Heart failure and atrial fibrillation: new concepts in pathophysiology, management, and future directions.

A bidirectional pathophysiological link connects heart failure and atrial fibrillation, creating a frequent and challenging comorbidity, which includes neurohormonal hyperactivation, fibrosis development, and electrophysiologic remodeling, while they share mutual risk factors. Management for these devastating comorbidities includes most of the established treatment measures for heart failure as well as rhythm or rate control and anticoagulation mostly for atrial fibrillation, which can be achieved with either pharmaceutical or non-pharmaceutical approaches. The current manuscript aims to review the existing literature regarding the underlying pathophysiology, to present the novel trends of treatment, and to predict the future perspective of these two linked diseases with the numerous unanswered questions.

Increasing age does not affect time to appropriate therapy in primary prevention ICD/CRT-D: a competing risks analysis.

Aims: To evaluate the impact of age on the clinical outcomes in a primary prevention implantable cardioverter defibrillator (ICD)/cardiac resynchronization therapy defibrillator (CRT-D) population. Methods and Results: A retrospective, multicentre analysis of patients aged 60 years and over with primary prevention ICD/CRT-D devices implanted between 1 January 2006 and 1 November 2014 was performed. Survival to follow-up with no therapy (T1), death prior to follow-up with no therapy (T2), delivery of appropriate therapy with survival to follow-up (T3), and delivery of appropriate therapy with death prior to follow-up (T4) were measured. In total, 424 patients were eligible for inclusion in the analysis, mean follow-up of 32.6 months during which time 44 patients (10.1%) received appropriate therapy. The sub-hazard ratio (SHR) for the cumulative incidence of appropriate therapy (T3) according to age at implant was 1.00 (P = 0.851; 95% CI 0.96­1.04). The SHR for cumulative incidence of death (T2) according to age at implant was 1.06 (P < 0.001; 95% CI 1.03­1.01). Age at implant, ischaemic aetiology, baseline haemoglobin, and the presence of diabetes mellitus were predictors of all-cause mortality. Conclusion: Age has no impact on the time to appropriate therapy, but risk of death prior to therapy increases by 6% for every year increment. As the ICD population ages, the proportion who die without receiving appropriate therapy increases due to competing risks. Characterizing competing risks predictive of death independent of ICD indication would focus therapy on those with potential to benefit and reduce unnecessary exposure to ICD-related morbidity.

Left bundle branch area pacing versus conventional pacing in patients with advanced atrioventricular conduction abnormalities: a prospective cohort study.

BACKGROUND: Left bundle branch area pacing (LBBAP) is an emerging pacing method that may prevent the deleterious effects of right ventricular pacing. The aim of this study is to compare the effects of LBBAP with right ventricular septal pacing (RVSP) in patients with advanced atrioventricular conduction abnormalities and preserved left ventricular ejection fraction. METHODS: The effect of pacing was evaluated by echocardiographic indices of dyssynchrony, including global myocardial work efficiency (GWE) and peak systolic dispersion (PSD). The primary endpoint was GWE postprocedural, at 3, 6, and 12 months after the procedure. RESULTS: Twenty patients received LBBAP and 18 RVSP. Complete follow-up was accomplished in 37 patients (97.4%) due to the death of a patient (RVSP arm) from nonrelated cause. GWE was significantly increased in the group of LBBAP compared to RVSP at all time points (90.8% in LBBAP versus 85.8% in RVSP group at 12 months, p = 0.01). PSD was numerically lower in the LBBAP arm at all time points, yet not statistically significant (56.4 msec in LBBP versus 65.1 msec in RVSP arm at 12 months, p = 0.178). The implantation time was increased (median 93 min in LBBAP versus 45 min in RVSP group, p < 0.01), along with fluoroscopy time and dose area product (DAP), in the arm of LBBAP. There were no severe perioperative acute complications in either group. CONCLUSIONS: LBBAP is an emerging and safe technique for patients with a pacing indication. Despite the longer procedural and fluoroscopy time, as well as higher DAP, LBBAP seems to offer better left ventricular synchrony compared to RVSP, according to GWE measurements.

Efficacy and Safety of Thirty-Day Dual-Antiplatelet Therapy Following Complex Percutaneous Coronary Intervention: A Systematic Review and Meta-Analysis.

The optimal duration of DAPT after complex PCI remains under investigation. The purpose of this systematic review and meta-analysis was to explore the safety and efficacy of a one-month therapy period versus a longer duration of DAPT after complex PCI. We systematically screened three major databases, searching for randomized controlled trials or sub-analyses of them, which compared shortened DAPT (S-DAPT), namely, one month, and longer DAPT (L-DAPT), namely, more than three months. The primary endpoint was any Net Adverse Clinical Event (NACE), and the secondary was any MACE (Major Adverse Cardiac Event), its components (mortality, myocardial infarction, stroke, and stent thrombosis), and major bleeding events. Three studies were included in the analysis, with a total of 6275 patients. Shortening DAPT to 30 days after complex PCI did not increase the risk of NACEs (OR: 0.77, 95% CI: 0.52-1.14), MACEs, mortality, myocardial infractions, stroke, or stent thrombosis. Pooled major bleeding incidence was reduced, but this finding was not statistically significant. This systematic review and meta-analysis showed that one-month DAPT did not differ compared to a longer duration of DAPT after complex PCI in terms of safety and efficacy endpoints. Further studies are still required to confirm these findings.

Spontaneous Coronary Artery Dissection and COVID-19: A Review of the Literature.

SARS-CoV-2 is responsible for the global coronavirus disease 2019 (COVID-19) pandemic. While the cardiovascular effects of COVID-19 have been thoroughly described, there are limited published studies in the literature establishing a connection between spontaneous coronary artery dissection (SCAD) and COVID-19. Cardiovascular manifestations include, among others, myocarditis, acute myocardial infraction, and thrombosis. In general, SCAD is an uncommon and underdiagnosed cause of acute myocardial infarction (AMI), particularly in younger women and in patients with underlying fibromuscular dysplasia (FMD). Many patients with SCAD often report significant emotional stress, especially in relation with job loss, during the week preceding their cardiac event. Moreover, the COVID-19 pandemic has led to societal stress and increased unemployment, factors that have been associated with cardiovascular morbidity. SCAD emerges as a rare manifestation of coronary artery disease, which a few recent case reports link to COVID-19. The aim of this article is to summarize the relevant data on the pathophysiology of COVID-19 and SCAD along with a review of the reported cases on acute coronary syndrome (ACS) following SARS-CoV2 infection and, thus, to provide insights about the relationship between COVID-19 and SCAD.

Safety and efficacy of left bundle branch area pacing compared with right ventricular pacing in patients with bradyarrhythmia and conduction system disorders: Systematic review and meta-analysis.

BACKGROUND: Right Ventricular Pacing (RVP) may have detrimental effects in ventricular function. Left Bundle Branch Area Pacing (LBBAP) is a new pacing strategy that appears to have better results. The aim of this systematic review and meta-analysis is to compare the safety and efficacy of LBBAP vs RVP in patients with bradyarrhythmia and conduction system disorders. METHODS: MEDLINE, EMBASE and Pubmed databases were searched for studies comparing LBBAP with RVP. Outcomes were all-cause mortality, atrial fibrillation (AF) occurrence, heart failure hospitalizations (HFH) and complications. QRS duration, mechanical synchrony and LVEF changes were also assessed. Pairwise meta-analysis was conducted using random and fixed effects models. RESULTS: Twenty-five trials with 4250 patients (2127 LBBAP) were included in the analysis. LBBAP was associated with lower risk for HFH (RR:0.33, CI 95%:0.21 to 0.50; p < 0.001), all-cause mortality (RR:0.52 CI 95%:0.34 to 0.80; p = 0.003), and AF occurrence (RR:0.43 CI 95%:0.27 to 0.68; p < 0.001) than RVP. Lead related complications were not different between the two groups (p = 0.780). QRSd was shorter in the LBBAP group at follow-up (WMD: -32.20 msec, CI 95%: -40.70 to -23.71; p < 0.001) and LBBAP achieved better intraventricular mechanical synchrony than RVP (SMD: -1.77, CI 95%: -2.45 to -1.09; p < 0.001). LBBAP had similar pacing thresholds (p = 0.860) and higher R wave amplitudes (p = 0.009) than RVP. CONCLUSIONS: LBBAP has better clinical outcomes, preserves ventricular electrical and mechanical synchrony and has excellent pacing parameters, with no difference in complications compared to RVP.

Mechanisms of Atrial Fibrillation: How Our Knowledge Affects Clinical Practice.

Atrial fibrillation (AF) is a very common arrhythmia that mainly affects older individuals. The mechanism of atrial fibrillation is complex and is related to the pathogenesis of trigger activation and the perpetuation of arrhythmia. The pulmonary veins in the left atrium arei confirm that onfirm the most common triggers due to their distinct anatomical and electrophysiological properties. As a result, their electrical isolation by ablation is the cornerstone of invasive AF treatment. Multiple factors and comorbidities affect the atrial tissue and lead to myocardial stretch. Several neurohormonal and structural changes occur, leading to inflammation and oxidative stress and, consequently, a fibrotic substrate created by myofibroblasts, which encourages AF perpetuation. Several mechanisms are implemented into daily clinical practice in both interventions in and the medical treatment of atrial fibrillation.

Paradoxical pacing spikes during a wide complex tachycardia in biventricular defibrillator. What is the mechanism? Is it undersensing due to troubleshooting?

We present the case of a 68-year-old man with a cardiac resynchronization therapy-defibrillator Medtronic device implanted 3 years ago, admitted to our hospital due to a wide complex tachycardia with unexpected pacing spikes inside QRS complexes. Although that could be easily attributed to ventricular undersensing, more complicated mechanisms are involved, including the origin of the tachycardia, the parameters of the device, and the position of the device and the leads.

You cannot ablate the Lernaean Hydra: SCN5A mutation in a patient with multifocal ectopic Purkinje-related premature contractions syndrome treated with Flecainide and an implant of a subcutaneous defibrillator-a case report.

BACKGROUND: SCN5A mutations may present with different clinical phenotypes such as Brugada syndrome, long QT3 syndrome, sick sinus syndrome, atrial fibrillation, dilated cardiomyopathy, and the least known multifocal ectopic Purkinje-related premature contractions syndrome. CASE SUMMARY: We report a case of a 29-year-old woman with palpitations due to multifocal premature ventricular complexes (PVCs) and a family history of sudden death. The previous electrophysiological study had shown that PVCs arose from Purkinje fibres but catheter ablation was unsuccessful. Cardiac magnetic resonance (CMR) imaging demonstrated non-ischaemic areas of subendocardial fibrosis at multiple left ventricular (LV) segments with concomitant dilatation and mild systolic impairment. Amiodarone suppressed the ectopy but caused hyperthyroidism. Due to recent pregnancy, she received no antiarrhythmics which resulted in PVC burden increase and further deterioration of the ejection fraction (EF). After gestation, amiodarone was reinitiated and switched to flecainide after implantation of a subcutaneous defibrillator as a safety net. At follow-up, LV function had almost normalized. Genetic analysis confirmed an SCN5A mutation. DISCUSSION: Multifocal ectopic Purkinje-related premature contractions syndrome is associated with SCN5A mutation which in our case (R222Q) is the most common described. Flecainide can be an appropriate treatment option when ablation is ineffective. Defibrillator-even a subcutaneous type-could be implanted in cases of LV dysfunction or scar. PVCs suppression by flecainide and restoration of EF implies an arrhythmia-induced mechanism of LV impairment.

Anticoagulation for atrial fibrillation in heart failure patients: balancing between Scylla and Charybdis.

The management of heart failure (HF) and atrial fibrillation (AF) in real-world practice remains a debating issue, while the number of HF patients with AF increase dramatically. While it is unclear if rhythm or rate control therapy is more beneficial and under which circumstances, anticoagulation therapy is the cornerstone of the AF-HF patients' approach. Vitamin-K antagonists were the gold-standard during the past, but currently their usage is limited in specific conditions. Non-vitamin K oral anticoagulants (NOACs) have gained ground during the last ten years and considered as gold-standard of a wide spectrum of HF phenotypes. The current manuscript aims to review the current literature regarding the indications and the optimal choice and usage of NOACs in HF patients with AF.

Myocardial deformation imaging unmasks subtle left ventricular systolic dysfunction in asymptomatic and treatment-naïve HIV patients.

BACKGROUND: Patients infected by the human immunodeficiency virus (HIV) and receiving highly active antiretroviral therapy have a higher incidence of cardiovascular disease than healthy subjects, but little is known about cardiac function in asymptomatic and treatment-naïve patients. We sought to study cardiac function in asymptomatic HIV-infected, treatment-naïve patients. METHODS: We studied 41 HIV-infected and treatment-naïve patients and 20 age- and sex-matched healthy controls. Patients with cardiac symptoms, history of cardiac disease or NT-proBNP >100 pg/mL were excluded. We addressed cardiac function using standard echocardiography along with tissue Doppler (TDI) measurements, including strain/strain rate assessment. RESULTS: Standard echocardiographic parameters did not differ between groups, except for transmitral E wave velocity (64.8 ± 14 cm/s in HIV vs 76.1 ± 10 cm/s in controls, p = 0.002). In contrast, TDI mitral and tricuspid annulus s velocity and all strain/strain rate measurements were significantly lower in HIV patients: s lateral, 10.2 ± 2.4/11.3 ± 0.7, p = 0.011; s septal, 8.1 ± 1.6/8.7 ± 0.8, p = 0.045; s tricuspid, 13.4 ± 2.3/14.9 ± 1.3, p = 0.002; strain/strain rate, septal (strain/strain rate, 15.1 ± 5.7/-0.9 ± 0.3, 25.3 ± 1.7/-1.9 ± 0.2, p < 0.001), anterior (16.7 ± 3/-1.0 ± 0.1, 26.7 ± 1.7/-1.9 ± 0.2, p < 0.001), lateral (16.0 ± 6/-1.0 ± 0.1, 27.5 ± 1.8/-2.2 ± 0.3, p < 0.001) and posterior (15.2 ± 5.8/-1.0 ± 0.2, 26.2 ± 1.8/-2.2 ± 0.3, p < 0.001) left ventricular wall. CONCLUSIONS: HIV infection itself is accompanied by subclinical systolic dysfunction, not apparent to standard echocardiography that can be unmasked though using sensitive echocardiographic techniques.