Diagnostic Catheterization Research Articles

CTEPH: A Kaiser Permanente Northern California Experience

IntroductionChronic thromboembolic pulmonary hypertension (CTEPH) is a rare and life-threatening form of pulmonary hypertension and the only potentially curable form of the World Health Organization Pulmonary Hypertension classes. Thus, the prompt and accurate diagnosis of this condition is imperative. Despite widespread chronic symptoms following acute pulmonary embolism (PE), the condition is rarely considered, and an externally validated inexpensive diagnostic algorithm is lacking. MethodsA long-term, retrospective cohort study was conducted to assess the incidence of CTEPH following acute PE in a real-world study population. Additional data were collected regarding the practice patterns of diagnostic testing and imaging, particularly in patients with persistent or recurrent symptoms. Amongst diagnosed CTEPH patients, previously established risk factors were evaluated for degree of risk and commonly used diagnostic tests (electrocardiogram [ECG] right ventricular hypertrophy [RVH] pattern, B-type natriuretic peptide [BNP] elevations) employed during this period were evaluated and assessed for feasibility as screening tests. The study population was obtained from the MAPLE study cohort, comprised of patients presenting with acute PE in 21 community medical centers across the Kaiser Permanente Northern California system from January 2013 to April 2015. Diagnosis of CTEPH was confirmed via pulmonary vascular imaging (ventilation/perfusion [V/Q] scanning, computed tomography angiography, pulmonary angiography) and diagnostic right heart catheterization (RHC). Probable diagnoses were defined as a combination of suggestive echocardiographic and RHC findings. Additional inclusion criteria included age (≥18 years) with at least 2 years follow up and no previous diagnosis of CTEPH or PE during the prior 30 days. ResultsThere were 1973 patients who met inclusion criteria (mean age 62.4 years). Despite 75 % of patients developing symptoms consistent with CTEPH >3 months following acute PE, only 5.6 % of these symptomatic patients underwent V/Q scanning. There was overall a very low cumulative incidence of CTEPH (2.3 %), which was significantly higher amongst patients with symptoms compared to those without symptoms. When controlled for confounding in the multivariate analysis, only recurrent PE (HR 19.3, P < 0.001) and pulmonary artery systolic pressure >50 mmHg (HR 10.4, P < 0.001) were statistically significant predictors of CTEPH. Of the non-invasive diagnostic tests, ECG criteria for RVH were found to be poorly sensitive (2.6 %), but very specific (98.8 %) for CTEPH. Elevated levels of BNP alone were more sensitive than RVH ECG criteria (76.3 %) but poorly specific (44.4 %). ConclusionsThe diagnosis of CTEPH is uncommonly made following acute PE. Despite the frequency of persistent symptoms consistent with CTEPH following acute PE, the appropriate diagnostic work-up is rarely undertaken as evidenced in this cohort. This suggests that CTEPH is underappreciated and rarely considered, likely underestimating the true incidence in this cohort. Future studies are needed to elucidate the true prevalence of CTEPH and further investigate both the optimal diagnostic tools and timing of appropriate screening. These discoveries may help guide future development of diagnostic algorithms that can effectively rule out and accurately identify this potentially curable disease in a timely manner.

112 A CASE OF INCESSANT SLOW-FAST AVNRT TREATED WITH HIS BUNDLE PACING

Abstract Introduction Slow-fast AVNRT can rarely present as incessant SVT, particularly in patients with increased HV interval. We describe a case of incessant typical AVNRT, treated without transcatheter ablation. Case Presentation An 83-year-old man, with history of PAF, was admitted to our ICU complaining of dyspnea, dizziness and amaurosis. His ECG at presentation depicted sinus bradycardia, first degree AVB (PQ=400 ms) and RBBB (Fig 1A). After betablocker wash-out period, we decided to perform CSP using HBP to ensure AV synchrony and restore physiological pacing. During wash-out period, an incessant regular wide complex tachycardia with RBBB morphology and ventricular rate of 110 bpm occurred: the tracing showed a P wave immediately after the QRS, with RP &amp;lt; PR (Fig 1B). The tachycardia was incessant also in the EP lab. By means of 2 pacing leads (RV lead in the apical septum and RA lead in right appendage) and one diagnostic decapolar catheter (Inquiry, 2-2-2 Abbott) in His region, all connected to the polygraph, we performed an EPS. HV interval in sinus rhythm was 60 ms, AH 340 ms. The electrograms during tachycardia showed HVA sequence and 1:1 VA association, VA&amp;lt; 70 ms, cycle length 520 ms. Pacing from RV lead, we performed the ventricular overdrive pacing maneuver obtaining a VAV response; PPI-TCL was 280 ms and SA-VA difference was 205 ms (Fig 2A). We also noted a VA linking response to atrial overdrive pacing, and AHA response at the end of maneuver excluding JT (Fig 2B). In addition, pacing by the His catheter during tachycardia, we interrupted the arrythmia: the V signal after the last paced beat was not followed by retro-conducted A signal (Fig 2C). Finally, by administrating adenosine 12 mg the tachycardia interrupted with A as last signal recorded (Fig 2D). All these findings were consistent with an incessant typical AVNRT. We chose to treat AVRNT with sequential atrial-His pacing, placing a third lead in His region and programming the device in DDD 70-120, with selective His bundle capture, not correcting the RBBB (Fig 1C, D). Discussion In patients with poor anterograde AV nodal conduction, also slow-fast AVNRT can present as incessant tachycardia. In fact, a shorter sinus cycle length or atrial extrasystole could initiate sufficient delay in anterograde conduction to allow for recovery in conduction in the retrograde direction led to a persistent tachycardia. This case highlights the value of performing EPS diagnostic maneuvers also during PM implantations in order to personalize therapy and programming.

Early Postoperative Congenital Cardiac Catheterization Outcomes: A Multicenter Study

BackgroundEarly postoperative catheterizations (EPOCs) within 6 weeks after a congenital heart surgical procedure can treat residual lesions and provide important clinical information. However, EPOCs are often assumed to impose additional risk on a vulnerable patient population. This study aimed to describe the EPOC population, evaluate procedural safety, compare EPOC patients with procedure-matched non-EPOC patients, and determine risk factors for poor outcomes using data from the Congenital Cardiac Catheterization Project on Outcomes registry. MethodsIn a retrospective cohort, demographic, clinical, and procedural characteristics were analyzed for diagnostic and interventional catheterizations performed in 13 participating institutions from January 2014 to December 2017, excluding patients after heart transplant. The primary outcome was a high-severity adverse event (AE). Three distinct analyses included (1) describing the full cohort and EPOC patients, (2) comparing EPOC patients with and without a high-severity AE, and (3) comparing EPOC patients with controls matched on case type. ResultsThis study included 17,776 catheterizations, with 1399 EPOCs. The high-severity AE rate was 6.4% overall, 8.9% in the EPOC cohort, and 8.4% in matched controls (P = .74). The association between EPOC status and high-severity AE was not significant in a multivariable model (P = .17). In EPOCs with a high-severity AE, median procedure duration was 30 minutes longer (P < .001), and median time from surgical procedure to catheterization was 3 days longer (P = .05). ConclusionsEPOC was not associated with additional risk. Individual patient characteristics of size and hemodynamic vulnerability may serve as informative predictors. Timely catheterization may preempt further clinical deterioration, and intraprocedure duration optimization may correlate with improved outcomes.

Left Heart Disease Phenotype in Elderly Patients with Pulmonary Arterial Hypertension: Insights from the Italian PATRIARCA Registry.

Pulmonary arterial hypertension (PAH) in the elderly is often associated with left heart disease (LHD), prompting concerns about the use of pulmonary vasodilators. The PATRIARCA registry enrolled ≥70 year-old PAH or chronic thromboembolic pulmonary hypertension (CTEPH) patients at 11 Italian centers from 1 December 2019 through 15 September 2022. After excluding those with CTEPH, post-capillary PH at the diagnostic right heart catheterization (RHC), and/or incomplete data, 23 (33%) of a total of 69 subjects met the criteria proposed in the AMBITION trial to suspect LHD. Diabetes [9 (39%) vs. 6 (13%), p = 0.01] and chronic kidney disease [14 (61%) vs. 12 (26%), p = 0.003] were more common, and the last RHC pulmonary artery wedge pressure [14 ± 5 vs. 10 ± 3 mmHg, p < 0.001] was higher and pulmonary vascular resistance [5.56 ± 3.31 vs. 8.30 ± 4.80, p = 0.02] was lower in LHD than non-LHD patients. However, PAH therapy was similar, with 13 (57%) and 23 (50%) subjects, respectively, taking two oral drugs. PAH medication patterns remained comparable between LHD and non-LHD patients also when the former [37, 54%] were identified by atrial fibrillation and echocardiographic features of LHD, in addition to the AMBITION criteria. In this real-world snapshot, elderly PAH patients were treated with pulmonary vasodilators, including combinations, despite a remarkable prevalence of a LHD phenotype.

Local diagnostic reference levels in diagnostic and therapeutic pediatric cardiology at a specialist pediatric hospital in South Africa

Abstract Introduction: Children may be at a higher risk of experiencing the detrimental effects of ionizing radiation arising from medical radiation imaging. Dose optimisation is therefore recommended to provide assurance that their exposure is as low as reasonably achievable. To this end, periodic assessment of dose levels and establishment of Local Diagnostic Reference Levels (LDRLs) in medical facilities is necessary. There is a general paucity in the literature of data pertaining to dose levels in pediatric interventional radiology. This study establishes LDRLs in diagnostic and therapeutic heart catheterization procedures at a specialist pediatric hospital in a resource constrained country. Material and methods: Dose indicators from actual patient procedures were collected from the archive and analyzed retrospectively to determine the median, 25th, and 75th percentiles of the total Air Kerma Area Product (KAP), Cumulative Air Kerma (CAK), total Fluoroscopy Time (FT), and a total number of Cine Images (CI) of selected interventional procedures. The dose indicators were also age-stratified into five age groups defined by the International Commission on Radiation Protection publication 135. The results were compared to values available from similar studies in the literature to benchmark our dose levels. Local Dose Reference Levels were set as the 75th percentile values. Results: For diagnostic procedures (n = 80), the 75th percentiles of KAP, CAK, FT, and CI were 4.0 Gy·cm2, 31.5 mGy, 14.3 min, and 315 frames, respectively and 3.2 Gy·cm2, 30.5 mGy, 17.5 min, and 606 frames, respectively for therapeutic procedures (n = 143). Conclusions: The LDRLs from this study did not vary significantly from those published in the literature, suggesting that practices at our center were comparable to international norms. Regular reviews of the LDRLs must be conducted to check that the dose levels do not deviate considerably.

Abstract 14633: A Case of Acute Coronary Syndrome With Incidental Acquired Factor VIII Deficiency With Inhibitor Present: How to Navigate Being Between a “Rock” and a Bleeding Disorder

Introduction: Acute coronary syndrome (ACS) occurring in the presence of a bleeding diathesis can make clinical decision-making difficult. We present a case of a non-ST elevation MI in the presence of an acquired factor VIII deficiency with an inhibitor present. Case: A 66-year-old male with a medical history significant for coronary artery disease and COPD presented with a 4-day history of persistent, profuse bleeding after attaining a laceration on his arm. Shortly after admission, he reported pressure-like chest pain relieved by sublingual nitroglycerin. His 5th generation troponin level was 61 ng/L on presentation and peaked at 600 ng/L 36 hours later. The EKG revealed ST depressions in leads V3 and V4 and T-wave flattening in leads V5 and V6. Transthoracic echocardiography revealed preserved ejection fraction but could not exclude wall motion abnormalities due to poor windows. Hematology was consulted due to uncontrolled bleeding, and the patient was diagnosed with acquired factor VIII deficiency with an inhibitor present. Low-dose heparin infusion was initiated. He was taken for a diagnostic left heart catheterization, which revealed left main with moderate obstruction, left anterior descending (LAD) with 70% proximal stenosis, and a small diagonal branch with 90% stenosis. The patient had been previously offered evaluation for coronary artery bypass graft(CABG) surgery but declined. CABG work up was ultimately deferred in favor of percutaneous coronary intervention based on literature review extrapolated from hemophiliac patients. The patient’s hematologic care is ongoing with recombinant antihemophilic factor, porcine sequence, prednisone, cyclophosphamide, and rituximab administration. Discussion: Choosing the type of coronary revascularization in coagulopathic patients poses a significant challenge. To avoid complications, a multidisciplinary approach to short- and long-term anticoagulation management is necessary. In this case we decided to use existing data that is based on hemophilia patients in the past with myocardial infarction where dual antiplatelet therapy is limited to 1 month with factor 8 activity maintained above 30%. Then transition to aspirin alone for maintenance with factor 8 levels maintained above 10%.

Abstract 15535: A Case of Suspected Menstruation Induced QTc Prolongation Leading to Torsades De Pointes

Estrogen is known to produce changes in cardiac electrophysiology specifically in premenopausal women, increasing the risk of arrhythmias. We report a case of Torsades de Pointes (TdP) in a young premenopausal female. A 25-year-old female with a history of anxiety presented to the emergency room (ED) with several days of vomiting. While in the ED, she had an unwitnessed syncopal event, and was found to be in pulseless ventricular fibrillation (V-Fib) . She required one defibrillation to obtain return of spontaneous circulation (ROSC). Initial work up showed calcium 7.6 mg/dl, phosphorous 1.1 mg/dl, magnesium 2.4 mg/dl, potassium 4.0 mg/dl. Remainder of electrolytes were normal. Toxicology screen was positive for cannabinoids. Post ROSC EKG showed sinus tachycardia at a rate of 103bpm with a prolonged QTc of 531ms. Patient was not on any medications outpatient. On further discussion, patient reported no prior history of syncopal episodes, palpitations, and denied any family history of sudden cardiac death. She did report she was presently on her menses. Shortly after admission, she had recurrent polymorphic ventricular tachycardia which degenerated to TdP. She was loaded with magnesium. Echocardiogram showed an ejection fraction (EF) of 35-39% and global hypokinesis. Diagnostic left heart catheterization was performed revealing clean coronaries. Cardiac MRI revealed EF of 43% without any late gadolinium enhancement. Her QTc remained prolonged even with electrolyte normalization. She underwent successful ICD placement and remained event free during the remainder of the hospital course. She will undergo genetic work up for long QT syndrome. Female sex hormones, specifically estrogen, have been described in literature as pro-arrhythmic given its effects on QT prolongation and ion gated channels. Prior cases of menstruation dependent arrhythmias have speculated that the abrupt reduction in estradiol prior to menstruation is associated with increased cyclic adenosine monophosphate dependent arrhythmogenicity. This case highlights the multifactorial etiology of sudden V-Fib arrest in a young female, and the importance of understanding the role that sex hormones play in the underlying pathogenesis.

Abstract 10266: T-Wave Features Predict Functional Worsening in Children With Pulmonary Arterial Hypertension: Machine Learning Insights From Standard ECG

Introduction: Various T-wave characteristics have been shown to be predictive of ventricular diastolic dysfunction and sudden cardiac death in adults. However, specific T-wave morphologies and their predictive potential in pediatric patients is unknown. Hypothesis: Machine learning derived T-wave characteristics will be different between children with pulmonary arterial hypertension (PAH) and healthy controls. Furthermore, T-wave characteristics will be predictive of clinical functional worsening in PAH patients. Methods: Principal component analysis (PCA) was applied to ECGs collected for children with PAH (n=155) at the time of diagnostic catheterization and matched healthy controls (n=47) to describe basic T-wave characteristics. Patients (&lt;18 y/o) with PAH were defined as a mean pulmonary pressure &gt;25 mmHg in the absence of obstructive left heart disease. Interpreted T-wave features were then compared between PAH and control groups. Identified T-wave measurements underwent survival analysis using standardized PAH functional class worsening as a clinical endpoint. Results: Identified T-wave principal components were 1) T-wave height and 2) early or late incidence of T-wave peak (FIGURE- 1A). The second principal component was associated with PAH diagnostic specificity (94%). Time from T-wave peak to T-wave end (TpTe) as measured in leads V4 to V6 was significantly higher in children with PAH (all P &lt; 0.001) (FIGURE - 1B). V4 derived TpTe value &gt; 132 ms and V5 derived TpTe value &gt; 135 ms were associated with the higher probability of clinical functional worsening (P = 0.018 and P = 0.002, respectively) (FIGURE - 1C). Conclusions: T-wave features derived from standard ECG are 1) different between children with PAH and their healthy peers and 2) predictive of clinical functional worsening.

Abstract 14711: Radial Artery Patency Following Distal Transradial Access in Patients With Advanced Chronic Kidney Disease

Background Radial artery occlusion (RAO) with transradial access is reported in 6-9% of patients with advanced chronic kidney disease (CKD) and may preclude the creation of an arteriovenous fistula for dialysis. Distal transradial access (dTRA) has lower rates of RAO compared with proximal transradial access but studies excluded patients with advanced CKD. Methods: We sought to define procedure characteristics and RAO rates with dTRA in CKD. Patients who underwent cardiac catheterization with dTRA from 01/01/2019 to 01/01/2022 with follow-up of radial artery patency by reverse Barbeau or repeat access of the artery were included. Results: A total of 68 patients with a median age of 60 (IQR 54-69), 50 (74%) males were included. A total of 44 (65%) were on hemodialysis. Of the procedures, 59 (87%) were diagnostic and 9 (13%) were PCIs. Access was ultrasound guided, a majority (79%) were right dTRA and all had spasmolytic therapy and patent hemostasis. Sheaths were 5 French short (7 cm) in 40 (59%) and 6 French short in 28 (41%). Mean contrast volume was 20+/-11 ml for diagnostic procedures and 91+/-53 ml for PCIs. Mean radiation exposure was 290+/-156 mGy for diagnostic procedures and 1692+/-961 mGy for PCIs. Mean fluoro time was 5+/-4 mins for diagnostic procedures and 24+/-13 mins for PCIs . Of 9 patients with PCIs, mean number of stents was 2+/-1 and atherectomy was used in 2 (22%) PCIs. The median number of diagnostic catheters was 1(IQR 1-2) and median guides was 1(IQR 1-1) in PCIs. Radial arteries were patent in 68 (100%) at follow-up. (Figure 1) Conclusions: Our cohort demonstrates safety of dTRA in patients with advanced CKD with high rates of radial artery patency.

Primary angioplasty using 6F diagnostic catheter in ST-elevation myocardial infarction

Primary angioplasty using 6F diagnostic catheter in ST-elevation myocardial infarction

Pediatrik Anjiolar: Tek Merkez Deneyimi

Objective: Congenital heart disease is the most common congenital anomaly. Early diagnosis and timely intervention are important in congenital heart disease. The aim of this study to share our experience and follow-up results of diagnostic and interventional angiography procedures performed in our center.&#x0D; Materials and Methods: The retrospective study included patients who underwent catheter angiography in our clinic between July 2018 and October 2021. &#x0D; Results: This study included 47 children with a mean age of 5.7 (SD, 2.9) years (0-17 years) who underwent catheter angiography. 47% of study population was girls. Diagnostic catheter angiography was performed in 29 patients. Successful interventional catheter angiography was performed in 18 patients. No significant complications were observed during or after diagnostic and interventional catheter angiography.&#x0D; Conclusion: Diagnostic and interventional angiography procedures can be performed successfully in our clinic. In recent years, interventional angiography procedure has been preferred more because it shortens the hospital stay and does not create surgical scar tissue.

Factors Contributing to Successful Transvenous Retrograde Thoracic Duct Cannulation

PurposeTo identify key factors for successful transvenous retrograde cannulation (TVRC) of the thoracic duct. Materials and MethodsA total of 47 consecutive patients (62.1 ± 13.2 years; 32 men) who underwent attempted TVRC between July 2016 and July 2021 were included. Reasons for interventions were chylous leakage from the chest (n = 36), abdomen (n = 6), and other sites (n = 5). Patient age, sex, access vein (femoral vs brachial), anatomic classification (presence of dominant channel vs plexiform) of the terminal thoracic duct, and engagement of a diagnostic catheter into the jugulovenous junction were included in the analyses. Anatomic details were evaluated according to catheter-based high-pressure lymphangiography and conventional intranodal lymphangiography. The Firth bias-reduced penalized-likelihood logistic regression model was used to analyze prognostic factors. ResultsTVRC was successful in 33 of the 47 patients (70%). In univariate analysis, femoral access, diagnostic catheter engagement, and presence of dominant channel were significant positive prognostic factors (P <.05). In multivariate analysis, diagnostic catheter engagement and presence of dominant channel were significant prognostic factors (P <.05). Diagnostic catheter engagement showed the highest prognostic performance (accuracy = 0.872), followed by presence of a dominant channel. High-pressure catheter-based lymphangiographic findings showed better performance (accuracy, 0.844 vs 0.727) than intranodal lymphangiography to delineate the anatomy of the terminal thoracic duct. ConclusionsA secure selection of the jugulovenous junction and the presence of a dominant channel in the terminal portion of the thoracic duct were significant prognostic factors for successful TVRC.

Culprit vessel revascularization first with primary use of a dedicated transradial guiding catheter to reduce door to balloon time in primary percutaneous coronary intervention.

The effect of a single transradial guiding catheter (STGC) for culprit vessel percutaneous coronary intervention (PCI) first on door-to-balloon (D2B) time remains unclear. Between February 2017 and July 2019, 560 patients with ST-elevation myocardial infarction (STEMI) were randomized into either the STGC group (n = 280) or the control group (n = 280) according to direct culprit vessel PCI with a STGC. In the STGC group, a dedicated transraidal guiding catheter (6F either MAC3.5 or JL3.5) was used for the treatment of electrocardiogram (ECG)-guided culprit vessel first and later contralateral angiography. In the control group, a universal diagnostic catheter (5F Tiger II) was used for complete coronary angiography, followed by guiding catheter selection for culprit vessel PCI. The primary endpoint was D2B time, and the secondary endpoint included catheterization laboratory door-to-balloon (C2B), procedural, fluoroscopy times, and major adverse cardiac events (MACE) at 30 days. The median D2B time was significantly shorter in the STGC group compared to the control group (53.9 vs. 58.4 min; p = 0.003). The C2B, procedural, and fluoroscopy times were also shorter in the STGC group (C2B: 17.3 vs. 24.5 min, p < 0.001; procedural: 45.2 vs. 49.0 min, p = 0.012; and fluoroscopy: 9.7 vs. 11.3 min, p = 0.025). More patients achieved the goal of D2B time within 90 min (93.9% vs. 87.1%, p = 0.006) and 60 min (61.4% vs. 51.1%, p = 0.013) in the STGC group. Radial artery perforation (RAP) was significantly reduced in the STGC group compared with the control group (0.7% vs. 3.2%, P = 0.033). MACE at 30 days was similar (2.5% vs. 4.6%, P = 0.172) between the two groups. ECG-guided immediate intervention on culprit vessel with a STGC can reduce D2B, C2B, procedural, and fluoroscopy times (ECG-guided Immediate Primary PCI for Culprit Vessel to Reduce Door to Device Time; NCT03272451).

Safety of intravenous cangrelor infusion during percutaneous coronary intervention in a real-world cohort of non-pretreated NSTEACS patients

Abstract Background and purpose Since publication of latest ESC guidelines in 2020, pretreatment with an oral P2Y12 receptor inhibitor (P2Y12i) is no longer systematically recommended in patients with non-ST elevation acute coronary syndrome (NSTEACS) [1]. Therefore, from now on, NSTEACS patients will arrive to the cathlab to a larger extent without having a loading dose of an oral P2Y12i administered. Cangrelor, a potent intravenous P2Y12i, is an emerging option that provides a rapid onset of platelet inhibition, but it has not been widely used yet [2]. We aimed to evaluate safety of cangrelor real-world use in NSTEACS patients who had not received an oral P2Y12i before percutaneous coronary intervention (PCI). Methods Development of periprocedural thrombotic complications, ischaemic and bleeding events at 30 days was retrospectively evaluated in a cohort of non-pretreated NSTEACS patients referred to PCI. Comparison among those who underwent intravenous infusion of cangrelor and those who received a loading dose of an oral P2Y12i (ticagrelor, prasugrel or clopidogrel) at the moment of PCI was performed. Results Between January and December of 2020, 155 non-pretreated NSTEACS patients were referred to our cathlab; of whom, 89 underwent PCI and were included in the analysis (18.0% with unstable angina, 82.0% with NSTEMI). Mean age was 66.0±14.3 years, 21 (23.6%) were female and the mean GRACE risk score was 112±34. PCI was performed ad-hoc (immediately after diagnostic catheterization) in 81 patients (91.0%), whereas 15 patients (16.9%) required PCI to be done in more than two times. Procedure was performed exclusively by radial or cubital artery access in 78 patients (87.6%). Regarding antiplatelet drug administration, cangrelor was used in 14 patients (15.7%), prasugrel in 35 (39.3%), ticagrelor in 29 (32.6%) and clopidogrel in 11 (12.4%). No significant differences were found among patients in terms of development of ischaemic events at 30 days (cardiovascular death, non-fatal myocardial infarction, non-fatal stroke or stent thrombosis) or periprocedural thrombotic events (no-reflow, bailout use of anti-IIb/IIIb or intraprocedural stent thrombosis). The use of cangrelor did not raise the incidence of bleeding events at 30 days (7.1% vs. 15.1%, p=0.682) [Table 1]. Cangrelor tended to be more frequently used in high-risk NSTEMI patients (20.8% vs. 12.9%, p=0.357) and in case of complex PCI (26.3% vs. 7.8%, p=0.018) [Figure 1]. After controlling by both variables, cangrelor did not significantly increase the risk of bleeding or ischaemic events at 30 days either. Conclusions Intravenous infusion of cangrelor during PCI in non-pretreated NSTEACS patients shows no differences in terms of thrombotic or bleeding events in comparison to the administration of a loading dose of an oral P2Y12i. Our results also suggest that cangrelor could be a safe option in patients with high thrombus burden who require complex PCI. Funding Acknowledgement Type of funding sources: None.

Atrio-ventricular nodal re-entrant tachycardia ablation step by step low fluoro approach to prevent unexpected AV block

Abstract Background Slow pathway (SP) radiofrequency (RF) ablation of AVNRT has a success rate of more than 98%, but up to 2% risk of unpredictable and frustrating AV node block despite the energy being delivered to the posterior aspect of Koch's Triangle (KT) which is far from the recorded His signal. A possible explanation is an atypical location of the AV node. KT pace-mapping (KTPM) has been demonstrated to be useful to recognize when AV is abnormally located in the mid or posteroseptal aspect of the KT. In these cases cryoablation would be the best choice because it is a well-established technique for the successful treatment of AVNRT with no complications reported but with a recurrence rate around 10% at long-term follow-up. Voltage bridge mapping (VBM) is a validated and effective technique in guiding cryoablation of AVNRT, with a complete acute success rate and no recurrences at mid-term follow-up. Aim To evaluate our low-fluoro step-by-step approach for AVNRT ablation including KTPM and VBM aiming to eliminate the risk of unpredictable AV node block. Methods The right atrium and coronary sinus electroanatomical mapping was done and diagnostic catheters were positioned at His and coronary sinus. After AVNRT diagnosis, 3D KTPM was performed. We developed it according to the “conventional” one in order to evaluate and visualize atypical AV node location during low-fluoro procedures. This was achieved by stimulating with the mapping catheter in the anteroseptal, posteroseptal and midseptal region respectively. Each point has been collected on 3D System measuring the interval between the stimulus to the His deflection (Fig. 1A–C). Voltage bridge-mapping was also performed, and both have been used as reference for SP RF ablation. If 3D KTPM showed a posterior extension of the AV node, then ablation was performed using cryo-energy aiming to reduce the risk of permanent AV node iatrogenic block. Methods and results 71 consecutive patients (mean age 61.0±14.5 SD, 46% female) undergoing low-fluoro ablation of AVNRT by 3D mapping system. KTPM was achieved in all the patients. In the 67 (94.3%) pts who showed superoparaseptal location of the AV node RF ablation was successfully performed. In 4 (5.7%) pts with midseptal extension of the AV node (Fig. 1D) a voltage-bridge mapping guided cryo-ablation was successfully performed (Fig. 1E). The mean procedural time was 95±18 SD min. Mean fluoro time was zero. After a mean follow-up of 28.5±16.7 SD moths, neither recurrences nor complications were recorded. Conclusion This is the first study to show how a tailored low-fluoro AVNRT SP ablation approach including 3D-PM of KT and VBM could be helpful to eliminate the risk of unpredictable and frustrating AV block. Our preliminary results would possibly encourage larger cohort, multicenter studies. Funding Acknowledgement Type of funding sources: None.

Catheter ablation of atrial arrhythmias by using a multipolar grid-patterned high density mapping catheter in patients with congenital heart disease: a single-center experience

Abstract Objective Catheter ablation of arrhythmias in patients with congenital heart disease (CHD) remains challenging and time-consuming. A novel diagnostic catheter with a multipolar grid-patterned electrode configuration for high density mapping may reduce mapping time and enhance ablation success. Here we describe our experience of catheter ablation by using a multipolar grid-patterned mapping catheter in patients with CHD suffered from atrial tachycardia. Methods All patients with CHD underwent catheter ablation for atrial tachycardia by using multipolar grid-patterned high density mapping catheter between 04/2018 and 12/2021 were enrolled. Primary success was defined as non-inducibility of atrial tachycardia. Only the first catheter ablation was included in the study. Results A total of 37 consecutive patients (median age 34.2±33.0 years (range 7–65), female n=20) underwent 37 ablation procedures with initial high density mapping. The underlying heart defects were s/p ASD-closure (n=2), ASD-closure and corrected partial anomalous pulmonary venous return (n=2), corrected unroofed coronary sinus (n=1), pulmonary valve commissurotomy (n=2), repaired Tetralogy of Fallot (n=2), tricuspid and pulmonary valve replacement in PA/IVS (n=1), mitral valve replacement (n=1), Hypoplastic right heart syndrome (n=1), atrial switch procedure for dTGA (n=7), TA with Glenn shunt (n=1), Ross operation (n=1), Fontan palliation (tricuspid atresia n=6, DILV n=5, HLHS n=1, DORV n=1, dTGA n=1, criss-cross heart n=1, single ventricle n=1). A history of previous ablation was positive in 8 patients. During mapping of the cardiac chambers, the mean value of total collected points and used points were 32657.8±46171 and 3851.6±3295.5 respectively. Mean mapping and fluoroscopy time were 62.1±40.7 minute (range 3–178) and 11.4±8.5 minutes (range 0–32.2), respectively. There were 69 atrial tachycardia substrates in the 37 patients (median 2, range 1–4 per patient). All tachycardia substrates were completely ablated in 33/37 (89.2%) patients and partially in 4/37 (11.8%) patients. Acute success was achieved with successful ablation of 65 of 69 (94.2%) atrial substrates. During a median follow-up time of 20 months (range 5–49), recurrence rate was 5/65 (7.7%) atrial substrates in 5/37 (13.5%) patients. Comparison of 16 patients with Fontan palliation to the 23 patients without Fontan operation showed higher partially success rate in the patients with Fontan palliation (4/16 vs. 0/21, p=0.028). Conclusion In this series, high density mapping allowed elucidation of the tachycardia mechanism in all patients with a high primary ablation success, a limited radiation exposure and a low rate of arrhythmia recurrence. Funding Acknowledgement Type of funding sources: None.

The prognostic value of vasoresponse to nitric oxide in patients with chronic thromboembolic pulmonary hypertension

Abstract Background Chronic thromboembolic pulmonary hypertension (CTEPH) is characterized by pulmonary artery obstructions due to organized chronic thrombotic material in major pulmonary arteries. In addition, about half of the patients suffer from a small vessel pulmonary arteriopathy that is a strong predictor of outcomes. Currently available treatment of CTEPH includes interventional strategies such as pulmonary endarterectomy (PEA) and balloon pulmonary angioplasty (BPA), and non-interventional strategies with PH-specific medications. A simple way of assessing small vessel disease is the degree of vasodilation (“vasoresponse”) in response to inhaled nitric oxide (iNO). In idiopathic pulmonary arterial hypertension vasoresponse serves as the best marker for good prognosis and treatment selection. In CTEPH, the prognostic value of vasoresponse remains unclear. Purpose We investigated the prognostic value of three definitions of vasoresponse to nitric oxide in patients with CTEPH. Methods We studied 325 CTEPH patients who underwent baseline diagnostic right heart catheterization (RHC) with 40ppm iNO testing at a general hospital (AKH) between 1995 and 2019. Cox regression models, adjusting for covariates including age, sex, comorbidities, and markers for disease severity at baseline, such as proBNP, GFR, NYHA functional class, were used to determine the risk of death or lung transplantation with respect to vasoresponse. We analysed three currently used definitions of vasoresponse to nitric oxide – the classical definition (CD) as a 10mmHg reduction in mPAP to a level below 40mmHg; an absolute definition (AD) as a 10mmHg reduction in mPAP regardless of resulting mPAP; and the percent definition (PD) as a 10% reduction in mPAP regardless of resulting mPAP. Results Patients had a median age of 62 (interquartile range [IQR]: 50, 71) at time of baseline right heart catheterization and 50% were female. During a median observation time of 5 years (IQR: 2.2, 9.0), the combined endpoint of death or lung transplantation occurred in 88 cases (27%). In the cox regression model PD vasoresponders, showed improved survival when undergoing PEA (p=0.0019). In PD vasoresponsive patients who were not given PEA surgery (n=66), PH medication therapy was associated with improved survival (p=0.0053), whereas BPA had no association with survival (p=0.58). In PD non-vasoresponsive patients who were not given PEA surgery (n=107) BPA improved survival (p&amp;lt;0.0001), whereas PH medication therapy did not improve survival (p=0.08). Conclusion The PD vasoresponse to iNO carries valuable prognostic information about freedom from death or lung transplantation in patients with CTEPH. In patients who are not eligible for PEA, PD vasoresponse can improve optimal therapy selection. Funding Acknowledgement Type of funding sources: None.

Chronic thromboembolic pulmonary hypertension and left ventricular filling pressures

Abstract Background Chronic thromboembolic pulmonary hypertension (CTEPH) is characterized by chronic obstruction of major pulmonary arteries with organized thrombi and is classified as pre-capillary pulmonary hypertension (PH) by the current hemodynamic definition of the guidelines. However, clinical risk factors for PH due to left heart disease including features of the metabolic syndrome, left-sided valvular heart disease and stable ischemic heart disease can be frequently observed in patients with CTEPH. The aim of this study was to investigate the prevalence, mechanisms and prognostic implications of elevated left ventricular filling pressures (LVFP) in patients with CTEPH. Methods 394 consecutive CTEPH patients undergoing a first diagnostic right and left heart catheterization were included in this study. mPAWP and LVEDP were utilized for assessment of LVFP. Two cutoffs were applied to identify patients with elevated LVFP: (1) mPAWP and/or LVEDP &amp;gt;15 mmHg as recommended by the current PH guidelines and (2) mPAWP and/or LVEDP &amp;gt;11 mmHg, which is the upper limit of normal in healthy subjects. Clinical and echocardiographic features as well as long-term mortality data were assessed. Results LVFP was &amp;gt;15 mmHg in 41 (10.4%) and &amp;gt;11 mmHg in 155 patients (39.3%). Univariable logistic regression analysis identified age, body mass index, systemic hypertension, diabetes, atrial fibrillation, mitral regurgitation and left atrial volume as significant clinical predictors of elevated LVFP. Systemic hypertension, atrial fibrillation, mitral regurgitation and left atrial volume remained independent determinants of LVFP in adjusted analysis. LVFP &amp;gt;11 mmHg was associated with worse long-term survival (p-logrank = 0.020). Conclusions Elevated LVFP is common in patients with CTEPH at the time of diagnosis. Elevated LVFP in CTEPH appears to be due to comorbid left heart disease. CTEPH patients with LVFP &amp;gt;11 mmHg have worse outcomes. Funding Acknowledgement Type of funding sources: None.

ADULT CONGENITAL HEART DISEASE HEALTH SERVICES IN CANADA-WHERE HAVE WE COME IN THE PAST 15 YEARS

ADULT CONGENITAL HEART DISEASE HEALTH SERVICES IN CANADA-WHERE HAVE WE COME IN THE PAST 15 YEARS

Improved Survival for Patients with Systemic Sclerosis-associated Pulmonary Arterial Hypertension: The Johns Hopkins Registry.

Rationale: To date, it remains unclear whether recent changes in the management of patients with systemic sclerosis-associated pulmonary hypertension (SSc-PH) have improved survival. Objectives: To describe a cohort of patients with SSc-PH and compare their characteristics and survival between the last two decades. Methods: Patients with SSc-PH prospectively enrolled in the Johns Hopkins Pulmonary Hypertension Center Registry were grouped into two cohorts based on the date of diagnostic right heart catheterization: cohort A included patients whose disease was diagnosed between 1999 and 2010, and cohort B included those whose disease was diagnosed between 2010 and 2021. Patients' characteristics were compared between the two cohorts. Measurements and Main Results: Of 504 patients with SSc-PH distributed almost equally between the two cohorts, 308 (61%) had World Symposium on Pulmonary Hypertension group 1, 43 (9%) had group 2, and 151 (30%) had group 3 disease. Patients with group 1 disease in cohort B had significantly better clinical and hemodynamic characteristics at diagnosis, were more likely to receive upfront combination pulmonary arterial hypertension therapy, and had a nearly 4-year increase in median transplant-free survival in univariable analysis than those in cohort A (P < 0.01). Improved transplant-free survival was still observed after adjusting for patients' baseline characteristics. In contrast, for group 2 or 3 patients with SSc-PH, there were no differences in baseline clinical, hemodynamic, or survival characteristics between the two cohorts. Conclusions: This is the largest single-center study that compares clinical characteristics of patients with SSc-PH between the last two decades. Transplant-free survival has improved significantly for those with group 1 disease over the last decade, possibly secondary to earlier detection and better therapeutic management. Conversely, those with group 2 or 3 disease continue to have dismal prognosis.