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We aimed to characterize the echocardiographic alterations in dogs from an endemic region that were naturally infected with T. cruzi. Dogs (n = 130) seropositive for antibodies against T. cruzi and/or with acute parasitemia were enrolled in the study. Indicators of changes in the structure and systolic and diastolic functions of the left ventricle (LV) and blood flow patterns were evaluated by echocardiography. The frequency and extent of alterations in these indicators were associated with the severity of the disease. Briefly, 15 (11.54%) dogs were diagnosed with dilated cardiomyopathy (DCM), and 115 (88.46%) dogs were diagnosed as being without DCM. Infected dogs with DCM exhibited structural features of LV dysfunction, e.g., a significant (p < 0.05) increase in the LV internal diameter at systole and diastole (LVID-s, LVID-d) and a decline in the LV posterior wall (LVPW-d) thickness at diastole. Despite an increase in stroke volume and cardiac output indicating contraction force, DCM resulted in a decreased ejection fraction, affecting systolic function. Dogs that were diagnosed as DCM-negative but were positive for T. cruzi by PCR exhibited a high frequency of an increase in the thickness of the interventricular septum in systole (IVS-s) and the LV posterior wall in diastole (LVPW-d), a decline in the LV inner diameter (LVID-d, LVID-s), and fractional shortening (FS). The thinning of the LVPW at systole was the most defining feature observed in chronically infected dogs. In summary, this is the first study reporting the echocardiographic changes occurring in dogs naturally infected with T. cruzi and developing DCM. Our data suggest that changes in LVID are a major indicator of risk of cardiac involvement, and the observation of changes in the IVS, LVPW, and FS have predictive value in determining the risk of DCM development in infected dogs.

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Objectives: The study aimed to know the clinical, demographic, diagnostic, and treatments characteristics in patients with cardiomyopathies in Mexico. Methods: The Mexican Registry of Cardiomyopathies (REMEMI) is an observational, prospective and national study of patients with cardiomyopathies, which includes: Dilated cardiomyopathy (DCM), hypertrophic cardiomyopathy (HCM), restrictive cardiomyopathy (RCM) and arrhythmogenic cardiomyopathy of the right ventricle (ARVC). Results: A total of 1026 patients from most states of the Mexican Republic (19) were included, with 494 corresponding to DCM, 490 to HCM, 35 to RCM, and seven to ARVC. We found significant differences between the various cardiomyopathy phenotypes (p < 0.05) in the coexistence with diabetes, use of implantable defibrillator, presence of ventricular tachycardia, and NYHA functional class ≥ 1. There were no significant differences in age and predominant gender between each one. When analyzing by phenotype, we found that patients with HCM have limited use of diagnostic methods considered indispensable, such as cardiac magnetic resonance, Holter monitoring, and genetic testing in patients and their relatives. Conclusion: Seeking contemporary information through observational registries in Mexico is a valuable opportunity to understand the characteristics of the methods used in the study and treatment of diseases such as cardiomyopathies by Mexican physicians. It can provide information for the implementation of management guidelines and strategies to disseminate findings to improve healthcare in our country.

Objetivo: Conocer las características clínicas y demográficas, así como las herramientas diagnósticas y tratamientos utilizados en pacientes con miocardiopatías en México. Métodos: El Registro Mexicano de Miocardiopatías (REMEMI) es un estudio observacional, prospectivo y nacional de pacientes con diagnóstico de miocardiopatía, que incluye: miocardiopatía dilatada (MCD), miocardiopatía hipertrófica (MCH), miocardiopatía restrictiva (MCR) y miocardiopatía arritmogénica del ventrículo derecho (MAVD). Resultados: Se incluyó un total de 1026 pacientes provenientes de la mayoría de los estados de la República Mexicana (19), de los cuales 494 corresponden a MCD, 490 a MCH, 35 a MCR y 7 a MAVD. Encontramos diferencias significativas entre los diversos fenotipos de miocardiopatías (p < 0.05) en la coexistencia con diabetes, empleo de desfibrilador implantable, presencia de taquicardia ventricular y la clase funcional de la NYHA ≥ 1. No hubo diferencias significativas en la edad y sexo predominante entre cada uno. Al analizar por fenotipo encontramos que la MCH tienen poco empleo de métodos diagnósticos considerados como indispensables como la resonancia magnética cardiaca, el monitoreo Holter y el estudio genético en los pacientes y sus familiares. Conclusión: La búsqueda de información contemporánea a través de registros observacionales en México es una buena oportunidad para conocer las características de los métodos empleados en el estudio y tratamiento de enfermedades como las miocardiopatías por médicos mexicanos, y puede ofrecernos información para la implementación de guías de manejo y estrategias de difusión de los hallazgos para así mejorar el cuidado de la salud en nuestro país.

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This case report details the identification of a novel likely pathogenic splicing variant in the TTN gene, associated with dilated cardiomyopathy (DCM), in a 42-year-old male patient presenting with early-onset heart failure and reduced ejection fraction. DCM is a nonischemic heart condition characterized by left biventricular dilation and systolic dysfunction, with approximately one-third of cases being familial and often linked to genetic mutations. The TTN gene, encoding the largest human protein essential for muscle contraction and sarcomere structure, is implicated in about 25% of DCM cases through mutations, especially truncating variants. Our investigation revealed a previously unreported G > C mutation at the splice acceptor site in intron 356 of TTN, confirmed by Sanger sequencing and not found in population databases, suggesting a novel contribution to the understanding of DCM etiology. The case emphasizes the critical role of the TTN gene in cardiac function and the genetic complexity underlying DCM. A comprehensive literature review highlighted the prevalence and significance of splice variants in the TTN gene, particularly those affecting the titin A-band, which is known for its role in muscle contraction and stability. This variant's identification underscores the importance of genetic screening in patients with DCM, offering insights into the disease's familial transmission and potential therapeutic targets. Our findings contribute to the expanding knowledge of genetic factors in DCM, demonstrating the necessity of integrating genetic diagnostics in cardiovascular medicine. This case supports the growing evidence linking splicing mutations in specific regions of the TTN gene to DCM development and underscores the importance of genetic counseling and testing in managing heart disease.

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Introduction: Dilated cardiomyopathy (DCM) is a fatal myocardial condition with ventricular structural changes and functional deficits, leading to systolic dysfunction and heart failure (HF). DCM is a frequent complication in oncologic patients receiving Doxorubicin (Dox). Dox is a highly cardiotoxic drug, whereas its damaging spectrum affects most of the organs by multiple pathogenic cascades. Experimentally reproduced DCM/HF through Dox administrations has shed light on the pathogenic drivers of cardiotoxicity. Growth hormone (GH) releasing peptide 6 (GHRP-6) is a GH secretagogue with expanding and promising cardioprotective pharmacological properties. Here we examined whether GHRP-6 administration concomitant to Dox prevented the onset of DCM/HF and multiple organs damages in otherwise healthy rats. Methods: Myocardial changes were sequentially evaluated by transthoracic echocardiography. Autopsy was conducted at the end of the administration period when ventricular dilation was established. Semiquantitative histopathologic study included heart and other internal organs samples. Myocardial tissue fragments were also addressed for electron microscopy study, and characterization of the transcriptional expression ratio between Bcl-2 and Bax. Serum samples were destined for REDOX system balance assessment. Results and discussion: GHRP-6 administration in parallel to Dox prevented myocardial fibers consumption and ventricular dilation, accounting for an effective preservation of the LV systolic function. GHRP-6 also attenuated extracardiac toxicity preserving epithelial organs integrity, inhibiting interstitial fibrosis, and ultimately reducing morbidity and mortality. Mechanistically, GHRP-6 proved to sustain cellular antioxidant defense, upregulate prosurvival gene Bcl-2, and preserve cardiomyocyte mitochondrial integrity. These evidences contribute to pave potential avenues for the clinical use of GHRP-6 in Dox-treated subjects.

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Background: Tumour-producing catecholamines arise in the adrenal medulla (pheochromocytomas), as well as in extra-adrenal chromaffin cells (paragangliomas). The origin can be from any location; however, it is very rare in the heart. Case summary: A 43-year-old woman with a history of arterial hypertension presented with dyspnoea on moderate exertion, New York Class Association (NYHA) functional classes III and IV, and oedema in the lower extremities. Medical and laboratory evaluation revealed an NT-proBNP of 6046 pg/mL, a left ventricular ejection fraction (LVEF) of 15%, longitudinal strain of -7%, and a mass located on the inner surface of the left atrioventricular groove. Surgical intervention was performed, and the tumour was resected. Pathological report showed an extra-adrenal paraganglioma without neoplastic involvement in the margins of the vena cava. After surgery, the patient showed clinical improvement with NYHA functional class I, LVEF of 56%, and longitudinal strain of -20% on transthoracic echocardiography 4 months after treatment. Discussion: Paragangliomas are tumours that are rarely found in the heart, and their diagnosis is difficult. However, early detection and treatment can improve the quality of life of affected patients.

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The case of a 49-year-old man with acute onset of heart failure is presented. The initial work-up showed a dilated cardiomyopathy with severely reduced left ventricular ejection fraction. In the differential diagnostic process, hypertensive, ischaemic, and valvular aetiologies were discarded. Subsequently, a cardiac magnetic resonance revealed global hypokinesis and inferior and anterior subepicardial fibrosis. Once differential diagnoses of subepicardial fibrosis (myocarditis, sarcoidosis, and Chagas disease) were discarded, a genetic panel was performed, resulting in a heterozygous mutation of desmoplakin (DSP) gene c.6697_6698del. A left-dominant DSP arrhythmogenic cardiomyopathy mutation was diagnosed. Structural myocardial abnormalities and ventricular arrhythmias characterize arrhythmogenic cardiomyopathy. Up to 50% of cases are associated with mutations in DSP genes (JUP, DSP, and PKP2). DSP is the fundamental component of the desmosome structure and provides structural support through intercellular adhesion. Therefore, when frequent differential diagnoses are discarded, genetic studies for dilated cardiomyopathy and DSP mutation should be considered.

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La hemocromatosis es una enfermedad caracterizada por el excesivo depósito de hierro en múltiples órganos, entre ellos hígado, páncreas, piel y corazón. La infiltración de este último es un importante factor en morbilidad y mortalidad. Presentamos un caso de un paciente pediátrico con insuficiencia cardíaca terminal que ameritó trasplante cardíaco, que resultó sin complicaciones. Posterior a la cirugía, mostró mejoría bioquímica y clínica, lo que influyó positivamente en su calidad de vida y prolongó su supervivencia.

Hemochromatosis is a disease characterized by excess iron stores in multiple organs, including the liver, pancreas, skin, and heart. The infiltration of the heart is an important factor in morbidity and mortality. Here we describe the case of a pediatric patient with end-stage heart failure who required a heart transplantation, with no complications. After the surgery, she showed biochemical and clinical improvement, with a positive impact on her quality of life and a prolonged survival.

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Chagas disease (CD) is caused by the protozoan Trypanosoma cruzi, and affects seven million people in Latin America. Side effects and the limited efficacy of current treatment have led to new drug research. The objective of this work was to evaluate the effectiveness of nitazoxanide (NTZ) and electrolyzed oxidizing water (EOW) in a canine model of experimental CD. Náhuatl dogs were infected with the T. cruzi H8 strain and NTZ- or EOW-treated orally for 10 days. Seronegativity was shown at 12 months post-infection (mpi) in the NTZ-, EOW-, and benznidazole (BNZ)-treated groups. The NTZ and BNZ groups had high levels of IFN-γ, TNF-α, IL-6, IL-12B, and IL-1ß at 1.5 mpi and low levels of IL-10. Electrocardiographic studies showed alterations from 3 mpi and worsening at 12 mpi; NTZ treatment produced fewer cardiac pathomorphological changes compared to EOW, similar to BNZ treatment. There was no cardiomegaly in any group. In conclusion, although NTZ and EOW did not prevent changes in cardiac conductivity, they were able to avoid the severity of heart damage in the chronic phase of CD. NTZ induced a favorable proinflammatory immune response after infection, being a better option than EOW as a possible treatment for CD after BNZ.

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Exponemos la experiencia del Instituto Nacional de Cardiología de una serie de casos de pacientes sometidos a trasplante cardiaco entre mayo de 2016 y junio 2022. Se realizaron 14 trasplantes, 13 fueron del sexo masculino. La edad osciló entre 19 y 62 años. Las etiologías fueron cardiopatías de tipo idiopática en 57% y valvular en 21%. El 50% se trasplantó en INTERMACS 4 (Interagency Registry for Mechanically Assisted Circulatory Support), 21% INTERMACS 3 y solo 28% en INTERMACS 2. Tres pacientes se trasplantaron con asistencia circulatoria tipo membrana circulación extracorpórea. Las complicaciones más frecuentes fueron las infecciosas. La mortalidad hospitalaria fue 35,7%. Hubo un fallecido en el seguimiento tras 5 años de trasplante.

We present the experience of the National Institute of Cardiology of a series of cases of patients undergoing heart transplantation between May 2016 and June 2022. Fourteen transplants were performed, 13 of the patients were male. The age ranged between 19 and 62 years. The etiologies were idiopathic heart disease in 57% and valvular heart disease in 21%. Fifty percent was transplanted in INTERMACS 4 (Interagency Registry for Mechanically Assisted Circulatory Support), 21% in INTERMACS 3 and only 28% in INTERMACS 2. Three patients were transplanted with membrane type extracorporeal circulation circulatory support. The most frequent complications were infectious. Hospital mortality was 35.7%. There was one patient who died during follow-up after 5 years of transplantation.

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Hemochromatosis is a disease characterized by excess iron stores in multiple organs, including the liver, pancreas, skin, and heart. The infiltration of the heart is an important factor in morbidity and mortality. Here we describe the case of a pediatric patient with end-stage heart failure who required a heart transplantation, with no complications. After the surgery, she showed biochemical and clinical improvement, with a positive impact on her quality of life and a prolonged survival.

La hemocromatosis es una enfermedad caracterizada por el excesivo depósito de hierro en múltiples órganos, entre ellos hígado, páncreas, piel y corazón. La infiltración de este último es un importante factor en morbilidad y mortalidad. Presentamos un caso de un paciente pediátrico con insuficiencia cardíaca terminal que ameritó trasplante cardíaco, que resultó sin complicaciones. Posterior a la cirugía, mostró mejoría bioquímica y clínica, lo que influyó positivamente en su calidad de vida y prolongó su supervivencia.

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We will report a case of a desmoid tumour (DT), which developed at the surgical site of the pacemaker after a late childhood heart transplant. Patients with idiopathic dilated cardiomyopathy followed up in the paediatric cardiology service. It evolved with the dissociation of ventricular rhythm caused by severe heart failure, which led to the implantation of a cardiac resynchronization device prior to heart transplantation. The progression to end-stage heart disease culminated in a heart transplant at 12 years old. One year after the transplant, at the age of 13 years, he presented a progressively growing mass on the generator site of the resynchronization device. The initial decision was to remove the device. During the removal surgery, there was no haematoma or fluid collection. However, there was a progression of the lesion. The lesion was biopsied with the anatomopathological diagnosis of a DT. Resection surgery happened 4 months after the start of the mass growth. At that time, the tumour reached 20 cm in diameter. The lesion infiltrated the pectoralis major muscle and this muscle was resected partially en bloc with the lesion. The defect had primary closure. The patient evolved without postoperative complications and was discharged on the 14th postoperative day. The surgical specimen came with negative circumferential margins. However, the deep margin was microscopically positive. Due to deep involvement, the patient underwent adjuvant radiotherapy. Currently, the patient is under clinical follow-up and has no evidence of tumour recurrence. DT is a rare tumour, with unpredictable courses. Surgery can be considered in the progression of lesions. Treatment is justified by long survival after a heart transplant and in DT patients. DT is a differential diagnosis to be considered in progressive growth lesions.

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BACKGROUND: Cardiomyocytes synthesize, utilize and reuptake serotonin, which is involved in the paracrine and autocrine modulation of heart activity and in the pathophysiology of some cardiovascular diseases. OBJECTIVE: To determine the expression of tryptophan-5-hydroxylase (TPH) 1 and 2, serotonin transporter protein (SERT) and serotonergic receptors in hearts with dilated cardiomyopathy (DCM) compared to controls. METHOD: A comparative study was performed in six tissue blocks of the left ventricular free wall (LVWL) and inter-ventricular septum from patients who died of DCM and six who died of no cardiovascular diseases (controls). Five slices from each block were obtained to determine the expression of TPH1 and TPH2, SERT and serotonergic receptors with antibodies specific for immunofluorescence. Immunofluorescence was analyzed by Student's t-test, accepting a significance level of p < 0.05. RESULTS: An increase in TPH1, TPH2, 5-HT2A and 5-HT2B receptors expression were observed in dilated structures compared to controls (p < 0.05). For dilated inter-ventricular septum, the 5-HT4 receptor increased its expression (p < 0.05), and SERT in PLVI compared to controls (p < 0.05). CONCLUSIONS: These results suggest that the increases observed in the expression of TPH, SERT, and serotonergic receptors in hearts with DCM compared to controls could play an important role in the pathophysiology of MCD in humans.

ANTECEDENTES: Los cardiomiocitos sintetizan, utilizan y recapturan serotonina, la cual participa en la modulación parácrina y autócrina de la actividad del corazón y en la fisiopatología de algunas enfermedades cardiovasculares. OBJETIVO: Determinar la expresión de triptófano-5-hidroxilasa (TPH) 1 y 2, transportador de serotonina (SERT) y receptores serotoninérgicos en corazones con miocardiopatía dilatada (MCD) en comparación con controles. MÉTODO: Estudio comparativo en seis bloques de la pared libre del ventrículo izquierdo (PLVI) y del septum interventricular de pacientes fallecidos por MCD y seis que murieron por enfermedades no cardiovasculares. Se obtuvieron cinco cortes de cada bloque para determinar la expresión de TPH1 y TPH2, SERT y receptores serotoninérgicos con anticuerpos específicos por inmunofluorescencia. La inmunofluorescencia fue analizada por la t de Student, aceptando un nivel de significancia de p < 0.05. RESULTADOS: Se observó un aumento en la expresión de TPH1 y TPH2 y en los receptores 5-HT2A y 5-HT2B en las estructuras dilatadas en comparación con las controles (p < 0.05). El receptor 5-HT4 aumentó su expresión en el septum interventricular dilatado (p < 0.05) y el SERT en la PLVI en comparación con los controles (p < 0.05). CONCLUSIONES: Estos resultados sugieren que los aumentos observados en las expresiones de TPH, SERT y receptores serotoninérgicos en corazones con MCD en comparación con controles podrían desempeñar un papel importante en la fisiopatología de la MCD en los humanos.

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Neuromuscular diseases represent a rare cause of dilated myocardiopathy, among them Duchenne muscular dystrophy is the most common. Transthoracic echocardiography and cardiac magnetic resonance imaging can assess cardiac involvement early. The case of a patient diagnosed with Duchenne muscular dystrophy who develops cardiac involvement during cardiology follow-up is presented below.

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The clinical phenotype of LMNA-associated dilated cardiomyopathy (DCM) varies even among individuals who share the same mutation. LMNA encodes lamin AC, which interacts with the lamin-associated protein 2 alpha (LAP2α) encoded by the TMPO gene. The LAP2α/Arg690Cys polymorphism is frequent in Latin America and was previously found to disrupt LAP2α-Lamin AC interactions in vitro. We identified a DCM patient heterozygous for both a lamin AC truncating mutation (Ser431*) and the LAP2α/Arg690Cys polymorphism. We performed protein modeling and docking experiments, and used confocal microscopy to compare leukocyte nuclear morphology among family members with different genotype combinations (wild type, LAP2α Arg690Cys heterozygous, lamin AC/Ser431* heterozygous, and LAP2α Arg690Cys/lamin AC Ser431* double heterozygous). Protein modeling predicted that 690Cys destabilizes the LAP2α homodimer and impairs lamin AC-LAP2α docking. Lamin AC-deficient nuclei (Ser431* heterozygous) showed characteristic blebs and invaginations, significantly decreased nuclear area, and increased elongation, while LAP2α/Arg690Cys heterozygous nuclei showed a lower perimeter and higher circularity than wild-type nuclei. LAP2α Arg690Cys apparently attenuated the effect of LMNA Ser431* on the nuclear area and fully compensated for its effect on nuclear circularity. Altogether, the data suggest that LAP2α/Arg690Cys may be one of the many factors contributing to phenotype variation of LMNA-associated DCM.

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Resumo Fundamento: A disfunção hepática é uma variável postulada de prognóstico desfavorável na cardiomiopatia dilatada (CMD). Objetivo: Este estudo teve como objetivo investigar o valor prognóstico do escore albumina-bilirrubina (ALBI), um modelo relativamente novo para a avaliação da função hepática, em pacientes com CMD idiopática. Métodos: Um total de 1.025 pacientes com CMD idiopática foram incluídos retrospectivamente e divididos em três grupos com base nos escores de ALBI: grau 1 (≤ −2,60, n = 113), grau 2 (−2,60 a −1,39, n = 835) e grau 3 (> −1,39, n = 77). Foi analisada a associação do escore ALBI com eventos clínicos adversos maiores (ECAM) intra-hospitalares e mortalidade a longo prazo. Valor de p inferior a 0,05 foi considerado estatisticamente significativo. Resultados: A taxa de ECAM intra-hospitalares foi significativamente maior nos pacientes com grau 3 (2,7% versus 7,1% versus 24,7%, p < 0,001). A análise multivariada mostrou que o escore ALBI foi um preditor independente para ECAM intra-hospitalares (odds ratio ajustada = 2,80, IC 95%: 1,63 - 4,80, p < 0,001). Após seguimento mediano de 27 meses, 146 (14,2%) pacientes morreram. A curva de Kaplan-Meier indicou que a taxa cumulativa de sobrevida a longo prazo foi significativamente menor em pacientes com grau mais alto de ALBI (log-rank = 45,50, p < 0,001). O escore ALBI foi independentemente associado à mortalidade a longo prazo (hazard ratio ajustada = 2,84, IC 95%: 1,95 - 4,13, p < 0,001). Conclusão: O escore ALBI, como modelo de risco simples, pode ser considerado uma ferramenta de estratificação de risco para pacientes com CMD idiopática.

Abstract Background: Liver dysfunction is a postulated variable for poor prognosis in dilated cardiomyopathy (DCM). Objective: This study aimed to investigate the prognostic value of the albumin-bilirubin (ALBI) score, a relatively new model for evaluating liver function, in patients with idiopathic DCM. Methods: A total of 1025 patients with idiopathic DCM were retrospectively included and divided into three groups based on ALBI scores: grade 1 (≤ −2.60, n = 113), grade 2 (−2.60 to −1.39, n = 835), and grade 3 (> −1.39, n = 77). The association of ALBI score with in-hospital major adverse clinical events (MACEs) and long-term mortality was analyzed. P-value less than 0.05 was considered statistically significant. Results: The in-hospital MACEs rate was significantly higher in the grade 3 patients (2.7% versus 7.1% versus 24.7%, p < 0.001). Multivariate analysis showed that ALBI score was an independent predictor for in-hospital MACEs (adjusted odds ratio = 2.80, 95%CI: 1.63 - 4.80, p < 0.001). After a median 27-month follow-up, 146 (14.2%) patients died. The Kaplan-Meier curve indicated that the cumulative rate of long-term survival was significantly lower in patients with higher ALBI grade (log-rank = 45.50, p < 0.001). ALBI score was independently associated with long-term mortality (adjusted hazard ratio = 2.84, 95%CI: 1.95 - 4.13, p < 0.001). Conclusion: ALBI score as a simple risk model could be considered a risk-stratifying tool for patients with idiopathic DCM.

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Barth syndrome (BTHS) and dilated cardiomyopathy with ataxia syndrome (DCMA) are biochemically characterized by high levels of 3-methylglutaric acid (MGA) in the urine and plasma of affected patients. Although cardiolipin abnormalities have been observed in these disorders, their pathophysiology is not fully established. We evaluated the effects of MGA administration on redox homeostasis and mitochondrial function in heart, as well as on vascular reactivity in aorta of Wistar rats without cardiolipin genetic deficiency. Potential cardioprotective effects of a pretreatment with bezafibrate (BEZ), a pan-PPAR agonist that induces mitochondrial biogenesis, were also determined. Our findings showed that MGA induced lipid peroxidation, altered enzymatic and non-enzymatic antioxidant defenses and reduced respiratory chain function in rat heart. MGA also increased Drp1 and reduced MFN1 levels, suggesting mitochondrial fission induction. Moreover, MGA altered MAPK and Akt signaling pathways, and had a strong tendency to reduce Sirt1 and PGC-1α, indicative of mitochondrial biogenesis impairment. Aorta vascular reactivity was further altered by MGA. Additionally, BEZ mitigated most alterations on antioxidant defenses and mitochondrial quality control proteins provoked by MGA. However, vascular reactivity disturbances were not prevented. It may be presumed that oxidative stress, mitochondrial bioenergetics and control quality disturbances, and vascular reactivity impairment caused by MGA may be involved in the cardiac failure observed in BTHS and DCMA, and that BEZ should be considered as a pharmacological candidate for the treatment of these disorders.

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Cardiomyopathy is commonly observed in patients with autosomal dominant polycystic kidney disease (ADPKD), even when they have normal renal function and arterial pressure. The role of cardiomyocyte polycystin-1 (PC1) in cardiovascular pathophysiology remains unknown. PC1 is a potential regulator of BIN1 that maintains T-tubule structure, and alterations in BIN1 expression induce cardiac pathologies. We used a cardiomyocyte-specific PC1-silenced (PC1-KO) mouse model to explore the relevance of cardiomyocyte PC1 in the development of heart failure (HF), considering reduced BIN1 expression induced T-tubule remodeling as a potential mechanism. PC1-KO mice exhibited an impairment of cardiac function, as measured by echocardiography, but no signs of HF until 7-9 months of age. Of the PC1-KO mice, 43% died suddenly at 7 months of age, and 100% died after 9 months with dilated cardiomyopathy. Total BIN1 mRNA, protein levels, and its localization in plasma membrane-enriched fractions decreased in PC1-KO mice. Moreover, the BIN1 + 13 isoform decreased while the BIN1 + 13 + 17 isoform was overexpressed in mice without signs of HF. However, BIN1 + 13 + 17 overexpression was not observed in mice with HF. T-tubule remodeling and BIN1 score measured in plasma samples were associated with decreased PC1-BIN1 expression and HF development. Our results show that decreased PC1 expression in cardiomyocytes induces dilated cardiomyopathy associated with diminished BIN1 expression and T-tubule remodeling. In conclusion, positive modulation of BIN1 expression by PC1 suggests a novel pathway that may be relevant to understanding the pathophysiological mechanisms leading to cardiomyopathy in ADPKD patients.

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High-output heart failure (HF) is an uncommon condition. This occurs when HF syndrome patients have a cardiac output higher than eight litres per minute. Shunts, such as fistulas and arteriovenous malformations are an important reversible cause. We present the case of a 30-year-old man who presented to the emergency department due to decompensated HF. Echocardiogram showed dilated myocardiopathy with high cardiac output (19.5 L/min calculated on long-axis view). He was diagnosed with arteriovenous malformation by computed tomography (CT) and subsequent angiography, and a multi-disciplinary team decided to perform endovascular embolisation with ethylene vinyl alcohol/dimethyl sulfoxide at different times. The transthoracic echocardiogram showed a significant decrease in cardiac output (9.8 L/min) and his general condition improved significantly.

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SARS-CoV-2 is an emerging cause of viral myocarditis that generates multiple complications, such as dilated cardiomyopathy. We describe a young, obese male patient with severe myocardial involvement by the SARS-CoV-2 virus, who presented with chest pain, elevated cardiac enzymes, non-specific electrocardiographic findings, echocardiogram with evidence of dilated heart disease with reduced ejection fraction, and subsequent verification using magnetic resonance imaging (MRI). The results of the cardiac MRI were typical of viral myocarditis. The patient did not respond to a short course of systemic steroids and the standard management for heart failure, had multiple re-admissions, and, unfortunately, died.