Long-Lasting Myocardial and Skeletal Muscle Damage Evidenced by Serial CMR During the First Year in COVID-19 Patients From the First Wave.

Introduction: This observational CMR study aims to characterize left-ventricular (LV) damage, which may be specifically attributed to COVID-19 and is distant in time from the acute phase, through serial CMR performed during the first year in patients with no prior cardiac disease. Methods: This study included consecutive patients without any prior history of cardiac disease but with a peak troponin-Ic > 50 ng/ml at the time of the first COVID-wave. All had a CMR in the first months after the acute phase, and some had an additional CMR at the end of the first year to monitor LV function, remodeling, and abnormalities evocative of myositis and myocarditis - i.e., increased T1/T2 relaxation times, increased extracellular volume (ECV), and delayed contrast enhancement. Results: Nineteen consecutively admitted COVID-19 patients (17 men, median age 66 [57-71] years) were included. Eight (42%) had hypertension, six (32%) were obese, and 16 (84%) had suffered an acute respiratory distress syndrome. The 1st CMR, recorded at a median 3.2 [interquartile range: 2.6-3.9] months from the troponin peak, showed (1) LV concentric remodeling in 12 patients (63%), (2) myocardial tissue abnormalities in 11 (58%), including 9 increased myocardial ECVs, and (3) 14 (74%) increased ECVs from shoulder skeletal muscles. The 2nd CMR, obtained at 11.1 [11.0-11.7] months from the troponin peak in 13 patients, showed unchanged LV function and remodeling but a return to normal or below the normal range for all ECVs of the myocardium and skeletal muscles. Conclusion: Many patients with no history of cardiac disease but for whom an increase in blood troponin-Ic ascertained COVID-19 induced myocardial damage exhibited signs of persistent extracellular edema at a median 3-months from the troponin peak, affecting the myocardium and skeletal muscles, which resolved within a one-year time frame. Associations with long-COVID symptoms need to be investigated on a larger scale now. Clinical Trial Registration: NCT04753762 on the ClinicalTrials.gov site.

Acute Hyperglycemia Does Not Affect Brain Swelling or Infarction Volume After Middle Cerebral Artery Occlusion in Rats.

Stroke disproportionally affects diabetic and hyperglycemic patients with increased incidence and is associated with higher morbidity and mortality due to brain swelling. In this study, the intraluminal suture middle cerebral artery occlusion (MCAO) model was used to examine the effects of blood glucose on brain swelling and infarct volume in acutely hyperglycemic rats and normo-glycemic controls. Fifty-four rats were distributed into normo-glycemic sham surgery, hyperglycemic sham surgery, normo-glycemic MCAO, and hyperglycemic MCAO. To induce hyperglycemia, 15 min before MCAO surgery, animals were injected with 50 % dextrose. Animals were subjected to 90 min of MCAO and sacrificed 24 h after reperfusion for hemispheric brain swelling and infarct volume calculations using standard equations. While normo-glycemic and hyperglycemic animals after MCAO presented with significantly higher brain swelling and larger infarcts than their respective controls, no statistical difference was observed for either brain swelling or infarct volume between normo-glycemic shams and hyperglycemic shams or normo-glycemic MCAO animals and hyperglycemic MCAO animals. The findings of this study suggest that blood glucose does not have any significant effect on hemispheric brain swelling or infarct volume after MCAO in rats.

Correlation Between Subacute Sensorimotor Deficits and Brain Edema in Rats after Surgical Brain Injury.

No matter how carefully a neurosurgical procedure is performed, it is intrinsically linked to postoperative deficits resulting in delayed healing caused by direct trauma, hemorrhage, and brain edema, termed surgical brain injury (SBI). Cerebral edema occurs several hours after SBI and is a major contributor to patient morbidity, resulting in increased postoperative care. Currently, the correlation between functional recovery and brain edema after SBI remains unknown. Here we examine the correlation between neurological function and brain water content in rats 42 h after SBI. SBI was induced in male Sprague-Dawley rats via frontal lobectomy. Twenty-four hours post-ictus animals were subjected to four neurobehavior tests: composite Garcia neuroscore, beam walking test, corner turn test, and beam balance test. Animals were then sacrificed for right-frontal brain water content measurement via the wet-dry method. Right-frontal lobe brain water content was found to significantly correlate with neurobehavioral deficits in the corner turn and beam balance tests: the number of left turns (percentage of total turns) for the corner turn test and distance traveled for the beam balance test were both inversely proportional with brain water content. No correlation was observed for the composite Garcia neuroscore or the beam walking test.