Ans. is 'd' i.e., Pheochromocytoma Uses of ACE inhibitor I) Hypeension ? o The antihypeensive effect of ACE inhibitor results primarily from vasodilatation. o A decrease in aldosterone production may also contribute to antihypeensive effect. o ACE inhibitors are now the first line drugs in all grades of hypeension (About 50% of patients respond to monotherapy) o ACE inhibitors are most useful in hypeension when the raised blood pressure results from excess renin production (renovascular hypeension) II) Cardiac failure ? o In hea failure there is excessive activation of renin angiotensin aldosterone system. o ACE inhibitors abolish the effect of angiotensin II (vasoconstriction, aldosterone secretion and, Na+ & water retention) by preventing conversion of AT-I to AT-II. o Multicentric trials have shown that ACE inhibitors retard the progression of left ventricular systolic dysfunction and prolong survival of CHF patients of all grades (I to IV) (they reduce moality). o Unless contraindicated ACE inhibitors are now advocated as first line drugs in all patients with symptomatic as well as asymptomatic left ventricular inadequacy. 111) Diabetic nephropathy - o ACE inhibitors have a specific renoprotective effect because Angiotensin II is the main factor responsible for pathological changes. o Prolonged ACE inhibitor therapy has been found to prevent or delay end stage renal disease in type I as well as type II diabetics. o ACE inhibitors are the first line drug for hypeensive type I diabetics. There is also evidence that ACE inhibitors have a proteinuria-sparing effect in type I diabetics with normal B.P. o All patients with diabetic nephropathy, whether hypeensive or normotensive deserve ACE inhibitor therapy. o AT-II antagonists have better renoprotective effect in type 2 DM with nephropathy. IV) Myocardial infarction ? o Following MI, the LVF may occur from the loss of functional tissue or from a process of remodelling of the scarred ventricular wall. o Angiotensin II plays a key role in both these processes. o ACE inhibitors given after M.I. markedly reduce the incidence of hea failure. V) Scleroderma crisis ? o ACE inhibitors cause dramatic improvement in patients of scleroderma crisis with marked rise in B.P. and deterioration in renal function. VI) Prophylaxis in high cardiovascular risk subjects o ACE inhibitors tilt the fibrinolytic balance towards a profibronolytic state by reducing plasma levels of plasminogen activator inhibitor - 1.