Daniel Augustine

Dynamic Release and Clearance of Circulating Microparticles During Cardiac Stress

Rationale: Microparticles are cell-derived membrane vesicles, relevant to a range of biological responses and known to be elevated in cardiovascular disease. Objective: To investigate microparticle release during cardiac stress and how this response differs in those with vascular disease. Methods and Results: We measured a comprehensive panel of circulating cell-derived microparticles by a standardized flow cytometric protocol in 119 patients referred for stress echocardiography. Procoagulant, platelet, erythrocyte, and endothelial but not leukocyte, granulocyte, or monocyte-derived microparticles were elevated immediately after a standardized dobutamine stress echocardiogram and decreased after 1 hour. Twenty-five patients developed stress-induced wall motion abnormalities suggestive of myocardial ischemia. They had similar baseline microparticle levels to those who did not develop ischemia, but, interestingly, their microparticle levels did not change during stress. Furthermore, no stress-induced increase was observed in those without inducible ischemia but with a history of vascular disease. Fourteen patients subsequently underwent coronary angiography. A microparticle rise during stress echocardiography had occurred only in those with normal coronary arteries. Conclusions: Procoagulant, platelet, erythrocyte, and endothelial microparticles are released during cardiac stress and then clear from the circulation during the next hour. This stress-induced rise seems to be a normal physiological response that is diminished in those with vascular disease.

The Preterm Heart in Adult Life: Cardiovascular Magnetic Resonance Reveals Distinct Differences in Left Ventricular Mass, Geometry and Function

Background— Preterm birth leads to an early switch from fetal to postnatal circulation before completion of left ventricular in utero development. In animal studies, this results in an adversely remodeled left ventricle. We determined whether preterm birth is associated with a distinct left ventricular structure and function in humans. Methods and Results— A total of 234 individuals 20 to 39 years of age underwent cardiovascular magnetic resonance. One hundred two had been followed prospectively since preterm birth (gestational age=30.3±2.5 week; birth weight=1.3±0.3 kg), and 132 were born at term to uncomplicated pregnancies. Longitudinal and short-axis cine images were used to quantify left ventricular mass, 3-dimensional geometric variation by creation of a unique computational cardiac atlas, and myocardial function. We then determined whether perinatal factors modify these left ventricular parameters. Individuals born preterm had increased left ventricular mass (66.5±10.9 versus 55.4±11.4 g/m2; P<0.001) with greater prematurity associated with greater mass (r = −0.22, P=0.03). Preterm-born individuals had short left ventricles with small internal diameters and a displaced apex. Ejection fraction was preserved (P>0.99), but both longitudinal systolic (peak strain, strain rate, and velocity, P<0.001) and diastolic (peak strain rate and velocity, P<0.001) function and rotational (apical and basal peak systolic rotation rate, P =0.05 and P =0.006; net twist angle, P=0.02) movement were significantly reduced. A diagnosis of preeclampsia during the pregnancy was associated with further reductions in longitudinal peak systolic strain in the offspring (P=0.02, n=29). Conclusions— Individuals born preterm have increased left ventricular mass in adult life. Furthermore, they exhibit a unique 3-dimensional left ventricular geometry and significant reductions in systolic and diastolic functional parameters. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT01487824.Background— Preterm birth leads to an early switch from fetal to postnatal circulation before completion of left ventricular in utero development. In animal studies, this results in an adversely remodeled left ventricle. We determined whether preterm birth is associated with a distinct left ventricular structure and function in humans. Methods and Results— A total of 234 individuals 20 to 39 years of age underwent cardiovascular magnetic resonance. One hundred two had been followed prospectively since preterm birth (gestational age=30.3±2.5 week; birth weight=1.3±0.3 kg), and 132 were born at term to uncomplicated pregnancies. Longitudinal and short-axis cine images were used to quantify left ventricular mass, 3-dimensional geometric variation by creation of a unique computational cardiac atlas, and myocardial function. We then determined whether perinatal factors modify these left ventricular parameters. Individuals born preterm had increased left ventricular mass (66.5±10.9 versus 55.4±11.4 g/m2; P 0.99), but both longitudinal systolic (peak strain, strain rate, and velocity, P <0.001) and diastolic (peak strain rate and velocity, P <0.001) function and rotational (apical and basal peak systolic rotation rate, P =0.05 and P =0.006; net twist angle, P =0.02) movement were significantly reduced. A diagnosis of preeclampsia during the pregnancy was associated with further reductions in longitudinal peak systolic strain in the offspring ( P =0.02, n=29). Conclusions— Individuals born preterm have increased left ventricular mass in adult life. Furthermore, they exhibit a unique 3-dimensional left ventricular geometry and significant reductions in systolic and diastolic functional parameters. Clinical Trial Registration— URL: . Unique identifier: [NCT01487824][1]. # Clinical Perspective {#article-title-37} [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT01487824&atom=%2Fcirculationaha%2F127%2F2%2F197.atom

“3D Fusion” Echocardiography Improves 3D Left Ventricular Assessment: Comparison with 2D Contrast Echocardiography

Three‐dimensional fusion echocardiography (3DFE) is a novel postprocessing approach that utilizes imaging data acquired from multiple 3D acquisitions. We assessed image quality, endocardial border definition, and cardiac wall motion in patients using 3DFE compared to standard 3D images (3D) and results obtained with contrast echocardiography (2DC).

CMR right ventricular strain assessment using feature tracking cine images: agreement with echocardiography

Right ventricular strain assessment by feature tracking from cine images shows acceptable levels of agreement with echocardiography

Lost without Occam's razor: Escherichia coli tricuspid valve endocarditis in a non-intravenous drug user

The unusual case of a 31-year-old woman who developed tricuspid valve endocarditis with positive blood cultures for Escherichia coli is presented. The patient had no underlying cardiac disease or predisposing conditions that could have made her susceptible to the native valve infection. Despite a lengthy course of intravenous antibiotics only a partial response was achieved. The patient underwent cardiac surgery and had a good postoperative recovery.

Austrian syndrome: a case report and review of the literature

A usually fit and well 69-year-old woman presented with headache and altered consciousness. Initial clinical findings and investigations were consistent with a diagnosis of pneumococcal meningitis and pneumonia. Cultures of blood and cerebrospinal fluid grew Streptococcus pneumoniae. The patient continued to spike temperatures and developed cardiac failure. A transoesophageal echocardiogram demonstrated a large vegetation of the aortic valve causing severe aortic regurgitation. A diagnosis of Austrian syndrome, the triad of pneumococcal meningitis, pneumonia and endocarditis, was made. The patient has completed a course of appropriate antibiotic therapy and is awaiting aortic valve surgery.

Incremental diagnostic role of cardiac MRI in young-middle aged patients with high-grade atrio-ventricular block

Background Atrio-ventricular (AV) block is a common bradyarrhythmia in the elderly, but is a rare event in young or middle-aged adults, often leading to pacemaker implantation without further investigation, though underlying aetiology influences both treatment strategies and prognosis. Cardiovascular magnetic resonance (CMR) has the potential to identify an underlying aetiology for AV block, over and above transthoracic echocardiogram (TTE), which is offered as the first imaging technique. We sought to assess the diagnostic additive role of CMR in young and middle aged adults (18-60 years) with high-grade AV block and to determine which findings on CMR best predict clinical impact.

005 Non-invasive stress imaging as a gatekeeper to complete revascularisation in stemi patients with moderate bystander disease at primary percutaneous coronary intervention

Introduction 40% of patients presenting with STEMI have multivessel disease (MVD). Current international guidelines recommend revascularisation of the culprit artery only. However recent trials (PRAMI/CVLPRIT) have shown a superiority of complete in-hospital revascularisation. Objective: Assess the role of non-invasive stress imaging as a gatekeeper to complete revascularisation in STEMI patients with moderate bystander disease. Methods A registry study of consecutive patients who underwent Primary Percutaneous Coronary Intervention (P-PCI) of the culprit artery. Significant MVD was defined as non-culprit stenosis ≥50% in large proximal epicardial vessel, or ≥75% elsewhere (moderate if 50–74% stenosis in large proximal epicardial vessel, or 75–94% elsewhere). Non-invasive stress imaging was performed at 4 weeks. Patients with severe or critical bystander disease were excluded from the study. A simple cost analysis model was built for UK and USA. Results 1,167 patients were included (74% males, 64 years), 33% demonstrating MVD. 40% of MVD underwent stress CMR, and 36% a stress echocardiogram. The remaining 93 patients underwent direct revascularisation or were lost to follow up. Only 47% had evidence of inducible myocardial ischaemia in moderate bystander coronary artery disease (61/157 in stress CMR and 78/141 in stress echocardiogram). When PCI in MVD is performed only in the presence of inducible myocardial ischemia, there is saving. (UK or US). Conclusions <50% patients with moderate MVD at PPCI have inducible myocardial ischemia in the moderate bystander disease. Non-invasive stress imaging as a gatekeeper to complete revascularisation, may potentially reduce the number of PCIs, also resulting in a cheaper management strategy.

3 Clinical utility of cardiac MRI in young-middle aged patients with high-grade atrio-ventricular block

Background Atrio-ventricular (AV) block is a rare event in young-middle aged adults, often leading to pacemaker implantation without further investigation. We sought to assess the clinical utility of CMR in young-middle aged adults with high-grade AV block. Methods We retrospectively analysed the CMR registry to collect data on consecutive high-grade AV block patients (18–60yrs) referred for CMR (September 2012–November 2015). High-grade AVB was defined as Mobitz II 2nd degree or complete AVB. All patients underwent a transthoracic echocardiogram (TTE) and a comprehensive CMR protocol (cine and late gadolinium enhancement, LGE). A change in diagnosis was defined as a new diagnosis compared to a multi-parametric pre-CMR diagnosis (based on clinical, ECG and TTE data). Results We identified 34 patients (20 male, mean age 44 ± 12 years); 12 patients (34%) had II degree AVB and 22 (66%) complete AVB. Patients were referred to CMR for suspected ischaemic heart disease (IHD) in 4 patients (11%) and non ischaemic heart disease (NIHD) in 24 (71%); in 6 patients (18%) pre-CMR diagnosis was unclear. CMR showed IHD in 3 patients (9%) and NIHD in 11 patients (32%); a structurally normal heart was found in 18 patients (53%) and non-specific findings in 2 (6%) (Table 1) (Figure 1). LGE was found in 12 patients (34%), with predominant mid-wall pattern (58%). There was moderate agreement between CMR and TTE final diagnosis (Cohen’s kappa 0.435, p 0.001). CMR determined a change in diagnosis in 14 patients (40%). Abstract 3 Figure 1 CMR findings. Post-contrast four chamber long-axis (1A) and short-axis (1B) view showing structurally normal heart. Post-contrast four chamber long-axis (2A) and short-axis (2B) view showing epicardial LGE in the basal to mid-cavity lateral wall (white arrow) in a patient with myocarditis. Post-contrast four chamber long-axis (3A) and short-axis (3B) view showing transmural myocardial LGE in the basal to apical lateral wall in a patient with left ventricular non compaction Conclusions CMR was diagnostic in 94% of young-middle aged patients presenting with high grade AVB. As compared to a multi-parametric pre-CMR diagnosis, CMR led to a change in diagnosis in 40% of patients. Abstract 3 Table 1 CMR diagnosis CMR diagnosis n = 3 4 Ischaemic Heart Disease, n (%) 3 (9) Non-ischaemic Heart Disease, n (%) 11 (32) Structurally Normal Heart, n (%) 18 (53) Non-specific Findings, n (%) 2 (6)

Cardiovascular magnetic resonance imaging in patients with MR-conditional devices: a UK tertiary centre experience on image quality and change in patients management

Background Cardiovascular magnetic resonance (CMR) examinations is increasingly used in daily clinical practice. Conventional pacemakers and implantable cardioverter-defibrillators (ICD) have always been regarded as a contraindication to MR imaging. However the introduction of MR-conditional systems have significantly improved access to MR examinations. Limited data exists regarding indications and management outcomes and impact of different cardiac rhythm devices on image quality