Novocain sometimes doesn't interact very well with other mediations. Did the dentist know of any medications you may have been taking. Also, side effects can be reduced if the dentist takes into consideration the patient's size to prevent too much of a dosage. Your doctor is correct, but the "sometimes" may be dosage related.
Side of effects is drowsiness, trouble breathing resulting in respiratory failure, tremors of the extremities, dizziness, headache and unconsciousness. If a patient has a history of heart failure, the respiratory failure can be very serious conditon as related to the heart. If you didn't have a heart problem as ed states there probably wasn't any damage to the heart muscles (hypoxia).
An EKG is not a reliable source to diagnose a prior heart attack. The output of the EKG is elevation of the ST segment of a heart beat, and there are a number of other insignificant causes such as electrolytic imbalance, medication, etc. And always a positive EKG test requires other tests and supporting symptoms.
Several years ago, I was shocked to learn I had had a prior attack and didn't have the usual symptoms. A stress test or echocardiogram is the appropriate followup tests. Good luck! Thanks for sharing, and if you have any followup questions you are welcome to respond.
It sounds like you had an adrenaline rush. A chemical in the local anaesthetic called epinephrine which is the same as adrenaline you find in your blood stream. The reason it's added is to make the anaesthetic more efficient and last longer. If the anaesthetic is injected into a blood vessel, the chemical will be received by the heart and your body will go into a mode of fight or flight. Your heart rate will increase, breathing will increase and you may shake and sweat. All unexpectedly, so anxiety will add to this.
I doubt if the episode would have cause MI, unless your heart was seriously defecit in oxygen to cope with the stress. Your heart rate will be increase during the nuclear testing, and if you are unable to increase your rate enough with a treadmill, they will chemically induce stress to the heart. I recommend you relax and avoid anxiety if they do this, just relax and take deep breaths. It only lasts around 30 seconds and although not the nicest thing in the world, it soon passes. Even people with healthy hearts can feel symptoms during this phase.