Write SQL query to solve given problem: How many of the patients who have stopped taking medication for 'coronary heart disease' are still alive?. Keep the solution inside sql tag ```sql [SQL-Query] ```
SELECT COUNT(DISTINCT T2.patient) FROM medications AS T1 INNER JOIN patients AS T2 ON T1.PATIENT = T2.patient WHERE T1.REASONDESCRIPTION = 'Coronary Heart Disease' AND T1.STOP IS NOT NULL AND T2.deathdate IS NULL