P2837Day-case complex left atrial ablation is safe and cost-effective: experience from a UK tertiary centre

Background

Day-case standard catheter ablation is becoming routine. However, patients having complex left atrial ablation for atrial fibrillation (AF) or left atrial tachycardia (LAT) often stay overnight. We have been performing day-case complex left atrial ablation since 2015.

Purpose

To evaluate the safety, efficacy and cost-effectiveness of day-case complex left atrial ablation compared with those who stayed overnight.

Methods

A retrospective analysis of all consecutive complex left atrial ablations performed in a UK tertiary cardiac centre between 2010–2018. Data were collected on baseline parameters, procedure details including mapping technique, ablation strategy, immediate efficacy, and acute complications.

Results

A total of 830 complex left atrial catheter ablations were performed; mean age±SD=60±12 years, 63% male. The majority were AF ablation (n=804, 96.9%), with the rest being LAT/left-atrial flutter. Of the AF cases, 545 were paroxysmal (≤7 days), 212 persistent (>7 days) and 47 long-standing (>1yr); 98% of cases were elective. Pulmonary vein isolation was performed in all; additional LA lines were done in 163, CTI ablation in 129 and CFAEs in 33. 3D-mapping (Carto/Precision)=44.7% (with contact sensing=38.0%), PVAC=18.7%, PVI cryo-balloon=36.6%. Of the cohort 331 (39.9%) were done as day-case. Acute success= 94.9%, acute complications=4.58% (femoral site complications, n=12; pericardial effusion, n=19 (9 needing drain); stroke/cerebral embolus, n=3; phrenic nerve palsy, n=5; first degree heart block, n=1). Comparison of day-case vs non day-case revealed no significant difference in number of complications (Table 1). An overnight stay at out hospital costs £350. During the period of study our institution saved £115.850 (∼140,000 euros).

Day-case vs non day-case ablation Parameters Day-case (n=331) Non day-case (n=499) p-value Mean age ± SD (years) 61.2±11.6 59.1±11.9 0.009 Males (n, %) 205 (61.9%) 321 (64.3%) 0.484 Normal heart (n, %) 243 (73.4%) 383 (76.8%) 0.276 Paroxysmal AF (n, %) 218 (65.9%) 327 (65.5%) 0.928 Fluoroscopy time (mins) 23.8±13.9 27.0±14.5 0.001 Procedure time (mins) 150±89.6 163±68.2 0.025 % with 3D-mapping 30.8% 56.9% <0.001 Acute complications (n, %) 12 (3.63%) 26 (5.21%) 0.285

Conclusions

Day-case complex left atrial cardiac ablation is safe and effective. It is associated with good clinical outcomes and leads to significant cost savings as an overnight stay is not needed.

P10: IBRUTINIB ASSOCIATED AUTOIMMUNE HEMOLYTIC ANEMIA

Purpose of Study

Autoimmune hemolytic anemia (AIHA) is a common phenomenon in Chronic lymphocytic Leukemia (CLL)/Small Lymphocytic Lymphoma (SLL) accounting for about 4–7% of cases. AIHA is commonly associated with certain conventional chemotherapy agents used in CLL/SLL. Ibrutinib, bruton tyrosine kinase inhibitor is category 1 indication for high risk (del 17p) and relapsed/refractory CLL. Literature review reports 11cases of Ibrutinib associated AIHA.

We report a case of AIHA precipitated by Ibrutinib in an high risk CLL patient, with prior history of AIHA.

Methods Used

Patient is an 81 year old black man diagnosed with asymptomatic Stage I CLL (del 17p) in 2010 and was on active surveillance. He developed AIHA in 2012, with good response to steroids and Rituximab. Subsequently he received 8 cycles of rituximab for symptomatic CLL with resolution of symptoms. In 9/2014, noted to have progression of disease with worsening B symptoms, leukocytosis and lymphadenopathy. He was started on Ibrutinib 420 mg PO daily with regression of lymphadenopathy within 3 weeks of therapy, but presented with symptomatic anemia with hemoglobin of 3 gm/dl, positive direct Coomb's test, elevated reticulocyte count and LDH consistent with AIHA. WBC elevated at 360 K/uL from baseline of 150 K/uL and hemoglobin fell to 3 g/dl from 10 g/dl since Ibrutinib was initiated. Ibrutinib was held and patient received high dose prednisone followed by IVIG and cautious transfusion with minimal improvement in hemoglobin. Hemoglobin slowly up trended with weekly Rituximab and high dose steroids and remained stable around 10 gm/dl after 4 weeks of Rituximab. Ibrutinib was subsequently restarted with overall clinical improvement.

Summary of Results

In our patient, occurrence of AIHA falls in between 2–4 weeks as other reported cases suggesting that Ibrutinib could be a likely precipitating factor.

Conclusions

Review of data, reveals that 22% of patients had history of AIC prior to Ibrutinib, however occurrence of AIHA on Ibrutinib seems to be less common (0.7%).Mechanism of action of Ibrutinib associated cytopenias remains unclear. It was hypothesized that it may be due to IL-2 induced kinase inhibition by Ibrutinib, and needs further investigation.

P18: MULTIPLE DIAGNOSIS OR CONTINUUM OF DISEASE: MULTICENTRIC CASTLEMAN'S DISEASE

Purpose of Study

Multicentric Castleman's disease (MCD) is a rare lymphoproliferative disorder characterized by peripheral lymphadenopathy (LAD), hepatosplenomegaly(HSM), and B symptoms. It is associated with HIV and HHV8 infection.

We report a case of young woman presented with B symptoms, workup suggestive of lupus but lymph node biopsy (BX) was consistent with MCD. Association of SLE with MCD is rare. We report this case to increase awareness of this potential diagnostic and therapeutic dilemma.

Methods Used

Patient is a 27 yr old black woman presented with malaise, fevers, cough, weight loss, arthralgia, alopecia, numbness of extremities and Raynaud's phenomenon. Patient had skin tightness around the mouth, telangiectasia, digital ulcers, HSM, pitting edema, diffuse LAD and moderate pericardial effusion.

Laboratory results consistent with hemolytic anemia with Hb 5.6 g/dl, direct coombs positive, elevated reticulocyte count, LDH and low haptoglobin. Initial RF, ANA, and all infectious work up including HIV were normal. She was transfused cautiously, with inconclusive LN and bone marrow Bx. Patient left hospital against medical advice.

She presented two days later with altered mental status (AMS) and hypotension. CT head and Lumbar puncture were negative. Hypotension responded to fluids, but no response in AMS. Repeat ANA, AntiSSB, AntiSm, AntiRNP, and Antihistone antibodies were positive. Patient met diagnostic criteria for SLE and was subsequently treated for lupus cerebritis with pulse steroids, with moderate improvement in mental status. Repeat LNBX revealed reactive lymphadenitis with features of MCD, HHV8 negative. Patient was treated with IL-6 inhibitor Siltuximab, with significant improvement in mental status.

Summary of Results

MCD is a rare angiolymphoproliferative disorder of unclear etiology. Most cases occur in middle aged men and are associated with immunosuppression where as SLE is common in women of child bearing age. Reported cases of MCD in association with SLE are common in immunocompetent young women. Our patient is a young woman, HIV/HHV8 negative with good response to Siltuximab, favoring MCD.

Conclusions

It is unclear whether this finding of MCD and SLE represents an overlap or a pure association. However, this phenomenon needs further investigation.

P4: CIRCULATING MIRNA PROFILES POINT TO DYSREGULATION IN TGFBETA/SMAD3 TUMOR SUPPRESSOR SIGNATURE IN BRCA POSITIVE BREAST CANCER PATIENTS

Purpose of Study

Over 240,000 individuals are diagnosed with breast cancer (BrCa) of which 12,000 individuals carry BRCA germline mutations. MicroRNA dysregulation is common in malignancy and may correlate with germline mutations.

Aims:

1. Analyze microRNAs in patients with breast cancer with or without BRCA germ line mutations, with and without cancer.

2. Identify molecular BRCA mutant patients to deduct reasons for accelerated malignancy.

Methods Used

We analyzed plasma miR expression from 94 br cancer patients (41 BRCA positive) relative to 24 normal controls. All samples were collected between 2010 and 2014 and survival data was known for all cancer patients. TaqMan Open Array panel was used to simultaneously run hundreds of microRNA assays in the Applied Biosystem Open array real time PCR. Using AB open array real time PCR, 756 miRNA species were detected. Two-sample t-test was used for all 2-sample comparison and ANOVA followed by Tukey HSD post-hoc test to compare the miRs mean differences. All tests were 2-tailed and results with a p<0.05 were considered statistically significant.

Summary of Results

BRCA+underexpressed hsa-mir-10a and hsa-mir-376c and over-expressed Hsa- mir- 326 and Hsa-mir-143 relative to BRCA-; p<0.05.

Using Coremine data mining linking genes and diseases differentially expressed circulating miRs are linked to tumor suppressor TGFbeta/SMAD3.

Conclusions

The early onset of breast cancer in BRCA mutant patients may recapitulate the pro-oncogenic effects of TGF-β. The context dependent SMAD3 binding & tumor suppression TGF-β effects are abrogated in BRCA mutant patients. TGF-β/Smad3 tumor-suppressor signature suppresses local inflammation in the tumor microenvironment.