Blood clots; felt he was having a heart attack; He lost control of his ability to walk; Became Worse; He lives a sad limited life; Angry; Purple like having a blood clot; Pain; Completely ill/sick; Weaker Heart; This spontaneous case was reported by a consumer and describes the occurrence of THROMBOSIS (Blood clots) and MYOCARDIAL INFARCTION (felt he was having a heart attack) in an 85-year-old male patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch no. 026L20A) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     Concurrent medical conditions included Cancer (Was on Chemotherapy and radiation treatment), Handicap, Penicillin allergy, Sulfonamide allergy (Sulfa) and Drug allergy (Morphine). Concomitant products included APIXABAN, FUROSEMIDE and METOPROLOL TARTRATE for an unknown indication.    On 08-Jan-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 10-Feb-2021, the patient experienced THROMBOSIS (Blood clots) (seriousness criteria hospitalization and medically significant), MYOCARDIAL INFARCTION (felt he was having a heart attack) (seriousness criteria hospitalization and medically significant), CARDIAC DISORDER (Weaker Heart), VACCINATION COMPLICATION (Completely ill/sick) and VACCINATION SITE PAIN (Pain). On an unknown date, the patient experienced GAIT DISTURBANCE (He lost control of his ability to walk), CONDITION AGGRAVATED (Became Worse), DEPRESSED MOOD (He lives a sad limited life), ANGER (Angry) and VACCINATION SITE ERYTHEMA (Purple like having a blood clot). The patient was hospitalized from 17-Feb-2021 to 26-Feb-2021 due to MYOCARDIAL INFARCTION and THROMBOSIS. At the time of the report, THROMBOSIS (Blood clots), MYOCARDIAL INFARCTION (felt he was having a heart attack), CARDIAC DISORDER (Weaker Heart), GAIT DISTURBANCE (He lost control of his ability to walk), CONDITION AGGRAVATED (Became Worse), VACCINATION COMPLICATION (Completely ill/sick), DEPRESSED MOOD (He lives a sad limited life), ANGER (Angry), VACCINATION SITE ERYTHEMA (Purple like having a blood clot) and VACCINATION SITE PAIN (Pain) outcome was unknown.        The action taken with mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) was unknown.       The first dose of Moderna vaccine reportedly given on 08 Jan 2021.  The patient's wife reported that he would not take the second shot.  However, it was reported that patient's events started 10 Feb 2021, 2 days after vaccination.  Therefore, the date of first dose and whether patient received second dose (and if he did, on what date) are unclear.  Patient has received home therapy.  Patient stated that on 22 Jun 2021 his health was failing daily and he had radiation from his cancer treatments in his body when the shot was given.  It was felt the shot had taken his health to a point of no return - "bad call on the people who set him up for the shot and did not screen his health ".    Based on the current available information and temporal association between the use of the product and the start date of the events, a causal relationship cannot be excluded.   Most recent FOLLOW-UP information incorporated above includes: On 22-Jun-2021: Patient details, medical history, and suspect product details were updated. Events and concomitant medications were added.  Case upgraded to serious.; Sender's Comments: Based on the current available information and temporal association between the use of the product and the start date of the events, a causal relationship cannot be excluded.