Investigating the use of finerenone in children with chronic kidney disease and proteinuria: design of the FIONA and open-label extension studies.

INTRODUCTION: Proteinuria is a modifiable risk factor for chronic kidney disease (CKD) progression in children. Finerenone, a selective, non-steroidal, mineralocorticoid receptor antagonist (MRA) has been approved to treat adults with CKD associated with type 2 diabetes mellitus (T2DM) following results from the phase III clinical trials FIDELIO-DKD (NCT02540993) and FIGARO-DKD (NCT02545049). In a pre-specified pooled analysis of both studies (N = 13,026), finerenone was shown to have an acceptable safety profile and was efficacious in decreasing the risk of adverse kidney and cardiovascular outcomes and of proteinuria. OBJECTIVE: FIONA and the associated open-label extension (OLE) study aim to demonstrate that combining finerenone with an angiotensin-converting enzyme inhibitor (ACEi) or angiotensin receptor blocker (ARB) is safe, well-tolerated, and effective in sustainably reducing urinary protein excretion in children with CKD and proteinuria. DESIGN: FIONA (NCT05196035; Eudra-CT: 2021-002071-19) is a randomized (2:1), double-blind, placebo-controlled, multicenter, phase III study of 6 months' duration in approximately 219 pediatric patients. Patients must have a clinical diagnosis of CKD (an eGFR ≥ 30 mL/min/1.73 m2 if ≥ 1 to < 18 years or a serum creatinine level ≤ 0.40 mg/dL for infants 6 months to < 1 year) with significant proteinuria despite ACEi or ARB usage. The primary objective is to demonstrate that finerenone, added to an ACEi or ARB, is superior to placebo in reducing urinary protein excretion. FIONA OLE (NCT05457283; Eudra-CT: 2021-002905-89) is a single-arm, open-label study, enrolling participants who have completed FIONA. The primary objective of FIONA OLE is to provide long-term safety data. FIONA has two primary endpoints: urinary protein-to-creatinine ratio (UPCR) reduction of ≥ 30% from baseline to day 180 and percent change in UPCR from baseline to day 180. A sample size of 198 participants (aged 2 to < 18 years) in FIONA will provide at least 80% power to reject the null hypothesis of either of the two primary endpoints. CONCLUSION: FIONA is evaluating the use of finerenone in children with CKD and proteinuria. Should safety, tolerability, and efficacy be demonstrated, finerenone could become a useful additional therapeutic agent in managing proteinuria and improving kidney outcomes in children with CKD. TRIAL REGISTRATION: ClinicalTrials.gov NCT05196035. Registered on 19 January 2022.

Finerenone in Hispanic Patients With CKD and Type 2 Diabetes: A Post Hoc FIDELITY Analysis.

Rationale & Objective: In FIDELITY, finerenone improved cardiorenal outcomes in patients with chronic kidney disease (CKD) and type 2 diabetes. This analysis explores the efficacy and safety of finerenone in Hispanic patients. Study Design: Post hoc analysis of the FIDELITY prespecified pooled analysis of the FIDELIO-DKD and FIGARO-DKD randomized control trials. Setting & Participants: Patients with type 2 diabetes and CKD (urinary albumin-to-creatinine ratio [UACR] of ≥30 to <300 mg/g and estimated glomerular filtration rate [eGFR] of ≥25-≤90 mL/min/1.73 m2, or UACR of ≥300 to ≤5,000 and eGFR of ≥25 mL/min/1.73 m2) on optimized renin-angiotensin system blockade. Intervention: Finerenone or placebo. Outcomes: Cardiovascular composite (cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for heart failure); kidney composite (kidney failure, sustained ≥57% eGFR decline, or renal death); change in UACR. Results: Of 13,026 patients, 2,099 (16.1%) self-identified as Hispanic. Median follow-up was 3.0 years. The cardiovascular composite outcome occurred in 10.0% of Hispanic patients receiving Finerenone and in 12.3% of Hispanic patients receiving placebo (HR, 0.80; 95% CI, 0.62-1.04). This was consistent with non-Hispanic patients (HR, 0.87; 95% CI, 0.79-0.97; Pinteraction= 0.59). The kidney composite outcome occurred in 6.5% and 6.6% of Hispanic patients with finerenone and placebo, respectively (HR, 0.94; 95% CI, 0.67-1.33). The risk reduction was consistent with that observed in non-Hispanic patients (HR, 0.75; 95% CI, 0.64-0.87; Pinteraction= 0.22). Finerenone reduced UACR by 32% at month 4 in both Hispanic and non-Hispanic patients versus placebo (P < 0.001 for both patient groups). The safety profile of finerenone and incidence of hyperkalemia was similar between Hispanic and non-Hispanic patient groups. Limitations: Small sample size, short follow-up time, and lower treatment adherence in the Hispanic population. Conclusions: Overall, the efficacy and safety of finerenone were similar in Hispanic and non-Hispanic patients with CKD and type 2 diabetes. Funding: Bayer AG. Trial Registration: ClinicalTrials.gov identifier: NCT02540993, NCT02545049. Plain-Language Summary: Chronic kidney disease (CKD) in patients with type 2 diabetes occurs more frequently in Hispanic patients than in non-Hispanic patients, with a more rapid progression to kidney failure. Treatment with finerenone reduces the risk of having a kidney or heart event (such as starting dialysis or having a heart attack) in patients with CKD and type 2 diabetes. Because clinical trials that investigate treatments for CKD and type 2 diabetes have not included enough Hispanic patients, the benefits of treatments particularly for Hispanic patients are frequently unknown. This study explores the benefits of finerenone in Hispanic patients. Overall, the study shows that finerenone can provide kidney and heart benefits in Hispanic patients with CKD and type 2 diabetes, as it does in non-Hispanic patients.

The impact of obesity on cardiovascular and kidney outcomes in patients with chronic kidney disease and type 2 diabetes treated with finerenone: Post hoc analysis of the FIDELITY study.

AIM: To assess the effect of finerenone on the risk of cardiovascular and kidney outcomes in patients with chronic kidney disease and type 2 diabetes, with and without obesity. MATERIALS AND METHODS: A post hoc analysis of the prespecified pooled FIDELITY dataset assessed the association between waist circumference (WC), composite cardiovascular and kidney outcomes, and the effects of finerenone. Participants were stratified by WC risk groups (representing visceral obesity) as low-risk or high-very high-risk (H-/VH-risk). RESULTS: Of 12 986 patients analysed, 90.8% occupied the H-/VH-risk WC group. Incidence of the composite cardiovascular outcome was similar between finerenone and placebo in the low-risk WC group (hazard ratio [HR] 1.03; 95% confidence interval [CI], 0.72-1.47); finerenone reduced the risk in the H-/VH-risk WC group (HR 0.85; 95% CI, 0.77-0.93). For the kidney outcome, the risk was similar in the low-risk WC group (HR 0.98; 95% CI, 0.66-1.46) and reduced within the H-/VH-risk WC group (HR 0.75; 95% CI, 0.65-0.87) with finerenone versus placebo. There was no significant heterogeneity between the low-risk and H-/VH-risk WC groups for cardiovascular and kidney composite outcomes (P interaction = .26 and .34, respectively). The apparent greater benefit of finerenone on cardiorenal outcomes but lack of significant heterogeneity observed in H-/VH-risk WC patients may be because of the small size of the low-risk group. Adverse events were consistent across WC groups. CONCLUSION: In FIDELITY, benefits of finerenone in lowering the risk of cardiovascular and kidney outcomes were not significantly modified by patient obesity.

Finerenone efficacy in patients with chronic kidney disease, type 2 diabetes and atherosclerotic cardiovascular disease.

AIMS: Finerenone, a selective, non-steroidal mineralocorticoid receptor antagonist, improves cardiovascular (CV) and kidney outcomes in patients with type 2 diabetes (T2D) and chronic kidney disease (CKD). This subgroup analysis of FIDELITY, a pre-specified, pooled, individual patient-data analysis of FIDELIO-DKD (NCT02540993) and FIGARO-DKD (NCT02545049), compared finerenone vs. placebo in patients with and without baseline history of atherosclerotic CV disease (ASCVD). METHODS AND RESULTS: Outcomes included a composite CV outcome [CV death, non-fatal myocardial infarction, non-fatal stroke, or hospitalization for heart failure (HHF)]; CV death or HHF; a composite kidney outcome (kidney failure, sustained estimated glomerular filtration rate decrease ≥57%, or kidney-related death); all-cause mortality; and safety by baseline history of ASCVD.Of 13 026 patients, 5935 (45.6%) had a history of ASCVD. The incidence of the composite CV outcome, CV death or HHF, and all-cause mortality was higher in patients with ASCVD vs. those without, with no difference between groups in the composite kidney outcome. Finerenone consistently reduced outcomes vs. placebo in patients with and without ASCVD (P-interaction for the composite CV outcome, CV death or HHF, the composite kidney outcome, and all-cause mortality 0.38, 0.68, 0.33, and 0.38, respectively). Investigator-reported treatment-emergent adverse events were consistent between treatment arms across ASCVD subgroups. CONCLUSION: Finerenone reduced the risk of CV and kidney outcomes consistently across the spectrum of CKD in patients with T2D, irrespective of prevalent ASCVD.

CART19-BE-01: A Multicenter Trial of ARI-0001 Cell Therapy in Patients with CD19+ Relapsed/Refractory Malignancies.

We evaluated the administration of ARI-0001 cells (chimeric antigen receptor T cells targeting CD19) in adult and pediatric patients with relapsed/refractory CD19+ malignancies. Patients received cyclophosphamide and fludarabine followed by ARI-0001 cells at a dose of 0.4-5 × 106 ARI-0001 cells/kg, initially as a single dose and later split into 3 fractions (10%, 30%, and 60%) with full administration depending on the absence of cytokine release syndrome (CRS). 58 patients were included, of which 47 received therapy: 38 with acute lymphoblastic leukemia (ALL), 8 with non-Hodgkin's lymphoma, and 1 with chronic lymphocytic leukemia. In patients with ALL, grade ≥3 CRS was observed in 13.2% (26.7% before versus 4.3% after the amendment), grade ≥3 neurotoxicity was observed in 2.6%, and the procedure-related mortality was 7.9% at day +100, with no procedure-related deaths after the amendment. The measurable residual disease-negative complete response rate was 71.1% at day +100. Progression-free survival was 47% (95% IC 27%-67%) at 1 year: 51.3% before versus 39.5% after the amendment. Overall survival was 68.6% (95% IC 49.2%-88%) at 1 year. In conclusion, the administration of ARI-0001 cells provided safety and efficacy results that are comparable with other academic or commercially available products. This trial was registered as ClinicalTrials.gov: NCT03144583.

Patient-reported outcomes in the SOluble guanylate Cyclase stimulatoR in heArT failurE patientS with PRESERVED ejection fraction (SOCRATES-PRESERVED) study.

AIMS: Exploratory assessment of the potential benefits of the novel soluble guanylate cyclase stimulator vericiguat on health status in patients with heart failure (HF) with preserved ejection fraction. METHODS AND RESULTS: The SOCRATES-PRESERVED trial randomized patients with chronic HF and ejection fraction ≥ 45% within 4 weeks of decompensation to 12 weeks of treatment with titrated doses of vericiguat (1.25, 2.5, 5, and 10 mg once daily) or placebo. Health status was assessed with the disease-specific Kansas City Cardiomyopathy Questionnaire (KCCQ) and the generic health-related quality of life measure EQ-5D. In total, 477 patients were randomized 12.9 ± 9.0 days after hospitalization or if requiring outpatient treatment with intravenous diuretics for HF. Baseline KCCQ clinical summary score (CSS), a combination of symptom and physical function domains, was 52.3 ± 20.4 in the 10 mg arm and 54.1 ± 23.0 in placebo, and EQ-5D US index score was 0.74 ± 0.2 and 0.73 ± 0.2, respectively. A larger proportion of patients treated with vericiguat in the 10 mg arm, compared with placebo, achieved clinically meaningful improvements in KCCQ-CSS (82.0% vs. 59.0%, number needed to treat = 4.35, P = 0.0052). Important domains of the KCCQ as well as EQ-5D scores demonstrated a dose-dependent relationship with vericiguat. In the 10 mg arm, the mean physical limitations domain increased by +17.2 ± 19.1 at 12 weeks, compared with +4.5 ± 21.6 in placebo (P = 0.0009). The EQ-5D US index score increased by +0.064 ± 0.167 in the 10 mg arm, compared with a decrease of -0.009 ± 0.195 in placebo (P = 0.0461). Improvements in KCCQ and EQ-5D scores paralleled physician-assessed NYHA class and clinical congestion. CONCLUSION: Vericiguat, in exploratory hypothesis-generating analyses, was associated with clinically important improvements in patients' health status, as assessed by the KCCQ and EQ-5D. Further studies should be conducted to test the hypothesis that vericiguat improves physical functioning and health-related quality of life in patients with HF with preserved ejection fraction.

Vericiguat in patients with worsening chronic heart failure and preserved ejection fraction: results of the SOluble guanylate Cyclase stimulatoR in heArT failurE patientS with PRESERVED EF (SOCRATES-PRESERVED) study.

Aims: To determine tolerability and the optimal dose regimen of the soluble guanylate cyclase stimulator vericiguat in patients with chronic heart failure and preserved ejection fraction (HFpEF). Methods and results: SOCRATES-PRESERVED was a prospective, randomized, placebo-controlled double-blind, Phase 2b dose-finding study in patients with HFpEF (ejection fraction ≥ 45%). Patients received vericiguat once daily at 1.25 or 2.5 mg fixed doses, or 5 or 10 mg titrated from a 2.5 mg starting dose, or placebo for 12 weeks. The two primary endpoints were change from baseline in log-transformed N-terminal pro-B-type natriuretic peptide (NT-ProBNP) and left atrial volume (LAV) at 12 weeks. Patients (N = 477; 48% women; mean age 73 ± 10 years; baseline atrial fibrillation 40%) were randomized within 4 weeks of HF hospitalization (75%) or outpatient treatment with intravenous diuretics for HF (25%) to vericiguat (n = 384) or placebo (n = 93). In the pooled three highest dose arms change in logNT-proBNP (vericiguat: +0.038 ± 0.782 log(pg/mL), n = 195; placebo: -0.098 ± 0.778 log(pg/mL), n = 73; one-sided P = 0.8991, two-sided P = 0.2017), and change in LAV [vericiguat: -1.7 ± 12.8 mL (n = 194); placebo: -3.4 ± 12.7 mL (n = 67), one-sided P = 0.8156, two-sided P = 0.3688] were not different from placebo. Vericiguat was well tolerated (adverse events: vericiguat 10 mg arm, 69.8%; placebo, 73.1%), with low discontinuation rates in all groups, and no changes in blood pressure at 10 mg compared with placebo. The pre-specified exploratory endpoint of Kansas City Cardiomyopathy Questionnaire Clinical Summary Score improved in the vericiguat 10 mg arm by mean 19.3 ± 16.3 points [median 19.8 (interquartile range 10.4-30.7)] from baseline (mean difference from placebo 9.2 points). Conclusion: Vericiguat was well tolerated, did not change NT-proBNP and LAV at 12 weeks compared with placebo but was associated with improvements in quality of life in patients with HFpEF. Given the encouraging results on quality of life, the effects of vericiguat in patients with HFpEF warrant further study, possibly with higher doses, longer follow-up and additional endpoints.

PATENT PLUS: a blinded, randomised and extension study of riociguat plus sildenafil in pulmonary arterial hypertension.

PATENT PLUS evaluated the safety and efficacy of riociguat in combination with sildenafil in pulmonary arterial hypertension patients. Patients receiving sildenafil (20 mg three times daily) were randomised to placebo or riociguat (up to 2.5 mg three times daily) for 12 weeks. The primary outcome was maximum change in supine systolic blood pressure (SBP) from baseline within 4 h of dosing. Secondary objectives comprised additional blood pressure, heart rate and exploratory efficacy variables, and safety. Patients could enter a long-term extension (LTE), where all patients received riociguat plus sildenafil. There was no difference in maximum change in supine SBP from baseline within 4 h between the riociguat (n=12) (mean±sd baseline: -20.2±15.3 mmHg; week 12: -20.7±18.0 mmHg) and placebo groups (n=6) (-7.6±3.9 and -20.2±12.9 mmHg, respectively). Changes in standing SBP and supine or standing diastolic blood pressure were also not different. Combination therapy showed no favourable effects on exploratory clinical parameters, including haemodynamics and exercise capacity. In the LTE, there were high rates of discontinuation due to hypotension and three (18%) deaths (not considered study drug-related by the investigator). There were potentially unfavourable safety signals with sildenafil plus riociguat and no evidence of a positive benefit/risk ratio. Concomitant use of riociguat with phosphodiesterase-5 inhibitors is therefore contraindicated.

Rationale and design of the SOluble guanylate Cyclase stimulatoR in heArT failurE Studies (SOCRATES).

AIMS: The clinical outcomes for patients with worsening chronic heart failure (WCHF) remain exceedingly poor despite contemporary evidence-based therapies, and effective therapies are urgently needed. Accumulating evidence supports augmentation of cyclic guanosine monophosphate (cGMP) signalling as a potential therapeutic strategy for HF with reduced or preserved ejection fraction (HFrEF and HFpEF, respectively). Direct soluble guanylate cyclase (sGC) stimulators target reduced cGMP generation due to insufficient sGC stimulation and represent a promising method for cGMP enhancement. METHODS: The phase II SOluble guanylate Cyclase stimulatoR in heArT failurE Study (SOCRATES) programme consists of two randomized, parallel-group, placebo-controlled, double-blind, multicentre studies, SOCRATES-REDUCED (in patients with LVEF <45%) and SOCRATES-PRESERVED (in those with LVEF ≥ 45%), that will explore the pharmacodynamic effects, safety and tolerability, and pharmacokinetics of four dose regimens of the once-daily oral sGC stimulator vericiguat (BAY 1021189) over 12 weeks compared with placebo. These studies will enrol patients stabilized during hospitalization for HF at the time of discharge or within 4 weeks thereafter. The primary endpoint in SOCRATES-REDUCED is change in NT-proBNP at 12 weeks. The primary endpoints in SOCRATES-PRESERVED are change in NT-proBNP and left atrial volume at 12 weeks. PERSPECTIVES: SOCRATES will be the first programme to enrol specifically both inpatients and outpatients with WCHF and patients with reduced or preserved ejection fraction. Results will inform the benefits of pursuing subsequent event-driven clinical outcome trials with sGC stimulators in this patient population.

Riociguat for patients with pulmonary hypertension caused by systolic left ventricular dysfunction: a phase IIb double-blind, randomized, placebo-controlled, dose-ranging hemodynamic study.

BACKGROUND: Pulmonary hypertension caused by systolic left ventricular dysfunction is associated with significant morbidity and mortality; however, no treatment is approved for this indication. We hypothesized that riociguat, a novel soluble guanylate cyclase stimulator, would have beneficial hemodynamic effects in patients with pulmonary hypertension caused by systolic left ventricular dysfunction. METHODS AND RESULTS: Overall, 201 patients with heart failure resulting from pulmonary hypertension caused by systolic left ventricular dysfunction were randomized to double-blind treatment with oral placebo or riociguat (0.5, 1, or 2 mg 3 times daily) for 16 weeks in 4 parallel arms. The primary outcome was the placebo-corrected change from baseline at week 16 in mean pulmonary artery pressure. Although the decrease in mean pulmonary artery pressure in the riociguat 2 mg group (-6.1±1.3 mm Hg; P<0.0001 versus baseline) was not significantly different from placebo (P=0.10), cardiac index (0.4 L·min(-1)·m(-2); 95% confidence interval, 0.2-0.5; P=0.0001) and stroke volume index (5.2 mL·m(-2); 95% confidence interval, 2.0-8.4; P=0.0018) were significantly increased without changes in heart rate or systemic blood pressure compared with placebo. Both pulmonary (-46.6 dynes·s(-1)·cm(-5); 95% confidence interval, -89.4 to -3.8; P=0.03) and systemic vascular resistance (-239.3 dynes·s(-1)·cm(-5); 95% confidence interval, -363.4 to -115.3; P=0.0002) were significantly reduced with riociguat 2 mg. Riociguat reduced the Minnesota Living With Heart Failure score (P=0.0002). Discontinuation of treatment was similar between treatment groups. CONCLUSIONS: Although the primary end point of the study was not met, riociguat was well tolerated in patients with pulmonary hypertension caused by systolic left ventricular dysfunction and improved cardiac index and pulmonary and systemic vascular resistance. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01065454.

Physical activity, height, and left atrial size are independent risk factors for lone atrial fibrillation in middle-aged healthy individuals.

AIMS: The aetiology of atrial fibrillation (AF) remains unknown in some patients. The aim of the study was to identify new risk factors for developing lone AF (LAF). METHODS AND RESULTS: A series of 107 consecutive patients younger than 65, seen in the emergency room for an episode of LAF of <48 h duration were included in the study. A group of 107 healthy volunteers matched for age and sex were recruited as controls. All subjects answered a validated questionnaire concerning leisure and occupational activities performed throughout their lifetimes to estimate accumulated hours of physical effort, classified in four levels of intensity. Demographic and echocardiographic measurements were also recorded. There were 69% of males and mean age was 48 +/- 11 years. AF was paroxysmal in 57% and persistent in the remaining 43%. Patients with AF performed more hours of both moderate and heavy intensity physical activity. They also were taller, and had a larger left atria, ventricle, and body surface area. At the multivariable analysis, only moderate and heavy physical activity, height, and anteroposterior atrial diameter were independently associated with LAF. CONCLUSIONS: Accumulated lifetime physical activity, height, and left atrial size are risk factors for LAF in healthy middle-aged individuals.

Is there an anatomical substrate for idiopathic paroxysmal atrial fibrillation? A case-control echocardiographic study.

AIM: Idiopathic paroxysmal atrial fibrillation (AF) occurs in patients with apparently normal heart. Its mechanisms may be complex and are poorly understood. The aim of the study was to evaluate whether patients with idiopathic AF have any structural abnormality that may explain the occurrence of AF. METHODS AND RESULTS: A case-control study was undertaken including 60 consecutive patients (mean age 48 +/- 12 years; 75% men) with idiopathic AF admitted to the emergency department. Sixty sex- and age-matched healthy volunteers made up the control group. An echocardiogram was performed in all patients and volunteers to assess the left atrial (LA) and ventricular (LV) dimensions and valvular function. LV diastolic function was also evaluated by analysis of the LV inflow and pulmonary vein flow velocity patterns and tissue Doppler imaging of the mitral annulus. All AF patients showed normal echocardiographic studies with similar LV dimensions, ejection fraction, and diastolic function when compared with normal controls. However, patients with AF had larger LA dimensions (27 +/- 3 vs. 24 +/- 3 mm/m(2)), LA area (10 +/- 2 vs. 8 +/- 2 mm(2)/m(2)), and LA volume (27 +/- 9 vs. 19 +/- 6 mL/m(2)) (P < 0.05 for all). Among patients with AF, there were no differences in LA size between patients with a first episode or recurrent paroxysmal episodes. CONCLUSION: Patients with idiopathic AF showed larger left atria when compared with controls, there being no differences between patients with a first episode or a recurrence. This suggests the presence of an enhanced substrate to develop idiopathic lone AF.

Incidence of pulmonary vein stenosis in patients submitted to atrial fibrillation ablation: a comparison of the Selective Segmental Ostial Ablation vs the Circumferential Pulmonary Veins Ablation.

INTRODUCTION: Pulmonary vein (PV) stenosis is an important complication of the AF ablation and could be underestimated if their assessment is not systematically done. Selective Segmental Ostial Ablation (SSOA) and Circunferential Pulmonary Veins Ablation (CPVA) have demonstrated efficacy in atrial fibrillation (AF) treatment. In this study the real incidence of PV stenosis in patients (pts) submitted to both SSOA and CPVA was compared. METHODS: Those pts with focal activity and normal left atrial size were submitted to SSOA, remaining pts were submitted to CPVA to treat refractory, symptomatic AF. Contrast enhanced magnetic resonance angiography (MRA) was routinely performed in all patients 4 months after the procedure. RESULTS: A series of 73 consecutive patients (mean age of 51 +/- 11 years; 75% male) were included. SSOA was performed in 32 patients, and the remaining 41 patients underwent to CPVA, obtaining similar efficacy rates (72% vs 76% arrythmia free probability at 12 months; log rank test p = NS). Six patients had a significant PV stenosis, all in SSOA group none in CPVA group (18.8% vs 0%; p = 0.005). All patients were asymptomatic and the stenosis was detected in routine MRA. No predictors of stenosis has been identified analysing patient procedure characteristics. CONCLUSION: PV stenosis is a potential complication of SSOA not seen in CPVA. The study confirms than MRA is useful for identifying patients with asymptomatic PV stenosis.

Orthodromic pacemaker-mediated tachycardia in a biventricular system without an atrial electrode.

Pacemaker-mediated tachycardia is a well-known complication of dual-chamber devices. In this report, we describe for the first time a case of orthodromic pacemaker-mediated tachycardia in a patient in whom a biventricular system without an atrial electrode had been implanted. Retrograde atrial activation was directly produced by the dislodged coronary vein electrode in the AV groove, resulting in simultaneous capture of the left atrium and left ventricle. During tachycardia, AV nodal conduction was via the anterograde pathway of the circuit and limited the ventricular response. Subsequently, right ventricular activation was sensed by the right ventricular electrode that triggered biventricular pacing and left atrial capture, perpetuating the tachycardia. Because the left atrial threshold was higher than the left ventricular threshold, the problem could be resolved easily by lowering the output of the coronary vein electrode.