Hydrochlorothiazide is superior to isradipine for reduction of left ventricular mass: results of a multicenter trial. The Isradipine Study Group

Calcium channel blockers versus other classes of drugs for hypertension

BACKGROUND

This is the first update of a review published in 2010. While calcium channel blockers (CCBs) are often recommended as a first-line drug to treat hypertension, the effect of CCBs on the prevention of cardiovascular events, as compared with other antihypertensive drug classes, is still debated.

OBJECTIVES

To determine whether CCBs used as first-line therapy for hypertension are different from other classes of antihypertensive drugs in reducing the incidence of major adverse cardiovascular events.

SEARCH METHODS

For this updated review, the Cochrane Hypertension Information Specialist searched the following databases for randomised controlled trials (RCTs) up to 1 September 2020: the Cochrane Hypertension Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL 2020, Issue 1), Ovid MEDLINE, Ovid Embase, the World Health Organization International Clinical Trials Registry Platform, and ClinicalTrials.gov. We also contacted the authors of relevant papers regarding further published and unpublished work and checked the references of published studies to identify additional trials. The searches had no language restrictions.

SELECTION CRITERIA

Randomised controlled trials comparing first-line CCBs with other antihypertensive classes, with at least 100 randomised hypertensive participants and a follow-up of at least two years.

DATA COLLECTION AND ANALYSIS

Three review authors independently selected the included trials, evaluated the risk of bias, and entered the data for analysis. Any disagreements were resolved through discussion. We contacted study authors for additional information.

MAIN RESULTS

This update contains five new trials. We included a total of 23 RCTs (18 dihydropyridines, 4 non-dihydropyridines, 1 not specified) with 153,849 participants with hypertension. All-cause mortality was not different between first-line CCBs and any other antihypertensive classes. As compared to diuretics, CCBs probably increased  major cardiovascular events (risk ratio (RR) 1.05, 95% confidence interval (CI) 1.00 to 1.09, P = 0.03) and increased congestive heart failure events (RR 1.37, 95% CI 1.25 to 1.51, moderate-certainty evidence). As compared to beta-blockers, CCBs reduced the following outcomes: major cardiovascular events (RR 0.84, 95% CI 0.77 to 0.92), stroke (RR 0.77, 95% CI 0.67 to 0.88, moderate-certainty evidence), and cardiovascular mortality (RR 0.90, 95% CI 0.81 to 0.99, low-certainty evidence). As compared to angiotensin-converting enzyme (ACE) inhibitors, CCBs reduced stroke (RR 0.90, 95% CI 0.81 to 0.99, low-certainty evidence) and increased congestive heart failure (RR 1.16, 95% CI 1.06 to 1.28, low-certainty evidence). As compared to angiotensin receptor blockers (ARBs), CCBs reduced myocardial infarction (RR 0.82, 95% CI 0.72 to 0.94, moderate-certainty evidence) and increased congestive heart failure (RR 1.20, 95% CI 1.06 to 1.36, low-certainty evidence).

AUTHORS' CONCLUSIONS

For the treatment of hypertension, there is moderate certainty evidence that diuretics reduce major cardiovascular events and congestive heart failure more than CCBs. There is low to moderate certainty evidence that CCBs probably reduce major cardiovascular events more than beta-blockers. There is low to moderate certainty evidence that CCBs reduced stroke when compared to angiotensin-converting enzyme (ACE) inhibitors and reduced myocardial infarction when compared to angiotensin receptor blockers (ARBs), but increased congestive heart failure when compared to ACE inhibitors and ARBs. Many of the differences found in the current review are not robust, and further trials might change the conclusions. More well-designed RCTs studying the mortality and morbidity of individuals taking CCBs as compared with other antihypertensive drug classes are needed for patients with different stages of hypertension, different ages, and with different comorbidities such as diabetes.

Calcium channel blockers versus other classes of drugs for hypertension

BACKGROUND

This is the first update of a review published in 2010. While calcium channel blockers (CCBs) are often recommended as a first-line drug to treat hypertension, the effect of CCBs on the prevention of cardiovascular events, as compared with other antihypertensive drug classes, is still debated.

OBJECTIVES

To determine whether CCBs used as first-line therapy for hypertension are different from other classes of antihypertensive drugs in reducing the incidence of major adverse cardiovascular events.

SEARCH METHODS

For this updated review, the Cochrane Hypertension Information Specialist searched the following databases for randomised controlled trials (RCTs) up to 1 September 2020: the Cochrane Hypertension Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL 2020, Issue 1), Ovid MEDLINE, Ovid Embase, the World Health Organization International Clinical Trials Registry Platform, and ClinicalTrials.gov. We also contacted the authors of relevant papers regarding further published and unpublished work and checked the references of published studies to identify additional trials. The searches had no language restrictions.

SELECTION CRITERIA

Randomised controlled trials comparing first-line CCBs with other antihypertensive classes, with at least 100 randomised hypertensive participants and a follow-up of at least two years.

DATA COLLECTION AND ANALYSIS

Three review authors independently selected the included trials, evaluated the risk of bias, and entered the data for analysis. Any disagreements were resolved through discussion. We contacted study authors for additional information.

MAIN RESULTS

This update contains five new trials. We included a total of 23 RCTs (18 dihydropyridines, 4 non-dihydropyridines, 1 not specified) with 153,849 participants with hypertension. All-cause mortality was not different between first-line CCBs and any other antihypertensive classes. As compared to diuretics, CCBs probably increased  major cardiovascular events (risk ratio (RR) 1.05, 95% confidence interval (CI) 1.00 to 1.09, P = 0.03) and increased congestive heart failure events (RR 1.37, 95% CI 1.25 to 1.51, moderate-certainty evidence). As compared to beta-blockers, CCBs reduced the following outcomes: major cardiovascular events (RR 0.84, 95% CI 0.77 to 0.92), stroke (RR 0.77, 95% CI 0.67 to 0.88, moderate-certainty evidence), and cardiovascular mortality (RR 0.90, 95% CI 0.81 to 0.99, low-certainty evidence). As compared to angiotensin-converting enzyme (ACE) inhibitors, CCBs reduced stroke (RR 0.90, 95% CI 0.81 to 0.99, low-certainty evidence) and increased congestive heart failure (RR 1.16, 95% CI 1.06 to 1.28, low-certainty evidence). As compared to angiotensin receptor blockers (ARBs), CCBs reduced myocardial infarction (RR 0.82, 95% CI 0.72 to 0.94, moderate-certainty evidence) and increased congestive heart failure (RR 1.20, 95% CI 1.06 to 1.36, low-certainty evidence).

AUTHORS' CONCLUSIONS

For the treatment of hypertension, there is moderate certainty evidence that diuretics reduce major cardiovascular events and congestive heart failure more than CCBs. There is low to moderate certainty evidence that CCBs probably reduce major cardiovascular events more than beta-blockers. There is low to moderate certainty evidence that CCBs reduced stroke when compared to angiotensin-converting enzyme (ACE) inhibitors and reduced myocardial infarction when compared to angiotensin receptor blockers (ARBs), but increased congestive heart failure when compared to ACE inhibitors and ARBs. Many of the differences found in the current review are not robust, and further trials might change the conclusions. More well-designed RCTs studying the mortality and morbidity of individuals taking CCBs as compared with other antihypertensive drug classes are needed for patients with different stages of hypertension, different ages, and with different comorbidities such as diabetes.

Does the ADMA/DDAH/NO pathway modulate early regression of left ventricular hypertrophy with esmolol?

Hypertensive left ventricular hypertrophy (LVH) is a maladaptive response to chronic pressure overload and a strong independent risk factor for cardiovascular disease. Regression of LVH is associated with improved prognosis. Regression of LVH with antihypertensive therapy (angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, beta-blockers, calcium channel blockers, and diuretics) has been reported, although only after long-term treatment. Asymmetrical dimethylarginine (ADMA), the most potent endogenous NO synthase inhibitor, is emerging as an important cardiovascular risk factor in patients with arterial hypertension and LVH, and dimethylarginine dimethylaminohydrolase (DDAH) is the mechanism that most frequently leads to accumulation of ADMA (plasma ADMA is cleared in small part by renal excretion, although the bulk of ADMA is degraded by DDAH). Left ventricular mass is strongly modulated by the NO system. As an important inhibitor of the bioavailability of NO, ADMA is an underlying mechanism of LVH. Beta-blockers can induce regression of LVH and reduced plasma ADMA levels. Oxidative stress is increased in patients with LVH, and this in turn increases generation of ADMA. In a previous preclinical study of spontaneously hypertensive rats, we found that short-term treatment (48 h) with esmolol reverses early LVH, increases the bioavailability of NO, and improves antioxidant status in plasma. Therefore, we propose that the ADMA/DDAH/NO pathway could modulate early regression of LVH with esmolol.

Cardioprotective Effect of Thiazide-Like Diuretics: A Meta-Analysis

BACKGROUND AND PURPOSE

Thiazide diuretics (TD), including thiazide-type (chlorothiazide and hydrochlorothiazide) and thiazide-like diuretics (indapamide and chlorthalidone), have been used for the treatment of hypertension for more than 5 decades. This meta-analysis aimed to evaluate whether TD, including thiazide-type and thiazide-like diuretics have additional cardioprotective effects.

EXPERIMENTAL APPROACH

We performed a pooled study of 19 randomized clinical trials (RCTs). PubMed and EMBASE databases were searched for RCTs assessing TD treatment in patients with hypertension.

KEY RESULTS

Nineteen RCTs involving 112,113 patients (56,802 in TD; 55,311 in control) were included. The incidence ratio of cardiac events (CVs) was 34.3 vs. 37.8 per 1,000 patient-years in patients randomized to TD and controls, respectively. TD treatment was associated with reductions in the risks of CVs (odds ratio (OR): 0.86, P = 0.007) and heart failure (OR: 0.62, P < 0.001), but not different in stroke (OR: 0.92, P = 0.438) or CHD (OR: 0.95, P = 0.378) between diuretics and controls. Further analysis showed that the observed benefits were mainly confined to thiazide-like diuretic therapy rather than thiazide-type diuretics with a significant reduction in the risk of CVs (OR: 0.78, P < 0.001), heart failure (OR: 0.57, P < 0.001) and stroke (OR: 0.82, P = 0.016).

CONCLUSIONS AND IMPLICATIONS

This study suggests that use of TD in hypertensive patients results in a reduction in the risk of CVs. Moreover, thiazide-like diuretics have greater protective effect against CVs than thiazide-type diuretics, especially on heart failure, suggesting that preferential use of thiazide-like diuretics over thiazide-type diuretics may result in greater cardiovascular benefits in hypertensive patients.

Calcium channel blockers versus other classes of drugs for hypertension

BACKGROUND

Calcium channel blockers (CCBs) are a relatively new antihypertensive class. The effect of first-line CCBs on the prevention of cardiovascular events, as compared with other antihypertensive drug classes, is unknown.

OBJECTIVES

To determine whether CCBs used as first-line therapy for hypertension are different from other first-line drug classes in reducing the incidence of major adverse cardiovascular events.

SEARCH STRATEGY

Electronic searches of the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASEand the WHO-ISH Collaboration Register (up to May 2009) were performed. We also checked the references of published studies to identify additional trials.

SELECTION CRITERIA

Randomized controlled trial (RCT) comparing first-line CCBs with other antihypertensive classes, with at least 100 randomized hypertensive participants and with a follow-up of at least two years.

DATA COLLECTION AND ANALYSIS

Two authors independently selected the included trials, evaluated the risk of bias and entered the data for analysis.

MAIN RESULTS

Eighteen RCTs (14 dihydropyridines, 4 non-dihydropyridines) with a total of 141,807 participants were included. All-cause mortality was not different between first-line CCBs and any other first-line antihypertensive classes. CCBs reduced the following outcomes as compared to beta-blockers: total cardiovascular events (RR 0.84, 95% CI [0.77, 0.92]), stroke (RR 0.77, 95% CI [0.67, 0.88]) and cardiovascular mortality (RR 0.90, 95% CI [0.81, 0.99]). CCBs increased total cardiovascular events (RR 1.05 , 95% CI [1.00, 1.09], p = 0.03) and congestive heart failure events (RR 1.37, 95% CI [1.25, 1.51]) as compared to diuretics. CCBs reduced stroke (RR 0.89, 95% CI [0.80, 0.98]) as compared to ACE inhibitors and reduced stroke (RR 0.85, 95% CI [0.73, 0.99]) and MI (RR 0.83, 95% CI [0.72, 0.96]) as compared to ARBs. CCBs also increased congestive heart failure events as compared to ACE inhibitors (RR 1.16, 95% CI [1.06, 1.27]) and ARBs (RR 1.20, 95% CI [1.06, 1.36]). The other evaluated outcomes were not significantly different.

AUTHORS' CONCLUSIONS

Diuretics are preferred first-line over CCBs to optimize reduction of cardiovascular events. The review does not distinguish between CCBs, ACE inhibitors or ARBs, but does provide evidence supporting the use of CCBs over beta-blockers. Many of the differences found in the current review are not robust and further trials might change the conclusions. More well-designed RCTs studying the mortality and morbidity of patients taking CCBs as compared with other antihypertensive drug classes are needed for patients with different stages of hypertension, different ages, and with different co-morbidities such as diabetes.

Studies on left ventricular hypertrophy regression in arterial hypertension: a clear message for the clinician?

BACKGROUND

Evidence-based medicine should provide clear and unbiased information to clinicians. We conducted an analysis on published randomized trials evaluating the effects of antihypertensive therapy on left ventricular (LV) morphology assessed by echocardiography to investigate (i) the consistency of criteria used for definition of LV hypertrophy (LVH) and (ii) the consistency of the way LVH regression and blood pressure (BP) control were reported.

METHODS

Studies identified by a PubMed search were eligible for inclusion in the analysis, if they fulfilled the following criteria: (i) publication in a peer-reviewed journal within the last 12 years; (ii) double blind, randomized, controlled, parallel-group design; (iii) numerosity of at least 50 adult hypertensive subjects; (iv) follow-up duration of at least 6 months; (v) comparison between single-drugs or association regimens; (vi) LV mass (LVM) or wall thickness measured by echocardiography.

RESULTS

Thirty-nine trials, including 9,162 hypertensive subjects of both genders in 78 active treatment arms or in 6 placebo arms were identified. Definition of LVH was provided by 34 studies (87.1%) according to 19 different criteria. All trials evaluated LVH regression as the absolute or relative changes of continuous variables such as LVM index (LVMI) or LV wall thickness. Data concerning prevalence rates of LVM normalization were reported in 12 studies (30.7%). The percentage of patients reaching BP target (<140/90 mm Hg) was reported in 11 studies (28.2%).

CONCLUSIONS

Our findings indicate that (i) definition of hypertensive LVH phenotype is extremely variable, and (ii) no precise information on LVH regression rates or changes in LV geometrical patterns, as well as on target BP, is provided by the majority of papers.

Left ventricular (LV) geometry and dipping state are determinants of LV mass reduction with angiotensin-converting enzyme inhibitor antihypertensive treatment

OBJECTIVES

Left ventricular hypertrophy is a major risk predictor in hypertensive patients and its regression is beneficial in terms of prognosis. The aim of this observational, open-labeled study was to investigate the effect of left ventricular geometry and dipping pattern on left ventricular mass reduction after chronic treatment with angiotensin-converting enzyme inhibitors, in a large population of hypertensive patients.

METHODS

We evaluated untreated patients with mild to moderate essential hypertension, before and 6 months after treatment with angiotensin-converting enzyme inhibitor monotherapy or angiotensin-converting enzyme inhibitor-low-dose thiazide combination. Left ventricular mass index, relative wall thickness and geometry pattern were derived from echocardiography. Dipping state was determined with 24-h ambulatory blood pressure monitoring at enrollment.

RESULTS

Overall, left ventricular mass index decrease in the 1400 patients (mean age 52.5 years) who completed the study was 12.9% of baseline value (P<0.00001). After adjusting for pretreatment value, left ventricular mass index reduction was similar with all angiotensin-converting enzyme inhibitors used [P= NS (not significant)], but it was higher in nondippers than dippers (14.1 vs. 12.3%, P<0.0001) and in patients with than without baseline left ventricular hypertrophy (14.6 vs. 11.3%, P<0.0001). We observed a stepwise augmentation of left ventricular mass index decrease with worsening left ventricular geometry (P<0.001). In multivariable analysis, impaired left ventricular geometry and blunted nocturnal blood pressure fall before treatment were independent predictors of a high left ventricular mass index reduction after treatment, independent of blood pressure fall, pretreatment left ventricular mass index, and other potential confounders.

CONCLUSION

In essential hypertension, left ventricular geometry and dipping state are independent determinants of left ventricular mass reduction with angiotensin-converting enzyme inhibitor treatment. All angiotensin-converting enzyme inhibitors are efficient in decreasing left ventricular mass.

Evaluation of the Electrocardiographic Criteria for Left Ventricular Hypertrophy With Use of Three-Dimensional Echocardiography

BACKGROUND

Left ventricular hypertrophy (LVH) is a common condition that carries an increased risk of cardiovascular events. Use of ECG in detection of LVH is limited because of the reported low sensitivity. Conventional echocardiographic techniques used as the standard for estimating left ventricular (LV) mass have limitations related to the position of the image plane and shape of the ventricle. Three-dimensional echocardiography is free of these limitations and therefore is more accurate. We hypothesized that accuracy of ECG criteria for LVH would improve when LV mass was assessed by three-dimensional echocardiography.

RESULTS

For most of the criteria, sensitivity, specificity and accuracy improved when LV mass was assessed by three-dimensional echocardiography. Two-dimensional echocardiography significantly overestimated LV mass as compared with the three-dimensional method.

CONCLUSIONS

Sensitivity, specificity, and accuracy of the ECG criteria improved when LV mass was estimated by three-dimensional echocardiography. This improvement may be attributed at least in part to superior accuracy of three-dimensional measurements.

A meta-analysis of the effects of treatment on left ventricular mass in essential hypertension

PURPOSE

Antihypertensive medications have different effects on left ventricular mass. We conducted a meta-analysis of double-blind trials that measured the effects of antihypertensive therapy on left ventricular mass.

METHODS

Medical databases and review articles were screened for double-blind, randomized controlled trials (through September 2002) that reported the effects of diuretics, beta-blockers, calcium antagonists, angiotensin-converting enzyme (ACE) inhibitors, or angiotensin II receptor antagonists on echocardiographic left ventricular mass in essential hypertension. Treatment arms of the same drug class, weighted for the number of patients, were combined. Analysis of covariance was performed to detect differences among drug classes in effects on left ventricular structure.

RESULTS

Eighty trials with 146 active treatment arms (n = 3767 patients) and 17 placebo arms (n = 346 patients) were identified. Adjusted for treatment duration and change in diastolic blood pressure, there was a significant difference (P = 0.004) among medication classes: left ventricular mass index decreased by 13% with angiotensin II receptor antagonists (95% confidence interval [CI]: 8% to 18%), by 11% with calcium antagonists (95% CI: 9% to 13%), by 10% with ACE inhibitors (95% CI: 8% to 12%), by 8% with diuretics (95% CI: 5% to 10%), and by 6% with beta-blockers (95% CI: 3% to 8%). In pairwise comparisons, angiotensin II receptor antagonists, calcium antagonists, and ACE inhibitors were more effective at reducing left ventricular mass than were beta-blockers (all P <0.05 with Bonferroni correction).

CONCLUSIONS

Antihypertensive drug classes have different effects on left ventricular mass reduction. Whether a greater reduction of left ventricular mass results in better clinical outcomes remains to be determined.

Candesartan cilexetil plus hydrochlorothiazide combination: a review of its use in hypertension

The combination of candesartan cilexetil [an angiotensin II type 1 (AT(1)) receptor antagonist] plus hydrochlorothiazide (a thiazide diuretic), has been used in the treatment of patients with hypertension. The blood pressure (BP) lowering effect of various doses of this combination, administered orally once a day for 4 to 52 weeks, has been demonstrated in clinical trials. These studies showed that combinations of candesartan cilexetil 4 to 16 mg with hydrochlorothiazide 12.5 or 25 mg induced significant reductions reductions in systolic (S) BP and diastolic (D) BP from baseline in patients with mild to severe hypertension. Data from clinical trials indicated that reductions in BP induced by candesartan cilexetil 4 to 32 mg/hydrochlorothiazide 12.5 mg combinations were significantly greater than those observed after monotherapy with either drug. Treatment for 8 weeks with candesartan cilexetil 16 mg/hydrochlorothiazide 12.5 mg or candesartan cilexetil 16 mg induced SBP/DBP reductions of 12.0/7.5 mm Hg and 7.5/5.5mm Hg, respectively (p < 0.05 both comparisons). Moreover, data from a randomised, double-blind, placebo-controlled, dose-finding study in 1038 patients with mild to moderate hypertension showed that the greatest reductions in SBP/DBP were achieved by candesartan cilexetil 16 mg/hydrochlorothiazide 12.5 mg. Significant differences in BP reduction in favour of the combination were observed when hypertensive patients were given candesartan cilexetil 4 or 8 mg/hydrochlorothiazide 12.5 mg or hydrochlorothiazide monotherapy for 8 weeks. Additionally, greater efficacy of the combination compared to monotherapy with either drug was demonstrated by response rates to treatment. Moreover, a fixed combination of candesartan cilexetil 16 mg/hydrochlorothiazide 12.5 mg demonstrated a greater antihypertensive effect than losartan 50 mg/hydrochlorothiazide 12.5 mg in two clinical trials. Candesartan cilexetil 8 mg/hydrochlorothiazide 12.5 mg showed a similar antihypertensive effect compared with that of combined lisinopril 10 mg/hydrochlorothiazide 12.5 mg. Candesartan cilexetil/hydrochlorothiazide combination was well tolerated in patients with hypertension. Combined data from placebo-controlled trials showed that most adverse events were uncommon and not serious. Patients receiving combination therapy exhibited, among other adverse events, headache (3.2 vs 5.5% for candesartan cilexetil/hydrochlorothiazide and placebo, respectively), back pain (3.0 vs 2.4%), dizziness (2.6 vs 1.2%) and respiratory infection (2.5 vs 1.4%). Moreover, 3.3 and 2.7% of patients receiving candesartan cilexetil/hydrochlorothiazide or placebo, respectively, discontinued treatment because of adverse events.

CONCLUSION

The combination of candesartan cilexetil and hydrochlorothiazide (AT(1)-receptor antagonist and thiazide diuretic, respectively) is an effective treatment for patients with hypertension. Data from randomised, double-blind, placebo-controlled clinical trials showed that this combination is significantly more efficacious than either agent alone. Moreover, the combination of these two agents showed an excellent adverse event profile. Current data support the use of this combination as an alternative when monotherapy with either agent is not effective, and there are no compelling or specific indications for other drugs. However, data from large clinical trials, evaluating morbidity and mortality outcomes, are needed to determine the precise role of candesartan cilexetil/hydrochlorothiazide combination in the treatment of patients with hypertension.

Analysis of T-wave morphology from the 12-lead electrocardiogram for prediction of long-term prognosis in male US veterans

BACKGROUND

The aim of the present study was to assess the prognostic value of novel repolarization descriptors from the 12-lead ECG in a large cohort of US veterans.

METHODS AND RESULTS

Male US veterans (n=813) with cardiovascular disease had digital 12-lead ECGs recorded at the VA Medical Center, Washington, DC, between 1984 and 1991. The patient series was retrospectively compiled in 1991; follow-up was prospectively assessed until 2000. Novel ECG variables characterizing repolarization and the T-wave loop were automatically analyzed. Of 772 patients with technically analyzable data, 252 patients (32.6%) died after a mean follow-up of 10.4 +/- 3.8 years. Direct comparison between dead and alive patients showed that the so-called T-wave residua (the absolute and relative amount of nondipolar contents within the T wave) predicted mortality (111 900 +/- 164 700 versus 85 600 +/- 144 800 between dead and alive patients, P<0.0002; and 0.43 +/- 0.62% versus 0.33 +/- 0.56%, P<0.0005 for the absolute and relative T-wave residuum, respectively). On Cox regression analysis entering age, left ventricular ejection fraction, echocardiographic left ventricular hypertrophy, and either of the T-wave residua, risk prediction was independent for the absolute (P=0.022) and for the relative (P=0.006) T-wave residuum, respectively, with age (P<0.0001), presence of left ventricular hypertrophy (P=0.002), and left ventricular ejection fraction (P=0.004) also being predictors of survival.

CONCLUSIONS

The heterogeneity of myocardial repolarization, measured by the so-called T-wave residuum in the ECG, confers long-term independent prognostic information in US veterans with cardiovascular disease.

Regression of left ventricular hypertrophy in hypertensive patients treated with indapamide SR 1.5 mg versus enalapril 20 mg: the LIVE study

OBJECTIVE

To compare the efficacy of indapamide sustained release (SR) 1.5 mg and enalapril 20 mg at reducing left ventricular mass index (LVMI) in hypertensive patients with left ventricular hypertrophy (LVH).

DESIGN

The LIVE study (left ventricular hypertrophy regression, indapamide versus enalapril) was a 1 year, prospective, randomized, double-blind study. For the first time, a committee validated LVH before inclusion, provided on-going quality control during the study, and performed an end-study reading of all echocardiograms blinded to sequence.

SETTING

European hospitals, general practitioners and cardiologists.

PATIENTS

Hypertensive patients aged > or = 20 years with LVH (LVMI in men > 120 g/m2; LVMI in women > 100 g/m2). Data were obtained from 411 of 505 randomized patients.

INTERVENTIONS

Indapamide SR 1.5 mg, or enalapril 20 mg, daily for 48 weeks.

MAIN OUTCOME MEASURES

LVMI variation in the perprotocol population.

RESULTS

Indapamide SR 1.5 mg significantly reduced LVMI (-8.4 +/- 30.5 g/m2 from baseline; P< 0.001), but enalapril 20 mg did not (-1.9 +/- 28.3 g/m2). Indapamide SR 1.5 mg reduced LVMI significantly more than enalapril 20 mg: -6.5 g/m2, P = 0.013 (-4.3 g/m2 when adjusted for baseline values; P = 0.049). Both drugs equally and significantly reduced blood pressures (P< 0.001), without correlation with LVMI changes. Indapamide SR progressively reduced wall thicknesses throughout the 1-year treatment period. In contrast, the effect of enalapril observed at 6 months was not maintained at 12 months.

CONCLUSIONS

Indapamide SR 1.5 mg was significantly more effective than enalapril 20 mg at reducing LVMI in hypertensive patients with LVH.

Current status of safety and efficacy of calcium channel blockers in cardiovascular diseases: a critical analysis based on 100 studies

Recently, serious concerns have been expressed about the long-term safety of the calcium channel blockers (CCBs) as a group. Safety and efficacy are, however, ultimately linked to each other; therefore both must be evaluated especially in the therapy of angina and hypertension, the main clinical indications for CCBs. The structural, functional, and pharmacokinetic heterogeneity of CCBs means that the efficacy and dangers of one subclass, such as the short-acting dihydropyridines (DHPs), in one situation, such as unstable angina, do not necessarily apply in other clinical situations. One hundred studies are reviewed according to their methods of data collection: case series, case control, cohort, randomized controlled trials (RCTs), and meta-analyses. Large, well-designed RCTs and the meta-analyses based on these trials remain the gold standard. Observational studies, though potentially less reliable sources of information because of selection bias, may nevertheless produce hypotheses that must then be tested in RCTs. Regarding safety, both observational studies and RCTs suggest that adverse effects of CCBs may be linked to short-acting agents, specifically short-acting nifedipine. Two good studies favor the safety of verapamil, even in short-acting form. Incomplete but increasing overall evidence favors the safety of longer-acting DHPs. Heart failure remains a class contraindication to the use of all CCBs, with some exceptions. Regarding efficacy, there are positive results of RCTs with CCBs in 2 specific clinical situations, namely, verapamil in postinfarct protection in the absence of pre-existing heart failure, and 2 outcome studies on hypertension with longer acting DHPs. These results cannot automatically be applied to other clinical situations and to other CCBs. For example, there is no evidence for the safety or efficacy of DHPs used without beta blockers in postinfarct patients. In diabetic hypertensives, 2 relatively large RCTs show that the blood pressure can be reduced by DHP-based therapy in diabetics, with a reduction in hard end points. To achieve current blood pressure goals, combination therapy is almost always necessary, and in diabetics there is strong evidence that 1 essential component should be an angiotensin converting enzyme inhibitor. The future aim with CCBs must be to obtain a large database gathered from RCTs, which will give the same certainty about efficacy and safety that already holds for use of the diuretics in hypertension, beta-blockers in postmyocardial infarction patients, and the angiotensin converting enzyme inhibitors in heart failure.

Optimal antihypertensive therapy for prevention and treatment of left ventricular hypertrophy

Left ventricular hypertrophy (LVH) is considered an adaptation to a pressure load on the left ventricle and is common in hypertensive patients. The condition is a profound risk factor for cardiovascular events, greater than and independent of blood pressure. It is now recognized in hypertension management guidelines as an indication for more stringent blood pressure control. All of the first-line antihypertensive agents have been shown to variably regress LVH, but no definitive evidence yet shows that one agent is superior to others in decreasing risk independent of blood pressure control. Although some evidence suggests that reduction of LVH is associated with improved prognosis independent of blood pressure control, relative efficacy of drug classes in this regard has yet to be demonstrated. At present, recommendations for optimal therapy in hypertensive patients with LVH must rest on the presence of underlying cardiac and noncardiac conditions, with the understanding that the major classes of antihypertensive agents will probably decrease LVH.

Predictors of congestive heart failure in the elderly: the Cardiovascular Health Study

OBJECTIVES

We sought to characterize the predictors of incident congestive heart failure (CHF), as determined by central adjudication, in a community-based elderly population.

BACKGROUND

The elderly constitute a growing proportion of patients admitted to the hospital with CHF, and CHF is a leading source of morbidity and mortality in this group. Elderly patients differ from younger individuals diagnosed with CHF in terms of biologic characteristics.

METHODS

We analyzed data from the Cardiovascular Health Study, a prospective population-based study of 5,888 elderly people >65 years old (average 73 +/- 5, range 65 to 100) at four locations. Multiple laboratory measures of cardiovascular structure and function, blood chemistries and functional assessments were obtained.

RESULTS

During an average follow-up of 5.5 years (median 6.3), 597 participants developed incident CHF (rate 19.3/1,000 person-years). The incidence of CHF increased progressively across age groups and was greater in men than in women. On multivariate analysis, other independent predictors included prevalent coronary heart disease, stroke or transient ischemic attack at baseline, diabetes, systolic blood pressure (BP), forced expiratory volume 1 s, creatinine >1.4 mg/dl, C-reactive protein, ankle-arm index <0.9, atrial fibrillation, electrocardiographic (ECG) left ventricular (LV) mass, ECG ST-T segment abnormality, internal carotid artery wall thickness and decreased LV systolic function. Population-attributable risk, determined from predictors of risk and prevalence, was relatively high for prevalent coronary heart disease (13.1%), systolic BP > or =140 mm Hg (12.8%) and a high level of C-reactive protein (9.7%), but was low for subnormal LV function (4.1%) and atrial fibrillation (2.2%).

CONCLUSIONS

The incidence of CHF is high in the elderly and is related mainly to age, gender, clinical and subclinical coronary heart disease, systolic BP and inflammation. Despite the high relative risk of subnormal systolic LV function and atrial fibrillation, the actual population risk of these for CHF is small because of their relatively low prevalence in community-dwelling elderly people.

Left Ventricular Hypertrophy

The presence of left ventricular hypertrophy (LVH) as a treatable entity is of particular importance in patients with primary hypertension. Because LVH is associated with a strong risk of adverse clinical events (eg, heart failure, ischemic events, and cardiovascular death) and because evidence from retrospective studies suggests that regression of LVH, along with a decrease in blood pressure, may help modify these outcomes, the use of antihypertensive agents that have been shown to promote regression of LVH has been recommended. These include diuretics, beta-blockers (except those with intrinsic sympathomimetic activity ), angiotensin-converting enzyme (ACE) inhibitors, calcium channel blockers, peripheral alpha(1)-blockers, and central alpha(2)-stimulators. Agents to be avoided include direct arterial vasodilators (eg, hydralazine and minoxidil), which have strong sympathetic stimulating properties and tend to maintain LVH despite lowering blood pressure. The use of ACE inhibitors is increasing. Unfortunately, the cost of these agents is higher than that of some other classes of agents, such as diuretics, which show excellent evidence of regression of hypertrophy. African-American and elderly persons, in particular, may benefit from diuretics for treatment of hypertension as well as reduction of left ventricular (LV) mass. Beta-blockers should be considered in the elderly, especially those with greatly thickened LV walls and small chamber sizes, factors associated with hyperdynamic systolic performance, systolic midcavity obliteration, and diastolic relaxation abnormalities on echocardiography. Calcium channel blockers may also be useful in patients with LVH who have normal systolic performance and diastolic compliance abnormalities. The purpose of serial echocardiographic studies in patients already being treated for hypertension is to ensure that LV geometry has not worsened and that function is unchanged or improved (especially with respect to previously noted diastolic Doppler inflow abnormalities). Considerable changes in estimated LV mass (>60 g on serial intrapatient evaluation) are needed before the clinician can conclude with confidence that LV mass has decreased. More specific definitive recommendations based on the outcomes of current large-scale clinical trials are awaited.