Right ventricular outflow dysfunction, manifesting as stenosis, regurgitation, or both, is nearly universal in patients with repaired tetralogy of Fallot, precipitating a complex pathophysiological cascade that leads to increasing rates of morbidity and mortality with advancing age. As the number of adolescent and adult patients with repaired tetralogy of Fallot continues to grow as a result of excellent survival during infancy, the need to improve late outcomes has become an urgent priority. This American Heart Association scientific statement provides an update on the current state of knowledge of the pathophysiology, methods of surveillance, risk stratification, and latest available therapies, including transcatheter and surgical pulmonary valve replacement strategies, as well as management of life-threatening arrhythmias. It reviews emerging evidence on the roles of comorbidities and patient-reported outcomes and their impact on quality of life. In addition, this scientific statement explores contemporary evidence for clinical choices such as transcatheter or surgical pulmonary valve replacement, discusses criteria and options for intervention for failing implanted bioprosthetic pulmonary valves, and considers a new approach to determining optimal timing and indications for pulmonary valve replacement.
Background: The heart expresses 2 main subtypes of cAMP-dependent protein kinase (PKA; type I and II) that differ in their regulatory subunits, RIα and RIIα. Embryonic lethality of RIα knockout mice limits the current understanding of type I PKA function in the myocardium. The objective of this study was to test the role of RIα in adult heart contractility and pathological remodeling.
Methods: We measured PKA subunit expression in human heart and developed a conditional mouse model with cardiomyocyte-specific knockout of RIα (RIα-icKO). Myocardial structure and function were evaluated by echocardiography, histology, and ECG and in Langendorff-perfused hearts. PKA activity and cAMP levels were determined by immunoassay, and phosphorylation of PKA targets was assessed by Western blot. L-type Ca2+ current (ICa,L), sarcomere shortening, Ca2+ transients, Ca2+ sparks and waves, and subcellular cAMP were recorded in isolated ventricular myocytes (VMs).
Results: RIα protein was decreased by 50% in failing human heart with ischemic cardiomyopathy and by 75% in the ventricles and in VMs from RIα-icKO mice but not in atria or sinoatrial node. Basal PKA activity was increased ≈3-fold in RIα-icKO VMs. In young RIα-icKO mice, left ventricular ejection fraction was increased and the negative inotropic effect of propranolol was prevented, whereas heart rate and the negative chronotropic effect of propranolol were not modified. Phosphorylation of phospholamban, ryanodine receptor, troponin I, and cardiac myosin-binding protein C at PKA sites was increased in propranolol-treated RIα-icKO mice. Hearts from RIα-icKO mice were hypercontractile, associated with increased ICa,L, and [Ca2+]i transients and sarcomere shortening in VMs. These effects were suppressed by the PKA inhibitor, H89. Global cAMP content was decreased in RIα-icKO hearts, whereas local cAMP at the phospholamban/sarcoplasmic reticulum Ca2+ ATPase complex was unchanged in RIα-icKO VMs. RIα-icKO VMs had an increased frequency of Ca2+ sparks and proarrhythmic Ca2+ waves, and RIα-icKO mice had an increased susceptibility to ventricular tachycardia. On aging, RIα-icKO mice showed progressive contractile dysfunction, cardiac hypertrophy, and fibrosis, culminating in congestive heart failure with reduced ejection fraction that caused 50% mortality at 1 year.
Conclusions: These results identify RIα as a key negative regulator of cardiac contractile function, arrhythmia, and pathological remodeling.
Background: In DanGer Shock (the Danish-German Cardiogenic Shock trial), use of a microaxial flow pump (mAFP) in patients with ST-segment-elevation myocardial infarction-related cardiogenic shock led to lower all-cause mortality but higher rates of renal replacement therapy (RRT). In this prespecified analysis, rates and predictors of acute kidney injury (AKI) and RRT were assessed.
Methods: In this international, randomized, open-label, multicenter trial, 355 adult patients with ST-segment-elevation myocardial infarction-related cardiogenic shock were randomized to mAFP (n=179) or standard care alone (n=176). AKI was defined according to RIFLE criteria (Risk, Injury, Failure, Loss, and End-stage kidney disease) and assessed using logistic regression models. Use of RRT was assessed accounting for the competing risk of death using Fine-Gray subdistribution hazard models.
Results: AKI (RIFLE ≥1) was recorded in 110 patients (61%) in the mAFP group and 79 patients (45%) in the control group (P<0.01); RRT was used in 75 (42%) and 47 (27%) patients, respectively (P<0.01). About two-thirds of the RRTs were initiated within the first 24 hours from admission (n=48 [64%] in the mAFP group and n=31 [66%] in the control group). Occurrence of AKI and RRT were associated with higher 180-day mortality in both study arms. At 180 days, all patients alive were free of RRT. mAFP use was associated with higher rates of RRT, even when accounting for competing risk of death (subdistribution hazard, 1.67 [1.18-2.35]). This association was largely consistent among prespecified subgroups. Allocation to mAFP was associated with lower 180-day mortality irrespective of AKI or RRT (Pinteraction=0.84). Relevant predictors of AKI in both groups comprised reduced left ventricular ejection fraction, baseline kidney function, shock severity, bleeding events, and positive fluid balance. Predictors of AKI specific to mAFP were suction events, higher pump speed, and longer duration of support.
Conclusions: Shock severity, allocation to mAFP, and device-related complications were associated with an increased risk of AKI. AKI was generally associated with higher mortality, but the allocation to mAFP consistently led to lower mortality rates at 180 days irrespective of the occurrence of AKI with or without RRT initiation.
Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01633502.
Background: Primary aldosteronism, characterized by renin-independent aldosterone production, is associated with adverse cardiovascular remodeling and outcomes. Elevated cardiovascular risk is observed even in subclinical forms of primary aldosteronism according to studies conducted primarily in middle-aged and elderly populations. This study aimed to assess whether early changes in primary aldosteronism biomarkers during young adulthood are associated with arterial stiffness and left ventricular mass index (LVMI) before the onset of overt disease.
Methods: The Raine Study is a longitudinal, population-based cohort study in Western Australia that enrolled women during pregnancy. We analyzed the data from the offspring of these women at 17 (2006-2009) and 27 (2016-2018) years of age. Participants with elevated high-sensitivity C-reactive protein (>10 mg/L) and female participants who were on oral contraception were excluded. Pulse wave velocity and aortic augmentation index were measured by SphygmoCor Pulse Wave System at both ages, and aortic distensibility and LVMI were measured by cardiac magnetic resonance imaging at 27 years. Multivariable linear regression was used to examine the relationship between plasma renin, aldosterone, or aldosterone-to-renin ratio and arterial stiffness and LVMI. Mediation analysis was used to test the role of systolic blood pressure.
Results: This study included 859 participants at 17 (38.0% female) and 758 participants at 27 (33.2% female) years of age. Females had lower renin concentration at both 17 (20.7 mU/L versus 25.7 mU/L; P<0.001) and 27 (12.0 mU/L versus 15.4 mU/L; P<0.001) years of age; hence, the aldosterone-to-renin ratio was significantly higher at both 17 (18.2 versus 13.5; P<0.001) and 27 (21.0 versus 15.6; P<0.001) years of age in females compared with males. At 27 years of age, a significant association was detected between aldosterone and LVMI in males (β=0.009 [95% CI, 0.001-0.017]; P=0.027) and between aldosterone-to-renin ratio and LVMI in females (β=0.098 [95% CI, 0.001-0.196]; P=0.050) independently of systolic blood pressure and other confounders. No association was found between primary aldosteronism biomarkers and measures of arterial stiffness (pulse wave velocity, aortic augmentation index, and aortic distensibility) at either age.
Conclusions: Aldosterone concentration and aldosterone-to-renin ratio were positively associated with the LVMI in young males and females, respectively, independently of systolic blood pressure. Long-term follow-up is required to determine whether the relationship persists over time, and clinical trials are needed to assess the cardiovascular benefits of early interventions to block aldosterone.
Aortic stenosis (AS) and coronary artery disease (CAD) frequently coexist and share pathophysiological mechanisms. The proportion of patients with AS and CAD requiring revascularization varies widely because of uncertainty about best clinical practices. Although combined surgical aortic valve replacement and coronary artery bypass grafting has been the standard of care, management options in patients with AS and CAD requiring revascularization have expanded with the advent of transcatheter aortic valve replacement (TAVR). Potential alternative treatment pathways include revascularization before TAVR, concomitant TAVR and percutaneous coronary intervention, percutaneous coronary intervention after TAVR and deferred percutaneous coronary intervention or hybrid procedures. Selection depends on underlying disease severity, antithrombotic treatment strategies, clinical presentation, and symptom evolution after TAVR. In patients undergoing surgical aortic valve replacement, the addition of coronary artery bypass grafting has been associated with improved long-term mortality, especially if CAD is complex. although it is associated with higher periprocedural risk. The therapeutic impact of percutaneous coronary intervention in patients with TAVR is less well-established. The multitude of clinical permutations and remaining uncertainties do not support a uniform treatment strategy for patients with AS and CAD. Therefore, to provide the best possible care for each individual patient, heart teams need to be familiar with the available data on AS and CAD. Herein, we provide an in-depth review of the evidence supporting the decision-making process between transcatheter and surgical approaches and the key elements of treatment selection in patients with AS and CAD.
Background: Ablation strategies for patients with symptomatic atrial fibrillation and isolated pulmonary veins vary and their effects on arrhythmia recurrence remain unclear. A prospective randomized German multicenter trial sought to compare 2 ablation strategies in this patient cohort.
Methods: Patients with atrial fibrillation despite durable pulmonary vein isolation were randomly assigned at 7 centers to undergo low-voltage area ablation using 3-dimensional mapping and irrigated radiofrequency current ablation (group A) or empirical left atrial appendage isolation (LAAI) using the cryoballoon followed by staged interventional left atrial appendage closure (group B). The primary end point was freedom from atrial tachyarrhythmias between 91 and 365 days after index ablation. The study was powered for superiority of LAAI compared with low-voltage area.
Results: Patients (40% women; mean age, 68.8±8 years) with paroxysmal (32%) or persistent atrial fibrillation (68%) were randomized to undergo low-voltage area ablation (n=79) or cryoballoon-guided LAAI (n=82). After a planned interim analysis, enrollment was halted for futility on January 10, 2023. In the LAAI group, 77 of 82 left atrial appendages were successfully isolated with subsequent left atrial appendage closure in 57 patients. Procedure-related complications occurred in 4 (5%) and 11 (13.5%) patients in group A and B, respectively (P=0.10). The median follow-up was 367 days (interquartile range, 359-378). The Kaplan-Meier point estimate for freedom from atrial tachyarrhythmias was 51.7% (CI, 40.9%-65.4%) for group A and 55.5% (CI, 44.4%-69.2%; P=0.8069) for group B.
Conclusions: The current study did not detect superiority of cryoballoon-guided LAAI over low-voltage area ablation in patients with atrial fibrillation despite durable PVI.
Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04056390.