Effects of spironolactone on cardiac sympathetic nerve activity and left ventricular remodelling after reperfusion therapy in patients with first ST-segment elevation myocardial infarction

Effects of mineralocorticoid receptor antagonist eplerenone on cardiac sympathetic nerve activity and left ventricular remodeling after reperfusion therapy in patients with first ST-segment elevation myocardial infarction

PURPOSE

The activation of the renin-angiotensin-aldosterone system prevents the uptake of norepinephrine and promotes structural remodeling of the heart. The mineralocorticoid receptor antagonist (MRA) eplerenone prevents left ventricular (LV) remodeling in patients with acute myocardial infarction, but its influence on cardiac sympathetic nerve activity (CSNA) has not been determined.

METHODS

We retrospectively evaluated the first ST-segment elevation myocardial infarction (STEMI) patients in our database who underwent 123I-metaiodobenzylguanidine (MIBG) scintigraphy 3 weeks after admission. Eighty-four STEMI patients after primary coronary angioplasty were selected, and used propensity score matching to compare patients who treated with MRA (N = 42), and those who did not (N = 42). The LV end-diastolic volume, end-systolic volume, and ejection fraction were determined by echocardiography, and plasma procollagen type III amino terminal peptide (PIIINP) was measured before and 3 weeks after treatment. The delayed total defect score (TDS), delayed heart/mediastinum count (H/M) ratio, and washout rate (WR) were determined using 123I-MIBG scintigraphy after 3 weeks.

RESULTS

Following primary angioplasty, age, gender, risk factors, culprit coronary artery, peak serum creatine phosphokinase concentration, and recanalization time were similar in the two groups. However, the MRA group showed significantly lower TDS and WR values (TDS: 22.8 ± 8.1 vs 32.2 ± 11.5, P < 0.005; WR: 31.1 ± 9.0% vs 42.7 ± 9.9%, P < 0.001) and a significantly higher H/M ratio (2.23 ± 0.41 vs 2.03 ± 0.36, P < 0.05) than the non-MRA group. The degree of change in LV parameters, and PIIINP were more favorable in the MRA group than in the non-MRA group. Moreover, multiple linear regression analyses revealed that both WR and not MRA treatment were significant predictor for LV remodeling, along with PIIINP concentrations.

CONCLUSION

Administration of eplerenone improves CSNA and prevents LV remodeling in patients with a first STEMI.

Non-steroidal mineralocorticoid receptor antagonists in cardiorenal disease

Despite existing treatments, patients with heart failure and chronic kidney disease (CKD) remain at high risk for adverse outcomes and progression to end-stage disease. Steroidal mineralocorticoid receptor antagonists (MRAs) such as spironolactone and eplerenone reduce mortality but remain under-prescribed due to the perceived risk of hyperkalaemia and hormonal side effects. The discovery of non-steroidal MRAs represents a major new dimension in cardiorenal disease therapy. Non-steroidal MRAs have high affinity and specificity for the mineralocorticoid receptor (MR) and differ from both steroidal agents and each other with respect to important physiochemical, pharmacodynamic, and pharmacokinetic parameters. Similar to their steroidal counterparts, they have beneficial anti-inflammatory, anti-remodelling, and anti-fibrotic properties in the kidneys, heart, and vasculature. There are several non-steroidal MRAs under development and clinical assessment; of these, only esaxerenone and finerenone are approved for treatment globally. In Japan, esaxerenone is approved for essential hypertension and has been studied in diabetic nephropathy. Compared with steroidal MRAs, finerenone more potently inhibits MR co-regulator recruitment and fibrosis and distributes more evenly between the heart and kidneys. The landmark Phase III trials FIGARO-DKD and FIDELIO-DKD demonstrated that finerenone-reduced major kidney and cardiovascular events on top of maximally tolerated renin-angiotensin-aldosterone system inhibition in patients with CKD associated with Type 2 diabetes. Non-steroidal MRAs are currently under evaluation in heart failure and for synergistic treatment with sodium-glucose contransporter 2 inhibitors. These ground-breaking agents could become an important therapy across the spectrum of cardiorenal disease.

Identification of Mineralocorticoid Receptors, Aldosterone, and Its Processing Enzyme CYP11B2 on Parasympathetic and Sympathetic Neurons in Rat Intracardiac Ganglia

Recent interest has focused on the mineralocorticoid receptor (MR) and its impact on the myocardium and the performance of the heart. However, there is a lack of evidence about MR expression and its endogenous ligand aldosterone synthesis with specific regard to the intrinsic cardiac nervous system. Therefore, we looked for evidence of MR and aldosterone in sympathetic and parasympathetic neurons of intracardiac ganglia. Tissue samples from rat heart atria were subjected to conventional reverse-transcriptase polymerase chain reaction (PCR), Western blot, and double immunofluorescence confocal analysis of MR, corticosterone-inactivating enzyme 11β-hydroxysteroid-dehydrogenase-2 (11β-HSD2), aldosterone, and its processing enzyme CYP11B2 together with the neuronal markers vesicular acetylcholine transporter (VAChT) and tyrosine hydroxylase (TH). Our results demonstrated MR, 11β-HSD2, and CYP11B2 specific mRNA and protein bands in rat heart atria. Double immunofluorescence labeling revealed coexpression of MR immunoreactivity with VAChT in large diameter parasympathetic principal neurons. In addition, MR immunoreactivity was identified in TH-immunoreactive small intensely fluorescent (SIF) cells and in nearby VAChT- and TH-immunoreactive nerve terminals. Interestingly, the aldosterone and its synthesizing enzyme CYP11B2 and 11β-HSD2 colocalized in MR– immunoreactive neurons of intracardiac ganglia. Overall, this study provides first evidence for the existence of not only local expression of MR, but also of 11β-HSD2 and aldosterone with its processing enzyme CYP11B2 in the neurons of the cardiac autonomic nervous system, suggesting a possible modulatory role of the mineralocorticoid system on the endogenous neuronal activity on heart performance.

Assessment of therapeutic effects of statin on cardiac sympathetic nerve activity after reperfusion therapy in patients with first ST-segment elevation myocardial infarction and normal low-density lipoprotein cholesterol

BACKGROUND

Statin treatment reduces enhanced cardiac sympathetic nerve activity (CSNA) in patients with heart disease, and reduces adverse cardiac events in patients with coronary artery disease.

METHODS

We retrospectively evaluated the first ST-segment elevation myocardial infarction (STEMI) patients and low-density lipoprotein cholesterol < 120 mg/dL in our database who underwent 123I-metaiodobenzylguanidine (MIBG) scintigraphy 3 weeks after admission. Sixty STEMI patients after primary coronary angioplasty were selected, and used propensity score matching to compare patients treated with strong statin (n = 30), and those who did not (n = 30). Moreover, echocardiographic left ventricular (LV) parameters were determined, and plasma procollagen type III amino terminal peptide (PIIINP) was also measured before and 3 weeks after treatment.

RESULTS

Following primary angioplasty, age, gender, risk factors, culprit coronary artery, peak serum creatine phosphokinase concentration, and recanalization time were similar in the two groups. However, the statin group showed significantly lower delayed total defect score and washout rate evaluated by 123I-MIBG scintigraphy (22.4 ± 8.1 vs. 29.6 ± 10.5; P < 0.01, and 30.4 ± 8.9% vs. 40.1 ± 11.4%; P < 0.005, respectively) and higher delayed heart/mediastinum count ratio (2.17 ± 0.38 vs. 1.96 ± 0.30, P < 0.05) compared with the non-statin group. Moreover, the degree of change in LV parameters and PIIINP was more favorable in the statin group than in the non-statin group.

CONCLUSIONS

Administration of statin improves CSNA after reperfusion therapy in patients with first STEMI.

Spironolactone Improves the All-Cause Mortality and Re-Hospitalization Rates in Acute Myocardial Infarction with Chronic Kidney Disease Patients

Background: Mineralocorticoid receptor antagonists (MRA) improve outcomes in chronic kidney disease (CKD) and acute myocardial infarction (AMI) patients. However, the lack of evidence regarding long-term clinical outcomes in the use of MRA, including spironolactone, in patients with AMI combined with CKD.

Objectives: This study aimed to investigate whether spironolactone could significantly reduce the risk of all-cause mortality and re-admission in patients with AMI and CKD.

Methods: In this single center, observational, retrospective, registry based clinical study, a total of 2,465 AMI patients were initially screened; after excluding patients with estimated glomerular filtration rate more than 60 ml/min/1.73 m², 360 patients in the standard treatment group and 200 patients in the spironolactone group met the criteria. All enrolled patients follow-up for 30 months. The primary outcomes were all-cause mortality and re-admission. The key safety outcome was hyperkalemia rates during the 30 months follow-up period.

Results: 160 (44.4%) and 41 (20.5%) patients in the standard treatment and spironolactone groups died, respectively [hazard ratio (HR): 0.389; 95% confidence interval (CI): 0.276–0.548; p < 0.001]. Re-admission occurred in 217 (60.3%) and 95 (47.5%) patients in the standard treatment and spironolactone groups, respectively (HR: 0.664; 95% CI: 0.522–0.846; p = 0.004). The spironolactone group was divided into two based on the daily dose, low dose group (no more than 40 mg) and high dose group (more than 40 mg); the differences in the mortality rate between low dose group (16.7%) and the standard treatment group (44.4%) (HR: 0.309; 95% CI: 0.228–0.418; p < 0.001) and high dose group (34.1%) (HR: 0.429; 95% CI: 0.199–0.925; p = 0.007) were significant. The differences in re-hospitalization rate between low dose group (43.6%) and the standard treatment group (60.3%) (HR: 0.583; 95% CI: 0.457–0.744; p < 0.001) and high dose group (61.4%) (HR: 0.551; 95% CI: 0.326–0.930; p = 0.007) was significant. Hyperkalemia occurred in 18 (9.0%) and 18 (5.0%) patients in the spironolactone group and standard treatment group, respectively (HR: 1.879; 95% CI: 0.954–3.700; p = 0.068). Whereas, Hyperkalemia occurred in high dose group (20.5%) significantly more often than in the standard treatment group (p < 0.001) and low dose group (5.8%) (p = 0.003).

Conclusion: Using MRA, such as spironolactone, may substantially reduce the risk of both all-cause mortality and re-admission in patients with AMI and CKD; the use of low-dose spironolactone has the best efficacy and safety. However, this was a relatively small sample size, single center, observational, retrospective, registry based clinical study and further prospective evaluation in adequately powered randomized trials were needed before further use of spironolactone in AMI with CKD population.

The role of aldosterone inhibitors in cardiac ischemia-reperfusion injury

Myocardial ischaemia-reperfusion (I/R) injury is a well-known term for exacerbation of cellular destruction and dysfunction after the restoration of blood flow to a previously ischaemic heart. A vast number of studies that have demonstrated that the role of mineralocorticoids in cardiovascular diseases is based on the use of pharmacological mineralocorticoid receptor (MR) antagonists. This review paper aimed to summarize current knowledge on the effects of MR antagonists on myocardial I/R injury as well as postinfarction remodeling. Animal models, predominantly the Langendorff technique and left anterior descending coronary artery occlusion, have confirmed the potency of MR antagonists as preconditioning and postconditioning agents in limiting infarct size and postinfarction remodeling. Several preclinical studies in rodents have established and proved possible mechanisms of cardioprotection by MR antagonists, such as reduction of oxidative stress, reduction of inflammation, and apoptosis, therefore limiting the infarct zone. However, the results of some clinical trials are inconsistent, since they reported no benefit of MR antagonists in acute myocardial infarction. Due to this, further studies and the results of ongoing clinical trials regarding MR antagonist administration in patients with acute myocardial infarction are being awaited with great interest.

Measurement of left ventricular end-diastolic pressure improves the prognostic utility of the Global Registry of Acute Coronary Events score in patients with ST-segment elevation myocardial infarction

AIMS

This study aimed to evaluate the clinical significance of measuring left ventricular end-diastolic pressure (LVEDP) in patients with ST-segment elevation myocardial infarction (STEMI).

METHODS AND RESULTS

We retrospectively analysed clinical data from 277 patients with STEMI between October 2006 and June 2014. LVEDP and left ventricular ejection fraction (LVEF) were perioperatively measured during percutaneous coronary intervention (PCI). The primary endpoint was a major adverse cardiac event (MACE) such as cardiac death, non-fatal myocardial infarction, or hospitalisation due to heart failure during the observation period. The independent predictors were identified by Cox proportional hazards regression analysis. Continuous net reclassification improvement (cNRI) and integrated discrimination improvement (IDI) were conducted to assess the incremental prognostic value of adding cardiovascular parameters, including LVEDP, to the Global Registry of Acute Coronary Events (GRACE) score. The mean follow-up period was 44±31 months. A MACE occurred in 33 patients (12.0%). In the Cox proportional hazards regression model, after adjusting for confounding factors, LVEDP was an independent predictor of a MACE (hazard ratio [HR] 1.11, 95% confidence interval [CI]: 1.06-1.17, p<0.001). In addition, the predictive value of the GRACE score for a MACE was significantly improved by LVEDP (NRI 0.66, 95% CI: 0.32-1.01, p<0.001; IDI 0.06, 95% CI: 0.02-0.11, p=0.001), but not by LVEF (NRI 0.14, 95% CI: -0.22-0.50, p=0.44; IDI 0.01, 95% CI: 0.00-0.03, p=0.11).

CONCLUSIONS

The results of this study demonstrated that evaluating LVEDP provides an additive prognostic value over conventional risks estimated by the GRACE score among STEMI patients.

Mineralocorticoid receptor antagonists in patients with acute myocardial infarction - A systematic review and meta-analysis of randomized trials

BACKGROUND

Although mineralocorticoid antagonists (MRAs) reduce mortality in patients with heart failure complicating myocardial infarction (MI), it is unclear if they could be beneficial to all patients with MI. To evaluate the utility of MRAs in MI patients, we performed a systematic review and meta-analysis.

METHODS

MEDLINE, EMBASE, and Cochrane CENTRAL were searched from 1965 to June 2016. Conference abstracts were searched from 2000 to June 2016. Randomized trials evaluating the effect of MRA after MIs were included. Two reviewers independently extracted data and assessed study quality. Data were combined using fixed-/random-effects models.

RESULTS

Eleven randomized clinical trials (N = 11,258) were included; 1 trial (N = 6,642) included patients with apparent heart failure (Killip class III-IV). Administration of MRA versus placebo or standard therapy (no-MRA) after MI reduced overall and cardiovascular mortality (odds ratio [OR] 0.82, 95% CI 0.73-0.93, P = .002, and OR 0.82, 95% CI 0.71-0.93, P = .003, respectively; I² for both = 0%). In the subgroup of trials with patients with heart failure, the mortality was 14.4% in MRA group versus 16.7% in no-MRA group (OR 0.84, 95% CI 0.73-0.96), and among those without heart failure, it was 2.5% with MRA versus 3.5% without MRA (OR 0.72, 95% CI 0.51-1.02, P for interaction = .43). Patients receiving MRA had fewer new or worsening heart failure events (OR 0.74, 95% CI 0.66-0.84, P < .0001; I² = 14%). Nevertheless, MRA therapy increased risk for hyperkalemia (≥5.5 mmol/L) (OR 2.52, 95% CI 1.36-4.65, P = .003; I² = 63%).

CONCLUSIONS

Administration of MRA may reduce mortality after acute MI. However, this is largely based on post-MI patients with heart failure. Further data are needed in MI patients without heart failure.