Incidence Of Atrial Arrhythmias Research Articles

Cardiopulmonary exercise testing in repaired tetralogy of Fallot and supraventricular arrythmias

Abstract Background The arrhythmia burden in adult patients (Ps) with tetralogy of Fallot (TOF) is considerable, being a major late complication in repaired TOF. The incidence of atrial arrhythmias is relatively high and one of the main causes of morbidity. Our aim was to assess which cardiopulmonary exercise testing (CPET) parameters best correlate with supraventricular arrythmias (SVA) to potentially improve identification of high-risk Ps. Methods A single-center retrospective analysis was performed from 2009 to 2018 on adult Ps with repaired TOF who underwent maximal CPET. Ambulatory ECG monitoring was used to analyze the arrhythmic profile. Demographics, standard measures of CPET interpretation, and major cardiovascular outcomes were collected. Multivariate analysis for the prediction of SVA was performed using Cox Regression, by including all statistically significant variables in the univariate analysis and those considered clinically relevant. Results CPET was performed in 63 repaired TOF Ps (57% male, mean age of 34 ± 9 years), with a mean follow-up of 60 ± 33 months. 56% Ps had severe pulmonary regurgitation and 48% Ps underwent pulmonary valve replacement (PVR). Supraventricular arrhythmias occurred in 12 Ps (19%), mainly atrial fibrillation or atrial flutter (67%). There were no statistically significant differences regarding the clinical profile and baseline CPET parameters between both groups, namely: age (p=0.113), male gender proportion (p=0.581), proportion of Ps who underwent PVR (p=0.578), RV systolic dysfunction prevalence (p=0.854) and peak oxygen uptake (p=0.083). VE/VCO2 slope was an independent predictor of SVA (HR 1.41, CI 95% 1.08-1.84, p=0.012). Exercise capacity assessed by estimated metabolic equivalents (METS), as well as the peak heart rate (PHR) during exercise (HR 0.86, CI 95% 0.76-0.96, p=0.007), revealed a protective effect regarding SVA (HR 0.71, CI 95% 0.51-0.98, p=0.045). Neither peak oxygen uptake (p=0.090) nor cardiorespiratory optimal point (p=0.427) showed statistically significant correlation with SVA during follow-up. Ps with a PHR above 165 bpm had a significantly higher survival free of SVA (log-rank p=0.045). Conclusion In our population, VE/VCO2 slope was an independent predictor of SVA during follow-up, while both a higher PHR and a higher exercise capacity had a protective effect. CPET could be an accessible way of improving risk-stratification of TOP Ps and should therefore be included in their routine assessment.

Transcatheter closure of atrial septal defect in the elderly: a systematic review and meta-analysis

ObjectiveDespite the establishment of transcatheter closure as the treatment of choice in adults with secundum atrial septal defects (ASDs), the effectiveness of this approach in the elderly is disputed. This...

Abstract 11055: Outcomes and Progression of Rasopathy-Associated Hypertrophic Cardiomyopathy

Background: RASopathy associated hypertrophic cardiomyopathy (HCM) is a frequent cause of pediatric onset HCM. RAS pathway inhibitors are a precision therapeutic option for RASopathy associated HCM. However, limited understanding of HCM progression and correlation with clinical outcomes currently restrict use to a compassionate basis, primarily in infancy. We hypothesize review of RASopathy associated HCM progression and outcomes will demonstrate burden of disease throughout childhood with the goal to identify high risk populations who may benefit from targeted therapies. Methods: A single-center retrospective review identified 59 patients with a diagnosis of HCM and a RASopathy. Echocardiographic, clinical, and molecular data were collected through chart review with echocardiographic measurements at set time points from neonate to young adult. Results: There was high overall mortality in our cohort (20.3%, n = 12). Cardiac arrest, transplant, or death was significantly higher in patients with heart failure in infancy (defined by need for diuretic use) (p<0.001) (Fig 1A). There were no differences by syndrome or genotype. Pulmonary valve (PV) intervention was 16.9% (n = 10) and largely limited to infancy with median age 0.79 years (IQR 0.34-1.63) at first intervention. Incidence of atrial arrhythmias was 13.6% (n = 8) with median age of onset 0.44 years (IQR 0.35-0.88). Rates of septal myectomy were high (23.7%, n = 14). Myectomies, however, were not limited to infancy with median age at first myectomy 3.10 years (IQR 1.09-10.49) (Fig 1B). 21.4% (n = 3) required repeat myectomy. Conclusions: In contrast to previous research, our data suggest there is significant continued HCM growth outside of infancy as evidenced by high incidence of myectomy throughout childhood and young adulthood with frequent need for repeat myectomy. These suggest potential use of targeted therapies outside of infancy with further study needed to identify high-risk populations.

Transcatheter Atrial Septal Defect Closure Before Versus After Adulthood.

ObjectivesTo evaluate the long-term outcome of patients who underwent percutaneous transcatheter closure of secundum atrial septal defects during teenage life versus adulthood.MethodsThe study included 100 patients with secundum type ASD who were treated by transcatheter closure of their defects 2–5 years before enrollment. The study population was subdivided into 2 equal groups: group 1 who underwent transcatheter closure during teenage life (13–19 years) and group 2 who underwent transcatheter closure after the age of 30 years. The two groups were compared according to resting 12 lead ECG, 24-h Holter ECG and transthoracic echocardiographic findings (Right ventricular size and functions, right atrial size, etc.)ResultsThe study population showed female predominance. The average follow up period was similar in both groups. Adult patients had more frequent right bundle branch block morphology in their resting 12 lead ECG than teenagers (69% versus 45% respectively, p < 0.01). The incidence of arrhythmias encountered in Holter ECG was also significantly higher in the adult group. Premature atrial contractions (PAC) were present in 10 patients (20%) in adult group while 3 patients (6%) had PACs in teenagers’ group with p < 0.01. The mean PAC burden was also higher in the adult group (9% versus 1.3%, p < 0.001). Paroxysmal AF lasting more than 30 seconds was found in 6 patients (12%) in the adult group while 1 patient in teenagers developed AF, p < 0.01. Regarding transthoracic echocardiography, adult patients showed significantly larger RV diameter, indexed RA area, indexed LA volume and more LV diastolic dysfunction. RV systolic functions were better in the teenage group as measured by 2D echocardiography. Adult patients with higher age, bigger defect size and device size had more abnormal ECG and echocardiographic findings.ConclusionEarly trans-catheter closure of secundum ASD during teenage life yields better right ventricular systolic function, better right ventricular size and less incidence of atrial arrhythmia.

Pre-existing cardiovascular disease increases risk of atrial arrhythmia and mortality in cancer patients treated with Ibrutinib

BackgroundIbrutinib is a Bruton’s tyrosine kinase inhibitor used in the treatment of hematological malignancies. The most common cardiotoxicity associated with ibrutinib is atrial arrhythmia (atrial fibrillation and flutter). It is known that patients with cardiovascular disease (CVD) are at an increased risk for developing atrial arrhythmia. However, the rate of atrial arrhythmia in patients with pre-existing CVD treated with ibrutinib is unknown.ObjectiveThis study examined whether patients with pre-existing CVD are at a higher risk for developing atrial arrhythmias compared to those without prior CVD.MethodsA single-institution retrospective chart review of patients with no prior history of atrial arrhythmia treated with ibrutinib from 2012 to 2020 was performed. Patients were grouped into two cohorts: those with CVD (known history of coronary artery disease, heart failure, pulmonary hypertension, at least moderate valvular heart disease, or device implantation) and those without CVD. The primary outcome was incidence of atrial arrhythmia, and the secondary outcomes were all-cause mortality, risk of bleeding, and discontinuation of ibrutinib. The predictors of atrial arrhythmia (namely atrial fibrillation) were assessed using logistic regression. A Cox-Proportional Hazard model was created for mortality.ResultsPatients were followed for a median of 1.1 years. Among 217 patients treated with ibrutinib, the rate of new-onset atrial arrhythmia was nearly threefold higher in the cohort with CVD compared to the cohort without CVD (17% vs 7%, p = 0.02). Patients with CVD also demonstrated increased adjusted all-cause mortality (OR 1.9, 95% CI 1.06-3.41, p = 0.01) and decreased survival probability (43% vs 54%, p = 0.04) compared to those without CVD over the follow-up period. There were no differences in risk of bleeding or discontinuation between the two cohorts.ConclusionsPre-existing cardiovascular disease was associated with significantly higher rates of atrial arrhythmia and mortality in patients with hematological malignancies managed with ibrutinib.

Abstract 10937: Incidence of Cardiac Complications During Index Hospitalisation with COVID-19 in Australia: AUS-COVID Study

Introduction: Cardiac complications of COVID-19 include acute cardiac injury, myopericarditis, cardiomyopathy and arrhythmias. This study aimed to describe the incidence of cardiac complications in patients admitted to hospital with COVID-19 in Australia. Methods: AUS-COVID is a multicentre observational cohort study across 21 Australian hospitals including all index hospitalisations with laboratory-proven COVID-19 in patients aged 18 years or older. All consecutive patients entered in the AUS-COVID Registry by 28 th January 2021 were included in the present study. Results: Six hundred and forty-four hospitalised patients (62.5 ± 20.1 years old, 51.1% male) with COVID-19 were enrolled in the study. Overall in-hospital mortality was 14.3%. Twenty (3.6%) patients developed new atrial fibrillation or flutter during admission and 9 (1.6%) patients were diagnosed with new heart failure or cardiomyopathy. Three (0.5%) patients developed high grade atrioventricular (AV) block. Two (0.3%) patients were clinically diagnosed with pericarditis or myopericarditis. Among the 295 (45.8%) patients with at least one troponin measurement, 99 (33.6%) had a peak troponin above the upper limit of normal (ULN). In-hospital mortality was higher in patients with raised troponin (32.3% vs 6.1%, p&lt;.001). New onset atrial fibrillation or flutter (6.4% vs 1.0%, p=.001) and troponin elevation above the ULN (50.3% vs 16.4%, p&lt;.001) were more common in patients 65 years and older. There was no significant difference in the rate of cardiac complications between males and females. Conclusions: Among patients with COVID-19 requiring hospitalisation in Australia, troponin elevation was common but clinical cardiac sequelae were uncommon. The incidence of atrial arrhythmias and troponin elevation was greatest in patients 65 years and older. Trial registration: AUS-COVID. ACTRN12620000486921. http://www.anzctr.org.au/

Cardiac Complications in Patients Hospitalised With COVID-19 in Australia

ObjectivesDescribe the incidence of cardiac complications in patients admitted to hospital with COVID-19 in Australia.DesignObservational cohort study.SettingTwenty-one (21) Australian hospitals.ParticipantsConsecutive patients aged ≥18 years admitted to hospital with laboratory confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.Main outcome measuresIncidence of cardiac complications.ResultsSix-hundred-and-forty-four (644) hospitalised patients (62.5±20.1 yo, 51.1% male) with COVID-19 were enrolled in the study. Overall in-hospital mortality was 14.3%. Twenty (20) (3.6%) patients developed new atrial fibrillation or flutter during admission and 9 (1.6%) patients were diagnosed with new heart failure or cardiomyopathy. Three (3) (0.5%) patients developed high grade atrioventricular (AV) block. Two (2) (0.3%) patients were clinically diagnosed with pericarditis or myopericarditis. Among the 295 (45.8%) patients with at least one troponin measurement, 99 (33.6%) had a peak troponin above the upper limit of normal (ULN). In-hospital mortality was higher in patients with raised troponin (32.3% vs 6.1%, p<0.001). New onset atrial fibrillation or flutter (6.4% vs 1.0%, p=0.001) and troponin elevation above the ULN (50.3% vs 16.4%, p<0.001) were more common in patients 65 years and older. There was no significant difference in the rate of cardiac complications between males and females.ConclusionsAmong patients with COVID-19 requiring hospitalisation in Australia, troponin elevation was common but clinical cardiac sequelae were uncommon. The incidence of atrial arrhythmias and troponin elevation was greatest in patients 65 years and older.

Abstract 14549: Outcome of Radiofrequency Catheter Ablation of Cavo-tricuspid Isthmus Dependent Flutter in Patients With Adult Congenital Heart Disease

Introduction: Both typical cavo-tricuspid isthmus (CTI) dependent (or its equivalent) and atypical atrial flutter (AFL) are common in adults with congenital heart disease (CHD) either due to its inherent cardiac anatomy or as a result of prior surgical procedures. Radiofrequency catheter ablation is routinely used as a therapeutic option. Hypothesis: Patients with CHD will have an improvement in systemic ventricular ejection fraction and a decreased incidence of atrial arrhythmias after ablation. Methods: A retrospective study was conducted on 99 patients with CHD who underwent ablation for clinical AFL at a single institution between 2010 and 2019. Of these patients, 62 had CTI-AFL. The 2 patients with unspecified CHD were excluded. CHD was divided into 3 categories according to the American College of Cardiology Task Force 1 of the 32nd Bethesda Conference - simple, moderate severity, and great complexity lesions. Outcomes of ablation at 1 year follow up were assessed. Results: Typical counterclockwise CTI-AFL was seen in 50 patients. The mean age was 49.1±13.6 years old with 29 (48.3%) females. Of the 60 patients, 35% (n=21) had simple lesions, 51.7% (n=31) had moderate lesions, and 13.3% (n=8) had great complexity lesions. The mean left or systemic ventricular ejection fraction (EF) significantly improved on follow-up echo among patients with simple CHD (49.1±13.1 to 56.5±4.7%, p=0.018) and moderate CHD (49.5±14.9 to 54±8.5%, p=0.02), but did not change among patients with great complexity CHD (52.5±6 to 52.5±9.25%, p=0.9). There was a significantly increased incidence of atrial fibrillation (9.5% vs. 16.1% vs. 50%, p=0.04) post ablation among simple, moderate, and great complexity lesions, respectively, but no significant difference in the recurrence rate of atrial flutter (p=0.3). Conclusions: Patients who underwent CTI-AFL ablation showed an improvement in EF in patients with simple and moderate CHD. There was also a significantly increased incidence in the development of atrial fibrillation post ablation in CHD with great complexity compared to simple or moderate CHD.

The Short QTc Is a Marker for the Development of Atrial Flutter and Atrial Fibrillation.

A short QT interval has been difficult to define, and there is debate whether it exists outside of an extremely small group of individuals with inherited channelopathies and whether it predicts cardiac arrhythmias. The objective was to identify cases with short QT and their consequences. Our hospital ECG database was screened for cases with a QTc based on the Bazett formula (QTcBZT) of less than 340 ms. The QTc was recalculated using the spline (QTcRBK) formula, which more accurately adjusts for the heart rate and identifies cases based on percentile distribution of the QT interval. The exclusion criteria were presence of bundle branch block, arrhythmias, or electronic pacemakers. An age- and sex-matched cohort was obtained from individuals with normal QT intervals with the same exclusion criteria. There were 28 cases with a short QTc (QTcRBK < 380 ms). The age was 69.6 ± 14.6 years (mean ± SD) (50% males). The QT interval was 305.7 ± 61.1 ms with QTcRBK 308.4 ± 31.4 ms. Subsequent ECGs showed atrial flutter in 21%, atrial fibrillation in 18%, and atrial tachycardia in 4% of cases. Thus, atrial arrhythmias occurred in 43% of cases. This incidence was significantly (p < 0.0001) greater than the incidence of atrial arrhythmias in age- and sex-matched controls. In conclusion, a short QT interval can be readily identified based on the first percentile of the new QTc formula. A short QTc is an important marker for the development of atrial arrhythmias, including atrial flutter and atrial fibrillation, with the former predominating. It should be part of patient assessment and warrants consideration to develop strategies for detection and prevention of atrial arrhythmias.

Prolonged duration of repolarization and decreased conduction velocity in the atrial myocardium after hypothermic ischemia-reperfusion may be related to expressions of inward rectifier potassium channel 2.1 protein and connexin 40.

The study aimed to determine the role of inward rectifier potassium channel 2.1 protein and connexin 40 expressions in regulating the duration of repolarization and conduction velocity of right atrial myocardium in rats following hypothermic ischemia-reperfusion. The Langendorff isolated rat cardiac perfusion models were divided into control (C) and hypothermic ischemia-reperfusion groups, with 8 models in group C and 16 models in group ischemia-reperfusion. Depending on the incidence of atrial arrhythmia after reperfusion, the models in group ischemia-reperfusion were further divided into reperfusion non-atrial arrhythmia or reperfusion atrial arrhythmia subgroup. Right atrial monophasic action potential duration at 50% and 90% of repolarization after 30 minutes of continuous perfusion in group C and group ischemia-reperfusion (T0), 105 minutes of continuous perfusion in group C or after 15 minutes of reperfusion in group ischemia-reperfusion (T1) and 120 minutes of continuous perfusion in group C or 30 minutes of reperfusion in group ischemia-reperfusion (T2) were recorded. Right atrial conduction velocity and effective refractory period were recorded at T2. Then, the expressions of inward rectifier potassium channel 2.1 protein and connexin 40 in the right atrial myocardium were detected. Monophasic action potential duration at 50% and 90% were higher at T1 and T2 than those at T0 in subgroup reperfusion atrial arrhythmia (p < 0.05); monophasic action potential duration at 50% in subgroup reperfusion atrial arrhythmia were larger than group C and subgroup reperfusion non-atrial arrhythmia at T1 and T2 (p < 0.05); monophasic action potential duration at 90% in subgroup reperfusion atrial arrhythmia were larger than group C and subgroup reperfusion non-atrial arrhythmia at T1 and T2 (p < 0.05); effective refractory period in subgroup reperfusion atrial arrhythmia was greater than that in group C and subgroup reperfusion non-atrial arrhythmia, and the conduction velocity and the expressions of inward rectifier potassium channel 2.1 protein and connexin 40 were significantly lower than group C and subgroup reperfusion non-atrial arrhythmia (p < 0.05). The prolonged duration of repolarization and a decrease in conduction velocity of the atrial myocardium occur in rats after hypothermic ischemia-reperfusion. These observed effects may be related to the downregulated expressions of connexin 40 and inward rectifier potassium channel 2.1.

Intra-procedural arrhythmia during cardiac catheterization: A systematic review of literature.

BACKGROUNDCardiac catheterization is among the most performed medical procedures in the modern era. There were sporadic reports indicating that cardiac arrhythmias are common during cardiac catheterization, and there are risks of developing serious and potentially life-threatening arrhythmias, such as sustained ventricular tachycardia (VT), ventricular fibrillation (VF) and high-grade conduction disturbances such as complete heart block (CHB), requiring immediate interventions. However, there is lack of systematic overview of these conditions.AIMTo systematically review existing literature and gain better understanding of the incidence of cardiac arrhythmias during cardiac catheterization, and their impact on outcomes, as well as potential approaches to minimize this risk.METHODSWe applied a combination of terms potentially used in reports describing various cardiac arrhythmias during common cardiac catheterization procedures to systematically search PubMed, EMBASE and Cochrane databases, as well as references of full-length articles.RESULTSDuring right heart catheterization (RHC), the incidence of atrial arrhythmias (premature atrial complexes, atrial fibrillation and flutter) was low (< 1%); these arrhythmias were usually transient and self-limited. RHC associated with the development of a new RBBB at a rate of 0.1%-0.3% in individuals with normal conduction system but up to 6.3% in individuals with pre-existing left bundle branch block. These patients may require temporary pacing due to transient CHB. Isolated premature ventricular complexes or non-sustained VT are common during RHC (up to 20% of cases). Sustained ventricular arrhythmias (VT and/or VF) requiring either withdrawal of catheter or cardioversion occurred infrequently (1%-1.3%). During left heart catheterizations (LHC), the incidence of ventricular arrhythmias has declined significantly over the last few decades, from 1.1% historically to 0.1% currently. The overall reported rate of VT/VF in diagnostic LHC and coronary angiography is 0.8%. The risk of VT/VF was higher during percutaneous coronary interventions for stable coronary artery disease (1.1%) and even higher for patients with acute myocardial infarctions (4.1%-4.3%). Intravenous adenosine and papaverine bolus for fractional flow reserve measurement, as well as intracoronary imaging using optical coherence tomography have been reported to induce VF. Although uncommon, LHC and coronary angiography were also reported to induce conduction disturbances including CHB.CONCLUSIONCardiac arrhythmias are common and potentially serious complications of cardiac catheterization procedures, and it demands constant vigilance and readiness to intervene during procedures.

Availability of a novel cardiotoxicity evaluation system using human induced pluripotent stem cell-derived atrial-like myocytes

It is reported that the incidence of atrial arrhythmias has been increasing year by year and it might increase from now on. Although not only aging but pharmaceutical drug treatments might relate to atrial arrhythmias, experimental method to detect drug-induced atrial arrhythmias has not been established so far. Therefore, we induced differentiation of atrial-like cardiomyocytes from human induced pluripotent stem (iPS) cell, and clarified their characteristics and verified their dug responsiveness. Atrial-like cardiomyocytes were induced by adding retinoic acid (RA) during the process of myocardial differentiation, and their character was compared to RA-untreated cardiomyocytes. In gene expression and membrane potential analysis, it was confirmed that the cells with or without RA treatment have the characters of atrial or ventricular like cardiomyocytes, respectively. In addition, it was also confirmed that atrial-like cardiomyocytes induced reentry-like conduction disorder, which is atrial arrhythmias. Furthermore, as a result of examining the responsiveness of various ion channel inhibitors using these cells, the inhibition of ultra-rapid delayed rectifier potassium current (IKur) specifically existed in atrial muscle induced prolongation of PWD30cF (membrane potential duration at 30% depolarization corrected by Fridericia formula) only in atrial-like cardiomyocytes. In addition, ventricular-like cardiomyocytes alone exhibited an early after depolarization by treatment of rapid rectifier potassium current (IKr) inhibitor which induced ventricular arrhythmia in clinical situation. Based on above evidences, current evaluation systems using human iPS cell-derived atrial-like cardiomyocytes might be a valuable tool for drug-induced atrial arrhythmias.

Impact of severe OSA on pharmacoinvasive treatment in ST elevation myocardial infarction patients.

The negative association between obstructive sleep apnea (OSA) and adverse cardiovascular outcomes in patients undergoing percutaneous coronary intervention (PCI) is well documented. However, little is known about the influence of OSA on fibrinolytic therapy. The aim of this study was to evaluate the impact of severe OSA on pharmacoinvasive treatment in ST elevation myocardial infarction (STEMI) patients. We enrolled consecutive STEMI patients without previous vascular disease, heart failure, or OSA diagnosis. All patients underwent either a pharmacoinvasive therapy or primary PCI. Syntax score (SS) was calculated for all patients, and a full bedside polysomnography was performed in the first 72h of admission. In-hospital events and 30days readmissions were analyzed. The sample included 116 patients, 87 men. Patients with severe OSA were older (p = 0.01), had higher neck and abdominal circumferences (p < 0.01), and had higher BMI (p < 0.01). They also had lower reperfusion rates post-fibrinolysis (20 vs. 65%; p = 0.001), higher SS (20.2 ± 11.2 vs. 14.6 ± 10.6; p = 0.03), lower left ventricle ejection fraction (45 ± 8 vs. 51 ± 10%; p = 0.02), and a higher incidence of atrial arrhythmias (4 vs. 21%; p = 0.02). STEMI patients with severe OSA presented with threefold increase in the risk for at least one adverse outcome. Regression analysis showed that both severe OSA and hypertension were independent predictors of higher SS. Severe OSA was associated with a poor outcome after pharmacoinvasive treatment in STEMI patients.

P1883Arrhythmias in transplanted hearts: Lessons from Europes largest cohort of patients who underwent orthotopic heart transplantation

Abstract Introduction Cardiac arrhythmias are regulary seen in patients following orthotopic heart transplantation (OHT). So far, there is no data available about the prevalence in a large cohort. Methods We retrospectively screened our database for subjects with OHT who received inpatient or outpatient treatment in our center between January 2000 and December 2018. All these patients were carefully reviewed with special attention to rhythm disturbances after successful transplantation. Results We identified a total number of 1890 subjects with history of OHT being treated in our center during the pre-defined time-period. The prevalence of supraventricular tachycardias was as follows: atrial fibrillation/atypical flutter and atrial ectopy 10%, AV-node-re-entry tachycardia 3%, typical atrial flutter 2% and higher degree AV-Block or Sick-Sinus-Syndrom (SSS) was 6%. Sustained ventricular tachycardia or ventricular premature contractions were present in 2%. Regarding the patients with arrhythmias, 13% received catheter ablation for arrhythmias, thereof 53% an atrial ablation (24% left atrial ablation), the remainder received a ventricular ablation. Conclusion In this very large cohort and following a long observational time, there was a higher incidence of atrial arrhythmias in patients following OHT as reported in healthy subjects with an emphasis on atrial fibrillation and flutter. This data gives a valuable background information on morbidity following OHT.

Oral Milrinone for the Treatment of Right Ventricular Failure in LVAD Patients

Purpose Early and late right ventricular failure (RVF) are major complications during left ventricular assist device (LVAD) support. Therapies to treat RVF are limited, leading to significant morbidity and increased mortality. Intravenous inotropes are a therapy for severe, persistent cases of RVF, but long-term use carries significant risks of infection and thrombosis associated with venous access. CRD-102 is a novel, extended-release form of oral milrinone. The aim of this study is to evaluate the safety of CRD-102 in LVAD patients with chronic RVF. Methods This is a Phase IIa, non-randomized, open-label study of CRD-102. Patients were eligible if they had a durable LVAD for more than 30 days, evidence of right ventricular dysfunction on echocardiogram, an implantable cardioverter defibrillator (ICD) and a right atrial pressure ≥ 12 mmHg. Patients with ongoing ventricular arrhythmias or uncontrolled atrial fibrillation were excluded. Hemodynamics, echocardiographic measures, ICD interrogation and biomarkers were measured before and during a 2-week period of treatment with CRD-102. Results Six patients were enrolled with mean age 64 ± 10 years, 4 male. The average duration of LVAD support was 5.0 ± 2.3 years. At baseline, mean tricuspid annular plane systolic excursion was 9.9 ± 1.3 mm, right atrial pressure was 16 ± 4 mmHg and pulmonary artery pulsatility index was 1.0 ± 0.4. Five patients completed the study and had no ventricular arrhythmias or increased incidence of atrial arrhythmias during the study period (ICD interrogation). One patient stopped study medication after an ICD shock due to ventricular fibrillation while potassium level was 2.8 mmol/L. There were no other adverse events related to therapy. During treatment, cardiac output significantly improved (5.0 ± 1.3 to 6.4 ± 1.7 L/min, p=0.008) while other hemodynamic parameters were unchanged. NT-proBNP numerically improved during the therapy, but did not reach statistical significance (1570 ± 902 to 1068 ± 390 pg/mL, p=0.3). Patient-reported quality of life improved during support. Conclusion Extended-release oral milrinone has an acceptable safety profile. Further studies are warranted to investigate the efficacy of this therapy for chronic RVF in LVAD patients.

INCIDENCE OF ATRIAL FIBRILLATION IN BLACK PATIENTS POST ATRIAL FLUTTER ABLATION

Background: Black patients have a lower incidence of atrial arrhythmias both atrial fibrillation (AF) and atrial flutter (AFL) despite having the same or a greater number of traditional risk factors. The incidence of atrial fibrillation after cavotricuspid isthmus (CTI) ablation in patients with

A Randomized Trial of Catheters of Different Lengths to Achieve Right Atrium Versus Superior Vena Cava Placement for Continuous Renal Replacement Therapy

The aim was to assess whether inserting a longer soft silicone short-term dialysis catheter targeting tip placement in the right atrium could improve dialyzer circuit life span compared with inserting a shorter dialysis catheter targeting tip placement in the superior vena cava. Randomized unblinded controlled study. A tertiary multidisciplinary intensive care unit enrolling 100 critically ill patients requiring continuous renal replacement therapy (CRRT). Placement of longer (20-24 cm) versus shorter dialysis catheters (15-20 cm) within one of the major thoracic veins for initiation of CRRT. The primary study outcome was duration of dialysis circuit life span. Secondary outcomes included delivered daily dialysis dose, incidence and cause of CRRT circuit failure, complications potentially related to the position of the short-term dialysis catheter, mortality, and patient length of stay. Placing the longer dialysis catheters was associated with an increased average dialyzer life span of 6.5 hours (24 hours [25th-75th percentile, 11-32] vs 17.5 hours [25th-75th percentile, 8-23]; P = 0.001), improved delivered daily dialysis dose (91% [25th-75th percentile, 85%-100%] vs 81% [25th-75th percentile, 72%-97%]; P < 0.001), and reduced number of dialyzers clotted (2.3 vs 3.6; P = 0.04) or circuits taken down due to vascular access problem (0.19 vs 0.53; P = 0.04) per patient compared with placing shorter dialysis catheters. The incidence of atrial arrhythmias was similar between groups (28% vs 21%; P = 0.6) and the only mechanical complication was the malposition of one dialysis catheter tip in the longer dialysis catheter group. Single-center study design. The use of longer soft silicone short-term dialysis catheters targeting right atrial placement appeared to be safe and could improve dialyzer life span and daily dialysis dose of CRRT delivered compared with the use of shorter catheters targeting superior vena cava placement.

Late Arrhythmias Following Fontan Surgery

The incidence of atrial arrhythmias following Fontan repairs varies by the type of surgery and duration of follow-up. The incidence of late atrial tachycardia has been reduced from 60% to less than 20% by surgical modifications. Late ventricular tachycardia is reported in 3% to 12% of patients. Aggressive efforts to eliminate tachycardia and improve hemodynamics may improve clinical status.

Cor triatriatum and lipomatous hypertrophy of the interatrial septum in the elderly: a case report

Cor triatriatum is a rare congenital heart defect characterized by the presence of a fibromuscular membrane dividing the left atrium into two distinct chambers. Lipomatous hypertrophy of the atrial septum is an infrequently observed benign abnormality caused by large fatty tissue deposits in the interatrial septum. An increased incidence of atrial arrhythmias is described in both pathologies, while a significant obstruction of blood flow mimicking mitral stenosis is typically manifested in cor triatriatum. We report the case of a 75-year-old woman with a previously undescribed association of the above stated abnormalities detected by both transthoracic and transeosophageal echocardiography. Diagnosis was confirmed by means of computed tomography. The singular physiologic and anatomic factors underlying survival until such a late age are described. The diagnostic, therapeutic and surgical management is discussed and a short review of the literature performed.

Statins as Antiarrhythmics: A Systematic Review Part I: Effects on Risk of Atrial Fibrillation

Recent studies have demonstrated that statins may possess antiarrhythmic properties in addition to their lipid-lowering effects. Studies which reported the association of statins with the incidence of atrial arrhythmias were identified through a systematic review of published literature. One randomized, placebo-controlled trial of 200 patients undergoing cardiac surgery showed that atorvastatin decreased the incidence of postoperative atrial fibrillation by 61%. Observational studies in patients with stable coronary disease, left ventricular dysfunction, or those undergoing cardiac or noncardiac surgery show that statin therapy is associated with an approximately 50% lower rate of atrial fibrillation. Two small randomized trials reported conflicting results: one showing that atorvastatin reduced the recurrence of AF after electrical cardioversion and the other finding that pravastatin did not. Published data suggests that statins may possess antiarrhythmic properties that reduce the propensity for atrial fibrillation. Most of this data is observational; more randomized, placebo-controlled trials are needed.