Pfizer BNT 162b2 COVID-19 vaccine-induced fulminant myopericarditis: A case study.

The use of mRNA COVID-19 vaccine can on rare occasions cause life-threatening, fulminant myopericarditis. This case report demonstrates previously reported benefit of early use of venoarterial extracorporeal membrane oxygenation mechanical assistance and supports the use of intravenous highly purified immunoglobulin pharmacotherapy to help achieve a good clinical outcome.

The Burden of Cardiac Implantable Electronic Device Checks in the Peri-MRI Setting: The CHECK-MRI Study.

BACKGROUND: Most modern cardiac implantable electronic device (CIED) systems are now compatible with magnetic resonance imaging (MRI) scans. The requirement for both pre- and post-MRI CIED checks imposes significant workload to the cardiac electrophysiology service. Here, we sought to determine the burden of CIED checks associated with MRI scans. METHODS: We identified all CIED checks performed peri-MRI scans at our institution over a 3-year period between 1 July 2017 to 30 June 2020, comprising three separate financial years (FY). Device check reports, MRI scan reports and clinical summaries were collated. The workload burden was determined by assessing the occasions and duration of service. Analysis was performed to determine cost burden/projections for this service and identify factors contributing to the workload. RESULTS: A total of 739 CIED checks were performed in the peri-MRI scan setting (370 pre- and 369 post-MRI scan), including 5% (n=39) that were performed outside of routine hours (weekday <8 am or >5 pm, and weekends). MRIs were performed for 295 patients (75±13 years old, 64% male) with a CIED (88% permanent pacemaker, and 12% high voltage device), including 49 who had more than one MRI scan. The proportion of total MRI scans for patients with a CIED in-situ increased each FY (from 0.5% of all MRIs in FY1, to 0.9% in FY2, to 1.0% in FY3). The weekly workload increased (R2=0.2, p<0.001), but with week-to-week variability due to ad hoc scheduling (209 days with only one MRI vs 78 days with ≥2 MRIs for CIED patients). The projected annual cost of this service will increase to AUD$161,695 in 10 years for an estimated annual 546 MRI scans for CIED patients. CONCLUSIONS: There is an increasing workload burden and expense associated with CIED checks in the peri-MRI setting. Appropriate budgeting, staff allocation and standardisation of automated CIED pre-programming features among manufacturers are urgently needed.

Cardiovascular magnetic resonance imaging characteristics in patients with methamphetamine-associated cardiomyopathy.

BACKGROUND: Methamphetamine-associated cardiomyopathy (MA-CMP) is an increasingly recognised aetiology of cardiomyopathy. Cardiovascular magnetic resonance (CMR) is a specialised cardiac imaging modality commonly used in assessment of cardiomyopathy. We aimed to identify specific CMR features associated with MA-CMP. METHODS: A retrospective cohort study of CMR scans was performed in a single centre between January 2015 and December 2020. Thirty patients with MA-CMP who had undergone CMR were identified. MA-CMP was defined as those with a history of significant methamphetamine use hospitalised with acute decompensated heart failure (other causes of cardiomyopathy excluded). A retrospective analysis of index admission CMRs was performed. All studies were performed on a 1.5 T CMR scanner. RESULTS: The mean age of MA-CMP patients was 43.7 ± 7.5 years, and 86.7% were male. The mean left ventricular (LV) volume obtained in this cohort was consistent with severe LV dilatation (LV end-diastolic volume (334 ± 99 ml); LV end-systolic volume: 269 ± 98 ml), whilst the right ventricular (RV) volume indicated moderate-to-severe dilatation (RV end-diastolic volume: 272 ± 91 ml; RV end-systolic volume: 173 ± 82 ml). Mean LV ejection fraction (20.9 ± 9.2%) indicated severe LV dysfunction, with moderate-to-severe RV dysfunction also detected (RV ejection fraction: 29.4 ± 13.4%). 22 patients (73.3%) had myocardial late gadolinium enhancement (LGE), of which 59.1% were located in the mid-wall, with all of these involving the interventricular septum. 22.7% displayed localised regions of sub-endocardial LGE in a variety of locations, and 18.2% had transmural regions of LGE that were located in the inferior and inferolateral segments. 6 patients (20%) had intracardiac thrombus (4 LV, 2 both LV and RV). CONCLUSION: MA-CMP was associated with severe biventricular dilatation and dysfunction, with a high prevalence of intraventricular thrombus. This cohort study highlights that MA-CMP patients have a high prevalence of CMR findings.

Multimodality Tachycardia-Induced Stress Testing Predicts a Low-Risk Group for Early Cardiovascular Mortality After Renal Transplantation.

BACKGROUND: Cardiovascular events remain a major cause of death in kidney transplant recipients. The optimal noninvasive workup to prevent peritransplant cardiac mortality remains contentious. METHODS: We conducted a retrospective analysis to assess the renal transplantation cardiovascular assessment protocol within a single-center population over a 5-year period. Asymptomatic patients aged less than 45 years with no history of cigarette smoking, without diabetes mellitus, and dialysis-dependent for less than 24 months did not undergo cardiac testing before listing. All other asymptomatic patients underwent a noninvasive, tachycardia-induced stress test, where a target heart rate of 85% predicted for age and gender was required. The primary endpoints were rates of acute myocardial infarction (AMI) and cardiovascular death at 30 days after renal transplantation. RESULTS: Between 2015 and 2019, 380 recipients underwent cardiac evaluation: 79 (20.8%) were deemed low cardiovascular risk and placed on the renal transplant waitlist without further assessment; 270 (71.1%) underwent a tachycardia-induced stress test; and 31 (8.1%) were deemed high risk and proceeded directly to invasive coronary angiography (ICA). In the 5-year follow-up, 3 patients (0.8%) experienced an AMI 30 days after renal transplantation, all of which occurred in the high-risk "direct to ICA" cohort. No events were documented in the low-risk cohort or in patients who had a negative tachycardia-induced stress test. There were no cardiovascular deaths within 30 days after transplantation. CONCLUSION: A negative tachycardia-induced cardiac stress test, achieving 85% of predicted heart rate, was associated with a 0% AMI rate and no cardiovascular deaths at 30 days after renal transplantation.

Long-Term Impact of Arteriovenous Fistula Ligation on Cardiac Structure and Function in Kidney Transplant Recipients: A 5-Year Follow-Up Observational Cohort Study.

Background: The long-term effects of arteriovenous fistula (AVF) ligation on cardiovascular structure following kidney transplantation remain uncertain. A prospective randomized, controlled trial (RCT) examined the effect of AVF ligation at 6 months on cardiovascular magnetic resonance imaging (CMR)-derived parameters in 27 kidney transplant recipients compared with 27 controls. A mean decrease in left ventricular mass (LVM) of 22.1 g (95% CI, 15.0 to 29.1) was observed compared with an increase of 1.2 g (95% CI, -4.8 to 7.2) in the control group (P<0.001). We conducted a long-term follow-up observational cohort study in the treated cohort to determine the evolution of CMR-derived parameters compared with those documented at 6 months post-AVF ligation. Methods: We performed CMR at long-term follow-up in the AVF ligation observational cohort from our original RCT published in 2019. Results were compared with CMR at 6 months postintervention. The coprimary end point was the change in CMR-derived LVM and LVM index at long-term follow-up from imaging at 6 months postindex procedure. Results: At a median of 5.1 years (interquartile range, 4.7-5.5 years), 17 patients in the AVF ligation group were studied with repeat CMR with a median duration to follow-up imaging of 5.1 years (IQR, 4.7-5.5 years). Statistically significant further reductions in LVM (-17.6±23.0 g, P=0.006) and LVM index (-10.0±13.0 g/m2, P=0.006) were documented. Conclusions: The benefit of AVF ligation on LVM and LVM index regression appears to persist long term. This has the potential to lead to a significant reduction in cardiovascular mortality.

Aortic distensibility is associated with both resting and hyperemic coronary blood flow.

A large body of evidence demonstrates an independent association between arterial stiffness and prospective risk of cardiovascular events. A reduction in coronary perfusion is presumed to underscore this association; however, studies confirming this are lacking. This study compared invasive measures of coronary blood flow (CBF) with cardiac magnetic resonance (CMR)-derived aortic distensibility (AD). Following coronary angiography, a Doppler FloWire and infusion microcatheter were advanced into the study vessel. Average peak velocity (APV) was acquired at baseline and following intracoronary adenosine to derive coronary flow velocity reserve (CFVR = hyperemic APV/resting APV) and CBF [π × (diameter)2 × APV × 0.125]. Following angiography, patients underwent CMR to evaluate distensibility at the ascending aorta (AA), proximal descending aorta (PDA) and distal descending aorta (DDA). Fifteen participants (53 ± 13 yr) with minor epicardial disease (maximum stenosis <30%) were enrolled. Resting CBF was 44.1 ± 11.9 mL/min, hyperemic CBF was 143.8 ± 37.4 mL/min, and CFVR was 3.15 ± 0.48. AD was 3.89 ± 1.72·10-3mmHg-1 at the AA, 4.08 ± 1.80·10-3mmHg-1 at the PDA, and 4.42 ± 1.67·10-3mmHg-1 at the DDA. All levels of distensibility correlated with resting CBF (R2 = 0.350-0.373, P < 0.05), hyperemic CBF (R2 = 0.453-0.464, P < 0.01), and CFVR (R2 = 0.442-0.511, P < 0.01). This study demonstrates that hyperemic and, to a lesser extent resting CBF, are significantly associated with measures of aortic stiffness in patients with only minor angiographic disease. These findings provide further in vivo support for the observed prognostic capacity of large artery function in cardiovascular event prediction.NEW & NOTEWORTHY Cardiac magnetic resonance-derived aortic distensibility is associated with invasive measures of coronary blood flow. Large artery function is more strongly correlated with hyperemic than resting blood flow. Increased stiffness may represent a potential target for novel antianginal medications.

Cardiac involvement in idiopathic inflammatory myopathies detected by cardiac magnetic resonance imaging.

Cardiac involvement in idiopathic inflammatory myopathies (IIM) adversely affects prognosis but is commonly sub-clinical. Cardiac magnetic resonance imaging (CMR) is an effective imaging modality for detecting myocardial inflammation and fibrosis but its use as a screening tool for cardiac disease in IIM has not been fully explored. Nineteen patients with IIM without cardiac symptoms underwent CMR using a specific cardiomyopathy protocol including specific sequences detecting focal and diffuse myocardial fibrosis. 9/19 patients demonstrated late gadolinium enhancement (LGE (3/9 right ventricular insertion, 1/9 sub-endocardial, 7/9 mid-wall/sub-epicardial)). T1 mapping was performed in 15 patients. In total, 7/15 had elevated native T1 values, of which four had detected LGE. Myocardial fibrosis was frequently detected in IIM patients without cardiac history. Detection of LGE and elevated T1 values may have negative prognostic implications. Longitudinal studies determining whether early or augmented treatment has a role in patients with sub-clinical cardiac involvement are needed.Key Points• Cardiac involvement in myositis adversely affects prognosis.• Cardiac magnetic resonance imaging is an effective tool for detecting cardiac involvement.• T1 mapping is a technique which detects diffuse myocardial inflammation and fibrosis.• In our study, focal and diffuse myocardial fibrosis was frequently found in myositis patients without cardiac symptoms.

Effects of Arteriovenous Fistula Ligation on Cardiac Structure and Function in Kidney Transplant Recipients.

BACKGROUND: Cardiovascular morbidity and mortality remain high in recipients of a kidney transplant. The persistence of a patent arteriovenous fistula (AVF) after transplantation may contribute to ongoing maladaptive cardiovascular remodeling. The ability to reverse this maladaptive remodeling by ligation of this AVF is unknown. We conducted the first randomized controlled trial to evaluate the effect of AVF ligation on cardiac structure and function in stable kidney transplant recipients. METHODS: In this randomized controlled trial, kidney transplant recipients (>12 months after transplantation with stable graft function) were randomized to AVF ligation or no intervention. All participants underwent cardiac magnetic resonance imaging at baseline and at 6 months. The primary outcome was the change in left ventricular (LV) mass. Secondary outcomes included changes in LV volumes, left and right atrial areas, LV ejection fraction, NT-proBNP (N-terminal pro-B-type natriuretic peptide) levels, cardiac output/index, brachial flows (ipsilateral to AVF), and pulmonary artery velocity. RESULTS: A total of 93 patients were screened, of whom 64 met the inclusion criteria and were randomized to the AVF ligation (n=33) or control (n=31) group. Fifty-four participants completed the study: 27 in the AVF ligation group and 27 in the control group. On the second cardiac magnetic resonance scan, a mean decrease of 22.1 g (95% CI, 15.0-29.1) was observed in LV mass in the AVF ligation group compared with a small increase of 1.2 g (95% CI, -4.8 to 7.2) in the control group ( P<0.001). Significant decreases in LV end-diastolic volumes, LV end-systolic volumes, cardiac output, cardiac index, atrial volumes, and NT-proBNP were also seen in the AVF closure group ( P<0.01). No significant changes were observed in LV ejection fraction ( P=0.93) and pulmonary artery velocity ( P=0.07). No significant complications were noted after AVF ligation. No changes in estimated glomerular filtration rate or systolic and diastolic blood pressures were observed between cardiac magnetic resonance scans. CONCLUSIONS: Elective ligation of patent AVF in adults with stable kidney transplant function resulted in clinically significant reduction of LV myocardial mass. CLINICAL TRIAL REGISTRATION: Australian and New Zealand Clinical Trials Registry URL: https://www.anzctr.org.au . Unique Identifier: ACTRN12613001302741.

Electroanatomical Remodeling of the Atria in Obesity: Impact of Adjacent Epicardial Fat.

OBJECTIVES: The aims of the study were to characterize: 1) electrical and electroanatomical remodeling in patients with atrial fibrillation (AF) with obesity; and 2) the impact of epicardial fat depots on adjacent atrial tissue. BACKGROUND: Obesity is associated with an increased risk of AF. METHODS: A total of 115 patients with AF who underwent AF ablation were screened. After exclusion, 26 patients were divided into 2 groups (obese: body mass index [BMI] ≥27 kg/m2 and reference: BMI <27 kg/m2). They underwent cardiac magnetic resonance (CMR) imaging and electroanatomic mapping of the left atrium (LA) in sinus rhythm before AF ablation. Atrial and ventricular epicardial adipose tissue (EAT) were assessed by CMR. The following electrophysiological parameters were assessed: global and regional voltage, conduction velocity (CV), electrogram fractionation, and CV heterogeneity. In addition, the regional relationship between LA EAT depots and the electrophysiological substrate was evaluated. RESULTS: The BMIs of the obese and reference groups were 30.2 ± 2.6 and 25.2 ± 1.3 kg/m2, respectively (p < 0.001). There was no difference in the left ventricular ejection fraction and a nonsignificant increase in LA size with obesity. Obesity was associated with increase in all measures of EAT (p < 0.05), with a predominant distribution adjacent to the posterior LA and the atrioventricular groove. Obesity was associated with reduced global CV (0.86 ± 0.31 m/s vs. 1.26 ± 0.29 m/s; p < 0.001), with a nonsignificant increase in conduction heterogeneity (p = 0.10), increased fractionation (54 ± 17% vs. 25 ± 10%; p < 0.001), and regional alteration in voltage (p < 0.001). Although the global LA voltage was preserved, there was greater voltage heterogeneity (p = 0.001) and increased low-voltage areas (13.9% vs. 3.4%; p < 0.001) in the obese group compared with the reference group. The low voltage areas were predominantly seen in the posterior and/or inferior LA, which was similar to location of EAT on CMR imaging. Among various measures of obesity, LA EAT volume correlated best with posterior LA fractionation (r2 = 0.55 for LA EAT volume vs. r2 = 0.36 for BMI) and CV (r2 = 0.31 for LA EAT volume vs. r2 = 0.22 for BMI). CONCLUSIONS: Obesity is associated with electroanatomical remodeling of the atria, with areas of low voltage, conduction slowing, and greater fractionation of electrograms. These changes were more pronounced in regions adjacent to epicardial fat depots, which suggested a role for fat depots in the development of the AF substrate.

Effects of renal sympathetic denervation on myocardial structure, function and perfusion: A serial CMR study.

BACKGROUND AND AIMS: Echocardiographic studies have shown improvements in cardiac indices associated with renal sympathetic denervation (RDN), however, the benefits on myocardial perfusion have never been assessed. This trial was designed to study the effects of RDN on myocardial perfusion using cardiac magnetic resonance (CMR) imaging. METHODS: A total of 14 patients with resistant hypertension were recruited for RDN and myocardial perfusion, alongside other CMR indices, was assessed at baseline and at 6 months. RESULTS: RDN showed significant reduction of mean office blood pressures from 181/100 ±â€¯19/16 mmHg to 147/85 ±â€¯19/17 mmHg, 6 months after the procedure (p < 0.0001). This was combined with significant improvement in regional aortic distensibility (p < 0.02) and associated with trends of improved myocardial perfusion reserve index (baseline = 2.2 ±â€¯1; 6 months = 2.9 ±â€¯1 units) (p = 0.08). Left ventricular end systolic volume index decreased from baseline to 6 months post procedure, 27 ±â€¯13 ml/m2vs. 22 ±â€¯10 ml/m2 (p = 0.03), but there was no significant change in left ventricular end diastolic volume index (p = 0.09). There was significant improvement in mean left ventricular ejection fraction from 68 ± 10% to 72 + 9%, 6 months post procedure (p = 0.04). T1 mapping failed to detect fibrosis in these patients at baseline and therefore no change was noted, however, extracellular volume percent improved from 46 ±â€¯4% at baseline to 41 ±â€¯8% at 6 months (p = 0.002). CONCLUSIONS: This study demonstrates that renal sympathetic denervation increased myocardial perfusion by 32% as assessed by CMR, and, this was associated with improvements in cardiac volumes and function. Larger well controlled and randomized studies are required to assess the clinical significance of these findings.

Ascending aortic blood flow velocity is increased in children with primary snoring/mild sleep-disordered breathing and associated with an increase in CD8 + T cells expressing TNFα and IFNγ.

Sleep-disordered breathing (SDB) is associated with cardiovascular disease and systemic inflammation in adults but this remains to be explored in children, especially in children with the most common form of SDB, i.e. primary snoring/mild SDB. This pilot study investigated the relationship between the cardiovascular function and inflammation in children with mild SDB. Nineteen participants aged 5-14 years underwent overnight polysomnography, cardiac magnetic resonance imaging (aortic blood flow velocity and left and right ventricular systolic function) and assessment for inflammatory markers (intracellular cytokine analysis of T cells by flow cytometry). Parents also completed the Sleep Disturbances Scale for Children (SDSC). Children with mild SDB exhibited increased ascending aortic peak systolic velocity compared to controls (SDB 119.95 m/s vs. control 101.49 m/s, p < 0.05). No significant group differences were observed for left and right ventricular ejection fraction or mean aortic blood flow velocity from either the ascending aorta or pulmonary artery. Children with mild SDB had increased inflammatory markers as demonstrated by elevated T cell interferon gamma (IFNγ) (SDB 52 ± 4% vs. control 25 ± 3% positive cells, p < 0.005) and tumour necrosis factor alpha (TNFα) (SDB 39 ± 4% vs. control 20 ± 2% positive cells, p < 0.005) expression from CD8+ cells. A strong positive correlation was observed between ascending aorta peak blood flow velocity and both TNFα and IFNγ (TNFα, r = 0.54, p < 0.03; IFNγ, r = 0.63, p < 0.005, respectively). Polysomnography revealed that oxygen saturation (SaO2) nadir was significantly lower in children with mild SDB compared to controls (SDB 92.3 ± 2.7% vs. control 94.4 ± 1.6%, p < 0.05). A lower SaO2 nadir was associated with an increased ascending aorta peak systolic velocity (r = - 0.48, p < 0.05). As well, both a lower SaO2 nadir and an increased ascending aorta peak systolic velocity were associated with higher SDSC Sleep-Disordered Breathing and Disorder of Initiating and Maintaining Sleep subscale scores but not the polysomnographic-derived Obstructive Apnea-Hypopnea Index. The finding of elevated ascending aortic peak systolic blood flow velocity and its association with increased inflammatory markers suggests that the profile of cardiovascular changes noted in adult SDB may also occur in children with mild SDB.

Cardiac magnetic resonance assessment of diastolic dysfunction in acute coronary syndrome.

Chest pain is an important presenting symptom. However, few cases of chest pain are diagnosed as acute coronary syndrome (ACS) in the acute setting. This results in frequent inappropriate discharge and major delay in treatment for patients with underlying ACS. The conventional methods of assessing ACS, which include electrocardiography and serological markers of infarct, can take time to manifest. Recent studies have investigated more sensitive and specific imaging modalities that can be used. Diastolic dysfunction occurs early following coronary artery occlusion and its detection is useful in confirming the diagnosis, risk stratification, and prognosis post-ACS. Cardiac magnetic resonance provides a single imaging modality for comprehensive evaluation of chest pain in the acute setting. In particular, cardiac magnetic resonance has many imaging techniques that assess diastolic dysfunction post-coronary artery occlusion. Techniques such as measurement of left atrial size, mitral inflow, and mitral annular and pulmonary vein flow velocities with phase-contrast imaging enable general assessment of ventricular diastolic function. More novel imaging techniques, such as T2-weighted imaging for oedema, T1 mapping, and myocardial tagging, allow early determination of regional diastolic dysfunction and oedema. These findings may correspond to specific infarcted arteries that may be used to tailor eventual percutaneous coronary artery intervention.

Renal sympathetic denervation increases renal blood volume per cardiac cycle: a serial magnetic resonance imaging study in resistant hypertension.

AIM: Preclinical studies have demonstrated improvements in renal blood flow after renal sympathetic denervation (RSDN); however, such effects are yet to be confirmed in patients with resistant hypertension. Herein, we assessed the effects of RSDN on renal artery blood flow and diameter at multiple time points post-RSDN. METHODS AND RESULTS: Patients (n=11) with systolic blood pressures ≥160 mmHg despite taking three or more antihypertensive medications at maximum tolerated dose were recruited into this single-center, prospective, non-blinded study. Magnetic resonance imaging indices included renal blood flow and renal artery diameters at baseline, 1 month and 6 months. In addition to significant decreases in blood pressures (p<0.0001), total volume of blood flow per cardiac cycle increased by 20% from 6.9±2 mL at baseline to 8.4±2 mL (p=0.003) at 1 month and to 8.0±2 mL (p=0.04) 6 months post-procedure, with no changes in the renal blood flow. There was a significant decrease in renal artery diameters from 7±2 mm at baseline to 6±1 mm (p=0.03) at 1 month post-procedure. This decrease was associated with increases in maximum velocity of blood flow from 73±20 cm/s at baseline to 78±19 cm/s at 1 month post-procedure. Notably, both parameters reverted to 7±2 mm and 72±18 cm/s, respectively, 6 months after procedure. CONCLUSION: RSDN improves renal physiology as evidenced by significant improvements in total volume of blood flow per cardiac cycle. Additionally, for the first time, we identified a transient decrease in renal artery diameters immediately after procedure potentially caused by edema and inflammation that reverted to baseline values 6 months post-procedure.

The predictive capabilities of a novel cardiovascular magnetic resonance derived marker of cardiopulmonary reserve on established prognostic surrogate markers in patients with pulmonary vascular disease: results of a longitudinal pilot study.

BACKGROUND: No unified method exists to effectively predict and monitor progression of pulmonary arterial hypertension (PAH). We assessed the longitudinal relationship between a novel marker of cardiopulmonary reserve and established prognostic surrogate markers in patients with pulmonary vascular disease. METHODS AND RESULTS: Twenty participants with confirmed (n = 14) or at high risk (n = 6) for PAH underwent cardiovascular magnetic resonance (CMR) at baseline and after ~6 months of guideline-appropriate management. Ten PAH participants underwent RHC within 48 h of each CMR. RHC (mean pulmonary arterial pressure, mPAP; pulmonary vascular resistance index, PVRI; cardiac index, CI) and phase-contrast CMR (mean pulmonary arterial blood flow velocity, meanPAvel) measurements were taken at rest and during continuous adenosine infusion (70/140/210 mcg/kg/min). Initial meanPAvel's (rest and hyperemic) were correlated with validated surrogate prognostic parameters (CMR: RV ejection fraction, RVEF; RV end systolic volume indexed, RVESVI; RHC: PVRI, CI; biomarker: NT-pro brain natriuretic peptide, NTpBNP; clinical: 6-min walk distance, 6MWD), a measure of pulmonary arterial stiffness (elastic modulus) and volumetric estimation of RV ventriculoarterial (VA) coupling. Changes in meanPAvel's were correlated with changes in comparator parameters over time. At initial assessment, meanPAvel at rest correlated significantly with PVRI (inversely), CI (positively) and elastic modulus (inversely) (R 2 > 0.37,P < 0.05 for all), whereas meanPAvel at peak hyperemia correlated significantly with PVRI, RVEF, RVESVI, 6MWD, elastic modulus and VA coupling (R 2 > 0.30,P < 0.05 for all). Neither resting or hyperemia-derived meanPAvel correlated with NTpBNP levels. Initial meanPAvel at rest correlated significantly with RVEF, RVESVI, CI and VA coupling at follow up assessment (R 2 > 0.2,P < 0.05 for all) and initial meanPAvel at peak hyperemia correlated with RVEF, RVESVI, PVRI and VA coupling (R 2 > 0.37,P < 0.05 for all). Change in meanPAvel at rest over time did not show statistically significant correlation with change in prognostic parameters, while change in meanPAvel at peak hyperemia did show a significant relationship with ΔRVEF, ΔRVESVI, ΔNTpBNP and ΔCI (R 2 > 0.24,P < 0.05 for all). CONCLUSION: MeanPAvel during peak hyperemia correlated with invasive, non-invasive and clinical prognostic parameters at different time points. Further studies with predefined clinical endpoints are required to evaluated if this novel tool is a marker of disease progression in patients with pulmonary vascular disease.

CT sizing for left atrial appendage closure is associated with favourable outcomes for procedural safety.

AIMS: We evaluated the utility of computerized tomography (CT) with respect to sizing work-up for percutaneous left atrial appendage (LAA) closure, and implications for procedural safety and outcomes. METHODS AND RESULTS: Contrast-enhanced multi-detector CT was routinely conducted to guide sizing for LAA closure in addition to transoesophageal echocardiography (TOE). Procedural safety and efficacy were prospectively assessed. Across 73 consecutive cases there were no device-related procedural complications, and no severe leaks. Systematic bias in orifice sizing by TOE vs. CT was significant on retrospective analysis (bias -3.0 mm vs. maximum diameter on CT; bias -1.1 mm vs. mean diameter on CT). Importantly, this translated to an altered device size selection in more than half of all cases, and median size predicted by CT was one interval greater than that predicted by TOE (27 mm vs. 24 mm). Of particular note, gross sizing error by TOE vs. CT was observed in at least 3.4% of cases. Degree of discrepancy between TOE and CT was correlated with LAA orifice eccentricity, orifice size, and left atrial volume. Mean orifice size by CT had the greatest utility for final Watchman device-size selection. CONCLUSIONS: In this single-centre registry of LAA closure, routine incorporation of CT was associated with excellent outcomes for procedural safety and absence of major residual leak. Mean orifice size may be preferable to maximum orifice size. A particular value of CT may be the detection and subsequent avoidance of gross sizing error by 2D TOE that occurs in a small but important proportion of cases.

The evolving role of cardiac magnetic resonance imaging in the assessment of cardiovascular disease.

BACKGROUND: Imaging of the heart is important in the diagnosis and follow-up of a broad range of cardiac pathology. The authors discuss the growing role of cardiac magnetic resonance imaging (CMR) in cardiology practice and its relevance to primary healthcare. OBJECTIVE: In this article we discuss the advantages of CMR over other imaging modalities, and give a brief description of the common CMR techniques and cardiac pathologies where CMR is especially useful. DISCUSSION: CMR provides specific advantages over other cardiac imaging modalities when evaluating pathology in congenital heart disease, cardiac masses, cardiomyopathies, and in some aspects of ischaemic and valvular heart diseases. The strength of CMR in these pathologies includes its precise ana-tomical delineation of structures, characterisation of myocardial tissue, and accurate, reproducible measurements of blood volume and flow. CMR is used in inpatient and outpatient settings, and is available primarily in major hospitals.

Characterisation of Myocardial Injury via T1 Mapping in Early Reperfused Myocardial Infarction and its Relationship with Global and Regional Diastolic Dysfunction.

BACKGROUND: Cardiovascular magnetic resonance (CMR) advances in imaging techniques, permits the ability to accurately characterise tissue injury post myocardial infarction. Pre-contrast T1 mapping enables this through measurement of pre-contrast T1 relaxation times. We investigate the relationship between T1 characterisation of myocardial injury with global and regional diastolic function. METHODS: Revascularised acute myocardial infarction patients with normal left ventricular (LV) systolic function on TTE were assessed by 1.5T CMR. Acute regional diastolic wall motion abnormalities, global diastolic function measurements, acute segmental damage fraction with LGE and mean segmental pre-contrast T1 values were assessed on matching short axis slices. RESULTS: Forty-four patients were analysed. Mean LVEF was 62.1±9.4%. No difference between NSTEMI (22/44) and STEMI in mean pre-contrast T1 values of infarcted (1025.0±109.2 vs 1011.0±81.6ms, p=0.70), adjacent (948.3±45.3 vs 941.1±46.6ms, p=0.70) and remote (888.8±52.8 vs 881.2±54.5ms, p=0.66) segments was detected. There was no correlation between pre-contrast T1 of infarcted segments with global diastolic dysfunction (E/A, r2=0.216, p=0.06; S/D, r2=0.243, p=0.053; E/E', r2=0.240, p=0.072), but there was significantly positive, moderate correlation with circumferential diastolic strain rate, (r2=0.579, p<0.01) with excellent agreement and reproducibility. CONCLUSION: Cardiac magnetic resonance evaluation of pre-contrast T1 values revealed no difference between NSTEMI and STEMI patients in terms of tissue characterisation post-myocardial infarction. However, pre-contrast T1 of infarcted tissue is significantly correlated with regional diastolic circumferential strain rate.