VALIANT (VALsartan In Acute myocardial iNfarcTion) trial

Implantable Cardioverter Defibrillator in Primary and Secondary Prevention of SCD-What We Still Don't Know

Implantable cardioverter defibrillators (ICDs) are the cornerstone of primary and secondary prevention of sudden cardiac death (SCD) all around the globe. In almost 40 years of technological advances and multiple clinical trials, there has been a continuous increase in the implantation rate. The purpose of this review is to highlight the grey areas related to actual ICD recommendations, focusing specifically on the primary prevention of SCD. We will discuss the still-existing controversies strongly reflected in the differences between the international guidelines regarding ICD indication class in non-ischemic cardiomyopathy, and also address the question of early implantation after myocardial infarction in the absence of clear protocols for patients at high risk of life-threatening arrhythmias. Correlating the insufficient data in the literature for 40-day waiting times with the increased risk of SCD in the first month after myocardial infarction, we review the pros and cons of early ICD implantation.

Pharmacological interventions for heart failure in people with chronic kidney disease

BACKGROUND

Approximately half of people with heart failure have chronic kidney disease (CKD). Pharmacological interventions for heart failure in people with CKD have the potential to reduce death (any cause) or hospitalisations for decompensated heart failure. However, these interventions are of uncertain benefit and may increase the risk of harm, such as hypotension and electrolyte abnormalities, in those with CKD.

OBJECTIVES

This review aims to look at the benefits and harms of pharmacological interventions for HF (i.e., antihypertensive agents, inotropes, and agents that may improve the heart performance indirectly) in people with HF and CKD.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies through 12 September 2019 in consultation with an Information Specialist and using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

We included randomised controlled trials of any pharmacological intervention for acute or chronic heart failure, among people of any age with chronic kidney disease of at least three months duration.

DATA COLLECTION AND ANALYSIS

Two authors independently screened the records to identify eligible studies and extracted data on the following dichotomous outcomes: death, hospitalisations, worsening heart failure, worsening kidney function, hyperkalaemia, and hypotension. We used random effects meta-analysis to estimate treatment effects, which we expressed as a risk ratio (RR) with 95% confidence intervals (CI). We assessed the risk of bias using the Cochrane tool. We applied the GRADE methodology to rate the certainty of evidence.

MAIN RESULTS

One hundred and twelve studies met our selection criteria: 15 were studies of adults with CKD; 16 studies were conducted in the general population but provided subgroup data for people with CKD; and 81 studies included individuals with CKD, however, data for this subgroup were not provided. The risk of bias in all 112 studies was frequently high or unclear. Of the 31 studies (23,762 participants) with data on CKD patients, follow-up ranged from three months to five years, and study size ranged from 16 to 2916 participants. In total, 26 studies (19,612 participants) reported disaggregated and extractable data on at least one outcome of interest for our review and were included in our meta-analyses. In acute heart failure, the effects of adenosine A1-receptor antagonists, dopamine, nesiritide, or serelaxin on death, hospitalisations, worsening heart failure or kidney function, hyperkalaemia, hypotension or quality of life were uncertain due to sparse data or were not reported. In chronic heart failure, the effects of angiotensin-converting enzyme inhibitors (ACEi) or angiotensin receptor blockers (ARB) (4 studies, 5003 participants: RR 0.85, 95% CI 0.70 to 1.02; I2 = 78%; low certainty evidence), aldosterone antagonists (2 studies, 34 participants: RR 0.61 95% CI 0.06 to 6.59; very low certainty evidence), and vasopressin receptor antagonists (RR 1.26, 95% CI 0.55 to 2.89; 2 studies, 1840 participants; low certainty evidence) on death (any cause) were uncertain. Treatment with beta-blockers may reduce the risk of death (any cause) (4 studies, 3136 participants: RR 0.69, 95% CI 0.60 to 0.79; I2 = 0%; moderate certainty evidence). Treatment with ACEi or ARB (2 studies, 1368 participants: RR 0.90, 95% CI 0.43 to 1.90; I2 = 97%; very low certainty evidence) had uncertain effects on hospitalisation for heart failure, as treatment estimates were consistent with either benefit or harm. Treatment with beta-blockers may decrease hospitalisation for heart failure (3 studies, 2287 participants: RR 0.67, 95% CI 0.43 to 1.05; I2 = 87%; low certainty evidence). Aldosterone antagonists may increase the risk of hyperkalaemia compared to placebo or no treatment (3 studies, 826 participants: RR 2.91, 95% CI 2.03 to 4.17; I2 = 0%; low certainty evidence). Renin inhibitors had uncertain risks of hyperkalaemia (2 studies, 142 participants: RR 0.86, 95% CI 0.49 to 1.49; I2 = 0%; very low certainty). We were unable to estimate whether treatment with sinus node inhibitors affects the risk of hyperkalaemia, as there were few studies and meta-analysis was not possible. Hyperkalaemia was not reported for the CKD subgroup in studies investigating other therapies. The effects of ACEi or ARB, or aldosterone antagonists on worsening heart failure or kidney function, hypotension, or quality of life were uncertain due to sparse data or were not reported. Effects of anti-arrhythmic agents, digoxin, phosphodiesterase inhibitors, renin inhibitors, sinus node inhibitors, vasodilators, and vasopressin receptor antagonists were very uncertain due to the paucity of studies.

AUTHORS' CONCLUSIONS

The effects of pharmacological interventions for heart failure in people with CKD are uncertain and there is insufficient evidence to inform clinical practice. Study data for treatment outcomes in patients with heart failure and CKD are sparse despite the potential impact of kidney impairment on the benefits and harms of treatment. Future research aimed at analysing existing data in general population HF studies to explore the effect in subgroups of patients with CKD, considering stage of disease, may yield valuable insights for the management of people with HF and CKD.

Comparison of short-term clinical outcomes of proximal versus nonproximal lesion location in patients treated with primary percutaneous coronary intervention for ST-elevation myocardial infarction: The PROXIMITI study

OBJECTIVES

The objective of this study was to investigate the association of proximal and nonproximal location of culprit coronary lesions with clinical outcomes of patients presenting with ST-elevation myocardial infarction (STEMI) treated by primary percutaneous coronary intervention (PCI).

BACKGROUND

Proximal culprit lesion location in patients presenting with STEMI is associated with increased mortality when compared to distal culprit lesions in the thrombolytic era. The impact of lesion location on clinical outcomes in the era of PCI remains unclear.

METHODS

We analyzed 3,283 patients with STEMI who enrolled in the Victorian Cardiac Outcomes Registry. We compared outcomes in those with proximal lesion location versus patients with nonproximal location.

RESULTS

Of 3,283 participants, 1,376 (41.9%) had a proximal lesion location. Patients with proximal lesion location presented with greater rates of cardiogenic shock and out-of-hospital cardiac arrest, and left ventricular systolic dysfunction, all P < .01. Procedural success rates were similar (96% vs. 95%, P = .08). Patients with proximal lesion location had higher rates of in-hospital and 30-day mortality, major adverse cardiac events (MACE; mortality, myocardial infarction, stent thrombosis, and unplanned revascularization) and major adverse cardiac and cerebrovascular events (MACCE; MACE, and stroke) compared to the nonproximal group, all P < .001. However, on multivariable regression analysis, proximal lesion location was not independently associated with MACE during in-hospital stay or at 30-days (OR 1.32, 95% CI 0.95-1.83, P = .09 and OR 1.23, 95% CI 0.92-1.65, P = .15) respectively.

CONCLUSIONS

Patients with proximal lesion location had greater hemodynamic instability and higher-risk features; however, proximal lesions per se were not independently associated with worse clinical outcomes compared to nonproximal lesions.

Examining the Association of Olmesartan and Other Angiotensin Receptor Blockers With Overall and Cause-Specific Mortality

Concerns about an increased cardiovascular risk with the angiotensin receptor blocker, olmesartan, prompted the current study to examine associations between olmesartan and other angiotensin receptor blockers with overall and cause-specific mortalities. We collected patients who started to use losartan, valsartan, irbesartan, candesartan, telmisartan, and olmesartan between January 1, 2004, and December 31, 2009, from Taiwan’s National Health Insurance claims database. Prescribed drug types, dosage, and other clinical information were collected. Overall mortality and cause-specific mortality were ascertained through linkages with Taiwan’s National Death Registry. Two follow-up analyses, labeled intention-to-treat and as-treated, were conducted. A Cox proportional hazard regression model was used to calculate the hazard ratio (HR) and 95% confidence interval (CI) using losartan as the reference group. A total of 690 463 subjects were included, with a mean follow-up ranging from a low of 2.8 years for olmesartan to a high of 4.1 years for irbesartan. Subjects who began with valsartan had a modest but significantly increased risk of overall mortality (HR, 1.04; 95% CI, 1.02–1.06) compared with losartan. Irbesartan (HR, 0.96; 95% CI, 0.94–0.99), candesartan (HR, 0.95; 95% CI, 0.92–0.99), telmisartan (HR, 0.93; 95% CI, 0.90–0.96), and olmesartan (HR, 0.93; 95% CI, 0.88–0.97) were associated with a slightly lower overall mortality risk than losartan. The analysis indicates that the differences in mortality risk among individual angiotensin receptor blockers were only marginal and thus less likely to be clinically important. Although uncontrolled confounding might still exist, olmesartan does not seem to increase cardiovascular risk compared with losartan.

Cardiac biomarkers in acute myocardial infarction

Each year, a large number of patients are seen in the Emergency Department with presentations necessitating investigation for possible acute myocardial infarction. Patients can be stratified by symptoms, risk factors and electrocardiogram results but cardiac biomarkers also have a prime role both diagnostically and prognostically. This review summarizes both the history of cardiac biomarkers as well as currently available (established and novel) assays. Cardiac troponin, our current "gold standard" biomarker criterion for the diagnosis of myocardial infarction has high sensitivity and specificity for this diagnosis and therapies instituted in patients with elevated troponin have been shown to influence outcomes. Other markers of myocardial necrosis, inflammation and neurohormonal activity have also been shown to have either diagnostic or prognostic utility, but none have been shown to be superior to troponin. The measurement of multiple biomarkers and the use of point of care markers may accelerate current diagnostic protocols for the assessment of such patients.

Retrospective analysis of real-world efficacy of angiotensin receptor blockers versus other classes of antihypertensive agents in blood pressure management

BACKGROUND

Efficacy of blood pressure (BP) lowering may differ between clinical trials and what is observed in clinical practice. These differences may contribute to poor BP control rates among those at risk.

OBJECTIVE

We conducted an observational study to determine the BP-lowering efficacy of angiotensin receptor blocker (ARB) versus non-ARB-based antihypertensive treatments in a large Canadian primary care database.

METHODS

We analyzed the South Western Ontario database of 170,000 adults (aged >18 years) with hypertension persisting with antihypertensive medication for ≥9 months. Routine standard of care office BP was measured using approved manual aneroid or automated devices. BP <140 mm Hg and/or <90 mm Hg ≤9 months after treatment initiation, persistence (presence of initial antihypertensive prescription at the first, second, third, and fourth year anniversary) with antihypertensive therapy, and the presence of a cardiovascular (CV) event (ie, myocardial infarction) were studied.

RESULTS

After 9 months of monotherapy, 28% (978 of 3490) of patients on ARBs achieved target BP versus 27% (839 of 3110) on angiotensin-converting enzyme inhibitors (ACEIs) (P > 0.05), 26% (265 of 1020) on calcium channel blockers (CCBs) (P > 0.05), 21% (221 of 1050) on β-blockers (P = 0.002), and 19% (276 of 1450) on diuretics (P = 0.001). Attainment rates were significantly higher with irbesartan (38%; 332 of 873) versus losartan (32%; 335 of 1047; P = 0.01), valsartan (19%; 186 of 977; P = 0.001), and candesartan (25%; 148 of 593; P = 0.001). BP goal attainment rates were significantly higher when ARB was compared with non-ARB-based dual therapy (39%; 1007 of 2584 vs 31%; 1109 of 3576; P = 0.004); irbesartan + hydrochlorothiazide (HCTZ) was significantly higher than losartan + HCTZ (36%; 500 of 1390 vs 20%; 252 of 1261; P = 0.001). For patients receiving dual or tri-therapy, 48% (667 of 1390) of patients receiving irbesartan reached target BP versus 41% to 42% for losartan (517 of 1261), valsartan (194 of 462), and candesartan (168 of 401) (P = 0.001 for each). After 4 years, persistence rates were not statistically different among ARB, CCB, and diuretic monotherapies, but appeared somewhat higher with ACEIs and β-blockers (78%, 78%, 79%, 91%, and 84%, respectively). Persistence was not significantly different between irbesartan and losartan monotherapy (76% for both; P > 0.05), but was significantly higher with irbesartan + HCTZ versus losartan + HCTZ (96% vs 73%, respectively; P = 0.001). Patients treated with ARBs reported fewer CV events than those receiving ACEIs or CCBs (4.3% vs 7.0% and 11.0%, respectively; P < 0.001). Within the ARB class, the lowest rate was with irbesartan (3.0% vs 4.6%-5.0% for other ARBs; P < 0.02).

CONCLUSIONS

In this real-world setting, hypertensive adults treated with ARBs versus β-blockers or diuretics were more likely to have evidence-based target BP recorded. In addition, patients using ARBs versus ACEIs or CCBs had fewer reports of CV events.

Valsartan combination therapy in the management of hypertension - patient perspectives and clinical utility

The morbidity and mortality benefits of lowering blood pressure (BP) in hypertensive patients are well established, with most individuals requiring multiple agents to achieve BP control. Considering the important role of the renin-angiotensin-aldosterone system (RAAS) in the pathophysiology of hypertension, a key component of combination therapy should include a RAAS inhibitor. Angiotensin receptor blockers (ARBs) lower BP, reduce cardiovascular risk, provide organ protection, and are among the best tolerated class of antihypertensive therapy. In this article, we discuss two ARB combinations (valsartan/hydrochlorothiazide [HCTZ] and amlodipine/valsartan), both of which are indicated for the treatment of hypertension in patients not adequately controlled on monotherapy and as initial therapy in patients likely to need multiple drugs to achieve BP goals. Randomized, double-blind studies that have assessed the antihypertensive efficacy and safety of these combinations in the first-line treatment of hypertensive patients are reviewed. Both valsartan/HCTZ and amlodipine/valsartan effectively lower BP and are well tolerated in a broad range of patients with hypertension, including difficult-to-treat populations such as those with severe BP elevations, prediabetes and diabetes, patients with the cardiometabolic syndrome, and individuals who are obese, elderly, or black. Also discussed herein are patient-focused perspectives related to the use of valsartan/HCTZ and amlodipine/valsartan, and the rationale for use of single-pill combinations as one approach to enhance patient compliance with antihypertensive therapy.

Angiotensin receptor blockers: current status and future prospects

Angiotensin receptor blockers (ARBs), through their physiological blockade of the renin-angiotensin system, reduce morbidity and mortality associated with hypertension, heart failure, myocardial infarction, stroke, diabetic nephropathy, and chronic kidney disease. Among many attributes, excellent tolerability, and their ability to control hypertension for 24 hours with a positive effect on renal function position them as a useful choice for hypertension and related conditions. Because of the widespread actions of the renin-angiotensin system on critical tissues, treatment with ARBs may be beneficial in special populations. Ongoing and future studies will be needed to conclusively determine if ARBs also improve outcomes in patients with heart failure and preserved systolic function, atrial fibrillation, cognitive dysfunction, and kidney transplant recipients. Preliminary clinical data also suggest that combining ARBs and angiotensin-converting enzyme inhibitors may provide a more optimal blockade of the renin-angiotensin system and, therefore, may offer greater cardio- and nephroprotection. Future data will help delineate which ARBs and angiotensin-converting enzyme inhibitors are best combined and which patient populations might benefit from the dual blockade of the renin-angiotensin system.

An update on non-peptide angiotensin receptor antagonists and related RAAS modulators

The renin-angiotensin-aldosterone-system (RAAS) is an important regulator of blood pressure and fluid-electrolyte homeostasis. RAAS has been implicated in pathogenesis of hypertension, congestive heart failure, and chronic renal failure. Aliskiren is the first non-peptide orally active renin inhibitor approved by FDA. Angiotensin Converting Enzyme (ACE) Inhibitors are associated with frequent side effects such as cough and angio-oedema. Recently, the role of ACE2 and neutral endopeptidase (NEP) in the formation of an important active metabolite/mediator of RAAS, ang 1-7, has initiated attempts towards development of ACE2 inhibitors and combined ACE/NEP inhibitors. Furukawa and colleagues developed a series of low molecular weight nonpeptide imidazole analogues that possess weak but selective, competitive AT1 receptor blocking property. Till date, many compounds have exhibited promising AT1 blocking activity which cause a more complete RAAS blockade than ACE inhibitors. Many have reached the market for alternative treatment of hypertension, heart failure and diabetic nephropathy in ACE inhibitor intolerant patients and still more are waiting in the queue. But, the hallmark of this area of drug research is marked by a progress in understanding molecular interaction of these blockers at the AT1 receptor and unraveling the enigmatic influence of AT2 receptors on growth/anti-growth, differentiation and the regeneration of neuronal tissue. Different modeling strategies are underway to develop tailor made molecules with the best of properties like Dual Action (Angiotensin And Endothelin) Receptor Antagonists (DARA), ACE/NEP inhibitors, triple inhibitors, AT2 agonists, AT1/TxA2 antagonists, balanced AT1/AT2 antagonists, and nonpeptide renin inhibitors. This abstract gives an overview of these various angiotensin receptor antagonists.