Generation of an induced pluripotent stem cell line (ESi107-A) from a transthyretin amyloid cardiomyopathy (ATTR-CM) patient carrying a p.Ser43Asn mutation in the TTR gene.

Transthyretin (TTR) amyloid cardiomyopathy (ATTR-CM) is a life-threatening disease caused by the abnormal production of misfolded TTR protein by liver cells, which is then released systemically. Its amyloid deposition in the heart is linked to cardiac toxicity and progression toward heart failure. A human induced pluripotent stem cell (iPSC) line was generated from peripheral blood mononuclear cells (PBMCs) from a patient suffering familial transthyretin amyloid cardiomyopathy carrying a c.128G>A (p.Ser43Asn) mutation in the TTR gene. This iPSC line offers a useful resource to study the disease pathophysiology and a cell-based model for therapeutic discovery.

Safety, feasibility, and hemodynamic response of regadenoson for stress perfusion CMR.

Owing to its pharmacodynamics and posology, the use of regadenoson for stress cardiac magnetic resonance (CMR) has potential advantages over other vasodilators. We sought to evaluate the safety, hemodynamic response and diagnostic performance of regadenoson stress-CMR in routine clinical practice. All regadenoson stress-CMR examinations performed between May 2017 and July 2020 at our institution were retrospectively reviewed. A total of 698 studies were included for the final analysis. A conventional stress/rest protocol was performed using a 1.5T MRI scanner (Magnetom Aera, Siemens Healthineers, Erlangen, Germany). Adverse events, clinical symptoms, and hemodynamic response were assessed. Diagnostic accuracy of the test was evaluated in patients who underwent invasive coronary angiography. Nearly half of patients (48.5%) remained asymptomatic. Most common clinical symptoms included dyspnea (137, 19.6%), chest pain (116, 16.6%) and flushing (44, 6.3%). Two patients (0.28%) could not complete the examination due to severe hypotension or unbearable chest pain. Overall, an increase in heart rate (HR) response (36.2% [IQR: 22.5?50.9]) and a decrease in systolic and diastolic blood pressure (BP) (median systolic BP response of -5% [IQR: -11.5-0.6]; median diastolic BP response of -6.3 mmHg [IQR: -13.4-0]) was observed. Patients with symptoms induced by regadenoson showed higher HR response (40.3%, IQR: 26.4?56.1 vs. 32.4%, IQR: 19-45.6, p < 0.001), whereas a blunted HR response was observed in diabetic (29.6%, IQR: 18.4?42 p < 0.001), obese (31.7%, IQR: 20.7?46.2 p = 0.005) and patients aged 70 years or older (32.9%, IQR: 22.6?43.1 p < 0.001). Overall, regadenoson stress-CMR showed 95.65% (IQ 91.49?99.81) sensitivity, 54.84% (IQ 35.71?73.97) specificity, 86.99% (IQ 82.74?94.68) positive predictive value, and 77.27% (IQ 57.49?97.06) negative predictive value for detecting significant coronary stenosis as compared with invasive coronary angiography. Regadenoson is a well-tolerated vasodilator that can be safely employed for stress perfusion CMR, with high diagnostic performance.

Fabrication of human myocardium using multidimensional modelling of engineered tissues.

Biofabrication of human tissues has seen a meteoric growth triggered by recent technical advancements such as human induced pluripotent stem cells (hiPSCs) and additive manufacturing. However, generation of cardiac tissue is still hampered by lack of adequate mechanical properties and crucially by the often unpredictable post-fabrication evolution of biological components. In this study we employ melt electrowriting (MEW) and hiPSC-derived cardiac cells to generate fibre-reinforced human cardiac minitissues. These are thoroughly characterized in order to build computational models and simulations able to predict their post-fabrication evolution. Our results show that MEW-based human minitissues display advanced maturation 28 post-generation, with a significant increase in the expression of cardiac genes such as MYL2, GJA5, SCN5A and the MYH7/MYH6 and MYL2/MYL7 ratios. Human iPSC-cardiomyocytes are significantly more aligned within the MEW-based 3D tissues, as compared to conventional 2D controls, and also display greater expression of C×43. These are also correlated with a more mature functionality in the form of faster conduction velocity. We used these data to develop simulations capable of accurately reproducing the experimental performance. In-depth gauging of the structural disposition (cellular alignment) and intercellular connectivity (C×43) allowed us to develop an improved computational model able to predict the relationship between cardiac cell alignment and functional performance. This study lays down the path for advancing in the development ofin silicotools to predict cardiac biofabricated tissue evolution after generation, and maps the route towards more accurate and biomimetic tissue manufacture.

Long-Term Prognostic Value of Coronary CTA in Orthotopic Heart Transplant Recipients.

OBJECTIVE. This study aimed to evaluate the long-term prognostic value of coronary CTA (CCTA) in heart transplant recipients. MATERIALS AND METHODS. The records of 114 patients who had undergone a heart transplant (mean age, 61.7 ± 11.1 [SD] years; 83.3% men) and who underwent CCTA for the surveillance of coronary allograft vasculopathy (CAV) from June 2007 to December 2017 were retrospectively evaluated for the occurrence of major adverse cardiovascular events (MACEs) (cardiac death, nonfatal myocardial infarction, unstable angina requiring hospitalization, coronary revascularization, cardiac arrhythmias, stroke, and retransplant). Patients were classified according to the presence of nonobstructive CAV (lumen reduction < 50%) or obstructive disease (lumen reduction ≥ 50%) and using a coronary segment involvement score (SIS). Differences in MACE rate between groups were compared. RESULTS. Obstructive CAV was observed in 12 heart transplant recipients (10.5%). During a mean follow-up of 67.5 ± 41.4 months the overall rates of MACE were 50% and 14.7% in patients with obstructive and nonobstructive CAV, respectively (p < .05), resulting in an odds ratio for MACE of 6 (95% CI, 1.7-21.2). Comparison of event-free survival showed a hazard ratio (HR) of 5 (95% CI, 1.95-13; p =. 004) for patients with obstructive disease. The presence of four or more stenotic coronary segments (SIS ≥ 4) was associated with a higher rate of events (HR, 3.46; 95% CI, 1.46-8.23). CONCLUSION. In patients who have undergone a heart transplant, CCTA offers a significant long-term prognostic impact on the prediction of MACEs.

Adenosine triphosphate (ATP) and adenosine cause similar vasodilator effect in patients undergoing stress perfusion cardiac magnetic resonance imaging.

To evaluate the vasodilator effect of adenosine triphosphate (ATP) compared with adenosine in stress perfusion cardiac magnetic resonance (CMR) examinations. A total of thirty-three patients underwent clinically indicated stress/rest perfusion CMR examination following intravenous injection of a total dose of 0.2 mmol/kg of gadobutrol. Individuals were randomly assigned to ATP (160 mcg/kg/min) or adenosine (140 mcg/kg/min). The vasodilator effect of both drugs was analyzed by comparing differences in heart rate, symptoms during stress, and semiquantitative myocardial and splenic perfusion parameters, including time, time to peak, upslope, myocardial perfusion reserve index, tissue perfusion values, splenic and myocardial signal intensity ratios, and splenic-to-myocardial signal intensity ratios. No significant difference was found in heart rate variation between the stressors (26.1 ± 19.1 bpm for ATP vs. 21.7 ± 17.3 bpm for adenosine, p = 0.52). Patients receiving ATP referred less pronounced clinical symptoms. Semiquantitative myocardial perfusion parameters were comparable, and patients in the adenosine and ATP groups showed similar myocardial perfusion reserve index values (2.34 [1.62-2.73] vs 1.63 [1.29-2.10], p = 0.07). Splenic switch off was visually confirmed in all patients and estimated spleen to myocardium ratio was similar (0.92 [0.53-1.09] vs 0.81 [0.53-0.86] with ATP and adenosine, respectively, p = 0.12). Both ATP and adenosine are potent coronary vasodilators that can be safely employed in stress-CMR. Both stressor cause similar hyperemic response. Splenic switch-off can be used to assess stress adequacy in patients undergoing stress-CMR with either adenosine or ATP.

The Hypertensive Myocardium: From Microscopic Lesions to Clinical Complications and Outcomes.

The chronic hemodynamic load imposed by hypertension on the left ventricle leads to lesions in the myocardium that result in structural remodeling, which provides support for alterations in cardiac function, perfusion, and electrical activity that adversely influence the clinical evolution of hypertensive heart disease. Management must include detecting, reducing, and reversing left ventricular hypertrophy, as well as the detection and repair of microscopic lesions responsible for myocardial remodeling. Reducing the burden associated with hypertensive heart disease can be targeted using personalized treatment. The noninvasive, biomarker-mediated identification of subsets of patients with hypertensive heart disease is essential to provide personalized treatment.

Combined catheter ablation and left atrial appendage closure as a hybrid procedure for the treatment of atrial fibrillation.

AIMS: Left atrial appendage (LAA) is the source of thrombi in up to 90% of patients with non-valvular atrial fibrillation (AF). Catheter ablation (CA) is an effective treatment for symptomatic AF and, in selected cases, LAA occlusion devices have been introduced as an alternative to oral anticoagulants (OACs). The safety and feasibility of combining CA and percutaneous LAA closure (LAAC) are unknown. METHODS AND RESULTS: Patients with symptomatic drug-refractory AF, CHADS2 score of ≥1, and CHA2DS2-VASc score ≥2 were included. Catheter ablation consisted in pulmonary vein isolation with or without roof line with radiofrequency and LAA was occluded with the Watchman or Amplatzer Cardiac Plug (ACP) devices guided by angiography and transoesophageal echocardiography. A total of 35 patients were included (71% male; 70 years). Median score was 3 on both CHA2DS2-VASc and HAS-BLED, 9% had prior stroke under OAC, and 48% had bleeding complications. Successful CA and device implantation were achieved in 97% of cases. The Watchman device was used in 29 patients and ACP in 6 patients. Periprocedural complications included three cases of cardiac tamponade. At 3 months, all patients met the criteria for successful sealing of the LAA. After a mean follow-up of 13 months (3-75), 78% of patients were free of arrhythmia recurrences and OAC was withheld in 97% of patients. CONCLUSIONS: The combination of CA and percutaneous LAAC in a single procedure is technically feasible in patients with symptomatic drug-refractory AF, high risk of stroke, and contraindications to OACs, although it is associated with a significant risk of major complications.

Epicardial delivery of collagen patches with adipose-derived stem cells in rat and minipig models of chronic myocardial infarction.

Although transplantation of adipose-derived stem cells (ADSC) in chronic myocardial infarction (MI) models is associated with functional improvement, its therapeutic value is limited due to poor long-term cell engraftment and survival. Thus, the objective of this study was to examine whether transplantation of collagen patches seeded with ADSC could enhance cell engraftment and improve cardiac function in models of chronic MI. With that purpose, chronically infarcted Sprague-Dawley rats (n = 58) were divided into four groups and transplanted with media, collagen scaffold (CS), rat ADSC, or CS seeded with rat ADSC (CS-rADSC). Cell engraftment, histological changes, and cardiac function were assessed 4 months after transplantation. In addition, Göttingen minipigs (n = 18) were subjected to MI and then transplanted 2 months later with CS or CS seeded with autologous minipig ADSC (CS-pADSC). Functional and histological assessments were performed 3 months post-transplantation. Transplantation of CS-rADSC was associated with increased cell engraftment, significant improvement in cardiac function, myocardial remodeling, and revascularization. Moreover, transplantation of CS-pADSC in the pre-clinical swine model improved cardiac function and was associated with decreased fibrosis and increased vasculogenesis. In summary, transplantation of CS-ADSC resulted in enhanced cell engraftment and was associated with a significant improvement in cardiac function and myocardial remodeling.

Controlled delivery of fibroblast growth factor-1 and neuregulin-1 from biodegradable microparticles promotes cardiac repair in a rat myocardial infarction model through activation of endogenous regeneration.

Acidic fibroblast growth factor (FGF1) and neuregulin-1 (NRG1) are growth factors involved in cardiac development and regeneration. Microparticles (MPs) mediate cytokine sustained release, and can be utilized to overcome issues related to the limited therapeutic protein stability during systemic administration. We sought to examine whether the administration of microparticles (MPs) containing FGF1 and NRG1 could promote cardiac regeneration in a myocardial infarction (MI) rat model. We investigated the possible underlying mechanisms contributing to the beneficial effects of this therapy, especially those linked to endogenous regeneration. FGF1- and NRG1-loaded MPs were prepared using a multiple emulsion solvent evaporation technique. Seventy-three female Sprague-Dawley rats underwent permanent left anterior descending coronary artery occlusion, and MPs were intramyocardially injected in the peri-infarcted zone four days later. Cardiac function, heart tissue remodeling, revascularization, apoptosis, cardiomyocyte proliferation, and stem cell homing were evaluated one week and three months after treatment. MPs were shown to efficiently encapsulate FGF1 and NRG1, releasing the bioactive proteins in a sustained manner. Three months after treatment, a statistically significant improvement in cardiac function was detected in rats treated with growth factor-loaded MPs (FGF1, NRG1, or FGF1/NRG1). The therapy led to inhibition of cardiac remodeling with smaller infarct size, a lower fibrosis degree and induction of tissue revascularization. Cardiomyocyte proliferation and progenitor cell recruitment were detected. Our data support the therapeutic benefit of NRG1 and FGF1 when combined with protein delivery systems for cardiac regeneration. This approach could be scaled up for use in pre-clinical and clinical studies.

Incidental computed tomography diagnosis of a rare triad consisting of absence of coronary sinus, persistent left superior vena cava, and scimitar syndrome.

We report a case of an unusual congenital triad consisting of absence of coronary sinus, persistent left superior vena cava and scimitar syndrome incidentally found in a CT-scan performed on a female complaining of exertional dyspnea.

Sustained release of VEGF through PLGA microparticles improves vasculogenesis and tissue remodeling in an acute myocardial ischemia-reperfusion model.

The use of pro-angiogenic growth factors in ischemia models has been associated with limited success in the clinical setting, in part owing to the short lived effect of the injected cytokine. The use of a microparticle system could allow localized and sustained cytokine release and consequently a prolonged biological effect with induction of tissue revascularization. To assess the potential of VEGF(165) administered as continuous release in ischemic disease, we compared the effect of delivery of poly(lactic-co-glycolic acid) (PLGA) microparticles (MP) loaded with VEGF(165) with free-VEGF or control empty microparticles in a rat model of ischemia-reperfusion. VEGF(165) loaded microparticles could be detected in the myocardium of the infarcted animals for more than a month after transplant and provided sustained delivery of active protein in vitro and in vivo. One month after treatment, an increase in angiogenesis (small caliber caveolin-1 positive vessels) and arteriogenesis (α-SMA-positive vessels) was observed in animals treated with VEGF microparticles (p<0.05), but not in the empty microparticles or free-VEGF groups. Correlating with this data, a positive remodeling of the heart was also detected in the VEGF-microparticle group with a significantly greater LV wall thickness (p<0.01). In conclusion, PLGA microparticle is a feasible and promising cytokine delivery system for treatment of myocardial ischemia. This strategy could be scaled up and explored in pre-clinical and clinical studies.

Cardiac resynchronization therapy-induced left ventricular reverse remodelling is associated with reduced plasma annexin A5.

AIMS: Cardiac resynchronization therapy (CRT) diminishes cardiac apoptosis and improves systolic function in heart failure (HF) patients with ventricular dyssynchrony. Plasma annexin A5 (AnxA5), a protein related to cellular damage, is associated with systolic dysfunction. We investigated whether the response to CRT is associated with plasma AnxA5. We also studied AnxA5 overexpression effects in HL-1 cardiomyocytes. METHODS AND RESULTS: AnxA5 ELISA was performed in plasma from 57 patients with HF and ventricular dyssynchrony at baseline and after 1 year of CRT. Patients were categorized as responders if they presented both a reduction in left ventricular (LV) end-systolic volume index (LVESVi) >10% and an increase in LV ejection fraction (LVEF) >10%. HL-1 cells were transfected with human AnxA5 cDNA, and AnxA5, PKC, Akt, p38MAPK, Bcl-2, mitochondrial integrity, caspase-3, and ATP were assessed. At baseline, an increased plasma AnxA5 level was associated with decreased LVEF and increased LVEDVi values (P < 0.05). No differences in baseline AnxA5 were observed between responders and non-responders. After CRT, AnxA5 decreased (P = 0.001) in responders but remained unchanged in non-responders. Final values of AnxA5 were independently associated with LVEF (r = -0.387, P = 0.003) and LVESVi (r = 0.403, P = 0.004) in all patients. Compared with control cells, AnxA5-transfected cells exhibited AnxA5 overexpression, decreased PKC and Akt and increased p38MAPK and Bcl-2 phosphorylation, loss of mitochondrial integrity, caspase-3 activation, and decreased ATP. CONCLUSION: CRT-induced LV reverse remodelling is associated with reduction in plasma AnxA5. The excess of AnxA5 is detrimental for HL-1 cardiomyocytes. Collectively, these data suggest that the beneficial effects of CRT might be related to an AnxA5 decrease.

Terapia de resincronización cardiaca y miocardiopatía valvular tras cirugía correctora / Cardiac rResynchronization therapy and valvular cardiomyopathy after corrective surgery

La terapia de resincronización cardiaca (TRC) ha mostrado utilidad terapéutica en un determinado grupo de pacientes con insuficiencia cardiaca avanzada. Sin embargo, los pacientes con diagnóstico de miocardiopatía de origen valvular están infrarrepresentados en los estudios clínicos aleatorizados. El objetivo del estudio fue evaluar el efecto de la TRC en pacientes con insuficiencia cardiaca de etiología exclusivamente valvular a medio plazo (6 meses). Se incluyó a 40 pacientes consecutivos a quienes se implantó un dispositivo de resincronización cardiaca. A los 6 meses de seguimiento, se produjo una mejora de la clase funcional, el remodelado ventricular izquierdo y los parámetros de asincronía intraventricular en los pacientes tratados. En este subgrupo de pacientes, la TRC muestra un beneficio similar al obtenido en pacientes con insuficiencia cardiaca de otra etiología (AU)

Cardiac resynchronization therapy (CRT) has been shown to have clinical benefits in certain groups of patients with advanced heart failure (HF). However, patients with valvular cardiomyopathy are underrepresented in randomized clinical studies. The aim of this study was to assess the medium-term (i.e., at 6 months) effects of CRT in patients with HF exclusively due to valvular disease. The study included 40 consecutive patients who underwent CRT device implantation. At 6 months, there were improvements in functional class, left ventricular remodeling, and intraventricular dyssynchrony parameters in treated patients. In this particular subgroup of patients, the benefits of CRT were similar to those observed in patients with HF due to other etiologies (AU)

Cardiac resynchronization therapy and valvular cardiomyopathy after corrective surgery.

Cardiac resynchronization therapy (CRT) has been shown to have clinical benefits in certain groups of patients with advanced heart failure (HF). However, patients with valvular cardiomyopathy are underrepresented in randomized clinical studies. The aim of this study was to assess the medium-term (i.e., at 6 months) effects of CRT in patients with HF exclusively due to valvular disease. The study included 40 consecutive patients who underwent CRT device implantation. At 6 months, there were improvements in functional class, left ventricular remodeling, and intraventricular dyssynchrony parameters in treated patients. In this particular subgroup of patients, the benefits of CRT were similar to those observed in patients with HF due to other etiologies.

Impact of collagen type I turnover on the long-term response to cardiac resynchronization therapy.

AIMS: We investigated whether collagen type I turnover influences the long-term response to cardiac resynchronization therapy (CRT). METHODS AND RESULTS: Serum carboxy-terminal propeptide of procollagen type I or PICP (a marker of collagen type I synthesis) and carboxy-terminal telopeptide of collagen type I or CITP (a marker of collagen type I degradation) were measured in heart failure patients at baseline and after 1 year of CRT. Patients were categorized as responders or non-responders if they increased the distance walked in 6 min by > or <10%, respectively. At baseline, the PICP:CITP ratio, an index of the degree of coupling between collagen type I synthesis and degradation was higher (P = 0.006) in responders than in non-responders. Whereas the PICP:CITP ratio decreased (P= 0.000) after treatment in responders, it remained unchanged in non-responders. Thus, at 1-year, the PICP:CITP ratio was similar in the two groups of patients. A direct correlation (r = 0.289, P = 0.037) was found between the baseline PICP:CITP ratio and the change in the distance walked in 6 min in all patients. Receiver operating characteristics curves showed that a cut-off value of 14.4 for the PICP:CITP ratio provided 70% specificity and 63% sensitivity for the predicting response to CRT with a relative risk of 2.07 (95% confidence interval, 0.98-4.39). CONCLUSION: Collagen type I turnover influences the long-term response to CRT. In addition, the ability of CRT to restore the balance between collagen type I synthesis and degradation is associated with a beneficial response.

Can bone marrow-derived multipotent adult progenitor cells regenerate infarcted myocardium?

OBJECTIVES: To assess the functional effects of multipotent adult progenitor cells (MAPCs) transplanted in a rat model of chronic myocardial infarction. METHODS: Forty-four rats underwent coronary ligation and, 14 days later, were randomly allocated to receive in-scar injections (5 x 10(6) cells/150 microL) of green fluorescent protein (eGFP)-transduced allogeneic MAPCs (n = 25) or culture medium (controls, n = 19). Nine of the MAPC-treated hearts were employed for functional studies while the remaining 16 received cells co-labeled with Resovist and were only used for serial histological assessments. Left ventricular (LV) function was assessed echocardiographically before transplantation and 1 month thereafter in a blinded manner. Immunohistochemistry, electron microscopy and PCR were used to detect grafted cells. All data were compared by nonparametric tests. RESULTS: Baseline ejection fractions (EF, median;[interquartile range]) did not differ significantly among the groups: 30% [0.23;0.37] and 37% [0.32;0.38] in control and rMAPC-transplanted hearts, respectively. One month later, LV function of control hearts was found to have deteriorated, as reflected by a decline in EF to 24% [0.21;0.30], and although EF tended to remain more stable after cell transplantation (37% [0.27;0.41]), the difference between the two groups failed to achieve statistical significance (p = 0.06). While MAPCs could be identified early post-transplant, no evidence of engraftment was further observed at 1 month by immunohistochemistry, electron microscopy or PCR. CONCLUSIONS: In this model, MAPCs did not improve global pump function, and although some of these cells expressed endothelial markers during the early post-transplant period, we could not detect any evidence for differentiation into cardiomyocytes and no engraftment was further identified beyond 2 weeks after cell injections.

Autologous skeletal myoblast transplantation in patients with nonacute myocardial infarction: 1-year follow-up.

OBJECTIVE: To determine the feasibility and safety of skeletal myoblast transplantation in patients with chronic myocardial infarction undergoing coronary artery bypass grafting. METHODS: Twelve patients with a previous myocardial infarction and ischemic coronary artery disease underwent treatment with coronary artery bypass grafting surgery and intramyocardial injection of autologous skeletal myoblasts cultured with autologous serum. Global and regional cardiac function was assessed by echocardiogram. Fluorine 18 fluorodeoxyglucose and nitrogen 13-ammonia positron emission tomography studies were used to determine cardiac viability and perfusion. A group of historical control patients (n = 14) treated with coronary artery bypass grafting surgery without myoblast transplantation was analyzed. RESULTS: The left ventricular ejection fraction improved from 35.5% +/- 2.3% (mean +/- SEM) before surgery to 55.1% +/- 8.2% at 12 months (P < .01) in the myoblast group and from 33.6% +/- 9.3% to 38.6% +/- 11% in the control group. Regional contractility also improved in the myoblast group, particularly in cardiac segments treated with skeletal myoblasts (wall motion score index: 3.02 +/- 0.17 at baseline vs 1.36 +/- 0.14 at 12 months; P < .0001). Quantitative fluorine 18-fluorodeoxyglucose and nitrogen 13-ammonia positron emission tomography showed an increase in viability and perfusion 12 months after surgery both globally and in segments treated with myoblasts (P = .012 and P = .004). Skeletal myoblast implantation was not associated with adverse events or an increased incidence of cardiac arrhythmias. CONCLUSIONS: In patients with previous myocardial infarction, treatment with skeletal myoblasts in conjunction with coronary artery bypass is safe and feasible and is associated with an increased global and regional left ventricular function, improvement in viability, and perfusion of cardiac tissue and no significant incidence of arrhythmias.