due to cardiovascular risks. According to him

"Cardiac complications are common in patients requiring hospitalization, and may occur late, and are an alarming cause of mortality. Etiology unclear, direct viral myocarditis, vs. plaque rupture from inflammatory state, vs. demand (Type II) MI from decreased coronary flow, vs. somehow related to virus attaching to ACE2 receptor. But somewhere between 19.7 and 27.8% of COVID patients develop elevated troponins, and if no underlying CVD increases mortality to 37.5%, and if underlying CVD to 69.4%. Malignant deadly arrhythmias common cause of death (up to 44% of all ICU patients develop some arrhymia), as is sudden unrelenting cardiogenic shock. Cardiac complications may develop very late in course, when respiratory status improving."

He has stated that Hydroxychloroquine will increase risks of cardiac events. Don't know if true but that was his reasoning.