Obtuse Marginal Branch Research Articles

AN UNUSUAL RIGHT CORONARY ARTERY EMERGING FROM DISTAL CIRCUMFLEX ARTERY

Introduction: Coronary artery anomalies (CAAs) affect around 1% of the general population, ranging from 0.3%-5.6% in studies on patients undergoing coronary angiography and in approximately 1% of routine autopsies. One of the rarest coronary artery anomalies is the single coronary artery (SCA). The prevalence of SCA is approximately 0.024% to 0.066% in patients who undergo coronary angiography. The SCA are asymptomatic in general. In some cases, the disease may appear with life-threatening symptoms.Case Description: A 53-year-old male was admitted to the hospital due to chest pain. He underwent coronary angiography. The angiography showed a very short left main coronary artery diving into LAD and LCX arteries in several millimeters. He had a big which had the same diameter in the distal part as the proximal part. After giving a big obtuse marginal branch, a smaller obtuse marginal branch, and a posterolateral branch, the circumflex continued to the right side of the heart with a slightly smaller diameter than the preceding parts. It was found that the patient had an anatomically different RCA, which originates from the distal circumflex artery. According to Lipton et al., our case represents an L-I type.Conclusion:A single coronary artery is commonly associated with other congenital cardiac anomalies, such as bicuspid aortic valve, coronary arteriovenous fistula, and transposition of the great arteries.SCA is a rare coronary artery anomaly. A detailed anatomical description of this anomaly will help diagnose coronary artery abnormalities.

Assessment of surgical revascularization completeness with quantitative myocardial blood flow distribution derived from CCTA in severe coronary artery disease

Abstract Background Complete revascularization remained the "holy grail" in the treatment of patients with severe coronary artery disease (CAD). However, there is no universally accepted definition of complete revascularization after coronary bypass graft surgery (CABG). The current assessment methods are visual, categorical, and biased by the operator's intention. Moreover, no method to date provides an individualized quantification of residual ischemia burden. Purpose We aim to provide an individualized method to assess the completeness of surgical revascularization through quantitative myocardial blood flow distribution derived from coronary computed tomography angiography (CCTA) that could reflect the actual functional ischemia burden after CABG. Methods Patients with 3VD and/or left main CAD were enrolled in the first-in-human FAST TRACK CABG trial for surgical revascularization guided solely by CCTA and fractional flow reserve derived from CCTA (FFRCT). Following CABG, the study protocol mandated a 30-day follow-up CCTA, which provides graft patency and topographical adequacy of the bypass graft anastomoses. The pre- and post-CABG CCTA were analyzed. The FFRCT value and percent myocardial blood flow distribution (%MBF) were computed for all 16 SYNTAX score segments using the validated method of Keulards et al(1). On pre-CABG CCTA, the myocardium located distal to the site where the FFRCT value dropped below 0.80 on the vessel centerline was considered ischemic, and the %MBF of the subtended myocardium was summed into the total percent ischemic myocardium (Figure 1). Following CABG, the segment was considered adequately revascularized when a non-narrowed graft was anastomosed distally to the site of FFRCT≤0.8 on the pre-operative CCTA. The change in percent ischemic myocardium and the residual ischemic burden were calculated for each patient (Figure 2). Results CCTA, FFRCT, and %MBF were obtained pre- and post-CABG in 96 patients, and the percent ischemic myocardium was computed per patient. At baseline, the average percent ischemic myocardium was 72.0(19.1)%. Post-CABG, the residual percent ischemic myocardium was 13.6(15.1)%. Residual percent ischemic myocardium <10% was achieved in 44 patients (44.8%). The first diagonal branch(n=13), distal LCX(n=12), and the first obtuse marginal branch(n=10) were the most frequent segments not revascularized, which subtended an average MBF of 12.2(3.5)%, 16.7(8.4)%, and 11.3(7.3)%, respectively. The main reason for inadequate revascularization was surgical deferral, with graft occlusion accounting for only 13.6% of the residual ischemic segments. Conclusion Percent ischemic myocardium and the completeness of surgical revascularization can be assessed with CCTA-derived %MBF. This novel method allows clinicians to assess the individualized ischemia burden and the completeness of revascularization that could be incorporated into personalized CABG planning.Figure 1Figure 2

Comparative analysis of the efficiency of the use of various types of conduits during coronary artery bypass grafting

The OBJECTIVE was to compare efficiency of the use of various types of conduits during coronary artery bypass grafting (CABG).METHODS AND MATERIALS. The retrospective study included 282 patients, who underwent CABG, performed with different types of conduits. The average age of the patients was 63.2±8.5 years; the majority of 231 patients (81.9%) were male. Patients were separated in 3groups depending on the use of conduits: the first one included patients after bimammary coronary artery bypass grafting (n=77); the second one involved coronary artery bypass grafting using radial artery(n=87); the third one included patients with venous conduits (n=77). The main endpoint of the study was the development of conduit dysfunctions in the long-term period according to diagnostic coronary artery bypass grafting.RESULTS. The average follow-up time in the long-term period was 44.9±39 months. During this period, 198 patients underwent diagnostic coronary artery bypass grafting. According to the results of the analysis, the greatest effectiveness was observed in groups using arterial conduits – the left internal thoracic artery and radial artery. For example, the incidence of dysfunction of the left internal thoracic artery in the anterior artery basin was 8.2%; the incidence of dysfunction of radial artery in the right artery basin was 12.5 %, and in the obtuse marginal branch basin – 11.5 %; while the incidence of venous conduits’ dysfunction varied, reaching its maximum of 42.8 %.CONCLUSIONS. Thus, the greatest efficiency was observed when using the left and the right internal thoracic arteries, thereafter by the radial artery. The results of using venous conduits were lower.

MYOCARDITIS, CORONARY ARTERY DISSECTION OR BOTH: A JUVENILE ENIGMA

Abstract A 26–year–old man was admitted to the Coronary Care Unit for severe, non–irradiated, oppressive anterothoracic pain. He had no relevant pathological history, but reported an episode of gastroenteritis the week before. EKG showed sinus rhythm and accelerated idioventricular rhythm phases. Blood pressure and 2D echo were normal. Inflammation indeces were negative, hsTnT reached a peak of 2026 ng/L. Despite the absence of inflammation signs, our first guess was myocarditis. Cardiac magnetic resonance (CMR) was performed: T2w–STIR images showed edema of the middle inferior wall and of the mid–basal anterior and anterolateral wall, while T1–weighted post gadolinium images showed transmural enhancement of the mid–basal anterior, antero lateral and inferior walls with a dubious origin from the sub endocardium in the anterior and anterolateral segments; LVEF was 55%. Invasive coronary angiography (ICA) was performed to rule out ischemic etiology: LAD showed a very thin lumen in its periphery and two obtuse marginal branches had an amputated appearance: it made us think of healing dissections. Then it turned out that the patient have been working out with heavy weights the day before: we therefore considered spontaneous coronary artery dissection. Such hypothesis was consistent with the absence of inflammations indices, but didn’t explain the basal and middle inferior involvement that CMR had shown. On the other hand, the angiographic finding may be consistent with peripheral vascular suffering linked to myocarditis induced inflammation. To date, we haven’t found univocal interpretation. Anti–remodeling therapy with IACE and beta blockers was administered, in addition to acetylsalicylic acid. CMR will be performed in two months and may provide further results once the edema will be reabsorbed. ICA will be repeated to make sure that distal coronary blood flow is improved. Take Home Messages Myocarditis can also occur with no signs of inflammation. In myocarditis it has been demonstrated that slower distal coronary blood flow may occur, due to the increase in peripheral vascular resistance linked to the presence of edema. In the acute phase, especially if CMR is performed very early, the large amount of edema can make the enhancement transmural, masking the site of origin of the damage.

ACUTE CORONARY SYNDROME IN A PATIENT WITH LEFT SUBCLAVIAN OCCLUSION AND ANTEROLATERAL CORONARY STEAL

Abstract This is a 57–year–old male patient suffering from multiple cardiovascular risk factors: obesity, arterial hypertension, dyslipidemia, type 2 diabetes mellitus, active smoker. Chronic obstructive pulmonary disease. Stage 2 chronic kidney disease. Peripheral vascular disease with previous bilateral thromboendarterectomy and percutaneous revascularization of the lower limbs. Stable angina for which three years ago he underwent Coronary Artery Bypass Graft: left internal mammary artery (LIMA) to left anterior descending artery combined with saphenous vein grafts to the main obtuse marginal branch. The patient presented with Acute Coronary Syndrome non ST–segment elevation myocardial infarction (N–STEMI), intermittent episodes of chest pain due to mild exertion in the previous days. Antero–lateral ST depression and inverted T waves, associated with a mild reduction in left ventricular systolic function due to hypokinesia of the antero–lateral walls and increased troponin values were present. Coronary angiography documented patency of the LIMA graft without evidence of any culprit lesions on the coronary branches. However, selective angiography documented a sub–occlusion of the proximal left subclavian artery (Figure 1). A computed tomography scan confirmed a hyperdense calcified plaque occluding 95% of the origin of the left subclavian artery. The patient then underwent angioplasty with stenting of the left subclavian artery (Figure 2). Subclavian coronary steal syndrome usually presents with exertional angina, but rarely can cause Acute Coronary Syndrome. During coronary angiography performed for Acute Coronary Syndrome and in the absence of detection of clear coronary culprit lesions, selective angiography of the subclavian artery may confirm the suspicion of coronary steal syndrome.

Left anterior descending coronary T-wave inversion pattern (Wellens’ syndrome) associated with myopericarditis and a normal left coronary artery

Background: Wellens’ syndrome is characterised by a history of chest pain with an abnormal electrocardiogram (EKG), demonstrating biphasic or deeply inverted T waves in leads V2–3 (may extend to involve all precordial and lateral limb leads – the type B Wellens’ pattern). A Wellens’ EKG pattern is considered highly specific for critical stenosis involving the ostial/proximal left anterior descending artery (LAD). However, there are no reported cases of an association of a Wellens’ EKG pattern with myopericarditis. Here, we present such a rare case. Case description: A thirty-one-year-old female with known essential hypertension and psoriatic arthritis presented with a constant, central chest pain radiating to the shoulders and back. The patient’s physical examination was unremarkable at presentation other than elevated blood pressure at 170/68 mmHg. An EKG at presentation demonstrated deep symmetric T-wave inversions in anterolateral leads with elevated high-sensitivity troponin, and an elevated erythrocyte sedimentation rate. The patient was referred to the cardiac catheterisation laboratory for concerns of a Wellens’ EKG pattern; however, invasive angiography demonstrated only obtuse marginal branch disease – no LAD disease was noted. Cardiac magnetic resonance (CMR) imaging confirmed the diagnosis of myopericarditis and absence of myocardial infarction. The patient was medically managed and discharged home in a stable condition. Conclusion: In literature and established clinical practice, the Wellens’ EKG pattern is considered highly concerning for critical ostial/proximal LAD stenosis. However, we now propose that myopericarditis may be considered in a differential diagnosis for this EKG pattern.

Should the left internal mammary artery (LIMA) be imaged before radiotherapy in cases of unexpected early acute coronary syndrome?

Abstract Funding Acknowledgements None. Case A 41-year-old male patient presented to the cardiology outpatient clinic with a complaint of exertional chest pain persisting for the past 4 months, along with occasional palpitation attacks. In his medical history, aside from being diagnosed with lymphoma 15 years ago, there were no known additional comorbidities. The electrocardiogram (EKG) revealed sinus rhythm (84 beats/minute), and the blood tests showed creatinine: 0.81 mg/dL, WBC: 11.26 mm^3, LYM: 3.69 mm^3. Transthoracic echocardiography demonstrated an ejection fraction (EF) of 60%, with no additional pathologies except for grade 1 diastolic dysfunction. Considering the presence of typical chest pain, coronary imaging was performed to assess for stable angina. The coronary imaging revealed a lesion extending from the left main coronary artery (LMCA) to the proximal left circumflex artery (CX), with an 80% stenosis in the mid-segment of the LMCA, a 60% stenosis at the narrowest point of the CX proximal segment, and an 80% stenosis in the proximal right coronary artery (RCA). The left circumflex artery obtuse marginal branches (CX OM) appeared thin and extensively diseased (Figure-1) The patient was promptly scheduled for early coronary artery bypass grafting (CABG), transferred to the cardiac surgery intensive care unit, and underwent a successful coronary bypass procedure with LAD-LIMA, Ao-saphenous-IM-saphenous-CxOM1 (sequential) grafting. Throughout the postoperative follow-up period, the patient continued to experience exertional chest pain despite medical treatment. A repeat coronary angiography was performed, revealing that the bypass grafts were opened, but a diffuse 80% stenosis was detected at the mid-segment of the LIMA graft, prior to the anastomosis.(Figure-2) Successful stent placement was performed at the narrowest point of the LIMA mid-segment (Figure-3).The patient had no anginal complaints during post-procedure follow-up and has been stable under observation. Discussion Routine clinical practice does not involve LIMA imaging in patients who have undergone diagnostic coronary angiography with multi-vessel involvement and a CABG decision. However, the use of coronary artery bypass graft surgery (CABG) may entail a risk of rendering the graft unusable due to extensive mediastinal fibrosis and radiation-induced damage to the left or right mammary artery. Therefore, in patients with a history of radiation exposure in the thoracic region and a CABG decision, the visualization of the intermammary artery during coronary angiography and the consideration of alternative grafts, such as the radiation-free radial artery, or the necessity for high-risk percutaneous stent implantation, should be discussed.figure-1figure-2

Comparison of clinical effects of coronary artery bypass grafting between left anterior small thoracotomy approach and lower-end sternal splitting approach.

To compare the clinical effects of coronary artery bypass grafting (CABG) between the left anterior small thoracotomy (LAST) and lower-end sternal splitting (LESS) approaches for coronary artery disease. In total, 110 patients who underwent LAST from October 2015 to December 2020 in Tianjin Chest Hospital were selected as the observation group. Patients who underwent the LESS approach during the same period were analyzed. The propensity score was calculated by a logistic regression model, and nearest-neighbor matching was used for 1:1 matching. The length of hospital stay and ventilator support time were significantly shorter in the LAST than LESS group. The target vessels in the obtuse marginal branch and posterior left ventricular artery branch grafts were significantly more numerous in the LAST than LESS group, but those in the right coronary artery graft were significantly less numerous in the LAST group. CABG using either the LAST or LESS approach is safe and effective, especially in low-risk patients. The LAST approach can achieve complete revascularization for multivessel lesions and has the advantages of less trauma and an aesthetic outcome. However, it requires a certain learning curve to master the surgical techniques and has specific surgical indications.

Abstract 12780: Impact of Target Vessel on the Procedural Techniques and Outcomes of Chronic Total Occlusion Percutaneous Coronary Intervention

Introduction: There is limited information on the impact of the target vessel on the procedural techniques and outcomes of chronic total occlusion (CTO) percutaneous coronary intervention (PCI). Methods: We analyzed the baseline clinical and angiographic characteristics and procedural outcomes of 11,580 CTO PCIs performed between 2012 and 2022 at 44 centers. Results: The most common CTO target vessel was the right coronary artery (RCA) (53.1%) followed by the left anterior descending artery (LAD) (26.0%) and the left circumflex artery (LCX) (19.8%). RCA CTO lesions were longer and more complex with higher J-CTO score compared with LAD or LCX CTO lesions. Technical success was higher among LAD (88.8%) lesions when compared with RCA (85.7%) or LCX (85.8%) lesions (p<0.001). The incidence of major adverse cardiovascular events (MACE) was overall 1.9% (n=220) and was similar among target vessels (p=0.916). There was a tendency towards more frequent utilization of the retrograde approach for more proximal occlusions in all three target vessels. When compared with all other RCA lesions combined, distal RCA lesions had higher technical success (87.7% vs. 85.3%; p=0.048). Technical success was similar between various locations of LAD CTOs (p=0.704). First/second/third obtuse marginal branch had lower technical success when compared with all other LCX lesion locations (82.7% vs. 86.8%; p=0.014). There was no association between MACE and CTO location in all three target vessels. Conclusions: LAD CTO PCIs had higher technical and procedural success rates among target vessels. The incidence of MACE was similar among target vessels, and also among various locations within the target vessel.

Anterolateral Papillary Muscle Rupture Predicted by Post-Infarction Inflammatory Markers.

BACKGROUND The incidence of papillary muscle rupture (PMR), a mechanical complication of acute myocardial infarction, has decreased in the reperfusion era; however, its fatality rate remains high. Timely recognition and prompt initiation of treatment for PMR are important to avoid prolonged cardiogenic shock; however, the symptoms of PMR are nonspecific, and early diagnosis is often difficult. CASE REPORT A 72-year-old woman with nausea for 2 days presented with ST-segment elevation myocardial infarction with obstruction of the obtuse marginal branch and 75% stenosis of the first diagonal branch. Percutaneous coronary intervention was performed to revascularize the obtuse marginal lesion, which was over thrombolysis in myocardial infarction grade 2 flow. After percutaneous coronary intervention, the patient developed fever, an elevated C-reactive protein level, and an increased neutrophil-to-lymphocyte ratio (NLR). The patient showed no signs of infection but elevated inflammatory marker levels, with C-reactive protein rising to 39.32 mg/dL and NLR to 15. On postoperative day 4, the patient's clinical condition rapidly deteriorated, resulting in circulatory failure. Transthoracic echocardiography showed anterolateral PMR, and urgent surgical mitral valve replacement was performed. On day 32, the patient was discharged from the hospital, and at the 1-year follow-up, she remained in good health. CONCLUSIONS When there are multiple lesions, including the obtuse marginal and diagonal branches, anterolateral PMR should be suspected as the cause of cardiogenic shock. Performing point-of-care echocardiography and closely monitoring C-reactive protein levels and NLR can be helpful to detect PMR early.

P245 IMPLICATIONS IN PHARMACOLOGICAL AND ELECTRICAL OPTIMIZATION IN HEART FAILURE: A EMBLEMATIC CASE

Abstract We describe the case of an 82–year–old man with permanent atrial fibrillation in oral anticoagulation therapy. Former smoker. Diabetes mellitus. In 2009, subacute MI with PTCA/DES of anterior descending artery and obtuse marginal branch, critical stenosis of circumflex artery, right coronary artery occluded. Infrarenal aorta occlusion. Echocardiography TT mild–moderate mitral regurgitation. Ejection fraction (EF) preserved. Inferior wall akinesia. In 2019 hospitalization for heart failure due to severe bradyarrhythmia in atrial fibrillation. In therapy with bisoprolol 10 mg/day Echocardiography FE 35%, moderate–severe functional mitral regurgitation, PAPs 55 mmHg. Arterial pressure 100/85 Sat 2O 90% Treatment at discharge: furosemide 75 mg/day, bisoprolol 7,5 mg/day, Metformina 500 mg/day, potassium canrenoate 50 mg/day atorvastatin 40 mgday and warfarin,Ramipril 2.5 mg/day, allopurinol 150 mg/day. In 2020 new hospitalization for heart failure. NYHA III–IV; BNP 1890 pg/ml. Beta–blocker therapy reduced to bisoprolol 3.75 day for pulmonary hypertension and bradycardia, furosemide increased to 100 mg/day, possibly further titratable on the basis of renal function, blood electrolytes and clinical response, maintaining restriction of daily liquids at about 1000 cc. Initiated Sacubitril/Valsartan 24/26 mgx 2 /day. Coronary angiography was not possible due to occlusion of the abdominal aorta and right radial artery (1,2,3). CT CORO performed with relief of the interventricular branch occluded in the middle section; patent obtuse marginal branch stent; right coronary artery occluded. Abdominal aorta occluded at the level of the renal arteries. The patient was submitted to CRT–D implant for bradycardia and wide QRS like left bundle branch block. Glyphozine associated with Metformin. Echocardiography TT LVEF 40%, moderate functional MR, PAPS 35 mmHg. NYHA II. Edema resolution No hospitalizations for decompensation. titrated ARNI at 49/51 mg x 2/day, and the beta blocker Cardicor 5mg/day. At remote monitoring decreased ventricular catheter impedance. What does the case tell us? The combination of Sacubitril/Valsartan and Glifozine determined an inverse remodeling of the heart. The combination of Sacubitril/Valsartan and Glifozine improved cardiac compensation and clinically stabilized the patient.

C1 COMPLETE HEART BLOCK AS A RARE MANIFESTATION OF GRANULOMATOSIS WITH POLYANGITIS: A CASE REPORT

Abstract A 42–year–old male with prior smoking habit presented at our emergency department after atraumatic syncope preceded by severe pain in the left lower limb. One month prior to presentation, due to persistence of nonproductive cough he underwent a chest computed tomography (CT), which showed 2 pulmonary nodules with hypercaptation at PET performed later (figure 1). The 12–lead electrocardiogram showed sinus rhythm with complete atrioventricular block and ventricular escape rhythm at 40 bpm (figura 1). Ecofast revealed a mildly impaired left ventricular systolic function (left ventricular ejection fraction [LVEF] 45%) with basal septal hypokinesis. Laboratory assessment showed leukocytosis (marked neutrophilia and eosinophilia), thrombocytosis anemia, elevated C–reactive protein (193 mg/dl), troponin I (18483 ng/L), NTproBNP (14627 ng/l) and creatinine (2.27 mg/dL) levels. The patient was transported to the catheterization laboratory for temporary pacemaker insertion and coronary angiography, which depicted distal occlusion of the first septal branch (Figure 2A), the first diagonal branch (Figure 2B) and the obtuse marginal branch (Figure 2C). After the procedure due to persistent ischemia of the left lower limb, several unsuccessful procedures to restore limb vascularization by means of locoregional thrombolysis and percutaneous angioplasty were attempted, but a leg amputation above the knee was eventually performed after few days. Neoplastic markers, blood cultures and urine cultures resulted negative, urine sediment examination showed cylinders, leucocytes and microhematuria. A brain/facial bones CT scan was performed, showing left maxillary sinusitis (figure 1). A rheumatologic screening was also performed, showing high titer of cANCA(125 UI/ml) hinting at a systemic vasculitis. The histopathological results of the amputated limb depicted marked necrotizing vasculitis with extensive involvement of small–medium caliber and larger caliber arterial vessels (figure 2). Based on these clinical and laboratory findings, a diagnosis of granulomatosis with polyangiitis (GPA) was made. The patients was treated with ev methylprednisolone and rituximab. After the induction therapy, chest CT scan showed a marked reduction of the size of the pulmonary nodule (Figure 3); renal function progressively improved and physiological atrioventricular conduction being restored

P155 CT EVIDENCE OF PARTIAL ISCHEMIC PAPILLARY MUSCLE RUPTURE

Abstract A 77–year–old man was referred for coronary CT following an episode of prolonged chest pain that occurred about 30 days earlier, with subsequent onset of dyspnea on moderate exertion. Coronary CT demonstrated right dominance, occlusion of the right coronary artery, as well as severe stenosis of the distal segment of the left anterior descending artery and of the first obtuse marginal branch. CT scan also showed an intraventricular image consistent with partial rupture of the posteromedial papillary muscle (Figure 1). The patient was transferred to the emergency department. An ECG showed signs of inferolateral necrosis. Transthoracic echocardiography confirmed akinesia of the inferior and inferolateral walls and of the basal segment of the inferior septum, with severe mitral valve insufficiency from anterior leaflet prolapse (A3 scallop) from partial rupture of the posteromedial papillary muscle (Figure 2). Transesophageal echocardiography confirmed the diagnosis (Figure 3). The patient was admitted to the CCU and underwent coronarography, which confirmed the severe triple vessel coronary artery disease with occlusion of the right coronary artery, and then urgent mitral valve replacement with bioprosthesis and aortocoronary bypass with saphenous vein grafting to the posterior descending artery. The postoperative course was uneventful. Ischemic papillary muscle rupture is a rare cause of mitral insufficiency. Papillary rupture typically occurs within 5 days of an acute myocardial infarction, and causes mitral insufficiency by prolapse and flail of one or, more rarely, both mitral valve leaflets. The posteromedial papillary muscle is most commonly affected, since the anterolateral papillary muscle has dual supply from the anterior interventricular artery and the circumflex artery. Papillary muscle rupture can be total or partial; however, most cases of partial rupture progress to complete rupture and therefore require urgent surgical treatment. The peculiarity of this case lies in the fact that it is the first case described in the literature of a papillary muscle rupture documented on CT.

Revisit of the CatLet (Hexu) angiographic scoring system: a narrative review.

We have recently developed the Coronary Artery Tree description and Lesion EvaluaTion (CatLet or Hexu, invented by He and Xu) angiographic scoring system, which, considering the coronary anatomy in its diversity, the stenosis degree of a coronary artery, and the myocardial territory subtended by the diseased coronary artery, can be utilized to predict clinical outcomes for patients with acute myocardial infarction (available at www.catletscore.com). Its values for clinical practice and coronary artery disease research are building upon. Over the past two years, the principles underlying this novel angiographic scoring system do not materially change although slight adjustments have really happened. Given these adjustments and the scoring experience gained in daily use, we think that it is necessary to elaborate on these points so that readers with interest are capable to better use this CatLet or Hexu angiographic scoring system both in clinical practice and in scientific research. The principles underlying this novel angiographic scoring system include the 17-myocardial segmental model, law of competitive blood supply, and law of flow conservation. The adjustments made to this novel angiographic scoring system include: (I) the short axis of the left ventricle at the basal level is used to characterize the six types of right coronary artery size; (II) segments marked with 'X and 'S have a unified preset difference of one segment as adopted in the characterization of left anterior descending artery; (III) segments marked with '+ have been added to explain the rare variability in the obtuse marginal branches or in the posterolateral vessels in some cases. The CatLet or Hexu angiographic scoring system strictly follows the law of flow conservation in weighting assignment, and the lesion scoring correction has been additionally emphasized and detailed. The elaboration on these adjustments and scoring experience gained on the CatLet or Hexu angiographic scoring system will help to boost its use in cardiovascular field. The utilities of this novel angiographic scoring system have been preliminarily validated and its future is deserving of being anticipated.

Myocardial Infarction in a Young Female Patient with Subtotal Occlusion of the Mid OM Branch: A Case Report and Review of Potential Causes

Chest pain is a common presenting symptom in emergency departments, and its evaluation and management require careful consideration of various potential causes, ranging from benign musculoskeletal pain to serious cardiac conditions. Myocardial infarction (MI) is a well-known cause of chest pain, particularly in older individuals with risk factors such as hypertension, hyperlipidemia, and smoking history. However, MI in young patients without significant risk factors is relatively uncommon and can pose diagnostic challenges. In this case report, we describe the case of a 26-year-old female with no pertinent past medical history who presented to ED with acute chest pain and was diagnosed with a subtotal occlusion of the mid obtuse marginal (OM) branch of the coronary artery requiring two drug eluting stents to be placed.

Relationship between epicardial adipose tissue attenuation and coronary artery disease in type 2 diabetes mellitus patients.

High epicardial adipose tissue (EAT) attenuation is a key characteristic of adipose tissue dysfunction and associated with coronary artery disease (CAD). As little is known about the modulation of EAT attenuation by metabolic disorders, we investigated the association between EAT attenuation and CAD risk factors, CAD presence and CAD severity in type 2 diabetes mellitus (T2DM) patients. We included 276 inpatients with T2DM and 305 control patients with normal glucose metabolism (NGM), who underwent cardiac computed tomography angiography (CCTA) and coronary artery calcium (CAC) scoring. EAT attenuation and volume were evaluated by contrast-enhanced CCTA image analysis. Furthermore, segment stenosis scores (SSSs) of the left main coronary artery (LMCA), left anterior descending artery (LAD), left circumflex artery (LCX), right coronary artery (RCA), diagonal/intermediate branch (D/I) and obtuse marginal branch (OM) were calculated to assess CAD severity. T2DM patients showed higher significant CAC scores, coronary plaque prevalence, total SSSs and LMCA-SSSs, LAD-SSSs, LCX-SSSs, RCA-SSSs and D/I-SSSs compared with NGM controls. In contrast to NGM controls, EAT volume was significantly increased in T2DM patients, whereas EAT attenuation was similar. In T2DM patients, EAT attenuation was associated with discrete CAD risk factors, the presence of coronary and triple-vessel plaques, as well as LAD-SSSs, LCX-SSSs, RCA-SSSs and total SSSs. In addition, EAT attenuation was only associated with the total SSS of calcified plaques, but not with noncalcified plaques. In T2DM patients, high EAT attenuation is associated with the presence and severity of CAD in general and with coronary stenosis caused by calcified plaques in particular.

Impact of target vessel on the procedural techniques and outcomes of chronic total occlusion percutaneous coronary intervention.

There is limited information on the impact of the target vessel on the procedural techniques and outcomes of chronic total occlusion (CTO) percutaneous coronary intervention (PCI). We analyzed the baseline clinical and angiographic characteristics and procedural outcomes of 11,580 CTO PCIs performed between 2012 and 2022 at 44 centers. The most common CTO target vessel was the right coronary artery (RCA) (53.1%) followed by the left anterior descending artery (LAD) (26.0%) and the left circumflex artery (LCX) (19.8%). RCA CTOs were longer and more complex, with a higher Japanese CTO score compared with LAD or LCX CTOs. Technical success was higher among LAD (88.8%) lesions when compared with RCA (85.7%) or LCX (85.8%) lesions (P less than .001). The incidence of major adverse cardiovascular events (MACE) was overall 1.9% (n = 220) and was similar among target vessels (P=.916). There was a tendency toward more frequent utilization of the retrograde approach for more proximal occlusions in all 3 target vessels. When compared with all other RCA lesions combined, distal RCA lesions had higher technical success (87.7% vs 85.3%; P=.048). Technical success was similar between various locations of LAD CTOs (P=.704). First/second/third obtuse marginal branch had lower technical success when compared with all other LCX lesion locations (82.7% vs 86.8%; P=.014). There was no association between MACE and CTO location in all 3 target vessels. LAD CTO PCIs had higher technical and procedural success rates among target vessels. The incidence of MACE was similar among target vessels and among various locations within the target vessel.

Novel Approach for Assessing Postinfarct Myocardial Injury and Inflammation Using Hybrid Somatostatin Receptor Positron Emission Tomography/Magnetic Resonance Imaging.

Novel Approach for Assessing Postinfarct Myocardial Injury and Inflammation Using Hybrid Somatostatin Receptor Positron Emission Tomography/Magnetic Resonance Imaging.

362 COMPLETE HEART BLOCK AS A RARE MANIFESTATION OF GRANULOMATOSIS WITH POLYANGIITIS: A CASE REPORT

Abstract A 42-year-old male with prior smoking habit presented at our emergency department after atraumatic syncope preceded by severe pain in the left lower limb. He had no past relevant medical history until one month prior to presentation, when the onset and persistence of nonproductive cough deemed the performance of a chest computed tomography (CT), which showed a 28 mm pulmonary nodule. A positron emission tomography-CT scan performed thereafter showed hypercaptation of the apical pulmonary nodule (SUV 6.87), and hypercaptation of the left nasal cavities. He was not on daily medications. On presentation the patient complained of dyspnoea at rest with no chest pain. On physical examination the left foot was cold and numb with no pedidial pulses. Laboratory assessment showed leukocytosis, thrombocytosis, anemia and elevated C-reactive protein, troponin I, NTproBNP and creatinine levels. The 12-lead electrocardiogram showed sinus rhythm with complete atrioventricular block and ventricular escape rhythm at 40 bpm; the transthoracic echocardiography revealed a mildly impaired left ventricular systolic function with basal septal hypokinesis; a chest-CT scan confirmed the stability of the aforementioned pulmonary lesions. The patient was transported to the catheterization laboratory for temporary pacemaker insertion and coronary angiography, which depicted distal occlusion of the first septal branch, the first diagonal branch and the obtuse marginal branch; no percutaneous coronary intervention was performed. The patient was then transferred to our Coronary Intensive Care Unit: due to persistent ischemia of the left lower limb, and several unsuccessful procedures to restore limb vascularization, a leg amputation above the knee was performed on day 2 of hospitalization. Meanwhile, the patient also developed fever, epididymitis, digital infarcts with bilateral hand purpura, upper and lower extremities paresthesia, worsening renal failure, persistent anemia and leukocytosis with eosinophilia. Neoplastic markers, blood cultures and urine cultures resulted negative; urine sediment examination showed cylinders, leucocytes and severe dysmorphic microhematuria suggestive of glomerulonephritis; bronchoalveolar lavage showed inflammatory cells. A rheumatologic screening was also performed, showing high titer of cANCA (125 UI/ml) hinting at a systemic vasculitis. The histopathological results of the amputated limb depicting marked necrotizing vasculitis with extensive involvement of small-medium caliber and larger caliber arterial vessels. Based on these clinical and laboratory findings, a diagnosis of granulomatosis with polyangiitis (GPA) with myocardial infarction due to coronary involvement and subsequent atrioventricular block was made on day 4 of hospitalization. Daily 500 mg boluses of intravenous methylprednisolone were administered for three days since day 4 of hospitalization, followed by high dose oral glucocorticoids (prednisone 1 mg/kg/day) and subsequent remission induction therapy with rituximab 375 mg/m2 weekly. Renal function progressively improved; heart conduction abnormalities gradually recovered and there was a marked reduction of the size of the pulmonary nodule. GPA presents remains one of the most challenging diagnostic dilemmas in clinical medicine. Despite we performed a prompt diagnosis, a leg amputation had to be done due to the common rapid progression of the disease. Clinicians should be aware of the various manifestations of GPA and bear in mind the possibility of coronary vasculitis.

806 BRIDGING COLLATERALS OF CHRONICALLY OCCLUDED LEFT INTERNAL MAMMARY ARTERY BYPASS GRAFT TO LEFT ANTERIOR DESCENDING ARTERY

Abstract Methods and results The internal mammary artery (IMA) is the conduit of choice to bypass the left anterior descending (LAD) coronary artery in patients eligible for coronary artery bypass grafting (CABG). In case of graft occlusion, it is still not clear whether it is better to revascularize the graft or the recipient native vessel, on top of optimal medical therapy. A 55-year-old man, with prior CABG, underwent urgent coronary angiography for an acute coronary syndrome. LAD CTO, severe proximal circumflex artery stenosis, and mild atherosclerosis of the right coronary artery were found. Moreover, a proximal occlusion of the venous graft to the obtuse marginal branch and LIMA CTO within the body of the graft were shown as well. Surprisingly, many well-developed bridging collaterals, arising close to the proximal cap of the LIMA occlusion, supplied the bloodstream circulation distal to the occlusion within the LIMA. At that time, a left main–proximal circumflex artery stenting was performed (3.5×24-mm Xience Sierra, Abbott) because that was judged the culprit lesion. One month later the patient still complained of effort angina and dyspnoea despite optimized antianginal medical therapy. The patient was scheduled for elective antegrade LIMA CTO PCI, considered the most appropriate treatment strategy. Indeed, the presence of a prior stent implanted in the left main– circumflex artery would have made difficult a proximal cap negotiation and its penetration by guidewires in case of antegrade LAD CTO PCI. Thus, the LIMA CTO negotiation was initially attempted with a Fielder FC guidewire (Asahi Intecc) and a supporting Corsair Pro (Asahi Intecc) microcatheter. The polymeric soft wire prolapsed preferentially into the bridging collaterals without the chance to engage the CTO proximal cap. Finally, a moderate-weight hydrophilic GAIA second (Asahi Intecc) succeeded in cap penetration and final CTO crossing. After lesion predilatation with a 2.0×15-mm balloon (Emerge, Boston Scientific), 2 overlapped stents, respectively 2.75×44 mm and 3.0×18 mm (VIVO ISAR, Translumina) were deployed and postdilated by a 3.0×15-mm non-compliant balloon (Accuforce, Terumo). The final result was deemed very satisfactory with a TIMI 3 flow. Conclusions Many studies showed that IMA has active biological functions, providing a sort of protection against atherosclerosis and self-reparative properties. These biological properties might justify the IMA high long-term patency rates as CABG conduits. The development of bridging collaterals in this patient, represents a clear proof of the LIMA self-reparative properties. Whereas bridging collaterals are a common feature of coronary CTO, their development in a LIMA bypass graft represents a unique finding which requires further investigation.