- Joined
- Apr 22, 2007
- Messages
- 22,315
- Reaction score
- 8,963
Choice of medications — The choice of medications in patients with DHF is determined by two factors:
●Treatment of specific underlying processes such as hypertension or symptomatic coronary heart disease (CHD). Combined therapy may be warranted since hypertrophied hearts are more sensitive to the deleterious effects of ischemia on left ventricular (LV) relaxation than nonhypertrophied hearts [12]. (See "Pathophysiology of diastolic heart failure".)
●The possibly beneficial effect of the drug on the pathophysiology of DHF
An important caveat is that the patient who has LV diastolic dysfunction with a small, stiff LV chamber is particularly susceptible to excessive preload reduction, which can lead to underfilling of the LV, a fall in cardiac output, and hypotension. In patients with severe LV hypertrophy (LVH) due to hypertension or hypertrophic cardiomyopathy, excessive preload reduction can also create subaortic outflow obstruction.
For these reasons, diuretics or venodilators such as nitrates and dihydropyridine calcium channel blockers must be administered with caution. Careful attention is required for symptoms of ventricular underfilling such as weakness, dizziness, near syncope, and syncope.
Digoxin is generally not used in patients with DHF because systolic function is intact. The DIG ancillary trial, a parallel study to the DIG trial, evaluated the role of digoxin in patients with HF and a LV ejection fraction (LVEF) >45 percent [13,14]. At a mean follow-up of 37 months, digoxin had no effect on all-cause or cause-specific mortality, or all-cause or cardiovascular hospitalization [13]. (See "Use of digoxin in heart failure due to systolic dysfunction".)
Antihypertensive therapy — Lowering the systemic blood pressure was associated with reduced rate of HF in some large randomized hypertension treatment trials, particularly those including diuretic therapy [15,16]. The choice of a specific antihypertensive agent must be individualized in the presence of coexisting diseases such as diabetes mellitus or chronic obstructive pulmonary disease. (See "Choice of drug therapy in primary (essential) hypertension: Recommendations".)
Regression of LVH is an important therapeutic goal, since it may improve diastolic function [17]. A meta-analysis published in 2003 attempted to evaluate the relative efficacy of different antihypertensive drugs for their ability to reverse LVH in patients with hypertension [18]. Eighty trials that included 146 and 17 active treatment and placebo arms, respectively, were evaluated. After statistical adjustments for length of therapy and degree of blood pressure lowering, the relative reductions in LV mass index were (figure 1):
●Angiotensin II receptor blockers (ARBs) - 13 percent
●Calcium channel blockers - 11 percent
●Angiotensin converting enzyme (ACE) inhibitors - 10 percent
●Diuretics - 8 percent
●Beta blockers - 6 percent
It appears that ARBs, calcium channel blockers, and ACE inhibitors produced more regression than beta blockers. The clinical significance of this difference is uncertain since there is as yet no evidence that more rapid regression of LVH is associated with improved long-term outcomes. The choice of antihypertensive therapy is usually based upon other factors.
●Treatment of specific underlying processes such as hypertension or symptomatic coronary heart disease (CHD). Combined therapy may be warranted since hypertrophied hearts are more sensitive to the deleterious effects of ischemia on left ventricular (LV) relaxation than nonhypertrophied hearts [12]. (See "Pathophysiology of diastolic heart failure".)
●The possibly beneficial effect of the drug on the pathophysiology of DHF
An important caveat is that the patient who has LV diastolic dysfunction with a small, stiff LV chamber is particularly susceptible to excessive preload reduction, which can lead to underfilling of the LV, a fall in cardiac output, and hypotension. In patients with severe LV hypertrophy (LVH) due to hypertension or hypertrophic cardiomyopathy, excessive preload reduction can also create subaortic outflow obstruction.
For these reasons, diuretics or venodilators such as nitrates and dihydropyridine calcium channel blockers must be administered with caution. Careful attention is required for symptoms of ventricular underfilling such as weakness, dizziness, near syncope, and syncope.
Digoxin is generally not used in patients with DHF because systolic function is intact. The DIG ancillary trial, a parallel study to the DIG trial, evaluated the role of digoxin in patients with HF and a LV ejection fraction (LVEF) >45 percent [13,14]. At a mean follow-up of 37 months, digoxin had no effect on all-cause or cause-specific mortality, or all-cause or cardiovascular hospitalization [13]. (See "Use of digoxin in heart failure due to systolic dysfunction".)
Antihypertensive therapy — Lowering the systemic blood pressure was associated with reduced rate of HF in some large randomized hypertension treatment trials, particularly those including diuretic therapy [15,16]. The choice of a specific antihypertensive agent must be individualized in the presence of coexisting diseases such as diabetes mellitus or chronic obstructive pulmonary disease. (See "Choice of drug therapy in primary (essential) hypertension: Recommendations".)
Regression of LVH is an important therapeutic goal, since it may improve diastolic function [17]. A meta-analysis published in 2003 attempted to evaluate the relative efficacy of different antihypertensive drugs for their ability to reverse LVH in patients with hypertension [18]. Eighty trials that included 146 and 17 active treatment and placebo arms, respectively, were evaluated. After statistical adjustments for length of therapy and degree of blood pressure lowering, the relative reductions in LV mass index were (figure 1):
●Angiotensin II receptor blockers (ARBs) - 13 percent
●Calcium channel blockers - 11 percent
●Angiotensin converting enzyme (ACE) inhibitors - 10 percent
●Diuretics - 8 percent
●Beta blockers - 6 percent
It appears that ARBs, calcium channel blockers, and ACE inhibitors produced more regression than beta blockers. The clinical significance of this difference is uncertain since there is as yet no evidence that more rapid regression of LVH is associated with improved long-term outcomes. The choice of antihypertensive therapy is usually based upon other factors.
