Dapagliflozin in Patients with Heart Failure and Reduced Ejection Fraction

BACKGROUND

In patients with type 2 diabetes, inhibitors of sodium-glucose cotransporter 2 (SGLT2) reduce the risk of a first hospitalization for heart failure, possibly through glucose-independent mechanisms. More data are needed regarding the effects of SGLT2 inhibitors in patients with established heart failure and a reduced ejection fraction, regardless of the presence or absence of type 2 diabetes.

METHODS

In this phase 3, placebo-controlled trial, we randomly assigned 4744 patients with New York Heart Association class II, III, or IV heart failure and an ejection fraction of 40% or less to receive either dapagliflozin (at a dose of 10 mg once daily) or placebo, in addition to recommended therapy. The primary outcome was a composite of worsening heart failure (hospitalization or an urgent visit resulting in intravenous therapy for heart failure) or cardiovascular death.

RESULTS

Over a median of 18.2 months, the primary outcome occurred in 386 of 2373 patients (16.3%) in the dapagliflozin group and in 502 of 2371 patients (21.2%) in the placebo group (hazard ratio, 0.74; 95% confidence interval [CI], 0.65 to 0.85; P<0.001). A first worsening heart failure event occurred in 237 patients (10.0%) in the dapagliflozin group and in 326 patients (13.7%) in the placebo group (hazard ratio, 0.70; 95% CI, 0.59 to 0.83). Death from cardiovascular causes occurred in 227 patients (9.6%) in the dapagliflozin group and in 273 patients (11.5%) in the placebo group (hazard ratio, 0.82; 95% CI, 0.69 to 0.98); 276 patients (11.6%) and 329 patients (13.9%), respectively, died from any cause (hazard ratio, 0.83; 95% CI, 0.71 to 0.97). Findings in patients with diabetes were similar to those in patients without diabetes. The frequency of adverse events related to volume depletion, renal dysfunction, and hypoglycemia did not differ between treatment groups.

CONCLUSIONS

Among patients with heart failure and a reduced ejection fraction, the risk of worsening heart failure or death from cardiovascular causes was lower among those who received dapagliflozin than among those who received placebo, regardless of the presence or absence of diabetes. (Funded by AstraZeneca; DAPA-HF ClinicalTrials.gov number, NCT03036124.).

Dapagliflozin in Heart Failure with Mildly Reduced or Preserved Ejection Fraction

BACKGROUND

Sodium-glucose cotransporter 2 (SGLT2) inhibitors reduce the risk of hospitalization for heart failure and cardiovascular death among patients with chronic heart failure and a left ventricular ejection fraction of 40% or less. Whether SGLT2 inhibitors are effective in patients with a higher left ventricular ejection fraction remains less certain.

METHODS

We randomly assigned 6263 patients with heart failure and a left ventricular ejection fraction of more than 40% to receive dapagliflozin (at a dose of 10 mg once daily) or matching placebo, in addition to usual therapy. The primary outcome was a composite of worsening heart failure (which was defined as either an unplanned hospitalization for heart failure or an urgent visit for heart failure) or cardiovascular death, as assessed in a time-to-event analysis.

RESULTS

Over a median of 2.3 years, the primary outcome occurred in 512 of 3131 patients (16.4%) in the dapagliflozin group and in 610 of 3132 patients (19.5%) in the placebo group (hazard ratio, 0.82; 95% confidence interval [CI], 0.73 to 0.92; P<0.001). Worsening heart failure occurred in 368 patients (11.8%) in the dapagliflozin group and in 455 patients (14.5%) in the placebo group (hazard ratio, 0.79; 95% CI, 0.69 to 0.91); cardiovascular death occurred in 231 patients (7.4%) and 261 patients (8.3%), respectively (hazard ratio, 0.88; 95% CI, 0.74 to 1.05). Total events and symptom burden were lower in the dapagliflozin group than in the placebo group. Results were similar among patients with a left ventricular ejection fraction of 60% or more and those with a left ventricular ejection fraction of less than 60%, and results were similar in prespecified subgroups, including patients with or without diabetes. The incidence of adverse events was similar in the two groups.

CONCLUSIONS

Dapagliflozin reduced the combined risk of worsening heart failure or cardiovascular death among patients with heart failure and a mildly reduced or preserved ejection fraction. (Funded by AstraZeneca; DELIVER ClinicalTrials.gov number, NCT03619213.).

Effect of Dapagliflozin on Worsening Heart Failure and Cardiovascular Death in Patients With Heart Failure With and Without Diabetes

IMPORTANCE

Additional treatments are needed for heart failure with reduced ejection fraction (HFrEF). Sodium-glucose cotransporter 2 (SGLT2) inhibitors may be an effective treatment for patients with HFrEF, even those without diabetes.

OBJECTIVE

To evaluate the effects of dapagliflozin in patients with HFrEF with and without diabetes.

DESIGN, SETTING, AND PARTICIPANTS

Exploratory analysis of a phase 3 randomized trial conducted at 410 sites in 20 countries. Patients with New York Heart Association classification II to IV with an ejection fraction less than or equal to 40% and elevated plasma N-terminal pro B-type natriuretic peptide were enrolled between February 15, 2017, and August 17, 2018, with final follow-up on June 6, 2019.

INTERVENTIONS

Addition of once-daily 10 mg of dapagliflozin or placebo to recommended therapy.

MAIN OUTCOMES AND MEASURES

The primary outcome was the composite of an episode of worsening heart failure or cardiovascular death. This outcome was analyzed by baseline diabetes status and, in patients without diabetes, by glycated hemoglobin level less than 5.7% vs greater than or equal to 5.7%.

RESULTS

Among 4744 patients randomized (mean age, 66 years; 1109 [23%] women; 2605 [55%] without diabetes), 4742 completed the trial. Among participants without diabetes, the primary outcome occurred in 171 of 1298 (13.2%) in the dapagliflozin group and 231 of 1307 (17.7%) in the placebo group (hazard ratio, 0.73 [95% CI, 0.60-0.88]). In patients with diabetes, the primary outcome occurred in 215 of 1075 (20.0%) in the dapagliflozin group and 271 of 1064 (25.5%) in the placebo group (hazard ratio, 0.75 [95% CI, 0.63-0.90]) (P value for interaction = .80). Among patients without diabetes and a glycated hemoglobin level less than 5.7%, the primary outcome occurred in 53 of 438 patients (12.1%) in the dapagliflozin group and 71 of 419 (16.9%) in the placebo group (hazard ratio, 0.67 [95% CI, 0.47-0.96]). In patients with a glycated hemoglobin of at least 5.7%, the primary outcome occurred in 118 of 860 patients (13.7%) in the dapagliflozin group and 160 of 888 (18.0%) in the placebo group (hazard ratio, 0.74 [95% CI, 0.59-0.94]) (P value for interaction = .72). Volume depletion was reported as an adverse event in 7.3% of patients in the dapagliflozin group and 6.1% in the placebo group among patients without diabetes and in 7.8% of patients in the dapagliflozin group and 7.8% in the placebo group among patients with diabetes. A kidney adverse event was reported in 4.8% of patients in the dapagliflozin group and 6.0% in the placebo group among patients without diabetes and in 8.5% of patients in the dapagliflozin group and 8.7% in the placebo group among patients with diabetes.

CONCLUSIONS AND RELEVANCE

In this exploratory analysis of a randomized trial of patients with HFrEF, dapagliflozin compared with placebo, when added to recommended therapy, significantly reduced the risk of worsening heart failure or cardiovascular death independently of diabetes status.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03036124.

Distribution and risk profile of paroxysmal, persistent, and permanent atrial fibrillation in routine clinical practice: insight from the real-life global survey evaluating patients with atrial fibrillation international registry

BACKGROUND

There is a paucity of international data on the various types of atrial fibrillation (AF) outside the highly selected populations from randomized trials. This study aimed to describe patient characteristics, risk factors, comorbidities, symptoms, management strategy, and control of different types of AF in real-life practice.

METHODS AND RESULTS

Real-life global survey evaluating patients with atrial fibrillation (RealiseAF) was a contemporary, large-scale, cross-sectional international survey of patients with AF who had ≥1 episode in the past 12 months. Investigators were randomly selected to avoid bias. Among 9816 eligible patients from 831 sites in 26 countries, 2606 (26.5%) had paroxysmal, 2341 (23.8%) had persistent, and 4869 (49.6%) had permanent AF. As AF progressed from paroxysmal to persistent and permanent forms, the prevalence of comorbidities, such as heart failure (32.9%, 44.3%, and 55.6%), coronary artery disease (30.0%, 32.9%, and 34.3%), cerebrovascular disease (11.7%, 10.8%, and 17.6%), and valvular disease (16.7%, 21.2%, and 35.8%), increased, and the prevalence of lone AF decreased. Similarly, there was an increase in mean CHADS(2) [cardiac failure, hypertension, age, diabetes, stroke (doubled)] score (1.7, 1.8, and 2.2), and more than half of patients (51.0%, 56.7%, and 67.3%) qualified for oral anticoagulants. Almost 90% of patients received ≥1 antiarrhythmic drug, but >60% had European Heart Rhythm Association symptom scores from II to IV. Furthermore, 40.7% of persistent and 49.8% of permanent AF patients were still in AF with a heart rate >80 beats per minute.

CONCLUSIONS

This survey disclosed high cardiovascular risks and an unmet need in daily practice for patients with any type of AF, especially those with the permanent form.

Sustained atrial tachycardia in adult patients. Electrophysiological characteristics, pharmacological response, possible mechanisms, and effects of radiofrequency ablation

BACKGROUND

Mechanisms and electropharmacological characteristics in adult patients with atrial tachycardia (AT) are not well described. We proposed that a combination of electropharmacological characteristics, recording of monophasic action potential, and effects of radiofrequency ablation could further determine the mechanisms and achieve a new classification in adults with various types of AT because they were important in regard to the correlation between mechanisms and pathophysiology, clinical syndrome, and responses to specific pharmacological or nonpharmacological therapies.

METHODS AND RESULTS

Thirty-six patients (11 female, 25 male; mean age, 57 +/- 13 years) with AT were referred for electropharmacological studies and radiofrequency ablation. Resetting response pattern, entrainment phenomenon, recording of monophasic action potential, serial drug test, response to Valsalva maneuver, endocardial mapping technique, and radiofrequency ablation were performed. Seven patients had automatic AT provocable with isoproterenol; neither initiation nor termination was related to programmed electrical stimulation. The other 29 patients had AT initiated or terminated by electrical stimulation and mechanisms related to triggered activity or reentry; nine of them needed isoproterenol to facilitate initiation of AT, associated with delayed afterdepolarization in monophasic action potential. All responded to adenosine (15 to 60 micrograms/kg) and Valsalva maneuver. Dipyridamole terminated AT and decreased the slope of afterdepolarization. Afterdepolarization was not found in the patients with automatic or reentrant AT. In 40 of 41 (98%), AT was ablated successfully, with late recurrence in 2 of 40 (5%) (follow-up, 18 +/- 4 months).

CONCLUSIONS

This study demonstrates the diverse mechanisms and electropharmacological characteristics of AT in adults. Furthermore, radiofrequency ablation of various types of AT could achieve high success and low recurrence rates.

Stroke prevention in atrial fibrillation: An Asian perspective

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. In 2050, it is estimated that there will be 72 million AF patients in Asia, accounting for almost 2.9 million patients suffering from AF-associated stroke. Asian AF patients share similar risk factor profiles as non-Asians, except that more Asians have a history of previous stroke. Clinical challenges are evident in the field of stroke prevention in AF, amongst Asians. Existing stroke and bleeding risk scores have not been well-validated in Asians. Asians are prone to bleeding when treated with warfarin, and the optimal international normalised ratio (INR) for warfarin use is yet to be determined in Asians, though Asian physicians tend to keep it in a lower range (e.g. INR 1.6–2.6) for elderly patients despite limited evidence to justify this. In general, warfarin is ‘difficult’ to use in Asians due to higher risk of bleeding and higher stroke rate in Asians than in non-Asians, as shown in randomised controlled trials. Excess of bleeding was not found in Asians when novel oral anticoagulants (NOACs) were used. Besides, the superiority of NOACs to warfarin in reducing thromboembolism was maintained in Asians. Therefore NOACs are preferentially indicated in Asians in terms of both efficacy and safety. Also, some preliminary data suggest that Asian patients with AF might not be the same. Future prospective randomised trials are needed for the selection of NOACs according to different ethnic background.

Note: The review process for this manuscript was fully handled by Christian Weber, Editor in Chief.

The long QT syndromes: genetic basis and clinical implications

It is becoming clear that mutations in the KVLQT1, human "ether-a-go-go" related gene, cardiac voltage-dependent sodium channel gene, minK and MiRP1 genes, respectively, are responsible for the LQT1, LQT2, LQT3, LQT5 and LQT6 variants of the Romano-Ward syndrome, characterized by autosomal dominant transmission and no deafness. The much rarer Jervell-Lange-Nielsen syndrome (with marked QT prolongation and sensorineural deafness) arises when a child inherits mutant KVLQT1 or minK alleles from both parents. In addition, some families are not linked to the known genetic loci. Cardiac voltage-dependent sodium channel gene encodes the cardiac sodium channel, and long QT syndrome (LQTS) mutations prolong action potentials by increasing inward plateau sodium current. The other mutations cause a decrease in net repolarizing current by reducing potassium currents through "dominant negative" or "loss of function" mechanisms. Polymorphic ventricular tachycardia (torsade de pointes) is thought to be initiated by early after-depolarizations in the Purkinje system and maintained by reentry in the myocardium. Clinical presentations vary with the specific gene affected and the specific mutation. Nevertheless, patients with identical mutations can also present differently, and some patients with LQTS mutations may have no manifest baseline phenotype. The question of whether the latter situation is one of high risk for administration of QT prolonging drugs or during myocardial ischemia is under active investigation. More generally, the identification of LQTS genes has provided tremendous new insights for our understanding of normal cardiac electrophysiology and its perturbation in a wide range of conditions associated with sudden death. It seems likely that the approach of applying information from the genetics of uncommon congenital syndromes to the study of common acquired diseases will be an increasingly important one in the next millennium.

Non-Vitamin K Antagonist Oral Anticoagulants for Stroke Prevention in Asian Patients With Nonvalvular Atrial Fibrillation: Meta-Analysis

BACKGROUND AND PURPOSE

The use of vitamin K antagonists (VKAs), the cornerstone treatment for stroke prevention in patients with atrial fibrillation, is limited by the perceived risk of serious bleeding in Asia. Non-VKA oral anticoagulants (NOACs) are safer alternatives. Here, we evaluate performance differences of NOACs between Asians and non-Asians.

METHODS

We compared efficacy and safety of NOACs between patients enrolled in Asian and non-Asian countries using aggregative data from phase III clinical trials. The odds ratios (ORs [95% confidence interval]) were calculated by a random effects model.

RESULTS

Comparing with VKAs, standard-dose NOACs reduced stroke or systemic embolism (OR=0.65 [0.52-0.83] versus 0.85 [0.77-0.93], P interaction= 0.045) more in Asians than in non-Asians and were safer in Asians than in non-Asians about major bleeding (OR=0.57 [0.44-0.74] versus 0.89 [0.76-1.04], P interaction=0.004), hemorrhagic stroke (OR=0.32 [0.19-0.52] versus 0.56 [0.44-0.70], P interaction=0.046) in particular, whereas gastrointestinal bleeding was significantly increased in non-Asians (OR=0.79 [0.48-1.32] versus 1.44 [1.12-1.85], P interaction=0.041). Generally, low-dose NOACs were safer than VKAs without heterogeneity in efficacy and safety between Asians and non-Asians, except for ischemic stroke, major, and gastrointestinal bleeding.

CONCLUSIONS

Our findings suggest that standard-dose NOACs were more effective and safer in Asians than in non-Asians, whereas low-dose NOACs performed similarly in both populations.

2015 guidelines of the Taiwan Society of Cardiology and the Taiwan Hypertension Society for the management of hypertension

It has been almost 5 years since the publication of the 2010 hypertension guidelines of the Taiwan Society of Cardiology (TSOC). There is new evidence regarding the management of hypertension, including randomized controlled trials, non-randomized trials, post-hoc analyses, subgroup analyses, retrospective studies, cohort studies, and registries. More recently, the European Society of Hypertension (ESH) and the European Society of Cardiology (ESC) published joint hypertension guidelines in 2013. The panel members who were appointed to the Eighth Joint National Committee (JNC) also published the 2014 JNC report. Blood pressure (BP) targets have been changed; in particular, such targets have been loosened in high risk patients. The Executive Board members of TSOC and the Taiwan Hypertension Society (THS) aimed to review updated information about the management of hypertension to publish an updated hypertension guideline in Taiwan. We recognized that hypertension is the most important risk factor for global disease burden. Management of hypertension is especially important in Asia where the prevalence rate grows faster than other parts of the world. In most countries in East Asia, stroke surpassed coronary heart disease (CHD) in causing premature death. A diagnostic algorithm was proposed, emphasizing the importance of home BP monitoring and ambulatory BP monitoring for better detection of night time hypertension, early morning hypertension, white-coat hypertension, and masked hypertension. We disagreed with the ESH/ESH joint hypertension guidelines suggestion to loosen BP targets to <140/90 mmHg for all patients. We strongly disagree with the suggestion by the 2014 JNC report to raise the BP target to <150/90 mmHg for patients between 60-80 years of age. For patients with diabetes, CHD, chronic kidney disease who have proteinuria, and those who are receiving antithrombotic therapy for stroke prevention, we propose BP targets of <130/80 mmHg in our guidelines. BP targets are <140/90 mmHg for all other patient groups, except for patients ≥80 years of age in whom a BP target of <150/90 mmHg would be optimal. For the management of hypertension, we proposed a treatment algorithm, starting with life style modification (LSM) including S-ABCDE (Sodium restriction, Alcohol limitation, Body weight reduction, Cigarette smoke cessation, Diet adaptation, and Exercise adoption). We emphasized a low-salt strategy instead of a no-salt strategy, and that excessively aggressive sodium restriction to <2.0 gram/day may be harmful. When drug therapy is considered, a strategy called "PROCEED" was suggested (Previous experience, Risk factors, Organ damage, Contraindications or unfavorable conditions, Expert's or doctor's judgment, Expenses or cost, and Delivery and compliance issue). To predict drug effects in lowering BP, we proposed the "Rule of 10" and "Rule of 5". With a standard dose of any one of the 5 major classes of anti-hypertensive agents, one can anticipate approximately a 10-mmHg decrease in systolic BP (SBP) (Rule of 10) and a 5-mmHg decrease in diastolic BP (DBP) (Rule of 5). When doses of the same drug are doubled, there is only a 2-mmHg incremental decrease in SBP and a 1-mmHg incremental decrease in DBP. Preferably, when 2 drugs with different mechanisms are to be taken together, the decrease in BP is the sum of the decrease of the individual agents (approximately 20 mmHg in SBP and 10 mmHg in DBP). Early combination therapy, especially single-pill combination (SPC), is recommended. When patient's initial treatment cannot get BP to targeted goals, we have proposed an adjustment algorithm, "AT GOALs" (Adherence, Timing of administration, Greater doses, Other classes of drugs, Alternative combination or SPC, and LSM + Laboratory tests). Treatment of hypertension in special conditions, including treatment of resistant hypertension, hypertension in women, and perioperative management of hypertension, were also mentioned. The TSOC/THS hypertension guidelines provide the most updated information available in the management of hypertension. The guidelines are not mandatory, and members of the task force fully realize that treatment of hypertension should be individualized to address each patient's circumstances. Ultimately, the decision of the physician decision remains of the utmost importance in hypertension management.

2017 consensus of the Asia Pacific Heart Rhythm Society on stroke prevention in atrial fibrillation

Atrial fibrillation (AF) is the most common sustained arrhythmia, causing a 2-fold increase in mortality and a 5-fold increase in stroke. The Asian population is rapidly aging, and in 2050, the estimated population with AF will reach 72 million, of whom 2.9 million may suffer from AF-associated stroke. Therefore, stroke prevention in AF is an urgent issue in Asia. Many innovative advances in the management of AF-associated stroke have emerged recently, including new scoring systems for predicting stroke and bleeding risks, the development of non-vitamin K antagonist oral anticoagulants (NOACs), knowledge of their special benefits in Asians, and new techniques. The Asia Pacific Heart Rhythm Society (APHRS) aimed to update the available information, and appointed the Practice Guideline sub-committee to write a consensus statement regarding stroke prevention in AF. The Practice Guidelines sub-committee members comprehensively reviewed updated information on stroke prevention in AF, emphasizing data on NOACs from the Asia Pacific region, and summarized them in this 2017 Consensus of the Asia Pacific Heart Rhythm Society on Stroke Prevention in AF. This consensus includes details of the updated recommendations, along with their background and rationale, focusing on data from the Asia Pacific region. We hope this consensus can be a practical tool for cardiologists, neurologists, geriatricians, and general practitioners in this region. We fully realize that there are gaps, unaddressed questions, and many areas of uncertainty and debate in the current knowledge of AF, and the physician׳s decision remains the most important factor in the management of AF.

Long-term outcome of radiofrequency catheter ablation for typical atrial flutter: risk prediction of recurrent arrhythmias

INTRODUCTION

Little is known about the predictors of recurrent atrial flutter or fibrillation after successful radiofrequency ablation of typical atrial flutter. In addition, there is only limited evidence suggesting that elimination of atrial flutter would modify the natural history of atrial fibrillation in patients who experienced both of these arrhythmias. The aims of the present study were to investigate the long-term results of radiofrequency catheter ablation and to examine the predictors for late occurrence of atrial fibrillation in a large population with typical atrial flutter.

METHODS AND RESULTS

The study population consisted of 144 patients (mean age 56 +/- 18 years) with successful ablation of clinically documented typical atrial flutter. In the first 50 patients, successful ablation was defined as termination and noninducibility of atrial flutter; for the subsequent 94 patients, successful ablation was defined as achievement of bidirectional isthmus conduction block and no induction of atrial flutter. The clinical and echocardiographic variables were analyzed in relation to the late occurrence of atrial flutter or fibrillation. Over the follow-up period of 17 +/- 13 months, 14 (9.7%) patients had recurrence of typical atrial flutter. In the first 50 patients, 8 (16%) had recurrence of atrial flutter, compared with only 6 (6%) of the following 94 patients. Patients with incomplete isthmus block had a significantly higher incidence of recurrent atrial flutter than those with complete isthmus block (6/16 vs 0/78, P < 0.0001) in the following 94 patients. There was no predictor for recurrence of atrial flutter after successful ablation as determined by univariate and multivariate analysis. Although successful ablation of atrial flutter eliminated atrial fibrillation in 45% of patients with a prior history of atrial fibrillation, 31 (21.5%) of 144 patients undergoing this procedure developed atrial fibrillation during the follow-up period. Univariate analysis revealed that three clinical variables were related to the occurrence of atrial fibrillation: (1) the presence of structural heart disease; (2) a history of atrial fibrillation before ablation; and (3) inducible sustained atrial fibrillation after ablation. By multivariate analysis, only a history of atrial fibrillation and inducible sustained atrial fibrillation could predict the late development of atrial fibrillation after atrial flutter ablation.

CONCLUSION

Radiofrequency catheter ablation of typical atrial flutter is highly effective and associated with a low recurrence rate of atrial flutter, but atrial fibrillation continues to be a long-term risk for patients undergoing this procedure. The presence of structural heart disease and prior spontaneous or inducible sustained atrial fibrillation increases the risk of developing atrial fibrillation.

Efficacy and Safety of Dapagliflozin in Heart Failure With Reduced Ejection Fraction According to Age: Insights From DAPA-HF

BACKGROUND

The DAPA-HF trial (Dapagliflozin and Prevention of Adverse-Outcomes in Heart Failure) showed that dapagliflozin added to other guideline-recommended therapies reduced the risk of mortality and heart failure hospitalization and improved symptoms in patients with heart failure and reduced ejection fraction. We examined the effects of dapagliflozin according to age, given potential concerns about the efficacy and safety of therapies in the elderly.

METHODS

Patients in New York Heart Association functional class II or greater with a left ventricular ejection fraction ≤40% and a modest elevation of NT-proBNP (N-terminal pro-B-type natriuretic peptide) were eligible. Key exclusion criteria included systolic blood pressure <95 mm Hg and estimated glomerular filtration rate <30 mL·min^-1·1.73 m^-2. The primary outcome was the composite of an episode of worsening heart failure (heart failure hospitalization or urgent heart failure visit) or cardiovascular death, whichever occurred first.

RESULTS

A total of 4744 patients 22 to 94 years of age (mean age, 66.3 [SD 10.9] years) were randomized: 636 patients (13.4%) were <55 years of age, 1242 (26.2%) were 55 to 64 years of age, 1717 (36.2%) were 65 to 74 years of age, and 1149 (24.2%) were ≥75 years of age. The rate of the primary outcome (per 100 person-years, placebo arm) in each age group was 13.6 (95% CI, 10.4-17.9), 15.7 (95% CI, 13.2-18.7), 15.1 (95% CI, 13.1-17.5), and 18.0 (95% CI, 15.2-21.4) with corresponding dapagliflozin/placebo hazard ratios of 0.87 (95% CI, 0.60-1.28), 0.71 (95% CI, 0.55-0.93), 0.76 (95% CI, 0.61-0.95), and 0.68 (95% CI, 0.53-0.88; P for interaction=0.76). Consistent benefits were observed for the components of the primary outcome, all-cause mortality, and symptoms. Although adverse events and study drug discontinuation increased with age, neither was significantly more common with dapagliflozin in any age group.

CONCLUSIONS

Dapagliflozin reduced the risk of death and worsening heart failure and improved symptoms across the broad spectrum of age studied in DAPA-HF. There was no significant imbalance in tolerability or safety events between dapagliflozin and placebo, even in elderly individuals.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT03036124.

2016 Guidelines of the Taiwan Heart Rhythm Society and the Taiwan Society of Cardiology for the management of atrial fibrillation

Atrial fibrillation (AF) is the most common sustained arrhythmia. Both the incidence and prevalence of AF are increasing, and the burden of AF is becoming huge. Many innovative advances have emerged in the past decade for the diagnosis and management of AF, including a new scoring system for the prediction of stroke and bleeding events, the introduction of non-vitamin K antagonist oral anticoagulants and their special benefits in Asians, new rhythm- and rate-control concepts, optimal endpoints of rate control, upstream therapy, life-style modification to prevent AF recurrence, and new ablation techniques. The Taiwan Heart Rhythm Society and the Taiwan Society of Cardiology aimed to update the information and have appointed a jointed writing committee for new AF guidelines. The writing committee members comprehensively reviewed and summarized the literature, and completed the 2016 Guidelines of the Taiwan Heart Rhythm Society and the Taiwan Society of Cardiology for the Management of Atrial Fibrillation. This guideline presents the details of the updated recommendations, along with their background and rationale, focusing on data unique for Asians. The guidelines are not mandatory, and members of the writing committee fully realize that treatment of AF should be individualized. The physician's decision remains most important in AF management.

Focal atrial tachycardia: reanalysis of the clinical and electrophysiologic characteristics and prediction of successful radiofrequency ablation

INTRODUCTION

Reports about the clinical and electrophysiologic characteristics of focal atrial tachycardia vary widely. Furthermore, the impact of age, gender, associated cardiac diseases, mechanism, location of atrial tachycardia, and the prediction of results of radiofrequency catheter ablation was not clear. The purpose of this study was to further understand the clinical and electrophysiologic characteristics of focal atrial tachycardia and the prediction of results of radiofrequency ablation.

METHODS AND RESULTS

We searched the literature published between January 1969 and July 1997 using the key word "atrial tachycardia" from the MEDLINE and National Library of Medicine systems. The items analyzed were age, sex, cardiac disease, mechanism, attack pattern, cycle length, location, number of atrial tachycardias, results of ablation, and recurrence after ablation. Multivariate analysis showed that age and paroxysmal type of tachycardia were independent predictors of nonautomatic mechanism; age and presence of other cardiac diseases were independent predictors of multiple atrial tachycardias, and age also was the independent predictor of right-sided atrial tachycardia. Atrial tachycardia located in the right atrium was the only significant predictor of successful radiofrequency catheter ablation. Other cardiac diseases and multiple atrial tachycardias were the significant predictors of recurrence after initial successful radiofrequency catheter ablation.

CONCLUSION

Patient age is closely related to the clinical and electrophysiologic characteristics of atrial tachycardia based on our reanalysis, which found that patient age is an independent predictor of nonautomatic mechanism, right atrial location, existence of multiple atrial tachycardias, and recurrence of atrial tachycardia after initial successful ablation.

Is 8-mm more effective than 4-mm tip electrode catheter for ablation of typical atrial flutter?

BACKGROUND

The prospective, randomized study comparing 4- with 8-mm tip electrodes for radiofrequency linear ablation of typical atrial flutter is not available.

METHODS AND RESULTS

A total of 104 consecutive patients with typical atrial flutter were randomly assigned to undergo radiofrequency linear ablation using a 4- (Group I, n=54) or 8-mm tip electrode (Group II, n=50) catheter (temperature-control model, preset 70 degrees C). If complete bidirectional isthmus block could not be achieved after 5 pulses, the ablation catheter was changed to the other type; the maximal radiofrequency pulse number was limited to <10 pulses. Complete or incomplete isthmus conduction block was assessed by activation sequence in a multielectrode Halo catheter during low lateral right atrial and proximal coronary sinus pacing. Before shifting to the other catheter type, the 8-mm electrode catheter achieved higher complete isthmus block rate (92% versus 67%, P<0.05) with fewer pulses (2+/-1 versus 3+/-1, P<0.05), shorter procedure time (24+/-15 versus 31+/-12 minutes, P<0.05), and shorter fluoroscopic time (14+/-10 versus 23+/-15 minutes, P<0.05). After 5 failed ablation pulses, 12 (67%) of 18 patients in group I attained complete isthmus block by using an 8-mm tip catheter, but none of 4 patients in group II achieved complete block by changing to a 4-mm tip catheter.

CONCLUSIONS

The 8-mm tip electrodes are more effective than the standard 4-mm length electrodes in linear ablation for typical atrial flutter. This clinical benefit may be of particular value for some patients with broad and/or thick isthmus.

Effect of dapagliflozin according to baseline systolic blood pressure in the Dapagliflozin and Prevention of Adverse Outcomes in Heart Failure trial (DAPA-HF)

AIMS

Concern about hypotension often leads to withholding of beneficial therapy in patients with heart failure and reduced ejection fraction (HFrEF). We evaluated the efficacy and safety of dapagliflozin, which lowers systolic blood pressure (SBP),according to baseline SBP in Dapagliflozin and Prevention of Adverse Outcomes in Heart Failure trial (DAPA-HF).

METHODS AND RESULTS

Key inclusion criteria were: New York Heart Association Class II-IV, left ventricular ejection fraction ≤ 40%, elevated N-terminal pro-B-type natriuretic peptide level, and SBP ≥95 mmHg. The primary outcome was a composite of worsening heart failure or cardiovascular death. The efficacy and safety of dapagliflozin were examined using SBP as both a categorical and continuous variable. A total of 1205 patients had a baseline SBP <110 mmHg; 981 ≥ 110 < 120; 1149 ≥ 120 < 130; and 1409 ≥ 130 mmHg. The placebo-corrected reduction in SBP from baseline to 2 weeks with dapagliflozin was -2.54 (-3.33 to -1.76) mmHg (P < 0.001), with a smaller between-treatment difference in patients in the lowest compared to highest SBP category. Patients in the lowest SBP category had a much higher rate (per 100 person-years) of the primary outcome [20.6, 95% confidence interval (95% CI) 17.6-24.2] than those in the highest SBP category (13.8, 11.7-16.4). The benefit and safety of dapagliflozin was consistent across the range of SBP; hazard ratio (95% CI) in each SBP group, lowest to highest: 0.76 (0.60-0.97), 0.76 (0.57-1.02), 0.81 (0.61-1.08), and 0.67 (0.51-0.87), P interaction = 0.78. Study drug discontinuation did not differ between dapagliflozin and placebo across the SBP categories examined.

CONCLUSION

Dapagliflozin had a small effect on SBP in patients with HFrEF and was superior to placebo in improving outcomes, and well tolerated, across the range of SBP included in DAPA-HF.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov NCT03036124.

Statins, risk of diabetes, and implications on outcomes in the general population

OBJECTIVES

This study aimed to evaluate the association of statin exposure and incident diabetes, and subsequent outcomes in the general population.

BACKGROUND

Cardiovascular events as consequences of atherosclerosis and diabetes are reduced by statins. However, statins are associated with excessive risk of diabetes occurrence according to clinical trial analyses. From daily-practice perspectives, it remains unclear whether statin use increases risk; prognoses of diabetes after exposure require further clarification.

METHODS

From Taiwan National Health Insurance beneficiaries age ≥45 years (men) and ≥55 years (women) before 2004, subjects continuously treated with statins ≥30 days during 2000 to 2003 and nonusers before 2004 were identified. Among nondiabetic individuals at the cohort entry, controls were matched to statin users on a 4:1 ratio by age, sex, atherosclerotic comorbidities, and year of their entry. Outcomes as diabetes, major adverse cardiovascular events (MACE, the composite of myocardial infarction and ischemic stroke), and in-hospital deaths were assessed.

RESULTS

Over a median of 7.2 years, annual rates of diabetes were significantly higher in statin users (2.4% vs. 2.1%, p < 0.001), whereas MACE (hazard ratio [HR]: 0.82; 95% confidence interval [CI]: 0.68 to 0.98 for myocardial infarction; HR: 0.94; 95% CI: 0.86 to 1.03 for ischemic stroke; HR: 0.91; 95% CI: 0.84 to 0.99 for MACE]) and in-hospital mortality (HR: 0.61; 95% CI: 0.55 to 0.67]) were less. The risk-benefit analyses suggested that statin treatment was favorable in high-risk (HR: 0.89; 95% CI: 0.83 to 0.95) and secondary prevention (HR: 0.89; 95% CI: 0.83 to 0.96) populations. Among diabetic patients, prior statin use was associated with fewer MACE (HR: 0.75; 95% CI: 0.59 to 0.97). In-hospital deaths were similar in statin-related diabetes among high-risk (HR: 1.11; 95% CI: 0.83 to 1.49) and secondary prevention (HR: 1.08; 95% CI: 0.79 to 1.47) subjects compared with nondiabetic controls.

CONCLUSIONS

Risk of diabetes was increased after statins, but outcomes were favorable.

Complications of diagnostic electrophysiologic studies and radiofrequency catheter ablation in patients with tachyarrhythmias: an eight-year survey of 3,966 consecutive procedures in a tertiary referral center

Predictors and comparisons of complications in patients with electrophysiologic study or radiofrequency ablation have not been assessed in previous published reports. The purpose of this study was to prospectively evaluate the procedure-specific complications and investigate the possible causes and predictors of complications in electrophysiologic study and radiofrequency ablation. Data of diagnostic electrophysiologic studies and radiofrequency ablation were prospective, and represented a consecutive series of 2,593 patients with 3,966 procedures. The present study showed that a significantly higher complication rate occurred in radiofrequency ablation than in electrophysiologic study (3.1% vs. 1.1%, respectively, p = 0.00002) and a significantly higher complication rate occurred in elderly than in young patients with electrophysiologic study (2.2% vs 0.5%, p = 0.0002) or radiofrequency ablation (6.1% vs 2.0%, p = 0.00015). Multiple logistic analysis found that older age (p < 0.01) and systemic disease in elderly patients (p < 0.01) were the independent predictors of complications in both procedures. Furthermore, there was no temporal trend in the incidence of complication. We conclude that the incidence of complication was higher in radiofrequency ablation, and elderly patients had a higher incidence of complications in both electrophysiologic study and radiofrequency ablation; these procedures, when performed by experienced personnel in an appropriately staffed and equipped laboratory, can be undertaken with an acceptable risk.

Comparisons of quality of life and cardiac performance after complete atrioventricular junction ablation and atrioventricular junction modification in patients with medically refractory atrial fibrillation

OBJECTIVES

This study compared the long-term effects of complete atrioventricular junction (AVJ) ablation with those of AVJ modification in patients with medically refractory atrial fibrillation (AF).

BACKGROUND

Comparisons between the long-term effects of AVJ ablation with those of AVJ modification in patients with medically refractory AF have not been systematically studied.

METHODS

Sixty patients with medically refractory AF were randomly assigned to receive complete AVJ ablation with permanent pacing or AVJ modification. Subjective perception of quality of life (QOL) was assessed by a semiquantitative questionnaire before and 1 and 6 months after ablation. Cardiac performance was evaluated by echocardiography and radionuclide angiography within 24 h (baseline) and at 1 and 6 months after ablation.

RESULTS

Both methods were associated with significant improvement in general QOL and a significant reduction in the frequency of major symptoms and symptoms during attacks. The frequency of hospital admission and emergency room visits and antiarrhythmic drug trials significantly decreased after ablation in both groups. However, patients after complete AVJ ablation had a significantly greater improvement in general QOL and a significantly reduced frequency of major symptoms and symptoms during attacks (including palpitation, dizziness, chest oppression, blurred vision and syncope). Left ventricular (LV) systolic function and the ability to perform activities of daily life significantly improved after ablation in patients with depressed LV function in both groups. All improvements after ablation or modification were maintained over the 6-month follow-up period.

CONCLUSIONS

AVJ ablation with permanent pacing, as compared with AVJ modification, had a significantly greater ability to decrease the frequency of attacks and the extent of symptoms of AF, and the patients who received this procedure were more satisfied with their general well-being.

Hypertension and cardiac arrhythmias: a consensus document from the European Heart Rhythm Association (EHRA) and ESC Council on Hypertension, endorsed by the Heart Rhythm Society (HRS), Asia-Pacific Heart Rhythm Society (APHRS) and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE)

Hypertension is a common cardiovascular risk factor leading to heart failure (HF), coronary artery disease, stroke, peripheral artery disease and chronic renal insufficiency. Hypertensive heart disease can manifest as many cardiac arrhythmias, most commonly being atrial fibrillation (AF). Both supraventricular and ventricular arrhythmias may occur in hypertensive patients, especially in those with left ventricular hypertrophy (LVH) or HF. Also, some of the antihypertensive drugs commonly used to reduce blood pressure, such as thiazide diuretics, may result in electrolyte abnormalities (e.g. hypokalaemia, hypomagnesemia), further contributing to arrhythmias, whereas effective control of blood pressure may prevent the development of the arrhythmias such as AF. In recognizing this close relationship between hypertension and arrhythmias, the European Heart Rhythm Association (EHRA) and the European Society of Cardiology (ESC) Council on Hypertension convened a Task Force, with representation from the Heart Rhythm Society (HRS), Asia-Pacific Heart Rhythm Society (APHRS), and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE), with the remit to comprehensively review the available evidence to publish a joint consensus document on hypertension and cardiac arrhythmias, and to provide up-to-date consensus recommendations for use in clinical practice. The ultimate judgment regarding care of a particular patient must be made by the healthcare provider and the patient in light of all of the circumstances presented by that patient.