HEART INFLAMMATION; HEART ATTACK TRIGGERED BRONCHITIS; OXYGEN PLUMMETED TO 60 PERCENT; HEART ATTACK; DEHYDRATION; VOMITING; DIARRHEA; BP WENT TO 88/50 OR 88/60; This spontaneous report received from a patient concerned a patient of unspecified age and sex. The patient's height, and weight were not reported. The patient's concurrent condition included: overweight (10-15 pounds overweight). The patient was in excellent health with no pre-existing health issues, nor medication, prior to the vaccine. The patient received covid-19 vaccine ad26.cov2.s (suspension for injection, route of admin not reported, batch number: 205A21A, expiry: UNKNOWN) dose was not reported, 1 total, administered on 31-JUL-2021 for prophylactic vaccination. No concomitant medications were reported.  Just after the vaccine was taken, the patient went to urgent care and emergency room (ER) several times for dehydration, caused by vomiting and diarrhea. The first urgent care visit was 02-AUG-2021. On 03-AUG-2021, the patient was in another emergency room. On 06-AUG-2021, the patient went back to urgent care and again on 08-AUG-2021, where patient's blood pressure (BP) went to 88/50 or 88/60. On 09-AUG-2021, the patient had a heart attack, which doctors attributed to the JNJ vaccine. The patient was hospitalized on an unspecified date. The patient was left with heart inflammation, which would pass in late NOV-2021 or early DEC-2021 according to Cardiologist. The heart attack triggered bronchitis and the patient was at the tail end of that. The oxygen plummeted to 60 percent in the emergency room of hospital out of nowhere. The patient was peacefully getting intravenous fluids there and suddenly could not breathe at all. About 2 minutes passed with 60 percent oxygen, where the patient was about to die. Very fortunately, after the patient opened the green curtain in front, the emergency room doctor was standing there right in front and saved patient's life, with many nurses running to patient. The only reason the patient was alive was that the patient went to the ER with no wait and the ER doctor was standing next to patient behind the green curtain. If the ER doctor was down the hall, the patient would have died as patient was told or if patient would have gone to another hospital, which had a very long wait, the patient would have died in the waiting room most likely. The patient was ended up getting stabilized and admitted then taken by ambulance to another hospital at midnight. The patient spent 5 days in the Cardiac Unit there. The CT scan of heart with contrast revealed that vaccine caused the heart attack and oxygen to drop to 60 percent from normal 98-99 percent level. The patient also ended up medical care clinic 2 days after hospital discharge also for several breathing issues and bronchitis. The patient had not recovered from heart inflammation, and the outcome of heart attack, dehydration, heart attack triggered bronchitis, vomiting, diarrhea, BP went to 88/50 or 88/60 and oxygen plummeted to 60 percent was not reported. This report was serious (Hospitalization Caused / Prolonged, and Other Medically Important Condition). This case, from the same reporter is linked to 20210923692.; Sender's Comments: V0-20210921562-Covid-19 vaccine ad26.cov2.s- Heart attack, heart inflammation,heart attack triggered bronchitis,oxygen plummeted to 60 percent, BP went to 88/50 or 88/60 .This event(s) is considered unassessable. The event(s) has an compatible/suggestive temporal relationship, is unlabeled, and has unknown scientific plausibility. There is no information on any other factors potentially associated with the event(s).