Quantification of mitral regurgitation in patients with hypertrophic cardiomyopathy using aortic and pulmonary flow data: impacts of left ventricular outflow tract obstruction and different left ventricular segmentation methods

Background

Cardiovascular magnetic resonance (CMR) imaging in patients with hypertrophic cardiomyopathy (HCM) enables the assessment of not only left ventricular (LV) hypertrophy and scarring but also the severity of mitral regurgitation. CMR assessment of mitral regurgitation is primarily based on the difference between LV stroke volume (LVSV) and aortic forward flow (Ao) measured using the phase-contrast (PC) technique. However, LV outflow tract (LVOT) obstruction causing turbulent, non-laminar flow in the ascending aorta may impact the accuracy of aortic flow quantification, leading to false conclusions regarding mitral regurgitation severity. Thus, we decided to quantify mitral regurgitation in patients with HCM using Ao or, alternatively, main pulmonary artery forward flow (MPA) for mitral regurgitation volume (MRvol) calculations.

Methods

The analysis included 143 prospectively recruited subjects with HCM and 15 controls. MRvol was calculated as the difference between LVSV computed with either the inclusion (LVSV_incl) or exclusion (LVSV_excl) of papillary muscles and trabeculations from the blood pool and either Ao (MRvol_Aoi or MRvol_Aoe) or MPA (MRvol_MPAi or MRvol_MPAe). The presence or absence of LVOT obstruction was determined based on Doppler echocardiography findings.

Results

MRvol_Aoi was higher than MRvol_MPAi in HCM patients with LVOT obstruction [47.0 ml, interquartile range (IQR)?=?31.5–60.0 vs. 35.5 ml, IQR?=?26.0–51.0; p <?0.0001] but not in non-obstructive HCM patients (23.0 ml, IQR?=?16.0–32.0 vs. 24.0 ml, IQR?=?15.3–32.0; p?=?0.26) or controls (18.0 ml, IQR?=?14.3–21.8 vs. 20.0 ml, IQR?=?14.3–22.0; p?=?0.89). In contrast to controls and HCM patients without LVOT obstruction, in HCM patients with LVOT obstruction, aortic flow-based MRvol (MRvol_Aoi) was higher than pulmonary-based findings (MRvol_MPAi) (bias?=?9.5 ml; limits of agreement: ?11.7–30.7 with a difference of 47 ml in the extreme case). The differences between aortic-based and pulmonary-based MRvol values calculated using LVSV_excl mirrored those derived using LVSV_incl. However, MRvol values calculated using LVSV_excl were lower in all the groups analyzed (HCM with LVOT obstruction, HCM without LVOT obstruction, and controls) and with all methods of MRvol quantification used (p?≤?0.0001 for all comparisons).

Conclusions

In HCM patients, LVOT obstruction significantly affects the estimation of aortic flow, leading to its underestimation and, consequently, to higher MRvol values than those obtained with MPA-based MRvol calculations.

     

Quantification of mitral regurgitation during percutaneous mitral valve repair: added value of simultaneous hemodynamic and 3D echocardiographic assessment

The objective of this study was to investigate the usefulness of intraprocedural hemodynamic monitoring for MR evaluation during pMRV. Assessment of mitral regurgitation (MR) during percutaneous mitral valve repair (pMVR) procedure is challenging. 3D color Doppler allows exact quantification of MR, but is technically demanding. Sixty patients with moderate to severe MR (14 with structural and 46 functional MR) were included in the study. Intraprocedural pressure curves were continuously obtained in the left atrium (LA) and left ventricle (LV). Transesophageal echocardiography was performed using 3D color Doppler derived mean vena contracta area (VCA_mean) and mitral regurgitation volume (RegVol) to quantify MR severity before and after each clip implantation. In the entire patient group, strongest correlations were observed firstly between VCA and the raise of the ascending limb of the left atrial V pressure wave (V_ascend; r?=?0.58, p?<?0.001) and secondly between the difference of peak V wave pressure and mean LA pressure divided by systolic LV pressure [(V_peak???LA_mean)???LV_systole; r?=?0.53, p?<?0.001]. In patients with structural MR, the highest area under the ROC curve for prediction of mild MR (VCA_mean < 0.2 cm² and RegVol?<?30 ml) after clip implantation was found for V_ascend (AUC 0.89, p?<?0.001) whereas in functional MR calculation of (V_peak???LA_mean)???LV_systole showed the highest predictive value (AUC 0.69, p?=?0.003). Invasive pressure monitoring can give a direct feedback with regard to the success of clip placement during pMVR.     

An integrated approach to determine left atrial volume, mass and function in hypertrophic cardiomyopathy by two-dimensional echocardiography

Methods

The study included 25 hypertrophic cardiomyopathy (HCM) patients (15 non-obstructive and 10 obstructive) and 25 controls for assessment of left atrial (LA) volume, mass and function by two-dimensional echocardiography. Measurement included mean LA diameter (LAD), LA mass = {(mean LAD + anterior LA wall + posterior LA wall)³ ? mean LAD³} × 0.8 + 0.6, LA volume = [(8/3 π L · A1 · A2), where L is LA length, A1 and A2 are LA area in 4-chambers and 2-chambers, respectively] including maximum (V _max), minimum (V _min), and pre-atrial contraction (V _pre-A), total atrial stroke volume (TA-SV), TA emptying fraction (TA-EF), active atrial SV (AA-SV), AA-EF, passive atrial SV (PA-SV), PA-EF, atrial expansion index (AEI), and LA kinetic energy (LA-KE) = ½ × AA-SV × P × V².

Results

LAD, LA mass, V _max, V _min, and V _pre-A were significantly higher in HCM than controls. TA-SV and TA-EF were comparable in both HCM subgroups and controls. AA-SV and LA-KE were significantly higher in both HCM subgroups than controls. LA-KE was significantly higher in obstructive HCM than non-obstructive (P < 0.001). PA-EF and AEI were significantly lower in obstructive HCM than controls (P < 0.05).

Conclusion

HCM is associated with increased LA size and augmented LA pump function especially obstructive type. LA conduit and reservoir functions are impaired in obstructive HCM.     

Value of low-dose dobutamine stress echocardiography on defining true severe low gradient aortic stenosis in patients with preserved left ventricular ejection fraction

Low-dose dobutamine stress echocardiography (DSE) is a valuable tool to distinguish true-severe (TS) from pseudo-severe (PS) low gradient aortic valve stenosis (LGAS) in patients with reduced left ventricular ejection fraction (LVEF). However, only scanty studies reported the clinical utility of DSE in differentiating TS-LGAS patients with preserved LVEF. We investigated the clinical utility of DSE in LGAS patients with preserved LVEF and the echocardiographic determinants suggestive of TS-LGAS. 130 consecutive LGAS patients [indexed aortic valve area (AVA)?≤?0.6cm²/m² and mean trans-aortic pressure gradient (PG_mean)?<?40mmHg] with preserved (≥?50%, n?=?63) and reduced (<?50%, n?=?67) LVEF were included. DSE defined TS-LGAS (projected AVA?≤?1 cm²) in 61.2% patients with reduced LVEF and in 68.3% patients with preserved LVEF. Multivariate logistic regression analysis showed that baseline AVA was an independent determinant of TS-LGAS both in LVEF?≥?50% (OR 0.45, P?=?0.004) and LVEF?<?50% groups (OR 0.55, P?=?0.005). Reduced septal and lateral mitral annular plane systolic excursion (MAPSE, OR 0.72 and 0.75, P?=?0.013 and 0.016) and septal TDI-s´ were significantly associated with TS-LGAS in patients with LVEF?≥?50%. Higher systolic pulmonary artery pressure (SPAP, OR 1.43, P?=?0.045) was associated with TS-LGAS in patients with LVEF?<?50%. DSE is useful to define TS-LGAS also in patients with preserved LVEF. Lower baseline AVA values are linked with TS-LGAS in both patients with reduced and preserved LVEF. Reduced MAPSE and septal TDI-s´ are suggestive of TS-LGAS in patients with preserved LVEF, while higher SPAP is associated with TS-LGAS in patients with reduced LVEF.     

CMR assessment and clinical outcomes of hypertrophic cardiomyopathy with or without ventricular remodeling in the end-stage phase

End-stage phase of hypertrophic cardiomyopathy (ES-HCM) is a recognized part of HCM disease spectrum. Information on cardiac magnetic resonance (CMR) studies for ES-HCM especially for those without ventricular remodeling has been limited. We aimed to evaluate the morpho-functional and tissue features of ES-HCM with or without ventricular remodeling and to explore CMR prognostic value in these patients. We analysed CMR scans of sixty-three ES-HCM patients and divided them into those with ventricular dilatation (D-ES, n?=?41) and those with normal ventricular size (N-ES, n?=?22). Cox proportional hazards models were used to assess the association between CMR parameters and outcomes. Patients in D-ES showed hypokinetic-dilated HCM phenotype, while patients in N-ES showed hypokinetic-restrictive HCM phenotype. LGE extent was significantly larger in D-ES (34.7%?±?15.4% vs. 22.8%?±?7.7%; P?<?0.01). Atrial fibrillation and edema of lower extremity were more common in N-ES (72.7 vs. 29.3% and 54.5 vs. 24.4%, respectively; P?<?0.05). Log-rank test found no significant difference between 2 groups in combined end point of cardiovascular events (χ²?=?0.66, P?=?0.418). In multivariate analysis, LGE (HR 1.57–1.83 per 10% LGE increase, P?<?0.01) and indexed left atrial volume (LAVI) (HR 1.14–1.21 per 20 mL/m² increase, P?<?0.05) remained independently associated with combined end point when adjusted by other risk factors. The CMR features of HCM in end-stage span between two extremes. LGE is more extensive in those with ventricular remodeling and LAVI is larger in those with normal ventricular size. Both LGE and LAVI are significant predictors of poor outcomes.     

Cardiac function in patients with polymyositis or dermatomyositis: a three-dimensional speckle-tracking echocardiography study

Cardiac event is a major cause of death in patients with idiopathic inflammatory myopathies (IIM). The most frequent IIMs are polymyositis (PM) and dermatomyositis (DM). The purpose of this study was to analyze cardiac involvement by three-dimensional speckle-tracking echocardiography (3D STE) in patients with PM or DM, and to identify the relationship of cardiac injury with clinical characteristics and disease-specific parameters. 60 PM/DM patients with preserved left ventricular ejection fraction and 30 matched healthy controls were assessed by conventional echocardiography, 3D STE with biventricular strain analysis and electrocardiogram. Compared to controls, patients with PM/DM had significantly diminished left ventricular global longitudinal systolic strain and right ventricular longitudinal systolic strain (LVGLS, ? 20.3?±?2.5 vs. ? 23.4?±?1.7%; RVLS, ? 19.4?±?4.2 vs ? 24.8?±?2.0%; both P?<?0.001), and longer QTc intervals(421.0?±?38.4 vs 400.6?±?14.5 ms, P?=?0.001). Multiple regression analysis showed that Myositis Damage Index (MDI) was independently associated with LVGLS (R²?=?0.44, P?=?0.002) and RVLS (R²?=?0.56, P?<?0.001) in PM/DM patients with established disease course more than 1 year. In multivariate analysis of pooled data for all the PM/DM patients, when MDI was excluded due to missing observations, disease duration correlated with worse LVGLS (R²?=?0.24, P?=?0.002), while concomitant interstitial lung disease correlated with worse RVLS (R²?=?0.30, P?<?0.001). Disease activity scores (Myositis Intention to Treat Activities Index) had a weak positive correlation with QTc intervals (r_sp = 0.31, P?=?0.02). Our results suggest that cardiac injury in PM/DM is a long-term process and its severity depends on patients’ heterogeneous clinical features and systemic disease burden.     

Effect of cardiac resynchronization therapy on mitral valve geometry: a novel aspect as &quot;reversed mitral remodeling&quot;

Amelioration of the valvular geometry is a possible mechanism for mitral regurgitation (MR) improvement in patients receiving cardiac resynchronization therapy (CRT). We aimed to establish the precise definition, incidence, and predictors of reversed mitral remodeling (RMR), as well as the association with MR improvement and short-term CRT outcome. Ninety-five CRT recipients were retrospectively evaluated for the end-point of “MR response” defined as the absolute reduction in regurgitant volume (RegV) at 6 months. To identify RMR, changes in mitral deformation indices were tested for correlation with MR response and further analyzed for functional and echocardiographic CRT outcomes. Overall, MR response was observed in 50 patients (53%). Among the echocardiographic indices, the change in tenting area (TA) had the highest correlation with the change in RegV (r?=?0.653, p?<?0.001). The mean TA significantly decreased in MR responders (4.15?±?1.05 to 3.67?±?1.01 cm² at 6 months, p?<?0.001) and increased in non-responders (3.68?±?1.04 to 3.98?±?0.97 cm², p?=?0.014). The absolute TA reduction was used to identify patients with RMR (47%) which was found to be associated with higher rates of functional improvement (p?=?0.03) and volumetric CRT response (p?=?0.036) compared to those without RMR. Non-ischemic etiology and the presence of LBBB independently predicted RMR at multivariate analysis. In conclusion, reduction in TA is a reliable index of RMR, which relates to MR response, and functional and echocardiographic improvement with CRT. LBBB and non-ischemic etiology are independent predictors of RMR.     

Quantification of left atrial strain and strain rate using Cardiovascular Magnetic Resonance myocardial feature tracking: a feasibility study

Background

Cardiovascular Magnetic Resonance myocardial feature tracking (CMR-FT) is a quantitative technique tracking tissue voxel motion on standard steady-state free precession (SSFP) cine images to assess ventricular myocardial deformation. The importance of left atrial (LA) deformation assessment is increasingly recognized and can be assessed with echocardiographic speckle tracking. However atrial deformation quantification has never previously been demonstrated with CMR. We sought to determine the feasibility and reproducibility of CMR-FT for quantitative derivation of LA strain and strain rate (SR) myocardial mechanics.

Methods

10 healthy volunteers, 10 patients with hypertrophic cardiomyopathy (HCM) and 10 patients with heart failure and preserved ejection fraction (HFpEF) were studied at 1.5 Tesla. LA longitudinal strain and SR parameters were derived from SSFP cine images using dedicated CMR-FT software (2D CPA MR, TomTec, Germany). LA performance was analyzed using 4- and 2-chamber views including LA reservoir function (total strain [?_s], peak positive SR [SRs]), LA conduit function (passive strain [?_e], peak early negative SR [SRe]) and LA booster pump function (active strain [?_a], late peak negative SR [SRa]).

Results

In all subjects LA strain and SR parameters could be derived from SSFP images. There was impaired LA reservoir function in HCM and HFpEF (?_s [%]: HCM 22.1?±?5.5, HFpEF 16.3?±?5.8, Controls 29.1?±?5.3, p?<?0.01; SRs [s^?1]: HCM 0.9?±?0.2, HFpEF 0.8?±?0.3, Controls 1.1?±?0.2, p?<?0.05) and impaired LA conduit function as compared to healthy controls (?_e [%]: HCM 10.4?±?3.9, HFpEF 11.9?±?4.0, Controls 21.3?±?5.1, p?<?0.001; SRe [s^?1]: HCM ?0.5?±?0.2, HFpEF ?0.6?±?0.1, Controls ?1.0?±?0.3, p?<?0.01). LA booster pump function was increased in HCM while decreased in HFpEF (?_a [%]: HCM 11.7?±?4.0, HFpEF 4.5?±?2.9, Controls 7.8?±?2.5, p?<?0.01; SRa [s^?1]: HCM ?1.2?±?0.4, HFpEF ?0.5?±?0.2, Controls ?0.9?±?0.3, p?<?0.01). Observer variability was excellent for all strain and SR parameters on an intra- and inter-observer level as determined by Bland-Altman, coefficient of variation and intraclass correlation coefficient analyses.

Conclusions

CMR-FT based atrial performance analysis reliably quantifies LA longitudinal strain and SR from standard SSFP cine images and discriminates between patients with impaired left ventricular relaxation and healthy controls. CMR-FT derived atrial deformation quantification seems a promising novel approach for the study of atrial performance and physiology in health and disease states.     

Quantitative diffusion-weighted magnetic resonance imaging in the assessment of myocardial fibrosis in hypertrophic cardiomyopathy compared with T1 mapping

To identify myocardial fibrosis in hypertrophic cardiomyopathy (HCM) subjects using quantitative cardiac diffusion-weighted imaging (DWI) and to compare its performance with native T1 mapping and extracellular volume (ECV). Thirty-eight HCM subjects (mean age, 53?±?9 years) and 14 normal controls (mean age, 51?±?8 years) underwent cardiac magnetic resonance imaging (CMRI) on a 3.0T magnetic resonance (MR) machine with DWI, T1 mapping and late gadolinium enhancement (LGE) imaging as the reference standard. The mean apparent diffusion coefficient (ADC), native T1 value and ECV were determined for each subject. Overall, the HCM subjects exhibited an increased native T1 value (1241.04?±?78.50 ms), ECV (0.31?±?0.03) and ADC (2.36?±?0.34 s/mm²) compared with the normal controls (1114.60?±?37.99 ms, 0.24?±?0.04, and 1.62?±?0.38 s/mm², respectively) (p?<?0.05). DWI differentiated healthy and fibrotic myocardia with an area under the curve (AUC) of 0.93, while the AUCs of the native T1 values (0.93), (p?>?0.05) and ECV (0.94), (p?>?0.05) exhibited an equal differentiation ability. Both HCM LGE+ and HCM LGE? subjects had an increased native T1 value, ECV and ADC compared to the normal controls (p?<?0.05). HCM LGE+ subjects exhibited an increased ECV (0.31?±?0.04) and ADC (2.43?±?0.36 s/mm²) compared to HCM LGE? subjects (p?<?0.05). HCM LGE+ and HCM LGE? subjects had similar native T1 values (1250?±?76.36 ms vs. 1213.98?±?92.30 ms, respectively) (p?>?0.05). ADC values were linearly associated with increased ECV (R²?=?0.36) and native T1 values (R²?=?0.40) among all subjects. DWI is a feasible alternative to native T1 mapping and ECV for the identification of myocardial fibrosis in patients with HCM. DWI and ECV can quantitatively characterize the extent of fibrosis in HCM LGE+ and HCM LGE? patients.     

The effect of different treatment strategies on left ventricular myocardial deformation parameters in patients with chronic renal failure

The aim of this study was to compare left ventricular (LV) functions by speckle tracking echocardiography (STE) in chronic kidney disease (CKD) patients in various stages and under different renal replacement treatments in order to evaluate possible differences between them. This prospective study included 150 patients with CKD. Renal transplantation patients with glomerular filtration rate greater than 60 ml/min/1.73 m², patients receiving hemodialysis three times a week, and patients in the predialysis stage with glomerular filtration rate less than 30 ml/dk/1.73 m² were assigned into Group 1 (n?=?50), Group 2 (n?=?50), and Group 3 (n?=?50), respectively. LV longitudinal, circumferential, and radial myocardial deformation parameters (strain, strain rate [SR], rotation, twist) were evaluated by STE. Peak systolic longitudinal strain was higher in the transplantation group than the hemodialysis group (??19.93?±?3.50 vs???17.47?±?3.28%, p?<?0.017). Peak systolic circumferential strain was lower in the hemodialysis group (??20.97?±?4.90%) than Groups 1 and 3 (??25.87?±?4.20 and ??24.74?±?4.55%, respectively, p?<?0.001). Peak systolic radial SR was higher in the transplantation group than the hemodialysis group (1.84?±?0.52 vs 1.55?±?0.52 s^?1, respectively, p?<?0.017). Other longitudinal and circumferential deformation parameters together with peak early diastolic radial SR and twist were also significantly different between the groups. Strain, SR, and twist values were mostly lower in the hemodialysis patients, but generally higher in the transplantation patients. LV functions evaluated by STE are better in the renal transplantation patients than the hemodialysis patients and than those in the predialysis stage. This may indicate beneficial effects of renal transplantation on cardiac functions.     

Cardiac magnetic resonance and galectin-3 level as predictors of prognostic outcomes for non-ischemic cardiomyopathy patients

This study was aimed at determining whether late gadolinium enhancement (LGE) in conjunction with Galectin-3 (Gal-3) level offered more precise prognosis of non-ischemic cardiomyopathy (NICM) in comparison to LGE alone. Results of LGE and Gal-3 expression in 192 patients with NICM, including 85 subjects with dilated cardiomyopathy (DCM) and 107 with hypertrophic cardiomyopathy (HCM), were examined. As suggested by the characteristics of LGE and Gal-3 levels, patients were divided into four groups: LGE positive?+?low Gal-3 (n?=?10 for DCM, n?=?15 for HCM), LGE positive?+?high Gal-3 (n?=?25 for DCM, n?=?51 for HCM), LGE negative?+?low Gal-3 (n?=?32 for DCM, n?=?29 for HCM), LGE negative?+?high Gal-3 (n?=?18 for DCM, n?=?12 for HCM). Primary endpoints over the follow-up period included major adverse cardiac events (MACEs). Kaplan–Meier survival analysis and univariate Cox proportional hazard models were used to analyze the survival status of patients with NICM. The optimal cut-off value of Gal-3 level for two types of NICM was determined by receiver operating characteristic analysis (13.38 U/L for DCM and 14.40 U/L for HCM). The combination of LGE and Gal-3 levels offered a more significant prognostic value than using LGE alone for both DCM and HCM (DCM P?=?0.001?<?0.012; HCM P?=?0.037?<?0.040). Moreover, the Cox proportional hazard model suggested that both LGE status [Hazard ratio (HR)?=?2.62, P?=?0.017] and Gal-3 level (HR?=?1.16, P?=?0.013) were significant predictors of MACEs in DCM, while they did not appear to have significant prognostic values for HCM (P?=?0.06 and 0.64). Furthermore, the multivariate analysis only confirmed LGE as an independent element in predicting prognosis of DCM (HR?=?12.19, P?=?0.026). In conclusion, LGE status was an independent indicator of DCM prognosis, yet the insignificant role of LGE in HCM prognosis could be limited by sample size.     

Phenylephrine increases near-infrared spectroscopy determined muscle oxygenation in men

Phenylephrine increases mean arterial pressure (MAP) by enhanced total peripheral resistance (TPR) but near-infrared spectroscopy (NIRS) determined muscle oxygenation (S_mO₂) increases. We addressed that apparent paradox during supine rest and head-up tilt (HUT). Variables were determined?±?phenylephrine in males during supine rest (n?=?17) and 40° HUT (n?=?7). MAP, stroke volume (SV), heart rate (HR), and TPR were derived by Modelflow^® and NIRS determined biceps S_mO₂ and (tibial) bone oxygenation (S_tibialO₂). For ten subjects, cardiac filling and the diameter of the inferior caval vein (ICV collapsibility index: ((ICV_expiration???ICV_inspiration)/ICV_expiration)?×?100) were assessed by ultrasound. Pancreatic polypeptide (PP) and atrial natriuretic peptide (proANP) in plasma were determined by immunoassay. Brachial artery blood flow was assessed by ultrasound and skin oxygenation (S_skinO₂) monitored by white light spectroscopy. Phenylephrine increased MAP by 34% and TPR (62%; P?<?0.001) during supine rest. The ICV collapsibility index decreased (24%; P?<?0.001) indicating augmented cardiac preload although volume of the left atrium and ventricle did not change. SV increased (18%; P?<?0.001) as HR decreased (24%; P?<?0.001). ProANP increased by 9% (P?=?0.002) with unaffected PP. Brachial artery blood flow tended to decrease while S_skinO₂ together with S_tibialO₂ decreased by 11% (P?=?0.026) and 20% (P?<?0.001), respectively. Conversely, phenylephrine increased S_mO₂ (9%) and restored the HUT elicited decrease in S_mO₂ (by 19%) along with SV (P?=?0.02). Phenylephrine reduces skin and bone oxygenation and tends to reduce arm blood flow, suggesting that the increase in S_mO₂ reflects veno-constriction with consequent centralization of the blood volume.     

Coronary flow reserve in mitral stenosis before and after percutaneous balloon mitral valvuloplasty

We aimed to evaluate the coronary flow reserve (CFR) before and after percutaneous balloon mitral valvuloplasty (PBMV) in patients with mitral stenosis (MS) and its association to clinical events. A prospective study included 45 patients with mitral stenosis candidate for PBMV (age 38?±?19 years, 27 were females) and 20 with matched age and sex, healthy controls were included in the study. Noninvasive CFR was measured using transthoracic echocardiography and utilizing adenosine stress echocardiography (0.14 mg/kg/min) before PMBV, and one weak post PBMV using multi-tract balloon valvuloplasty technique. CFR was significantly lower in patients with MS compared to controls (P?<?0.001). Moreover the CFR was significantly increased post-PBMV (P?<?0.001) associated with significant increase in LVEF% (P?<?0.05), decrease in systolic pulmonary artery pressure (P?<?0.001), significant increase in TAPSE (P?<?0.001). CFR was significantly correlated with the degree of change (Δ) in MVA, TAPSE, LVEF%, mean mitral PG and sPAP (r?=?0.77, P?<?0.001, r?=?0.63; P?<?0.001; r?=?0.42; P?<?0.05; r?=??0.81; P?<?0.001 and r?=??0.65; P?<?0.001). Mitral valve stenosis was associated with significantly impaired coronary flow reserve that significantly improved after PMBV. The improved CFR values were significantly correlated with the gain in the MVA and the improvement in the functions of both left and right ventricles.     

Diffusion-weighted MRI and PET–CT in the follow up of chronic periaortitis

Aim of the present study is to compare magnetic resonance imaging (MRI) and positron emission tomography (PET) parameters in the follow up of chronic periaortitis (CP), with a focus on changes in the apparent diffusion coefficient (ADC) and standardized uptake values (SUV). 127 patients with CP were treated in our urology between 2007 and 2017. We identified 14 patients with parallel abdominal MRI and PET–CT examinations before therapy and in the follow up resulting in a total of 56 examinations. Relative contrast uptake and diffusion-weighted MRI parameters were compared to SUV in the corresponding PET–CT examinationsand laboratory infection markers. All examined MRI and PET–CT parameters showed significant changes between basis and follow-up examinations. Median ADC values increased significantly (p?<?0.001) in the follow up. SUVmax and the other MR parameter (contrast uptake, DWI-signal) declined significantly. We observed a strong negative correlation between ADC and SUVmax (rho: ??0.61; p?<?0.001). In addition, we found an inverse correlation of ADC with the inflammation markers ESR (rho: ??0.64; p?<?0.001) and CRP (rho: ??0.54; p?=?0.001). MRI and PET–CT showed comparable results in the individual follow up of CP and compared to laboratory inflammation markers. Our data support MRI as first imaging modality due to absent radiation and the necessity of repetitive follow-up examinations in patients with CP.     

Left Atrial structure and function in hypertrophic cardiomyopathy sarcomere mutation carriers with and without left ventricular hypertrophy

Background

Impaired left atrial (LA) function is an early marker of cardiac dysfunction and predictor of adverse cardiac events. Herein, we assess LA structure and function in hypertrophy in hypertrophic cardiomyopathy (HCM) sarcomere mutation carriers with and without left ventricular hypertrophy (LVH).

Method

Seventy-three participants of the HCMNet study who underwent cardiovascular magnetic resonance (CMR) imaging were studied, including mutation carriers with overt HCM (n =?34), preclinical mutation carriers without HCM (n =?24) and healthy, familial controls (n =?15).

Results

LA volumes were similar between preclinical, control and overt HCM cohorts after covariate adjustment. However, there was evidence of impaired LA function with decreased LA total emptying function in both preclinical (64?±?8%) and overt HCM (59?±?10%), compared with controls (70?±?7%; p =?0.002 and p =?0.005, respectively). LA passive emptying function was also decreased in overt HCM (35?±?11%) compared with controls (47?±?10%; p =?0.006). Both LAtotal emptying function and LA passive emptying function were inversely correlated with the extent of late gadolinium enhancement (LGE; p?=?0.005 and p <?0.05, respectively), LV mass (p =?0.02 and p <?0.001) and interventricular septal thickness (p?<?0.001 for both) and serum NT-proBNP levels (p?<?0.001 for both).

Conclusion

LA dysfunction is detectable by CMR in preclinical HCM mutation carriers despite non-distinguishable LV wall thickness and LA volume. LA function appears most impaired in subjects with overt HCM and a greater extent of LV fibrosis.

     

Intramyocardial dissecting hematoma in anterior wall ST elevation myocardial infarction: impact on left ventricular remodeling and prognosis

Intramyocardial dissecting hematoma is an uncommon complication of myocardial infarction potentially leading to cardiac rupture. The aim of the present study was to investigate coronary reperfusion results, left ventricular (LV) function recovery and remodeling and clinical outcomes in patients with anterior STEMI complicated by intramyocardial hematoma. We prospectively studied 87 patients (mean age 59?±?10 years; 88% male) with anterior STEMI (42 with intramyocardial hematoma) in order to evaluate coronary reperfusion results, LV remodeling (≥15% increase in end-systolic volume) and clinical outcomes (cardiac death, non-fatal reinfarction, and hospitalization for congestive heart failure) at 24 months. Thrombolysis in myocardial infarction (TIMI) flow score and myocardial blush grade (MBG) were assessed both pre- and post-percutaneous coronary intervention (PCI) and speckle-tracking echocardiography was performed post PCI and at 6-month follow-up. Patients with hematoma had lower post-PCI TIMI score and MBG, higher heart rate, worse LV ejection fraction and longitudinal or rotational function than their counterparts. LV remodeling occurred in 33 (78.6%) patients with hematoma and 11 (24.4%) patients without (p?<?0.001). Independent predictors of LV remodeling were heart rate (p?=?0.018), MBG (p?=?0.036) and presence of hematoma (p?<?0.001). Hematoma (log-rank test, χ²?=?9.849; p?=?0.002) and LV remodeling (log-rank test, χ²?=?13.770; p?<?0.001) were associated to a higher rate of adverse events. Cox analysis identified LV remodeling as the only independent predictor of adverse events (hazard ratio?=?3.912; 95% confidence interval, 1.429–10.714; p?=?0.008). Intramyocardial dissecting hematoma complicating anterior STEMI is an independent determinant of LV remodeling and is associated to poor prognosis.     

Left atrial strain rate during atrial contraction predicts raised pulmonary capillary wedge pressure: evidence for left atrio-ventricular interaction

This study aimed to assess the relationship between different LA strain components and PCWP as well as to the relationship with other established methods. We studied 144 symptomatic patients, age 63?±?14 years, 54 males, using conventional transthoracic echocardiography protocols, including LA and LV myocardial deformation from speckle tracking technique investigations along with simultaneous right heart catheterization (RHC) using established techniques. From RHC, pulmonary artery pressure (PAP), and pulmonary capillary wedge pressure (PCWP) were measured and pulmonary vascular resistance (PVR) calculated. LA strain rate during atrial contraction (LASRa) was the strongest correlate with PCWP (r²?=????0.40, p?<?0.001), over and above both LASR during LV systole (LASRs) and LA longitudinal strain during ventricular systole (LASs) (r²?=?0.21 and 0.19, respectively, p?<?0.001 for both). The correlation between LASRa and PCWP was stronger in patients with post-capillary PH compared to pre-capillary PH (r²?=?0.21 vs. r²?=?0.02, respectively). The strongest relationship between LASRa and PCWP was in patients with enlarged LA volume?>?34 ml/m² (r²?=?0.60, p?<?0.001). In all patients LASRa?<??=?0.9 1/s was 88% accurate in predicting LA pressure?>?15 mmHg which was superior to recently proposed uni- and multi-variable models. LASR during atrial contraction is the strongest predictor of PCWP, particularly in patients with post-capillary PH and with dilated LA cavity. Furthermore, it proved superior to recently proposed uni- and multi-variable based algorithms. Its close relationship with LV strain rate counterpart reflects important left heart chamber interaction in patients with raised LA pressure.

     

Evaluation of Clostridium difficile Infection with PET/CT Imaging in a Mouse Model

Purpose

Existing clinical or microbiological scores are not sensitive enough to obtain prompt identification of patients at risk of complicated Clostridium difficile infection (CDI). Our aim was to use a CDI animal model to evaluate 2-deoxy-2-[¹⁸F]fluoro-D-glucose positron emission tomography ([¹⁸F]FDG-PET) as a marker of severe course of infection.

Procedures

CDI was induced with cefoperazone for 10 days followed by clindamycin 1 day before C. difficile inoculation. Mice were divided into wild type (n?=?6), antibiotic without infection (AC n?=?4), h001-infected (n?=?5, ribotype 001), and h027-infected (n?=?5, ribotype 027). Two days after inoculation, [¹⁸F]FDG-PET was acquired. Weight, general animal condition, and survival were monitored daily for 9 days.

Results

h001 group showed symptoms for 4 days with 0 % mortality and a similar colon uptake than control animals (h001 0.52?±?0.20, WT 0.42?±?0.07, and AC 0.36?±?0.06). The h027 group showed symptoms up to 7 days, with 66.7 % of mortality 4 days after infection, and significantly higher colon uptake (0.93?±?0.38, p?<?0.05). Clinical score was associated to colon and cecum uptake (rho?=?0.78, p?=?0.0001) (rho?=?0.73, p?=?0.0003).

Conclusion

High toxin producer ribotype 027 induced more severe CDI infections, correlating with higher colon and cecum [¹⁸F]FDG uptake. Colon uptake may purportedly serve as early predictor of CDI severity.

     

Experimental comparison of performances of Mega Acer Kit,Ranger and ThermoSens according to flow rates and distances

We experimentally investigated the fluid warming performances of three warmers with different technology, according to flow rates and distances. We used the following intravenous fluid warmers: Mega Acer Kit (Group M, n?=?8), Ranger (group R, n?=?8), and ThermoSens (group T, n?=?8). Fluids that had been stored in the operating room over the previous 24 h were delivered at sequent flow rates of from 440 mL/h up to 2500 mL/h through preheated warming devices. The fluid temperatures were recorded at the inlet point, 76-cm proximal (P_out1) and 166-cm distal outlet points (P_out2) every 1 min for 10 min. We repeated each test eight times. The delivered fluid temperature [mean (95% confidence interval)] was significantly higher in group M than group R and T at flow rates up to 650 mL/h with the highest value at 440 mL/h [34.30 (33.35–35.24)°C] (P?<?0.001), and was higher in group T and R at flow rates over 1140 mL/h at P_out1 [36.67 (36.62–36.73)°C and 37.85 (37.52–38.17)°C at 2500 mL/h, respectively] (P?<?0.001). It was significantly higher at the P_out1 than the P_out2 at all flow rates for each device (P?<?0.001). Mega Acer Kit can warm fluid more effectively compared with ThermoSens and Ranger at the low flow rate whereas the ThermoSens and the Ranger are suitable at higher flow rates. Furthermore, the device performance is more effective with shorter extension lines.     

Contribution of mitral valve leaflet length and septal wall thickness to outflow tract obstruction in patients with hypertrophic cardiomyopathy

We sought to examine whether elongation of the mitral valve leaflets in patients with hypertrophic cardiomyopathy (HCM) is synergistic to septal wall thickness (SWT) in the development of left ventricular outflow tract obstruction (LVOTO). HCM is a common genetic cardiac disease characterized by asymmetric septal hypertrophy and predisposition towards LVOTO. It has been reported that elongation of the mitral valve leaflets may be a primary phenotypic feature and contribute to LVOTO. However, the relative contribution of this finding versus SWT has not been studied. 152 patients (76 with HCM and 76 non-diseased age, race and BSA-matched controls) and 18 young, healthy volunteers were studied. SWT and the anterior mitral valve leaflet length (AMVLL) were measured using cine MRI. The combined contribution of these variables (SWT × AMVLL) was described as the Septal Anterior Leaflet Product (SALP). Peak LVOT pressure gradient was determined by Doppler interrogation and defined as “obstructive” if?≥?30 mmHg. Patients with HCM were confirmed to have increased AMVLL compared with controls and volunteers (p?<?0.01). Among HCM patients, both SWT and SALP were significantly higher in patients with LVOTO (N?=?17) versus without. SALP showed modest improvement in predictive accuracy for LVOTO (AUC?=?0.81) among the HCM population versus SWT alone (AUC?=?0.77). However, in isolated patients this variable identified patients with LVOTO despite modest SWT. Elongation of the AMVLL is a primary phenotypic feature of HCM. While incremental contributions to LVOTO appear modest at a population level, specific patients may have dominant contribution to LVOTO. The combined marker of SALP allows for maintained identification of such patients despite modest increases in SWT.