Does quitting smoking bring on episodes of svt?

No. Smoking increases your risk of paroxysmal supraventricular tachycardia, or psvt (sudden-onset svt). Quitting smoking would decrease your risk for most smoking-related conditions gradually, so you will still be at risk for a while after you quit. Drugs, caffeine, alcohol, and abnormal pathways in the heart's conductive tissue (ie. Bundle of kent) can also predispose you to svt.
If it causes stress. Smoking cessation can be stressful, with increased anxiety, and often high levels of our stress hormones like dopamine, serotonin, adrenaline etc. These stress hormones may precipitate an episode of svt in predisposed individuals, but I have not had a patient without such predisposition get svt while trying to stop smoking. If you are having svt, see your doctor for treatment, but keep on quitting.