Systemic primary carnitine deficiency induces severe arrhythmia due to shortening of QT interval.

BACKGROUND: Systemic primary carnitine deficiency (PCD) is characterized by cardiomyopathy and arrhythmia. Without carnitine supplementation, progression is usually towards fatal cardiac decompensation. While the cardiomyopathy is most likely secondary to energy deficiency, the mechanism of arrhythmia is unclear, and may be related to a short QT interval. OBJECTIVE: We aim to describe rhythmic manifestations at diagnosis and with carnitine supplementation. METHODS: French patients diagnosed for PCD were retrospectively included. Clinical and para clinical data at diagnosis and during follow-up were collected. Electrocardiograms with QT interval measurements were blinded reviewed by two paediatric cardiologists. RESULTS: Nineteen patients (median age at diagnosis 2.3 years (extremes 0.3-28.9)) followed in 8 French centres were included. At diagnosis, 21% of patients (4/19) had arrhythmia (2 ventricular fibrillations, 1 ventricular tachycardia and 1 sudden death), and 84% (16/19) had cardiomyopathy. Six electrocardiograms before treatment out of 11 available displayed a short QT (QTc < 340 ms). Median corrected QTc after carnitine supplementation was 404 ms (extremes 341-447) versus 350 ms (extremes 282-421) before treatment (p < 0.001). The whole QTc was prolonged, and no patient reached the criterion of short QT syndrome with carnitine supplementation. Three patients died, probably from rhythmic cause without carnitine supplementation (two extra-hospital sudden deaths and one non-recoverable rhythmic storm before carnitine supplementation), whereas no rhythmic complication occurred in patients with carnitine supplementation. CONCLUSION: PCD is associated with shortening of the QT interval inducing severe arrhythmia. A potential explanation would be a toxic effect of accumulated fatty acid and metabolites on ionic channels embedded in the cell membrane. Carnitine supplementation normalizes the QTc and prevents arrhythmia. Newborn screening of primary carnitine deficiency would prevent avoidable deaths.

The plant-derived alkaloid aloperine prevents ischemia/reperfusion injury-induced sudden cardiac death.

Sudden cardiac death (SCD) remains a major cause of global mortality. In addition to modern interventions, botanical folk medicines have long been used to treat cardiovascular disease, although the efficacy and underlying mechanisms are often unresolved. Aloperine, a bioactive quinolizidine alkaloid isolated from Sophora alopecuroides plants, exhibits antioxidant, anti-inflammatory, antitumor, and vasorelaxant properties, but possible antiarrhythmic effects of aloperine in SCD are unclear. Here, we examined whether aloperine protects against ischemia and reperfusion injury-associated lethal ventricular arrhythmia and sudden cardiac death. Rats were divided into sham, control, and aloperine groups, and reperfusion-provoked ventricular arrhythmogenesis, cardiac damage markers, and signaling pathways quantified following left main coronary artery ischemia and reperfusion. In vitro studies of effects of aloperine on hERG and Kv4.3 cardiac voltage-gated potassium (Kv) channels were performed using two-electrode voltage clamp analysis of cloned channels expressed in Xenopus laevis oocytes. Aloperine pretreatment (10 mg/kg) did not affect baseline cardiac electrical stability; yet, it reduced ventricular arrhythmogenesis and susceptibility to SCD (mortality rate: control: 64.3%; aloperine: 0%) induced by reperfusion injury. Aloperine also reduced serum levels of LDH, CK-MB, α-HBDH, and cTnI post-I/R, and stimulated phosphorylation of ventricular ERK1/2 and STAT-3, which are key components of RISK and SAFE signaling pathways. Inhibition of either ERK1/2 (with U0126) or STAT-3 (with Ag490) abolished aloperine-induced anti-arrhythmic effects and ERK1/2 and STAT-3 phosphorylation. Interestingly, while aloperine (100 µM) had no effect on cloned Kv4.3 activity, aloperine (1 µM and up) negative-shifted the voltage dependence of hERG activation by ~10 mV and increased peak hERG current by 35%. Thus, aloperine exerts striking anti-arrhythmic effects against myocardial ischemia and reperfusion injury-induced severe lethal ventricular arrhythmia and sudden cardiac death via the ERK1/2/STAT-3 signaling pathway, with potential additional contribution from increased cardiac myocyte repolarization capacity via augmented hERG activity.

Evaluation of the effect of sodium zirconium cyclosilicate on arrhythmia-related cardiovascular outcomes in patients receiving chronic haemodialysis with hyperkalaemia: protocol for the multicentre, randomised, controlled DIALIZE-Outcomes study.

INTRODUCTION: Patients with kidney failure receiving chronic haemodialysis have elevated risk of arrhythmias potentially increasing the likelihood of sudden cardiac death, stroke and hospitalisation. The DIALIZE study (NCT03303521) demonstrated that sodium zirconium cyclosilicate (SZC) was an efficacious and well-tolerated treatment for predialysis hyperkalaemia in patients undergoing haemodialysis. The DIALIZE-Outcomes study evaluates the effect of SZC on sudden cardiac death and arrhythmia-related cardiovascular outcomes in patients receiving chronic haemodialysis with recurrent hyperkalaemia. METHODS AND ANALYSIS: International, multicentre, randomised, double-blind, placebo-controlled study conducted at 357 study sites across 25 countries. Adults (≥18 years) receiving chronic haemodialysis three times per week with recurrent predialysis serum potassium (K+) ≥5.5 mmol/L post long interdialytic interval (LIDI) are eligible. Patients (~2800) will be randomised 1:1 to SZC or placebo, starting at 5 g orally once daily on non-dialysis days and titrated weekly in 5 g increments (maximum 15 g) to target predialysis serum K+ 4.0-5.0 mmol/L post LIDI. The primary objective is to evaluate efficacy of SZC versus placebo in reducing occurrence of the primary composite endpoint of sudden cardiac death, stroke or arrhythmia-related hospitalisation, intervention or emergency department visit. Secondary endpoints include efficacy of SZC versus placebo in maintaining normokalaemia (serum K+ 4.0-5.5 mmol/L post LIDI) at the 12-month visit, preventing severe hyperkalaemia (serum K+ ≥6.5 mmol/L post LIDI) at the 12-month visit and reducing the incidence of individual cardiovascular outcomes. Safety of SZC will be evaluated. The study is event driven, with participants remaining in the study until 770 primary endpoint events have occurred. Average time in the study is expected to be ~25 months. ETHICS AND DISSEMINATION: Approval was obtained from the relevant institutional review board/independent ethics committee from each participating site (approving bodies in supplementary information). The results will be submitted to a peer-reviewed journal. TRIAL REGISTRATION NUMBERS: EudraCT 2020-005561-14 and clinicaltrials.gov identifier NCT04847232.

Right ventricular epicardial arrhythmogenic substrate in long-QT syndrome patients at risk of sudden death.

AIMS: The long-QT syndrome (LQTS) represents a leading cause of sudden cardiac death (SCD). The aim of this study was to assess the presence of an underlying electroanatomical arrhythmogenic substrate in high-risk LQTS patients. METHODS AND RESULTS: The present study enrolled 11 consecutive LQTS patients who had experienced frequent implantable cardioverter-defibrillator (ICD discharges triggered by ventricular fibrillation (VF). We acquired electroanatomical biventricular maps of both endo and epicardial regions for all patients and analyzed electrograms sampled from several myocardial regions. Abnormal electrical activities were targeted and eliminated by the means of radiofrequency catheter ablation. VF episodes caused a median of four ICD discharges in eleven patients (6 male, 54.5%; mean age 44.0 ± 7.8 years, range 22-53) prior to our mapping and ablation procedures. The average QTc interval was 500.0 ± 30.2 ms. Endo-epicardial biventricular maps displayed abnormally fragmented, low-voltage (0.9 ± 0.2 mV) and prolonged electrograms (89.9 ± 24.1 ms) exclusively localized in the right ventricular epicardium. We found electrical abnormalities extending over a mean epicardial area of 15.7 ± 3.1 cm2. Catheter ablation of the abnormal epicardial area completely suppressed malignant arrhythmias over a mean 12 months of follow-up (median VF episodes before vs. after ablation, 4 vs. 0; P = 0.003). After the procedure, the QTc interval measured in a 12-lead ECG analysis shortened to a mean of 461.8 ± 23.6 ms (P = 0.004). CONCLUSION: This study reveals that, among high-risk LQTS patients, regions localized in the epicardium of the right ventricle harbour structural electrophysiological abnormalities. Elimination of these abnormal electrical activities successfully prevented malignant ventricular arrhythmia recurrences.

A survey study of the use of a subcutaneous implantable cardioverter-defibrillator in various clinical scenarios by expert electrophysiologists in Poland.

BACKGROUND: A subcutaneous implantable cardioverter-defibrillator (S-ICD) has become a recognized alternative to a traditional transvenous implantable cardioverter-defibrillator (T-ICD). Despite the growing evidence of non-inferiority of S-ICD, there are no clear clinical guidelines for selection of either of the two available systems. The aim of the study was to analyze the decisions made in predefined typical clinical scenarios by Polish cardiologists experienced in the use of both S-ICDs and T-ICDs. METHODS: A group of 30 experts of cardiac electrotherapy experienced in the use of S-ICDs was recruited and invited to participate in a web-based anonymous survey. The survey questions regarded the proposed therapy in various but typical clinical scenarios. RESULTS: From the invited 30 experts representing 18 clinical centers, 25 completed the survey. 72% of them declared that the number of S-ICDs implanted at their center during the preceding 12 months exceeded 10, and 40% - that it was over 20. Rates of responders preferring S-ICD or T-ICD in various clinical scenarios are reported and discussed in detail. CONCLUSIONS: Significant divergence of opinion exists among Polish experts regarding the use of a subcutaneous cardioverter-defibrillator. It is especially pronounced on the issue of the use of the system in middle-age patients, in case of complications of the hitherto ICD therapy, or the need of upgrading the existing cardiac implantable electronic device.

Myocardial ATP depletion detected noninvasively predicts sudden cardiac death risk in patients with heart failure.

BACKGROUNDSudden cardiac death (SCD) remains a worldwide public health problem in need of better noninvasive predictive tools. Current guidelines for primary preventive SCD therapies, such as implantable cardioverter defibrillators (ICDs), are based on left ventricular ejection fraction (LVEF), but these guidelines are imprecise: fewer than 5% of ICDs deliver lifesaving therapy per year. Impaired cardiac metabolism and ATP depletion cause arrhythmias in experimental models, but to our knowledge a link between arrhythmias and cardiac energetic abnormalities in people has not been explored, nor has the potential for metabolically predicting clinical SCD risk.METHODSWe prospectively measured myocardial energy metabolism noninvasively with phosphorus magnetic resonance spectroscopy in patients with no history of significant arrhythmias prior to scheduled ICD implantation for primary prevention in the setting of reduced LVEF (≤35%).RESULTSBy 2 different analyses, low myocardial ATP significantly predicted the composite of subsequent appropriate ICD firings for life-threatening arrhythmias and cardiac death over approximately 10 years. Life-threatening arrhythmia risk was approximately 3-fold higher in patients with low ATP and independent of established risk factors, including LVEF. In patients with normal ATP, rates of appropriate ICD firings were several-fold lower than reported rates of ICD complications and inappropriate firings.CONCLUSIONTo the best of our knowledge, these are the first data linking in vivo myocardial ATP depletion and subsequent significant arrhythmic events in people, suggesting an energetic component to clinical life-threatening ventricular arrhythmogenesis. The findings support investigation of metabolic strategies that limit ATP loss to treat or prevent life-threatening cardiac arrhythmias and herald noninvasive metabolic imaging as a complementary SCD risk stratification tool.TRIAL REGISTRATIONClinicalTrials.gov NCT00181233.FUNDINGThis work was supported by the DW Reynolds Foundation, the NIH (grants HL61912, HL056882, HL103812, HL132181, HL140034), and Russell H. Morgan and Clarence Doodeman endowments at Johns Hopkins.

A Multicenter External Validation of a Score Model to Predict Risk of Events in Patients With Brugada Syndrome.

A multivariate risk score model was proposed by Sieira et al in 2017 for sudden death in Brugada syndrome; their validation in 150 patients was highly encouraging, with a C-index of 0.81; however, this score is yet to be validated by an independent group. A total of 192 records of patients with Brugada syndrome were collected from 2 centers in the United Kingdom and retrospectively scored according to a score model by Sieira et al. Data were compiled summatively over follow-up to mimic regular risk re-evaluation as per current guidelines. Sudden cardiac death survivor data were considered perievent to ascertain the utility of the score before cardiac arrest. Scores were compared with actual outcomes. Sensitivity in our cohort was 22.7%, specificity was 57.6%, and C-index was 0.58. In conclusion, up to 75% of cardiac arrest survivors in this cohort would not have been offered a defibrillator if evaluated before their event. This casts doubt on the utility of the score model for primary prevention of sudden death. Inherent issues with modern risk scoring strategies decrease the likelihood of success even in robustly designed tools such as the Sieira score model.

Impact of Dietary Factors on Brugada Syndrome and Long QT Syndrome.

A healthy regime is fundamental for the prevention of cardiovascular diseases (CVD). In inherited channelopathies, such as Brugada syndrome (BrS) and Long QT syndrome (LQTS), unfortunately, sudden cardiac death could be the first sign for patients affected by these syndromes. Several known factors are used to stratify the risk of developing cardiac arrhythmias, although none are determinative. The risk factors can be affected by adjusting lifestyle habits, such as a particular diet, impacting the risk of arrhythmogenic events and mortality. To date, the importance of understanding the relationship between diet and inherited channelopathies has been underrated. Therefore, we describe herein the effects of dietary factors on the development of arrhythmia in patients affected by BrS and LQTS. Modifying the diet might not be enough to fully prevent arrhythmias, but it can help lower the risk.

Plasma Omega-3 Fatty Acids and the Risk of Cardiovascular Events in Patients After an Acute Coronary Syndrome in MERLIN-TIMI 36.

Background Plasma omega-3 polyunsaturated fatty acids (ω3-PUFAs) have been shown to be inversely correlated with the risk of cardiovascular death in primary prevention. The risk relationship in the setting of an acute coronary syndrome is less well established. Methods and Results Baseline plasma ω3-PUFA composition (α-linolenic acid, eicosapentaenoic acid, docosapentaenoic acid, and docosahexaenoic acid) was assessed through gas chromatography with flame ionization detection in a case-cohort study involving 203 patients with cardiovascular death, 325 with myocardial infarction, 271 with ventricular tachycardia, and 161 with atrial fibrillation, and a random sample of 1612 event-free subjects as controls from MERLIN-TIMI 36 (Metabolic Efficiency With Ranolazine for Less Ischemia in Non-ST-Elevation-Acute Coronary Syndrome-Thrombolysis in Myocardial Infarction 36), a trial of patients hospitalized with non-ST-segment-elevation -acute coronary syndrome. After inverse-probability-weighted multivariable adjustment including all traditional risk factors, a higher relative proportion of long-chain ω3-PUFAs (eicosapentaenoic acid, docosapentaenoic acid, docosahexaenoic acid) were associated with 18% lower odds of cardiovascular death (adjusted [adj] odds ratio [OR] per 1 SD, 0.82; 95% CI, 0.68-0.98) that was primarily driven by 27% lower odds of sudden cardiac death (adj OR per 1 SD, 0.73; 95% CI, 0.55-0.97). Long-chain ω3-PUFA levels in the top quartile were associated with 51% lower odds of cardiovascular death (adj OR 0.49; 95% CI, 0.27-0.86) and 63% lower odds of sudden cardiac death (adj OR, 0.37; 95% CI, 0.16-0.56). An attenuated relationship was seen for α-linolenic acid and subsequent odds of cardiovascular (adj OR, 0.92; 95% CI, 0.74-1.14) and sudden cardiac death (adj OR, 0.91; 95% CI, 0.67-1.25). No significant relationship was observed between any ω3-PUFAs and the odds of cardiovascular death unrelated to sudden cardiac death, myocardial infarction, atrial fibrillation, or early post-acute coronary syndrome ventricular tachycardia. Conclusions In patients after non-ST-segment-elevation-acute coronary syndrome, plasma long-chain ω3-PUFAs are inversely associated with lower odds of sudden cardiac death, independent of traditional risk factors and lipids. Registration URL: https://www.clinicaltrials.gov. Unique identifier: NCT00099788.

Tumescent local anesthesia versus general anesthesia for subcutaneous implantable cardioverter-defibrillator implantation.

BACKGROUND: Subcutaneous implantable cardioverter-defibrillator (S-ICD) is an effective alternative to transvenous implantable cardioverter-defibrillator. General anesthesia (GA) is considered the standard sedation approach because of the pain caused by the manipulation of subcutaneous tissue with S-ICD implantation. However, GA carries several limitations, including additional risk of adverse events, prolonged in-room times, and increased costs. OBJECTIVE: The purpose of this study was to define the effectiveness and safety of tumescent local anesthesia (TLA) in comparison to GA in patients undergoing S-ICD implantation. METHODS: We performed a prospective, nonrandomized, controlled, multicenter study of patients referred for S-ICD implantation between 2019 and 2020. Patients were allocated to either TLA or GA on the basis of patient's preferences and/or anesthesia service availability. TLA was prepared using lidocaine, epinephrine, sodium bicarbonate, and sodium chloride. All patients provided written informed consent, and the institutional review board at each site provided approval for the study. RESULTS: Sixty patients underwent successful S-ICD implantation from July 2019 to November 2020. Thirty patients (50%) received TLA, and the rest GA. There were no differences between groups with regard to baseline characteristics. In-room and procedural times were significantly shorter with TLA (107.6 minutes vs 186 minutes; P < .0001 and 53.2 minutes vs 153.7 minutes; P < .0001, respectively). Pain was reported less frequently by patients who received TLA. The use of opioids was significantly reduced in patients who received TLA (23% vs 62%; P = .002). CONCLUSION: TLA is an effective and safe alternative to GA in S-ICD implantation. The use of TLA is associated with shorter in-room and procedural times, less postprocedural pain, and reduced usage of opioids and acetaminophen for analgesia.

Omega-3 polyunsaturated fatty acid supplementation improves lipid metabolism and endothelial function by providing a beneficial eicosanoid-pattern in patients with acute myocardial infarction: A randomized, controlled trial.

BACKGROUND & AIMS: Omega-3 polyunsaturated fatty acid (ω-3 PUFA) have been reported to have beneficial cardiovascular effects, but its mechanism of protection against acute myocardial infarction (AMI) who are under guideline-based therapy is not fully understood. Here, we used a metabolomic approach to systematically analyze the eicosanoid metabolites induced by ω-3 PUFA supplementation and investigated the underlying mechanisms. METHODS: Participants with AMI after successful percutaneous coronary intervention were randomized to 3 months of 2 g daily ω-3 PUFA and guideline-adjusted therapy (n = 30, ω-3 therapy) or guideline-adjusted therapy alone (n = 30, Usual therapy). Functional PUFA-derived eicosanoids in plasma were profiled by metabolomics. Clinical and laboratory tests were obtained before and 3 months after baseline and after the study therapy. RESULTS: By intent-to-treat analysis, the content of 11-HDoHE, 20-HDoHE and 16,17-EDP and that of epoxyeicosatetraenoic acids (EEQs), derived from docosahexaenoic acid and eicosapentaenoic acid, respectively, were significantly higher with ω-3 group than Usual therapy, whereas that of prostaglandin J2 (PGJ2) and leukotriene B4, derived from arachidonic acid, was significantly decreased. As compared with Usual therapy, ω-3 PUFA therapy significantly reduced levels of triglycerides (-6.3%, P < 0.05), apolipoprotein B (-4.9%, P < 0.05) and lipoprotein(a) (-37.0%, P < 0.05) and increased nitric oxide level (62.2%, P < 0.05). In addition, the levels of these variables were positively correlated with change in 16,17-EDP and EEQs content but negatively with change in PGJ2 content. CONCLUSIONS: ω-3 PUFA supplementation may improve lipid metabolism and endothelial function possibly by affecting eicosanoid metabolic status at a systemic level during convalescent healing after AMI. CLINICAL TRIAL REGISTRATION: URL: http://www.chictr.org.cn. Unique identifier: ChiCTR1900025859.

[Influence of Omega-3 PUFA on Non-invasive factors determining the risk of arrhYthmias eXcess and sudden cardiac death in patients with HFpEF with ischemic etiology (ONYX)].

Aim Patients with heart failure with reduced left ventricular (LV) ejection fraction (HFrEF) who have had acute myocardial infarction have an unfavorable prognosis, largely due to ventricular arrhythmias (VA) and risk of sudden cardiac death (SCD). The optimal treatment (triple neurohormonal blockade plus implantable cardioverter defibrillator and cardiac resynchronization therapy) reduced the risk of SCD primarily due to reverse cardiac remodeling, but has not solved this problem completely. Efficacy of purified ω-3 polyunsaturated fatty acid esters (PUFA) in low doses (1 g/day) in reducing VA and risk of SCD in HFrEF patients was demonstrated in two large randomized clinical trials. The PUFA effects was suggested to be related also with increased heart rhythm variability (HRV) and chronotropic action, which might depend on the drug dose. The present open, prospective, randomized, comparative study in parallel groups evaluated the effect of Omacor in different doses on noninvasive markers of SCD risk in patients with ischemic HFrEF receiving the optimal drug therapy.Methods Patients (n=40) were randomized at a 1:1:2 ratio to the control group (n=10), the Omacor 1 g/day treatment group (n=10), and the Omacor 2 g/day treatment group (n=20) and were followed up for 12 months. Clinical evaluation included changes in the CHF functional class (FC) and Clinical Condition Scale (CCS) score; concentration of N-terminal pro-hormone brain natriuretic peptide (NT-proBNP); and peak oxygen consumption during exercise (peak VO2). The LV function was evaluated by LVEF. Holter ECG monitoring was used for evaluation of HRV (SDNN), average 24-h heart rate (HR), number of ventricular extrasystoles (VE) per hour and severity of VA, and presence of paired VE and VT runs.Results Improvement of CHF FC became significant only with the high-dose Omacor treatment (2 g/day). The CCS score showed a tendency towards decrease also with a lower dose (1 g/day) whereas the level of NT-proBNP significantly decreased with both Omacor doses. The increase in LV EF was significant only with the use of Omacor 2 g/day (+3 %, р=0.002). A negative chronotropic effect of ω-3 PUFA was observed. Average 24-h HR decreased by 8 bpm (р=0.05) and 11 bpm (р<0.001) with Omacor 1 g/day and 2 g/day, respectively. Either dose of ω-3 PUFA significantly improved VO2, which directly correlated with LV EF and inversely correlated with HR. The decrease in number of VE was associated not only with improved HRV (SDNN) but also with the decrease in 24-h HR, and thus Omacor 2 g/day significantly decreased the number of VE (by 16 per hour) and dangerous VA (paired VE and VT runs ceased to be detected in 40 % of patients).Conclusion Since HR, HRV, and VA are closely interrelated, the effect of ω-3 PUFA specifically on these noninvasive markers apparently determines its ability to decrease the risk of SCD in patients with ischemic HFrEF. The antiarrhythmic effect of Omacor was greater with higher doses of this drug.

Myotonic dystrophy type 1 and high ventricular vulnerability at the electrophysiological evaluation: ICD yes or not?

A significant number of sudden death (SD) is observed in myotonic dystrophy (DM1) despite pacemaker implantation and some consider the ICD to be the preferential device in patients with conduction disease. According to the latest guidelines, prophylactic ICD implantation in patients with neuromuscular disorder should follow the same recommendations of non-ischemic dilated cardiomyopathy, being reasonable when pacing is needed. We here report a case of DM1 patient who underwent ICD implantation even in the absence of conduction disturbances on ECG and ventricular dysfunction/fibrosis at cardiac magnetic resonance. The occurrence of syncope, non-sustained ventricular tachycardias at 24-Holter ECG monitoring and a family history of SD resulted associated with ventricular fibrillation inducibility at electrophysiological study, favouring ICD implantation. On our advice, DM1 patient with this association of SD risk factors should be targeted for ICD implantation.

Impact of Different Doses of Omega-3 Fatty Acids on Cardiovascular Outcomes: a Pairwise and Network Meta-analysis.

PURPOSE OF REVIEW: Omega-3 fatty acid (O3FA) supplementation has shown conflicting evidence regarding its benefit in cardiovascular events. We performed a pairwise and network meta-analysis to elucidate the benefit of different doses of O3FA supplementation in cardiovascular prevention. RECENT FINDINGS: Fourteen studies were identified providing data on 125,763 patients. A prespecified cut-off value of < 1 g per day was set for low-dose (LD) O3FA and > 1 g per day for high-dose (HD) O3FA. The efficacy outcomes of interest were total death, cardiac death, sudden cardiac death, myocardial infarction, stroke, coronary revascularization, unstable angina, and major vascular events. Safety outcomes of interest were bleeding, gastrointestinal disturbances, and atrial fibrillation events. HD treatment was associated with a lower risk of cardiac death (IRR 0.79, 95% CI [0.65-0.96], p = 0.03 versus control), myocardial infarction (0.71 [0.62-0.82], p < 0.0001 versus control and 0.79 [0.67-0.92], p = 0.003 versus LD), coronary revascularization (0.74 [0.66-0.83], p < 0.0001 versus control and 0.74 [0.66-0.84], p < 0.0001 versus LD), unstable angina (0.73 [0.62-0.86], p = 0.0001 versus control and 0.74 [0.62-0.89], p = 0.002 versus LD), and major vascular events (0.78 [0.71-0.85], p < 0.0001 versus control and 0.79 [0.72-0.88], p < 0.0001 versus LD). HD treatment was associated with increased risk for bleeding events (1.49 [1.2-1.84], p = 0.0002 versus control and 1.63 [1.16-2.3], p = 0.005 versus LD) and increased atrial fibrillation events compared to control (1.35 [1.1-1.66], p = 0.004). HD O3FA treatment was associated with lower cardiovascular events compared to LD and to control, but increased risk for bleeding and atrial fibrillation events.

2020 Canadian Cardiovascular Society/Canadian Heart Rhythm Society Position Statement on the Management of Ventricular Tachycardia and Fibrillation in Patients With Structural Heart Disease.

This Canadian Cardiovascular Society position statement is focused on the management of sustained ventricular tachycardia (VT) and ventricular fibrillation (VF) that occurs in patients with structural heart disease (SHD), including previous myocardial infarction, dilated cardiomyopathy, and other forms of nonischemic cardiomyopathy. This patient population is rapidly increasing because of advances in care and improved overall survival of patients with all forms of SHD. In this position statement, the acute and long-term management of VT/VF are outlined, and the many unique aspects of care in this population are emphasized. The initial evaluation, acute therapy, indications for chronic suppressive therapy, choices of chronic suppressive therapy, implantable cardioverter-defibrillator programming, alternative therapies, and psychosocial care are reviewed and recommendations for optimal care are provided. The target audience for this statement includes all health professionals involved in the continuum of care of patients with SHD and VT/VF.

Preparticipation Cardiovascular Screening: An Infrastructure Assessment in Collegiate Athletics.

OBJECTIVE: To assess the available infrastructure for secondary testing after preparticipation cardiovascular screening of collegiate athletes. DESIGN: Cross-sectional study. SETTING: National Collegiate Athletic Association (NCAA) athletic programs PARTICIPANTS:: Team physicians. INTERVENTIONS: Online survey distributed by the NCAA and American Medical Society for Sports Medicine. MAIN OUTCOME MEASURES: Availability of secondary cardiovascular diagnostic testing and services. RESULTS: Team physicians from 235 schools completed the assessment, representing 21% of all NCAA schools. Ninety (38.3%) NCAA team physicians reported screening athletes using electrocardiogram (ECG). Division I schools were more likely than Division II and III schools to perform both screening ECG (RR, 2.38, P < 0.0001) and echocardiogram (RR, 2.83, P = 0.01). More than 97% of schools had access to resting echocardiogram, stress ECG/echocardiogram, and Holter monitoring within 25 miles with no significant variability between divisions, regions, or size of undergraduate student body. Cardiac magnetic resonance imaging and electrophysiology studies were available within 25 miles of more than 80% of schools, and genetics testing was available within 25 miles for 64.8%. CONCLUSIONS: Secondary testing for cardiovascular abnormalities seems to be readily available for NCAA athletes, regardless of division, region, or school size.

The Effect of Marine n-3 Polyunsaturated Fatty Acids on Heart Rate Variability in Renal Transplant Recipients: A Randomized Controlled Trial.

Resting heart rate (rHR) and heart rate variability (HRV) are non-invasive measurements that predict the risk of sudden cardiac death (SCD). Marine n-3 polyunsaturated fatty acid (PUFA) supplementation may decrease rHR, increase HRV, and reduce the risk of SCD. To date, no studies have investigated the effect of marine n-3 PUFA on HRV in renal transplant recipients. In a randomized controlled trial, 132 renal transplant recipients were randomized to receive either three 1 g capsules of marine n-3 PUFA, each containing 460 mg/g EPA and 380 mg/g DHA, or control (olive oil) for 44 weeks. HRV was calculated in the time and frequency domains during a conventional cardiovascular reflex test (response to standing, deep breathing, and Valsalva maneuver) and during 2 min of resting in the supine position. There was no significant effect of marine n-3 PUFA supplementation on time-domain HRV compared with controls. rHR decreased 3.1 bpm (± 13.1) for patients receiving marine n-3 PUFA compared to 0.8 (± 11.0) in controls (p = 0.28). In the frequency domain HRV analyses, there was a significant change in response to standing in both high and low frequency measures, 2.9 (p = 0.04, 95% CI (1.1;8)) and 2.7 (p = 0.04, 95% CI (1.1;6.5)), respectively. In conclusion, 44 weeks of supplemental marine n-3 PUFAs in renal transplant recipients significantly improved the cardiac autonomic function, assessed by measuring HRV during conventional cardiovascular reflex tests.