weight or gestational age in this studied group.

Conclusion

The ASD diameter obtained at the first 2DE in the first days of life was associated with spontaneous closure of the defect.

Table 1 Non-closure group (N = 52) Closure group (N= 41) P Age at the exam (days) 3,48 (±4,52) 3,2 (±4,27) 0,78 Birth weight (grams) 2459,85 (±1098,79) 2350,12 (±1247,70) 0,65 Gestational age (weeks) 34,88 (±5,17) 34,54 (±5,10) 0,75 Height by birth (cm) 44,46 (±6,81) 43,67 (±6,77) 0,57 ASD diameter (mm) 3,66 (± 2,66 (±0,57) &lt;0,01 Septum diameter (mm) 18,74 (±3,9) 18,92(±4,51) 0,83 Septum/ ASD ratio 5,74 (±2,38) 7,28 (±1,96) &lt;0,01 cm = centimeter, mm = millimeter, ASD = atrial septal defect. Unit: Mean and standard deviation.

Usefulness of speckle tracking echocardiography and biomarkers for detecting acute cellular rejection after heart transplantation

BACKGROUND

Acute cellular rejection (ACR) is a major complication after heart transplantation. Endomyocardial biopsy (EMB) remains the gold standard for its diagnosis, but it has concerning complications. We evaluated the usefulness of speckle tracking echocardiography (STE) and biomarkers for detecting ACR after heart transplantation.

METHODS

We prospectively studied 60 transplant patients with normal left and right ventricular systolic function who underwent EMB for surveillance 6 months after transplantation. Sixty age- and sex-matched healthy individuals constituted the control group. Conventional echocardiographic parameters, left ventricular global longitudinal, radial and circumferential strain (LV-GLS, LV-GRS and LV-GCS, respectively), left ventricular systolic twist (LV-twist) and right ventricular free wall longitudinal strain (RV-FWLS) were analyzed just before the procedure. We also measured biomarkers at the same moment.

RESULTS

Among the 60 studied patients, 17 (28%) had severe ACR (grade ≥ 2R), and 43 (72%) had no significant ACR (grade 0 - 1R). The absolute values of LV-GLS, LV-twist and RV-FWLS were lower in transplant patients with ACR degree ≥ 2 R than in those without ACR (12.5% ± 2.9% vs 14.8% ± 2.3%, p=0.002; 13.9° ± 4.8° vs 17.1° ± 3.2°, p=0.048; 16.6% ± 2.9% vs 21.4%± 3.2%, p < 0.001; respectively), while no differences were observed between the LV-GRS or LV-GCS. All of these parameters were lower in the transplant group without ACR than in the nontransplant control group, except for the LV-twist. Cardiac troponin I levels were significantly higher in patients with significant ACR than in patients without significant ACR [0.19 ng/mL (0.09-1.31) vs 0.05 ng/mL (0.01-0.18), p=0.007]. The combination of troponin with LV-GLS, RV-FWLS and LV-Twist had an area under curve for the detection of ACR of 0.80 (0.68-0.92), 0.89 (0.81-0.93) and 0.79 (0.66-0.92), respectively.

CONCLUSION

Heart transplant patients have altered left ventricular dynamics compared with control individuals. The combination of troponin with strain parameters had higher accuracy for the detection of ACR than the isolated variables and this association might select patients with a higher risk for ACR who will benefit from an EMB procedure in the first year after heart transplantation.

P697 Left ventricular non compaction highlighted by three-dimensional and speckle tracking echocardiography

Introduction

Left ventricular non-compaction (LVNC) is a relatively new cardiomyopathy, first reported by Chin et al. in 1990. Since then, much has been learned about this entity, but until now, there are some limitations for the diagnosis of this disease. Cardiac Magnetic Resonance Imaging is considered the gold standard for the diagnosis of LVNC, but echocardiography remains the first line imaging modality due to its availability and cost efficacy.

Case report

In this case, we report a case of an asymptomatic 21 years old young male with no personal or familiar history of cardiomyopathies. Two dimensional echocardiography (2D Echo) evidenced increased left ventricular trabeculation in the apical segments of lateral and anterior walls and a non compacted myocardium/ (compacted + non compacted myocardium) ratio of 0,33, compatible with LVNC according to Chin´s criteria. 3D Echo provided more detailed LV morphology analysis and 3D Echo Color Doppler evidenced ventricular flow within the intraventricular recesses. Strain analysis by speckle tracking (STE) evidenced global longitudinal strain = - 17% (Normal values &lt; -18%), probably related to an incipient systolic dysfunction not evidenced by the evaluation of left ventricular ejection fraction by 2D Echo.

Conclusions

This case illustrates new echocardiographic modalities for LVNC diagnosis. 3D Echo and STE are new technologies that may play an incremental role in the evaluation of LVNC but need further investigation and validation.

Abstract P697 Figure.

1102 Rare association of left ventricular non-compaction and hypertrophic cardiomyopathy

Background

LVNC and HCM are cardiomyopathies with distinct clinical presentation that may present common genetic mutations. Some studies suggest a common genetic basis between HCM and LVNC and the possibility of a phenotypic association of these two cardiomyopathies in the same patient.

Case report

A 39 year old man was referred to our hospital with syncope. His past medical history was unremarkable. His father died of sudden death, at age 49, without investigation of Left ventricular non compaction (LVNC) or Hypertrophic cardiomyopathy (HCM). Physical examination was unremarkable. Electrocardiogram showed sinus rhythm with left chambers overload and isolated ventricular extrasystoles. Transthoracic Echocardiogram (TTE) evidenced significant left ventricular (LV) hypertrophy predominantly in the apical region and inferolateral wall, in the absence of a significant intraventricular gradient at rest and after provocative maneuvers, with preserved LV function, suggesting non-obstructive HCM. Cardiac magnetic resonance imaging (CMRI) showed LV hypertrophy predominantly in the lateral wall, with a maximum thickness of 35 mm, no signs of left ventricular outflow tract (LVOT) obstruction and prominent apical trabeculation, compatible with the association of LVNC and HCM. A genetic test was performed on this patient with inconclusive results.

Conclusions

The association of diagnostic criteria in cardiac imaging tests (TTE and CMRI) compatible with LVNC and HCM in the same patient is uncommon. This patient shows an infrequent location of the most prominent hypertrophy in the inferolateral wall.This case highlights the importance of integrating cardiac imaging methods in the diagnosis of these two disctinct and rare cardiomyopathies.

Legend Figure 1: 2D TTE evidencing prominent hypertropfhy and intraventricular recesses at apical region and inferolateral wall (red arrows), abnormalities suggesting HCM and LVNC at LV apex (blue arrows) in Paraesternal Long Axis (A and B), Short Axis View (C to F), Apical 4 Chambers (G and H) and Apical 2 Chambers View (I and H). Speckle tracking analysis evidencing incipient LV systolic dysfunction by reduced global longitudinal strain (GLS:-8,9%) despite the preserved LVEF (K to N). CMR evidencing findings compatible with the association of LVNC (blue arrows) and HCM (red arrow) in 4 Chambers (O and P), 2 Chambers (Q and R) and Short Axis Views (S to V).

Abstract 1102 Figure 1

1186 Three-dimensional analysis of right ventricle strain in transplanted hearts and rejection: an ongoing prospective study

Background

The main obstacle for success after heart transplantation is graft rejection, since is mainly asymptomatic and diagnosed by endomyocardial biopsy (EMB). New echocardiographic technologies could bring benefits to that population if subtle changes in heart mechanics were related to an incipient state of rejection.

Purpose

To quantify echocardiographic parameters of right ventricle strain and volumes by a semi-automated offline software and to identify the presence of any relation between those findings and the histopathologic diagnose of rejection.

Methods

a prospective cohort of 35 postoperative heart transplant patients who were submitted to echocardiographic evaluation up to six hours after EMB, including two-dimensional chamber quantification of left ventricular (LV) volumes and ejection fraction; conventional and tissue Doppler measurements were used for flow and functional analysis. Offline assessment of the right ventricle (RV) was made by TOMTEC software, with the acquisition of RV volumes (EDV, ESV, SV) and ejection fraction, TAPSE, FAC and three-dimensional(3D) RV free wall and septal strain using speckle tracking. EMB results were classified as positive for cellular rejection if graded as 2R (two or more interstitial infiltrate spots and myocyte damage) and positive for humoral rejection if they show any response by immunofluorescence assay.

Results

We studied 35 patients, aged 50 ±11, 21 male (67%), totaling 58 examinations, and then we made two analysis of EMB: one in two groups regarding cellular rejection (53 negative and 5 positive) and other regarding humoral rejection (50 negative and 8 positive). RVEDV was higher in the cellular rejection group (112,5 ± 29,6 ml) compared to those with negative biopsy (86,8 ± 24,7 mL; p = 0,01). RV stroke volume showed a similar behavior (53,5 ± 22,3 mL vs. 34,5 ± 11,3 mL; p &lt; 0,01). Regarding humoral rejection by immunofluorescence, patients who tested positive showed lower RVEDV (79,5 ± 10,5 mL vs. 90,57 ± 27,31 mL; p = 0,02) and RVESV (45,53 ± 6,33 mL vs. 53,87 ± 19,87 mL; p = 0,01). RV free wall strain was lower in the group with positive immunofluorescence (-18,35 ± 2,79% vs. -15,34 ± 5,35%; p = 0,01). Regarding 2D measurements , interventricular septal (11,5 ± 1,06 mm vs. 10,56 ± 1,38 mm; p = 0,02) and left ventricular posterior wall (10,75 ± 1,03 mm vs. 10,04 ± 1,1 mm; p = 0,05) were also thicker in the group with positive immunofluorescence for rejection.

Conclusion

Both cellular and humoral rejection after heart transplantation are associated to increased 3D RV volumes whereas a decrease in RV free wall strain is only observed in humoral rejection; in patients with positive immunofluorescence results a significant increase is seen for septal and posterior wall thickness.

P1396 Three-dimensional cardiac mechanics for prediction of events in Chagas disease

Introduction

Chagas disease (CD) is an endemic infectious disease that still remains a great economic burden. Three-dimensional speckle tracking (3D STE) may play a role in the evaluation of CD. We assessed the hypothesis that 3D STE may predict clinical events in patients with CD.

Methods

This was a convenience sample. Patients with any systemic disease were excluded. Eight hundred and eight patients with CD were evaluated but only seventy-two were included. Clinical, electrocardiographic and comprehensive conventional and 3D echocardiography were performed. Patients were followed up for thirty-six up to sixty months. Clinical events were defined as hospitalization for heart failure, ventricular arrhythmias and cardiovascular death.

Results

Seventy-two patients were enrolled in three groups: Group 1 (G1), patients with left ventricular ejection fraction (LVEF) &lt; 0.35 (N = 22); Group 2 (G2), LVEF between 0.35 and 0.55 (N = 22); Group 3 (G3), normal LVEF (N = 28). Gender distribution, mean age, anthropometric variables and risk factors were similar between the groups. 2D STE feasibility was 99.5, 99 and 100% in G1, G2 and G3. 3D Longitudinal strain feasibility was 93, 89 e 88% in G1, G2 and G3. Interobserver and intraobserver variabilities (Blant-Altman) for longitudinal (2D and 3D GLS), circumferential (3D GCS), radial (3D GRS) and area strain (3D AS) are displayed in Table 1.

Hospitalization was related do indexed left atrium volume (p = 0,03) in G1. In G2, non-sustained ventricular tachycardia were related to 2D GLS values (p = 0,04); all clinical events were related do diastolic function (p = 0,30). In G1 and G2, hospitalization was related do indexed left atrium volume (p = 0,01); all clinical events were related do diastolic function (p = 0,004) and 3D LVEF (p = 0,02). 3D STE parameters were not related to clinical events.

Conclusions

In conclusion, 3D STE in patients with CD appears to be an accurate, reproducible and promising method but was not related to clinical events.

Table 1 INTEROBSERVER INTRAOBSERVER 2D GLS 0.96 ± 0.04 0.90 ± 0.08 3D GLS 0.92 ± 0.07 0.93 ± 0.10 3D GCS 0.88 ± 0.07 0.82 ± 0.15 3D AS 0.93 ± 0.05 0.90 ± 0.05 3D RS 0.85 ± 0.05 0.84 ± 0.11 Table 1. Interobserver and intraobserver variabilities for longitudinal (2D and 3D GLS), circumferential (3D GCS), radial (3D GRS) and area strain (3D AS).

P6483Predictors of contractile reserve on dobutamine stress echocardiography in patients with classical low-flow, low-gradient aortic stenosis

Background

There is a lack of information on factors that influence contractile reserve (CR) on dobutamine stress echocardiography (DSE) in patients with classical low-flow, low-gradient aortic stenosis (LFLG-AS).

Purpose

This study sought to evaluate the predictors of CR in patients with LFLG-AS.

Methods

Prospective study including 43 consecutive LFLG-AS patients (aortic valve area [AVA] ≤1.0 cm2, mean transaortic gradient <40 mmHg, left ventricular ejection fraction [LVEF] <50%) with true severe aortic stenosis. All patients underwent dobutamine stress echocardiography and T1-mapping cardiac magnetic resonance (CMR). CR was defined as an increase ≥20% in the left ventricular stroke volume at peak stress. Patients with pseudo-severe aortic stenosis were excluded.

Results

All of the patients in the study had degenerative aortic stenosis, with a median age of 67 [60–74] years, most of them being male (83.7%). A high prevalence of comorbidities was found, highlighted by diabetes (42%), hypertension (70%), atrial fibrillation (25%) and coronary artery disease (38%). Mean transaortic gradient was 25 [20–33] mmHg, AVA was 0.88 [0.68–0.95] cm2, LVEF was 35 [28–43]% and 32.6% had moderate/severe functional mitral regurgitation. CMR myocardium extracellular volume fraction (ECV) was 28.8 [26.3–33.0] %, indexed ECV was 35.4 [25.0–41.2] ml/m2, 32.6% had positive transmural delayed-enhancement images and 25.6% had positive mesocardial delayed-enhancement images. On DSE, 30 patients (69.7%) had CR and 13 patients (30.3%) had no CR. Global longitudinal strain was 10 [7–12] %, Δ indexed flow rate was 25 [3–38] ml/m2.seg and Δ mean gradient was 10 [3–16] mmHg. By multivariate analysis, moderate/severe functional mitral regurgitation (HR 0.122, 95% CI 0.020–0.759, p=0.024) and AVA (HR 0.606, 95% CI 0.396–0.925, p=0.020 [for each increase of 0.05 cm2]) were the only factors associated with CR. ECV, indexed ECV and positive transmural or mesocardial delayed-enhancement images were not associated with CR in the univariate analysis.

Conclusions

In our study, the absence of moderate/severe functional mitral regurgitation and AVA were predictors of CR on DSE in patients with LFLG-AS. As AVA was smaller in patients with CR, our finding contradicts the hypothesis that more severe aortic stenosis could also contribute to the lack of CR. Other possible factors that are surrogate of myocardium fibrosis, as ECV, indexed ECV and positive delayed-enhancement images, were not associated with the absence of CR.

Acknowledgement/Funding

FAPESP

P2515Cardiac rehabilitation in patients with refractory angina: preliminary results

Introduction

Refractory angina (RA) implies important impairment of quality of life. Cardiac rehabilitation (CR) is still not recommended by guidelines due to few evidence regarding its effects in this population. This study evaluated the impact of CR on physical performance and on angina/ischemia threshold.

Methods

36 RA patients undergoing optimal medical therapy were randomly assigned to a 12-week exercise based CR program or stablished clinical follow-up (CF). Clinical evaluation, exercise bicycle stress echocardiography (SE) and cardiopulmonary exercise testing (CP) were performed before and after the protocol. CR group performed in-hospital exercise sessions, and the aerobic training prescription was based on CP parameters or ischemia/ angina threshold. Each CR class was 60 min in duration (5min warm-up, 30min aerobic and 5min cooldown, 15min low load resistance training and 5min stretching). Bonferroni multiple comparison and t test were used in statistical analysis.

Results

Baseline characteristics didn't differ between groups. In RC group, 40% presented CCS 2, 25% CCS 3 and 35% CCS 4, while in CF group, 41%, 23.5% and 35.5%, respectively (p=0.5). There was no change in CCS between groups after intervention. CR group presented an increase in ischemic threshold in SE when compared to CF group (234.6±87.9s to 293.8±130.9 s vs. 200.9±78.6s to 203.7±93.7s, p=0.044), increase in angina threshold in SE (156.00±62.2s to 260.1±152.8s vs. 190.6±96.6s to 152.9±76, 7s, p=0.041) and increase in CP total duration (347.9±143.2s to 489.8±170.2s vs. 331.7±128.5s to 323.5±101.0s, p=0,016).

Baseline characteristics in both groups Variables CR group (n=19) CF group (n=17) p Male sex (%) 63.2 58.8 0.8 Age, years (mean ± SD) 61.2±8.7 62.9±8.8 0.6 LVEF, % (mean ± SD) 55.7±7.3 50.0±10.4 0.08 SBP, mmHg (mean ± SD) 125.6±18.0 122.6±14.5 0.6 DBP, mmHg (mean ± SD) 77.5±9.6 76.2±13,1 0.7 HR, bpm (mean ± SD) 60.5±6.2 60.6±7.1 0.9 BMI, kg/m2 (mean ± SD) 28.8±4.1 26.1±10.9 0.4 Fasting glucose, mg/dl (mean ± SD) 136.4±33.6 153.6±64.7 0.3 HBA1C, % (mean ± SD) 6.8±1.2 7.2±1.6 0.4 LDL-c, mg/dl (mean ± SD) 77.8±29.0 84.7±28.6 0.5

Results

CR seems to be an effective adjuvant treatment in RA, increasing ischemia and angina threshold, improving physical performance.

Acknowledgement/Funding

FAPESP

Identification of passion fruit (Passiflora edulis) chromosomes using BAC-FISH

Passiflora edulis, the yellow passion fruit, is the main crop from the Passiflora genus, which comprises 525 species with its diversity center in South America. Genetic maps and a BAC (bacterial artificial chromosome) genomic library are available, but the nine chromosome pairs of similar size and morphology (2n = 18) hamper chromosome identification, leading to different proposed karyotypes. Thus, the aim of this study was to establish chromosome-specific markers for the yellow passion fruit using single-copy and repetitive sequences as probes in fluorescent in situ hybridizations (FISH) to allow chromosome identification and future integration with whole genome data. Thirty-six BAC clones harboring genes and three retrotransposons (Ty1-copy, Ty3-gypsy, and LINE) were selected. Twelve BACs exhibited a dispersed pattern similar to that revealed by retroelements, and one exhibited subtelomeric distribution. Twelve clones showed unique signals in terminal or subterminal regions of the chromosomes, allowing their genes to be anchored to six chromosome pairs that can be identified with single-copy markers. The markers developed herein will provide an important tool for genomic and evolutionary studies in the Passiflora genus.

Relation of mitral valve morphology to surgical repair results in patients with mitral valve prolapse: A three-dimensional transesophageal echocardiography study

BACKGROUND

The identification of predictors of mitral valve (MV) repair results is important for quality improvement in cardiac surgery. The aim of this study was to evaluate the relationship between MV morphological quantification by three-dimensional (3D) transesophageal echocardiography and mitral repair results.

METHODS

Fifty-four patients with MV prolapse who were submitted to surgical repair were divided into 2 groups according to their postoperative mitral regurgitation (MR) degree (group 1, grade 0-I MR; group 2, ≥grade II MR). Morphological parameters related to the mitral ring, dimension of leaflets and prolapse, coaptation line, distance from papillary muscles to the leaflet border and valve angles were analyzed by 3D MV quantification. Cardiac remodeling and MR quantitative parameters were also evaluated.

RESULTS

There was no correlation between 3D MV quantification and surgical results; a multivariate analysis did not show an association between morphological parameters and surgical outcome. The distance from the posteromedial papillary muscle to the leaflet border was higher (P = .038) in patients with ≥grade II postoperative MR. The left atrial diameter, left ventricular end-systolic diameter, left ventricular end-diastolic and end-systolic volumes were larger in patients with a significant residual MR (P < .05).

CONCLUSION

Three-dimensional MV quantification did not predict the postoperative MR grade; however, the distance from the posteromedial papillary muscles to the leaflet border may be related to suboptimal repair results. Furthermore, excessive cardiac remodeling was related to postoperative MR ≥ grade II, what could suggest a potential benefit of early surgical treatment.

Activity of Antarctic fungi extracts against phytopathogenic bacteria

This study aims to obtain secondary metabolites extracts from filamentous fungi isolated from soil and marine sediments from Antarctic ecosystems and to assess its potential antibacterial activity on Xanthomonas euvesicatoria and Xanthomonas axonopodis pv. passiflorae (phytopathogenic bacteria causing diseases in pepper and tomato and passionfruit, respectively). Among the 66 crude intracellular and extracellular extracts obtained from fungi recovered from soil and 79 obtained from marine sediment samples, 25 showed the ability to prevent the growth of X. euvesicatoria in vitro and 28 showed the ability to prevent the growth of X. axonopodis pv. passiflorae in vitro. Intracellular and extracellular extracts from soil fungi inhibited around 97% of X. euvesicatoria and 98% of X. axonopodis pv. passiflorae at 2·1 mg ml^-1 . The average inhibition rates against X. euvesicatoria and X. axonopodis pv. passiflorae for intracellular and extracellular extracts from marine sediments fungi were around 96 and 97%, respectively, at 3·0 mg ml^-1 . Extracts containing secondary metabolites with antimicrobial activity against X. euvesicatoria and X. axonopodis pv. passiflorae were obtained, containing possible substitutes for the products currently used to control these phytopathogens.

SIGNIFICANCE AND IMPACT OF THE STUDY

Micro-organisms from extreme ecosystems, such as the Antarctic ecosystem, need to survive in harsh conditions with low temperatures, low nutrients and high UV radiation. Micro-organisms adapt to these conditions evolving diverse biochemical and physiological adaptations essential for survival. All this makes these micro-organisms a rich source of novel natural products based on unique chemical scaffolds. Discovering novel bioactive compounds is essential because of the rise in antibiotic-resistant micro-organisms and the emergence of new infections. Fungi from Antarctic environments have been proven to produce bioactive secondary metabolites against various micro-organisms, but few studies have shown activity against Xanthomonas phytopathogens.

New equation for prediction of reverse remodeling after cardiac resynchronization therapy

OBJECTIVES

To integrate data from two-dimensional echocardiography (2D ECHO), three-dimensional echocardiography (3D ECHO), and tissue Doppler imaging (TDI) for prediction of left ventricular (LV) reverse remodeling (LVRR) after cardiac resynchronization therapy (CRT). It was also compared the evaluation of cardiac dyssynchrony by TDI and 3D ECHO.

METHODS

Twenty-four consecutive patients with heart failure, sinus rhythm, QRS ≥ 120 msec, functional class III or IV and LV ejection fraction (LVEF) ≤ 0.35 underwent CRT. 2D ECHO, 3D ECHO with systolic dyssynchrony index (SDI) analysis, and TDI were performed before, 3 and 6 months after CRT. Cardiac dyssynchrony analyses by TDI and SDI were compared with the Pearson's correlation test. Before CRT, a univariate analysis of baseline characteristics was performed for the construction of a logistic regression model to identify the best predictors of LVRR.

RESULTS

After 3 months of CRT, there was a moderate correlation between TDI and SDI (r = 0.52). At other time points, there was no strong correlation. Nine of twenty-four (38%) patients presented with LVRR 6 months after CRT. After logistic regression analysis, SDI (SDI > 11%) was the only independent factor in the prediction of LVRR 6 months of CRT (sensitivity = 0.89 and specificity = 0.73). After construction of receiver operator characteristic (ROC) curves, an equation was established to predict LVRR: LVRR =-0.4LVDD (mm) + 0.5LVEF (%) + 1.1SDI (%), with responders presenting values >0 (sensitivity = 0.67 and specificity = 0.87).

CONCLUSIONS

In this study, there was no strong correlation between TDI and SDI. An equation is proposed for the prediction of LVRR after CRT. Although larger trials are needed to validate these findings, this equation may be useful to candidates for CRT.

Report of a Large Brazilian Family With a Very Attenuated Form of Hunter Syndrome (MPS II)

Hunter syndrome, or Mucopolysaccharidosis type II (MPS II), is a rare X-linked recessive disorder caused by a deficiency of the lysosomal enzyme iduronate-2-sulfatase (IDS). The phenotypic spectrum varies from severe to attenuated clinical forms. We report a large Brazilian family with 16 affected individuals exhibiting a very attenuated form of MPS II. Fourteen female carriers were also identified. Twelve affected male patients, whose ages ranged from 1 to 35 years, were examined. Molecular analysis showed a novel missense mutation (p.A77D) in the IDS gene, confirming the diagnosis. Nine of the family members presented some degree of heart damage, though only the proband became symptomatic and required heart transplantation. One 19-year-old adult and 1-year-old twin boys each had a normal echocardiogram. Short stature was found in two adults while macrocephaly was found in one; the remaining adults had anthropometric measures within normal range. All affected adults had normal cognitive development and were able to perform normal daily activities, except one who had mild learning disability. Two patients died due to natural causes beyond 70 years of age. The female carriers did not present any signs of disease. In this large family with a mild form of MPS II and variable degree of clinical manifestations, it is noteworthy that several affected individuals have remained asymptomatic even at advanced age and even without enzyme replacement therapy.

Genetic diversity and a PCR-based method for Xanthomonas axonopodis detection in passion fruit

Xanthomonas axonopodis pv. passiflorae causes bacterial spot in passion fruit. It attacks the purple and yellow passion fruit as well as the sweet passion fruit. The diversity of 87 isolates of pv. passiflorae collected from across 22 fruit orchards in Brazil was evaluated using molecular profiles and statistical procedures, including an unweighted pair-group method with arithmetical averages-based dendrogram, analysis of molecular variance (AMOVA), and an assigning test that provides information on genetic structure at the population level. Isolates from another eight pathovars were included in the molecular analyses and all were shown to have a distinct repetitive sequence-based polymerase chain reaction profile. Amplified fragment length polymorphism technique revealed considerable diversity among isolates of pv. passiflorae, and AMOVA showed that most of the variance (49.4%) was due to differences between localities. Cluster analysis revealed that most genotypic clusters were homogeneous and that variance was associated primarily with geographic origin. The disease adversely affects fruit production and may kill infected plants. A method for rapid diagnosis of the pathogen, even before the disease symptoms become evident, has value for producers. Here, a set of primers (Xapas) was designed by exploiting a single-nucleotide polymorphism between the sequences of the intergenic 16S-23S rRNA spacer region of the pathovars. Xapas was shown to effectively detect all pv. passiflorae isolates and is recommended for disease diagnosis in passion fruit orchards.