Citations

Abstract Background The right ventricular moderator band-papillary muscle (RV MB-PM) complex has a rich subendocardial network of purkinje fibers which can lead to ventricular arrhythmias (VA)1. Catheter ablation of such arrhythmias is procedurally challenging and there remains limited studies on long-term procedural success. Purpose We aimed to systematically study RV MB-PM complex VA. Methods A single center retrospective study from January 2013 to December 2023 identified 3249 patients who underwent VA ablation. The RV MB-PM complex was targeted in 47 patients. Acute success was defined as suppression of the targeted VA >=30 minutes post ablation. Long-term success was defined as the absence of symptoms, total PVC burden <5% or improvement in EF in patients presenting with isolated PVCs and as freedom from appropriate ICD therapy in patients presenting with malignant PVCs inducing VF, sustained VT or VT storm. Results Mean age was 51.9 ± 16.7 years and 64% were male. 40 (85%) patients had VA targeted from the MB and 7 (15%) from the PM complex (2 anterior, 2 inferior and 3 septal PM). 34 (72%) had no underlying structural heart disease, 3 (6%) ischemic cardiomyopathy and 10 (21%) non-ischemic cardiomyopathy. No patient had delayed gadolinium enhancement in the RV MB-PM complex. VA were inducible in 42 (89%) of patients and activation mapping was used in 9 (19%), pace mapping in 5 (11%) and a combination of activation and pace mapping used in 33 (70%) patients. Intracardiac echocardiography was used in all cases. Pre-QRS duration was 34.0 ± 10.4 ms. Radiofrequency ablation was used in 37 (78.7%) cases, cryotherapy in 4 (8.51%) cases and a combination of the 2 energy sources in 6 (12.8%) cases. In all cases, acute peri-procedural success was achieved. 24 (51.1%) patients presented with isolated PVCs and were followed up for 4.72 ± 3.55 years after their index procedure. 3 patients underwent repeat catheter ablation targeting the same PVC focus but all patients had long term success with a PVC burden of 16.1 ± 12.5% prior to ablation and 2.40 ± 2.44% at last follow-up. 16 patients underwent ablation for recurrent ICD shocks after initially presenting with PVC induced VF. Patients were followed up for 3.22 ± 2.09 years and 14 (88%) patients remained free from ICD therapy. 7 patients had MB ablation for sustained VT and were followed up for 4.06 ± 3.77 years. 5 (71%) patients remained free from ICD therapy. A purkinje potential was seen in 8% (2/24) cases of isolated PVCs and in 39% (9/23) cases of PVC induced VF or VT (p=0.13). Conclusions RV MB-PM VA commonly present with malignant VF and a purkinje potential is more likely to be seen in these cases suggesting different VA mechanisms to isolated PVCs and catheter ablation is an effective long-term strategy.

Abstract Background/Introduction Patients with ATTR-CM can have lower circulating TTR levels, which is associated with worsening of cardiac function and increased risk of cardiovascular mortality.[1] Acoramidis has been shown to reduce cardiovascular mortality and hospitalization, while increasing circulating TTR levels, in the ATTRibute-CM phase 3 study.[2] Purpose I. Evaluate serum TTR levels in participants (pts) receiving acoramidis vs those who received tafamidis in the placebo group in ATTRibute-CM at Month 30. II. Evaluate serum TTR levels in pts who transitioned from placebo+tafamidis to acoramidis in the open-label long term extension (OLE) study. Methods ATTRibute-CM study: Eligible pts with ATTR-CM were randomized in a 2:1 ratio to receive acoramidis or placebo for 30 months. Pts in both groups had the option of initiating open-label, commercially available tafamidis after 12 months in the study. Upon completion of Month 30, pts were invited to participate in the OLE study. In OLE, pts who had previously received acoramidis continued acoramidis, and those who had previously received placebo+tafamidis were switched to acoramidis-only treatment. All pts in the OLE study received acoramidis only. Change in serum TTR levels in ATTRibute-CM and OLE at data cutoff (Oct 9, 2023) are summarised using descriptive statistics. Results In the phase 3 study, efficacy analyses were performed in 611 pts, of which 61 of 409 (14.9%) and 46 of 202 (22.8%) received tafamidis in acoramidis and placebo groups, respectively. The median time until tafamidis initiation was 17.8 and 16.1 months, respectively; median exposure duration was 11.6 and 10.5 months, for acoramidis and placebo groups, respectively.[3] Change from baseline (CFB) in serum TTR levels remained unchanged at Month 30 in the placebo-only group (mean [SD] = –0.4 [4.92] mg/dL). Characteristics of pts analysed are described in Fig. 1. A total of 380/611 pts (62.2%) entered the OLE study (229 pts continued acoramidis only, and 23 switched from placebo+tafamidis to acoramidis). At the time of data cutoff, 214 pts who had received acoramidis only completed Month 6 in OLE versus 18 who switched from placebo+tafamidis to acoramidis. At Month 30 in ATTRibute-CM, CFB in serum TTR levels were higher for patients who received acoramidis only than those receiving placebo+tafamidis (Fig 2A). Serum TTR levels increased further in pts who switched from placebo+tafamidis to acoramidis in OLE (Fig. 2B). The OLE study is ongoing, and this analysis includes pts who completed the Month 6 visit at time of data-cut. Conclusion(s) CFB in serum TTR levels were higher in pts receiving acoramidis only than those receiving placebo+tafamidis at Month 30 in the double-blind study. A further significant increase in serum TTR levels was observed in those who received placebo+tafamidis and switched to acoramidis in OLE.

Abstract Background Autonomously functioning thyroid nodules (AFTNs) constitute 5% to 7% of thyroid nodules and represent the second most common cause of hyperthyroidism following Graves’ disease. Currently, radioactive iodine (RAI) and surgery are the standard treatment options, and both incur a risk of postprocedural hypothyroidism and other surgery and radiation-related complications. Methods This work aimed at assessing the efficacy of radiofrequency ablation (RFA) as an alternative treatment option for resolving hyperthyroidism and the nodule volume rate reduction (VRR) and its associated adverse events. Results A total of 22 patients underwent RFA for a solitary AFTN. Seventy-two percent (n = 16) had subclinical hyperthyroidism, 9% (n = 2) had overt hyperthyroidism, and 18% (n = 4) were biochemically euthyroid on antithyroid medication. Average pretreatment TSH was 0.41 mIU/L (SD = 0.98) and free T4 1.29 ng/dL (SD = 0.33). Following a single RFA session, hyperthyroidism resolved in 90.9% (n = 20) and average VRR (61.13%) was achieved within 3 to 6 months following the ablation. Except for 1 nodule, none of the nodules grew during the follow-up period (16.5 months). Two patients (9%) developed transient tachycardia requiring short-term beta-blocker therapy, and 2 developed mild hypothyroidism requiring levothyroxine therapy. Two patients developed recurrent hyperthyroidism and elected to undergo lobectomy and repeat RFA respectively. No serious adverse effects were noted in this cohort. Conclusion RAI and/or surgery represent the standard of care for toxic adenomas, but RFA shows excellent efficacy and safety profile. Therefore, at centers with RFA expertise, it should be considered an alternative treatment strategy, avoiding radiation and surgery-related complications.

Abstract Background and study aims Use of fluoroscopy in gastrointestinal endoscopy is an essential aid in advanced endoscopic interventions. However, it also raises concerns about radiation exposure. This study aimed to develop consensus-based statements for safe and effective use of fluoroscopy in gastrointestinal endoscopy, prioritizing the safety and well-being of healthcare workers and patients. Methods A modified Delphi approach was employed to achieve consensus over three rounds of surveys. Proposed statements were generated in Round 1. In the second round, panelists rated potential statements on a 5-point scale, with consensus defined as ≥80% agreement. Statements were subsequently prioritized in Round 3, using a 1 (lowest priority) to 10 (highest priority) scale. Results Forty-six experts participated, consisting of 34 therapeutic endoscopists and 12 endoscopy nurses from six continents, with an overall 45.6% female representation (n = 21). Forty-three item statements were generated in the first round. Of these, 31 statements achieved consensus after the second round. These statements were categorized into General Considerations (n = 6), Education (n = 10), Pregnancy (n = 4), Family Planning (n = 2), Patient Safety (n = 4), and Staff Safety (n = 5). In the third round, accepted statements received mean priority scores ranging from 7.28 to 9.36, with 87.2% of statements rated as very high priority (mean score ≥ 9). Conclusions This study presents consensus-based statements for safe and effective use of fluoroscopy in gastrointestinal endoscopy, addressing the well-being of healthcare workers and patients. These consensus-based statements aim to mitigate risks associated with radiation exposure while maintaining benefits of fluoroscopy, ultimately promoting a culture of safety in healthcare settings.

Abstract Disclosure: O. Hamidi: Advisory Board Member; Self; Corcept, Neurocrine Biosciences, Amryt Pharma, Recordati Rare Diseases, Lantheus, Xeris. B.H. Salama: None. P. Dogra: None. A.P. Dackiw: None. F. Nwariaku: None. A. Islam: None. A. Mehta: None. S.C. Oltmann: None. S. Mirfakhraee: None. T. McKenzie: None. T.R. Foster: None. M. Lyden: None. B.M. Dy: None. I. Bancos: None. Introduction: Patients with mild autonomous cortisol secretion (MACS) are at risk for adrenal insufficiency (AI) after unilateral adrenalectomy. We aimed to determine the prevalence, predictors, and duration of AI after unilateral adrenalectomy for MACS, and to compare baseline and peak cortisol post cosyntropin stimulation test (CST) in diagnosing AI. Methods: We conducted a dual-center retrospective cohort study of patients with MACS who underwent unilateral adrenalectomy and were evaluated with postoperative cosyntropin stimulation test (CST). AI was diagnosed when postoperative morning cortisol was <10μg/dL and/or CST peak cortisol was <18μg/dL. Baseline and CST peak cortisol levels were considered concordant when both met corresponding cut-offs. Biochemical (BSS) and clinical (CSS) severity scores for hypercortisolism were calculated. Results: In 100 adults with MACS (77% women, median age 56 years, interquartile range [IQR] 48-63), median adenoma size was 2.8 cm (IQR, 2.2-3.7), and 25 (25%) had bilateral nodules. Median BSS was 3 (IQR, 2-5) and median CSS was 4 (IQR, 2-8). After adrenalectomy, AI was diagnosed in 56 (56%) patients. AI was associated with higher BSS, larger tumor size, but not age, sex, BMI, tumor laterality. Baseline and CST peak cortisol levels were concordant in 76% of cases. In 14% of cases morning cortisol was <10μg/dL but CST peak cortisol was ≥18μg/dL, and in 10% of cases morning cortisol was ≥10μg/dL, but CST peak cortisol was <18μg/dL. On a multivariable analysis that included age, sex, BMI, BSS, laterality, and tumor size, only higher BSS (odd ratio [OR] = 1.6 per 1 point) was associated with postoperative baseline cortisol <10μg/dL (P<0.05 for all). Independent predictors of CST peak cortisol <18μg/dL were BSS (OR 1.5 per 1 point) and unilateral adenoma (OR 3.7). During a median postoperative follow up of 13 months, 33 (59%) patients recovered from AI. Median time to recovery was 6.0 months, with AI recovery in 28% of patients by 2 months, 42% by 3 months, 53% by 6 months, and 64% by 12 months. Conclusions: Prevalence of postoperative AI in MACS was 56%. Only 76% of patients had concordant baseline and CST peak cortisol, with peak CST cortisol being more commonly abnormal in patients treated for unilateral MACS. Patients with larger adenomas and higher BSS were at higher risk for AI. Patients with MACS should be counseled about the risk and duration of AI after adrenalectomy. Presentation: 6/3/2024

4591 Background: EV-302 and CheckMate 901 demonstrated significant survival benefit with enfortumab vedotin-pembrolizumab (EVPembro) and gemcitabine-cisplatin-nivolumab (GemCisNivo) as 1L therapy, respectively, in patients (pts) with la/mUC. However, whether these treatments are cost-effective or not remains unclear. Methods: A three-state Markov model (progression-free, progression and death) was developed. State utilities were derived from published literature. State transition probabilities were informed from point-probabilities and hazard ratios for OS and PFS obtained from the latest follow-up of eligible trials. Average sales price (2024 USD) for individual treatments (excluding ancillary charges) were obtained from the center of medicare and medicaid services (US payer’s perspective). Treatment strategies were modeled in accordance with the dose/schedule reported in the eligible trials. Pts who received GemCis or Gem-carboplatin (GemCarbo) and did not progress were modeled to receive Avelumab maintenance. Half-cycle corrected costs and utilities were accrued over a 10-year lifetime horizon and were discounted at 3%. Monte Carlo simulation was used to estimate quality adjusted life years (QALYs) and incremental cost-effectiveness ratios (ICERs). A willingness-to-pay threshold (WTP) of 100,000$ per QALY was used. Results: In cisplatin-eligible pts, GemCisNivo demonstrated a 0.8 QALY gain over GemCis at an ICER of 21,127 ($/QALY). GemCisNivo was also associated with an incremental net monetary benefit (INMB) of 63,099$ relative to GemCis. EVPembro demonstrated a 2.4 QALY gain over GemCis at an ICER of 915,283 and a 1.6 QALY gain over GemCisNivo at an ICER of 1,406,308. In cisplatin-ineligible pts, EVPembro demonstrated a 2.4 QALY gain over Gem-carboplatin (GemCarbo) at an ICER of 934,761. Price threshold analyses demonstrated that EVPembro is likely to be cost-effective at a cost of 12,344$ for cisplatin-eligible and 13,374$ per cycle for cisplatin-ineligible pts (original cost: 35,665.60$ per cycle). Sensitivity analysis using a total of 12 cycles for EVPembro showed cost-effectiveness at an ICER of 69,594 relative to GemCisNivo in cisplatin-eligible pts, and at an ICER of 53,099 relative to GemCarbo in cisplatin-ineligible pts. Conclusions: In terms of US payer’s perspective, GemCisNivo is most likely to be cost-effective in cisplatin-eligible pts at the WTP of 100,000 $/QALY. Limiting the number of cycles for EVPembro may render it as a cost-effective 1L treatment in la/mUC pts regardless of cisplatin-eligibility status.