A comparison of intervention with losartan or captopril in acute myocardial infarction

Angiotensin-converting enzyme inhibitor induced cough compared with placebo, and other antihypertensives: A systematic review, and network meta-analysis

Studies have shown that angiotensin converting enzyme inhibitors (ACEIs) are superior in primary and secondary prevention for cardiac mortality and morbidity to angiotensin receptor blocker (ARBs). One of the common side effects from ACEI is dry cough. The aims of this systematic review, and network meta-analysis are to rank the risk of cough induced by different ACEIs and between ACEI and placebo, ARB or calcium channel blockers (CCB). We performed a systematic review, and network meta-analysis of randomized controlled trials to rank the risk of cough induced by each ACEI and between ACEI and placebo, ARB or CCB. A total of 135 RCTs with 45,420 patients treated with eleven ACEIs were included in the analyses. The pooled estimated relative risk (RR) between ACEI and placebo was 2.21 (95% CI: 2.05-2.39). ACEI had more incidences of cough than ARB (RR 3.2; 95% CI: 2.91, 3.51), and pooled estimated of RR between ACEI and CCB was 5.30 (95% CI: 4.32-6.50) Moexipril ranked as number one for inducing cough (SUCRA 80.4%) and spirapril ranked the least (SUCRA 12.3%). The order for the rest of the ACEIs are as follows: ramipril (SUCRA 76.4%), fosinopril (SUCRA 72.5%), lisinopril (SUCRA 64.7%), benazepril (SUCRA 58.6%), quinapril (SUCRA 56.5%), perindopril (SUCRA 54.1%), enalapril (SUCRA 49.7%), trandolapril (SUCRA 44.6%) and, captopril (SUCRA 13.7%). All ACEI has the similar risk of developing a cough. ACEI should be avoided in patients who have risk of developing cough, and an ARB or CCB is an alternative based on the patient's comorbidity.

Effect of captopril on post-infarction remodelling visualized by light sheet microscopy and echocardiography

Angiotensin converting enzyme inhibitors, among them captopril, improve survival following myocardial infarction (MI). The mechanisms of captopril action remain inadequately understood due to its diverse effects on multiple signalling pathways at different time periods following MI. Here we aimed to establish the role of captopril in late-stage post-MI remodelling. Left anterior descending artery (LAD) ligation or sham surgery was carried out in male C57BL/6J mice. Seven days post-surgery LAD ligated mice were allocated to daily vehicle or captopril treatment continued over four weeks. To provide comprehensive characterization of the changes in mouse heart following MI a 3D light sheet imaging method was established together with automated image analysis workflow. The combination of echocardiography and light sheet imaging enabled to assess cardiac function and the underlying morphological changes. We show that delayed captopril treatment does not affect infarct size but prevents left ventricle dilation and hypertrophy, resulting in improved ejection fraction. Quantification of lectin perfused blood vessels showed improved vascular density in the infarct border zone in captopril treated mice in comparison to vehicle dosed control mice. These results validate the applicability of combined echocardiographic and light sheet assessment of drug mode of action in preclinical cardiovascular research.

Cardiovascular outcomes in high-risk patients without heart failure treated with ARBs: a systematic review and meta-analysis

BACKGROUND AND OBJECTIVE

Angiotensin II type 1 receptor antagonists (ARBs) are widely used as a substitute for angiotensin-converting enzyme inhibitors (ACEIs) to treat patients without heart failure, but their effect on cardiovascular morbidity and mortality has not been clearly determined. A systematic review and meta-analysis was undertaken to determine the impact of ARBs on cardiovascular outcomes in high-risk patients without heart failure.

METHODS

A computerized literature search was carried out using PubMed, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, and EMBASE, from January 1990 to April 2008. The following search terms were used: 'hypertension', 'clinical trial', 'sartan', 'ARB', 'angiotensin receptor antagonist', 'losartan', 'candesartan', 'valsartan', 'irbesartan', 'eprosartan', 'telmisartan', 'olmesartan', 'coronary disease', 'coronary heart disease', 'myocardial infarction', 'cardiovascular disease', 'cerebrovascular disease', and 'stroke'. Criteria for inclusion of clinical trials in our meta-analysis were the use of a randomized control group not receiving an ARB and the availability of outcome data for any one of four endpoints: myocardial infarction (MI), stroke, cardiovascular death, and all-cause death (these were not always pre-specified endpoints in all trials). Out of 45 potentially relevant studies, 37 trials met the inclusion criteria. We tabulated all occurrences of these four adverse outcomes.

RESULTS

Homogenous subgroups were combined by means of a fixed-effects model, while heterogenous subgroups were not combined. In the subgroup without heart failure, ARBs, when compared with the control group, had an odds ratio of 1.09 (95% CI 1.00, 1.18; p = 0.05) for MI. Other endpoints, namely, cardiovascular death and all-cause death, did not reach statistical significance. There was a clear trend for fewer strokes in the ARB group, but these studies were clearly heterogenous, and therefore a pooled risk estimate was not computed.

CONCLUSION

After pooling more than 89 000 patients, there is no evidence to suggest that ARBs confer cardiovascular protection akin to ACEIs, and the results that emerged are not in favor of ARB therapy in terms of its use as a substitute for ACEIs in non-heart failure patients. ARBs may have a small benefit in terms of stroke risk, but the studies are heterogenous, making it very difficult to quantify this effect. Given that ACEIs protect against both stroke and MI, caution is advised in the use of ARBs as a substitute for ACEIs in patients without a heart failure indication, who are tolerant of an ACEI.

Angiotensin receptor blockers and risk of myocardial infarction: systematic review

OBJECTIVE

To evaluate the effect of angiotensin receptor blockers on the risk of myocardial infarction in patients at risk for cardiovascular events.

DESIGN

Systematic review of controlled trials of angiotensin receptor blockers.

DATA SOURCES

Medline, Embase, Cochrane central register of controlled trials, hand search, and contact with investigators.

SELECTION OF STUDIES

Predefined criteria were used to select controlled clinical trials comparing use of angiotensin receptor blockers with angiotensin converting enzyme (ACE) inhibitors or placebo in patients at risk for cardiovascular events. Data were extracted for patients' characteristics, interventions, quality of trials, and rates of myocardial infarction.

RESULTS

19 studies with 31,569 patients were included in the analysis. Two studies investigated the use of angiotensin receptor blockers in hypertensive patients, four studies in patients with diabetes and nephropathy, 10 studies in patients with heart failure, and three in patients with recent myocardial infarction or ischaemic syndrome. 11 studies of 21,062 patients allowed for comparison between angiotensin receptor blockers and placebo; nine studies of 10,625 patients allowed for comparison between angiotensin receptor blockers and ACE inhibitors. Use of angiotensin receptor blockers was not associated with increased risk of myocardial infarction compared with placebo (odds ratio 0.94, 95% confidence interval 0.75 to 1.16) nor with increased risk of myocardial infarction compared with ACE inhibitors (1.01, 0.87 to 1.16).

CONCLUSIONS

Treatment with angiotensin receptor blockers was not associated with a significantly increased risk of myocardial infarction. The 95% confidence intervals do, however, not exclude an increase of up to 16% in the risk of myocardial infarction or a reduction in risk of up to 25%. Until further information specifically dealing with this issue is available from large prospective trials, our findings may alleviate recent concerns over the safety of this class of medications.

First dose hypotension after angiotensin converting enzyme inhibitor captopril and angiotensin II blocker losartan in patients with acute myocardial infarction

BACKGROUND

First dose hypotension after the administration of an angiotensin-converting enzyme inhibitor in patients with acute myocardial infarction is one of the most important adverse events of this type of treatment. There is no information about first dose hypotension after angiotensin type 1-receptor blocker in this type of patient.

AIM

To compare the first dose responses to low dose captopril and losartan in patients with acute myocardial infarction.

METHODS

Single blind, randomised, multicentric, prospective study. Patients (n=320) with confirmed acute myocardial infarction, age >18 years, treated by direct percutaneous transluminal coronary angioplasty, thrombolysis and/or heparin, were randomised to receive a single dose of 6.25-12.5 mg captopril or 12.5-25 mg losartan within 24 h of hospital admission. Baseline laboratory and clinical examinations were performed before entering the study. Blood pressure monitoring started at hospital admission and continued for at least 8 h after the medication (second dose of captopril was given after 8 h).

RESULTS

The maximal blood pressure fall appeared about 1 h after the first dose of captopril and 3.5 h after the first dose of losartan. Patients in the captopril group had significantly higher incidence of asymptomatic hypotension (38%) than patients treated with losartan (24%) (P<0.001). No difference in hypotension requiring a change in medication was observed.

CONCLUSION

Low dose of losartan is safe for initiating therapy in patients with acute myocardial infarction within 24 h of hospital admission.