ACE inhibitor


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Related to ACE inhibitor: Angiotensin receptor blocker, Beta blockers

ACE inhibitor

A class of drugs (angiotensin-converting enzyme inhibitors) that block the conversion of angiotensin I to angiotensin II, used in the treatment of hypertension and congestive heart failure and in the prevention of microvascular complications of diabetes mellitus (DM).

The renin-angiotensin system is involved in the regulation of blood pressure and electrolyte balance. Angiotensinogen, a globulin formed in the liver, is converted to angiotensin I by renin, an enzyme produced by the juxtaglomerular cells of renal afferent arterioles. Renin release can be triggered by a drop in systemic blood pressure (either directly through baroreceptors or indirectly through reduction in renal tubular fluid, as in hypotension or dehydration) or in serum sodium chloride concentration. Angiotensin I is converted by the ACE, a glycoprotein produced chiefly in the lung, to angiotensin II. (ACE also degrades bradykinin, a vasodilator.) Angiotensin II is a potent vasoconstrictor and neurotransmitter, which raises peripheral vascular resistance and induces sodium retention by stimulating the adrenal cortex to secrete aldosterone. In addition, angiotensin II stimulates cell migration and the growth and proliferation of vascular smooth muscle. Because it plays a pivotal role in the pathogenesis of essential hypertension, congestive heart failure, and diabetic nephropathy, drugs that block production of angiotensin II are useful in those disorders. ACE inhibitors have an established place in the treatment of essential hypertension, congestive heart failure, and left ventricular dysfunction after myocardial infarction. Their effectiveness in hypertension is less marked in black patients than in nonblacks. ACE inhibitors may lessen cardiovascular risk by improving endothelial dysfunction, reducing inflammation, and promoting fibrinolysis by inhibiting plasminogen activator inhibitor-1. The protection afforded by these agents against vascular complications of DM is independent of their effect on blood pressure. They can slow the progression of diabetic nephropathy in patients with Type 1 DM, and of microalbuminuria in those with Type 2 DM, even in the absence of hypertension. Studies have shown a 50% reduction in the risk of the combined end-points of death, dialysis, and renal transplantation in patients with Type 1 DM who were treated with the ACE inhibitor captopril. In addition, ACE inhibitors may prevent development of DM in nondiabetic hypertensive patients. Their potentiation of the effects of bradykinin may account for their ability to enhance insulin sensitivity and may explain their apparent benefit in preventing new-onset Type 2 DM. The usefulness of these agents is limited by their tendency to elevate levels of blood urea nitrogen and creatinine, particularly in conjunction with diuretic therapy and in patients with renal disease or congestive heart failure, and to cause nonproductive cough.

Farlex Partner Medical Dictionary © Farlex 2012

ACE inhibitor

(ās)
n.
Any of a class of drugs that cause vasodilation and are used to treat hypertension and heart failure.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.

ACE inhibitor

Angiotensin-converting enzyme inhibitor. Any of a family of drugs used to manage hypertension and reduce congestive heart failure (CHF)-related mortality and morbidity.

Examples
Bepridil, captopril, enalapril, lisionopril, losartan, quinapril, ramipril.

ACE inhibitor Effects in Heart Disease
Cardioprotective effects
• Restores balance between myocardial O2 supply and demand;
• Reduces left ventricular preload and afterload;
• Reduces left ventricular mass;
• Reduces sympathetic stimulation.
Vasculoprotective effects
• Antiproliferative and antimigratory effects on smooth muscle and inflammatory cells;
• Antiplatelet effects;
• Improved arterial compliance and tone;
• Improved and/or restored endothelial function;
• Antihypertensive;
• Possible antiatherosclerotic effect. 

Pros
ACEIs are cardioprotective and vasculoprotective; cardioprotective effects include improved haemodynamics and electric stability, reduce sympathetic nervous system (SNS) activity and reduce left ventricular mass; vasculoprotective benefits include improved endothelial function, vascular compliance and tone, and direct antiproliferative and antiplatelet effects. ACEIs also stimulate prostaglandin (PG) synthesis, reduce the size of MIs, and reduce reperfusion injury and complex ventricular arrhythmias.

ACEIs are the treatment of choice in CHF with systolic dysfunction; they are vasodilators which decrease preload and afterload. ACEI-induced reduction in angiotensin II inhibits the release of aldosterone, which in turn reduces sodium and water retention which, by extension, reduce preload; ACEIs improve haemodynamics of CHF by reducing right atrial pressure, pulmonary capillary wedge pressure, arterial BP, as well as pulmonary and systemic vascular resistance; ACEIs increase cardiac and stroke indices by the left ventricle and reduce the right ventricular end-diastolic volumes, thereby increasing cardiac output, while simultaneously reducing cardiac load and myocardial O2 consumption.
 
Adverse effects
• Idiopathic—e.g., rashes, dysgeusia, BMsuppression.
• Class-specific—e.g., hypotension, renal impairment, hyperkaleamia, cough, angioneurotic oedema (the latter 2 of which are mediated by small vasoactive substances—e.g., bradykinin, substance P, and PG-related factors).
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.

ACE inhibitor

Angiotensin-converting enzyme inhibitor Pharmacology Any of a family of drugs that are used to manage essential HTN, ↓ CHF-related M&M  Pros ACEIs are cardioprotective and vasculoprotective; cardioprotective effects include improved hemodynamics and electric stability, ↓ SNS activity and ↓ left ventricular mass; vasculoprotective benefits include improved endothelial function, vascular compliance and tone, and direct antiproliferative and antiplatelet effects; ACEIs also stimulate PG synthesis, ↓ the size of MIs, ↓ reperfusion injury and complex ventricular arrhythmias; ACEIs are the treatment of choice in CHF with systolic dysfunction; they are vasodilators which ↓ preload and afterload; ACEI-induced ↓ in angiotensin II inhibits the release of aldosterone, which in turn ↓ sodium and water retention which, by extension, ↓ preload; ACEIs improve hemodynamics of CHF by ↓ right atrial pressure, pulmonary capillary wedge pressure, arterial BP, as well as pulmonary and systemic vascular resistances; ACEIs ↑ cardiac and stroke indices by the left ventricle and ↓ the right ventricular end-diastolic volumes, thereby resulting in ↑ cardiac output, while simultaneously ↓ cardiac load and myocardial O2 consumption; ACEIs also downregulate the SNS, which is linked to the pathogenesis of CHF Adverse effects Idiopathic–eg, rashes, dysgeusia, BM suppression; class-specific–eg, hypotension, renal impairment, hyperkalemia, cough, angioneurotic edema, the latter 2 of which are mediated by small vasoactive substances, eg, bradykinin, substance P, and PG-related factors

ACE inhibitor Effects in Heart Disease

Cardioprotective effects
  • Restores balance between myocardial O2 supply & demand
  • Reduces left ventricular preload and afterload
  • Reduces left ventricular mass
  • Reduces sympathetic stimulation
Vasculoprotective effects
  • Antiproliferative & antimigratory effects on smooth muscle & inflammatory cells
  • Antiplatelet effects
  • Improved arterial compliance and tone
  • Improved and or restored endothelial function
  • Antihypertensive
  • Possibly, antiatherosclerotic effect
After Lonn et al, 1994
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.

Angiotensin-converting enzyme (ACE) inhibitor

A drug that relaxes blood vessel walls and lowers blood pressure.
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.

ACE in·hi·bi·tor

(ās in-hibi-tŏr)
Class of drugs (angiotensin-converting enzyme inhibitors) that blocks conversion of angiotensin I to angiotensin II; used to treat hypertension and other disorders.
Medical Dictionary for the Dental Professions © Farlex 2012
References in periodicals archive ?
The drug should not be used at the same time as an ACE inhibitor or ARB.
Patients taking an ACE inhibitor have an increased risk of cough (6 studies; 11,791 patients; RR=1.84; 95% CI, 1.24-2.72).
A few cases of angioedema following local trauma in patients using ACE inhibitors have been published [3-7].
"More studies are needed to further investigate the relationship between the kidney protective effects of ACE inhibitors and the impact cigarette smoking may have on these effects."
In a literature review by Strauss (1996), three major reactions from TPEs were analyzed from previous research studies: citrate reactions, hypovolemia and vasovagal reactions, and ACE inhibitor reactions.
ACE inhibitor 0.38 points Antihypertensive other than Ace inhibitor 0.64 points Note: Based on a study of 1,074 hypertensive patients followed for a median of 6 years.
One hundred and seventy-six (57%) patients were discharged from hospital with an ACE inhibitor prescription (98 on captopril, 53 on enalapril, 20 on lisinopril, two each on perindopril and fosinopril and one on ramipril).
* Ask your doctor whether you might benefit from receiving an ACE inhibitor.
For patients not suited to treatment with an ARNI, continued use of an ACE inhibitor is recommended.
ACE inhibitors were not found more likely than other antihypertensive drugs to be associated with an increase in congenital heart defects when used in the first trimester only.
The researchers looked at 32 312 seniors in Alberta, Canada, aged 65 and older who were prescribed an ACE inhibitor and/or an ARB.