Acute heart failure due to COVID-19 related myocardial injury and de novo hypertensive cardiomyopathy: a challenging diagnosis

We report a COVID-19 case with acute heart and kidney failure in a healthy young male. Echocardiography showed severe systolic and diastolic left ventricle dysfunction, with diffuse myocardial thickening. Cardiac MRI showed aspects of focal myocarditis, and hypertensive cardiomyopathy. Renal biopsy demonstrated limited acute tubular injury, and hypertensive kidney disease. Coronary angiography excluded critical stenoses. Unlike what we initially suspected, myocardial inflammation had a limited extent in our patient; severe hypertension causing cardiomyopathy and multi-organ damage, not diagnosed before, was primarily responsible for severe illness. Correct diagnosis and guidelines-directed treatment allowed a favorable course.

Assessment of viability

Ischaemic left ventricular (LV) dysfunction due to coronary artery disease (CAD) is steadily increasing as a consequence of the ageing of the population and of improved survival of patients with acute coronary syndromes and currently represents the first cause of heart failure (HF). Myocardial function is dependent on blood supply, as anaerobic reserve is minimum due to a nearly maximal arteriovenous oxygen extraction. At rest, myocardial blood flow remains normal even in the presence of severe coronary artery stenosis (up to 85% diameter stenosis) by coronary autoregulation. In the presence of transstenotic pressure gradient due to epicardial coronary stenosis, arteriolar dilatation maintains normal myocardial flow at rest but with a progressive reduction in flow reserve. When arteriolar dilatation is maximal, autoregulation is exhausted and myocardial ischaemia develops. The limit of autoregulation depends on myocardial oxygen demand and is influenced by heart rate. Tachycardia increases oxygen demand and supply is reduced because of a decreased diastolic perfusion time. In the presence of acute ischaemia, there is a close relation between subendocardial perfusion and transmural function. Indeed, the contribution of subendocardium to myocardial thickening largely exceeds the contribution of the subepicardium. Akinesia can therefore result from subendocardial ischaemia and transmural ischaemia is not necessary. This chapter looks at how viability of the different techniques for treating myocardial dysfunction is assessed.

Multisystem Myotilinopathy, including Myopathy and Left Ventricular Noncompaction, due to the MYOT Variant c.179C>T

Left ventricular hypertrabeculation/noncompaction is a myocardial abnormality of unknown etiology/pathogenesis, which is frequently associated with neuromuscular disorders or chromosomal defects. LVHT in association with a MYOT mutation has not been reported. The patient is a 72-year-old male with a history of strabismus in childhood, asymptomatic creatine-kinase elevation since age 42 years, slowly progressive lower limb weakness since age 60 years, slowly progressive dysarthria and dysphagia since age 62 years, and recurrent episodes of arthralgias and myalgias since age 71 years. He also had arterial hypertension, diverticulosis, hyperlipidemia, coronary heart disease, and a hiatal hernia with reflux esophagitis. Clinical exam revealed mild quadruparesis and proximal wasting of the legs. Whole exome sequencing revealed a known variant in the MYOT gene. Muscle biopsy, previously assessed as inclusion body myopathy, was compatible with the genotype after revision. Cardiologic work-up revealed a left anterior hemiblock, mild myocardial thickening, and noncompaction. This case shows that myotilinopathy may manifest as a multisystem disease, including noncompaction.

Epidemiological and pathological aspects of cardiomyopathies in cats in southern Brazil

ABSTRACT: Cardiomyopathies are considered one of the most important causes of heart failure in cats and are subdivided into three main morphological types: hypertrophic (HCM), dilated (DCM), and restrictive (RCM). This study aimed to determine the frequency and types of cardiomyopathies in cats diagnosed in southern Brazil, with an emphasis on their epidemiological and pathological aspects. Necropsy reports filed in a veterinary pathology laboratory were reviewed, and cats diagnosed with cardiomyopathy were selected for the study. Animal identification data, history and clinical signs, and gross lesions, were reviewed and compiled. During the study period, 1.594 cat necropsies were performed, of which 72 (4.5%) comprised a diagnosis of cardiomyopathy. HCM was the most frequent followed by CMR and CMD, representing 77.8%, 12.5% and 9.7%, respectively. Age ranged from three months to 18 years, with a median age of seven years. In relation to sex, 62.5% were males and 37.5% females. In 76.4% of the cases, it affected cats without a breed defined. Restrictive mixed dyspnea and hydrothorax were the main signs or findings of the clinical examination. Sudden death and acute paresis of the pelvic limbs due to aortic thromboembolism have also been described. In HCM, myocardial thickening was observed, with a reduction in the ventricular chamber. Hypertrophy, disarray, and fibrosis of the myofibers were the main histological findings. In RCM, whitish and thickened endocardium was seen in most cases. DCM was characterized by dilated cardiac chambers, and microscopic examination revealed no significant findings. The main extra cardiac lesions revealed pulmonary edema and congestion, hydrothorax and chronic passive congestion of the liver. Cardiomyopathies are important causes of death in cats and should be included in the differential diagnosis of patients with cardio respiratory clinical signs and in cases related to sudden death and acute paresis of the pelvic limbs.

THE FEATURES OF MYOCARDIAL HEMODYNAMIC AND VEGETATIVE HOMEOSTASIS IN ATHLETES OF DIFFERENT QUALIFICATIONS FROM ACYCLIC SPORTS

Aim. The article deals with studying the functional status of the cardiovascular system and the features of its regulation in athletes of different qualifications from acyclic sports. Materials and methods. Male athletes of different qualifications aged 18–22 years and involved in acyclic sports participated in the study. A complex noninvasive bioimpedance study of HRV and hemodynamics was conducted with the Centaur (Microlux) system. The study of morphofunctional indicators of the myocardium was performed with echocardiography. Results. In athletes with the rank of Master of Sports adaptation to physical training is implemented through the increase in stroke volume, end-diastolic volume, end-systolic volume, the humoral metabolic activity of heart rate regulation, and myocardial thickening. In the athletes of the 1st and 2nd ranks, there is a predominance of sympathetic activity in heart rate regulation and the chronotropic mechanism in response to physical load, which proves their less perfect adaptation. Conclusion. Based on the results obtained in the transition period of training the features of myocardial hemodynamic and vegetative homeostasis were revealed. Namely, the increase in qualifications and sports performance enhancement are determined by both morphofunctional changes in the heart, and the improvement of heart rate regulation mechanisms and cardiac contractile function.

Stress Cardiac Magnetic Resonance Imaging

The chapter Stress Cardiac Magnetic Resonance Imaging reviews how cardiovascular magnetic resonance imaging (CMR) has become a gold standard for evaluating stress induced wall motion abnormalities based on regional endocardial excursion and myocardial thickening. The high spatial and temporal resolution of CMR without limitations imposed by body habitus and acoustic windows allows outstanding visualization of myocardial function. CMR can also be combined with vasodilator stress to perform dynamic first-pass myocardial perfusion imaging. The addition of late gadolinium enhancement allows the accurate of nonviable scar tissue in combination with wall motion and myocardial perfusion assessment. Case studies highlight the opportunity provided by stress CMR.