Implementing focused echocardiography and AI-supported analysis in a population-based survey in Lesotho: implications for community-based cardiovascular disease care models

In settings where access to expert echocardiography is limited, focused echocardiography, combined with artificial intelligence (AI)-supported analysis, may improve diagnosis and monitoring of left ventricular hypertrophy (LVH). Sixteen nurses/nurse-assistants without prior experience in echocardiography underwent a 2-day hands-on intensive training to learn how to assess parasternal long axis views (PLAX) using an inexpensive hand-held ultrasound device in Lesotho, Southern Africa. Loops were stored on a cloud-drive, analyzed using deep learning algorithms at the University Hospital Basel, and afterwards confirmed by a board-certified cardiologist. The nurses/nurse-assistants obtained 756 echocardiograms. Of the 754 uploaded image files, 628 (83.3%) were evaluable by deep learning algorithms. Of those, results of 514/628 (81.9%) were confirmed by a cardiologist. Of the 126 not evaluable by the AI algorithm, 46 (36.5%) were manually evaluable. Overall, 660 (87.5%) uploaded files were evaluable and confirmed. Following short-term training of nursing cadres, a high proportion of obtained PLAX was evaluable using AI-supported analysis. This could be a basis for AI- and telemedical support in hard-to-reach areas with minimal resources.

Right Heart Structure and Function after Electrical Cardioversion for Atrial Fibrillation

INTRODUCTION

Atrial fibrillation (AF) adversely impacts right ventricular (RV) and right atrial (RA) structure and function. There are limited data on these changes after electrical cardioversion (ECV) and the relative contribution of heart rate to evaluate the immediate (1-2 h) and short-term (4-6 weeks) changes in right cardiac chamber dimensions and RV function after ECV in patients with persistent AF.

METHODS

Right cardiac chamber dimensions and RV function were measured in 64 patients using transthoracic echocardiography 1-2 h before, immediately after, and 4-6 weeks after ECV. Associations between changes in right-heart measures and rhythm status at follow-up were assessed using linear regression models.

RESULTS

For patients who remained in sinus rhythm 4-6 weeks after ECV (n = 48), median fractional area change (FAC) at baseline, immediately after ECV, and 4-6 weeks after ECV were 39 (Q1:35, Q3:42) %, 42 (Q1:39, Q3:46) %, 46 (Q1:43, Q3:49) % (p < 0.01); median tricuspid annular plane systolic excursion (TAPSE) values at the same time points were 18 (Q1:17, Q3:20) mm, 20 (Q1:18, Q3:23) mm, and 24 (Q1:22, Q3:26) mm (p < 0.01), respectively. There was no significant difference in RV end systolic area and RA volume index before and after ECV. However, RV end systolic area and RA volume index decreased significantly after 4-6 weeks from a median of 10 (Q1:8, Q3:13) cm2 to 8 (Q1:7, Q3:10) cm2 (p < 0.01), and from a median of 30 (Q1:24, Q3:36) mL/m2 to 24 (Q1:20, Q3:27) mL/m2 (p < 0.01). Changes in TAPSE were significantly associated with sinus rhythm at follow-up (p = 0.027), changes in FAC showed a strong trend to association with sinus rhythm (p = 0.053), and this was not true for RA measures (p = 0.64).

CONCLUSIONS

Among AF patients who remained in sinus rhythm after ECV, RV function improved immediately after ECV with further improvement at 4-6 weeks following sinus rhythm restoration.

Echocardiographic pattern of left ventricular function recovery in tachycardia-induced cardiomyopathy patients

AIMS

Tachycardia-induced cardiomyopathy (TCM) represents a partially reversible type of cardiomyopathy (CM) that is often underdiagnosed and cardiac chamber remodelling in TCM remains incompletely understood. We aim to explore differences in the dimensions of the left ventricle and functional recovery in patients with TCM compared with patients with other forms of CM.

METHODS AND RESULTS

We identified patients with reduced ejection fraction (≤50%) and/or atrial fibrillation or flutter with a left ventricular ejection fraction that improved from baseline (≥15% in left ventricular ejection fraction at follow-up or normalization of cardiac function with at least 10% improvement). Patients were then divided into two groups: (A) TCM patients and (B) patients with other forms of CM (controls). Two hundred thirty-eight patients were included (31% female, 70 years median age), 127 patients had TCM, and 111 had other forms of CM. Patients with TCM did not significantly improve indexed left ventricular volume (LVEDVI) after treatment (60 [45, 84] mL/m² versus 56 [45, 70] mL/m² , P = ns) compared with controls (67 [54, 81] mL/m² versus 52 [42, 69] mL/m² , P < 0.001). Patients with TCM patients had significantly worse fractional shortening at baseline than controls (15.5 [12, 23] vs. 20 [13, 30], P = 0.01) and higher indexed left atrial volume (LAVI) at baseline than controls (48 [37, 58] vs. 41 [33, 51], P = 0.01) that remained dilated at follow-up (follow-up LAVI 41 [33, 52] mL/m² ). Good predictors of TCM were: normal LVEDVI (LVEDVI < 58 mL/m² (M) and < 52 mL/m² (F)) (odds ratio [OR] 5.2; 95% confidence interval [CI] 2.2-13.3, P < 0.001), fractional shortening < 30% (OR 3.5; 95% CI 1.4-9.2, P = 0.009), LAVI >40 mL/m² (OR 3.4; 95% CI 1.6-7.3, P = 0.001) and normal wall thickness left ventricle (OR 3.2; 95% CI 1.4-7.8, P = 0.008). 54% of patients with TCM demonstrated diastolic dysfunction at follow-up, without differences from controls (54% vs. 43%, P = ns). 21% of patients with TCM showed persistent heart failure symptoms at follow-up compared with 4.5% of controls, P = 0.004.

CONCLUSIONS

TCM patients have a specific pattern of functional recovery with persistent remodelling of the left atria and left ventricle. Several echocardiographic parameters might help identify TCM before treatment.

Hypertensive Heart Disease-The Imaging Perspective

Hypertensive heart disease (HHD) develops in response to the chronic exposure of the left ventricle and left atrium to elevated systemic blood pressure. Left ventricular structural changes include hypertrophy and interstitial fibrosis that in turn lead to functional changes including diastolic dysfunction and impaired left atrial and LV mechanical function. Ultimately, these changes can lead to heart failure with a preserved (HFpEF) or reduced (HFrEF) ejection fraction. This review will outline the clinical evaluation of a patient with hypertension and/or suspected HHD, with a particular emphasis on the role and recent advances of multimodality imaging in both diagnosis and differential diagnosis.

Renal dysfunction and outcome in left ventricular non-compaction

BACKGROUND

While renal function has been observed to inversely correlate with clinical outcome in other cardiomyopathies, its prognostic significance in patients with left ventricular non-compaction cardiomyopathy (LVNC) has not been investigated. The aim of this study was to determine the prognostic value of renal function in LVNC patients.

METHODS

Patients with isolated LVNC as diagnosed by echocardiography and/or magnetic resonance imaging in 4 Swiss centers were retrospectively analyzed for this study. Values for creatinine, urea, and estimated glomerular filtration rate (eGFR) as assessed by the CKD-EPI 2009 formula were collected and analyzed by a Cox regression model for the occurrence of a composite endpoint (death or heart transplantation).

RESULTS

During the median observation period of 7.4 years 23 patients reached the endpoint. The ageand gender-corrected hazard ratios (HR) for death or heart transplantation were: 1.9 (95% confidence interval [CI] 1.4-2.6) for each increase over baseline creatinine level of 30 μmol/L (p < 0.001), 1.6 (95% CI 1.2-2.2) for each increase over baseline urea level of 5 mmol/L (p = 0.004), and 3.6 (95% CI 1.9-6.9) for each decrease below baseline eGFR level of 30 mL/min (p ≤ 0.001). The HR (log2) for every doubling of creatinine was 7.7 (95% CI 3-19.8; p < 0.001), for every doubling of urea 2.5 (95% CI 1.5-4.3; p < 0.001), and for every bisection of eGFR 5.3 (95% CI 2.4-11.6; p < 0.001).

CONCLUSIONS

This study provides evidence that in patients with LVNC impairment in renal function is associated with an increased risk of death and heart transplantation suggesting that kidney function assessment should be standard in risk assessment of LVNC patients.

Cardiovascular imaging following perioperative myocardial infarction/injury

Patients developing perioperative myocardial infarction/injury (PMI) have a high mortality. PMI work-up and therapy remain poorly defined. This prospective multicenter study included high-risk patients undergoing major non-cardiac surgery within a systematic PMI screening and clinical response program. The frequency of cardiovascular imaging during PMI work-up and its yield for possible type 1 myocardial infarction (T1MI) was assessed. Automated PMI detection triggered evaluation by the treating physician/cardiologist, who determined selection/timing of cardiovascular imaging. T1M1 was considered with the presence of a new wall motion abnormality within 30 days in transthoracic echocardiography (TTE), a new scar or ischemia within 90 days in myocardial perfusion imaging (MPI), and Ambrose-Type II or complex lesions within 7 days of PMI in coronary angiography (CA). In patients with PMI, 21% (268/1269) underwent at least one cardiac imaging modality. TTE was used in 13% (163/1269), MPI in 3% (37/1269), and CA in 5% (68/1269). Cardiology consultation was associated with higher use of cardiovascular imaging (27% versus 13%). Signs indicative of T1MI were found in 8% of TTE, 46% of MPI, and 63% of CA. Most patients with PMI did not undergo any cardiovascular imaging within their PMI work-up. If performed, MPI and CA showed high yield for signs indicative of T1MI.Trial registration: https://clinicaltrials.gov/ct2/show/NCT02573532 .

P2Y12 Inhibition in Murine Myocarditis Results in Reduced Platelet Infiltration and Preserved Ejection Fraction

Previous mouse studies have shown the increased presence of platelets in the myocardium during early stages of myocarditis and their selective detection by MRI. Here, we aimed to depict early myocarditis using molecular contrast-enhanced ultrasound of activated platelets, and to evaluate the impact of a P2Y12 receptor platelet inhibition. Experimental autoimmune myocarditis was induced in BALB/c mice by subcutaneous injection of porcine cardiac myosin and complete Freund adjuvant (CFA). Activated platelets were targeted with microbubbles (MB) coupled to a single-chain antibody that binds to the "ligand-induced binding sites" of the GPIIb/IIIa-receptor (=LIBS-MB). Alongside myocarditis induction, a group of mice received a daily dose of 100 g prasugrel for 1 month. Mice injected with myosin and CFA had a significantly deteriorated ejection fraction and histological inflammation on day 28 compared to mice only injected with myosin. Platelets infiltrated the myocardium before reduction in ejection fraction could be detected by echocardiography. No selective binding of the LIBS-MB contrast agent could be detected by either ultrasound or histology. Prasugrel therapy preserved ejection fraction and significantly reduced platelet aggregates in the myocardium compared to mice without prasugrel therapy. Therefore, P2Y12 inhibition could be a promising early therapeutic target in myocarditis, requiring further investigation.

NOX1 mediates metabolic heart disease in mice and is upregulated in monocytes of humans with diastolic dysfunction

AIMS

Microvascular inflammation plays an important role in the pathogenesis of diastolic dysfunction (DD) and metabolic heart disease. NOX1 is expressed in vascular and immune cells and has been implicated in the vascular pathology of metabolic disease. However, its contribution to metabolic heart disease is less understood.

METHODS AND RESULTS

NOX1-deficient mice (KO) and male wild-type (WT) littermates were fed a high-fat high-sucrose diet (HFHS) and injected streptozotocin (75 mg/kg i.p.) or control diet (CTD) and sodium citrate. Despite similar weight gain and increase in fasting blood glucose and insulin, only WT-HFHS but not KO-HFHS mice developed concentric cardiac hypertrophy and elevated left ventricular filling pressure. This was associated with increased endothelial adhesion molecule expression, accumulation of Mac-2-, IL-1β- and NLRP3-positive cells and nitrosative stress in WT-HFHS but not KO-HFHS hearts. Nox1 mRNA was solidly expressed in CD45+ immune cells isolated from healthy mouse hearts, but was negligible in cardiac CD31+ endothelial cells. However, in vitro, Nox1 expression increased in response to LPS in endothelial cells and contributed to LPS-induced upregulation of Icam-1. Nox1 was also upregulated in mouse bone marrow-derived macrophages in response to LPS. In peripheral monocytes from age- and sex-matched symptomatic patients with and without DD, NOX1 was significantly higher in patients with DD compared to those without DD.

CONCLUSIONS

NOX1 mediates endothelial activation and contributes to myocardial inflammation and remodeling in metabolic disease in mice. Given its high expression in monocytes of humans with DD, NOX1 may represent a potential target to mitigate heart disease associated with DD.

TRANSLATIONAL PERSPECTIVE

In their multifactorial pathogenesis, diastolic dysfunction (DD) and heart failure with preserved ejection fraction (HFpEF) still remain poorly understood. They frequently occur in patients with obesity and metabolic syndrome. Microvascular inflammation and dysfunction have recently been recognized as major driving forces. We show that genetic deletion of Nox1 prevents cardiac inflammation, remodeling and dysfunction in metabolic disease in mice and find NOX1 upregulated in peripheral monocytes of patients with DD. These findings add to our understanding how obesity, inflammation and heart disease are linked, which is a prerequisite to find therapeutic strategies beyond the control of co-morbidities in HFpEF.

Designed Ankyrin Repeat Proteins as Novel Binders for Ultrasound Molecular Imaging

Clinical translation of ultrasound molecular imaging will depend on the development of binders that can easily be generated, manufactured and coupled, and that are compatible with in vivo use. We describe targeted microbubbles (MBs) using designed ankyrin repeat proteins (DARPins) as a novel class of such translatable binders. Candidate DARPin binders for vascular cell adhesion molecule 1, an endothelial cell adhesion molecule involved in inflammatory processes, were selected using ribosome display and coupled to MBs. Flow-chamber assays of five MBs carrying high-affinity binders showed selective retention on endothelial cells activated by tumor necrosis factor-α for two binders compared with a MB carrying a control DARPin. In vivo ultrasound molecular imaging in a murine hind-limb inflammation model demonstrated up to a fourfold signal enhancement for three of the five MBs versus control. However, there was no correlation between results from flow-chamber assays and in vivo imaging. Thus, we conclude that ultrasound molecular imaging of inflammation using DARPin binders is feasible per se, but that screening of candidates cannot be accomplished with flow-chamber assays as used in our study.

Intensification of pharmacological decongestion but not the actual daily loop diuretic dose predicts worse chronic heart failure outcome: insights from TIME-CHF

BACKGROUND

Both loop diuretics (LDs) and congestion have been related to worse heart failure (HF) outcome. The relationship between the cause and effect is unknown. The aim of this study was to investigate the interaction between congestion, diuretic use and HF outcome.

METHODS

Six hundred and twenty-two chronic HF patients from TIME-CHF were studied. Congestion was measured by means of a clinical congestion index (CCI). Loop diuretic dose was considered at baseline and month 6. Treatment intensification was defined as the increase in LD dose over 6 months or loop diuretic and thiazide or thiazide-like diuretic co-administration. The end-points were survival and HF hospitalisation-free survival.

RESULTS

High-LD dose at baseline and month 6 (≥ 80 mg of furosemide per day) was not identified as an independent predictor of outcome. CCI at baseline remained independently associated with impaired survival [hazard ratio (HR) 1.34, (95% confidence interval) (95% CI) (1.20-1.50), p < 0.001] and HF hospitalisation-free survival [HR 1.09, 95% CI (1.02-1.17), p = 0.015]. CCI at month 6 was independently associated with HF hospitalisation-free survival [HR 1.24, 95% CI (1.11-1.38), p < 0.001]. Treatment intensification was independently associated with survival [HR 1.75, 95% CI (1.19-1.38), p = 0.004] and HF hospitalisation-free survival [HR 1.69, 95% CI (1.22-2.35), p = 0.002]. Patients undergoing treatment intensification resulting in decongestion had better outcome than patients with persistent (worsening) congestion despite LD dose up-titration (p < 0.001).

CONCLUSION

Intensification of pharmacological decongestion but not the actual LD dose was related to poor outcome in chronic HF. If treatment intensification translated into clinical decongestion, outcome was better than in case of persistent or worsening congestion.

Seeing the Invisible-Ultrasound Molecular Imaging

Ultrasound molecular imaging has been developed in the past two decades with the goal of non-invasively imaging disease phenotypes on a cellular level not depicted on anatomic imaging. Such techniques already play a role in pre-clinical research for the assessment of disease mechanisms and drug effects, and are thought to in the future contribute to earlier diagnosis of disease, assessment of therapeutic effects and patient-tailored therapy in the clinical field. In this review, we first describe the chemical composition and structure as well as the in vivo behavior of the ultrasound contrast agents that have been developed for molecular imaging. We then discuss the strategies that are used for targeting of contrast agents to specific cellular targets and protocols used for imaging. Next we describe pre-clinical data on imaging of thrombosis, atherosclerosis and microvascular inflammation and in oncology, including the pathophysiological principles underlying the selection of targets in each area. Where applicable, we also discuss efforts that are currently underway for translation of this technique into the clinical arena.

Prevalence and Management of Atrial Thrombi in Patients With Atrial Fibrillation Before Pulmonary Vein Isolation

OBJECTIVES

This study aimed to investigate the prevalence and management of left atrial (LA) thrombi detected by transesophageal echocardiography (TEE) in patients with atrial fibrillation undergoing pulmonary vein isolation (PVI).

BACKGROUND

Little data are available on LA thrombi before PVI.

METHODS

All patients scheduled for PVI between April 2010 and April 2018 undergoing pre-procedural TEE were analyzed. Management of LA thrombus was at the discretion of the treating physician.

RESULTS

In this study, 1,753 pre-procedural TEE from 1,358 patients (mean age 61 ± 10 years, 28% female) were included. Anticoagulation was used in 86% of all TEE (51% with direct oral anticoagulants [DOAC], 35% with vitamin K antagonists [VKA]). Thrombi were found in 11 TEE (0.6%), all in the LA appendage. Of the 11 patients with a thrombus, 5 (46%) had paroxysmal atrial fibrillation, 2 (18%) had a CHA₂DS₂-VASc (Congestive Heart Failure, Hypertension, Age ≥75 Years, Diabetes Mellitus, Prior Stroke or Transient Ischemic Attack or Thromboembolism, Vascular Disease, Age 65 to 74 Years, Sex) score of 1, and 5 (46%) were in sinus rhythm at the time of TEE. Of the 8 patients (72%) on anticoagulation therapy, 5 were treated with DOAC and 3 with VKA. Starting anticoagulation (n = 3), switching to VKA with a target international normalized ratio of 2.5 to 3 (n = 3), or switching to a DOAC (n = 1) or a different DOAC (n = 4) resulted in thrombus resolution in 9 of 11 patients (82%).

CONCLUSIONS

In patients with atrial fibrillation scheduled for PVI, LA thrombi are rare and present in <1%. Thrombi were found in patients on VKA and DOAC, in low-risk patients, and despite sinus rhythm. Thrombus resolution was achieved in the majority of patients by changing the anticoagulation regimen.

Non-invasive contrast enhanced ultrasound molecular imaging of inflammation in autoimmune myocarditis for prediction of left ventricular fibrosis and remodeling

Background

Myocarditis can lead to myocyte loss and myocardial fibrosis resulting in dilated cardiomyopathy (DCMP). Currently employed methods for assessing the risk for development of DCMP are inaccurate or rely on invasive myocardial biopsies. We hypothesized that molecular imaging of tissue inflammation with contrast enhanced ultrasound during peak inflammation in myocarditis could predict development of fibrosis and impaired left ventricular function.

Methods and results

Experimental autoimmune myocarditis (EAM) was induced in Balbc mice by injection of the α-myosin heavy chain peptide. Contrast enhanced ultrasound (CEU) using microbubbles targeted to leukocytes (MB_Lc), to CD4+ lymphocytes (MB_CD4), and to the endothelial cell adhesion molecule P-selectin (MB_PSel) was performed during the expected EAM peak inflammatory activity 21 days after induction. High resolution ultrasound, invasive hemodynamic measurements and fibrosis quantification were done 63 days after EAM assessment. All tested microbubbles correlated to fibrosis (MB_Lc spearman r 0.28, p 0.047, MB_CD4 r 0.44, p 0.01, MB_PSel r 0.73, p 0.02), however, correlations were weak overall and the spread of data was considerable. Also, targeted CEU data on day 21 did not correlate to hemodynamic and functional data on day 63.

Conclusions

Ultrasound molecular imaging using targeted microbubbles during the peak inflammatory activity of myocarditis correlates weakly with later development of fibrosis but not with hemodynamic or left ventricular functional parameters.

Ultrasound Molecular Imaging of Atherosclerosis With Nanobodies: Translatable Microbubble Targeting Murine and Human VCAM (Vascular Cell Adhesion Molecule) 1

OBJECTIVE

Contrast-enhanced ultrasound molecular imaging (CEUMI) of endothelial expression of VCAM (vascular cell adhesion molecule)-1 could improve risk stratification for atherosclerosis. The microbubble contrast agents developed for preclinical studies are not suitable for clinical translation. Our aim was to characterize and validate a microbubble contrast agent using a clinically translatable single-variable domain immunoglobulin (nanobody) ligand. Approach and Results: Microbubble with a nanobody targeting VCAM-1 (MB_cAbVcam1-5) and microbubble with a control nanobody (MB_VHH2E7) were prepared and characterized in vitro. Attachment efficiency to VCAM-1 under continuous and pulsatile flow was investigated using activated murine endothelial cells. In vivo CEUMI of the aorta was performed in atherosclerotic double knockout and wild-type mice after injection of MB_cAbVcam1-5 and MB_VHH2E7. Ex vivo CEUMI of human endarterectomy specimens was performed in a closed-loop circulation model. The surface density of the nanobody ligand was 3.5×10⁵ per microbubble. Compared with MB_VHH2E7, MB_cAbVcam1-5 showed increased attachment under continuous flow with increasing shear stress of 1-8 dynes/cm² while under pulsatile flow attachment occurred at higher shear stress. CEUMI in double knockout mice showed signal enhancement for MB_cAbVcam1-5 in early (P=0.0003 versus MB_VHH2E7) and late atherosclerosis (P=0.007 versus MB_VHH2E7); in wild-type mice, there were no differences between MB_cAbVcam1-5 and MB_VHH2E7. CEUMI in human endarterectomy specimens showed a 100% increase in signal for MB_cAbVcam1-5versus MB_VHH2E7 (20.6±27.7 versus 9.6±14.7, P=0.0156).

CONCLUSIONS

CEUMI of the expression of VCAM-1 is feasible in murine models of atherosclerosis and on human tissue using a clinically translatable microbubble bearing a VCAM-1 targeted nanobody.

Right ventricle and outcome in left ventricular non-compaction cardiomyopathy

BACKGROUND

The risk of adverse events in patients with left ventricular non-compaction cardiomyopathy (LVNC) is substantial. Information on prognostic factors, however, is limited. This study was designed to assess the prognostic value of right ventricular (RV) size and function in LVNC patients.

METHODS

Cox regression analyses were used to determine the association of indexed RV end-diastolic area (RV-EDAI), indexed end-diastolic diameter (RV-EDDI), fractional area change (FAC), and tricuspid annular systolic excursion (TAPSE) with the occurrence of death or heart transplantation (composite endpoint).

RESULTS

Out of 127 patients (53.2 ± 17.8 years; 61% males, median follow-up time was 7.7 years), 17 patients reached the endpoint. In a univariate analysis, RV-EDAI was the strongest predictor of outcome [HR 1.48 (1.24-1.77) per cm²/m²; p < 0.0001]. FAC was predictive as well [HR 1.44 (1.16-1.83) per 5% decrease; p = 0.0009], while TAPSE was not (p=ns). RV-EDAI remained an independent predictor in a bivariable analysis with indexed left ventricular ED volume [HR 1.41 (1.18-1.70) per cm²/m²; p = 0.0002], while analysis of FAC and left ventricular ejection fraction demonstrated that FAC was not independent [HR 1.20 (0.98-1.52); per 5% decrease; p = 0.0721]. RV-EDAI 11.5 cm²/m² was the best cut-off value for separating patients in terms of outcome. Patients with RV-EDAI >11.5 cm²/m² had a survival rate of 18.5% over 12 years as compared to 93.8% in patients with RV-EDAI <11.5 cm²/m² (p < 0.0001).

CONCLUSION

Increased end-diastolic RV size and decreased systolic RV function are predictors of adverse outcome in patients with LVNC. Patients with RV-EDAI >11.5 cm²/m² exhibit a significantly lower survival than those <11.5 cm²/m².

Prognostic Significance of Longitudinal Clinical Congestion Pattern in Chronic Heart Failure: Insights From TIME-CHF Trial

BACKGROUND

The relationship between longitudinal clinical congestion pattern and heart failure outcome is uncertain. This study was designed to assess the prevalence of congestion over time and to investigate its impact on outcome in chronic heart failure.

METHODS

A total of 588 patients with chronic heart failure older than 60 years of age with New York Heart Association (NYHA) functional class ≥II from the TIME-CHF study were included. The endpoints for this study were survival and hospitalization-free heart failure survival. Orthopnea, NYHA ≥III, paroxysmal nocturnal dyspnea, hepatomegaly, peripheral pitting edema, jugular venous distension, and rales were repeatedly investigated and related to outcomes. These congestion-related signs and symptoms were used to design a 7-item Clinical Congestion Index.

RESULTS

Sixty-one percent of patients had a Clinical Congestion Index ≥3 at baseline, which decreased to 18% at month 18. During the median [interquartile range] follow-up of 27.2 [14.3-39.8] months, 17%, 27%, and 47% of patients with baseline Clinical Congestion Index of 0, 1-2, and ≥3 at inclusion, respectively, died (P <.001). Clinical Congestion Index was identified as an independent predictor of mortality at all visits (P <.05) except month 6 and reduced hospitalization-free heart failure survival (P <.05). Successful decongestion was related to better outcome as compared to persistent congestion or partial decongestion (log-rank P <0.001).

CONCLUSIONS

The extent of congestion as assessed by means of clinical signs and symptoms decreased over time with intensified treatment, but it remained present or relapsed in a substantial number of patients with heart failure and was associated with poor outcome. This highlights the importance of appropriate decongestion in chronic heart failure.

Left atrial dimension and cardiovascular outcomes in patients with and without atrial fibrillation: a systematic review and meta-analysis

Objective

The prognostic value of left atrial (LA) dimensions may differ between patients with and without atrial fibrillation (AF).

Methods

MEDLINE and EMBASE were searched for studies that investigated the association between LA echocardiographic parameters measured by transthoracic echocardiography and cardiovascular outcomes in patients with or without AF. Data were independently abstracted by two reviewers and pooled using random-effects meta-analysis. The primary outcome was incident stroke or thromboembolic events. Secondary outcomes were heart failure, all-cause mortality and major adverse cardiac events (MACE).

Results

Twenty-three studies of patients with AF (14 939 patients) and 68 studies of patients without AF (50 720 patients) in this systematic review. Increasing LA diameter was significantly associated with stroke and thromboembolic events in patients without AF (risk ratio (RR) 1.38, 95% CI 1.02 to 1.87; p=0.03), but not in patients with AF (RR 1.02, 95% CI 0.98 to 1.07; p=0.27; p for difference=0.05). Increasing LA diameter index was significantly associated with MACE in patients with AF (RR 1.13, 95% CI 1.09 to 1.17; p<0.001) and in patients without AF (RR 2.98, 95% CI 1.90 to 4.66; p<0.001), with stronger effects in non-AF populations (p for difference <0.001). Greater LA volume index was significantly associated with the risk of MACE in patients with AF (RR 1.01, 95% CI 1.00 to 1.02; p=0.03) and in non-AF populations (RR 1.08, 95% CI 1.05 to 1.10; p<0.001), the association being stronger in individuals without AF (p for difference <0.001).

Conclusions

Larger LA parameters were associated with various adverse cardiovascular events. Many of these associations were stronger in individuals without AF, highlighting the potential importance of LA myopathy.

Targeting compensatory MEK/ERK activation increases JAK inhibitor efficacy in myeloproliferative neoplasms

Constitutive JAK2 signaling is central to myeloproliferative neoplasm (MPN) pathogenesis and results in activation of STAT, PI3K/AKT, and MEK/ERK signaling. However, the therapeutic efficacy of current JAK2 inhibitors is limited. We investigated the role of MEK/ERK signaling in MPN cell survival in the setting of JAK inhibition. Type I and II JAK2 inhibition suppressed MEK/ERK activation in MPN cell lines in vitro, but not in Jak2V617F and MPLW515L mouse models in vivo. JAK2 inhibition ex vivo inhibited MEK/ERK signaling, suggesting that cell-extrinsic factors maintain ERK activation in vivo. We identified PDGFRα as an activated kinase that remains activated upon JAK2 inhibition in vivo, and PDGF-AA/PDGF-BB production persisted in the setting of JAK inhibition. PDGF-BB maintained ERK activation in the presence of ruxolitinib, consistent with its function as a ligand-induced bypass for ERK activation. Combined JAK/MEK inhibition suppressed MEK/ERK activation in Jak2V617F and MPLW515L mice with increased efficacy and reversal of fibrosis to an extent not seen with JAK inhibitors. This demonstrates that compensatory ERK activation limits the efficacy of JAK2 inhibition and dual JAK/MEK inhibition provides an opportunity for improved therapeutic efficacy in MPNs and in other malignancies driven by aberrant JAK-STAT signaling.

Is the clinical presentation of chronic heart failure different in elderly versus younger patients and those with preserved versus reduced ejection fraction?

BACKGROUND

Whether the clinical presentation and in particular prevalence of symptoms and signs of heart failure (HF) is different in elderly versus younger patients and in those with reduced (HFrEF) versus preserved (HFpEF) left ventricular ejection fraction (LVEF) is a matter of ongoing debate.

AIMS

To compare detailed clinical characteristics of these important subgroups and to develop a prediction rule for the differentiation of HFpEF and HFrEF based on clinical parameters.

METHODS

The analysis was based on the Trial of Intensified versus standard Medical therapy in Elderly patients with Congestive Heart Failure (TIME-CHF) comprising 622 patients ≥60 years with HF including the whole LVEF spectrum.

RESULTS

In the groups ≥75 years and with HFpEF typical symptoms and clinical signs of HF were more prevalent as compared to those <75 years or with HFrEF, respectively. The burden of comorbidities was higher in the older age group. HFrEF could not be differentiated from HFpEF by symptom history and clinical examination alone. However, a combination of age, presence of pulmonary rales, systolic blood pressure, cause of heart failure, osteoporosis, current smoking, NT-proBNP, haemoglobin, QRS width and heart rhythm allowed to identify HFrEF versus HFpEF with a sensitivity of 81% and specificity of 90% (c-statistics 0.91).

CONCLUSIONS

More symptoms and signs of HF were present both in the older age group and in patients with HFpEF. HFpEF versus HFrEF could be differentiated by a set of simple clinical, laboratory and ECG parameters but not by symptom history and physical examination alone.

Fast-track versus long-term hospitalizations for patients with non-disabling acute ischaemic stroke

BACKGROUND AND PURPOSE

The aim was to assess the feasibility and safety of fast-track hospitalizations in a selected cohort of patients with stroke.

METHODS

Patients hospitalized at the Stroke Center of the University Hospital Basel, Switzerland, with an acute ischaemic stroke confirmed on magnetic resonance diffusion-weighted imaging were included. Neurological deficits of the included patients were non-disabling, i.e. not interfering with activities of daily living and compatible with a direct discharge home. Patients with premorbid disability were excluded. All patients were admitted to the Stroke Center for ≥24 h. Two study groups were compared - fast-track hospitalizations (≤72 h) and long-term hospitalizations (>72 h). The primary end-point was a composite of any unplanned rehospitalization for any reason within 3 months since hospital discharge and a modified Rankin Scale 3-6 at 3 months. Adjustment for confounders was done using the inverse probability of treatment weights (IPTW).

RESULTS

Amongst the 521 patients who met the inclusion criteria, fast-track hospitalizations were performed in 79 patients (15%). In the fast-track group, seven patients (8.9%) met the primary end-point, compared to 37 (8.4%) in the long-term group [odds ratio (OR) 1.06, 95% confidence interval (CI) 0.42-2.34, P = 0.88]. After weighting for IPTW, the odds of the primary end-point remained similar between the two arms (OR_IPTW 1.27, 95% CI 0.51-3.16, P = 0.61). The costs of fast-track hospitalizations were lower, on average, by $4994.

CONCLUSIONS

Fast-track hospitalizations including a full workup proved to be feasible, showed no increased risk and were less expensive than long-term hospitalizations.

Scaffold Composition Determines the Angiogenic Outcome of Cell-Based Vascular Endothelial Growth Factor Expression by Modulating Its Microenvironmental Distribution

Delivery of genetically modified cells overexpressing Vascular Endothelial Growth Factor (VEGF) is a promising approach to induce therapeutic angiogenesis in ischemic tissues. The effect of the protein is strictly modulated by its interaction with the components of the extracellular matrix. Its therapeutic potential depends on a sustained but controlled release at the microenvironmental level in order to avoid the formation of abnormal blood vessels. In this study, it is hypothesized that the composition of the scaffold plays a key role in modulating the binding, hence the therapeutic effect, of the VEGF released by 3D-cell constructs. It is found that collagen sponges, which poorly bind VEGF, prevent the formation of localized hot spots of excessive concentration, therefore, precluding the development of aberrant angiogenesis despite uncontrolled expression by a genetically engineered population of adipose tissue-derived stromal cells. On the contrary, after seeding on VEGF-binding egg-white scaffolds, the same cell population caused aberrantly enlarged vascular structures after 14 d. Collagen-based engineered tissues also induced a safe and efficient angiogenesis in both the patch itself and the underlying myocardium in rat models. These findings open new perspectives on the control and the delivery of proangiogenic stimuli, and are fundamental for the vascularization of engineered tissues/organs.

Comparison of Benefit of Successful Percutaneous Coronary Intervention for Chronic Total Occlusion in Patients With Versus Without Reduced (≤40%) Left Ventricular Ejection Fraction

Successful recanalization of chronic total occlusions (CTO) has been associated with improved survival. Data on outcomes in patients with left ventricular (LV) systolic dysfunction undergoing percutaneous coronary intervention for CTO, however, are scarce. Between January 2005 and December 2013, a total of 2,002 consecutive patients undergoing elective CTO percutaneous coronary intervention at a tertiary care center were divided into patients with (LV ejection fraction ≤ 40%) and without (LV ejection fraction > 40%) LV systolic dysfunction as defined by transthoracic echocardiography. The primary end point was all-cause mortality. Median follow-up was 2.6 (1.1 to 3.1) years. A total of 348 (17.4%) patients had LV dysfunction. All-cause mortality was higher in patients with LV dysfunction (30.2%) than in those with normal LV function (8.2%, p <0.001), and associations remained significant after adjustment for baseline differences (adjusted hazard ratio [HR] 3.39, 95% confidence interval [CI] 2.57 to 4.47, p <0.001). Successful CTO recanalization was independently associated with reduced all-cause mortality, with similar relative risk reductions in both the preserved (6.6% vs 16.9%, adjusted HR 0.48, 95% CI 0.34 to 0.70, p <0.001) and the reduced LV function groups (26.2% vs 45.2%, adjusted HR 0.63, 95% CI 0.41 to 0.98, p = 0.04, interaction p = 0.28). In conclusion, irrespective of LV function, successful CTO recanalization is associated with a clear survival benefit.

Dual targeting improves capture of ultrasound microbubbles towards activated platelets but yields no additional benefit for imaging of arterial thrombosis

Platelets can be found on the surface of inflamed and ruptured atherosclerotic plaques. Thus, targeting of activated platelets may allow for molecular imaging of vulnerable atherosclerotic lesions. We here investigated microbubbles (MB) functionalized with the selectin ligand sialyl Lewis^a individually (MB_sLea) or dually with sLe^a and an antibody targeting ligand-induced binding sites of the activated GPIIb/IIIa receptor (MB_Dual). Assessed by in vitro flow chamber, targeted MB exhibited increased adhesion to platelets as compared to MB_Control. While MB_sLea rolled slowly on the platelets’ surface, MB_Dual enhanced the percentage of firm adhesion. In vivo, MB were investigated by ultrasound in a model of ferric chloride induced non-occlusive carotid artery thrombosis. MB_sLea and MB_Dual revealed a higher ultrasound mean acoustic intensity than MB_Control (p < 0.05), however MB_Dual demonstrated no additional increase in mean signal intensity as compared to MB_sLea. The degree of carotid artery stenosis on histology correlated well with the ultrasound acoustic intensity of targeted MB (p < 0.05). While dual targeting of MB using fast binding carbohydrate polymers and specific antibodies is a promising strategy to support adhesion to activated platelets under arterial shear stress, these advantages seem not readily translatable to in vivo models.

Diversity in livestock resources in pastoral systems in Africa

Pastoral systems are important producers and repositories of livestock diversity. Pastoralists use variability in their livestock resources to manage high levels of environmental variability in economically advantageous ways. In pastoral systems, human-animal-environment interactions are the basis of production and the key to higher productivity and efficiency. In other words, pastoralists manage a production system that exploits variability and keeps production costs low. When differentiating, characterising and evaluating pastoral breeds, this context-specific, functional dimension of diversity in livestock resources needs to be considered. The interaction of animals with their environment is determined not only by morphological and physiological traits but also by experience and socially learned behaviour. This high proportion of non-genetic components determining the performance of livestock means that current models for analysing livestock diversity and performance, which are based on genetic inheritance, have limited ability to describe pastoral performance. There is a need for methodological innovations to evaluate pastoral breeds and animals, since comparisons based on performance 'under optimal conditions' are irrelevant within this production system. Such innovations must acknowledge that livestock or breed performance is governed by complex human-animal-environment interactions, and varies through time and space due to the mobile and seasonal nature of the pastoral system. Pastoralists' breeding concepts and selection strategies seem to be geared towards improving their animals' capability to exploit variability, by - among other things - enhancing within-breed diversity. In-depth studies of these concepts and strategies could contribute considerably towards developing methodological innovations for the characterisation and evaluation of pastoral livestock resources.

Conventional versus 3-D Echocardiography to Predict Arrhythmia Recurrence After Atrial Fibrillation Ablation

BACKGROUND

Arrhythmia recurrence after atrial fibrillation (AF) ablation remains high and requires repeat interventions in a substantial number of patients. We assessed the value of conventional and 3-D echocardiography to predict AF recurrence.

METHODS AND RESULTS

Consecutive patients undergoing AF ablation by means of pulmonary vein isolation were included in a prospective registry. Echocardiograms were obtained prior to the ablation procedure, and analyzed offline in a standardized manner, including 3-D left atrial (LA) volumetry and determination of LA function and sphericity. The primary endpoint, AF recurrence (>30 seconds) between 3 to 12 months after AF ablation, was independently adjudicated. We included 276 patients (73% male, mean age 59.9 ± 9.9 years). Paroxysmal and persistent AF were present in 178 (64%) and 98 (36%) patients, respectively. Mean left ventricular ejection fraction and indexed LA volume in 3-D (LAVI) were 52 ± 12% and 42 ± 13 mL/m² , respectively. AF recurrence was observed in 110 (40%) patients after a single procedure. Median (interquartile range) time to AF recurrence was 123 (92; 236) days. In multivariable Cox regression models, the only predictors for AF recurrence were the minimal, maximal, and indexed 3-D LA volumes, P = 0.024, P = 0.016, and P = 0.014, respectively. Quartile specific analysis of 3-D LAVI showed an HR of 1.885 (95%CI 1.066-3.334; P for trend = 0.015) for the highest compared to the lowest quartile.

CONCLUSION

Our results show the important role of LA volume for the long-term freedom from arrhythmia after AF ablation. These data also highlight the potential of 3-D echocardiography in this context and may facilitate patient selection for AF ablation.

Heart failure with mid-range ejection fraction: a distinct clinical entity? Insights from the Trial of Intensified versus standard Medical therapy in Elderly patients with Congestive Heart Failure (TIME-CHF)

AIMS

While the conditions of heart failure (HF) with reduced (HFrEF, LVEF < 40%) and preserved (HFpEF, LVEF ≥ 50%) left ventricular ejection fraction (LVEF) are well characterized, it is unknown whether patients with HF and mid-range LVEF (HFmrEF, LVEF 40-49%) have to be regarded as a separate clinical entity. The aim of this study was to characterize these three populations and to compare outcome and response to therapy.

METHODS AND RESULTS

The analysis was based on the Trial of Intensified versus standard Medical therapy in Elderly patients with Congestive Heart Failure (TIME-CHF) comprising a population with established HF including the whole spectrum of LVEF. Of the 622 patients, 108 (17%) were classified as having HFmrEF. This group was in general found to be 'intermediate' regarding clinical characteristics with a comparable and high burden of comorbidities and equally impaired quality of life but was more likely to have coronary artery disease as compared with the HFpEF group. During a median follow-up of 794 days, mortality was 39.7% without significant differences between groups. N-terminal pro-B-type natriuretic peptide (NT-proBNP)-guided as compared with standard therapy resulted in improved survival free of HF hospitalizations in HFrEF and HFmrEF, but not in HFpEF.

CONCLUSION

Although the 'intermediate' clinical profile of HFmrEF between HFrEF and HFpEF would support the conclusion that HFmrEF is a distinct clinical entity, we hypothesize that HFmrEF has to be categorized as HFrEF because of the high prevalence of coronary artery disease and the similar benefit of NT-proBNP-guided therapy in HFrEF and HFmrEF, in contrast to HFpEF.

Determinants of Left Atrial Volume in Patients with Atrial Fibrillation

Introduction

Left atrial (LA) enlargement is an important risk factor for incident stroke and a key determinant for the success of rhythm control strategies in patients with atrial fibrillation (AF). However, factors associated with LA volume in AF patients remain poorly understood.

Methods

Patients with paroxysmal or persistent AF were enrolled in this study. Real time 3-D echocardiography was performed in all participants and analyzed offline in a standardized manner. We performed stepwise backward linear regression analyses using a broad set of clinical parameters to determine independent correlates for 3-D LA volume.

Results

We included 210 patients (70.9% male, mean age 61±11years). Paroxysmal and persistent AF were present in 95 (45%) and 115 (55%) patients, respectively. Overall, 115 (55%) had hypertension, 11 (5%) had diabetes, and 18 (9%) had ischemic heart disease. Mean indexed LA volume was 36±12ml/m². In multivariable models, significant associations were found for female sex (β coefficient -10.51 (95% confidence interval (CI) -17.85;-3.16), p = 0.0053), undergoing cardioversion (β 11.95 (CI 5.15; 18.74), p = 0.0006), diabetes (β 14.23 (CI 2.36; 26.10), p = 0.019), body surface area (BSA) (β 34.21 (CI 19.30; 49.12), p<0.0001), glomerular filtration rate (β -0.21 (CI -0.36; -0.06), p = 0.0064) and plasma levels of NT-pro brain natriuretic peptide (NT-proBNP) (β 6.79 (CI 4.05; 9.52), p<0.0001), but not age (p = 0.59) or hypertension (p = 0.42). Our final model explained 52% of the LA volume variability.

Conclusions

In patients with AF, the most important correlates with LA volume are sex, BSA, diabetes, renal function and NT-proBNP, but not age or hypertension. These results may help to refine rhythm control strategies in AF patients.

Von Willebrand Factor Interacts with Surface-Bound C1q and Induces Platelet Rolling

Premature atherosclerosis and thrombotic complications are major causes of morbidity and mortality in patients with systemic lupus erythematosus (SLE). However, the high incidence of these complications cannot be explained by traditional risk factors alone, suggesting direct effects of an activated immune system on hemostasis. The unexpected nucleotide sequence homology between SLE patient-derived autoantibodies against complement C1q (Fab anti-C1q) and von Willebrand factor (VWF) led us to investigate a potential interaction between the complement and hemostatic systems on the level of initiating molecules. VWF was found to bind to surface-bound C1q under static conditions. The binding could specifically be inhibited by Fab anti-C1q and C1q-derived peptides. Under shear stress the C1q-VWF interaction was enhanced, resembling the binding of VWF to collagen I. Additionally, we could show that C1q-VWF complexes induced platelet rolling and firm adhesion. Furthermore, we observed VWF binding to C1q-positive apoptotic microparticles and cholesterol crystals, as well as increased VWF deposition in C1q-positive glomeruli of SLE patients compared with control nephropathy. We show, to our knowledge for the first time, binding of VWF to C1q and thus a direct interaction between starter molecules of hemostasis and the classical pathway of complement. This direct interaction might contribute to the pathogenic mechanisms in complement-mediated, inflammatory diseases.

Noninvasive Contrast-Enhanced Ultrasound Molecular Imaging Detects Myocardial Inflammatory Response in Autoimmune Myocarditis

Background—

Cardiac tests for diagnosing myocarditis lack sensitivity or specificity. We hypothesized that contrast-enhanced ultrasound molecular imaging could detect myocardial inflammation and the recruitment of specific cellular subsets of the inflammatory response in murine myocarditis.

Methods and Results—

Microbubbles (MB) bearing antibodies targeting lymphocyte CD4 (MB CD4 ), endothelial P-selectin (MB PSel ), or isotype control antibody (MB Iso ) and MB with a negative electric charge for targeting of leukocytes (MB Lc ) were prepared. Attachment of MB CD4 was validated in vitro using murine spleen CD4+ T cells. Twenty-eight mice were studied after the induction of autoimmune myocarditis by immunization with α-myosin-peptide; 20 mice served as controls. Contrast-enhanced ultrasound molecular imaging of the heart was performed. Left ventricular function was assessed by conventional and deformation echocardiography, and myocarditis severity graded on histology. Animals were grouped into no myocarditis, moderate myocarditis, and severe myocarditis. In vitro, attachment of MB CD4 to CD4+ T cells was significantly greater than of MB Iso . Of the left ventricular ejection fraction or strain and strain rate readouts, only longitudinal strain was significantly different from control animals in severe myocarditis. In contrast, contrast-enhanced ultrasound molecular imaging showed increased signals for all targeted MB versus MB Iso both in moderate and severe myocarditis, and MB CD4 signal correlated with CD4+ T-lymphocyte infiltration in the myocardium.

Conclusions—

Contrast-enhanced ultrasound molecular imaging can detect endothelial inflammation and leukocyte infiltration in myocarditis in the absence of a detectable decline in left ventricular performance by functional imaging. In particular, imaging of CD4+ T cells involved in autoimmune responses could be helpful in diagnosing myocarditis.

Whole Blood Gene Expression Differentiates between Atrial Fibrillation and Sinus Rhythm after Cardioversion

Background

Treatment to restore sinus rhythm among patients with atrial fibrillation (AF) has limited long-term success rates. Gene expression profiling may provide new insights into AF pathophysiology.

Objective

To identify biomarkers and improve our understanding of AF pathophysiology by comparing whole blood gene expression before and after electrical cardioversion (ECV).

Methods

In 46 patients with persistent AF that underwent ECV, whole blood samples were collected 1–2 hours before and 4 to 6 weeks after successful cardioversion. The paired samples were sent for microarray and plasma biomarker comparison.

Results

Of 13,942 genes tested, expression of SLC25A20 and PDK4 had the strongest associations with AF. Post-cardioversion, SLC25A20 and PDK4 expression decreased by 0.8 (CI 0.7–0.8, p = 2.0x10^-6) and 0.7 (CI 0.6–0.8, p = 3.0x10^-5) fold respectively. Median N-terminal pro B-type natriuretic peptide (NT-proBNP) concentrations decreased from 127.7 pg/mL to 44.9 pg/mL (p = 2.3x10^-13) after cardioversion. AF discrimination models combining NT-proBNP and gene expression (NT-proBNP + SLC25A20 area under the curve = 0.88, NT-proBNP + PDK4 AUC = 0.86) had greater discriminative capacity as compared with NT-proBNP alone (AUC = 0.82). Moreover, a model including NT-proBNP, SLC25A20 and PDK4 significantly improved AF discrimination as compared with other models (AUC = 0.87, Net Reclassification Index >0.56, p<5.8x10^-3). We validated the association between SLC25A20 and PDK4 with AF in an independent sample of 17 patients.

Conclusion

This study demonstrates that SLC25A20, PDK4, and NT-proBNP have incremental utility as biomarkers discriminating AF from sinus rhythm. Elevated SLC25A20 and PDK4 expression during AF indicates an important role for energy metabolism in AF.

Isolated double-orifice mitral valve: a case report

Background

Double-orifice mitral valve is an extremely rare cardiac anomaly possibly originating from insufficient endocardial fusion in embryogenesis. Severe concomitant cardiac anomalies and malfunction of the valve usually lead to an early diagnosis in childhood. Therefore the prevalence of isolated double-orifice mitral valve in adulthood is not known.

Case presentation

We present the case of a 63 years old, female Caucasian patient with isolated double-orifice mitral valve diagnosed in routine echocardiographic evaluation after chemotherapy presenting without clinical symptoms.

Conclusion

Trans-thoracic echocardiography is a suitable modality to diagnose and further assess anatomical and functional properties of the anomaly. In the presence of double-orifice mitral valve concomitant cardiac anomalies and valvular stenosis or regurgitation must be excluded. If an isolated double-orifice mitral valve with no functional abnormalities is present, no further follow-up is necessary.

Electronic supplementary material

The online version of this article (doi:10.1186/s12872-015-0168-0) contains supplementary material, which is available to authorized users.

Ultrasound imaging for risk assessment in atherosclerosis

Atherosclerosis and its consequences like acute myocardial infarction or stroke are highly prevalent in western countries, and the incidence of atherosclerosis is rapidly rising in developing countries. Atherosclerosis is a disease that progresses silently over several decades before it results in the aforementioned clinical consequences. Therefore, there is a clinical need for imaging methods to detect the early stages of atherosclerosis and to better risk stratify patients. In this review, we will discuss how ultrasound imaging can contribute to the detection and risk stratification of atherosclerosis by (a) detecting advanced and early plaques; (b) evaluating the biomechanical consequences of atherosclerosis in the vessel wall;

Non-invasive nuclear myocardial perfusion imaging improves the diagnostic yield of invasive coronary angiography

AIMS

Several studies reported on the moderate diagnostic yield of elective invasive coronary angiography (ICA) regarding the presence of coronary artery disease (CAD), but limited data are available on how prior testing for ischaemia may contribute to improve the diagnostic yield in an every-day clinical setting. This study aimed to assess the value and use of cardiac myocardial perfusion single photon emission computed tomography (MPS) in patient selection prior to elective ICA.

METHODS AND RESULTS

The rate of MPS within 90 days prior to elective ICA was assessed and the non-invasive test results were correlated with the presence of obstructive CAD on ICA (defined as stenosis of ≥50% of a major epicardial coronary vessel). Multivariate logistic regression analysis was performed to identify predictors of obstructive CAD. A total of 7530 consecutive patients were included. At catheterization, 3819 (50.7%) were diagnosed as having obstructive CAD. Patients with a positive result on MPS (performed in 23.5% of patients) were significantly more likely to have obstructive CAD as assessed by ICA than those who did not undergo non-invasive testing (74.4 vs. 45.6%, P < 0.001). Furthermore, a pathological MPS result was a strong, independent predictor for CAD findings among traditional risk factors and symptoms.

CONCLUSION

In an every-day clinical setting, the use of MPS substantially increases the diagnostic yield of elective ICA and provides incremental value over clinical risk factors and symptoms in predicting obstructive CAD, thus emphasizing its importance in the decision-making process leading to the use of diagnostic catheterization.

Effects of sinus rhythm maintenance on left heart function after electrical cardioversion of atrial fibrillation: implications for tachycardia-induced cardiomyopathy

BACKGROUND

The role of tachycardia-induced cardiomyopathy vs tachycardia-related short diastolic filling period and reduced atrial contraction in decline of left ventricular ejection fraction (LVEF) in atrial fibrillation (AF) is uncertain. We aimed to characterize left heart changes over time in patients with AF who undergo electrical cardioversion (ECV).

METHODS

Consecutive AF patients who were to undergo ECV were enrolled. Patients with unstable or acute heart failure, severe valvular diseases, recent open-heart surgery, major disorders, or an unsuccessful ECV were excluded. Transthoracic echocardiography, including 3-dimensional left atrial and ventricular volume acquisitions, was performed 1-2 hours before and after ECV, and 4-6 weeks later.

RESULTS

In 73 patients (77% male, 66 ± 11 years), ECV resulted in an immediate increase in LVEF (from 43 [interquartile range (IQR), 33-50%] to 48 [IQR, 40-53%]; P < 0.0001). Four to 6 weeks after ECV, ejection fraction increased further in patients who remained in sinus rhythm (SR) (n = 55) to 55 (IQR, 44-62)%; P < 0.001. In patients with AF relapse, LVEF returned to values comparable to pre-ECV (n = 18) (44 [IQR, 32-51]%; P = 0.03). The atrial emptying fraction did not significantly change immediately after ECV (n = 69; from 20 [IQR, 13-25]% to 20 [IQR, 15-28]%; P = 0.14). Only patients who remained in SR showed an increase in atrial emptying fraction after 4-6 weeks (n = 51; to 37 [IQR, 26-48]%; P < 0.0001 vs post-ECV).

CONCLUSIONS

Immediate improvement in LVEF after ECV explains approximately 50% of total LVEF increase over time. However, in SR, LVEF, and atrial function continuously increase over 4-6 weeks after ECV. This might be attributable to recovery of tachycardia-induced cardiomyopathy.

Propionibacterium acnes prosthetic valve endocarditis with abscess formation: a case report

BACKGROUND

Endocarditis due to Propionibacterium acnes is a rare disease. Scant data on treatment of these infections is available and is based on case reports only. If the disease is complicated by abscess formation, surgical intervention combined with an antibiotic therapy might improve clinical outcome. In some cases, cardiac surgeons are reluctant to perform surgery, since they consider the intervention as high risk. Therefore, a conservative therapy is required, with little, if any evidence to choose the optimal antibiotic. We report the first case of a successfully treated patient with P. acnes prosthetic valve endocarditis without surgery.

CASE PRESENTATION

We report the case of a 29-year-old patient with a prosthetic valve endocarditis and composite graft infection with abscess formation of the left ventricular outflow tract due to P. acnes. Since cardiac surgery was considered as high risk, the patient was treated intravenously with ceftriaxone 2 g qd and rifampin 600 mg bid for 7 weeks and was switched to an oral therapy with levofloxacin 500 mg bid and rifampin 600 mg bid for an additional 6 months. Two sets of blood cultures collected six weeks after completion of treatment remained negative. The patient is considered to be cured based on absence of clinical signs and symptoms, normal laboratory parameters, negative radiology scans and negative blood cultures, determined at site visits over two years after completion of treatment.

CONCLUSION

To our knowledge, this is the first successfully managed patient with P. acnes prosthetic valve endocarditis with abscess formation of the left ventricular outflow tract who was treated with antibiotics alone without a surgical intervention. A six month treatment with a rifampin and levofloxacin combination was chosen, based on the excellent activity against stationary-phase and adherent bacteria.

Interaction between pulmonary hypertension and diastolic dysfunction in an elderly heart failure population

BACKGROUND

Pulmonary hypertension due to left heart disease is very common. Our aim was to investigate the relationship of the severity of left ventricular diastolic dysfunction with precapillary and postcapillary pulmonary hypertension (PH) in an elderly heart failure (HF) population.

METHODS AND RESULTS

A post hoc analysis of the Trial of Intensified Medical Therapy in Elderly Patients With Congestive Heart Failure data was done. Baseline transthoracic echocardiography was used to categorize diastolic function, estimate pulmonary artery pressure and pulmonary capillary wedge pressure, and calculate the transpulmonary pressure gradient (TPG). Among 392 HF patients, PH was present in 31% of patients with grade 1, in 37% of patients with grade 2, and in 65% of patients with grade 3 diastolic dysfunction; 54% of all HF patients with PH had a TPG >12 mm Hg, suggesting not only a postcapillary but also an additional precapillary component of PH. Survival was not related to the severity of diastolic dysfunction, but was worse in patients with PH (hazard ratio 1.63, 95% confidence interval 1.07-2.51; P = .024).

CONCLUSIONS

Our data indicate that HF patients with even mild diastolic dysfunction often have PH. Echocardiographic assessment suggest that the presence of PH might not simply be due to increased PCWP, but in part due to a precapillary component.

[Valvular heart disease: preoperative assessment and postoperative care]

Patients with valvular heart disease or with a prosthetic heart valve replacement are seen with increasing frequency in clinical practice. The medical care and evaluation of patients with valvular heart disease before valve surgery, but also the post-operative treatment is complex and managed by general practitioners, cardiologists and cardiac surgeons. In this mini-review we will first discuss the preoperative assessment of the two most common valvulopathies, aortic stenosis and mitral regurgitation. Then we will discuss the post-operative care, which includes the management of anticoagulation, serial follow up and as well as the diagnostic assessment of complications such as thromboembolism, hemolysis, endocarditis and valve dysfunction.

Molecular imaging reveals rapid reduction of endothelial activation in early atherosclerosis with apocynin independent of antioxidative properties

OBJECTIVE

Antioxidative drugs continue to be developed for the treatment of atherosclerosis. Apocynin is an nicotinamide adenine dinucleotide phosphate oxidase inhibitor with anti-inflammatory properties. We used contrast-enhanced ultrasound molecular imaging to assess whether short-term apocynin therapy in atherosclerosis reduces vascular oxidative stress and endothelial activation

APPROACH AND RESULTS

Genetically modified mice with early atherosclerosis were studied at baseline and after 7 days of therapy with apocynin (4 mg/kg per day IP) or saline. Contrast-enhanced ultrasound molecular imaging of the aorta was performed with microbubbles targeted to vascular cell adhesion molecule 1 (VCAM-1; MB(V)), to platelet glycoprotein Ibα (MB(Pl)), and control microbubbles (MB(Ctr)). Aortic vascular cell adhesion molecule 1 was measured using Western blot. Aortic reactive oxygen species generation was measured using a lucigenin assay. Hydroethidine oxidation was used to assess aortic superoxide generation. Baseline signal for MBV (1.3 ± 0.3 AU) and MB(Pl )(1.5 ± 0.5 AU) was higher than for MBCtr (0.5 ± 0.2 AU; P<0.01). In saline-treated animals, signal did not significantly change for any microbubble agent, whereas short-term apocynin significantly (P<0.05) reduced vascular cell adhesion molecule 1 and platelet signal (MBV: 0.3 ± 0.1; MBPl: 0.4 ± 0.1; MBCtr: 0.3 ± 0.2 AU; P=0.6 between agents). Apocynin reduced aortic vascular cell adhesion molecule 1 expression by 50% (P<0.05). However, apocynin therapy did not reduce reactive oxygen species content, superoxide generation, or macrophage content.

CONCLUSIONS

Short-term treatment with apocynin in atherosclerosis reduces endothelial cell adhesion molecule expression. This change in endothelial phenotype can be detected by molecular imaging before any measurable decrease in macrophage content and is not associated with a detectable change in oxidative burden.

Noninvasive ultrasound molecular imaging of the effect of statins on endothelial inflammatory phenotype in early atherosclerosis

BACKGROUND/OBJECTIVES

Inflammatory changes on the endothelium are responsible for leukocyte recruitment to plaques in atherosclerosis. Noninvasive assessment of treatment-effects on endothelial inflammation may be of use for managing medical therapy and developing novel therapies. We hypothesized that molecular imaging of vascular cell adhesion molecule-1 (VCAM-1) with contrast enhanced ultrasound (CEU) could assess treatment effects on endothelial phenotype in early atherosclerosis.

METHODS

Mice with atherosclerosis produced by gene deletion of the LDL-receptor and Apobec-1-editing protein were studied. At 12 weeks of age, mice received 8 weeks of regular chow or atorvastatin-enriched chow (10 mg/kg/day). At 20 weeks, CEU molecular imaging for aortic endothelial VCAM-1 expression was performed with VCAM-1-targeted (MB(VCAM)) and control microbubbles (MB(Ctr)). Aortic wall thickness was assessed with high frequency ultrasound. Histology, immunohistology and Western blot were used to assess plaque burden and VCAM-1 expression.

RESULTS

Plaque burden was reduced on histology, and VCAM-1 was reduced on Western blot by atorvastatin, which corresponded to less endothelial expression of VCAM-1 on immunohistology. High frequency ultrasound did not detect differences in aortic wall thickness between groups. In contrast, CEU molecular imaging demonstrated selective signal enhancement for MB(VCAM) in non-treated animals (MB(VCAM) 2±0.3 vs MB(Ctr) 0.7±0.2, p<0.01), but not in statin-treated animals (MB(VCAM) 0.8±0.2 vs MB(Ctr) 1.0±0.2, p = ns; p<0.01 for the effect of statin on MB(VCAM) signal).

CONCLUSIONS

Non-invasive CEU molecular imaging detects the effects of anti-inflammatory treatment on endothelial inflammation in early atherosclerosis. This easily accessible, low-cost technique may be useful in assessing treatment effects in preclinical research and in patients.

Predictors for efficacy of percutaneous mitral valve repair using the MitraClip system: the results of the MitraSwiss registry

BACKGROUND

Percutaneous mitral valve repair (MVR) using the MitraClip system has become a valid alternative for patients with severe mitral regurgitation (MR) and high operative risk.

OBJECTIVE

To identify clinical and periprocedural factors that may have an impact on clinical outcome.

DESIGN

Multi-centre longitudinal cohort study.

SETTING

Tertiary referral centres.

PATIENTS

Here we report on the first 100 consecutive patients treated with percutaneous MVR in Switzerland between March 2009 and April 2011. All of them had moderate-severe (3+) or severe (4+) MR, and 62% had functional MR. 82% of the patients were in New York Heart Association (NYHA) class III/IV, mean left ventricular ejection fraction was 48% and the median European System for Cardiac Operative Risk Evaluation was 16.9%.

INTERVENTIONS

MitraClip implantation performed under echocardiographic and fluoroscopic guidance in general anaesthesia.

MAIN OUTCOME MEASURES

Clinical, echocardiographic and procedural data were prospectively collected.

RESULTS

Acute procedural success (APS, defined as successful clip implantation with residual MR grade ≤2+) was achieved in 85% of patients. Overall survival at 6 and 12 months was 89.9% (95% CI 81.8 to 94.6) and 84.6% (95% CI 74.7 to 91.0), respectively. Univariate Cox regression analysis identified APS (p=0.0069) and discharge MR grade (p=0.03) as significant predictors of survival.

CONCLUSIONS

In our consecutive cohort of patients, APS was achieved in 85%. APS and residual discharge MR grade are important predictors of mid-term survival after percutaneous MVR.

Molecular imaging of inflammation and platelet adhesion in advanced atherosclerosis effects of antioxidant therapy with NADPH oxidase inhibition

BACKGROUND

In atherosclerosis, local generation of reactive oxygen species amplifies the inflammatory response and contributes to plaque vulnerability. We used molecular imaging to test whether inhibition of NADPH oxidase with apocynin would reduce endothelial inflammatory activation and endothelial-platelet interactions, thereby interrupting progression to high-risk plaque phenotype.

METHODS AND RESULTS

Mice deficient for both the low-density lipoprotein receptor and Apobec-1 were studied at 30 weeks of age and again after 10 weeks with or without apocynin treatment (10 or 50 mg/kg per day orally). In vivo molecular imaging of vascular cell adhesion molecule-1 (VCAM 1) P-selectin, and platelet glycoprotein-1bα (GPIbα) in the thoracic aorta was performed with targeted contrast-enhanced ultrasound molecular imaging. Arterial elastic modulus and pulse wave transit time were assessed using ultrahigh frequency ultrasound and invasive hemodynamic measurements. Plaque size and composition were assessed by histology. Molecular imaging in nontreated mice detected a 2-fold increase in P-selectin expression, VCAM-1 expression, and platelet adhesion between 30 and 40 weeks of age. Apocynin reduced all of these endothelial events in a dose-dependent fashion (25% and 50% reduction in signal at 40 weeks for low- and high-dose apocynin). Apocynin also decreased aortic elastic modulus and increased the pulse transit time. On histology, apocynin reduced total monocyte accumulation in a dose-dependent manner as well as platelet adhesion, although total plaque area was reduced in only the high-dose apocynin treatment group.

CONCLUSIONS

Inhibition of NADPH oxidase in advanced atherosclerosis reduces endothelial activation and platelet adhesion, which are likely responsible for the arrest of plaque growth and improvement of vascular mechanical properties.