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1.
Int J Cardiol Heart Vasc ; 45: 101190, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36941997

RESUMEN

Background: Percutaneous mitral valve repair (PMVR) has evolved to be a standard procedure in suitable patients with mitral regurgitation (MR) not accessible for open surgery. Here, we analyzed the influence of the number and positioning of the clips implanted during the procedure on MR reduction analyzing also sub-collectives of functional and degenerative MR (DMR). Results: We included 410 patients with severe MR undergoing PMVR using the MitraClip® System. MR and reduction of MR were analyzed by TEE at the beginning and at the end of the PMVR procedure. To specify the clip localization, we sub-divided segment 2 into 3 sub-segments using the segmental classification of the mitral valve. Results: We found an enhanced reduction of MR predominantly in DMR patients who received more than one clip. Implantation of only one clip led to a higher MR reduction in patients with functional MR (FMR) in comparison to patients with DMR. No significant differences concerning pressure gradients could be observed in degenerative MR patients regardless of the number of clips implanted. A deterioration of half a grade of the achieved MR reduction was observed 6 months post-PMVR independent of the number of implanted clips with a better stability in FMR patients, who got 3 clips compared to patients with only one clip. Conclusions: In patients with FMR, after 6 months the reduction of MR was more stable with an increased number of implanted clips, which suggests that this specific patient collective may benefit from a higher number of clips.

2.
JACC Basic Transl Sci ; 8(1): 37-50, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36777171

RESUMEN

MIRTH (Myocardial Intramural Remodeling by Transvenous Tether) is a transcatheter ventricular remodeling procedure. A transvenous tension element is placed within the walls of the beating left ventricle and shortened to narrow chamber dimensions. MIRTH uses 2 new techniques: controlled intramyocardial guidewire navigation and EDEN (Electrocardiographic Radial Depth Navigation). MIRTH caused a sustained reduction in chamber dimensions in healthy swine. Midventricular implants approximated papillary muscles. MIRTH shortening improved myocardial contractility in cardiomyopathy in a dose-dependent manner up to a threshold beyond which additional shortening reduced performance. MIRTH may help treat dilated cardiomyopathy. Clinical investigation is warranted.

3.
JACC Case Rep ; 4(17): 1104-1109, 2022 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-36124158

RESUMEN

Extreme endurance athletic challenges provide unique opportunities to study the cardiovascular system's capacity for structural, functional, and hemodynamic adaptation. The authors present a case of a male subject who ran 2,469 km, with serial multiparametric cardiac magnetic resonance imaging used to demonstrate adaptive and maladaptive alterations in cardiac remodeling and myocardial tissue health. (Level of Difficulty: Advanced.).

4.
JACC Basic Transl Sci ; 7(5): 465-483, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35663630

RESUMEN

Heart failure (HF) is characterized by progressive fibrosis. Both fibroblasts and mesenchymal stem cells (MSCs) can differentiate into pro-fibrotic myofibroblasts. MSCs secrete and express platelet-derived growth factor (PDGF) and its receptors. We hypothesized that PDGF signaling in cardiac MSCs (cMSCs) promotes their myofibroblast differentiation and aggravates post-myocardial infarction left ventricular remodeling and fibrosis. We show that cMSCs from failing hearts post-myocardial infarction exhibit an altered phenotype. Inhibition of PDGF signaling in vitro inhibited cMSC-myofibroblast differentiation, whereas in vivo inhibition during established ischemic HF alleviated left ventricular remodeling and function, and decreased myocardial fibrosis, hypertrophy, and inflammation. Modulating cMSC PDGF receptor expression may thus represent a novel approach to limit pathologic cardiac fibrosis in HF.

5.
Eur J Radiol Open ; 9: 100404, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35265735

RESUMEN

Objectives: Quantitative evaluations of function, volume and mass are fundamental in the diagnostic workup of different cardiovascular diseases and can be exactly determined by CMRI in sinus rhythm. This does not hold true in arrhythmia as CMR is hampered by reconstruction artifacts caused by inconsistent data from multiple heartbeats. Real-time (RT) MRI at high temporal resolution might reduce these problems. Methods: Consecutive patients with atrial fibrillation were prospectively included and underwent RT and conventional CINE CMR in randomized order. 29 patients were studied at 1.5 T and 30 patients at 3 T. At 3 T a group of 20 subjects in sinus rhythm served as controls. RT and CINE image quality was evaluated in different planes and for different wall sections using a Likert scale (from zero to four). Volumetric analysis was performed using two types of software and differences between RT and CINE CMR were evaluated. Results: In patients with atrial fibrillation RT CMR short axis (SA) resulted in a significantly higher image quality compared to CINE imaging both at 1.5 T and 3 T (1.5 T: mid SA: 3.55 ± 0.5 RT vs 2.6 ± 0.9 CINE, p = 0.0001; 3 T: mid SA: 3.15 ± 0.9 RT vs 2.6 ±1.0 CINE, p = 0.03); This qualitative difference was more marked and significant for the long axis views (2CV and 4CV) at 1.5 T (1.5 T: 2CV: 3.2 ± 0.6 RT vs 2.65 ± 1.1 CINE; p = 0.011; 4CV: 2.9 ± 0.69 RT vs 2.4 ± 0.9 CINE; p = 0.0044). During sinus rhythm CINE images were superior concerning diagnostic quality (3 T mid SA: 3.35 ± 0.45 RT vs 3.8 ± 0.5 CINE, p = 0.008). Quantitative analysis was successful with both software packages and the results showed a good correlation (Pearson correlation between 0.679 and 0.921 for patients). RT CMR resulted in slightly lower functional volumes than CINE CMR (3 T: patients: EDVI 86 ± 29 ml/m2 RT vs 93 29 ml/m2± 29 CINE, Pearson r = 0.902) but similar ejection fractions (3 T: patients: EF 47 ± 16% RT vs 45 ± 13% CINE, Pearson r = 0679; controls: EF 63 ± 6 RT vs 63 ± 3 CINE, Pearson r = 0.695). Conclusion: RT CMR improves image quality in arrhythmic patients and renders studies more comfortable. Volumetric analysis is feasible with slightly lower values relative to CINE CMR, while ejection fractions are comparable.

6.
Int J Cardiol Heart Vasc ; 37: 100884, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34660881

RESUMEN

BACKGROUND: Electrocardiogram (ECG) measured QRS duration has been shown to influence cardiovascular outcomes. However, there is paucity of data on whether ECG QRS duration is influenced by obesity and sex in large populations. METHODS: All ECGs performed by a pathology provider over a 2-year period were included. ECGs with confounding factors and those not in sinus rhythm were excluded from the primary analysis. RESULTS: Of the 76,220 who met the inclusion criteria, 41,685 (55%) were females. The median age of the study cohort was 61 years (interquartile [IQR] range 48-71 years). The median QRS duration was 86 ms (IQR 80-94 ms). The median BMI was 27.6 kg/m2 (IQR 24.2-31.8 kg/m2). When stratified according to the World Health Organization classification of BMI < 18.50 kg/m2, 18.50-24.99 kg/m2, 25.00-29.99 kg/m2, and ≥ 30.00 kg/m2, the median QRS durations were 82 ms (IQR 76-88 ms), 86 ms (IQR 80-92 ms), 88 ms (IQR 80-94 ms) and 88 ms (IQR 82-94 ms), respectively (p < 0.001 for linear trend). Median QRS duration for females was 84 ms (IQR 78-88 ms); for males, it was 92 ms (IQR 86-98 ms), p < 0.001. Compared to males, females had narrower QRS complexes at similar age and similar BMI. In multiple linear regression analysis, BMI correlated positively with QRS duration (standardized beta 0.095, p < 0.001) independent of age, sex, and heart rate. CONCLUSIONS: In this large cohort there was a positive association between increasing BMI and QRS duration. Females had narrower QRS duration than males at similar age and similar BMI.

7.
Int J Cardiol Hypertens ; 9: 100083, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34095810

RESUMEN

BACKGROUND: Heterozygous familial hypercholesterolemia (heFH) is a genetic disorder leading to premature coronary artery disease (CAD). We hypothesized that the subclinical pathophysiologic consequences of hypercholesterolemia may be detected before the occurrence of clinically overt CAD by stress testing and myocardial strain imaging. PATIENTS-METHODS: We evaluated the treadmill tests (ETTs) of 46 heFH men without known arterial hypertension/diabetes mellitus/vasculopathy like CAD and of 39 healthy men matched for age, baseline systolic/diastolic blood pressure (BP) and heart rate (HR), using Bruce protocol. Global longitudinal strain (GLS) of the left ventricle (LV) additionally to ejection fraction was obtained. RESULTS: heFH men reached a significantly higher peak systolic and diastolic BP compared to controls (p = 0.002 and p < 0.001, respectively). Mean rate pressure product was significantly higher in heFH patients (p = 0.038). Both duration of the ETT and workload in metabolic equivalents was lower in the heFH group (p < 0.001 and p < 0.001, respectively). Baseline to peak rise of systolic and diastolic BP in heFH men was higher (p = 0.008 and p < 0.001 for systolic and diastolic BP, respectively). Furthermore, heFH men had higher rise of HR from baseline to peak, compared to controls; (p = 0.047). GLS in heHF men was slightly decreased (p = 0.014), although the ejection fraction was similar in both groups. CONCLUSION: heFH men have a higher rise in systolic/diastolic BP during ETT, which may reflect early, preclinical hypertension. Furthermore, slight impairment of LV GLS is present, despite the absence of apparent myocardial dysfunction in conventional 2D echocardiography.

8.
JACC Basic Transl Sci ; 6(4): 350-361, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33997521

RESUMEN

A first-in-man clinical study on a myocardial-derived decellularized extracellular matrix hydrogel suggested the potential for efficacy in chronic myocardial infarction (MI) patients. However, little is understood about the mechanism of action in chronic MI. In this study, the authors investigated the efficacy and mechanism by which the myocardial matrix hydrogel can mitigate negative left ventricular (LV) remodeling in a rat chronic MI model. Assessment of cardiac function via magnetic resonance imaging demonstrated preservation of LV volumes and apical wall thickening. Differential gene expression analyses showed the matrix is able to prevent further negative LV remodeling in the chronic MI model through modulation of the immune response, down-regulation of pathways involved in heart failure progression and fibrosis, and up-regulation of genes important for cardiac muscle contraction.

9.
JACC Cardiovasc Imaging ; 13(11): 2330-2339, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32763118

RESUMEN

Objectives: This study evaluated cardiac involvement in patients recovered from coronavirus disease-2019 (COVID-19) using cardiac magnetic resonance (CMR). Background: Myocardial injury caused by COVID-19 was previously reported in hospitalized patients. It is unknown if there is sustained cardiac involvement after patients' recovery from COVID-19. Methods: Twenty-six patients recovered from COVID-19 who reported cardiac symptoms and underwent CMR examinations were retrospectively included. CMR protocols consisted of conventional sequences (cine, T2-weighted imaging, and late gadolinium enhancement [LGE]) and quantitative mapping sequences (T1, T2, and extracellular volume [ECV] mapping). Edema ratio and LGE were assessed in post-COVID-19 patients. Cardiac function, native T1/T2, and ECV were quantitatively evaluated and compared with controls. Results: Fifteen patients (58%) had abnormal CMR findings on conventional CMR sequences: myocardial edema was found in 14 (54%) patients and LGE was found in 8 (31%) patients. Decreased right ventricle functional parameters including ejection fraction, cardiac index, and stroke volume/body surface area were found in patients with positive conventional CMR findings. Using quantitative mapping, global native T1, T2, and ECV were all found to be significantly elevated in patients with positive conventional CMR findings, compared with patients without positive findings and controls (median [interquartile range]: native T1 1,271 ms [1,243 to 1,298 ms] vs. 1,237 ms [1,216 to 1,262 ms] vs. 1,224 ms [1,217 to 1,245 ms]; mean ± SD: T2 42.7 ± 3.1 ms vs. 38.1 ms ± 2.4 vs. 39.1 ms ± 3.1; median [interquartile range]: 28.2% [24.8% to 36.2%] vs. 24.8% [23.1% to 25.4%] vs. 23.7% [22.2% to 25.2%]; p = 0.002; p < 0.001, and p = 0.002, respectively). Conclusions: Cardiac involvement was found in a proportion of patients recovered from COVID-19. CMR manifestation included myocardial edema, fibrosis, and impaired right ventricle function. Attention should be paid to the possible myocardial involvement in patients recovered from COVID-19 with cardiac symptoms.


Asunto(s)
Infecciones por Coronavirus/terapia , Edema Cardíaco/diagnóstico por imagen , Imagen por Resonancia Cinemagnética , Neumonía Viral/terapia , Disfunción Ventricular Derecha/diagnóstico por imagen , Adulto , COVID-19 , China , Infecciones por Coronavirus/complicaciones , Infecciones por Coronavirus/diagnóstico , Edema Cardíaco/etiología , Edema Cardíaco/patología , Femenino , Fibrosis , Humanos , Masculino , Persona de Mediana Edad , Miocardio/patología , Pandemias , Neumonía Viral/complicaciones , Neumonía Viral/diagnóstico , Valor Predictivo de las Pruebas , Inducción de Remisión , Estudios Retrospectivos , Disfunción Ventricular Derecha/etiología , Disfunción Ventricular Derecha/fisiopatología , Función Ventricular Derecha
10.
JACC Basic Transl Sci ; 5(6): 561-578, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32613144

RESUMEN

Heart failure is an important, and growing, cause of morbidity and mortality. Half of patients with heart failure have preserved ejection fraction, for whom therapeutic options are limited. Here we report that cardiac bridging integrator 1 gene therapy to maintain subcellular membrane compartments within cardiomyocytes can stabilize intracellular distribution of calcium-handling machinery, preserving diastolic function in hearts stressed by chronic beta agonist stimulation and pressure overload. This study identifies that maintenance of intracellular architecture and, in particular, membrane microdomains at t-tubules, is important in the setting of sympathetic stress. Stabilization of membrane microdomains may be a pathway for future therapeutic development.

11.
JACC Basic Transl Sci ; 5(5): 463-480, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32478208

RESUMEN

This study assessed the regional changes in myocardial geometry, microstructure, mechanical behavior, and properties that occur in response to progressive left ventricular pressure overload (LVPO) in a large animal model. Using an index of local biomechanical function at early onset of LVPO allowed for prediction of the magnitude of left ventricular chamber stiffness (Kc) and left atrial area at LVPO late timepoints. Our study found that LV myocardial collagen content alone was insufficient to identify mechanisms for LV myocardial stiffness with progression to heart failure with preserved ejection fraction (HFpEF). Serial assessment of regional biomechanical function might hold value in monitoring the natural history and progression of HFpEF, which would allow evaluation of novel therapeutic approaches.

12.
JACC Basic Transl Sci ; 5(12): 1228-1239, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33426378

RESUMEN

Phosphorylcholine monoclonal immunoglobulin G antibody attenuates the immediate post-ischemic inflammatory response by reducing the proinflammatory chemokine (C-C motif) ligand 2 chemokine and circulating Ly-6Chi monocytes. This subsequently enhances the post-ischemic repair process, resulting in limited adverse cardiac remodeling and preservation of cardiac function. Therefore, phosphorylcholine monoclonal immunoglobulin G antibody therapy may be a valid therapeutic approach against myocardial ischemia-reperfusion injury.

13.
Int J Cardiol Heart Vasc ; 24: 100413, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31508480

RESUMEN

INTRODUCTION: In this study, we evaluated right ventricular (RV) function before and after percutaneous mitral valve repair (PMVR) using conventional echocardiographic parameters and novel 3DE data sets acquired prior to and directly after the procedure. PATIENTS AND METHODS: Observational study on 45 patients undergoing PMVR at an university hospital. RESULTS: In the overall collective, the 3D RV-EF before and after PMVR showed no significant change (p = 0.16). While there was a significant increase of the fractional area change (FAC, from 23 [19-29] % to 28 [24-33] %, p = 0.001), no significant change of the tricuspid annular plane systolic excursion (TAPSE, from 17 ±â€¯6 mm to 18 ±â€¯5 mm (standard deviation), p = 0.33) was observed. Regarding patients with a reduced RV-EF (< 35%), a significant RV-EF improvement was observed (from 27 [23-34] % to 32.5 [30-39] % (p = 0.001). 71.4% of patients had an improved clinical outcome (improvement in 6-minute walk test and/or improvement in NYHA class of more than one grade), whereas clinical outcome did not improve in 28.6% of patients. Using univariate logistic regression analysis, the post-PMVR RV-EF (OR 1.15: 95% CI 1.02-1.29; p = 0.02) and the change in RV-EF (OR 1.13: 95% CI 1.02-1.25; p = 0.02) were significant predictors for improved clinical outcome at 6 months follow up. CONCLUSION: Thus, RV function may be an important non-invasive parameter to add to the predictive parameters indicating a potential clinical benefit from treatment of severe mitral regurgitation using PMVR.

14.
JACC Basic Transl Sci ; 2(5): 529-542, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30062169

RESUMEN

This study investigated the release and proteomic profile of tissue factor microparticles (TFMPs) prospectively (up to 6 months) following a myocardial infarction (MI) in a chronic porcine model to establish their utility in tracking cellular level activities that predict physiologic outcomes. Our animal groups (n = 6 to 8 each) consisted of control, noninfarcted (negative control); infarcted only (positive control); and infarcted animals treated with cardiac resynchronization therapy (CRT) and a ß-blocker (BB) (metoprolol succinate). The authors found different protein profiles in TFMPs between the control, infarcted only group, and the CRT + BB treated group with predictive impact on the outward phenotype of pathological remodeling after an MI within and between groups. This novel approach of monitoring cellular level activities by profiling the content of TFMPs has the potential of addressing a shortfall of the current crop of cardiac biomarkers, which is the inability to capture composite molecular changes associated with chronic maladaptive signaling in a spatial and temporal manner.

15.
JACC Basic Transl Sci ; 2(6): 669-683, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30062182

RESUMEN

Inotropic support is often required to stabilize the hemodynamics of patients with acute decompensated heart failure; while efficacious, it has a history of leading to lethal arrhythmias and/or exacerbating contractile and energetic insufficiencies. Novel therapeutics that can improve contractility independent of beta-adrenergic and protein kinase A-regulated signaling, should be therapeutically beneficial. This study demonstrates that acute protein kinase C-α/ß inhibition, with ruboxistaurin at 3 months' post-myocardial infarction, significantly increases contractility and reduces the end-diastolic/end-systolic volumes, documenting beneficial remodeling. These data suggest that ruboxistaurin represents a potential novel therapeutic for heart failure patients, as a moderate inotrope or therapeutic, which leads to beneficial ventricular remodeling.

16.
Egypt Heart J ; 69(2): 95-101, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29622962

RESUMEN

BACKGROUND: Significant coronary artery stenosis might cause persistently impaired longitudinal left ventricle (LV) function at rest. LV global longitudinal strain (LVGLS) can be accurately assessed by 2D speckle-tracking strain echocardiography(2D-STE). OBJECTIVE: We aimed to evaluate the diagnostic accuracy of LV global longitudinal strain obtained by 2D-STE in prediction of severity of CAD. METHODS: Eighty patients with suspected stable angina pectoris were included. They underwent transthoracic echocardiography (TTE) to measure LV ejection fraction, 2-D-STE to measure GLS and coronary angiography (CA). The patients were divided into two groups: group 1 (58 patients) with significant (>70%) CAD, and group 2 (22 patients) with non-significant (<70%) CAD. Images were obtained in the apical long-axis, four-chamber, and two chamber views. Regional longitudinal systolic strain was measured in 17 myocardial segments and averaged to provide global longitudinal strain (LVGLS). RESULTS: There was significant decrease in GLS in group 1 compared to group 2 (-11.86 ± 2.89% versus -18.65 ± 0.79%, P < 0.000). The optimal cutoff value of GLS for prediction of significant CAD was -15.6% [AUC 0.88, 95% CI 0.78-0.96 p < 0.000]. The sensitivity, specificity and accuracy of GLS for detecting significant CAD were 93.1%, 81.8%,and 90% respectively.There was a significant positive correlation between GLS and EF (r = 0.33; p = 0.036).There was incremental significant decrease in GLS with increasing number of coronary vessels involved. CONCLUSION: Measurement of global longitudinal strain using 2D speckle tracking echocardiography is sensitive and accurate tool in the prediction of severe CAD.

17.
JACC Basic Transl Sci ; 1(4): 193-202, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30167512

RESUMEN

The selection of appropriate candidates for mitral surgery among symptomatic patients with nonischemic, chronic, secondary severe mitral regurgitation (NICSMR) remains a clinical challenge. We studied 50 consecutive symptomatic NICSMR patients for a median follow-up of 2.5 years after mitral surgery and concluded that the pre-operative 2-dimensional speckle tracking echocardiography-derived left ventricular torsional profile and QRS width/cardiac resynchronization therapy are potentially important prognostic indicators for post-surgery survival and reverse remodeling.

18.
JACC Basic Transl Sci ; 1(7): 633-643, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30167547

RESUMEN

PF-1355 is an oral myeloperoxidase (MPO) inhibitor that successfully decreased elevated MPO activity in mouse myocardial infarction models. Short duration PF-1355 treatment for 7 days decreased the number of inflammatory cells and attenuated left ventricular dilation. Cardiac function and remodeling improved when treatment was increased to 21 days. Better therapeutic effect was further achieved with early compared with delayed treatment initiation (1 h vs. 24 h after infarction). In conclusion, PF-1355 treatment protected a mouse heart from acute and chronic effects of MI, and this study paves the way for future translational studies investigating this class of drugs in cardiovascular diseases.

19.
Int J Cardiol Heart Vasc ; 11: 66-73, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28616528

RESUMEN

BACKGROUND: It has been reported that contractility, as assessed using dobutamine infusion, is independently associated with reverse remodeling after CRT. Controversy, however, exists about the capacity of this approach to predict a long-term clinical response. This study's purpose was to assess whether long-term CRT clinical effects can be predicted according to acute inotropic response induced by biventricular stimulation (CRT on), as compared with AAI-VVI right stimulation pacing mode (CRT off), quantified at the time of implantation. METHODS: In 98 patients (ejection fraction 29 ± 10%), acute changes in left ventricular (LV) elastance (Ees), arterial elastance (Ea), and Ees/Ea, as assessed from slope changes of the force-frequency relation obtained when the heart rate increased, and also assessed while measuring triplane LV volumes and continuous noninvasive blood pressure, were related to death or rehospitalization during a 3-year follow-up. Other covariances tested were age, gender, disease etiology, QRS duration, amount of mitral regurgitation, LV diastolic volume, ejection fraction, and the degree of asynchrony and longitudinal strain at baseline. RESULTS: There was a marked increment in the Ees slope with CRT (interaction P = 0.004), no Ea change, and modest Ees/Ea increase (interaction P < 0.05). In Cox analysis, however, neither slope changes nor baseline values of Ees, Ea, and Ees/Ea were associated with long-term follow-up. Only ventricular diastolic volume (direct relation P = 0.002) and QRS duration (inverse relation P = 0.009) predicted death/rehospitalization. CONCLUSIONS: Acute contractile recovery in CRT patients is not associated with 3 years prognosis. Instead, death or rehospitalization can be predicted from QRS duration and LV diastolic volume at baseline.

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