[SARS-COV-2 myocarditis. An update]. / Myocardite et maladie à COVID-19 : où en est-on ?

The outbreak of the SARS-CoV-2 virus responsible for the COVID-19 disease has given rise to a new disease whose boundaries are still to be discovered. While the first data suggested a purely respiratory infection, the most recent publications highlight a large pleomorphism of the disease, responsible for multiple organ damage, of which cardiac injury seems to be the most represented. This cardiac injury can present as acute myocarditis. Our aim was to discuss the pathophysiological rationale underlying the existence of SARS-CoV-2 myocarditis and to analyze the literature data regarding the diagnosis and treatment of this particular entity.

High water intake combined with low sodium intake abolishes the antidiuretic effect of angiotensin II in conscious dogs.

1. We studied post-prandial changes in renal function in dogs adapted to either low or high sodium intake with and without concomitant post-prandial infusion of angiotensin II. Six trained dogs were exposed to diets containing either 0.5 or 14.5 mmol Na+ day-1 kg-1 body weight (low or high sodium respectively). They were studied from 20 min before to 4 h after food intake. In half of the experiments a physiological dose of angiotensin II (4 ng min-1 kg-1 body weight) was administered after food intake for four post-prandial hours. The water intake was high and equal on both diets (91 ml day-1 kg-1 body weight). 2. On a high-salt diet post-prandial sodium excretion and urine volume increased considerably above fasting values. This post-prandial increase was attenuated when angiotensin II was infused (post-prandial sodium excretion was 31% +/- 3% of intake without versus 10% +/- 1% with angiotensin II, post-prandial urine volume was 22% +/- 2% without versus 8% +/- 1% with angiotensin II, P < 0.05). Post-prandial increases in glomerular filtration rate and fractional sodium excretion were attenuated during angiotensin II infusion in dogs on a high-salt diet. 3. On a low-salt diet post-prandial sodium excretion remained low with or without angiotensin II infusion, whereas urine volume increased post-prandially, and this increase was greater when angiotensin II was administered (40% +/- 3% versus 34% +/- 2% of intake, P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)